[Venoms and medical research].
Animal venoms are complex chemical cocktails, comprising a wide range of biologically active reticulated peptides that target with high selectivity and efficacy a variety of enzymes, membrane receptors, ion channels...Venoms can therefore be seen as large natural libraries of biologically active molecules that are continuously selected and highly refined by the evolution process, up to the point where every molecule is endowed with pharmacological properties that are highly valuable in the context of human use and drug development. Therefore, venom exploration constitutes a prerequisite to drug discovery. However, mass spectrometry and transcriptomics via NGS (Next Generation Sequencing) studies have shown the presence of up to 1000 peptides in the venom of single species of cone snails and spiders. Therefore the global animal venom resource can be seen as a collection of more than 50 to 100 000 000 peptides and proteins of which only ~5000 are known. That extraordinary "Eldorado" of bio-optimized compounds justifies the development of more global and cutting-edge strategies and technologies to explore this resource more efficiently than actually. De novo developed approaches and recently obtained results will be described.


Rational design of a room temperature molecular spin switch. The light-driven coordination induced spin state switch (LD-CISSS) approach.
Extensive use of quantum chemical calculations has been made to rationally design a molecule whose spin state can be switched reversibly using light of two different wavelengths at room temperature in solution. Spin change is induced by changing the coordination number of a nickel complex. The coordination number in turn is switched using a photochromic ligand that binds in one configuration and dissociates in the other. We demonstrate that successful design relies on a precise geometry fit and delicate electronic tuning. Our designer complex exhibits an extremely high long-term switching stability (more than 20 000 cycles) and a high switching efficiency. The high-spin state is extraordinarily stable with a half-life of 400 days at room temperature. Switching between the dia- and paramagnetic state is achieved with visible light (500 and 430 nm). The compound can also be used as a molecular logic gate with light and pH as input and the magnetic state as non-destructive read-out.


Presence of a Haloarchaeal Halorhodopsin-Like Cl- Pump in Marine Bacteria.
Light-driven ion-pumping rhodopsins are widely distributed among bacteria, archaea, and eukaryotes in the euphotic zone of the aquatic environment. H+-pumping rhodopsin (proteorhodopsin: PR), Na+-pumping rhodopsin (NaR), and Cl--pumping rhodopsin (ClR) have been found in marine bacteria, which suggests that these genes evolved independently in the ocean. Putative microbial rhodopsin genes were identified in the genome sequences of marine Cytophagia. In the present study, one of these genes was heterologously expressed in Escherichia coli cells and the rhodopsin protein named Rubricoccus marinus halorhodopsin (RmHR) was identified as a light-driven inward Cl- pump. Spectroscopic assays showed that the estimated dissociation constant (Kd,int.) of this rhodopsin was similar to that of haloarchaeal halorhodopsin (HR), while the Cl--transporting photoreaction mechanism of this rhodopsin was similar to that of HR, but different to that of the already-known marine bacterial ClR. This amino acid sequence similarity also suggested that this rhodopsin is similar to haloarchaeal HR and cyanobacterial HRs (e.g., SyHR and MrHR). Additionally, a phylogenetic analysis revealed that retinal biosynthesis pathway genes (blh and crtY) belong to a phylogenetic lineage of haloarchaea, indicating that these marine Cytophagia acquired rhodopsin-related genes from haloarchaea by lateral gene transfer. Based on these results, we concluded that inward Cl--pumping rhodopsin is present in genera of the class Cytophagia and may have the same evolutionary origins as haloarchaeal HR.


Anti-theory in action? Planning for pandemics, triage and ICU or: how not to bite a bullet.
Anti-theory is a multi-faceted critique of moral theory which, it appears, is undergoing something of reassessment. In a recent paper Hämäläinen discusses the relevance of an anti-theoretical perspective for the activity of applied ethics. This paper explores her view of anti-theory. In particular I examine its relevance for understanding the formal guidance on pandemic flu planning issues by the Department of Health (DoH) in the UK and some subsequent discussions around triage and reverse triage decisions which may be considered by both Primary and Secondary Care Trusts (PCTs and SCTs) (On the division between Primary and Secondary Care Trusts in the UK National Health Service see: http://www.nhs.uk/NHSEngland/thenhs/about/Pages/nhsstructure.aspx [Accessed August 2010]). in setting their own policies and which may face clinicians in the eventuality of a pandemic. Following Hämäläinen in contrasting reflective equilibrium with her anti-theory inspired suggestion of an instrumental approach to moral theory in practice I demonstrate how this understanding complements the diversity of our intuitive moral judgements. Consequentially I suggest that this anti-theoretical instrumental approach is in greater accord with the conditions under which such policy planning and decision making is, or will be, made. Furthermore, on the grounds of keeping open the ethical dimensions of medical practice in conditions of uncertainty, i.e. during a pandemic, I suggest that the anti-theoretical instrumental perspective is, ethically, the preferable approach to producing such policies and guidelines.


Ecological trap for desert lizards caused by anthropogenic changes in habitat structure that favor predator activity.
Anthropogenic habitat perturbation is a major cause of population decline. A standard practice managers use to protect populations is to leave portions of natural habitat intact. We describe a case study in which, despite the use of this practice, the critically endangered lizard Acanthodactylus beershebensis was locally extirpated from both manipulated and natural patches within a mosaic landscape of an afforestation project. We hypothesized that increased structural complexity in planted patches favors avian predator activity and makes these patches less suitable for lizards due to a heightened risk of predation. Spatial rarity of natural perches (e.g., trees) in arid scrublands may hinder the ability of desert lizards to associate perches with low-quality habitat, turning planted patches into ecological traps for such species. We erected artificial trees in a structurally simple arid habitat (similar to the way trees were planted in the afforestation project) and compared lizard population dynamics in plots with these structures and without. Survival of lizards in the plots with artificial trees was lower than survival in plots without artificial trees. Hatchlings dispersed into plots with artificial trees in a manner that indicated they perceived the quality of these plots as similar to the surrounding, unmanipulated landscape. Our results showed that local anthropogenic changes in habitat structure that seem relatively harmless may have a considerable negative effect beyond the immediate area of the perturbation because the disturbed habitat may become an ecological trap.


Chemokine-Releasing Nanoparticles for Manipulation of Lymph Node Microenvironment.
Chemokines (CKs) secreted by the host cells into surrounding tissue establish concentration gradients directing the migration of leukocytes. We propose an in vivo CK gradient remodeling approach based on sustained release of CKs by the crosslinked poly(N-isopropylacrylamide) hydrogel open meshwork nano-particles (NPs) containing internal crosslinked dye affinity baits for a reversible CK binding and release. The sustained release is based on a new principle of affinity off-rate tuning. The NPs with Cibacron Blue F3G-A and Reactive Blue-4 baits demonstrated a low-micromolar affinity binding to IL-8, MIP-2, and MCP-1 with a half-life of several hours at 37°C. The capacity of NPs loaded with IL-8 and MIP-1α to increase neutrophil recruitment to lymph nodes (LNs) was tested in mice after footpad injection. Fluorescently-labeled NPs used as tracers indicated the delivery into the sub-capsular compartment of draining LNs. The animals administered the CK-loaded NPs demonstrated a widening of the sub-capsular space and a strong lymph node influx of leukocytes, while mice injected with control NPs without CKs or bolus doses of soluble CKs alone showed only a marginal neutrophil response. This technology provides a new means therapeutically direct or restore immune cell traffic, and can also be employed for simultaneous therapy delivery.


Three-dimensional textural features of conventional MRI improve diagnostic classification of childhood brain tumours.
The aim of this study was to assess the efficacy of three-dimensional texture analysis (3D TA) of conventional MR images for the classification of childhood brain tumours in a quantitative manner. The dataset comprised pre-contrast T1 - and T2-weighted MRI series obtained from 48 children diagnosed with brain tumours (medulloblastoma, pilocytic astrocytoma and ependymoma). 3D and 2D TA were carried out on the images using first-, second- and higher order statistical methods. Six supervised classification algorithms were trained with the most influential 3D and 2D textural features, and their performances in the classification of tumour types, using the two feature sets, were compared. Model validation was carried out using the leave-one-out cross-validation (LOOCV) approach, as well as stratified 10-fold cross-validation, in order to provide additional reassurance. McNemar's test was used to test the statistical significance of any improvements demonstrated by 3D-trained classifiers. Supervised learning models trained with 3D textural features showed improved classification performances to those trained with conventional 2D features. For instance, a neural network classifier showed 12% improvement in area under the receiver operator characteristics curve (AUC) and 19% in overall classification accuracy. These improvements were statistically significant for four of the tested classifiers, as per McNemar's tests. This study shows that 3D textural features extracted from conventional T1 - and T2-weighted images can improve the diagnostic classification of childhood brain tumours. Long-term benefits of accurate, yet non-invasive, diagnostic aids include a reduction in surgical procedures, improvement in surgical and therapy planning, and support of discussions with patients' families. It remains necessary, however, to extend the analysis to a multicentre cohort in order to assess the scalability of the techniques used.


Medical Devices: Definition, Classification, and Regulatory Implications.
We propose the following definition of a medical device: "A contrivance designed and manufactured for use in healthcare, and not solely medicinal or nutritional." Current regulatory classifications of medical devices are complex and designed primarily for regulators. We propose a simpler classification, based on (1) the site of application of the device, (2) the time scale of its use, and (3) whether it has an external power source. The regulation of medical devices is less well developed than the regulation of medicinal products, which it could follow more closely. In particular, devices that incorporate medicines should be required to meet the same regulatory standards as medicinal products. This would remove the anomaly that some delivery systems that incorporate medicines are classified as devices while other similar systems that deliver the same medicines are classified as medicinal products. Some improvements might also result from more widespread use of registries, such as those used for prosthetic joint replacements. Registries would allow both a prospective examination of the performance of high-risk devices and a retrospective analysis when signals from other sources of information suggest problems. Those who apply for a marketing authorization for a new device should have to assure regulators of its quality of manufacture, safety, and efficacy before licensing. Even the most straightforward device should be shown to be useable in practice. Trials on patients, or at least simulations of use in the real world, should be practicable for most devices.


Role of helix P of the human cytomegalovirus DNA polymerase in resistance and hypersusceptibility to the antiviral drug foscarnet.
Mutations in the human cytomegalovirus DNA polymerase (UL54) can not only decrease but also increase susceptibility to the pyrophosphate (PP(i)) analogue foscarnet. The proximity of L802M, which confers resistance, and K805Q, which confers hypersusceptibility, suggests a possible unifying mechanism that affects drug susceptibility in one direction or the other. We found that the polymerase activities of L802M- and K805Q-containing mutant enzymes were literally indistinguishable from that of wild-type UL54; however, susceptibility to foscarnet was decreased or increased, respectively. A comparison with the crystal structure model of the related RB69 polymerase suggests that L802 and K805 are located in the conserved alpha-helix P that is implicated in nucleotide binding. Although L802 and K805 do not appear to make direct contacts with the incoming nucleotide, it is conceivable that changes at these residues could exert their effects through the adjacent, highly conserved amino acids Q807 and/or K811. Our data show that a K811A substitution in UL54 causes reductions in rates of nucleotide incorporation. The activity of the Q807A mutant is only marginally affected, while this enzyme shows relatively high levels of resistance to foscarnet. Based on these data, we suggest that L802M exerts its effects through subtle structural changes in alpha-helix P that affect the precise positioning of Q807 and, in turn, its presumptive involvement in binding of foscarnet. In contrast, the removal of a positive charge associated with the K805Q change may facilitate access or increase affinity to the adjacent Q807.


Does postoperative drain amylase predict pancreatic fistula after pancreatectomy?
Previous studies suggest that after pancreatectomy, drain fluid amylase obtained on postoperative day 1 (DFA1) >5,000 U/L correlates with the development of postoperative pancreatic fistula (PF).(1,2) We sought to validate whether DFA1 is a clinically useful predictor of PF and to evaluate whether DFA1 correlates with PF severity. Using a prospective database, we reviewed records from patients having pancreatectomy between 2010 and 2012. Presence and grade of PF were determined using the consensus guidelines from the International Study Group on Pancreatic Fistula (ISGPF).(1) RESULTS: Sixty-three patients who underwent pancreatectomy had a documented DFA1. There were 27 (43%) who developed PF: 2 (7%) were grade A, 18 grade B (67%), and 7 were grade C (26%). Median DFA1 in patients with PF (4,600 U/L, range 32 to 16,900 U/L) was significantly higher than in those without PF (45 U/L, range 2 to 5,840 U/L; p < 0.001). When DFA1 was analyzed at varying cutoff values, correlation of DFA1 with PF was high. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were assessed at varying levels of DFA1. Highest sensitivity (96%) and NPV (96%) were obtained with a cutoff DFA1 of <100 U/L. On multivariate analysis, DFA1 >100 U/L was the only significant predictor of PF when controlling for gland texture, duct size, pathology, and neoadjuvant radiation. There was no statistically significant relationship between DFA1 and PF grade. In patients undergoing pancreatic resection, a cutoff DFA1 of 100 U/L resulted in high sensitivity and NPV. Early drain removal may be safe in these patients. Further studies are recommended to validate the role of DFA1 in excluding PF and assisting in management of surgical drains.


High prevalence and incidence of gonorrhoea and chlamydia in young women eligible for HIV pre-exposure prophylaxis in South Africa and Zimbabwe: results from the HPTN 082 trial.
We investigated the prevalence, incidence and factors associated with sexually transmitted infections (STIs) among young African women seeking HIV pre-exposure prophylaxis (PrEP). HPTN 082 was a prospective, open-label PrEP study enrolling HIV-negative sexually active women aged 16-25 years in Cape Town and Johannesburg, South Africa, and Harare, Zimbabwe. Endocervical swabs from enrolment, months 6 and 12 were tested for Neisseria gonorrhoeae (GC) and Chlamydia trachomatis (CT) by nucleic acid amplification, and Trichomonas vaginalis (TV) by a rapid test. Intracellular tenofovir-diphosphate (TFV-DP) concentrations in dried blood spots were measured at months 6 and 12. Associations between risk characteristics and STI outcomes were assessed using Poisson regression. Of 451 enrolled participants, 55% had an STI detected at least once. CT incidence was 27.8 per 100 person-years (py) (95% CI 23.1, 33.2), GC incidence was 11.4 per 100 py (95% CI 8.5, 15.0) and TV incidence was 6.7 per 100 py (95% CI 4.5, 9.5). 66% of incident infections were diagnosed in women uninfected at baseline. Baseline cervical infection (GC or CT) risk was highest in Cape Town (relative risk (RR) 2.38, 95% CI 1.35, 4.19) and in those not living with family (RR 1.87, 95% 1.13, 3.08); condom use was protective (RR 0.67, 95% CI 0.45, 0.99). Incident CT was associated with baseline CT (RR 2.01; 95% CI 1.28, 3.15) and increasing depression score (RR 1.05; 95% CI 1.01, 1.09). Incident GC was higher in Cape Town (RR 2.40; 95% CI 1.18, 4.90) and in participants with high PrEP adherence (TFV-DP concentrations ≥700 fmol/punch) (RR 2.04 95% CI 1.02, 4.08). Adolescent girls and young women seeking PrEP have a high prevalence and incidence of curable STIs. Alternatives to syndromic management for diagnosis and treatment are needed to reduce the burden of STIs in this population. NCT02732730.


A software tool for removing patient identifying information from clinical documents.
We created a software tool that accurately removes all patient identifying information from various kinds of clinical data documents, including laboratory and narrative reports. We created the Medical De-identification System (MeDS), a software tool that de-identifies clinical documents, and performed 2 evaluations. Our first evaluation used 2,400 Health Level Seven (HL7) messages from 10 different HL7 message producers. After modifying the software based on the results of this first evaluation, we performed a second evaluation using 7,190 pathology report HL7 messages. We compared the results of MeDS de-identification process to a gold standard of human review to find identifying strings. For both evaluations, we calculated the number of successful scrubs, missed identifiers, and over-scrubs committed by MeDS and evaluated the readability and interpretability of the scrubbed messages. We categorized all missed identifiers into 3 groups: (1) complete HIPAA-specified identifiers, (2) HIPAA-specified identifier fragments, (3) non-HIPAA-specified identifiers (such as provider names and addresses). In the results of the first-pass evaluation, MeDS scrubbed 11,273 (99.06%) of the 11,380 HIPAA-specified identifiers and 38,095 (98.26%) of the 38,768 non-HIPAA-specified identifiers. In our second evaluation (status postmodification to the software), MeDS scrubbed 79,993 (99.47%) of the 80,418 HIPAA-specified identifiers and 12,689 (96.93%) of the 13,091 non-HIPAA-specified identifiers. Approximately 95% of scrubbed messages were both readable and interpretable. We conclude that MeDS successfully de-identified a wide range of medical documents from numerous sources and creates scrubbed reports that retain their interpretability, thereby maintaining their usefulness for research.


Public-private partnerships for equity of access to care for tuberculosis and HIV/AIDS: lessons from Pune, India.
The private medical sector is an important and rapidly growing source of health care in India. Private medical providers (PMP) are a diverse group, known to be poorly regulated by government policies and variable in the quality of services provided. Studies of their practices have documented inappropriate prescribing as well as violation of ethical guidelines on patient care. However, despite the critique that inequitable services characterise the private medical sector, PMPs remain important and preferred providers of primary care. This paper argues that their greater involvement in the public health framework is imperative to addressing the goal of health equity. Through a review of two research studies conducted in Pune, India, to examine the role of PMPs in tuberculosis (TB) and HIV/AIDS care, the themes of equity and access arising in private sector delivery of care for TB and HIV/AIDS are explored and the future policy directions for involving PMPs in public health programmes are highlighted. The paper concludes that public-private partnerships can enhance continuity of care for patients with TB and HIV/AIDS and argues that interventions to involve PMPs must be supported by appropriate research, along with political commitment and leadership from both public and private sectors.


Vascular access placement and mortality in elderly incident hemodialysis patients.
Arteriovenous fistulas (AVFs) are the preferred vascular access type in most hemodialysis patients. However, the optimal vascular access type in octogenarians and older (≥80 years) hemodialysis patients remains widely debated given their limited life expectancy and lower AVF maturation rates. Among incident hemodialysis patients receiving care in a large national dialysis organization during 2007-2011, we examined patterns of vascular access type conversion in 1 year following dialysis initiation in patients <80 versus ≥80 years of age. Among a subcohort of patients ≥80 years of age, we examined the association between vascular access type conversion and mortality using multivariable survival models. In the overall cohort of 100 804 patients, the prevalence of AVF/arteriovenous graft (AVG) as the primary vascular access type increased during the first year of hemodialysis, but plateaued thereafter. Among 8356 patients ≥80 years of age and treated for >1 year, those with initial AVF/AVG use and placement of AVF from a central venous catheter (CVC) had lower mortality compared with patients with persistent CVC use. When the reference group was changed to patients who had AVF placement from a CVC in the first year of dialysis, those with initial AVF use had similar mortality. A longer duration of CVC use was associated with incrementally worse survival. Among incident hemodialysis patients ≥80 years of age, placement of an AVF from a CVC within the first year of dialysis had similar mortality compared with initial AVF use. Our data suggest that initial CVC use with later placement of an AVF may be an acceptable option among elderly hemodialysis patients.


Dosage escalation of intravesical oxybutynin in the treatment of neurogenic bladder patients.
We prospectively analyzed the dose dependent outcome and side effects of neurogenic bladder patients with intravesical application of oxybutynin at our centre. We examined the data of 32 patients with neurogenic bladders and detrusor hyperreflexia. We registered clinical outcome, continence situation, side effects and urodynamic data of patients with (A) standard dosages of intravesical oxybutynin (0.3 mg/kg bodyweight per day) and (B) with increasing dosages in steps of 0.2 mg/kg bodyweight per day up to 0.9 mg/kg bodyweight per day. We examined 32 patients aged 1 to 34 years, mean age 12 years. 21/32 patients became totally continent with the dosage (A). They showed a significant (P<0.01) decrease in the median max detrusor pressure (MDP) and a significant (P<0.01) increase in the median compliance and the median age adjusted bladder capacity (AABC). Eleven out of 32 patients remained incontinent under this dosage (A). Their median MDP, their median compliance and their median AABC remained nearly unchanged. Seven out of 11 incontinent patients under dosage (A) were treated efficiently with the higher dosages (B). Their median necessary dosage escalation to achieve treatment success was 0.7 mg/kg bodyweight per day (range 0.5 to 0.9 mg/kg bodyweight per day). Their median MDP was significantly (P<0.05) decreased and their median compliance and median AABC were significantly (P<0.05) increased. Four out of 11 patients remained incontinent and showed only little improvement in urodynamic data. Two out of 11 patients with the dosage escalation (B) showed side effects at a dosage of 0. 9 mg/kg bodyweight per day. The intravesical application of oxybutynin was a well tolerated and efficacious therapy. The topical oxybutynin therapy dosage (A) was efficient in 66% of our selected patients, the escalating dosage titration (B) could increase the efficiency to 87%.


Distinct functions of Period2 and Period3 in the mouse circadian system revealed by in vitro analysis.
The mammalian circadian system, which is composed of a master pacemaker in the suprachiasmatic nuclei (SCN) as well as other oscillators in the brain and peripheral tissues, controls daily rhythms of behavior and physiology. Lesions of the SCN abolish circadian rhythms of locomotor activity and transplants of fetal SCN tissue restore rhythmic behavior with the periodicity of the donor's genotype, suggesting that the SCN determines the period of the circadian behavioral rhythm. According to the model of timekeeping in the SCN, the Period (Per) genes are important elements of the transcriptional/translational feedback loops that generate the endogenous circadian rhythm. Previous studies have investigated the functions of the Per genes by examining locomotor activity in mice lacking functional PERIOD proteins. Variable behavioral phenotypes were observed depending on the line and genetic background of the mice. In the current study we assessed both wheel-running activity and Per1-promoter-driven luciferase expression (Per1-luc) in cultured SCN, pituitary, and lung explants from Per2(-/-) and Per3(-/-) mice congenic with the C57BL/6J strain. We found that the Per2(-/-) phenotype is enhanced in vitro compared to in vivo, such that the period of Per1-luc expression in Per2(-/-) SCN explants is 1.5 hours shorter than in Per2+/+ SCN, while the free-running period of wheel-running activity is only 11 minutes shorter in Per2(-/-) compared to Per2+/+ mice. In contrast, circadian rhythms in SCN explants from Per3(-/-) mice do not differ from Per3+/+ mice. Instead, the period and phase of Per1-luc expression are significantly altered in Per3(-/-) pituitary and lung explants compared to Per3+/+ mice. Taken together these data suggest that the function of each Per gene may differ between tissues. Per2 appears to be important for period determination in the SCN, while Per3 participates in timekeeping in the pituitary and lung.


A new cytochrome subunit bound to the photosynthetic reaction center in the purple bacterium, Rhodovulum sulfidophilum.
The nucleotide sequence of the puf operon, which contains the genes encoding the B870 light-harvesting protein and the reaction center complex of the purple photosynthetic bacterium, Rhodovulum sulfidophilum, was determined. The operon, which consisted of six genes, pufQ, pufB, pufA, pufL, pufM, and pufC, is a new variety in photosynthetic bacteria in the sense that pufQ and pufC coexist. The amino acid sequence of the cytochrome subunit of the reaction center deduced from the pufC sequence revealed that this cytochrome contains only three possible heme-binding motifs; the heme-1-binding motif of the corresponding tetraheme cytochrome subunits was not present. This is the first exception of the "tetraheme" cytochrome family in purple bacteria and green filamentous bacteria. The pufC sequence also revealed that the sixth axial ligands to heme-1 and heme-2 irons were not present in the cytochrome either. This cytochrome was actually detected in membrane preparation as a 43-kDa protein and shown to associate functionally with the photosynthetic reaction center as the immediate electron donor to the photo-oxidized special pair of bacteriochlorophyll. This new cytochrome should be useful for studies on the role of each heme in the cytochrome subunit of the bacterial reaction center and the evolution of proteins in photosynthetic electron transfer systems.


Fast multidimensional NMR spectroscopy for sparse spectra.
Multidimensional NMR spectroscopy is widely used for studies of molecular and biomolecular structure. A major disadvantage of multidimensional NMR is the long acquisition time which, regardless of sensitivity considerations, may be needed to obtain the final multidimensional frequency domain coefficients. In this article, a method for under-sampling multidimensional NMR acquisition of sparse spectra is presented. The approach is presented in the case of two-dimensional NMR acquisitions. It relies on prior knowledge about the support in the two-dimensional frequency domain to recover an over-determined system from the under-determined system induced in the linear acquisition model when under-sampled acquisitions are performed. This over-determined system can then be solved with linear least squares. The prior knowledge is obtained efficiently at a low cost from the one-dimensional NMR acquisition, which is generally acquired as a first step in multidimensional NMR. If this one-dimensional acquisition is intrinsically sparse, it is possible to reconstruct the corresponding two-dimensional acquisition from far fewer observations than those imposed by the Nyquist criterion, and subsequently to reduce the acquisition time. Further improvements are obtained by optimizing the sampling procedure for the least-squares reconstruction using the sequential backward selection algorithm. Theoretical and experimental results are given in the case of a traditional acquisition scheme, which demonstrate reliable and fast reconstructions with acceleration factors in the range 3-6. The proposed method outperforms the CS methods (OMP, L1) in terms of the reconstruction performance, implementation and computation time. The approach can be easily extended to higher dimensions and spectroscopic imaging.


Weight gain at the time of menopause.
We studied prospectively the weight change and the effect of weight change on changes in coronary heart disease risk factors in a population-based sample of 485 middle-aged women. All women were studied first in 1983 to 1984, when they were premenopausal and aged 42 to 50 years, and then restudied in 1987. Women gained an average of 2.25 +/- 4.19 kg during this 3-year period; 20% of women gained 4.5 kg or more, and only 3% lost 4.5 kg or more. There were no significant differences in weight gain of women who remained premenopausal and those who had a natural menopause (+2.07 kg vs +1.35 kg). Weight gain was significantly associated with increases in blood pressure and levels of total cholesterol, low-density lipoprotein cholesterol, triglycerides, and fasting insulin. Weight gain is thus a common occurrence for women at the time of menopause and is related to the changes in coronary heart disease risk factors observed during this period. Efforts to lose weight or to prevent weight gain may help to mitigate the worsening in coronary heart disease risk factors in middle-aged women.


A meta-analysis of self-reported achievement goals and nonself-report performance across three achievement domains (work, sports, and education).
During the past three decades, the achievement goal approach to achievement motivation has emerged as an influential area of research, and is dedicated to understanding the reasons behind the individual's drive to achieve competence and performance. However, the current literature on achievement goals is segmented rather than integrated. That is, citations across the three major and distinct achievement domains (work, education, and sports) are more the exception than the rule and similarities and differences between findings for the different achievement domains have yet to be tested. The purpose of the present study was to examine the relationships between self-reported achievement goals and nonself-report performance through meta-analysis, and the moderating potential of achievement domain. Identifying achievement domain as moderator improves our understanding to which contexts we can (not) generalize conclusions to, it helps to understand seemingly inconsistent findings, and opens avenues for future research on the underlying processes. Because the achievement goal (AG) measure used in a study is partially confounded with achievement domain, we examined the moderating role of this variable as well. Our findings suggest that - overall - approach goals (either mastery or performance) were associated positively with performance attainment, whereas avoidance goals (either mastery or performance) were associated negatively with performance attainment. These relationships were moderated by achievement domain. For example, relative to the education or work domain, in the sports domain, we did not observe negative correlations between avoidance goals and performance. The absence of statistical moderation due to AG measure suggests that the observed moderation of achievement domain cannot be explained by the AG measure utilized. We suggest further steps to integrate the achievement goal literature, and accordingly, to broaden and deepen understanding of performance attainment in competence-relevant settings, including the workplace, the sports field, and the classroom.


Changes in topoisomerase I levels and localization during myeloid maturation in vitro and in vivo.
Changes in topoisomerase I (topo I) levels and localization were examined during the course of granulocytic maturation in vitro and in vivo. Western blotting revealed that granulocytic maturation in DMSO-treated HL-60 human leukemia cells was accompanied by a 5-fold decrease in topo I polypeptide content. Consistent with this result, 3- to 5-fold higher concentrations of the topo I poison camptothecin were required to stabilize topo I-DNA adducts in DMSO-treated HL-60 cells compared to untreated cells. Northern blotting revealed that these changes occurred without any decrease in topo I message. Immunolocalization studies revealed that these quantitative changes were accompanied by redistribution of topo I away from the nucleoli, where it was prominently accumulated in untreated HL-60 cells, to a more uniform nuclear distribution in DMSO-treated cells. Similar changes occurred during granulocytic maturation in human marrow in vivo. Western blotting revealed that topo I levels in normal progranulocytes were 50% as high as those in HL-60 cells, levels in metamyelocytes were 35% as high as HL-60 cells, and levels in peripheral blood granulocytes were 5% as high as HL-60 cells. Two other polypeptides that are concentrated in nucleoli, poly(ADP-ribose) polymerase and B23/nucleophosmin, also decreased during the course of granulocytic maturation. These changes were accompanied by an alteration in topo I localization similar to that observed in HL-60 cells during the course of granulocytic maturation. Conversely, treatment of human lymphocytes with the mitogenic lectin concanavalin A resulted in a 3-fold increase in topo I polypeptide content concomitant with a prominent increase in the amount of nucleolar antigen. These observations not only provide a context for understanding the recent observation that topo I levels are higher in human leukemia specimens than in normal marrow but also raise the possibility that elevated topo I levels in other cells might reflect alterations in nucleolar structure and function.


Anterior maxillary wall and lacrimal duct relationship - CT analysis for prelacrimal access to the maxillary sinus.
The distance between the anterior wall of the maxillary sinus and the nasolacrimal duct shows a large individual variation. To evaluate the feasibility of accessing the maxillary sinus through a prelacrimal window access (PLWA), a series of 100 paranasal CT scans from adult patients was analysed retrospectively. The distance between the anterior maxillary wall and the anterior border of the lacrimal duct (= prelacrimal window) were measured in 200 sides. A distance of more the 7 mm was found in 12.5% maxillary sinuses and would enable straight forward PLWA. A distance between smaller than 7mm and larger than 3mm was present in 56.5% of sinuses, and would make surgical access more demanding. In 31.5% of maxillary sinuses the distance was smaller than or equal to 3mm and in these patients this approach would be difficult without transecting the nasolacrimal duct. Only in 12.5% of sinuses a prelacrimal endoscopic access is readily feasible, while in 56.5% temporary tear sac dislocation is required and in 31.5% lacrimal sac dislocation is always needed along with a significant amount of bone removal to enable PLWA.


2-Arylaminobenzothiazole-arylpropenone conjugates as tubulin polymerization inhibitors.
A new series of 2-arylaminobenzothiazole-arylpropenone conjugates 5-6(a-r) was designed, synthesized and investigated for their cytotoxic potency against the various human cancer cell lines. Most of these conjugates exhibited cytotoxic activity and inhibited in vitro tubulin polymerization effectively. Conjugates 5d and 6d cause cell cycle blocks in the G2/M phase in HeLa cells and treatments with 5d and 6d manifested increased mRNA and protein levels of the G2/M marker, cyclin B1. Immunocytochemistry revealed loss of intact microtubule structure in cells treated with 5d and 6d. Western blot analysis revealed that these conjugates accumulate more tubulin in the soluble fraction. Moreover, the triggering of apoptotic cell death after mitotic arrest was investigated by studying their effect on Hoechst staining, mitochondrial membrane potential, ROS generation.


Engraftment potential of human fetal hematopoietic cells in NOD/SCID mice is not restricted to mitotically quiescent cells.
During fetal development, there is a continued demand for large numbers of primitive and mature hematopoietic cells. This demand may require that all potential hematopoietic stem cells (HSCs) migrate effectively to emerging hematopoietic sites and subsequently contribute to blood cell production, regardless of their cell cycle status. We recently established that umbilical cord blood cells in the G(1) phase of the cell cycle have a repopulating potential similar to cells in G(0), suggesting that cycling prenatal and neonatal HSCs may have the same functional capabilities described for quiescent, but not cycling, cells from adult sources. To establish the relationship between cell cycle status and hematopoietic potential at early stages of human ontogeny, the in vivo engraftment potential of mitotically defined fetal liver (FL) and fetal bone marrow (FBM) cells were examined in NOD/SCID recipients. Following transplantation of the same numbers of G(0), G(1), or S/G(2)+M CD34(+) cells from FL, equivalent percentages of recipient mice were chimeric (55%, 60%, and 60%, respectively). FBM-derived CD34(+) cells in all phases of the cell cycle engrafted in conditioned recipients and sustained human hematopoiesis, albeit at lower levels than their FL-derived counterparts. Multilineage differentiation was evident in all transplanted mice independent of the source or cell cycle status of graft cells. In addition, levels of chimerism in mice transplanted with fetal blood-derived G(0) or G(1) CD34(+) lineage-depleted cells were similar. These results support the assertion that mitotically quiescent and cycling fetal hematopoietic cells contain marrow-repopulating stem cells capable of multilineage engraftment in NOD/SCID mouse recipients.


Wound Bed Preparation for Capsulectomy Using a Hydrosurgery System.
Wound bed preparation is necessary for proper wound healing. The case of a 75-year-old man with good outcomes after using a hydrosurgery system for capsulectomy is presented. At a 2-month follow-up visit, a fistula measuring 15 cm x 10 cm was found to have developed in the patient's left scapular region after the first wide-excision surgery for soft tissue sarcoma and reconstruction of the defect using a local flap. The wound had fluid collection and a capsule that was then debrided with a hydrosurgery system. Since no infection was detected, closure with a pedicled latissimus dorsi (LD) muscle flap (15 cm x 6 cm) was performed. Due to persistent fluid collection, the LD harvest site had to be drained after discharge (18 days postoperatively); however, in the regions debrided by the hydrosurgery system, the suction drain could be removed early. In the case reported herein, the hydrosurgery system proved beneficial for capsulectomy.


Patterns of health care utilization for low back pain.
The purpose of this study was to determine if primary care patients with low back pain (LBP) cluster into definable care utilization subgroups that can be explained by patient and provider characteristics. Adult primary care patients with an incident LBP encounter were identified from Geisinger Clinic electronic health records over 5 years. Two-thirds of the cohort had only one to two encounters. Principal component analysis was applied to the data from the remaining one-third on use of ambulatory, inpatient, emergency department, and surgery care and use of magnetic resonance imaging, injections, and opioids in 12 months following the incident encounter. Groups were compared on demographics, health behaviors, chronic and symptomatic disease burden, and a measure of physician efficiency. Six factors with eigenvalues >1.5 explained 71% of the utilization variance. Patient subgroups were defined as: 1-2 LBP encounters; 2+ surgeries; one surgery; specialty care without primary care; 3+ opioid prescriptions; laboratory dominant care; and others. The surgery and 3+ opioid subgroups, while accounting for only 10.4% of the cohort, had used disproportionately more magnetic resonance imaging, emergency department, inpatient, and injectable resources. The specialty care subgroup was characterized by heavy use of inpatient care and the lowest use of injectables. Anxiety disorder and depression were not more prevalent among the surgery patients than in the others. Surgery patients had features in common with specialty care patients, but were older, had higher prevalence of Fibromyalgia, and were associated primary care physicians with worse efficiency scores. LBP care utilization is highly variable and concentrated in small subgroups using disproportionate amounts of potentially avoidable care that reflect both patient and provider characteristics.


BIGH3 gene mutations and rapid detection in Korean patients with corneal dystrophy.
Mutations in the BIGH3 gene on chromosome 5q31 cause four distinct autosomal dominant corneal dystrophies. We sought to determine whether the BIGH3 gene mutation was responsible for corneal dystrophy in Korean patients. Polymerase chain reaction single strand conformational polymorphism (PCR-SSCP) analysis was performed with the DNA from patients and healthy individuals. We sequenced the PCR products with the aberrant SSCP pattern to identify the mutation. Mutant-specific reverse primers were used to screen genomic DNA for the identified mutations. We identified mutations R124C in the CDL1 family and R124H in four families with a granular dystrophy. We identified our granular dystrophy to be Avellino corneal dystrophy (ACD). Eighteen of 20 patients with a granular dystrophy contained the same R124H mutation, indicating that mutation R124H was very common in Korean patients with ACD. During this study, we identified a new polymorphism (T1667C, F540F). This is the first report of mutations found in the BIGH3 gene in Korean families with corneal dystrophy. We report that the majority (90%) of ACD patients in Korea carry the R124H mutation. Mutant-specific reverse primers can be used to screen efficiently for CDL1 and ACD.


A Good Death.
A good death is hard to find. Family members tell us that loved ones die in the wrong place-the hospital-and do not receive high-quality care at the end of life. This issue of the Hastings Center Report offers two articles from authors who strive to provide good end-of-life care and to prevent needless suffering. We agree with their goals, but we have substantial reservations about the approaches they recommend. Respect for the decisions of patients and their surrogates is a relatively new and still vulnerable aspect of medical care. For thousands of years, patients and surrogates had no say in medical decision-making. Today, standards support shared decision-making, but these articles both carve out exceptions to those standards, limiting the rights of patients and families in decisions about specific end-of-life treatments. As bioethics consultants in an acute care setting, we frequently confront conflicts similar to those described by Jeffrey Berger and by Ellen Robinson and colleagues. In such cases, our service emphasizes redoubled efforts at communication and mediation. Focusing on goals and values, rather than interventions, produces the best possible collaboration in health care decision-making. Cases in which we would overturn a surrogate's recommendations regarding palliative sedation or do-not-resuscitate orders are rare and require careful processes and clear evidence that the surrogate's choice is contrary to patient values.


Neuroanatomical Dissections of Unilateral Visual Neglect Symptoms: ALE Meta-Analysis of Lesion-Symptom Mapping.
Unilateral visual neglect is commonly defined as impaired ability to attend to stimuli presented on the side of visual space contralateral to the brain lesion. However, behavioral analyses indicate that different neglect symptoms can dissociate. The neuroanatomy of the syndrome has been hotly debated. Some groups have argued that the syndrome is linked to posterior parietal cortex lesions, while others report damage within regions including the superior temporal gyrus, insula, and basal ganglia. Several recent neuroimaging studies provide evidence that heterogeneity in the behavioral symptoms of neglect can be matched by variations in the brain lesions, and that some of the discrepancies across earlier findings might have resulted from the use of different neuropsychological tests and/or varied measures within the same task for diagnosing neglect. In this paper, we review the evidence for dissociations between both the symptoms and the neural substrates of unilateral visual neglect, drawing on ALE (anatomic likelihood estimation) meta-analyses of lesion-symptom mapping studies. Specifically, we examine dissociations between neglect symptoms associated with impaired control of attention across space (in an egocentric frame of reference) and within objects (in an allocentric frame of reference). Results of ALE meta-analyses indicated that, while egocentric symptoms are associated with damage within perisylvian network (pre- and postcentral, supramarginal, and superior temporal gyri) and damage within sub-cortical structures, more posterior lesions including the angular, middle temporal, and middle occipital gyri are associated with allocentric symptoms. Furthermore, there was high concurrence in deficits associated with white matter lesions within long association (superior longitudinal, inferior fronto-occipital, and inferior longitudinal fasciculi) and projection (corona radiata and thalamic radiation) pathways, supporting a disconnection account of the syndrome. Using this evidence we argue that different forms of neglect link to both distinct and common patterns of gray and white matter lesions. The findings are discussed in terms of functional accounts of neglect and theoretical models based on computational studies of both normal and impaired attention functions.


Mapping Low-Dimensional Dynamics to High-Dimensional Neural Activity: A Derivation of the Ring Model From the Neural Engineering Framework.
Empirical estimates of the dimensionality of neural population activity are often much lower than the population size. Similar phenomena are also observed in trained and designed neural network models. These experimental and computational results suggest that mapping low-dimensional dynamics to high-dimensional neural space is a common feature of cortical computation. Despite the ubiquity of this observation, the constraints arising from such mapping are poorly understood. Here we consider a specific example of mapping low-dimensional dynamics to high-dimensional neural activity-the neural engineering framework. We analytically solve the framework for the classic ring model-a neural network encoding a static or dynamic angular variable. Our results provide a complete characterization of the success and failure modes for this model. Based on similarities between this and other frameworks, we speculate that these results could apply to more general scenarios.


Evaluation of factors that motivate participants to consent for non-therapeutic trials in India.
Several factors that motivate individuals to participate in non-therapeutic studies have been identified. This study was conducted as limited data is available regarding these motivations from developing countries. This was a single-centre study conducted over 4 months in which a questionnaire was administered to 102 healthy participants and 16 patient participants who had earlier taken part in non-therapeutic studies at our centre. Descriptive statistics and univariate analysis were used to analyse data. The most common motivation among healthy participants was financial reward (65%) followed by altruism, free medical check up, curiosity and personal health benefit. Patient participants, however, most commonly said they consented to take part in the trial as they were 'invited to participate by the treating physician' (88%). In comparison with the patient participants, healthy participants were more likely to be satisfied with the financial reward (p=0.02), and recommend participation in studies to friends or relatives (p=0.0013). The most common motivating factor to participate in non-therapeutic studies appears to be different for healthy participants (financial reward) and patient participants (invitation to participate by the physician). Participants also felt that adequate information and care was given to them during the trial, and that they would participate in future clinical studies, and would also recommend such studies to their friends.


WormQTL--public archive and analysis web portal for natural variation data in Caenorhabditis spp.
Here, we present WormQTL (http://www.wormqtl.org), an easily accessible database enabling search, comparative analysis and meta-analysis of all data on variation in Caenorhabditis spp. Over the past decade, Caenorhabditis elegans has become instrumental for molecular quantitative genetics and the systems biology of natural variation. These efforts have resulted in a valuable amount of phenotypic, high-throughput molecular and genotypic data across different developmental worm stages and environments in hundreds of C. elegans strains. WormQTL provides a workbench of analysis tools for genotype-phenotype linkage and association mapping based on but not limited to R/qtl (http://www.rqtl.org). All data can be uploaded and downloaded using simple delimited text or Excel formats and are accessible via a public web user interface for biologists and R statistic and web service interfaces for bioinformaticians, based on open source MOLGENIS and xQTL workbench software. WormQTL welcomes data submissions from other worm researchers.


Phenotype adjustment promotes adaptive evolution in a game without conflict.
Organisms may adjust their phenotypes in response to social and physical environments. Such phenotypic plasticity is known to help or retard adaptive evolution. Here, we study the evolutionary outcomes of adaptive phenotypic plasticity in an evolutionary game involving two players who have no conflicts of interest. A possible example is the growth and sex allocation of a lifelong pair of shrimps entrapped in the body of a sponge. We consider random pair formation, the limitation of total resources for growth, and the needs of male investment to fertilize eggs laid by the partner. We compare the following three different evolutionary dynamics: (1) No adjustment: each individual develops a phenotype specified by its own genotype; (2) One-player adjustment: the phenotype of the first player is specified by its own genotype, and the second player chooses the phenotype that maximizes its own fitness; (3) Two-player adjustment: the first player exhibits an initial phenotype specified by its own genotype, the second player chooses a phenotype given that of the first player, and finally, the first player readjusts its phenotype given that of the second player. We demonstrate that both one-player and two-player adjustments evolve to achieve maximum fitness. In contrast, the dynamics without adjustment fails in some cases to evolve outcomes with the highest fitness. For an intermediate range of male cost, the evolution of no adjustment realizes two hermaphrodites with equal size, whereas the one-player and two-player adjustments realize a small male and a large female.


The cardiovascular and subjective effects of intravenous cocaine and morphine combinations in humans.
Intravenous cocaine (COC) and morphine (MOR) combinations ("speedballs") were administered to nine research volunteers during 12 daily experimental sessions. During each session, a single dose of MOR sulfate (0, 5 and 10 mg/70 kg) was administered i.v. in combination with a single dose of COC hydrochloride (0, 8, 16 and 32 mg/70 kg). All possible COC-MOR combinations were each tested once. Measures of subjective effects were obtained repeatedly, heart rate, diastolic and systolic blood pressure were sampled every 2 min and blood levels of COC and MOR were obtained at three time points. Both COC and MOR alone significantly increased peak heart rate, diastolic pressure and systolic pressure. The cardiovascular effects of COC were larger and longer in duration than morphine, as indicated by larger area under the curve measures compared to MOR. COC alone increased visual analog scales ratings of "stimulated" and A scores of the Addiction Research Center Inventory, whereas MOR alone increased opiate symptoms and ratings of "sedated" and both drugs increased ratings of "high." For the most part, the cardiovascular effects of COC-MOR combinations could be predicted by the effects of COC alone, and the subjective effects of the combinations could be predicted by either drug alone. The drug combination produced increases in cardiovascular and subjective effects that were less than predicted by an effect addition model of drug interaction. The disposition of both COC and MOR was unaffected by the presence of the other drug. These results suggest that the self-administration of this drug combination may be related to a unique profile of opiate and stimulant effects instead of an alteration in the effects produced by either drug alone.


Myelodysplastic syndromes: iron overload consequences and current chelating therapies.
Chronic red blood cell transfusion support in patients with myelodysplastic syndromes (MDS) is often necessary but may cause hemosiderosis and its consequences. The pathophysiologic effects of iron overload relate to increased non-transferrin bound iron generating toxic oxygen free radicals. Studies in patients with MDS and thalassemia major have shown adverse clinical effects of chronic iron overload on cardiac function in patients who underwent polytransfusion. Iron chelation therapy in patients with thalassemia who were effectively chelated has prevented or partially reversed some of these consequences. A small group of patients with MDS who had undergone effective subcutaneous desferrioxamine (DFO) chelation for 1 to 4 years showed substantial hematologic improvements, including transfusion independence. However, because chronic lengthy subcutaneous infusions of DFO in elderly patients have logistic difficulties, this chelation therapy is generally instituted late in the clinical course. Two oral iron chelators, deferiprone (L1) and deferasirox (ICL670), provide potentially useful treatment for iron overload. This article reviews data indicating that both agents are relatively well tolerated, were at least as effective as DFO for decreasing iron burdens in comparative thalassemia trials, and (for deferiprone) were associated with improved cardiac outcomes. These outcomes could potentially alter the tissue siderosis-associated morbidity of patients with MDS, particularly those with pre-existing cardiac disease.


National Beef Tenderness Survey-2010: Warner-Bratzler shear force values and sensory panel ratings for beef steaks from United States retail and food service establishments.
The tenderness and palatability of retail and food service beef steaks from across the United States (12 cities for retail, 5 cities for food service) were evaluated using Warner-Bratzler shear (WBS) and consumer sensory panels. Subprimal postfabrication storage or aging times at retail establishments averaged 20.5 d with a range of 1 to 358 d, whereas postfabrication times at the food service level revealed an average time of 28.1 d with a range of 9 to 67 d. Approximately 64% of retail steaks were labeled with a packer/processor or store brand. For retail, top blade had among the lowest (P < 0.05) WBS values, whereas steaks from the round had the greatest (P < 0.05) values. There were no differences (P > 0.05) in WBS values between moist-heat and dry-heat cookery methods for the top round and bottom round steaks or between enhanced (contained salt or phosphate solution) or nonenhanced steaks. Food service top loin and rib eye steaks had the lowest (P < 0.05) WBS values compared with top sirloin steaks. Retail top blade steaks and food service top loin steaks received among the greatest (P < 0.05) consumer sensory panel ratings compared with the other steaks evaluated. Prime food service rib eye steaks received the greatest ratings (P < 0.05) for overall like, like tenderness, tenderness level, like juiciness, and juiciness level, whereas ungraded rib eye steaks received the lowest ratings (P < 0.05) for like tenderness and tenderness level. The WBS values for food service steaks were greater (P < 0.05) for the Select and ungraded groups compared with the Prime, Top Choice, and Low Choice groups. The WBS values and sensory ratings were comparable to the last survey, signifying that no recent or substantive changes in tenderness have occurred.


Highly solvatochromic and tunable fluorophores based on a 4,5-quinolimide scaffold: novel CDK5 probes.
Novel 4,5-quinolimide-based fluorophores are more solvatochromic and red-shifted than known naphthalimide analogues. Conjugation of one of these fluorophores to a peptide derived from CDK5 kinase demonstrated its sensitivity for monitoring the interaction with its regulatory partner p25. Introduction of the quinolimide-labelled peptide into living glioblastoma cells probed the interaction with endogenous p25.


The crystal structure of a mammalian fatty acid synthase.
Mammalian fatty acid synthase is a large multienzyme that catalyzes all steps of fatty acid synthesis. We have determined its crystal structure at 3.2 angstrom resolution covering five catalytic domains, whereas the flexibly tethered terminal acyl carrier protein and thioesterase domains remain unresolved. The structure reveals a complex architecture of alternating linkers and enzymatic domains. Substrate shuttling is facilitated by flexible tethering of the acyl carrier protein domain and by the limited contact between the condensing and modifying portions of the multienzyme, which are mainly connected by linkers rather than direct interaction. The structure identifies two additional nonenzymatic domains: (i) a pseudo-ketoreductase and (ii) a peripheral pseudo-methyltransferase that is probably a remnant of an ancestral methyltransferase domain maintained in some related polyketide synthases. The structural comparison of mammalian fatty acid synthase with modular polyketide synthases shows how their segmental construction allows the variation of domain composition to achieve diverse product synthesis.


Screening for Atrial Fibrillation: US Preventive Services Task Force Recommendation Statement.
Atrial fibrillation (AF) is the most common cardiac arrhythmia. The prevalence of AF increases with age, from less than 0.2% in adults younger than 55 years to about 10% in those 85 years or older, with a higher prevalence in men than in women. It is uncertain whether the prevalence of AF differs by race and ethnicity. Atrial fibrillation is a major risk factor for ischemic stroke and is associated with a substantial increase in the risk of stroke. Approximately 20% of patients who have a stroke associated with AF are first diagnosed with AF at the time of the stroke or shortly thereafter. To update its 2018 recommendation, the US Preventive Services Task Force (USPSTF) commissioned a systematic review on the benefits and harms of screening for AF in older adults, the accuracy of screening tests, the effectiveness of screening tests to detect previously undiagnosed AF compared with usual care, and the benefits and harms of anticoagulant therapy for the treatment of screen-detected AF in older adults. Adults 50 years or older without a diagnosis or symptoms of AF and without a history of transient ischemic attack or stroke. The USPSTF concludes that evidence is lacking, and the balance of benefits and harms of screening for AF in asymptomatic adults cannot be determined. The USPSTF concludes that the current evidence is insufficient to assess the balance of benefits and harms of screening for AF. (I statement).


Imaging pair-correlated reaction cross sections in F + CH3D(νb = 0, 1) → CH2D(ν4 = 1) + HF(ν).
The title reactions were studied in a crossed-beam experiment at collisional energies (Ec) from 0.5 to 4.7 kcal mol-1. The νb (ν4) vibrational mode denotes the bending (umbrella) motion of the CH3D reactant (CH2D product). Using a time-sliced, velocity-map imaging technique, we extracted the state-specific, pair-correlated integral and differential cross sections. As with other isotopically analogous ground-state reactions, an inverted vibrational population of the HF coproduct was observed. Both the step-like excitation function near the threshold and the oscillatory forward-backward peakings in the Ec-evolution of the two dominant pair-correlated angular distributions at lower Ec suggest a resonance-mediated, time-delay mechanism. As Ec increases, the angular distribution of the HF(ν = 2) product evolves into a smooth and broad swath in the backward hemisphere, indicative of a direct rebound mechanism. One quantum excitation of the bending modes of CH3D(νb = 1) promotes the reaction rate by two- to three-fold up to Ec = 2.1 kcal mol-1. Broadly speaking, all major findings are qualitatively in line with previous results in the reactions of the F atom with other isotopologues. However, the rainbow feature recently observed in the CH2D(00) + HF(ν = 3) product channel is entirely absent. A possible rationale is put forward, which reinforces the previous reactive rainbow conjecture and calls for future theoretical investigations.


Movement of the actin filament bundle in Mytilus sperm: a new mechanism is proposed.
An actin filament bundle approximately 2-5 microns in length is present in the sperm of the blue mussel, Mytilus. In unfired sperm this bundle extends from the midpiece through a canal in the center of the nucleus to terminate on the membrane limiting the inside of the cone-shaped acrosomal vacuole. The bundle is composed of 45-65 actin filaments which are hexagonally packed and regularly cross-bridged together to form an actin paracrystal so well ordered that it has six nearly equal faces. Upon induction of the acrosomal reaction, a needle-like process is formed in a few seconds. Within this process is the actin filament bundle which appears unchanged in filament number and packing as determined by optical diffraction methods. Using fluorescein-conjugated phalloidin we were able to establish that the bundle does not change length but instead is projected anteriorly out of the midpiece and nuclear canal like an arrow. Existing mechanisms to explain this extension cannot apply. Specifically, the bundle does not increase in length (no polymerization), does not change its organization (no change in actin twist), does not change filament number (no filament sliding), and cannot move by myosin (wrong polarity). Thus we are forced to look elsewhere for a mechanism and have postulated that at least a component of this movement, or cell elongation, is the interaction of the actin filament bundle with the plasma membrane.


Neodymium:yttrium aluminum garnet laser ventriculocordectomy in standing horses.
To develop a technique for neodymium:yttrium-aluminum-garnet (Nd:YAG) laser ventriculocordectomy in standing horses and document healing in horses undergoing laser ventriculocordectomy. 6 horses between 2 and 32 years old. Under endoscopic guidance, the left laryngeal ventricle was everted with grasping forceps and excised with an Nd:YAG laser, using 60 watts of power in a noncontact fashion (6,403 to 9,197 Joules). Following removal of the ventricle, the vocal cord was photoablated. Horses were examined endoscopically 2, 7, 14, 21, 30, and 47 days after ventriculocordectomy, and 1 horse was euthanatized on each of these days. At necropsy, the larynx was removed intact and examined grossly. Samples were collected for histologic examination of the ventriculocordectomy site. Endoscopic examination revealed granulation tissue by day 7, the start of epithelialization by day 21, and healing by day 47. At necropsy, 4 horses were found to have a small amount of ventricular mucosa remaining dorsally and 1 additional horse was found to have a mucocele. Granulation tissue was identified grossly and histologically in the horses euthanatized between 7 and 30 days after surgery. Incipient reepithelialization was evident histologically on day 14, and complete reepithelialization of the surgery site was evident by day 47. Results suggest that ventriculocordectomy can safely be performed with an Nd:YAG laser in standing horses.


Rapid testing of gene-gene interactions in genome-wide association studies of binary and quantitative phenotypes.
Genome-wide association (GWA) studies have been extremely successful in identifying novel loci contributing effects to a wide range of complex human traits. However, despite this success, the joint marginal effects of these loci account for only a small proportion of the heritability of these traits. Interactions between variants in different loci are not typically modelled in traditional GWA analysis, but may account for some of the missing heritability in humans, as they do in other model organisms. One of the key challenges in performing gene-gene interaction studies is the computational burden of the analysis. We propose a two-stage interaction analysis strategy to address this challenge in the context of both quantitative traits and dichotomous phenotypes. We have performed simulations to demonstrate only a negligible loss in power of this two-stage strategy, while minimizing the computational burden. Application of this interaction strategy to GWA studies of T2D and obesity highlights potential novel signals of association, which warrant follow-up in larger cohorts.


Lactate dehydrogenase undergoes a substantial structural change to bind its substrate.
Employing temperature-jump relaxation spectroscopy, we investigate the kinetics and thermodynamics of the formation of a very early ternary binding intermediate formed when lactate dehydrogenase (LDH) binds a substrate mimic on its way to forming the productive LDH/NADH.substrate Michaelis complex. Temperature-jump scans show two distinct submillisecond processes are involved in the formation of this ternary binding intermediate, called the encounter complex here. The on-rate of the formation of the encounter complex from LDH/NADH with oxamate (a substrate mimic) is determined as a function of temperature and in the presence of small concentrations of a protein destabilizer (urea) and protein stabilizer (TMAO). It shows a strong temperature dependence with inverse Arrhenius behavior and a temperature-dependent enthalpy (heat capacity of 610 +/- 84 cal/Mol K), is slowed in the presence of TMAO and speeded up in the presence of urea. These results suggest that LDH/NADH occupies a range of conformations, some competent to bind substrate (open structure; a minority population) and others noncompetent (closed), in fast equilibrium with each other in accord with a select fit model of binding. From the thermodynamic results, the two species differ in the rearrangement of low energy hydrogen bonds as would arise from changes in internal hydrogen bonding and/or increases in the solvation of the protein structure. The binding-competent species can bind ligand at or very near diffusion-limited speeds, suggesting that the binding pocket is substantially exposed to solvent in these species. This would be in contrast to the putative closed structure where the binding pocket resides deep within the protein interior.


Complexity measurement based on information theory and kolmogorov complexity.
In the past decades many definitions of complexity have been proposed. Most of these definitions are based either on Shannon's information theory or on Kolmogorov complexity; these two are often compared, but very few studies integrate the two ideas. In this article we introduce a new measure of complexity that builds on both of these theories. As a demonstration of the concept, the technique is applied to elementary cellular automata and simulations of the self-organization of porphyrin molecules.


Chloride channel ClC-3 in gills of the euryhaline teleost, Tetraodon nigroviridis: expression, localization and the possible role of chloride absorption.
Previous studies have reported the mechanisms of ion absorption and secretion by diverse membrane transport proteins in gills of various teleostean species. To date, however, the chloride channel expressed in the basolateral membrane of mitochondrion-rich (MR) cells for Cl(-) uptake in freshwater (FW) fish is still unknown. In this study, the combination of bioinformatics tools [i.e. National Center for Biotechnology Information (NCBI) database, Tetraodon nigroviridis (spotted green pufferfish) genome database (Genoscope), BLAT and BLASTn] were used to identify the gene of ClC-3 (TnClC-3), a member of the CLC chloride channel family in the T. nigroviridis genome. RT-PCR analysis revealed that the gene encoding for the ClC-3 protein was widely expressed in diverse tissues (i.e. gill, kidney, intestine, liver and brain) of FW- and seawater (SW)-acclimated pufferfish. In whole-mount double immunofluorescent staining, branchial ClC-3-like immunoreactive protein was localized to the basolateral membrane of Na(+)/K(+)-ATPase (NKA) immunoreactive cells in both the FW- and SW-acclimated pufferfish. In response to salinity, the levels of transcript of branchial TnClC-3 were similar between FW and SW fish. Moreover, the membrane fraction of ClC-3-like protein in gills was 2.7-fold higher in FW compared with SW pufferfish. To identify whether the expression of branchial ClC-3-like protein specifically responded to lower environmental [Cl(-)], the pufferfish were acclimated to artificial waters either with a normal (control) or lower Cl(-) concentration (low-Cl). Immunoblotting of membrane fractions of gill ClC-3-like protein showed the expression was about 4.3-fold higher in pufferfish acclimated to the low-Cl environment than in the control group. Furthermore, branchial ClC-3-like protein was rapidly elevated in response to acute changes of environmental salinity or [Cl(-)]. Taken together, pufferfish ClC-3-like protein was expressed in the basolateral membrane of gill MR cells, and the protein amounts were stimulated by hyposmotic and low-Cl environments. The enhancement of ClC-3-like protein may trigger the step of basolateral Cl(-) absorption of the epithelium to carry out iono- and osmoregulatory functions of euryhaline pufferfish gills.


A new curriculum using active learning methods and standardized patients to train residents in smoking cessation.
Physicians can play a key role in smoking cessation but often fail to advise smokers effectively, mainly because they lack counseling skills. We need effective training programs starting during residency to improve physicians' smoking cessation interventions and smokers' quit rates. To achieve this goal, we developed a curriculum using active learning methods and the stages-of-change model. A randomized trial demonstrated that this program increased the quality of physician's counseling and smokers' quit rates at 1 year. This paper describes the educational content and methods of this program. Participants learn to assess smokers' stage of change, to use counseling strategies matching the smoker's stage, and to prescribe pharmacological therapy. This 2 half-day training program includes observation of video-clips, interactive workshops, role plays, practice with standardized patients, and written material for physicians and patients. Participants reached learning objectives and appreciated the content and active methods of the program.


A comparison of outcomes among hospital survivors with and without severe comorbidity admitted to the intensive care unit.
Little is known about the experiences of patients with severe comorbidity discharged from Intensive Care Units (ICUs). This project aimed to determine the effects of an ICU stay for patients with severe comorbidity by comparing 1) quality of life (QOL), 2) the symptom profile of hospital survivors and 3) health service use after hospital discharge for patients admitted to ICU with and without severe comorbidity. A case-control study was used. Patients with severe comorbidity were matched to a contemporaneous cohort of ICU patients by age and severity of illness. Assessment tools were the Medical Outcome Study 36-item short-form and European Organisation for Research and Treatment of Cancer QLQ-C15-PAL questionnaires for QOL and the Symptom Assessment Scale for symptom distress. A proportional odds assumption was performed using an ordinal regression model. The difference in QOL outcome was the dependent variable for each pair. Health service use after discharge from ICU was monitored with patient diaries. Patients aged 18+ years admitted to an ICU in a metropolitan teaching hospital between 2011 and 2012 were included. We recruited 30 cases and 30 controls. QOL improved over the six months after hospital discharge for patients with and without severe comorbidity (P <0.01) within the groups but there was no difference found between the groups (P >0.3). There was no difference in symptoms or health service use between patients with and without severe comorbidity. ICU admission for people with severe comorbidity can be appropriate to stabilise the patient's condition and is likely to be followed by some overall improvement over the six months after hospital discharge.


Magnetic determination of the relationship between the S-T segment shift and the injury current produced by coronary artery occlusion.
Both the S-T segment shift and the injury current were measured using the direct-current magnetocardiogram (d-c MCG) in seven dogs undergoing coronary artery occlusion. The purpose of the measurements was to clarify the origin of the S-T shift in acute ischemia and infarction. Previous measurements, consisting of d-c electrograms recorded from the exposed epicardial surface in situ, are partially inconsistent; also, they are not necessarily representative of the surface electrocardiogram (ECG), which sums broadly over the myocardium. The d-c MCG allows steady myocardial currents in the intact torso to the measured externally; because the d-c MCG sums broadly over these currents, conclusions drawn from it are applicable to the ECG. Coronary artery occlusion was produced by inflating a tube which, about 1 week earlier, had been surgically installed around the artery and exteriorized. During occlusions carried out in the MIT magnetically shielded room, a sensitive magnetometer recorded the d-c MCG at various locations around the torso. Within 20 seconds after occlusion, equal and opposite S-T segment and base-line (d-c) shifts appeared on the d-c MCG; these shifts were maintained for at least 15 minutes, after which they slowly decreased. Therefore, during the acute ischemia produced by these occlusions, the S-T shift is a secondary result of a primary injury current that is interrupted during the S-T interval.


Immunophenotyping of the human bulge region: the quest to define useful in situ markers for human epithelial hair follicle stem cells and their niche.
Since the discovery of epithelial hair follicle stem cells (eHFSCs) in the bulge of human hair follicles (HFs) an important quest has started: to define useful markers. In the current study, we contribute to this by critically evaluating corresponding published immunoreactivity (IR) patterns, and by attempting to identify markers for the in situ identification of human eHFSCs and their niche. For this, human scalp skin cryosections of at least five different individuals were examined, employing standard immunohistology as well as increased sensitivity methods. Defined reference areas were compared by quantitative immunohistochemistry for the relative intensity of their specific IR. According to our experience, the most useful positive markers for human bulge cells turned out to be cytokeratin 15, cytokeratin 19 and CD200, but were not exclusive, while beta1 integrin and Lhx2 IR were not upregulated by human bulge keratinocytes. Absent IR for CD34, connexin43 and nestin on human bulge cells may be exploited as negative markers. alpha6 integrin, fibronectin, nidogen, fibrillin-1 and latent transforming growth factor (TGF)-beta-binding protein-1 were expressed throughout the connective tissue sheath of human HFs. On the other hand, tenascin-C was upregulated in the bulge and may thus constitute a component of the bulge stem cell niche of human HFs. These immunophenotyping results shed further light on the in situ expression patterns of claimed follicular 'stem cell markers' and suggest that not a single marker alone but only the use of a limited corresponding panel of positive and negative markers may offer a reasonable and pragmatic compromise for identifying human bulge stem cells in situ.


The role of Microsporidia in the pathogenesis of HIV-related chronic diarrhea.
To determine whether infection with Microsporidia leads to diarrhea in patients with human immunodeficiency virus (HIV) infection. Case-control study. Primary care outpatient HIV clinic at a Veterans Affairs medical center. One hundred six HIV-infected men, 55 with and 51 without chronic diarrhea. Each patient underwent upper endoscopy and flexible sigmoidoscopy to obtain duodenal, rectal, and sigmoid colonic biopsy specimens. At the time of endoscopy, a fresh stool was obtained for culture, ova and parasite assessment, and Cryptosporidium examination. Biopsy tissue was examined using electron microscopy to detect Microsporidia. The microsporidian parasite Enterocytozoon bieneusi was detected in the duodenal biopsy specimens of 31 of 106 men (29%); 24 of 106 men (23%) had other enteric pathogens. No significant difference was observed in the occurrence of microsporidiosis in patients with (18 of 55 [33%]) and without (13 of 51 [25%]) chronic diarrhea (odds ratio, 1.42; 95% CI, 0.61 to 3.31). A similar nonsignificant difference was observed after controlling for CD4 count and other enteric pathogens (odds ratio, 1.66; 95% CI, 0.68 to 4.06). Among patients with microsporidiosis, no difference was observed in the intensity of infection (defined by the presence of few, moderate, or abundant organisms) among cases and controls (P > 0.2). This is the first report to document the presence of E. bieneusi in HIV-positive patients without gastrointestinal symptoms. No significant difference was observed in the occurrence of E. bieneusi infection in HIV-infected patients with or without chronic diarrhea. Thus, the association between microsporidiosis and diarrhea, if one exists, may not be as strong as is currently believed.


Service Delivery Experiences and Intervention Needs of Military Families with Children with ASD.
The purpose of this study was to describe the experiences of military families with children with autism spectrum disorder (ASD) specifically as it relates to relocation. Online survey methodology was used to gather information from military spouses with children with ASD. The finalized dataset included 189 cases. Descriptive statistics and frequency analyses were used to examine participant demographics and service delivery questions. Results indicated the larger sample of military spouses largely confirmed the experiences reported qualitatively in previous studies and contributed information that was previously unknown about variables associated with the access, availability, quality, and frequency of intervention services for military families with children with ASD.


Rhesus macaque MHC class I molecules present HLA-B-like peptides.
SIV-infected Indian rhesus macaques (Macaca mulatta) are an important animal model for humans infected with HIV. Understanding macaque (M. mulatta class I (Mamu)) MHC class I-peptide binding facilitates the comparison of SIV- and HIV-specific cellular immune responses. In this study, we characterized the endogenous peptide-binding properties of three Mamu-A (A*02, A*08, A*11) and three Mamu-B (B*01, B*03, B*12) class I molecules. Motif comparisons revealed that five of the six macaque class I molecules (A*02, A*08, A*11, B*01, and B*03) have peptide-binding motifs similar to those of human class I molecules. Of the 65 macaque endogenous peptide ligands that we sequenced by tandem mass spectroscopy, 5 were previously eluted from HLA class I molecules. Nonamers predominated among the individual ligands, and both the motifs and the individual ligands indicated P2, P9, and various ancillary anchors. Interestingly, peptide binding of the Mamu-A and Mamu-B molecules exhibited cross-species peptide-presentation overlap primarily with HLA-B molecules. Indeed, all of the macaque class I molecules appeared HLA-B-like in peptide presentation. Remarkably, the overlap in macaque- and HLA-peptide presentation occurred despite divergent class I peptide-binding grooves. Macaque and human class I differing by up to 42 aa (13-23%) within the alpha-1 and alpha-2 domains, including substantial divergence within specificity pockets A-F, bound the same endogenous peptide. Therefore, endogenous peptide characterization indicates that macaque class I molecules may be the functional equivalents of HLA-B molecules.


Percutaneous tracheostomy for long-term ventilated COVID-19-patients: rationale and first clinical-safe for all-experience.
COVID-19 infection has resulted in thousands of critically ill patients admitted to ICUs and treated with mechanical ventilation. Percutaneous tracheostomy is a well-known technique utilised as a strategy to wean critically ill patients from mechanical ventilation. Worldwide differences exist in terms of methods, operators, and settings, and questions remain regarding timing and indications. If tracheostomy is to be performed in COVID-19 patients, a safe environment is needed for optimal care. We present a guidewire dilating forceps tracheostomy procedure in COVID-19 patients that was optimised including apnoea-moments, protective clothing, checklists, and clear protocols. We performed a retrospective analysis of the outcome after tracheostomy in COVID-19 patients between March 2020 and May 2020. The follow-up of the first 16 patients, median age 62 years, revealed a median intubation time until tracheostomy of 18 days and median cannulation time of 20 days. The overall perioperative complication rate and complication rate while cannulated was 19%, mainly superficial bleeding. None of the healthcare providers involved in performing the procedure developed any symptoms of the disease. This COVID-19-centred strategy based on flexibility, preparation, and cooperation between healthcare providers with different backgrounds facilitated percutaneous tracheostomy in COVID-19 patients without an increase in the overall complication rate or evidence of risk to healthcare providers. Our findings provide initial evidence that tracheostomy can be performed safely as a standard of care for COVID-19 patients requiring prolonged mechanical ventilation as was standard practice in ICU patients prior to the COVID-19 pandemic to promote ventilator weaning and patient recovery.


Clinical experience of two Israeli medical centers with the implantable loop recorder in patients with syncope: from diagnosis to treatment.
The implantable loop recorder (ILR) is an important tool for the evaluation of unexplained syncope, particularly in cases of rarely occurring arrhythmia. To review the clinical experience of two Israeli medical centers with the ILR. We reviewed the medical records of patients with unexplained syncope evaluated with the ILR at Rabin Medical Center (2006-2010) and Wolfson Medical Center (2000-2009). The study group included 75 patients (44 males) followed for 11.9 +/- 9.5 months after ILR implantation. Patients' mean age was 64 +/- 20 years. The ILR identified an arrhythmic mechanism of syncope in 20 patients (17 bradyarrhythmias, 3 tachyarrhythmias) and excluded arrhythmias in 12, for a diagnostic yield of 42.7%. It was not diagnostic in 17 patients (22.7%) at the time of explant; 26 patients (34.7%) were still in follow-up. In two patients ILR results that were initially negative were reversed by later ILR tracings. The patients with bradyarrhythmias included 9 of 16 (56.3%) with surface electrocardiogram conduction disturbances and 2 of 12 (16.7%) with negative findings on carotid sinus massage. All bradyarrhythmic patients received pacemakers; the seven patients for whom post-intervention data were available had no or mild symptoms. The ILR has a high diagnostic yield. Pre-ILR findings correlating with the ILR results are conduction disturbances (positive predictor of arrhythmia) and negative carotid sinus massage results (negative predictor of arrhythmia). Proper patient instruction is necessary to obtain accurate results. Caution is advised when excluding an arrhythmia on the basis of ILR tracings, and long-term follow-up is warranted.


Enhanced expression of prostate-specific membrane antigen gene in prostate cancer as revealed by in situ hybridization.
Recently, the cDNA encoding a novel candidate for prostate cancer-specific antigen, named prostate-specific membrane antigen (PSM), was cloned from the LNCaP prostate cancer cell line (R. S. Israeli, C. T. Powell, W. R. Fair, and W. D. W. Heston, Cancer Res., 53: 227-230,1993). More recently, they also identified an alternatively spliced variant of PSM in normal prostate tissues (S. L. Su, I-P. Huang, W. R. Fair, C. T. Powell, and W. D. W. Heston, Cancer Res., 55: 1441-1443, 1995). The cDNA of this variant, named PSM', lacks 266 nucleotides present in PSM cDNA, so the transcripts derived from this particular nucleotide sequence can be regarded as PSM-specific transcripts. In this study, we investigated the expression of PSM-specific transcripts in 15 specimens of prostate cancer obtained by needle biopsy using in situ hybridization with a newly developed RNA probe. PSM-specific transcripts were detected in most of the carcinoma cells in all of the specimens examined, and the level of expression was higher in carcinoma cells from hormone-refractory patients than in the cells of those who showed a good response to hormonal therapy. In addition, increased expression of PSM-specific transcripts was also associated with an increased Gleason score. In the normal prostate, on the other hand, PSM-specific transcripts were limited to the basal cells of the prostate glands. These results clearly show that expression of PSM-specific transcripts is closely associated with malignant transformation of the prostate; thus, in situ hybridization for detection of the transcripts is useful for the diagnosis of prostate cancer.


Caregiver Contribution to Heart Failure Self-Care (CACHS).
While caregivers (CGs) make an important contribution to the self-care of heart failure (HF) patients, there are no reliable and valid tools for measuring such contributions. Current interventions that strive to optimize patient outcomes through self-care strategies neglect to account for CG contributions, a potential confounder on outcomes. The aim of the study was to develop an instrument that measures CG contributions to HF patients' self-care. The study design follows an established process for instrument development. A systematic literature review and semi-structured interviews of CGs were conducted to identify measureable CG activities. Items were derived from thematic analysis of CG narratives. A content validity index was computed for each item (I-CVI). Items with an I-CVI of >0·70 were retained. Items with an I-CVI of 0·50-0·70 were revised for clarification and items with an I-CVI <0·5 were discarded, except in instances where fulsome theoretical or empirical evidence supported their retention. 14 CGs completed interviews and 10 CGs with 4 expert nurses completed I-CVI testing. Major interview themes included arranging appointments, medication adherence, monitoring, coordinating care, encouraging independence and taking action. A total of 36 items were constructed and underwent I-CVI testing. Following I-CVI testing, 27 items were retained, seven items were retained after revision based on CG feedback and two items were removed. This newly developed 34-item questionnaire represents current literature, CGs' experiences, excellent I-CVI scores and ready for further psychometric testing.


The PnrA (Tp0319; TmpC) lipoprotein represents a new family of bacterial purine nucleoside receptor encoded within an ATP-binding cassette (ABC)-like operon in Treponema pallidum.
Treponema pallidum, the bacterial agent of syphilis, cannot be cultivated in vitro. This constraint has severely impeded the study of the membrane biology of this complex human pathogen. A structure-to-function approach thus was adopted as a means of discerning the likely function of Tp0319, a 35-kDa cytoplasmic membrane-associated lipoprotein of T. pallidum formerly designated as TmpC. A 1.7-A crystal structure showed that recombinant Tp0319 (rTp0319) consists of two alpha/beta domains, linked by three crossovers, with a deep cleft between them akin to ATP-binding cassette (ABC) receptors. In the cleft, a molecule of inosine was bound. Isothermal titration calorimetry demonstrated that rTp0319 specifically binds purine nucleosides (dissociation constant (Kd) approximately 10(-7) M). This predilection for purine nucleosides by rTp0319 is consistent with its likely role as a receptor component of a cytoplasmic membrane-associated transporter system. Reverse transcription-PCR analysis of RNA isolated from rabbit tissue-extracted T. pallidum additionally showed that tp0319 is transcriptionally linked to four other downstream open reading frames, thereby supporting the existence of an ABC-like operon (tp0319-0323). We herein thus re-name tp0319 as purine nucleoside receptor A (pnrA), with its operonic partners tp0320-0323 designated as pnrB-E, respectively. Our study not only infers that PnrA transports purine nucleosides essential for the survival of T. pallidum within its obligate human host, but to our knowledge, this is the first description of an ABC-type nucleoside transport system in any bacterium. PnrA has been grouped with a functionally uncharacterized protein family (HBG016869), thereby implying that other members of the family may have similar nucleoside-binding function(s).


miR-31 functions as a negative regulator of lymphatic vascular lineage-specific differentiation in vitro and vascular development in vivo.
The lymphatic vascular system maintains tissue fluid homeostasis, helps mediate afferent immune responses, and promotes cancer metastasis. To address the role microRNAs (miRNAs) play in the development and function of the lymphatic vascular system, we defined the in vitro miRNA expression profiles of primary human lymphatic endothelial cells (LECs) and blood vascular endothelial cells (BVECs) and identified four BVEC signature and two LEC signature miRNAs. Their vascular lineage-specific expression patterns were confirmed in vivo by quantitative real-time PCR and in situ hybridization. Functional characterization of the BVEC signature miRNA miR-31 identified a novel BVEC-specific posttranscriptional regulatory mechanism that inhibits the expression of lymphatic lineage-specific transcripts in vitro. We demonstrate that suppression of lymphatic differentiation is partially mediated via direct repression of PROX1, a transcription factor that functions as a master regulator of lymphatic lineage-specific differentiation. Finally, in vivo studies of Xenopus and zebrafish demonstrated that gain of miR-31 function impaired venous sprouting and lymphatic vascular development, thus highlighting the importance of miR-31 as a negative regulator of lymphatic development. Collectively, our findings identify miR-31 is a potent regulator of vascular lineage-specific differentiation and development in vertebrates.


Promoter polymorphisms in the β-2 adrenergic receptor are associated with drug-induced gene expression changes and response in acute lymphoblastic leukemia.
We investigated whether genetic polymorphisms in the promoter region of the proapoptotic β-2 adrenergic receptor gene (ADRB2) influence treatment-induced changes in ADRB2 expression in leukemia cells and response to chemotherapy. The ADRB2 promoter region was genotyped in germline DNA from 369 children with acute lymphoblastic leukemia (ALL). For 95 of the patients, sufficient RNA was available before and after in vivo treatment to assess treatment-induced gene expression changes in ALL cells. After treatment, the median ADRB2 mRNA expression was ninefold lower in leukemia cells of patients who ultimately relapsed as compared with patients who remained in continuous complete remission (CCR). Polymorphisms in the ADRB2 promoter were significantly linked to methotrexate (MTX)-induced upregulation in ADRB2 gene expression in ALL cells. Moreover, the ADRB2 promoter haplotype was significantly related to early treatment response in 245 children with ALL who received uniform treatment. We conclude that germline polymorphisms in ADRB2 are linked to the antileukemic effects of ALL chemotherapy.


Effect of bonded gold inlays on fracture resistance of teeth.
The purpose of this study was to determine if bonding gold inlays to tooth structure with an adhesive resin cement would increase the fracture resistance of restored teeth. Extracted paired maxillary premolars were prepared for mesio-occlusodistal inlays, and the inlays were cast in type II gold. In one tooth of each pair, the inlay was sandblasted with aluminium oxide, tin plated, and cemented with an adhesive resin into the etched preparation. For the other (control) tooth in each pair, the inlay was sandblasted and then cemented into the preparation with zinc phosphate cement. The teeth were thermocycled and loaded until fracture. The teeth in the bonded group had a statistically significantly higher fracture resistance than did the teeth in the control group. Scanning electron microscopic examination revealed that failure in the bonded group occurred predominantly within the resin.


Enhancement in pump inversion efficiency at 980 nm in Er(3+), Er(3+)/Eu(3+)+ and Er(3+)/Ce(3+) doped tellurite glass fibers.
Amplification properties have been compared in Er(3+), Er(3+)/Eu(3+) and Er(3+)/Ce(3+) doped tellurite glass fibers using a 980 nm pumping scheme. The pump efficiency has been compared in the 3 types of fibers. Er(3+) ion upconversion in bulk glasses and fibers in visible range has been measured and the Er(3+) ion IR fluorescence intensity and lifetimes have been recorded to understand the amplification characteristics. Codoping with Ce3+ is more efficient in Er(3+) doped tellurite fibre.


Bone marrow aspirate microscopy v. bone marrow trephine biopsy microscopy for detection of Mycobacterium tuberculosis infection.
Tuberculosis (TB) remains a global health problem. According to the 2013 Global Report on Tuberculosis, 8.6 million people developed TB in 2012 and 1.3 million died from the disease. An estimated 13% of people who developed TB in 2012 were HIV-positive, and 75% of these lived in Africa. While pulmonary TB is the commonest form of Mycobacterium tuberculosis infection, extrapulmonary TB is increasingly being detected in HIV-positive patients. Definitive diagnosis of disseminated TB is a challenge owing to atypical presentations and diagnostic difficulties (negative chest radiograph and sputum microscopy and culture). A rapid diagnosis of disseminated TB is desirable, as early initiation of treatment can reduce mortality. Although TB culture is the gold standard for diagnosis of TB, it has a long turnaround time (up to 6 weeks). To identify a potentially faster and more effective diagnostic strategy for disseminated TB. A retrospective 18-month review, conducted at a tertiary hospital, comparing histological findings of an auramine O-stained bone marrow aspiration (BMA) smear and a bone marrow trephine (BMT) biopsy specimen with the gold standard of TB culture. Microscopic examination of BMA smears and BMT biopsy specimens offers a rapid diagnostic strategy, with results available on the same day for the former and within 4 days for the latter. BMT histological examination had a significantly higher detection rate than BMA auramine O staining compared with TB culture. We recommend that BMT biopsies remain an essential part of the diagnostic work-up for disseminated TB.