Molecular characterization of 'Candidatus Borrelia tachyglossi' (family Spirochaetaceae) in echidna ticks, Bothriocroton concolor.
Recently, a novel species of the genus Borreliawas identified in Bothriocroton concolor and Ixodes holocyclus ticks from echidnas. Analyses of 16S rRNA and flaB genes identified three closely related genotypes of this bacterium (Borrelia sp. Aus A-C) that were unique and distinct from previously described borreliae. Phylogenetic analyses of flaB (763 bp), groEL (1537 bp), gyrB (1702 bp) and glpQ (874 bp) gene sequences and concatenated sequences (3585 bp) of three gene loci (16S rRNA, flaB and gyrB) were consistent with previous findings and confirm that this novel species of the genus Borrelia is more closely related to, yet distinct from, the Reptile-associated (REP) and Relapsing Fever (RF) groups. At the flaB locus, genotypes A, B and C shared the highest percentage sequence similarities (87.9, 88 and 87.9 %, respectively) with B.orrelia turcica (REP), whereas at the groEL and gyrB loci, these genotypes were most similar (88.2-89.4 %) to B.orrelia hermsii (RF). At the glpQ locus, genotypes A and B were most similar (85.7 and 85.4 % respectively) to Borrelia sp. Tortoise14H1 (REP). The presence of the glpQ gene, which is absent in the Lyme Borreliosis group spirochaetes, further emphasises that the novel species of the genus Borrelia characterized in the present study does not belong to this group. Phylogenetic analyses at multiple loci produced consistent topographies revealing the monophyletic grouping of this bacterium, therefore providing strong support for its species status. We propose the name 'CandidatusBorrelia tachyglossi', and hypothesize that this species of the genus Borrelia may be endemic to Australia. The pathogenic potential of this bacterium is not yet known.


Flexibility and bioactivity of insulin: an NMR investigation of the solution structure and folding of an unusually flexible human insulin mutant with increased biological activity.
The structure and folding of a novel human insulin mutant, [Thr(B27) --> Pro, Pro(B28) --> Thr]insulin (PT insulin), in aqueous solution and in mixtures of water and 2,2,2-trifluoroethanol (TFE) have been studied by NMR spectroscopy. It was found that PT insulin has a highly flexible structure in pure water and is present in at least two different conformations, although with an overall tertiary structure similar to that of native insulin. Furthermore, the native helical structures are poorly defined. Surprisingly, the mutant has a biological activity about 50% higher than native insulin. In contrast, in TFE/water solution the mutant reveals a propensity of forming a well-defined structure at the secondary structure level, similar to monomeric native insulin. Thus, as shown by a detailed determination of the structure from 208 distance restraints and 52 torsion angle restraints by distance geometry, simulated annealing, and restrained energy minimization, the native insulin helices (A2-A7, A13-A19, and B10-B19) as well as the beta-turn (B20-B23) are formed in 35% TFE. However, the amount of tertiary structure is decreased significantly in TFE/water solution. The obtained results suggest that only an overall tertiary fold, as observed for PT insulin in pure water, is necessary for expressing the biological activity of insulin, as long as the molecule is flexible and retains the propensity to form the secondary structure required for its receptor binding. In contrast, a compact secondary structure, as found for native insulin in solution, is unnecessary for the biological activity. A model for the receptor binding of insulin is suggested that relates the increased bioactivity to the enhanced flexibility of the mutant.


PD-L1 has distinct functions in hematopoietic and nonhematopoietic cells in regulating T cell responses during chronic infection in mice.
The inhibitory receptor programmed death 1 (PD-1) is upregulated on antigen-specific CD8+ T cells during persistent viral infections. Interaction with PD-1 ligand 1 (PD-L1) contributes to functional exhaustion of responding T cells and may limit immunopathology during infection. PD-L1 is expressed on both hematopoietic and nonhematopoietic cells in tissues. However, the exact roles of PD-L1 on hematopoietic versus nonhematopoietic cells in modulating immune responses are unclear. Here we used bone marrow chimeric mice to examine the effects of PD-L1 deficiency in hematopoietic or nonhematopoietic cells during lymphocytic choriomeningitis virus clone 13 (LCMV CL-13) infection. We found that PD-L1 expression on hematopoietic cells inhibited CD8+ T cell numbers and function after LCMV CL-13 infection. In contrast, PD-L1 expression on nonhematopoietic cells limited viral clearance and immunopathology in infected tissues. Together, these data demonstrate that there are distinct roles for PD-L1 on hematopoietic and nonhematopoietic cells in regulating CD8+ T cell responses and viral clearance during chronic viral infection.


Inhibitory interactions promote frequent bistability among competing bacteria.
It is largely unknown how the process of microbial community assembly is affected by the order of species arrival, initial species abundances and interactions between species. A minimal way of capturing competitive abilities in a frequency-dependent manner is with an invasibility network specifying whether a species at low abundance can increase in frequency in an environment dominated by another species. Here, using a panel of prolific small-molecule producers and a habitat with feast-and-famine cycles, we show that the most abundant strain can often exclude other strains--resulting in bistability between pairs of strains. Instead of a single winner, the empirically determined invasibility network is ruled by multiple strains that cannot invade each other, and does not contain loops of cyclic dominance. Antibiotic inhibition contributes to bistability by helping producers resist invasions while at high abundance and by reducing producers' ability to invade when at low abundance.


Retention of different-sized particles and derived gut fill estimate in tammar wallabies (Macropus eugenii): physiological and methodological considerations.
The capacity of the digestive tract is an important parameter in understanding digestive adaptations, particularly in herbivores. Measures of this capacity ('gut fill') are commonly performed in killed animals, which has ethical and logistical implications. Alternatively, dry matter gut contents (DMC) can be estimated in live animals from food intake, digesta retention and digestibility, based on physical principles (Holleman and White, Can. J. Zool. 67, 488-494, 1989). Although this method has been used to some extent, it still awaits thorough validation. Here we estimated DMC in seven tammar wallabies during 5-day feeding trials and compared the results to those gained from dissections immediately after the trials. Calculated DMC exceeded that actually measured by 29 ± 22%. A closer inspection of the data suggested that this was partly due to the fact that DMC as measured by dissection is susceptible to short-term influences such as daily variation in food intake, whereas the calculated DMC represents an integrative measure over the whole period of the feeding trial. Correlations between both the measured digesta retention times, and the calculated DMC, with the measured wet contents mass suggest that it is particularly the DMC determined via dissection that needs to be measured with care. For a comparison of gut capacities, the calculated DMC therefore can be considered adequate, but should for a more widespread use be validated in further studies including more species and experimental regimes controlling food intake variation. Additionally, we tested whether very small (100-500 μm) and small (500-1000 μm) particles were retained differently in the tammar wallabies. There was no indication of such a difference. Whether the macropod forestomach selectively passes a certain particle fraction (that represents microbes) with the generally faster-passing fluids remains to be investigated with even smaller markers, e.g. labelled bacteria.


Diabetes-associated breast cancer is molecularly distinct and shows a DNA damage repair deficiency.
Diabetes commonly affects patients with cancer. We investigated the influence of diabetes on breast cancer biology using a 3-pronged approach that included analysis of orthotopic human tumor xenografts, patient tumors, and breast cancer cells exposed to diabetes/hyperglycemia-like conditions. We aimed to identify shared phenotypes and molecular signatures by investigating the metabolome, transcriptome, and tumor mutational burden. Diabetes and hyperglycemia did not enhance cell proliferation but induced mesenchymal and stem cell-like phenotypes linked to increased mobility and odds of metastasis. They also promoted oxyradical formation and both a transcriptome and mutational signatures of DNA repair deficiency. Moreover, food- and microbiome-derived metabolites tended to accumulate in breast tumors in the presence of diabetes, potentially affecting tumor biology. Breast cancer cells cultured under hyperglycemia-like conditions acquired increased DNA damage and sensitivity to DNA repair inhibitors. Based on these observations, we conclude that diabetes-associated breast tumors may show an increased drug response to DNA damage repair inhibitors.


Synthesis of new 1,2,4-triazole-(thio)semicarbazide hybrid molecules: Their tyrosinase inhibitor activities and molecular docking analysis.
Tyrosinase inhibition is very important in controlling melanin synthesis. If melanin synthesis is not controlled in metabolism, an unwanted increase in melanin synthesis occurs. As melanin plays a role in the formation of skin color, its unusual levels cause some skin disorders such as pregnancy scars, age spots, and especially skin cancer (melanoma). However, the tyrosinase activity is also related to Parkinson's disease and some neurodegenerative diseases. For all these reasons, the medicinal as well as the cosmetic industries focus on research on tyrosinase inhibitors for the treatment of skin disorders and some neurodegenerative diseases. In this study, 32 new 1,2,4-triazole-(thio)semicarbazide hybrid molecules (6a-p and 7a-p) were synthesized, starting from 4-amino-1-pentyl-3-phenyl-1H-1,2,4-triazole-5(4H)-one. These compounds were evaluated for their inhibitory activity against mushroom tyrosinase. The results indicated that 6h, 6m, 6n, and 6p exhibited the most effective inhibitory activity, with IC50 values of 0.00162 ± 0.0109, 0.00166 ± 0.0217, 0.00165 ± 0.019, and 0.00197 ± 0.0063 μM, respectively, compared with kojic acid as the reference drug (IC50 = 14.09 ± 0.02 μM). Also, molecular docking analyses were performed to suggest possible binding poses for the ligands. As a result, derivatives 6h, 6m, 6n, and 6p can be used as promising tyrosinase inhibitor candidates in the medicinal, cosmetics, or food industries.


Toward brain correlates of natural behavior: fMRI during violent video games.
Modern video games represent highly advanced virtual reality simulations and often contain virtual violence. In a significant amount of young males, playing video games is a quotidian activity, making it an almost natural behavior. Recordings of brain activation with functional magnetic resonance imaging (fMRI) during gameplay may reflect neuronal correlates of real-life behavior. We recorded 13 experienced gamers (18-26 years; average 14 hrs/week playing) while playing a violent first-person shooter game (a violent computer game played in self-perspective) by means of distortion and dephasing reduced fMRI (3 T; single-shot triple-echo echo-planar imaging [EPI]). Content analysis of the video and sound with 100 ms time resolution achieved relevant behavioral variables. These variables explained significant signal variance across large distributed networks. Occurrence of violent scenes revealed significant neuronal correlates in an event-related design. Activation of dorsal and deactivation of rostral anterior cingulate and amygdala characterized the mid-frontal pattern related to virtual violence. Statistics and effect sizes can be considered large at these areas. Optimized imaging strategies allowed for single-subject and for single-trial analysis with good image quality at basal brain structures. We propose that virtual environments can be used to study neuronal processes involved in semi-naturalistic behavior as determined by content analysis. Importantly, the activation pattern reflects brain-environment interactions rather than stimulus responses as observed in classical experimental designs. We relate our findings to the general discussion on social effects of playing first-person shooter games.


Effect of dutasteride in men receiving intermittent androgen ablation therapy: The AVIAS trial.
We studied the effect of dutasteride on the length of the off-treatment period in prostate cancer patients on intermittent androgen deprivation (IAD) therapy. We conducted a randomized, placebo-controlled Phase II trial in men with localized prostate cancer and a rising prostate-specific antigen (PSA) level post-primary treatment. Patients were randomized to dutasteride (0.5 mg/day) or placebo. All patients received androgen deprivation therapy (ADT), which was stopped at month 9 if the PSA level was <1.0 ng/mL. ADT was resumed when PSA increased to ≥5.0 ng/mL. End points included time off treatment, PSA nadir after 9 months of ADT, serum testosterone and dihydrotestosterone levels, and time to castrate-resistant prostate cancer (rising PSA while testosterone levels remain <50 ng/mL). There were 87 evaluable patients: 49 dutasteride, 38 placebo. In total, 80 patients completed one treatment cycle: 45 dutasteride, 35 placebo. The median time off treatment for patients reaching ≥5 ng/mL was 18.6 and 16.7 months for dutasteride and placebo, respectively (p = 0.7600). The median PSA nadir at 9 months was 0.1 and 0.075 ng/mL, respectively (p = 0.4486). There were no cases of androgen-independent prostate cancer. Our study limitations include its short duration with only one treatment cycle evaluated. This small-scale Phase II randomized controlled trial showed no benefit to the addition of dutasteride to an IAD regimen.


Absolute distance measurement using frequency-sweeping heterodyne interferometer calibrated by an optical frequency comb.
We present a frequency-sweeping heterodyne interferometer to measure an absolute distance based on a frequency-tunable diode laser calibrated by an optical frequency comb (OFC) and an interferometric phase measurement system. The laser frequency-sweeping process is calibrated by the OFC within a range of 200 GHz and an accuracy of 1.3 kHz, which brings about a precise temporal synthetic wavelength of 1.499 mm. The interferometric phase measurement system consisting of the analog signal processing circuit and the digital phase meter achieves a phase difference resolution better than 0.1 deg. As the laser frequency is sweeping, the absolute distance can be determined by measuring the phase difference variation of the interference signals. In the laboratory condition, our experimental scheme realizes micrometer accuracy over meter distance.


Toll-like receptor genetic variations in bone marrow transplantation.
The Toll-like receptor family mediates the innate immune system through recognizing the molecular patterns of microorganisms and self-components and leading the synthesis of the inflammatory mediators. We retrospectively examined whether or not genetic variations in toll-like receptor 1 (rs5743551, -7202GQ>A), toll-like receptor 2 (rs7656411, 22215G>T), and toll-like receptor 4 (rs11536889, +3725G>C) affected transplant outcomes in a cohort of 365 patients who underwent unrelated HLA-matched bone marrow transplantation (for hematologic malignancies through the Japan Marrow Donor Program. Only donor toll-like receptor 4 variation significantly improved the survival outcomes. A multivariate analysis showed that the donor toll-like receptor 4 +3725G/G genotype was significantly associated with a better 5-year progression-free survival and a lower 5-year transplant-related mortality than other variations. Furthermore, the donor toll-like receptor 4 +3725G/G genotype was associated with a significantly lower incidence of fatal infections than other variations. The validation study of 502 patients confirmed that the donor toll-like receptor 4 +3725G/G genotype was associated with better survival outcomes. Toll-like receptor4 genotyping in transplant donors may therefore be a useful tool for optimizing donor selection and evaluating pretransplantation risks.


Dietary intake of carotenoids and retinol and endometrial cancer risk in an Italian case-control study.
To provide information on the relation between intake of carotenoids and retinol and endometrial cancer, since available data are inconsistent. Further, carotenoids other than beta-carotene have been rarely investigated. We conducted a multi-centric case-control study in various areas of Italy between 1992 and 2006 on 454 women with incident, histologically confirmed endometrial cancer and 908 controls admitted to the same network of hospitals of cases for acute, non-neoplastic conditions. Intake of carotenoids and retinol was computed from a validated and reproducible food frequency questionnaire. We adjusted for selected covariates, including energy intake, and calculated multivariate odds ratios (OR) and 95% confidence intervals (CI) using conditional logistic regression. Comparing the highest to the lowest quartile of intake, the ORs of endometrial cancer were 0.69 (95% CI, 0.48-0.99) for beta-carotene, 0.65 (95% CI, 0.45-0.94) for beta-cryptoxanthin, and 0.59 (95% CI, 0.41-0.85) for lutein plus zeaxanthin intake. No association emerged with retinol (OR = 1.31, 95% CI, 0.94-1.84), alpha-carotene (OR = 0.94, 95% CI, 0.66-1.34), and lycopene (OR = 0.95, 95% CI, 0.68-1.34). Our results support a favorable role of selected dietary carotenoids on endometrial cancer risk.


Identification of Atg2 and ArfGAP1 as Candidate Genetic Modifiers of the Eye Pigmentation Phenotype of Adaptor Protein-3 (AP-3) Mutants in Drosophila melanogaster.
The Adaptor Protein (AP)-3 complex is an evolutionary conserved, molecular sorting device that mediates the intracellular trafficking of proteins to lysosomes and related organelles. Genetic defects in AP-3 subunits lead to impaired biogenesis of lysosome-related organelles (LROs) such as mammalian melanosomes and insect eye pigment granules. In this work, we have performed a forward screening for genetic modifiers of AP-3 function in the fruit fly, Drosophila melanogaster. Specifically, we have tested collections of large multi-gene deletions--which together covered most of the autosomal chromosomes-to identify chromosomal regions that, when deleted in single copy, enhanced or ameliorated the eye pigmentation phenotype of two independent AP-3 subunit mutants. Fine-mapping led us to define two non-overlapping, relatively small critical regions within fly chromosome 3. The first critical region included the Atg2 gene, which encodes a conserved protein involved in autophagy. Loss of one functional copy of Atg2 ameliorated the pigmentation defects of mutants in AP-3 subunits as well as in two other genes previously implicated in LRO biogenesis, namely Blos1 and lightoid, and even increased the eye pigment content of wild-type flies. The second critical region included the ArfGAP1 gene, which encodes a conserved GTPase-activating protein with specificity towards GTPases of the Arf family. Loss of a single functional copy of the ArfGAP1 gene ameliorated the pigmentation phenotype of AP-3 mutants but did not to modify the eye pigmentation of wild-type flies or mutants in Blos1 or lightoid. Strikingly, loss of the second functional copy of the gene did not modify the phenotype of AP-3 mutants any further but elicited early lethality in males and abnormal eye morphology when combined with mutations in Blos1 and lightoid, respectively. These results provide genetic evidence for new functional links connecting the machinery for biogenesis of LROs with molecules implicated in autophagy and small GTPase regulation.


Palpebral and facial skin infestation by Demodex folliculorum.
To evaluate facial Demodex densities in participants with varying severities of blepharitis secondary to Demodex folliculorum assessed by the highest number of cylindrical dandruff on one lid. This double masked cross-sectional study included 58 participants [19 control, 21 mild/moderate and 18 severe Demodex blepharitis] who underwent a standardized skin-surface biopsy and a lash epilation for each lid to obtain the forehead Demodex densities and the overall lash mite count, respectively. Also, facial photographs were taken to evaluate facial erythema and dermatological conditions. The Ocular Surface Disease Index [OSDI], non-invasive break-up time [NIBUT], tear meniscus height [TMH], bulbar conjunctival redness as well as additional questions on watery eyes, ocular itching and itching along the lids were assessed. Both mild/moderate and severe Demodex blepharitis groups were over the cut-off value [≥ 5 mites/cm2] that confirms a facial demodicosis (mild/moderate: 5 ± 1; severe: 6 ± 1) while the control group was below it (2 ± 1). Thereby, group comparisons showed that an increased severity of Demodex blepharitis was associated with higher forehead mite densities (p = 0.002) and increased lash mite count (p < 0.001). The degree of facial erythema was also positively correlated with forehead mite densities (rs = 0.31, p = 0.02). When compared to the controls, the mild/moderate group had more watery eyes (X2 = 6.54, p = 0.02), a lower TMH (U = 100.5, p = 0.006) and the severe group had more itching along the lids (X2 = 4.94, p = 0.04). The other ocular signs and symptoms [NIBUT, bulbar conjunctival redness, OSDI] were not affected by the severity of Demodex blepharitis (p > 0.05). Palpebral and facial Demodex infestation can co-exist, as the presence of blepharitis secondary to Demodex is associated with increased facial mite densities.


MAPK-specific tyrosine phosphatases: new targets for drug discovery?
Protein tyrosine phosphatases (PTPs) have key roles in a diverse range of cellular processes, and their dysregulation is associated with several human diseases. Many PTPs are recognized as potential drug targets; however, inhibitor development has focused only on a small number of enzymes, most notably PTP1B for type II diabetes and obesity, and MKP1 and CDC25 for cancer. The future challenge of selective-inhibitor development for PTPs will be significantly facilitated by the recent rapid progress in the structural biology of the 'PTPome'. In this article, we focus on the family of mitogen-activated protein kinase (MAPK)-specific tyrosine phosphatases--PTPN5 [also called striatal-enriched phosphatase (STEP)], PTPN7 (also called hematopoietic PTP) and PTPRR (also called PC12 PTP or STEP-like PTP)--and discuss approaches for achieving selectivity for the MAPK-PTPs at the molecular level using recently determined high-resolution X-ray crystal structures. We believe that the development of specific inhibitors would provide a valuable set of experimental pharmacological tools for investigating the physiological role of these phosphatases and exploring their emerging role in human disease.


Ecosystem services provision by Mediterranean forests will be compromised above 2℃ warming.
Forests provide a wide range of provisioning, regulating and cultural services of great value to societies across the Mediterranean basin. In this study, we reviewed the scientific literature of the last 30 years to quantify the magnitude of projected changes in ecosystem services provision by Mediterranean forests under IPCC climate change scenarios. We classified the scenarios according to the temperature threshold of 2℃ set by the Paris Agreement (below or above). The review of 78 studies shows that climate change will lead to a general reduction in the provision of regulating services (e.g. carbon storage, regulation of freshwater quantity and quality) and a general increase in the number of fires, burnt areas and generally, an increase in climate-related forest hazards (median + 62% by 2100). Studies using scenarios above the 2℃ threshold projected significantly more negative changes in regulating services than studies using scenarios below this threshold. Main projected trend changes on material services (e.g. wood products), were less clear and depended on (i) whether or not the studies considered the interaction between the rise in temperatures and other drivers (e.g. forest management, CO2 fertilization) and (ii) differences in productivity responses across the tree species evaluated. Overall, the reviewed studies projected significant reductions in range extent and habitat suitability for the most drought-sensitive forest species (e.g. -88% Fagus sylvatica), while the amount of habitat available for more drought-tolerant species will remain stable or increase; however, the magnitude of projected change for these more xeric species was limited when high-end extreme climatic scenarios were considered (above Paris Agreement). Our review highlights the benefits that climate change mitigation (to keep global mean temperature increase <2℃) can bring in terms of service provision and conservation of Mediterranean forests.


Travel risk behaviors as a determinants of receiving pre-travel health consultation and prevention.
An estimated 30-60 % of travelers experience an illness while traveling. The incidence of travel-related illness can be reduced by preventive measures such as those provided by the Traveler Health Clinic (THC) in Kuwait. The present study is an analytical comparative study between groups of travelers visiting the THC during the study period (May 2009 - December 2010) and an age- and gender-matched control group of non-visitors (800 people). Both groups completed a modified pre-departure questionnaire. Bivariate analysis revealed that Kuwaitis (68.2 %), those traveling for work (25.3 %) or leisure (59.5 %), those living in camps (20.4 %) or hotels (64.0 %), and those with knowledge of the THC from the media (28.1 %) or other sources (57.3 %), were more likely to be associated with a high frequency of visits to the THC (p < 0.001). Additionally, travelers heading to Africa (47 %) and South America (10 %) visited the THC more than did others (P < 0.05). Multivariate analysis revealed that nationality, followed by purpose of travel, duration of stay, and choice of travel destination are independent predictors of receiving pre-travel consultation from the THC. Nationality, purpose of travel, length of stay, and travel destination are predictors for receiving a pre-travel consultation from the THC.


Conjunctival Neutrophils Predict Progressive Scarring in Ocular Mucous Membrane Pemphigoid.
Ocular mucous membrane pemphigoid (OcMMP) is a rare autoimmune disorder resulting in progressive conjunctival fibrosis and ocular surface failure leading to sight loss in up to 50%. This study was designed to optimize an ocular surface sampling technique for identification of novel biomarkers associated with disease activity and/or progressive fibrosis. Fifty-seven patients with OcMMP underwent detailed examination of conjunctival inflammation and fibrosis using fornix depth measurement. Ocular surface impression cytology (OSIC) to sample superior bulbar conjunctiva combined with flow cytometry (OSIC-flow) profiled infiltrating leukocytes. Profiles were compared with healthy controls (HC) and disease controls (primary Sjögren's syndrome, pSS). Thirty-five OcMMP patients were followed every 3 months for 12 months. Overall neutrophils were elevated in OcMMP eyes when compared to pSS or HC (109 [18%] neutrophils/impression [NPI]; 2 [0.2%]; 6 [0.8%], respectively [P < 0.0001]) and in OcMMP patients with no visible inflammation when compared with HC (44.3 [7.9%]; 5.8 [0.8%]; P < 0.05). At 12 months follow-up, 53% of OcMMP eyes progressed, and this was associated with baseline conjunctival neutrophilia (P = 0.004). As a potential biomarker, a value of 44 NPI had sensitivity, specificity, and positive predictive values of 75%, 70%, and 73%, respectively. Notably, eyes with no visible inflammation and raised conjunctival neutrophils were more likely to progress and have a greater degree of conjunctival shrinkage compared to those without raised neutrophils. These data suggest that OSIC-flow cytometric analyses may facilitate repeated patient sampling. Neutrophils may act as a biomarker for monitoring disease activity, progressive fibrosis, and response to therapy in OcMMP even when the eye appears clinically uninflamed.


Voltage-activated cation permeability in high-potassium but not low-potassium red blood cells.
We have recently reported that voltage-activated fluxes of Na, K, and Ca occur in human red blood cells [J.A. Halperin, C. Brugnara, M. Tosteson, T. Van Ha, and D. C. Tosteson. Am. J. Physiol. 257 (Cell Physiol. 26): C986-C996, 1989]. The cation permeability increases progressively as the membrane potential becomes more inside positive above +20 mV. In this paper we show that this effect also occurs in high-potassium (HK), but not in low-potassium (LK), sheep and dog red blood cells. This result suggests that the voltage-activated cation transport pathway is not the result of nonspecific dielectric breakdown of the lipid bilayer but, rather, relates to some membrane component, presumably a protein, that is expressed in HK human and sheep but not in LK sheep and dog red blood cells.


Morning sickness: a mechanism for protecting mother and embryo.
Approximately two-thirds of women experience nausea or vomiting during the first trimester of pregnancy. These symptoms are commonly known as morning sickness. Hook (1976) and Profet (1988) hypothesized that morning sickness protects the embryo by causing pregnant women to physically expel and subsequently avoid foods that contain teratogenic and abortifacient chemicals, especially toxic chemicals in strong-tasting vegetables, caffeinated beverages and alcohol. We examined this hypothesis by comprehensively reviewing the relevant medical, psychological and anthropological literature. In its support, (i) symptoms peak when embryonic organogenesis is most susceptible to chemical disruption (weeks 6-18), (ii) women who experience morning sickness are significantly less likely to miscarry than women who do not (9 of 9 studies), (iii) women who vomit suffer fewer miscarriages than those who experience nausea alone, and (iv) many pregnant women have aversions to alcoholic and nonalcoholic (mostly caffeinated) beverages and strong-tasting vegetables, especially during the first trimester. Surprisingly, however, the greatest aversions are to meats, fish, poultry, and eggs. A cross-cultural analysis using the Human Relations Area Files revealed 20 traditional societies in which morning sickness has been observed and seven in which it has never been observed. The latter were significantly less likely to have animal products as dietary staples and significantly more likely to have only plants (primarily corn) as staples than the 20 societies in which morning sickness occurred. Animal products may be dangerous to pregnant women and their embryos because they often contain parasites and pathogens, especially when stored at room temperatures in warm climates. Avoiding foodborne microorganisms is particularly important to pregnant women because they are immunosuppressed, presumably to reduce the chances of rejecting tissues of their own offspring (Haig 1993). As a result, pregnant women are more vulnerable to serious, often deadly infections. We hypothesize that morning sickness causes women to avoid foods that might be dangerous to themselves or their embryos, especially foods that, prior to widespread refrigeration, were likely to be heavily laden with microorganisms and their toxins. The alternative hypotheses that morning sickness is (i) an epiphenomenon of mother-offspring genetic conflict or hormones associated with viable pregnancies, or (ii) an indicator to potential sexual partners and kin that the woman is pregnant, resulting in reduced sexual behavior and increased nepotistic aid, were not well supported. Available data are most consistent with the hypothesis that morning sickness serves an adaptive, prophylactic function.


Combined mutation and copy-number variation detection by targeted next-generation sequencing in uveal melanoma.
Uveal melanoma is a highly aggressive cancer of the eye, in which nearly 50% of the patients die from metastasis. It is the most common type of primary eye cancer in adults. Chromosome and mutation status have been shown to correlate with the disease-free survival. Loss of chromosome 3 and inactivating mutations in BAP1, which is located on chromosome 3, are strongly associated with 'high-risk' tumors that metastasize early. Other genes often involved in uveal melanoma are SF3B1 and EIF1AX, which are found to be mutated in intermediate- and low-risk tumors, respectively. To obtain genetic information of all genes in one test, we developed a targeted sequencing method that can detect mutations in uveal melanoma genes and chromosomal anomalies in chromosome 1, 3, and 8. With as little as 10 ng DNA, we obtained enough coverage on all genes to detect mutations, such as substitutions, deletions, and insertions. These results were validated with Sanger sequencing in 28 samples. In >90% of the cases, the BAP1 mutation status corresponded to the BAP1 immunohistochemistry. The results obtained in the Ion Torrent single-nucleotide polymorphism assay were confirmed with several other techniques, such as fluorescence in situ hybridization, multiplex ligation-dependent probe amplification, and Illumina SNP array. By validating our assay in 27 formalin-fixed paraffin-embedded and 43 fresh uveal melanomas, we show that mutations and chromosome status can reliably be obtained using targeted next-generation sequencing. Implementing this technique as a diagnostic pathology application for uveal melanoma will allow prediction of the patients' metastatic risk and potentially assess eligibility for new therapies.


The chiral structure of porous chitin within the wing-scales of Callophrys rubi.
The structure of the porous three-dimensional reticulated pattern in the wing scales of the butterfly Callophrys rubi (the Green Hairstreak) is explored in detail, via scanning and transmission electron microscopy. A full 3D tomographic reconstruction of a section of this material reveals that the predominantly chitin material is assembled in the wing scale to form a structure whose geometry bears a remarkable correspondence to the srs net, well-known in solid state chemistry and soft materials science. The porous solid is bounded to an excellent approximation by a parallel surface to the Gyroid, a three-periodic minimal surface with cubic crystallographic symmetry I4₁32, as foreshadowed by Stavenga and Michielson. The scale of the structure is commensurate with the wavelength of visible light, with an edge of the conventional cubic unit cell of the parallel-Gyroid of approximately 310 nm. The genesis of this structure is discussed, and we suggest it affords a remarkable example of templating of a chiral material via soft matter, analogous to the formation of mesoporous silica via surfactant assemblies in solution. In the butterfly, the templating is achieved by the lipid-protein membranes within the smooth endoplasmic reticulum (while it remains in the chrysalis), that likely form cubic membranes, folded according to the form of the Gyroid. The subsequent formation of the chiral hard chitin framework is suggested to be driven by the gradual polymerisation of the chitin precursors, whose inherent chiral assembly in solution (during growth) promotes the formation of a single enantiomer.


Extracorporeal Membrane Oxygenation for Hemophagocytic Lymphohistiocytosis.
BACKGROUND Hemophagocytic lymphohistiocytosis (HLH) is a rare hematological disease characterized by an excessive inflammatory response to various triggers, resulting in rapid multi-organ failure. Its incidence may be underestimated due to its rarity, its variable clinical presentation, and its high mortality rate prior to diagnosis. Oftentimes, HLH is mistaken for refractory sepsis and improperly treated as such. Left untreated, the disease is universally fatal. With treatment, case series of adults with HLH report a 30-day mortality of up to 44% and an overall mortality of up to 75%. CASE REPORT We describe the use of extracorporeal membrane oxygenation (ECMO) in a previously healthy young man with HLH and acute respiratory distress syndrome (ARDS), a common sequela of HLH. ECMO was employed to provide temporary hemodynamic support, allowing for recovery of pulmonary function compromised during the initial cytokine storm. Additionally, and perhaps more importantly, implementation of ECMO provided the time necessary for the eventual diagnosis and treatment of HLH. CONCLUSIONS Although limited case reports and case series suggest that the use of ECMO in pediatric patients with HLH is associated with high mortality, our experience suggests that ECMO should not be rejected as a supportive modality in adults with HLH who have potentially recoverable cardiopulmonary function. We believe that ECMO may be appropriately instituted in select patients with HLH, or in rapidly deteriorating patients with an unknown illness refractory to conventional therapy, to allow for end-organ recovery, to reach a diagnosis, and to administer appropriate therapy.


Heart rate variability in familial Mediterranean fever patients.
Familial Mediterranean fever (FMF) is an autosomal recessive autoimmune disease, presenting with the attacks of fever and inflammation of serous membranes. One of the leading causes of death in autoimmune rheumatologic diseases is cardiovascular events. The purpose of this study is to evaluate the effects of FMF on the autonomic nerve and cardiovascular systems by measuring the indices of heart rate variability (HRV). Thirty FMF patients and the same number of healthy volunteers were enrolled to the study. Standard deviation of all R-R intervals (SDNN), the square root of the sum of the square of the differences between successive R-R intervals (RMSSD), standard deviation of 5-minute mean values of R-R interval (SDANN), low frequency (LF), and high frequency (HF) were measured. Time domain indices (SDNN, SDANN, and RMSSD) were: 124.67±40.79, 129.87±36.43 (p=0.605); 11.43±38.41, 11.23±38.98 (p=0.984); and 33.43±17.39, 38.17±12.8 (p=0.235) for FMF patients and controls, respectively, and similar in both groups. Frequency domain indices (HF, LF, and LF/HF) were: 290.41±290.25, 322.20±222.54 (p=0.639); 596.16±334.07, 805.80±471.00 (p=0.051); and 3.57±2.57, 3.05±1.40 (p=0.338) for FMF patients and controls, respectively, and similar in both groups. The HRV parameters were similar in both groups. However, studies including larger populations and using different methods are required to clarify if autonomic dysfunction exists in patients with FMF.


Incidence, impact and indicators of difficult intubations in the neonatal intensive care unit: a report from the National Emergency Airway Registry for Neonates.
To determine the incidence, indicators and clinical impact of difficult tracheal intubations in the neonatal intensive care unit (NICU). Retrospective review of prospectively collected data on intubations performed in the NICU from the National Emergency Airway Registry for Neonates. Ten academic NICUs. Neonates intubated in the NICU at each of the sites between October 2014 and March 2017. Difficult intubation was defined as one requiring three or more attempts by a non-resident provider. Patient (age, weight and bedside predictors of difficult intubation), practice (intubation method and medications used), provider (training level and profession) and outcome data (intubation attempts, adverse events and oxygen desaturations) were collected for each intubation. Out of 2009 tracheal intubations, 276 (14%) met the definition of difficult intubation. Difficult intubations were more common in neonates <32 weeks, <1500 g. The difficult intubation group had a 4.9 odds ratio (OR) for experiencing an adverse event and a 4.2 OR for severe oxygen desaturation. Bedside screening tests of difficult intubation lacked sensitivity (receiver operator curve 0.47-0.53). Difficult intubations are common in the NICU and are associated with adverse event and severe oxygen desaturation. Difficult intubations occur more commonly in small preterm infants. The occurrence of a difficult intubation in other neonates is hard to predict due to the lack of sensitivity of bedside screening tests.


In vitro cytopathic effects of a cysteine protease of Tritrichomonas foetus on cultured bovine uterine epithelial cells.
To evaluate the cytopathic effects of Tritrichomonas foetus and a purified cysteine protease (ie, CP30) of T foetus on cultured bovine uterine epithelial cells (BUECs) in vitro. 10 reproductive tracts were obtained from late-term bovine fetuses at a commercial abattoir. An in vitro culture system of BUECs was developed to study the cytopathic effects of T foetus and purified CP30 of T foetus on host cells. Cytotoxicity of T foetus or CP30 on exposed BUECs was determined. Fluorescence microscopy and flow cytometry analyses were used to detect apoptosis. A fluorometric assay was used to detect BUEC caspase 3 activation. The CP inhibitor E-64 and a caspase inhibitor were used to inhibit apoptosis. Cytopathic effects were observed in BUECs treated with parasites or CP30 and were concentration and time dependent. The BUECs underwent apoptosis in the presence of parasites or CP30. The specific CP inhibitor E-64 abolished the induction of apoptosis in BUECs by CP30. The caspase inhibitor reduced the amount of apoptosis in BUECs. T foetus and its CP30 induce apoptosis in cultured BUECs in vitro. Induction of apoptosis by CP30 is correlated with protease activity. Endometrial cell death as a result of a T foetus infection is likely to be more important in mediating infertility than a direct effect on the conceptus. Provoking an apoptotic reaction in the host may mitigate an inflammatory reaction or immune response and therefore favor survival of the parasite in a chronic infection.


A glycosylphosphatidylinositol protein anchor from procyclic stage Trypanosoma brucei: lipid structure and biosynthesis.
Cells of the insect (procyclic) stage of the life cycle of the African trypanosome, Trypanosoma brucei, express an abundant stage-specific glycosylated phosphatidylinositol (GPI) anchored glycoprotein, the procyclic acidic repetitive protein (PARP). The anchor is insensitive to the action of bacterial phosphatidylinositol-specific phospholipase C (PI-PLC), suggesting that it contains an acyl-inositol. We have recently described the structure of a PI-PLC resistant glycosylphosphatidylinositol, PP1, which is specific to the procyclic stage, and have presented preliminary evidence that the phosphatidylinositol portion of the protein-linked GPI on PARP has a similar structure. In this paper we show, by metabolic labelling with [3H]fatty acids, that the PARP anchor contains palmitate esterified to inositol, and stearate at sn-1, in a monoacylglycerol moiety, a structure identical to PP1. Using pulse-chase labelling, we show that both fatty acids are incorporated into the GPI anchor from a large pool of metabolic precursors, rather than directly from acyl-CoA. We also demonstrate that the addition of the GPI anchor moiety to PARP is dependent on de novo protein synthesis, excluding the possibility that incorporation of fatty acids into PARP can occur by a remodelling of pre-existing GPI anchors. Finally we show that the phosphatidylinositol (PI) species that are utilized for GPI biosynthesis are a subpopulation of the cellular PI molecular species. We propose that these observations may be of general validity since several other eukaryotic membrane proteins (e.g. human erythrocyte acetylcholine esterase and decay accelerating factor) have been reported to contain palmitoylated inositol residues.


Obesity and nosocomial infections.
The prevention of healthcare-associated infections (HCAIs) is a major goal in modern healthcare. Intrinsic, patient-related factors may contribute to the risk of HCAIs. To review the association between obesity and the risk and outcome of HCAIs. A PubMed search of relevant studies on obesity and nosocomial infections and obesity and dosing of antimicrobials. Search terms were: 'obesity', 'infection', 'nosocomial infection', 'surgical site infection', 'critical care unit', 'bacteremia', 'urinary tract infection', 'health care associated infection'. Obesity has been shown to be associated with an increased risk of HCAIs in several studies. The association is most clear in cardiac, vascular, orthopaedic and gastrointestinal surgery. Body mass index (BMI) data are frequently recorded in patients undergoing surgical and invasive procedures. The recording of BMI data is not systematic in the literature and in many studies median BMI of the control group or reference group (normal weight) also indicates overweight or obesity. Thus, clear BMI cut-offs for increased infection risk cannot be determined. Obesity is frequently associated with underdosing of antimicrobials in both prophylaxis and treatment of HCAIs. Studies indicate that obesity affects the pharmacokinetics of antimicrobial drugs. However, there are no dosing recommendations for antimicrobial use in obesity. Obesity increases the risk of nosocomial infections and is frequently associated with underdosing of antimicrobials in both prophylaxis and treatment of HCAIs. A challenge in future hospital hygiene prevention lies in our capacity to combat obesity epidemics.


Cereal-based oral rehydration therapy. II. Strategic issues for its implementation in national diarrheal disease control programs.
Field studies in Bangladesh demonstrated that after proper training, village mothers were able to prepare and use rice-based, salt-enriched oral rehydration solutions containing safe concentrations of sodium, and were capable of achieving significantly fewer treatment failures and a reduction in the duration of diarrhea than with glucose-based oral rehydration solutions (ORS). An additional longitudinal study showed that improved growth and weight gain occurred with the consistent use of ORS; the effect was greater when rice-based ORS were used. In addition, the following possible limitations and benefits of cereal-based oral rehydration therapy, which are relevant to the strategies for its implementation in national diarrheal disease control programs, are discussed: safety, osmolarity, hypernatremia, spoiling, effectiveness, rehydration ability, reduction in diarrhea volume and duration, nutritional effects, effect on food intake, acceptance and usage by care givers, training of health workers, self-reliance of families, effect on other child survival activities, costs, potential problems in changing to cereal-based ORS, and the role of industrial production in packaged cereal-based ORS.


BET Bromodomain Inhibitors Enhance Efficacy and Disrupt Resistance to AR Antagonists in the Treatment of Prostate Cancer.
Next-generation antiandrogen therapies, such as enzalutamide and abiraterone, have had a profound impact on the management of metastatic castration-resistant prostate cancer (mCRPC). However, mCRPC patients invariably develop resistance to these agents. Here, a series of clonal cell lines were developed from enzalutamide-resistant prostate tumor xenografts to study the molecular mechanism of resistance and test their oncogenic potential under various treatment conditions. Androgen receptor (AR) signaling was maintained in these cell lines, which acquired potential resistance mechanisms, including expression of AR-variant 7 (AR-v7) and glucocorticoid receptor. BET bromodomain inhibitors were shown previously to attenuate AR signaling in mCRPC; here, we demonstrate the efficacy of bromodomain and extraterminal (BET) inhibitors in enzalutamide-resistant prostate cancer models. AR antagonists, enzalutamide, and ARN509 exhibit enhanced prostate tumor growth inhibition when combined with BET inhibitors, JQ1 and OTX015, respectively. Taken together, these data provide a compelling preclinical rationale to combine BET inhibitors with AR antagonists to subvert resistance mechanisms. Therapeutic combinations of BET inhibitors and AR antagonists may enhance the clinical efficacy in the treatment of mCRPC. http://mcr.aacrjournals.org/content/molcanres/14/4/324/F1.large.jpg


Recognizing human-object interactions in still images by modeling the mutual context of objects and human poses.
Detecting objects in cluttered scenes and estimating articulated human body parts from 2D images are two challenging problems in computer vision. The difficulty is particularly pronounced in activities involving human-object interactions (e.g., playing tennis), where the relevant objects tend to be small or only partially visible and the human body parts are often self-occluded. We observe, however, that objects and human poses can serve as mutual context to each other-recognizing one facilitates the recognition of the other. In this paper, we propose a mutual context model to jointly model objects and human poses in human-object interaction activities. In our approach, object detection provides a strong prior for better human pose estimation, while human pose estimation improves the accuracy of detecting the objects that interact with the human. On a six-class sports data set and a 24-class people interacting with musical instruments data set, we show that our mutual context model outperforms state of the art in detecting very difficult objects and estimating human poses, as well as classifying human-object interaction activities.


Proactive Control of Petri Disease of Grapevine Through Treatment of Propagation Material.
Petri disease is a vascular disease associated with decline and dieback of young grapevines. A major means of spread of the causal organisms, Phaeomoniella chlamydospora and Phaeoacremonium spp., is via infected propagation material. Since no curative control measures are known, proactive measures must be taken in grapevine nurseries to manage this disease. To study this aspect, semicommercial trials with naturally infected rootstock material were performed in grapevine nurseries in South Africa. Prior to grafting, rootstocks were treated as follows: 1-h drench in suspensions of benomyl, phosphoric acid, different bacterial and Trichoderma formulations, water, or hot water treated (HWT; 30 min at 50°C). Grafted cuttings were planted and grown in a greenhouse and two commercial field nurseries and uprooted 8 months later. In instances where rootstocks were treated with benomyl or Trichoderma formulations, the incidences of Phaeomoniella and Phaeoacremonium in grafted cuttings and uprooted nursery vines were significantly lower than that of the water treatment. However, the reduction was most consistent and noteworthy in vines on rootstocks that received HWT prior to grafting. HWT of dormant nursery vines effected a similar reduction in Phaeomoniella and Phaeoacremonium incidence. Root-stock drenches in benomyl and/or Trichoderma formulations could thus be integrated with HWT for the proactive management of Petri disease in grapevine nurseries.


MiR-152-5p as a microRNA passenger strand special functions in human gastric cancer cells.
Gastric cancer (GC) is one of the most common malignancies with high mortality rate. MiR-152 may exert the function of tumor suppressor by regulating its target gene, including PIK3CA. Nevertheless, all of the described functions are referred explicitly to miR-152-3p, while miR-152-5p as a passenger strand is poorly realized and entirely ignored. We previously selected miR-152-5p as a candidate using cell migration inhibition screening for GC cells and predicted that miR-152-5p might also target PIK3CA. In this study, we found an abnormal proportion of miR-152-3p / miR-152-5p in GC (gastric cancer) tissues and cells and demonstrated that miR-152-5p had poorer stability in GC cells, revealing the possibility that miR-152-5p is abnormally "suppressed" in gastric cancer. We also investigated and confirmed the role of miR-152-5p in GC by a series of experiments, and found that miR-152-5p modulated cell viability, migration, invasion, and cell-cycle progression of human GC cells, and also inhibited tumor growth and metastasis in vivo partially by targeting PIK3CA. More interestingly, it was proved that miR-152-3p and miR-152-5p had synergistic effects on the inhibition of PIK3CA in GC cells. The results of this study suggest that miR-152-5p may act as a tumor suppressor in SGC-7901 gastric cancer cells via targeting PIK3CA. Further, the study provides a novel insight into the roles of miRNA* during carcinogenesis.


An ethnically sensitive and gender-specific HIV/AIDS assessment of African American women: a comparative study of urban and rural American communities.
A prevention program that promotes attitudinal and behavioral change has been repeatedly recommended as an effective measure for community prevention and control of HIV/AIDS. Within the past decade, disease control programs among African Americans have shown no significant changes, as HIV/AIDS and related infections continue as the leading causes of death and disability in this population. It is particularly acute among African American females who, although representing only 13.9% of the United States female population, presently account for over 60% of all AIDS cases among females in the United States. The epidemic nature of the disease in this group poses the issue of African American women's rights and underscores their physical, emotional and sociocultural vulnerability to HIV/AIDS. This study used an open-ended attitude, knowledge, feelings, and behavior questionnaire (AKFBQ) survey approach to assess knowledge and various HIV/AIDS high-risk attitudinal and behavioral factors that affect the incidence, mortality, and morbidity of HIV/AIDS among women in specific urban centers and rural communities in the United States. Data analysis showed no differences in factors favoring rate of infection and level of spread of HIV/AIDS among the women in both the urban and rural communities. Although level of knowledge was higher among the urban subjects than rural ones, their beliefs, attitude/feelings, and potential for behavioral change did not differ significantly among women in the two communities. This article advocates both an ethnically sensitive and gender-specific HIV/AIDS intervention program for African American women and a more active involvement in and participation of African American leaders, parents, and faith-based communities in AIDS control efforts for African Americans.


Forty-Five Years of Duchenne Muscular Dystrophy in The Netherlands.
Duchenne muscular dystrophy (DMD) is a progressive muscle disease. No curative therapy is currently available, but in recent decades standards of care have improved. These improvements include the use of corticosteroids and mechanical ventilation. To present a detailed population based report of the DMD disease course in The Netherlands (1980-2006) and evaluate the effect of changes in care by comparing it with an historical Dutch DMD cohort (1961-1974). Information about DMD patients was gathered through the Dutch Dystrophinopathy Database using a standardized questionnaire and information from treating physicians. The study population involved 336 DMD patients (70% of the estimated prevalence), of whom 285 were still alive. Mean age at disease milestones was: diagnosis 4.3 years, wheelchair dependence 9.7 years, scoliosis surgery 14 years, cardiomyopathy (fractional shortening <27%) 15 years, mechanical ventilation 17 years and death 19 years. Within our cohort, corticosteroid use was associated with an increased age of wheelchair dependence from 9.8 to 11.6 years (p < 0.001). When comparing the recent cohort to the historical cohort, mean survival improved from 17 to 27 years (p < 0.001). The current study gives detailed information about the disease course of DMD patients, provides evidence for the positive effect of steroid treatment and mechanical ventilation and supports the use of patient registries as a valuable resource for evaluating improvements in care.


Struggling for dignity: the meaning of women's experiences of living with fibromyalgia.
Fibromyalgia (FM) is a common chronic pain syndrome with an obscure etiology, which mostly afflicts middle-aged women. In this study, 14 women with FM were interviewed about the meaning of living with the illness. A phenomenological-hermeneutic method was used to analyze and interpret the interview texts. The findings show that being a woman with FM means living a life greatly influenced by the illness in various ways. The women's experiences of living with FM were presented in three major interlaced themes: loss of freedom, threat to integrity, and a struggle to achieve relief and understanding. This study highlights the importance of meeting people suffering in illness with respect for their human dignity. The care of women with FM must empower the women to bring to bear their own resources so that they can manage to live with the illness.


Strongylocentrotus purpuratus spindle tubulin. I. Characteristics of its polymerization and depolymerization in vitro.
Tubulin was extracted from spindles isolated from embryos of the sea urchin Strongylocentrotus purpuratus, repolymerized in vitro, and purified through three cycles of temperature-dependent assembly and disassembly. In addition to the tubulin, these preparations contain a protein of 80 kdaltons and a small but variable amount of actin. At 37 degrees C, the tubulin polymerizes with a critical concentration of 0.15-0.2 mg/ml into smooth-walled polymers which contain predominantly 14 protofilaments. Removal of the 80 kdalton protein and the actin by DEAE-chromatography does not change the critical concentration for polymerization. At 15 degrees C, which is within the range of physiological temperatures for S. purpuratus embryos, the spindle tubulin will self-assemble, but the rate of total polymer formation is very slow, requiring hours in the test tube. This rate can be increased by shearing the polymerizing microtubules, creating more ends for assembly, indicating that the slow rate of polymer formation is due to a slow rate of self-initiation. If spindle tubulin is polymerized at 37 degrees C and then lowered to 15 degrees C, some polymer will be retained, the percentage of which depends on the protein concentration. These results demonstrate that spindle tubulin from S. purpuratus will assemble at 37 degrees C with a low critical concentration for polymerization in the absence of detectable MAPs and will self-assemble and maintain steady state levels of polymer at physiological temperatures.


Cohort study of occupational risk factors of low back pain in construction workers.
To identify work related risk factors of future low back pain (LBP) in a cohort of construction workers free of LBP at the start of follow up. The Hamburg construction worker study comprises 571 male construction workers who have undergone two comprehensive interview and physical examination surveys. A cohort of 285 subjects without LBP at baseline was identified. After a follow up of 3 years, the 1 year prevalence of self reported LBP was determined in the 230 men followed up (80.7%). Prevalence ratios (PRs) with 95% confidence intervals (95% CIs) of LBP at follow up according to self reported work tasks of construction workers measured at baseline were estimated from Cox's regression models which were adjusted for age, and anthropometric measures. At follow up 71 out of 230 workers (30.9%) reported LBP during the preceding 12 months. Four work tasks (scaffolding, erecting roof structures, sawing wood, laying large sandstones) with an increased risk of 1 year prevalence of LBP at follow up were further evaluated. After further adjustment for occupation the relative risk was increased for workers who had reported > or = 2 hour/shifts laying large sandstones (PR = 2.6; 95% CI 1.1 to 6.5). Work load of bricklayers was additionally estimated by an index on stone load (high exposure: PR = 4.0; 95% CI 0.8 to 19.8), and an index for laying huge bricks/blocks (yes/no: PR = 1.7; 95% CI 0.5 to 5.7). The results suggest that self reported differences in brick characteristics (size and type of stone) and temporal aspects of the work of bricklayers (average hours per shift laying specified stones) can predict the future prevalence of LBP. The data have to be interpreted with caution because multiple risk factors were tested.


Combat dermatology: the prevalence of skin disease in a deployed dermatology clinic in Iraq.
Since July 2004, the United States (U.S.) Army has operated a forward-deployed dermatology clinic in Baghdad, Iraq. This paper outlines the prevalence of skin disease among deployed service men and women in Operation Iraqi Freedom. A cross-sectional study was performed for all dermatology visits presenting to the Combat Dermatology Clinic, Ibn Sina, Iraq, between January 15, 2008 and July 15, 2008. In the six-month period reviewed, 2,696 total patients were evaluated. The most prevalent diagnoses included eczematous dermatitis [17%, n=462] and benign neoplasms [14%, n=375]. Eight percent (n=205) of the total visits were for skin cancer. This included: basal cell carcinoma, squamous cell carcinoma both in-situ and invasive, mycosis fungoides and melanoma. Actinic keratosis comprised 5% of the total visits (n=129). Bacterial infections comprised 6% (n=158) of the total visits and 31 of these cases were community acquired methicillin resistant Staphylococcus aureus (MRSA). Cross-sectional study with referral bias. This is the largest publication of the prevalence of skin disease in an exclusively dermatologic clinic in a combat setting. For the first time the presence of skin cancer is noted in a combat setting. The prevalence of MRSA is noted and was exclusively seen in U.S. soldiers. There was a statistically significant rise in the prevalence of eczematous dermatitides when compared with previous conflicts. Dermatologists can have a significant and strategic impact on deployed military medicine.


Longitudinal changes in brain magnetic resonance imaging findings in children with sickle cell disease.
Children with sickle cell anemia (HbSS) are at high risk for neurologically overt cerebral infarcts associated with stroke and neurologically silent cerebral infarcts correlated with neuropsychometric deficit. We used complete magnetic resonance imaging (MRI) histories from 266 HbSS children, aged 6 through 19 years, who were enrolled in the Cooperative Study of Sickle Cell Disease (CSSCD) to examine silent infarct prevalence, localization, recurrence, and progression. We report a baseline prevalence of 21.8%, marginally higher than previously reported due to improved imaging technologies. Although we observed no overall sex difference in prevalence, most lesions in girls occurred before age 6, whereas boys remained at risk until age 10. Silent infarcts were significantly smaller and less likely to be found in the frontal or parietal cortex than were infarcts associated with stroke. Children with silent infarct had an increased incidence of new stroke (1.03/100 patient-years) and new or more extensive silent infarct (7.06/100 patient-years) relative to stroke incidence among all children in our cohort (0.54/100 patient-years). Both events were substantially less frequent than the risk of stroke recurrence among children not provided chronic transfusion therapy. Although chronic transfusion is known to decrease occurrence of new silent infarcts and strokes in children with elevated cerebral arterial blood flow velocity, further study is required to determine its risk-benefit ratio in children with silent infarct and normal velocities. Until safe and effective preventive strategies against infarct recurrence are discovered, MRI studies are best reserved for children with neurologic symptoms, neuropsychometric deficits, or elevated cerebral artery velocities.


Induction and maintenance of regulatory T cells by transcription factors and epigenetic modifications.
Regulatory T cells (Tregs) are an essential cell subset for the maintenance of immune homeostasis. Foxp3 (Forkhead box P3) is the Treg master gene which is essential for immune suppressing activity. In addition, Tregs are characterized by a distinct pattern of gene expression, including upregulation of immune-suppressive genes and silencing of inflammatory genes. The molecular mechanisms of Treg development and maintenance have been intensively investigated. Tregs are characterized by expression of the transcription factor Foxp3. Several intronic enhancers and a promoter at the Foxp3 gene locus were shown to play important roles in Treg differentiation. The enhancers have been designated as conserved non-coding sequences (CNSs) 0, 1, 2, and 3. We showed that the transcription factors Nr4a and Smad2/3 are essential for the development of thymic Tregs and induced Tregs, respectively. Recently, Treg-specific DNA demethylation has been shown to play an important role in Treg stability. DNA demethylation of CNS2 has been implicated in Treg stability, and recent reports have revealed that the ten-eleven translocation (Tet) family of demethylation factor plays an important role in CpG demethylation at CNS2. This article reviews the recent progress on the roles of transcription factors and epigenetic modifications in the differentiation, maintenance, and function of Tregs.


Failure of clindamycin to eradicate infection with beta-hemolytic streptococci inducibly resistant to clindamycin in an animal model and in human infections.
Inducible clindamycin resistance in beta-hemolytic streptococci remains an underrecognized phenomenon of unknown clinical significance. We performed an evaluation of inducible clindamycin resistance using an animal model as well as retrospectively reviewing the charts of patients treated with clindamycin monotherapy who were infected with beta-hemolytic streptococci inducibly resistant to clindamycin. The neutropenic mouse thigh model of infection was used to evaluate the in vivo activity of clindamycin against beta-hemolytic streptococci, including isolates susceptible, inducibly resistant, or constitutively resistant to clindamycin. The clinical microbiology laboratory information system and pharmacy databases were cross-referenced to identify patients with infections due to inducibly clindamycin-resistant beta-hemolytic streptococci who were treated with clindamycin monotherapy. Medical records of these patients were reviewed to evaluate microbiologic and clinical outcomes. Inducible clindamycin resistance resulted in impaired killing of beta-hemolytic streptococci in the animal model. Though suppressed initially, compared to those with constitutive resistance (P=0.0429), by 48 h, colony counts of inducibly clindamycin-resistant organisms were similar to those of constitutively resistant isolates (P=0.1142). In addition, we identified 8 patients infected with inducibly clindamycin-resistant beta-hemolytic streptococci who experienced clinical and microbiologic failure when treated with clindamycin monotherapy. These patients either improved initially and subsequently failed or never responded to clindamycin therapy. We have demonstrated in a murine model of infection and from human cases that inducible clindamycin resistance in beta-hemolytic streptococci is clinically significant. Routine testing and reporting by clinical laboratories should be encouraged and alternative antimicrobial agents considered when these organisms are encountered in clinical care.


Identification of symbiotically defective mutants of Lotus japonicus affected in infection thread growth.
During the symbiotic interaction between legumes and rhizobia, the host cell plasma membrane and associated plant cell wall invaginate to form a tunnel-like infection thread, a structure in which bacteria divide to reach the plant root cortex. We isolated four Lotus japonicus mutants that make infection pockets in root hairs but form very few infection threads after inoculation with Mesorhizobium loti. The few infection threads that did initiate in the mutants usually did not progress further than the root hair cell. These infection-thread deficient (itd) mutants were unaffected for early symbiotic responses such as calcium spiking, root hair deformation, and curling, as well as for the induction of cortical cell division and the arbuscular mycorrhizal symbiosis. Complementation tests and genetic mapping indicate that itd2 is allelic to Ljsym7, whereas the itdl, itd3, and itd4 mutations identified novel loci. Bacterial release into host cells did occur occasionally in the itdl, itd2, and itd3 mutants suggesting that some infections may succeed after a long period and that infection of nodule cells could occur normally if the few abnormal infection threads that were formed reached the appropriate nodule cells.


Clinical protein science in translational medicine targeting malignant melanoma.
Melanoma of the skin is the sixth most common type of cancer in Europe and accounts for 3.4% of all diagnosed cancers. More alarming is the degree of recurrence that occurs with approximately 20% of patients lethally relapsing following treatment. Malignant melanoma is a highly aggressive skin cancer and metastases rapidly extend to the regional lymph nodes (stage 3) and to distal organs (stage 4). Targeted oncotherapy is one of the standard treatment for progressive stage 4 melanoma, and BRAF inhibitors (e.g. vemurafenib, dabrafenib) combined with MEK inhibitor (e.g. trametinib) can effectively counter BRAFV600E-mutated melanomas. Compared to conventional chemotherapy, targeted BRAFV600E inhibition achieves a significantly higher response rate. After a period of cancer control, however, most responsive patients develop resistance to the therapy and lethal progression. The many underlying factors potentially causing resistance to BRAF inhibitors have been extensively studied. Nevertheless, the remaining unsolved clinical questions necessitate alternative research approaches to address the molecular mechanisms underlying metastatic and treatment-resistant melanoma. In broader terms, proteomics can address clinical questions far beyond the reach of genomics, by measuring, i.e. the relative abundance of protein products, post-translational modifications (PTMs), protein localisation, turnover, protein interactions and protein function. More specifically, proteomic analysis of body fluids and tissues in a given medical and clinical setting can aid in the identification of cancer biomarkers and novel therapeutic targets. Achieving this goal requires the development of a robust and reproducible clinical proteomic platform that encompasses automated biobanking of patient samples, tissue sectioning and histological examination, efficient protein extraction, enzymatic digestion, mass spectrometry-based quantitative protein analysis by label-free or labelling technologies and/or enrichment of peptides with specific PTMs. By combining data from, e.g. phosphoproteomics and acetylomics, the protein expression profiles of different melanoma stages can provide a solid framework for understanding the biology and progression of the disease. When complemented by proteogenomics, customised protein sequence databases generated from patient-specific genomic and transcriptomic data aid in interpreting clinical proteomic biomarker data to provide a deeper and more comprehensive molecular characterisation of cellular functions underlying disease progression. In parallel to a streamlined, patient-centric, clinical proteomic pipeline, mass spectrometry-based imaging can aid in interrogating the spatial distribution of drugs and drug metabolites within tissues at single-cell resolution. These developments are an important advancement in studying drug action and efficacy in vivo and will aid in the development of more effective and safer strategies for the treatment of melanoma. A collaborative effort of gargantuan proportions between academia and healthcare professionals has led to the initiation, establishment and development of a cutting-edge cancer research centre with a specialisation in melanoma and lung cancer. The primary research focus of the European Cancer Moonshot Lund Center is to understand the impact that drugs have on cancer at an individualised and personalised level. Simultaneously, the centre increases awareness of the relentless battle against cancer and attracts global interest in the exceptional research performed at the centre.


Body size and prostate cancer: a population-based case-control study in China.
We conducted a population-based case-control study in China to investigate whether body size plays a role in prostate cancer etiology and whether it can explain the rapid increase in prostate cancer incidence rates in China. A total of 238 cases newly diagnosed with primary prostate cancer in Shanghai, China, during 1993-1995 were included in the study. Four hundred and seventy-one healthy control subjects were randomly selected from among residents of Shanghai and frequency-matched to cases on the basis of age. In-person interviews were conducted to elicit information on height, weight history, and other lifestyle factors. Waist and hip circumferences were measured at interview. Odds ratios (ORs) were used to measure the association between prostate cancer and anthropometric variables including height, weight, body mass index (BMI), waist, hip, and right upper arm circumferences, and waist-to-hip ratio (WHR; an indicator of abdominal adiposity). High levels of WHR were related to an excess risk, with men in the highest quartile (WHR > 0.92) having an almost 3-fold risk (OR, 2.71; 95% CI = 1.66-4.41; Ptrend = 0.0001) compared with men in the lowest quartile (WHR < 0.86). In contrast, men in the highest quartile of hip circumference (>97.4 cm) had a reduced risk (OR, 0.46; 95% CI = 0.29-0.74; Ptrend = 0.0002) relative to men in the lowest quartile (<86 cm). No association was found for height, usual adult weight, or preadult and usual adult BMI. Our results suggest that even in a very lean population (average BMI = 21.9), abdominal adiposity may be associated with an increased risk of clinical prostate cancer, pointing to a role of hormones in prostate cancer etiology. Additional research is needed to confirm these findings in prospective studies, especially in Western populations where abdominal obesity is much more common, and to clarify the underlying hormonal mechanisms involved.


Secondary solid cancer screening following hematopoietic cell transplantation.
Hematopoietic stem cell transplant (HCT) recipients have a substantial risk of developing secondary solid cancers, particularly beyond 5 years after HCT and without reaching a plateau overtime. A working group was established through the Center for International Blood and Marrow Transplant Research and the European Group for Blood and Marrow Transplantation with the goal to facilitate implementation of cancer screening appropriate to HCT recipients. The working group reviewed guidelines and methods for cancer screening applicable to the general population and reviewed the incidence and risk factors for secondary cancers after HCT. A consensus approach was used to establish recommendations for individual secondary cancers. The most common sites include oral cavity, skin, breast and thyroid. Risks of cancers are increased after HCT compared with the general population in skin, thyroid, oral cavity, esophagus, liver, nervous system, bone and connective tissues. Myeloablative TBI, young age at HCT, chronic GVHD and prolonged immunosuppressive treatment beyond 24 months were well-documented risk factors for many types of secondary cancers. All HCT recipients should be advised of the risks of secondary cancers annually and encouraged to undergo recommended screening based on their predisposition. Here we propose guidelines to help clinicians in providing screening and preventive care for secondary cancers among HCT recipients.


High concentrations of antibodies to xanthine oxidase in human and animal sera. Molecular characterization.
The widespread occurrence of antibodies (IgG) specific to xanthine oxidase in both normal (nonimmune) human and animal sera, and in antisera raised against a diversity of unrelated antigens is described. A study of sera from 81 humans revealed that xanthine oxidase-specific IgG represents a high proportion (1-8%) of total IgG. No obvious correlation to pathological events or symptoms of disease could be found. These xanthine oxidase-specific antibodies could be isolated by immunoaffinity chromatography on purified human or bovine xanthine oxidase and showed specific binding to the enzyme polypeptide of Mr 155,000 in immunoblotting experiments. By immunofluorescence microscopy they displayed the same cell type-specific reaction as experimentally induced antibodies, i.e., the staining of lactating mammary gland epithelium and capillary endothelium. The naturally occurring xanthine oxidase-specific antibodies consisted of polyclonal IgG of various subclasses. F(ab')2 preparations gave immune-reactions identical to those of IgG. The human xanthine oxidase-specific IgG cross-reacted with the bovine enzyme and both human and animal antibodies partially inhibited its activity. The xanthine oxidase activity of human milk lipid globules and supernatant fractions from various human tissues was extremely low when compared with that of the bovine antigen. The enzyme protein, however, was effectively precipitated from these sources by both the human and bovine antibodies. We suggest that the exceptionally high concentrations of antibodies against one protein, xanthine oxidase, are due to self-immunization to the xanthine oxidase antigen present in endothelial cells of capillaries. We do not exclude, however, nutritional contributions of bovine milk antigen to the appearance of xanthine oxidase antibodies in human sera. The possible biological functions of this immunological reaction are discussed.


When words fail us: insights into language processing from developmental and acquired disorders.
Acquired disorders of language represent loss of previously acquired skills, usually with relatively specific impairments. In children with developmental disorders of language, we may also see selective impairment in some skills; but in this case, the acquisition of language or literacy is affected from the outset. Because systems for processing spoken and written language change as they develop, we should beware of drawing too close a parallel between developmental and acquired disorders. Nevertheless, comparisons between the two may yield new insights. A key feature of connectionist models simulating acquired disorders is the interaction of components of language processing with each other and with other cognitive domains. This kind of model might help make sense of patterns of comorbidity in developmental disorders. Meanwhile, the study of developmental disorders emphasizes learning and change in underlying representations, allowing us to study how heterogeneity in cognitive profile may relate not just to neurobiology but also to experience. Children with persistent language difficulties pose challenges both to our efforts at intervention and to theories of learning of written and spoken language. Future attention to learning in individuals with developmental and acquired disorders could be of both theoretical and applied value.


Monitoring small molecule diffusion into hydrogels at various temperatures by fluorescence technique.
Steady state fluorescence technique was used to study small molecule diffusion into polyacrylamide (PAAm) gels at various temperatures. Pyranine (P(y)), dissolved in water was introduced as a probe and fluorescence emission (I(p)) from P(y) was monitored during diffusion. Scattered light intensities, I(sc) from PAAm gel was also monitored to observe structural variations during diffusion process. Increase in I(p) intensity was attributed to P(y) diffusion into PAAm gel. On the other hand decrease in I(sc) intensity was interpreted as the variation of the spatial heterogeneities in the system. Li-Tanaka and Fickian models were used to quantify the swelling and diffusion experiments and diffusion coefficients were produced in both cases. Related activation energies were also calculated from the corresponding physical processes.


Later life care planning conversations for older adults and families.
While most older adults have thought about their future care needs, few have discussed their preferences with family members. We interviewed older persons (24), adult children (24), health professionals (23), and representatives of stakeholder associations (3) to understand their views and experiences on later life care (LLC) planning conversations, in terms of (a) their respective roles, and (b) barriers and facilitators that should be taken into account when having these conversations. Roles described included that of information user (older persons), information seeker (family members), and information provider (health care providers). The study identified practical and emotional considerations relevant to LLC planning conversations. This study found strong support for planning for LLC before the need arises, as well as important potential benefits for older adults, family members, and health professionals. There is interest in, and need for, resources to guide families in LLC planning.


Transposable element derived DNaseI-hypersensitive sites in the human genome.
Transposable elements (TEs) are abundant genomic sequences that have been found to contribute to genome evolution in unexpected ways. Here, we characterize the evolutionary and functional characteristics of TE-derived human genome regulatory sequences uncovered by the high throughput mapping of DNaseI-hypersensitive (HS) sites. Human genome TEs were found to contribute substantially to HS regulatory sequences characterized in CD4+ T cells: 23% of HS sites contain TE-derived sequences. While HS sites are far more evolutionarily conserved than non HS sites in the human genome, consistent with their functional importance, TE-derived HS sites are highly divergent. Nevertheless, TE-derived HS sites were shown to be functionally relevant in terms of driving gene expression in CD4+ T cells. Genes involved in immune response are statistically over-represented among genes with TE-derived HS sites. A number of genes with both TE-derived HS sites and immune tissue related expression patterns were found to encode proteins involved in immune response such as T cell specific receptor antigens and secreted cytokines as well as proteins with clinical relevance to HIV and cancer. Genes with TE-derived HS sites have higher average levels of sequence and expression divergence between human and mouse orthologs compared to genes with non TE-derived HS sites. The results reported here support the notion that TEs provide a specific genome-wide mechanism for generating functionally relevant gene regulatory divergence between evolutionary lineages. This article was reviewed by Wolfgang J. Miller (nominated by Jerzy Jurka), Itai Yanai and Mikhail S.Gelfand.


Long-term depression and suicidal ideation outcomes subsequent to emancipation from foster care: pathways to psychiatric risk in the Métis population.
Major depressive episode (MDE) and suicidal ideation (SI) associated with history of foster care placement (HxFCP), and mediating effects of psychosocial and socioeconomic factors through which placement may confer psychiatric risks in the years subsequent to emancipation were examined in a national sample of 7534 Métis. More than one third of emancipated respondents reported past year MDE, a prevalence rate nearly 50% higher than the rate of MDE among Métis respondents without a history of placement in foster care. The 25% lifetime prevalence rate of SI in the emancipated group was more than twice the rate observed in the non-fostered group. Direct effects of HxFCP on post placement MDE and SI were significant in multivariate logistic regression analyses, even when effects of childhood predispositional risk factors were controlled statistically. Emancipated individuals were unduly affected by psychosocial and socioeconomic disadvantages signifying pathways that linked foster care placement history and psychiatric status. Main mediators of the effects demonstrated using effect decomposition procedures were self-esteem, income, and community adversity. The findings warrant consideration of foster care history in clarifying the complex etiologies of suicidal ideation and major depressive episode in the Métis population and risk factors ensuing in the intervening years as integral to the process linking placement to long-term psychiatric outcomes.


Effects of bitter receptor antagonists on behavioral lick responses of mice.
Bitter taste receptors TAS2Rs detect noxious compounds in the oral cavity. Recent heterologous expression studies reported that some compounds function as antagonists for human TAS2Rs. For examples, amino acid derivatives such as γ-aminobutyric acid (GABA) and Nα,Nα-bis(carboxymethyl)-L-Lysine (BCML) blocked responses to quinine mediated by human TAS2R4. Probenecid inhibited responses to phenylthiocarbamide mediated by human TAS2R38. In this study, we investigated the effects of these human bitter receptor antagonists on behavioral lick responses of mice to elucidate whether these compounds also function as bitter taste blockers. In short-term (10 s) lick tests, concentration-dependent lick responses to bitter compounds (quinine-HCl, denatonium and phenylthiourea) were not affected by the addition of GABA or BCML. Probenecid reduced aversive lick responses to denatonium and phenylthiourea but not to quinine-HCl. In addition, taste cell responses to phenylthiourea were inhibited by probenecid. These results suggest some bitter antagonists of human TAS2Rs can work for bitter sense of mouse.


Silk particles, microfibres and nanofibres: A comparative study of their functions in 3D printing hydrogel scaffolds.
Silk, with highly crystalline structure and well-documented biocompatibility, is promising to be used as reinforcing material and build functionalized composite scaffolds. In the present study, we developed chitosan/silk composite scaffolds using silk particles, silk microfibres and nanofibres via 3D printing method. The three forms of silk fillers with varied shapes and dimensions were obtained via different processing methods and evaluated of their morphology, crystalline structure and thermal property. All silk fillers showed different degrees of improvement on printability in terms of ink rheology and printing shape fidelity. Different silk fillers led to different scaffold surface morphology and different roughness, while all reduced the contact angle compared to pure chitosan. Similar reinforcements were observed on compressive modulus, while oscillatory gel strength reinforcement was found to be positively correlated to the filler aspect ratio. Addition of silk introduced no cytotoxicity for that all scaffolds supported a steady cell growth using human fibroblasts. Meanwhile different cellular behaviours were observed on different scaffold surfaces, which can possibly intriguer specific application on soft tissue engineering.


[Views of final-year medical students at Damascus University about clinical skills acquired before graduation].
Medical education in Syrian universities is facing many challenges that may affect the quality of the education and the standard of graduates. We therefore conducted a cross-sectional study using a self-administrated questionnaire with 76 items to investigate the perceptions of 290 final-year medical students regarding the confidence of performing some core clinical skills. A total of 271 responded (response rate 93.4%). Student responses differed. While confidence was highest for skills that do not require practice in the clinical skills laboratory, it was low for skills that need training in emergency and intensive care units, or when students were participating in patient care with partial responsibility. Our findings confirm the need for effective clinical laboratory training, student participation in emergency room shifts, and that students to be allowed to take some egree of responsibility.


Pituitary Adenylate Cyclase-Activating Peptide (PACAP), a Novel Secretagogue, Regulates Secreted Morphogens in Newborn Rat Retina.
Pituitary adenylate cyclase-activating peptide (PACAP)1-38 has been reported to be responsible for regulation of a disparate array of developmental processes in the central nervous system, and its antiapoptotic effect has been revealed in numerous models, pointing to its relevance in the etiology of neurodegenerative disorders. However, its function in retinal development remains unclear. Here, we aimed to point out that versatility can be achieved through interaction with other regulators, in which PACAP can act indirectly on the retinal microenvironment. Wistar rats at age postnatal day 1 were injected intravitreally with PACAP or PAC1 receptor antagonist (PACAP6-38, M65) or VPAC1 antagonist (PG97-269) alone or in combination. Retinas were removed at 3, 6, 12, or 24 hours after injection. Changes in mRNA level were assessed using quantitative PCR, whereas changes in protein levels were measured by Western blot. Intravitreal injection of PACAP or PAC1 receptor antagonists or the VPAC1 antagonist showed that PACAP receptors regulate the expression of five key secreted molecules (i.e., Fgf1, Bmp4, Wnt1, Gdf3, and Ihh), wherease other crucial morphogens (i.e., Fgf2, Fgf4, Fgf8, Fgf9, Shh, and Bmp9) were not affected. Pharmacologic dissection revealed that both PAC1 and VPAC1 induced downstream signaling and could cause upregulation of Fgf1, Bmp4, and Wnt1, whereas expression of Gdf3 might be mediated through the VPAC2 receptor. Our data are the first to shed light on PACAP as a secretagogue regulating a sustained production of morphogens, which in turn could enable PACAP to serve as a mitogen for retinal cells, to induce ganglion cell differentiation, and to contribute to RPE development.


The nature of regularity and irregularity: evidence from Hebrew nominal inflection.
Most evidence for the role of regular inflection as a default operation comes from languages that confound the morphological properties of regular and irregular forms with their phonological characteristics. For instance, regular plurals tend to faithfully preserve the base's phonology (e.g., rat-rats), whereas irregular nouns tend to alter it (e.g., mouse-mice). The distinction between regular and irregular inflection may thus be an epiphenomenon of phonological faithfulness. In Hebrew noun inflection, however, morphological regularity and phonological faithfulness can be distinguished: Nouns whose stems change in the plural may take either a regular or an irregular suffix, and nouns whose stems are preserved in the plural may take either a regular or an irregular suffix. We use this dissociation to examine two hallmarks of default inflection: its lack of dependence on analogies from similar regular nouns, and its application to nonroots such as names. We show that these hallmarks of regularity may be found whether or not the plural form preserves the stem faithfully: People apply the regular suffix to novel nouns that do not resemble existing nouns and to names that sound like irregular nouns, regardless of whether the stem is ordinarily preserved in the plural of that family of nouns. Moreover, when they pluralize names (e.g., the Barak-Barakim), they do not apply the stem changes that are found in their homophonous nouns (e.g., barak-brakim "lightning"), replicating an effect found in English and German. These findings show that the distinction between regular and irregular phenomena cannot be reduced to differences in the kinds of phonological changes associated with those phenomena in English. Instead, regularity and irregularity must be distinguished in terms of the kinds of mental computations that effect them: symbolic operations versus memorized idiosyncrasies. A corollary is that complex words are not generally dichotomizable as "regular" or "irregular"; different aspects of a word may be regular or irregular depending on whether they violate the rule for that aspect and hence must be stored in memory.


T cell receptor stimulation impairs IL-7 receptor signaling by inducing expression of the microRNA miR-17 to target Janus kinase 1.
T cell receptor (TCR)-mediated inhibition of interleukin-7 (IL-7) signaling is important for lineage fate determination in the thymus and for T cell survival in the periphery because uninterrupted IL-7 signaling results in T cell death. The initial event in IL-7 signaling is the transactivation of Janus kinases 1 and 3 (Jak1 and Jak3), which are associated with the cytosolic tails of the IL-7 receptor α chain (IL-7Rα) and the γc subunit, the two cell surface proteins that constitute IL-7R. We found that Jak1 is a highly unstable protein with a half-life of only 1.5 hours, so that continuous Jak1 protein synthesis is required to maintain Jak1 protein in sufficient abundance to support IL-7 signaling. However, we also found that Jak1 protein synthesis was acutely reduced by TCR-responsive microRNAs in the miR-17 family, which targeted Jak1 mRNA (messenger RNA) to inhibit its translation. Thus, this study identifies a molecular mechanism by which TCR engagement acutely disrupts IL-7 signaling.


Assessment of Passive Stiffness of Medial and Lateral Heads of Gastrocnemius Muscle, Achilles Tendon, and Plantar Fascia at Different Ankle and Knee Positions Using the MyotonPRO.
BACKGROUND The aim of this study was to assess the passive stiffness of the medial and lateral gastrocnemius (MG and LG), Achilles tendon (AT), and plantar fascia (PF) at different ankle and knee positions. MATERIAL AND METHODS Stiffness was assessed using a portable hand-held device (MyotonPRO). In 30 healthy participants (15 males, 15 females) with the knee fully extended or flexed 90°, stiffness of the MG, LG, AT, and PF was measured at 50° plantar flexion, 0° (neutral position), and 25° dorsiflexion (not for AT) of the ankle joint by passive joint rotation. RESULTS With the knee fully extended, passive dorsiflexion caused significant increase in muscle stiffness (P<0.001), whereas AT and PF stiffness increased with passive ankle dorsiflexion regardless of knee position (P<0.001). Increased stiffness was observed in MG compared to LG (P<0.001) and at the 3-cm site of AT compared to the 6-cm site (P<0.05). Stiffness was greater in LG compared to MG at -50° plantar flexion (P<0.001) and was greater in MG compared to LG at 25° dorsiflexion (P<0.05). Stiffness of AT increased in a distal-to-proximal pattern: 0 cm >3 cm >6 cm (P<0.001). CONCLUSIONS Stiffness assessed by use of the MyotonPRO was similar assessments using other techniques, suggesting that the MyotonPRO is capable of detecting the variations in stiffness of MG, LG, AT, and PF at different ankle and knee positions.


Functional and evolutionary inference in gene networks: does topology matter?
The relationship between the topology of a biological network and its functional or evolutionary properties has attracted much recent interest. It has been suggested that most, if not all, biological networks are 'scale free.' That is, their connections follow power-law distributions, such that there are very few nodes with very many connections and vice versa. The number of target genes of known transcriptional regulators in the yeast, Saccharomyces cerevisiae, appears to follow such a distribution, as do other networks, such as the yeast network of protein-protein interactions. These findings have inspired attempts to draw biological inferences from general properties associated with scale-free network topology. One often cited general property is that, when compromised, highly connected nodes will tend to have a larger effect on network function than sparsely connected nodes. For example, more highly connected proteins are more likely to be lethal when knocked out. However, the correlation between lethality and connectivity is relatively weak, and some highly connected proteins can be removed without noticeable phenotypic effect. Similarly, network topology only weakly predicts the response of gene expression to environmental perturbations. Evolutionary simulations of gene-regulatory networks, presented here, suggest that such weak or non-existent correlations are to be expected, and are likely not due to inadequacy of experimental data. We argue that 'top-down' inferences of biological properties based on simple measures of network topology are of limited utility, and we present simulation results suggesting that much more detailed information about a gene's location in a regulatory network, as well as dynamic gene-expression data, are needed to make more meaningful functional and evolutionary predictions. Specifically, we find in our simulations that: (1) the relationship between a gene's connectivity and its fitness effect upon knockout depends on its equilibrium expression level; (2) correlation between connectivity and genetic variation is virtually non-existent, yet upon independent evolution of networks with identical topologies, some nodes exhibit consistently low or high polymorphism; and (3) certain genes show low polymorphism yet high divergence among independent evolutionary runs. This latter pattern is generally taken as a signature of positive selection, but in our simulations its cause is often neutral coevolution of regulatory inputs to the same gene.


Notes on Computational Uncertainties in Probabilistic Risk/Safety Assessment.
In this article, we study computational uncertainties in probabilistic risk/safety assessment resulting from the computational complexity of calculations of risk indicators. We argue that the risk analyst faces the fundamental epistemic and aleatory uncertainties of risk assessment with a bounded calculation capacity, and that this bounded capacity over-determines both the design of models and the decisions that can be made from models. We sketch a taxonomy of modelling technologies and recall the main computational complexity results. Then, based on a review of state of the art assessment algorithms for fault trees and event trees, we make some methodological proposals aiming at drawing conceptual and practical consequences of bounded calculability.