A comparative evaluation of intrathecal bupivacaine alone, sufentanil or butorphanol in combination with bupivacaine for endoscopic urological surgery.
The objective of the present study was to compare the onset, degree and recovery time of sensory and motor block and hemodynamic effects of intrathecal bupivacaine alone and bupivacaine with sufentanil or butorphanol in endoscopic urological surgeries. In a randomized, double-blind study, 90 patients of either sex and age, belonging to ASA Grades I and II, scheduled for elective endoscopic urological surgeries under spinal anesthesia, were allocated into three groups of 30 each. Patients received either 2.5 ml of 0.5% hyperbaric buypivacaine 12.5 mg (Group A), 1.5 ml of 0.5% hyperbaric bupivacaine 7.5 mg with 10 μg sufentanil (Group B) or 1.5 ml of 0.5% hyperbaric bupivacaine 7.5 mg with 25 μg butorphanol (Group C). Vital parameters, level, duration and regression of sensory block and motor block and side-effects were recorded and compared. Analysis of variance (ANOVA), post hoc test and Chi-square test were used. Intrathecal addition of sufentanil/butorphanol prolonged the duration of sensory block (DOSB) compared with bupivacaine alone (DOSB being 156.83±23.83 min, 170.87 ± 22.21 min and 171.17 ± 23.99 min in groups A, B and C, respectively) without altering the duration of motor blockade. Bromage score 3 was achieved in 100%, 90% and 54.4% patients in groups A, B and C, respectively. The time to first request for analgesia was 112 ± 46.3 min, 323 ± 65.0 min and 299 ± 73.9 min in groups A, B and C, respectively. Complications were reduced by the addition of butorphanol, which also has a lower tendency than sufentanil to produce pruritus (60%). The analgesia was significantly prolonged in groups B and C; group C had a less-intense motor block. Complications were reduced by the addition of butorphanol, which also has a lower tendency than sufentanil to produce pruritus. Thus, this combination of butorphanol with low-dose bupivacaine is especially beneficial in the geriatric group of patients who have multiple co-morbid conditions.


Origin of multiple periodicities in the Fourier power spectra of the Plasmodium falciparum genome.
Fourier transforms and their associated power spectra are used for detecting periodicities and protein-coding genes and is generally regarded as a well established technique. Many of the periodicities which have been found with this method are quite well understood such as the periodicity of 3 nt which is associated to codon usage. But what is the origin of the peculiar frequency multiples k/21 which were reported for a tiny section of chromosome 2 in P. falciparum? Are these present in other chromosomes and perhaps in related organisms? And how should we interpret fractional periodicities in genomes? We applied the binary indicator power spectrum to all chromosomes of P. falciparum, and found that the frequency overtones k/21 are present only in non-coding sections. We did not find such frequency overtones in any other related genomes. Furthermore, the frequency overtones were identified as artifacts of the way the genome is encoded into a numerical sequence, that is, they are frequency aliases. By choosing a different way to encode the sequence the overtones do not appear. In view of these results, we revisited early applications of this technique to proteins where frequency overtones were reported. Some authors hinted recently at the possibility of mapping artifacts and frequency aliases in power spectra. However, in the case of P. falciparum the frequency aliases are particularly strong and can mask the 1/3 frequency which is used for gene detecting. This shows that albeit being a well known technique, with a long history of application in proteins, few researchers seem to be aware of the problems represented by frequency aliases.


Current status of endocrine therapy for metastatic breast cancer.
Hormonal manipulation is currently the mainstay of palliative care for metastatic breast cancer because it is well tolerated and produces significant responses in approximately one-third of unselected patients. Tamoxifen, a nonsteroidal antiestrogen, is currently considered first-line therapy. Second-line agents include progestins and aromatase inhibitors. New agents, such as the "pure" antiestrogens and the gonadotropin-releasing hormone (GnRH) agonists, are being tested. Other approaches for affecting the hormonal milieu are also under investigation, including combinations of hormonal agents, hormonal agents plus biologics, and hormonal agents plus antiproliferative agents. This review will address the basis for endocrine therapy and possible mechanisms of hormonal resistance, currently available agents and newer ones on the horizon, and areas of future interest.


Dietary acrylamide and human cancer: a systematic review of literature.
Cancer remains the second leading cause of death in the United States, and the number of cases is expected to continue to rise worldwide. Cancer prevention strategies are crucial for reducing the cancer burden. The carcinogenic potential of dietary acrylamide exposure from cooked foods is unknown. Acrylamide is a by-product of the common Maillard reaction where reducing sugars (i.e., fructose and glucose) react with the amino acid, asparagine. Based on the evidence of acrylamide carcinogenicity in animals, the International Agency for Research on Cancer has classified acrylamide as a group 2A carcinogen for humans. Since the discovery of acrylamide in foods in 2002, a number of studies have explored its potential as a human carcinogen. This article outlines a systematic review of dietary acrylamide and human cancer, acrylamide exposure and internal dose, exposure assessment methods in the epidemiologic studies, existing data gaps, and future directions. A majority of the studies reported no statistically significant association between dietary acrylamide intake and various cancers, and few studies reported increased risk for renal, endometrial, and ovarian cancers; however, the exposure assessment has been inadequate leading to potential misclassification or underestimation of exposure. Future studies with improved dietary acrylamide exposure assessment are encouraged.


Calcium affinity of human α-actinin 1.
Due to alternative splicing, the human ACTN1 gene codes for three different transcripts of α-actinin; one isoform that is expressed only in the brain and two with a more general expression pattern. The sequence difference is located to the C-terminal domains and the EF-hand motifs. Therefore, any functional or structural distinction should involve this part of the protein. To investigate this further, the calcium affinities of these three isoforms of α-actinin 1 have been determined by isothermal calorimetry.


Structural rearrangements in the active site of the Thermus thermophilus 16S rRNA methyltransferase KsgA in a binary complex with 5'-methylthioadenosine.
Posttranscriptional modification of ribosomal RNA (rRNA) occurs in all kingdoms of life. The S-adenosyl-L-methionine-dependent methyltransferase KsgA introduces the most highly conserved rRNA modification, the dimethylation of A1518 and A1519 of 16S rRNA. Loss of this dimethylation confers resistance to the antibiotic kasugamycin. Here, we report biochemical studies and high-resolution crystal structures of KsgA from Thermus thermophilus. Methylation of 30S ribosomal subunits by T. thermophilus KsgA is more efficient at low concentrations of magnesium ions, suggesting that partially unfolded RNA is the preferred substrate. The overall structure is similar to that of other methyltransferases but contains an additional alpha-helix in a novel N-terminal extension. Comparison of the apoenzyme with complex structures with 5'-methylthioadenosine or adenosine bound in the cofactor-binding site reveals novel features when compared with related enzymes. Several mobile loop regions that restrict access to the cofactor-binding site are observed. In addition, the orientation of residues in the substrate-binding site indicates that conformational changes are required for binding two adjacent residues of the substrate rRNA.


An investigation of outpatient children's blood lead level in Wuhan China.
Blood lead levels (BLLs) and possible influencing factors in children in Wuhan China were investigated in order to understand current lead pollution exposure and provide a scientific basis for prevention and policy making. BLL data were collected from 15,536 out-patients in Wuhan Children Hospital in 2012 full year. All of them were under 18 years of age (Mean ± SD: 4.32 ± 3.2, 64.4% boys). The BLLs were measured by an atomic absorption spectrometry (BH2100). The geometric mean of BLLs for all the subjects was 44.75 µg/L (95%CI: 44.46 µg/L - 45.05 µg/L), much lower than that reported in previous studies. The prevalence of the elevated BLLs (≥ 100 µg/L) in the children tested was 2% in 2012 and the prevalence of BLLs (≥ 50 µg/L) was 44%. Age and sex could be possible influencing factors for BLLs in the children (p<0.001). In addition, the BLLs in different seasons were different (p<0.001). These results demonstrate that BLLs have significantly decreased in children in Wuhan during recent years. However, we should continuously pay attention to lead pollution and emphasize that prevention is much more important than treatment for controlling children's BLLs.


Techniques and Perforator Selection in Single, Dominant DIEP Flap Breast Reconstruction: Algorithmic Approach to Maximize Efficiency and Safety.
Perforator selection is critical to deep inferior epigastric perforator (DIEP) flap harvest. Commitment to a single perforator has the potential benefit of a simpler dissection, but may increase fat necrosis or perfusion-related complications compared with multiple perforator harvest. A 3-year retrospective study was carried out of all patients who underwent DIEP flap breast reconstruction performed by the senior author (M.S.-C). Data were collected on patient demographics and surgical outcomes. One hundred eighty-three flaps were performed (105 patients) over 3 years. One hundred fifty-six bilateral (78 patients) and 24 unilateral flaps were included in the final study. Mean age was 47.8 ± 8.4 years and mean body mass index was 29.1 ± 5.3 kg/m. Seventy-five percent of flaps were based on single dominant perforators. Single perforators were used in 33.3 percent of flaps weighing over 1000 g, 80 and 74 percent of flaps weighing 500 to 1000 g and less than 500 g, respectively (p = 0.01). There were no differences in overall complications between single- versus multiple-perforator DIEP flaps. Neither body mass index nor flap weight posed additional risk to overall complications. Conversion to a muscle-sparing flap was 9.4 percent. The authors present an algorithm for perforator selection, stepwise approach to flap harvest, and considerations for intraoperative decision-making in DIEP flap reconstruction. Single-dominant perforator flaps can be safely performed, but inclusion of the largest perforator is critical to flap perfusion. Additional perforators must be weighed against the associated tradeoff with donor-site morbidity. The threshold for conversion to a muscle-sparing flap is reduced with increased clinical experience. Therapeutic, III.


Selective targeting of nitric oxide synthase inhibitors to system y+ in activated macrophages.
Amino acid transport systems mediating uptake of nitric oxide (NO) synthase inhibitors were characterized in the murine macrophage cell line J774. Treatment of J774 cells with bacterial endotoxin (LPS, 1 microgram ml-1, 24 h) selectively increased the transport capacity for NG-monomethyl-L-[14C]arginine (L-NMMA), whereas transport of NG-nitro-L-[3H]arginine (L-NNA) was unaffected. Inhibition studies established that the cationic transport system y+ mediates uptake of L-arginine, L-NMMA and NG-iminoethyl-L-ornithine (L-NIO). A neutral transporter, with low substrate specificity and insensitive to LPS, mediates uptake of L-citrulline, L-NNA and its methyl ester L-NAME. We conclude that enhanced expression of the y+ transporter in LPS-stimulated macrophages may facilitate the targeting of selective inhibitors of inducible NO synthase to activated cells generating NO in endotoxin shock.


De novo and molecular target-independent discovery of orally bioavailable lead compounds for neurological disorders.
There is immediate potential to enhance success and innovation in drug development by pairing newly emerging approaches in medicinal chemistry and computational biology with knowledge gained from the recent era of high throughput screens and the early years of modern drug discovery when in vivo efficacy was an early "Go/No Go" project management decision. Focused, in-parallel synthetic chemistry platforms, combined with computational analyses serving as decision aids in planning, minimize the total number of compounds synthesized while maximizing the probability of creating bioavailable compounds that sample diverse chemical space. Incorporating a hierarchal strategy that emphasizes early selection of synthesized compounds based on biological or biophysical endpoints presents fewer and more relevant compounds for secondary evaluation of in vivo efficacy using animal screens with disease relevant or clinically translatable endpoints. We summarize here an interdisciplinary approach at the chemistry-biology interface that is used for the rapid discovery of novel lead compounds for neurodegenerative disorders, such as Alzheimer's disease (AD). The chemistry platform uses established chemistries amenable to in-parallel strategies to create synthetic diversifications of the privileged pyridazine chemotype that sample a restricted chemical space. The hierarchal biology platform uses primary screens for in vitro activity and selectivity with the target cell type, and rapid secondary screens for in vivo efficacy and toxicity in animal models with good phenotypic penetrance for disease relevant pathophysiological endpoints or clinically translatable surrogate endpoints. For the AD case study, novel lead compounds were developed in less than two years by a small academic group, and corporate sponsored clinical trials are planned.


Early Chk1 phosphorylation is driven by temozolomide-induced, DNA double strand break- and mismatch repair-independent DNA damage.
Temozolomide (TMZ) is a DNA methylating agent used to treat brain cancer. TMZ-induced O6-methylguanine adducts, in the absence of repair by O6-methylguanine DNA methyltransferase (MGMT), mispair during DNA replication and trigger cycles of futile mismatch repair (MMR). Futile MMR in turn leads to the formation of DNA single and double strand breaks, Chk1 and Chk2 phosphorylation/activation, cell cycle arrest, and ultimately cell death. Although both pChk1 and pChk2 are considered to be biomarkers of TMZ-induced DNA damage, cell-cycle arrest, and TMZ induced cytotoxicity, we found that levels of pChk1 (ser345), its downstream target pCdc25C (ser216), and the activity of its upstream activator ATR, were elevated within 3 hours of TMZ exposure, long before the onset of TMZ-induced DNA double strand breaks, Chk2 phosphorylation/activation, and cell cycle arrest. Furthermore, TMZ-induced early phosphorylation of Chk1 was noted in glioma cells regardless of whether they were MGMT-proficient or MGMT-deficient, and regardless of their MMR status. Early Chk1 phosphorylation was not associated with TMZ-induced reactive oxygen species, but was temporally associated with TMZ-induced alkalai-labile DNA damage produced by the non-O6-methylguanine DNA adducts and which, like Chk1 phosphorylation, was transient in MGMT-proficient cells but persistent in MGMT-deficient cells. These results re-define the TMZ-induced DNA damage response, and show that Chk1 phosphorylation is driven by TMZ-induced mismatch repair-independent DNA damage independently of DNA double strand breaks, Chk2 activation, and cell cycle arrest, and as such is a suboptimal biomarker of TMZ-induced drug action.


Effectiveness of Semantic Encoding Strategy Training after Traumatic Brain Injury is Correlated with Frontal Brain Activation Change.
Traumatic Brain Injury (TBI) is frequently associated with chronic, treatment-resistant memory problems, and is one of the leading causes of disability in otherwise healthy adults. Cognitive rehabilitation therapies are used with the goal of improving memory functioning; however, not all patients benefit. Prefrontal cortex (PFC) is critical for employing effective memory strategies. We hypothesized that memory improvement after a brief cognitive intervention would be associated with increases in PFC activation during a memory task. The current study used behavioral analyses and functional magnetic resonance imaging (fMRI) to examine the effects of two days of intensive semantic encoding strategy training on memory performance and brain activation patterns in patients in the post-acute stage of TBI. fMRI data were collected before and after training while participants learned word lists. Post-training vs. pre-training changes in total recall and semantic clustering during recall were positively correlated with post-training vs. pre-training changes in neural activation in PFC. These results suggest that variability in treatment response to cognitive training after TBI may be due in part to variability in PFC function, and that some survivors of TBIs may benefit from treatments specifically targeting the PFC.


Enhanced inhibition of microsomal cytochrome P450 3A2 in rat liver during diltiazem biotransformation.
Pharmacokinetic drug interactions involving the calcium channel blocker diltiazem (DTZ) have been attributed to inhibition of microsomal cytochrome P450 (P450)-mediated drug oxidation. Accumulation of certain DTZ metabolites during dosage with the drug, as well as dose-related differences in DTZ pharmacokinetics, suggests that DTZ metabolites may also participate in P450 inhibition. The present study evaluated a series of putative DTZ metabolites as inhibitors of major constitutive P450s in rat liver in vitro, in relation to DTZ biotransformation. The principal finding to emerge was that the N-demethylated metabolite of DTZ was a more potent competitive inhibitor than DTZ of CYP3A2-dependent testosterone 6 beta-hydroxylation. This P450 appeared to be the preferred target for inhibition, because the observed K/K(m) ratio for inhibition of CYP3A2-dependent steroid hydroxylation was approximately 4- and 100-fold lower than those for CYP2C11 and CYP2A1-dependent pathways, respectively. It was also established that N-desmethyl-DTZ was a major metabolite formed during microsomal DTZ biotransformation in rat liver in vitro. The other primary metabolites, desacetyl-DTZ and O-desmethyl-DTZ, were ineffective inhibitors of any pathways of steroid oxidation by P450s, but several other potential metabolites, which were not detected in microsomal incubations, also inhibited P450 activity. Consistent with previous reports, there was no evidence of P450 inactivation or complexation by DTZ, but the drug and its N-desmethyl metabolite generated binding interactions with ferric P450 in rat hepatic microsomes. Considered together, the findings of the present study establish that N-desmethyl-DTZ is a preferential inhibitor of CYP3A2 in rat hepatic microsomes, with greater potency than the parent drug. This is consistent with clinical reports in which this metabolite accumulates during multiple-dose therapy with DTZ. The competitive nature of the inhibitory interaction suggests that the eventual elimination of N-desmethyl-DTZ should restore normal hepatic oxidation capacity.


Advancing our knowledge of antigen processing with computational modelling, structural biology, and immunology.
Antigen processing is an immunological mechanism by which intracellular peptides are transported to the cell surface while bound to Major Histocompatibility Complex molecules, where they can be surveyed by circulating CD8+ or CD4+ T-cells, potentially triggering an immunological response. The antigen processing pathway is a complex multistage filter that refines a huge pool of potential peptide ligands derived from protein degradation into a smaller ensemble for surface presentation. Each stage presents unique challenges due to the number of ligands, the polymorphic nature of MHC and other protein constituents of the pathway and the nature of the interactions between them. Predicting the ensemble of displayed peptide antigens, as well as their immunogenicity, is critical for improving T cell vaccines against pathogens and cancer. Our predictive abilities have always been hindered by an incomplete empirical understanding of the antigen processing pathway. In this review, we highlight the role of computational and structural approaches in improving our understanding of antigen processing, including structural biology, computer simulation, and machine learning techniques, with a particular focus on the MHC-I pathway.


Harmonization and standardization of data for a pan-European cohort on SARS- CoV-2 pandemic.
The European project ORCHESTRA intends to create a new pan-European cohort to rapidly advance the knowledge of the effects and treatment of COVID-19. Establishing processes that facilitate the merging of heterogeneous clusters of retrospective data was an essential challenge. In addition, data from new ORCHESTRA prospective studies have to be compatible with earlier collected information to be efficiently combined. In this article, we describe how we utilized and contributed to existing standard terminologies to create consistent semantic representation of over 2500 COVID-19-related variables taken from three ORCHESTRA studies. The goal is to enable the semantic interoperability of data within the existing project studies and to create a common basis of standardized elements available for the design of new COVID-19 studies. We also identified 743 variables that were commonly used in two of the three prospective ORCHESTRA studies and can therefore be directly combined for analysis purposes. Additionally, we actively contributed to global interoperability by submitting new concept requests to the terminology Standards Development Organizations.


Astaxanthin prevents pulmonary fibrosis by promoting myofibroblast apoptosis dependent on Drp1-mediated mitochondrial fission.
Promotion of myofibroblast apoptosis is a potential therapeutic strategy for pulmonary fibrosis. This study investigated the antifibrotic effect of astaxanthin on the promotion of myofibroblast apoptosis based on dynamin-related protein-1 (Drp1)-mediated mitochondrial fission in vivo and in vitro. Results showed that astaxanthin can inhibit lung parenchymal distortion and collagen deposition, as well as promote myofibroblast apoptosis. Astaxanthin demonstrated pro-apoptotic function in myofibroblasts by contributing to mitochondrial fission, thereby leading to apoptosis by increasing the Drp1 expression and enhancing Drp1 translocation into the mitochondria. Two specific siRNAs were used to demonstrate that Drp1 is necessary to promote astaxanthin-induced mitochondrial fission and apoptosis in myofibroblasts. Drp1-associated genes, such as Bcl-2-associated X protein, cytochrome c, tumour suppressor gene p53 and p53-up-regulated modulator of apoptosis, were highly up-regulated in the astaxanthin group compared with those in the sham group. This study revealed that astaxanthin can prevent pulmonary fibrosis by promoting myofibroblast apoptosis through a Drp1-dependent molecular pathway. Furthermore, astaxanthin provides a potential therapeutic value in pulmonary fibrosis treatment.


Asymmetric Functional Connectivity of the Contra- and Ipsilateral Secondary Somatosensory Cortex during Tactile Object Recognition.
In the somatosensory system, it is well known that the bilateral secondary somatosensory cortex (SII) receives projections from the unilateral primary somatosensory cortex (SI), and the SII, in turn, sends feedback projections to SI. Most neuroimaging studies have clearly shown bilateral SII activation using only unilateral stimulation for both anatomical and functional connectivity across SII subregions. However, no study has unveiled differences in the functional connectivity of the contra- and ipsilateral SII network that relates to frontoparietal areas during tactile object recognition. Therefore, we used event-related functional magnetic resonance imaging (fMRI) and a delayed match-to-sample (DMS) task to investigate the contributions of bilateral SII during tactile object recognition. In the fMRI experiment, 14 healthy subjects were presented with tactile angle stimuli on their right index finger and asked to encode three sample stimuli during the encoding phase and one test stimulus during the recognition phase. Then, the subjects indicated whether the angle of test stimulus was presented during the encoding phase. The results showed that contralateral (left) SII activity was greater than ipsilateral (right) SII activity during the encoding phase, but there was no difference during the recognition phase. A subsequent psycho-physiological interaction (PPI) analysis revealed distinct connectivity from the contra- and ipsilateral SII to other regions. The left SII functionally connected to the left SI and right primary and premotor cortex, while the right SII functionally connected to the left posterior parietal cortex (PPC). Our findings suggest that in situations involving unilateral tactile object recognition, contra- and ipsilateral SII will induce an asymmetrical functional connectivity to other brain areas, which may occur by the hand contralateral effect of SII.


Sequence element enrichment analysis to determine the genetic basis of bacterial phenotypes.
Bacterial genomes vary extensively in terms of both gene content and gene sequence. This plasticity hampers the use of traditional SNP-based methods for identifying all genetic associations with phenotypic variation. Here we introduce a computationally scalable and widely applicable statistical method (SEER) for the identification of sequence elements that are significantly enriched in a phenotype of interest. SEER is applicable to tens of thousands of genomes by counting variable-length k-mers using a distributed string-mining algorithm. Robust options are provided for association analysis that also correct for the clonal population structure of bacteria. Using large collections of genomes of the major human pathogens Streptococcus pneumoniae and Streptococcus pyogenes, SEER identifies relevant previously characterized resistance determinants for several antibiotics and discovers potential novel factors related to the invasiveness of S. pyogenes. We thus demonstrate that our method can answer important biologically and medically relevant questions.


Dynamics of inert spheres in active suspensions of micro-rotors.
Inert particles suspended in active fluids of self-propelled particles are known to often exhibit enhanced diffusion and novel coherent structures. Here we numerically investigate the dynamical behavior and self-organization in a system consisting of passive and actively rotating spheres of the same size. The particles interact through direct collisions and the fluid flows generated as they move. In the absence of passive particles, three states emerge in a binary mixture of spinning spheres depending on particle fraction: a dilute gas-like state where the rotors move chaotically, a phase-separated state where like-rotors move in lanes or vortices, and a jammed state where crystals continuously assemble, melt and move (K. Yeo, E. Lushi, and P. M. Vlahovska, Phys. Rev. Lett., 2015, 114, 188301). Passive particles added to the rotor suspension modify the system dynamics and pattern formation: while states identified in the pure active suspension still emerge, they occur at different densities and mixture proportions. The dynamical behavior of the inert particles is also non-trivially dependent on the system composition.


Tracking epigenetic histone modifications in single cells using Fab-based live endogenous modification labeling.
Histone modifications play an important role in epigenetic gene regulation and genome integrity. It remains largely unknown, however, how these modifications dynamically change in individual cells. By using fluorescently labeled specific antigen binding fragments (Fabs), we have developed a general method to monitor the distribution and global level of endogenous histone H3 lysine modifications in living cells without disturbing cell growth and embryo development. Fabs produce distinct nuclear patterns that are characteristic of their target modifications. H3K27 trimethylation-specific Fabs, for example, are concentrated on inactive X chromosomes. As Fabs bind their targets transiently, the ratio of bound and free molecules depends on the target concentration, allowing us to measure changes in global modification levels. High-affinity Fabs are suitable for mouse embryo imaging, so we have used them to monitor H3K9 and H3K27 acetylation levels in mouse preimplantation embryos produced by in vitro fertilization and somatic cell nuclear transfer. The data suggest that a high level of H3K27 acetylation is important for normal embryo development. As Fab-based live endogenous modification labeling (FabLEM) is broadly useful for visualizing any modification, it should be a powerful tool for studying cell signaling and diagnosis in the future.


Association of two single nucleotide polymorphisms from genomewide association studies with clinical phenotypes of cerebral ischemia.
Recent genomewide association studies have revealed an association between two single nucleotide polymorphisms, rs11833579 and rs12425791, and ischemic stroke. To gain more insight in pathophysiological mechanisms underlying the found associations by exploring relationships between these single nucleotide polymorphisms and clinical and radiological characteristics of patients with cerebral ischemia. Our cohort consisted of 660 Caucasian patients with cerebral ischemia; from all patients detailed clinical and radiological data were available. Etiologic subtype of cerebral ischemia was determined according to the TOAST classification and an alternative classification. We studied associations between risk alleles and etiologic subtype, duration of ischemia, occurrence of multiple events, functional outcome and findings on CT-angiography by means of logistic regression analysis. The risk allele of rs11833579 was associated with an atherothrombotic etiology of cerebral ischemia, but not with other etiologic subtypes. Risk alleles of both single nucleotide polymorphisms were related to events of shorter duration (<24 h), the risk allele of rs11833579 with occurrence of multiple events. There was no association between single nucleotide polymorphism and clinical outcome. Both single nucleotide polymorphismswere associated with presence of stenotic calcifications and stenosis >30% in a symptomatic artery on CT-angiography. This is the first study to show an association of rs11833579 with multiple episodes of cerebral ischemia of atherothrombotic origin, and of rs11833579 and rs12425791 with short duration of ischemia. Also, we found an association of both single nucleotide polymorphisms with atherosclerotic lesions in the extracranial vessels on CT-angiography. Together this suggests a relationship between the two single nucleotide polymorphisms and large artery pathology.


Imaging of osteochondroma: variants and complications with radiologic-pathologic correlation.
Osteochondroma represents the most common bone tumor and is a developmental lesion rather than a true neoplasm. It constitutes 20%-50% of all benign bone tumors and 10%-15% of all bone tumors. Its radiologic features are often pathognomonic and identically reflect its pathologic appearance. Osteochondromas are composed of cortical and medullary bone with an overlying hyaline cartilage cap and must demonstrate continuity with the underlying parent bone cortex and medullary canal. Osteochondromas may be solitary or multiple, the latter being associated with the autosomal dominant syndrome, hereditary multiple exostoses (HME). Complications associated with osteochondromas are more frequent with HME and include deformity (cosmetic and osseous), fracture, vascular compromise, neurologic sequelae, overlying bursa formation, and malignant transformation. Malignant transformation is seen in 1% of solitary osteochondromas and in 3%-5% of patients with HME. Continued lesion growth and a hyaline cartilage cap greater than 1.5 cm in thickness, after skeletal maturity, suggest malignant transformation. Variants of osteochondroma include subungual exostosis, dysplasia epiphysealis hemimelica, turret and traction exostoses, bizarre parosteal osteochondromatous proliferation, and florid reactive periostitis. Recognition of the radiologic spectrum of appearances of osteochondroma and its variants usually allows prospective diagnosis and differentiation of the numerous potential complications, thus helping guide therapy and improving patient management.


Emergence of new PCR ribotypes from the hypervirulent Clostridium difficile 027 lineage.
Clostridium difficile is the most common cause of antibiotic-associated diarrhoea worldwide. Over the past 10 years, the incidence and severity of disease have increased in North America and Europe due to the emergence of a hypervirulent clone designated PCR ribotype 027. In this study, we sought to identify phenotypic differences among a collection of 26 presumed PCR ribotype 027 strains from the US and the UK isolated between 1988 and 2008 and also re-evaluated the PCR ribotype. We demonstrated that some of the strains typed as BI by restriction endonuclease analysis, and presumed to be PCR ribotype 027, were in fact other PCR ribotypes such as 176, 198 and 244 due to slight variation in banding pattern compared to the 027 strains. The reassigned 176, 198 and 244 ribotype strains were isolated in the US between 2001 and 2004 and appeared to have evolved recently from the 027 lineage. In addition, the UK strains were more motile and more resistant to most of the antibiotics compared to the US counterparts. We conclude that there should be a heightened awareness of newly identified PCR ribotypes such as 176, 198 and 244, and that they may be as problematic as the notorious 027 strains.


Glycan array analysis of Pholiota squarrosa lectin and other fucose-oriented lectins.
The α(1,6)fucose residue attached to the N-glycoprotein core is suspected to play an essential role in the progression of several types of cancer. Lectins remain the first choice for probing glycan modifications, although they may lack specificity. Thus, efforts have been made to identify new lectins with a narrower core fucose (CF) detection profile. Here, we present a comparison of the classical Aleuria aurantia lectin (AAL), Lens culinaris agglutinin (LCA) and Aspergillus oryzae lectin (AOL) with the newer Pholiota squarrosa lectin (PhoSL), which has been described as being specific for core fucosylated N-glycans. To this end, we studied the binding profiles of the four lectins using mammalian glycan arrays from the Consortium of Functional Glycomics. To validate their glycan specificity, we probed AOL, LCA and PhoSL in western-blot assays using protein extracts from eight common colorectal cancer (CRC) lines and colorectal biopsies from a small cohort of patients with CRC. The results showed that (i) LCA and PhoSL were the most specific lectins for detecting the presence of CF in a concentration-dependent manner; (ii) PhoSL exhibited the highest N-glycan sequence restriction, with preferential binding to core fucosylated paucimannosidic-type N-glycans, (iii) the recognition ability of PhoSL was highly influenced by the presence of terminal N-acetyl-lactosamine; (iv) LCA bound to paucimannosidic, bi-antennary and tri-antennary core fucosylated N-glycans and (v) AOL and AAL exhibited broader specificity towards fucosylation. Together, our results support the choice of LCA as the most appropriate lectin for CF detection, as validated in protein extracts from CRC cell lines and tissue specimens from patients with CRC.


Symptom-specific effects of cognitive-behavioral therapy, sertraline, and their combination in a large randomized controlled trial of pediatric anxiety disorders.
Pediatric anxiety disorders are highly prevalent and associated with significant functional disabilities and lifelong morbidity. Cognitive-behavioral therapy (CBT), sertraline, and their combination are effective treatments, but little is known about how these treatments exert their effects. Using network intervention analysis (NIA), we analyzed data from the largest randomized controlled treatment trial of pediatric anxiety disorders (Child/Adolescent Anxiety Multimodal Study, NCT00052078, clinicaltrials.gov/ct2/show/NCT00052078) and outlined the causal symptom domain-specific effects of CBT, sertraline, and their combination over the course of the 12-week treatment while taking into account both specificity and overlap between symptom domains. All active treatments produced positive effects with the most pronounced and consistent effects emerging in relation to psychological distress, family interference, and avoidance. Psychological distress was consistently the most and physical symptoms the least central symptom domain in the disorder network. All active treatments showed beneficial effects when compared to placebo, and NIA identified that these effects were exerted similarly across treatments and primarily through a reduction of psychological distress, family interference, and avoidance. CBT and sertraline may have differential mechanisms of action in relation to psychological distress. Given the lack of causal effects on interference outside family and physical symptoms, interventions tailored to target these domains may aid in the building of more effective treatments. Psychological distress and avoidance should remain key treatment focuses because of their central roles in the disorder network. The findings inform and promote developing more effective interventions.


UV absorption of Criegee intermediates: quantitative cross sections from high-level ab initio theory.
Criegee intermediates (CIs) are increasingly recognized as important intermediates in atmospheric and combustion chemistry. Modelling in these fields requires reliable characterization of the CI's UV absorption cross sections. Different experimental approaches provided seemingly contradictory results both for the simplest CI as well as for higher analogues. To resolve these discrepancies, we model simultaneously the positions, widths, shapes and absolute intensities of the first absorption bands of CIs using the semiclassical reflection principle approach based on the path integral molecular dynamics. The UV spectra were efficiently processed via the kernel density estimation method. We show that the multireference character complicates the description of the system and the appropriate treatment of the electron correlation is vital. Multi-reference methods with dynamical correlation are problematic due to high sensitivity of the results with respect to the active space. Single-reference based methods become reliable once the triple excitations components are included. Interestingly, the very similar CC2 and ADC(2) methods provide highly conflicting results which are, however, reconciled at the CC3 and ADC(3) levels. To calculate the spectra of higher CIs, we introduce composite EOM-CCSD/T and CC2/3 methods providing excellent absorption cross sections at an acceptable computational cost. We provide the first absolute intensities for individual conformers of the CH3CHOO molecule.


Spatial Variation in the Quality of American Community Survey Estimates.
Social science research, public and private sector decisions, and allocations of federal resources often rely on data from the American Community Survey (ACS). However, this critical data source has high uncertainty in some of its most frequently used estimates. Using 2006-2010 ACS median household income estimates at the census tract scale as a test case, we explore spatial and nonspatial patterns in ACS estimate quality. We find that spatial patterns of uncertainty in the northern United States differ from those in the southern United States, and they are also different in suburbs than in urban cores. In both cases, uncertainty is lower in the former than the latter. In addition, uncertainty is higher in areas with lower incomes. We use a series of multivariate spatial regression models to describe the patterns of association between uncertainty in estimates and economic, demographic, and geographic factors, controlling for the number of responses. We find that these demographic and geographic patterns in estimate quality persist even after we account for the number of responses. Our results indicate that data quality varies across places, making cross-sectional analysis both within and across regions less reliable. Finally, we present advice for data users and potential solutions to the challenges identified.


Regression of atherosclerosis in apolipoprotein E-deficient mice is feasible using high-dose angiotensin receptor blocker, candesartan.
Clinical studies have suggested that renin-angiotensin inhibitors are effective for the prevention of atherosclerosis progression, but the results for the regression of established lesions are equivocal. The aim of this study was to examine the effects of different doses of the angiotensin receptor blocker (ARB) candesartan on the regression of atherosclerosis and lipid-induced nephropathy in apolipoprotein E (apoE)-deficient spontaneously hyperlipidemic (SHL) mice. Male SHL were given an atherogenic diet together with salt loading to induce atherosclerosis. The mice were then treated with various doses of candesartan (0-50 mg/kg/d) for 12 weeks. Treatment with high-dose candesartan caused clear regression of atherosclerotic plaques in the aorta, which was not observed with normal-dose candesartan. Biglycan and ACAT1 expression were significantly decreased, and aortic free cholesterol: cholesterol ester ratios were increased in these mice. Treatment of cultured THP-1 macrophages in vitro with candesartan resulted in a similar decrease in ACAT1 expression. In the kidney, glomerular lipid accumulation, mesangial expansion, and albuminuria were significantly regressed after treatment with high-dose candesartan, while biglycan and ACAT1 expressions were decreased. These results suggest that regression of established atherosclerosis lesions in ApoE-deficient mice is feasible using high-dose candesartan, by mechanisms involving (i) a decrease in the lipid-retaining proteoglycan biglycan, and (ii) suppression of ACAT1 expression resulting in increased free cholesterol for lipid release.


A novel fluorescence-activated cell sorter-based screen for yeast endocytosis mutants identifies a yeast homologue of mammalian eps15.
A complete understanding of the molecular mechanisms of endocytosis requires the discovery and characterization of the protein machinery that mediates this aspect of membrane trafficking. A novel genetic screen was used to identify yeast mutants defective in internalization of bulk lipid. The fluorescent lipophilic styryl dye FM4-64 was used in conjunction with FACS to enrich for yeast mutants that exhibit internalization defects. Detailed characterization of two of these mutants, dim1-1 and dim2-1, revealed defects in the endocytic pathway. Like other yeast endocytosis mutants, the temperature-sensitive dim mutant were unable to endocytose FM4-64 or radiolabeled alpha-factor as efficiently as wild-type cells. In addition, double mutants with either dim1-delta or dim2-1 and the endocytosis mutants end4-1 or act1-1 displayed synthetic growth defects, indicating that the DIM gene products function in a common or parallel endocytic pathway. Complementation cloning of the DIM genes revealed identity of DIM1 to SHE4 and DIM2 to PAN1. Pan1p shares homology with the mammalian clathrin adaptor-associated protein, eps15. Both proteins contain multiple EH (eps15 homology) domains, a motif proposed to mediate protein-protein interactions. Phalloidin labeling of filamentous actin revealed profound defects in the actin cytoskeleton in both dim mutants. EM analysis revealed that the dim mutants accumulate vesicles and tubulo-vesicular structures reminiscent of mammalian early endosomes. In addition, the accumulation of novel plasma membrane invaginations where endocytosis is likely to occur were visualized in the mutants by electron microscopy using cationized ferritin as a marker for the endocytic pathway. This new screening strategy demonstrates a role for She4p and Pan1p in endocytosis, and provides a new general method for the identification of additional endocytosis mutants.


The impact of prostate volume, number of biopsy cores and American Urological Association symptom score on the sensitivity of cancer detection using the Prostate Cancer Prevention Trial risk calculator.
We assessed the independent predictive value of prostate volume, number of biopsy cores and AUASS (American Urological Association symptom score) compared to risk factors included in the PCPTRC (Prostate Cancer Prevention Trial risk calculator for prostate cancer) and PCPTHG (Prostate Cancer Prevention Trial risk calculator for high grade cancer [Gleason grade 7 or greater]). Of 5,519 PCPT (Prostate Cancer Prevention Trial) participants used to construct the PCPTRC 4,958 with AUASS and prostate specific antigen 10 ng/ml or less were included on logistic regression analysis. Risk algorithms were evaluated in 571 EDRN (Early Detection Research Network) participants using the ROC AUC. A total of 1,094 participants (22.1%) had prostate cancer, of whom 232 (21.2%) had high grade disease. For prostate cancer prediction higher prostate specific antigen, abnormal digital rectal examination, family history of prostate cancer and number of cores were associated with increased risk, while volume was associated with decreased risk. Excluding prostate volume and number of cores, a history of negative biopsy and increased AUASS were also associated with lower risk. For high grade cancer higher prostate specific antigen, abnormal digital rectal examination, black race and number of cores were associated with increased risk and volume, while AUASS was associated with decreased risk. The AUC of the PCPTRC adjusted for volume and number of cores was 72.7% (using EDRN data), 68.2% when adjusted for AUASS alone and 67.6% PCPTRC. For high grade disease the AUCs were 74.8%, 74.0% and 73.5% (PCPTHG), respectively. Adjusted PCPT risk calculators for volume, number of cores and AUASS improve cancer detection.


Genetic clues to glaucoma's secrets. The L Edward Jackson Memorial Lecture. Part 2.
Major advances in the medical and surgical treatment of glaucoma have occurred since the first Edward Jackson Memorial lecture was delivered 50 years ago. Collaborative clinical trials under the sponsorship of the National Eye Institute are adding to our knowledge about which patients to treat and how to treat them. Despite these clinical advances, an understanding of the pathophysiologic and biochemical mechanisms that cause the disease remain unknown. The 40th anniversary of the discovery of the DNA double helix provides a springboard for a historical perspective on the heritability of glaucoma. A large pedigree is presented of a family with autosomal dominantly inherited primary open-angle glaucoma of juvenile onset. This is the second family with this clinical entity to show genetic linkage to the long arm of chromosome 1. Other forms of primary open-angle glaucoma with adult onset are presented wherein the inheritance pattern suggests autosomal recessive transmission. Thus far, linkage analysis does not suggest a genetic relationship to the autosomal dominant juvenile-onset pedigree that links to the long arm of chromosome 1. It is hoped that an emphasis on clinical and molecular genetic studies of glaucoma will yield protein defects that can be targeted for treatment. It is emphasized that the clinical ophthalmologist can participate in this important work by finding families with glaucoma and collaborating with individuals capable of extracting DNA, manipulating it, and performing genetic linkage and positional cloning studies.


Harnessing the potential of adult cardiac stem cells: lessons from haematopoiesis, the embryo and the niche.
Across biomedicine, there is a major drive to develop stem cell (SC) treatments for debilitating diseases. Most effective treatments restore an embryonic phenotype to adult SCs. This has led to two emerging paradigms in SC biology: the application of developmental biology studies and the manipulation of the SC niche. Developmental studies can reveal how SCs are orchestrated to build organs, the understanding of which is important in order to instigate tissue repair in the adult. SC niche studies can reveal cues that maintain SC 'stemness' and how SCs may be released from the constraints of the niche to differentiate and repopulate a 'failing' organ. The haematopoietic system provides an exemplar whereby characterisation of the blood lineages during development and the bone marrow niche has resulted in therapeutics now routinely used in the clinic. Ischaemic heart disease is a major cause of morbidity and mortality in humans and the question remains as to whether these principles can be applied to the heart, in order to exploit the potential of adult SCs for use in cardiovascular repair and regeneration.


A dynamic model of the hypoxia-inducible factor 1α (HIF-1α) network.
Activation of the hypoxia-inducible factor (HIF) pathway is a critical step in the transcriptional response to hypoxia. Although many of the key proteins involved have been characterised, the dynamics of their interactions in generating this response remain unclear. In the present study, we have generated a comprehensive mathematical model of the HIF-1α pathway based on core validated components and dynamic experimental data, and confirm the previously described connections within the predicted network topology. Our model confirms previous work demonstrating that the steps leading to optimal HIF-1α transcriptional activity require sequential inhibition of both prolyl- and asparaginyl-hydroxylases. We predict from our model (and confirm experimentally) that there is residual activity of the asparaginyl-hydroxylase FIH (factor inhibiting HIF) at low oxygen tension. Furthermore, silencing FIH under conditions where prolyl-hydroxylases are inhibited results in increased HIF-1α transcriptional activity, but paradoxically decreases HIF-1α stability. Using a core module of the HIF network and mathematical proof supported by experimental data, we propose that asparaginyl hydroxylation confers a degree of resistance upon HIF-1α to proteosomal degradation. Thus, through in vitro experimental data and in silico predictions, we provide a comprehensive model of the dynamic regulation of HIF-1α transcriptional activity by hydroxylases and use its predictive and adaptive properties to explain counter-intuitive biological observations.


Current and former marijuana use: preliminary findings of a longitudinal study of effects on IQ in young adults.
Assessing marijuana's impact on intelligence quotient (IQ) has been hampered by a lack of evaluation of subjects before they begin to use this substance. Using data from a group of young people whom we have been following since birth, we examined IQ scores before, during and after cessation of regular marijuana use to determine any impact of the drug on this measure of cognitive function. We determined marijuana use for seventy 17- to 20-year-olds through self-reporting and urinalysis. IQ difference scores were calculated by subtracting each person's IQ score at 9-12 years (before initiation of drug use) from his or her score at 17-20 years. We then compared the difference in IQ scores of current heavy users (at least 5 joints per week), current light users (less than 5 joints per week), former users (who had not smoked regularly for at least 3 months) and non-users (who never smoked more than once per week and no smoking in the past two weeks). Current marijuana use was significantly correlated (p < 0.05) in a dose-related fashion with a decline in IQ over the ages studied. The comparison of the IQ difference scores showed an average decrease of 4.1 points in current heavy users (p < 0.05) compared to gains in IQ points for light current users (5.8), former users (3.5) and non-users (2.6). Current marijuana use had a negative effect on global IQ score only in subjects who smoked 5 or more joints per week. A negative effect was not observed among subjects who had previously been heavy users but were no longer using the substance. We conclude that marijuana does not have a long-term negative impact on global intelligence. Whether the absence of a residual marijuana effect would also be evident in more specific cognitive domains such as memory and attention remains to be ascertained.


Uncovering the enzymes that catalyze the final steps in oxytetracycline biosynthesis.
Tetracyclines are a group of natural products sharing a linearly fused four-ring scaffold, which is essential for their broad-spectrum antibiotic activities. Formation of the key precursor anhydrotetracycline 3 during oxytetracycline 1 biosynthesis has been previously characterized. However, the enzymatic steps that transform 3 into 1, including the additional hydroxylation at C5 and the final C5a-C11a reduction, have remained elusive. Here we report two redox enzymes, OxyS and OxyR, are sufficient to convert 3 to 1. OxyS catalyzes two sequential hydroxylations at C6 and C5 positions of 3 with opposite stereochemistry, while OxyR catalyzes the C5a-C11a reduction using F420 as a cofactor to produce 1. The crystal structure of OxyS was obtained to provide insights into the tandem C6- and C5-hydroxylation steps. The substrate specificities of OxyS and OxyR were shown to influence the relative ratio of 1 and tetracycline 2.


Modeling epigenetic regulation of PRC1 protein accumulation in the cell cycle.
Epigenetic regulation contributes to many important processes in biological cells. Examples include developmental processes, differentiation and maturation of stem cells, evolution of malignancy and other. Cell cycle regulation has been subject of mathematical modeling by a number of authors that resulted in many interesting models and application of analytic techniques ranging from stochastic processes to partial differential equations and to integral, functional and operator equations. In this paper we address the question of how the regulation of protein contents influences the long-term dynamics of the population. To accomplish this, we follow the philosophy of a 1984 model by Kimmel et al., but adjust the details to fit the experimental data on protein PRC1 from a more recent paper. We built a model of cell cycle dynamics of the PRC1 and fitted it to the data made available by Cohen and his co-authors. We have run the model for a large number of cell generations, recording the PRC1 contents in all cells of the resulting pedigree, at constant time intervals. During cell division the PRC1 is unequally divided between daughter cells. The picture emerging from simulations of Data set 1 is that of a very well-tuned regulatory circuit that provides a stable distribution of PRC1 contents and interdivision times. Data set 2 seems qualitatively different, with more variation in cell cycle duration. The main question we address is whether the regulatory feedbacks deduced from single cell cycle data provide epigenetic regulation of cell characteristics in long run. PRC1 is a good candidate because of its role in setting timing of division. Findings of the current paper include tight regulation of the cell cycle (particularly the timing of the cell cycle) even that PRC1 is only one of the players in cell dynamics. Understanding that association, even close, does not necessarily imply causation, we consider this an interesting and important result.


Topical exposure to exogenous ultraviolet-irradiated urocanic acid enhances Mycobacterium ulcerans infection in a Crl:IAF(HA)-hrBR hairless guinea-pig model of Buruli ulcer disease.
Ultraviolet radiation (UVR) pre-exposure enhances Mycobacterium ulcerans infection in the Crl:IAF(HA)-hrBR hairless guinea-pig, possibly via a photoimmunosuppressive mechanism. The trans-cis photoisomerization of epidermal urocanic acid is an important initiator of the web of events leading to photoimmunosuppression. Thus, the hypothesis tested in this paper was that topical pre-exposure to UVR-irradiated urocanic acid mixture containing cis-urocanic acid (UVR-UCA) enhances the ulcerative form of M. ulcerans infection in the Crl:IAF(HA)-hrBR hairless guinea-pig model of human Buruli ulcer disease. Groups of six animals were subjected to daily topical treatment with either 0 (vehicle only), 0.1, 0.5 or 1 mg of trans (tUCA) or UVR-UCA (contained a cis : trans urocanic acid isomer ratio of 1 : 9) for three consecutive days. A sham treatment group was also included in the experiment. Three days following their final treatment, the guinea-pigs were intradermally infected in the right dorsal flank with 1.5 x 107 CFU of M. ulcerans in 0.1 ml of phosphate-buffered saline (PBS) and sham infected with 0.1 ml of PBS in the left dorsal flank. The resultant skin lesions were then measured over the next 21 days. At day 21 postinfection, the animals were tested for delayed-type hypersensitivity (DTH) reactivity to M. ulcerans cell fragment antigens (MCF). Distinct, well-demarcated, dermally situated skin nodules were present at infected, but not sham-infected, skin sites by day 3 postinfection, and the lesions progressed to frank ulcers by day 5. Between days 5 and 21, the mean lesion diameters of the UVR-UCA-treated animals were significantly (P<0.001) greater than those of the sham, vehicle only or tUCA-treated groups. UVR-UCA-treated guinea-pigs also had significantly (P<0.001) suppressed DTH responses to MCF compared with the other treatment groups. There were no significant (P>0.4) differences between the lesion sizes and DTH responses of the tUCA, vehicle only or sham treatment groups. These results demonstrate that topical exposure to UVR-UCA promotes M. ulcerans infection and suppresses DTH responses to M. uclerans antigens in infected animals. These results lend credence to the hypothesis that UVR-mediated enhancement of Buruli ulcer disease in the Crl:IAF(HA)-hrBR hairless guinea-pig model occurs via modulation of cis-urocanic acid-susceptible immune pathways.


Strategic deployment of feature-based attentional gain in primate visual cortex.
Attending to visual stimuli enhances the gain of those neurons in primate visual cortex that preferentially respond to the matching locations and features (on-target gain). Although this is well suited to enhance the neuronal representation of attended stimuli, it is nonoptimal under difficult discrimination conditions, as in the presence of similar distractors. In such cases, directing attention to neighboring neuronal populations (off-target gain) has been shown to be the most efficient strategy, but although such a strategic deployment of attention has been shown behaviorally, its underlying neural mechanisms are unknown. Here, we investigated how attention affects the population responses of neurons in the middle temporal (MT) visual area of rhesus monkeys to bidirectional movement inside the neurons' receptive field (RF). The monkeys were trained to focus their attention onto the fixation spot or to detect a direction or speed change in one of the motion directions (the "target"), ignoring the distractor motion. Population activity profiles were determined by systematically varying the patterns' directions while maintaining a constant angle between them. As expected, the response profiles show a peak for each of the 2 motion directions. Switching spatial attention from the fixation spot into the RF enhanced the peak representing the attended stimulus and suppressed the distractor representation. Importantly, the population data show a direction-dependent attentional modulation that does not peak at the target feature but rather along the slopes of the activity profile representing the target direction. Our results show that attentional gains are strategically deployed to optimize the discriminability of target stimuli, in line with an optimal gain mechanism proposed by Navalpakkam and Itti.


Single-step enrichment by Ti4+-IMAC and label-free quantitation enables in-depth monitoring of phosphorylation dynamics with high reproducibility and temporal resolution.
Quantitative phosphoproteomics workflows traditionally involve additional sample labeling and fractionation steps for accurate and in-depth analysis. Here we report a high-throughput, straightforward, and comprehensive label-free phosphoproteomics approach using the highly selective, reproducible, and sensitive Ti(4+)-IMAC phosphopeptide enrichment method. We demonstrate the applicability of this approach by monitoring the phosphoproteome dynamics of Jurkat T cells stimulated by prostaglandin E2 (PGE2) over six different time points, measuring in total 108 snapshots of the phosphoproteome. In total, we quantitatively monitored 12,799 unique phosphosites over all time points with very high quantitative reproducibility (average r > 0.9 over 100 measurements and a median cv < 0.2). PGE2 is known to increase cellular cAMP levels, thereby activating PKA. The in-depth analysis revealed temporal regulation of a wide variety of phosphosites associated not only with PKA, but also with a variety of other classes of kinases. Following PGE2 stimulation, several pathways became only transiently activated, revealing that in-depth dynamic profiling requires techniques with high temporal resolution. Moreover, the large publicly available dataset provides a valuable resource for downstream PGE2 signaling dynamics in T cells, and cAMP-mediated signaling in particular. More generally, our method enables in-depth, quantitative, high-throughput phosphoproteome screening on any system, requiring very little sample, sample preparation, and analysis time.


Bifidobacterium bifidum Extracellular Sialidase Enhances Adhesion to the Mucosal Surface and Supports Carbohydrate Assimilation.
Bifidobacterium is a natural inhabitant of the human gastrointestinal (GI) tract. We studied the role of the extracellular sialidase (SiaBb2, 835 amino acids [aa]) from Bifidobacterium bifidum ATCC 15696 in mucosal surface adhesion and carbohydrate catabolism. Human milk oligosaccharides (HMOs) or porcine mucin oligosaccharides as the sole carbon source enhanced B. bifidum growth. This was impaired in a B. bifidum ATCC 15696 strain harboring a mutation in the siabb2 gene. Mutant cells in early to late exponential growth phase also showed decreased adhesion to human epithelial cells and porcine mucin relative to the wild-type strain. These results indicate that SiaBb2 removes sialic acid from HMOs and mucin for metabolic purposes and may promote bifidobacterial adhesion to the mucosal surface. To further characterize SiaBb2-mediated bacterial adhesion, we examined the binding of His-tagged recombinant SiaBb2 peptide to colonic mucins and found that His-SiaBb2 as well as a conserved sialidase domain peptide (aa 187 to 553, His-Sia) bound to porcine mucin and murine colonic sections. A glycoarray assay revealed that His-Sia bound to the α2,6-linked but not to the α2,3-linked sialic acid on sialyloligosaccharide and blood type A antigen [GalNAcα1-3(Fucα1-2)Galβ] at the nonreducing termini of sugar chains. These results suggest that the sialidase domain of SiaBb2 is responsible for this interaction and that the protein recognizes two distinct carbohydrate structures. Thus, SiaBb2 may be involved in Bifidobacterium-mucosal surface interactions as well as in the assimilation of a variety of sialylated carbohydrates.IMPORTANCE Adhesion to the host mucosal surface and carbohydrate assimilation are important for bifidobacterium colonization and survival in the host gastrointestinal tract. In this study, we investigated the mechanistic basis for B. bifidum extracellular sialidase (SiaBb2)-mediated adhesion. SiaBb2 cleaved sialyl-human milk oligosaccharides and mucin glycans to produce oligosaccharides that supported B. bifidum growth. Moreover, SiaBb2 enhanced B. bifidum adhesion to mucosal surfaces via specific interactions with the α2,6 linkage of sialyloligosaccharide and blood type A antigen on mucin carbohydrates. These findings provide insight into the bifunctional role of SiaBb2 and the adhesion properties of B. bifidum strains.


Are the days of counting seizures numbered?
The estimation of seizure frequency is a cornerstone of clinical management of epilepsy and the evaluation of new therapies. Current estimation approaches are significantly limited by several factors. Comparing patient diaries and objective estimates (through both inpatient video-EEG monitoring of and long-term ambulatory EEG studies) reveal that patients document seizures inaccurately. So far, few practical alternative methods of estimation have been available. We review the systems of counting currently utilized and their limitations, as well as the limitations imposed by problems defining clinical events. Alternative methodologies that permit the volatility of seizure rates to be accommodated, and possible alternative measures of brain excitability will be outlined. Recent developments in technologies around data capture, such as wearable and implantable devices, as well as significant advances in the ability to analyse the large data-sets supplied by these systems have provided a wealth of information. There are now unprecedented opportunities to utilize and apply these insights in routine clinical management and assessment of therapies. The rapid adoption of long-term, wearable monitoring systems will permit major advances in our understanding of the natural history of epilepsy, and lead to more effective therapies and improved patient safety.


Determining the recommended dose of pacritinib: results from the PAC203 dose-finding trial in advanced myelofibrosis.
PAC203 is a randomized dose-finding study of pacritinib, an oral JAK2/IRAK1 inhibitor, in patients with advanced myelofibrosis who are intolerant of or resistant to ruxolitinib. Patients were randomized 1:1:1 to pacritinib 100 mg once per day, 100 mg twice per day, or 200 mg twice per day. Enhanced eligibility criteria, monitoring, and dose modifications were implemented to mitigate risk of cardiac and hemorrhagic events. Efficacy was based on ≥35% spleen volume response (SVR) and ≥50% reduction in the 7-component total symptom score (TSS) through week 24. Of 161 patients, 73% were intolerant of and 76% had become resistant to ruxolitinib; 50% met criteria for both. Severe thrombocytopenia (platelet count <50 × 103/μL) was present in 44%. SVR rates were highest with 200 mg twice per day (100 mg once per day, 0%; 100 mg twice per day, 1.8%; 200 mg twice per day, 9.3%), particularly among patients with baseline platelet counts <50 × 103/μL (17%; 4 of 24). Although TSS response rate was similar across doses (100 mg once per day, 7.7%; 100 mg twice per day, 7.3%; 200 mg twice per day, 7.4%), median percent reduction in TSS suggested a dose-response relationship (-3%, -16%, and -27%, respectively). Pharmacokinetic and pharmacodynamic modeling based on all available data showed greatest SVR and TSS reduction at 200 mg twice per day compared with lower doses. Common adverse events were gastrointestinal events, thrombocytopenia, and anemia. There was no excess of grade ≥3 hemorrhagic or cardiac events at 200 mg twice per day. Pacritinib 200 mg twice per day demonstrated clinical activity and an acceptable safety profile and was selected as the recommended dose for a pivotal phase 3 study in patients with myelofibrosis and severe thrombocytopenia. This trial was registered at www.clinicaltrials.gov as #NCT03165734.


Does a methionine-to-norleucine substitution in PGLa influence peptide-membrane interactions?
Yes. To understand the molecular mechanisms of amphiphilic membrane-active peptides, it is essential to study their interactions with lipid bilayers under near-native conditions. Amino acid composition largely determines the non-specific properties of peptides, on the basis of the physicochemical properties of the side chains. The resultant effects on peptides' functional properties include influences on the conformation, structural dynamics and binding affinities within the peptide interactome. Here, we studied the effect of substituting oxidation-prone methionine (Met) with non-oxidizable norleucine (Nle) in the model α-helical antimicrobial peptide PGLa, through systematic comparison of PGLa with the (2)Met/(2)Nle mutant. Both peptides were evaluated for their bacteriostatic and hemolytic activities (using in situ assays), for their conformational preferences in isotropic solutions (using circular dichroism spectropolarimetry) and for their abilities to modulate membrane curvature (using a solid-state (31)P NMR assay). We determined the membrane-bound states in detail and characterized the orientational dynamics of both peptides in oriented phospholipid membranes by solid-state (19)F NMR spectroscopy. On the one hand, the bioactivity results, the structure in the diluted membrane-mimicking environments and the strong inhibition of the negative membrane curvature were comparable between PGLa and the mutant. On the other hand, the alignments in DMPC bilayer were qualitatively the same but differed in absolute values - the more hydrophobic Nle residue inserted deeper in the membrane core. Furthermore, the mutant peptide displayed a significantly reduced ability to re-orient from the monomeric, surficial to the putative dimeric, tilted state. Overall, these results confirm the functional isosterism of Nle and Met in the helical membrane-active peptides but highlight differences in the ways in which the two residues affect non-specific binding to the lipid bilayer and homomeric peptide-peptide interactions.


Prophylactic biological mesh reinforcement versus standard closure of stoma site (ROCSS): a multicentre, randomised controlled trial.
Closure of an abdominal stoma, a common elective operation, is associated with frequent complications; one of the commonest and impactful is incisional hernia formation. We aimed to investigate whether biological mesh (collagen tissue matrix) can safely reduce the incidence of incisional hernias at the stoma closure site. In this randomised controlled trial (ROCSS) done in 37 hospitals across three European countries (35 UK, one Denmark, one Netherlands), patients aged 18 years or older undergoing elective ileostomy or colostomy closure were randomly assigned using a computer-based algorithm in a 1:1 ratio to either biological mesh reinforcement or closure with sutures alone (control). Training in the novel technique was standardised across hospitals. Patients and outcome assessors were masked to treatment allocation. The primary outcome measure was occurrence of clinically detectable hernia 2 years after randomisation (intention to treat). A sample size of 790 patients was required to identify a 40% reduction (25% to 15%), with 90% power (15% drop-out rate). This study is registered with ClinicalTrials.gov, NCT02238964. Between Nov 28, 2012, and Nov 11, 2015, of 1286 screened patients, 790 were randomly assigned. 394 (50%) patients were randomly assigned to mesh closure and 396 (50%) to standard closure. In the mesh group, 373 (95%) of 394 patients successfully received mesh and in the control group, three patients received mesh. The clinically detectable hernia rate, the primary outcome, at 2 years was 12% (39 of 323) in the mesh group and 20% (64 of 327) in the control group (adjusted relative risk [RR] 0·62, 95% CI 0·43-0·90; p=0·012). In 455 patients for whom 1 year postoperative CT scans were available, there was a lower radiologically defined hernia rate in mesh versus control groups (20 [9%] of 229 vs 47 [21%] of 226, adjusted RR 0·42, 95% CI 0·26-0·69; p<0·001). There was also a reduction in symptomatic hernia (16%, 52 of 329 vs 19%, 64 of 331; adjusted relative risk 0·83, 0·60-1·16; p=0·29) and surgical reintervention (12%, 42 of 344 vs 16%, 54 of 346: adjusted relative risk 0·78, 0·54-1·13; p=0·19) at 2 years, but this result did not reach statistical significance. No significant differences were seen in wound infection rate, seroma rate, quality of life, pain scores, or serious adverse events. Reinforcement of the abdominal wall with a biological mesh at the time of stoma closure reduced clinically detectable incisional hernia within 24 months of surgery and with an acceptable safety profile. The results of this study support the use of biological mesh in stoma closure site reinforcement to reduce the early formation of incisional hernias. National Institute for Health Research Research for Patient Benefit and Allergan.


Circulating proteins as predictors of incident heart failure in the elderly.
To identify novel risk markers for incident heart failure using proteomic profiling of 80 proteins previously associated with cardiovascular pathology. Proteomic profiling (proximity extension assay) was performed in two community-based prospective cohorts of elderly individuals without heart failure at baseline: the Prospective Investigation of the Vasculature in Uppsala Seniors [PIVUS, n = 901, median age 70.2 (interquartile range 70.0-70.3) years, 80 events]; and the Uppsala Longitudinal Study of Adult Men [ULSAM, n = 685, median age 77.8 (interquartile range 76.9-78.1) years, 90 events]. Twenty-nine proteins were associated with incident heart failure in the discovery cohort PIVUS after adjustment for age and sex, and correction for multiple testing. Eighteen associations replicated in ULSAM. In pooled analysis of both cohorts, higher levels of nine proteins were associated with incident heart failure after adjustment for established risk factors: growth differentiation factor 15 (GDF-15), T-cell immunoglobulin and mucin domain 1 (TIM-1), tumour necrosis factor-related apoptosis-inducing ligand receptor 2 (TRAIL-R2), spondin-1 (SPON1), matrix metalloproteinase-12 (MMP-12), follistatin (FS), urokinase-type plasminogen activator surface receptor (U-PAR), osteoprotegerin (OPG), and suppression of tumorigenicity 2 (ST2). Of these, GDF-15, U-PAR, MMP-12, TRAIL-R2, SPON1 and FS were associated with worsened echocardiographic left ventricular systolic function at baseline, while only TIM-1 was positively associated with worsened diastolic function (P < 0.02 for all). Proteomic profiling identified several novel associations between proteins involved in apoptosis, inflammation, matrix remodelling, and fibrinolysis with incident heart failure in elderly individuals. Our results encourage additional studies investigating the underlying mechanisms and the clinical utility of our findings.


Determinants of Child Attachment in the Years Postpartum in a High-Risk Sample of Immigrant Women.
Our goal was to examine maternal mental health and associated stresses in a sample of high-risk immigrant mothers, and its association with child insecure attachment in the years following childbirth. Mothers and their child (Mage = 37 months) were recruited through a Health and Social Service organization in the Parc-Extension neighborhood in Montreal, Quebec. Mothers completed the Hopkins Symptoms Checklist (HSCL-25), the Multidimensional Scale of Perceived Social Support (MPSS) and a sociodemographic questionnaire that included questions on premature delivery and birth weight. Attachment behaviors were coded out of a videotaped free play sequence using the Preschool and Early School-Age Attachment Rating Scales (PARS). Analysis revealed high levels of clinical anxiety and depression, low social support and low attachment security. Significant mean differences and associations were found between anxiety, depression, social support, preterm delivery and child attachment. These results underscore the importance of screening for anxiety and depression early in the postnatal years, in order to prevent associated consequences such as child insecure attachment. Results also highlight the importance of building positive social networks, especially with immigrant populations.


Unclassified Vasculitis with Episcleritis, Thrombophlebitis, Deep Vein Thrombosis, Pulmonary Vasculitis, and Intracranial Vasculitis: An Autopsy Case Report.
BACKGROUND Systemic vasculitides constitute heterogenous conditions affecting many organs and systems through blood vessel inflammation. Although there are some classifications for vasculitis, several vasculitides are "unclassified" because they cannot be clearly assigned to one of the known entities. CASE REPORT We report an autopsy case of a 67-year-old Japanese man who presented with fever, ocular pain, erythema, chest pain, and headache. The disease caused episcleritis, thrombophlebitis, extensive deep vein thrombosis, multiple pulmonary nodules and masses, hypertrophic pachymeningitis, and hyper-intensity areas in brain parenchyma on magnetic resonance images. Histopathology of the pulmonary nodule confirmed vasculitis affecting medium-to-small veins and arteries without necrotizing vasculitis or granulomatous inflammation. We diagnosed the patient with unclassified vasculitis based on the clinicopathological characteristics. Steroids in combination with immunosuppressants were used, but the disease was refractory and relapsing. The disease activity was eventually controlled with rituximab, but the patient died of bronchopneumonia. On autopsy, lung and brain findings indicated healed vascular inflammation. CONCLUSIONS This is the first case report of unclassified vasculitis, which is characterized as medium-to-small-sized arteritis and phlebitis, causing episcleritis, thrombophlebitis, deep vein thrombosis, pulmonary vasculitis, and intracranial vasculitis. The clinical conditions share some similarities with granulomatosis with polyangiitis and Behçet's disease; however, they meet no classification criteria of any specific vasculitis. More cases need to be analyzed to confirm our findings.


Deficient behavioral inhibition and anomalous selective attention in a community sample of adolescents with psychopathic traits and low-anxiety traits.
Socialization is the important process by which individuals learn and then effectively apply the rules of appropriate societal behavior. Response modulation is a psychobiological process theorized to aid in socialization by allowing individuals to utilize contextual information to modify ongoing behavior appropriately. Using Hare's (1991) Psychopathy Checklist and the Welsh (1956) anxiety scale, researchers have identified a relatively specific form of a response modulation deficit in low-anxious, Caucasian psychopaths. Preliminary evidence suggests that the Antisocial Process Screening Device (APSD; Frick & Hare, 2001) may be used to identify children with a similar vulnerability. Using a representative community sample of 308 16-year-olds from the Child Development Project (Dodge, Bates, & Pettit, 1990), we tested and corroborated the hypotheses that participants with relatively low anxiety and high APSD scores would display poorer passive avoidance learning and less interference on a spatially separated, picture-word Stroop task than controls. Consistent with hypotheses, the expected group differences in picture-word Stroop interference were found with male and female participants, whereas predicted differences in passive avoidance were specific to male participants. To the extent that response modulation deficits contributing to poor socialization among psychopathic adult offenders also characterize a subgroup of adolescents with mild conduct problems, clarification of the developmental processes that moderate the expression of this vulnerability could inform early interventions.


Costs of first-line doublet chemotherapy and lifetime medical care in advanced non-small-cell lung cancer in the United States.
The purpose of this study was to identify total lifetime medical-care costs and costs associated with first-line chemotherapy treatment among older patients with stage IIIB/IV non-small-cell lung cancer treated with commonly used two-drug chemotherapy ("doublet") regimens in the United States. Study patients included individuals aged 65 years and older who received a diagnosis of stage IIIB/IV non-small-cell lung cancer in a Surveillance, Epidemiology and End Results cancer registry between 1997 and 2002 and who received first-line treatment with commonly used doublet regimens. Patients were followed retrospectively in the Surveillance, Epidemiology and End Results-Medicare database to evaluate lifetime medical-care costs and costs while on first-line chemotherapy treatment. Pairwise comparisons of treatment costs were estimated by using nonparametric bootstrap methods. Lifetime medical-care costs totaled approximately $70,000 and on-treatment costs for first-line chemotherapy totaled approximately $30,000 among study patients and were dominated by hospitalization and physician costs. Lifetime costs were significantly higher among patients treated with first-line cisplatin/carboplatin (platinum) plus a taxane compared with those who received platinum plus gemcitabine [difference: $4781 ($1558-$8039)] or other doublet therapy [difference: $5961 ($2333-$9614)]. Total on-treatment costs for first-line chemotherapy were significantly higher among patients treated with platinum plus a taxane compared with those who received platinum plus gemcitabine [difference: $5825 ($3872-$7770)], platinum plus another agent [difference: $5968 ($3995-$7975)], or another doublet therapy [difference: $3663 ($1620-$5740)]. There is a cost differential between first-line doublet regimens in terms of lifetime and on-treatment costs. Although doublet therapy with platinum and a taxane was the most frequently utilized regimen, it was associated with the highest lifetime and on-treatment costs.


Franklin expedition lead exposure: New insights from high resolution confocal x-ray fluorescence imaging of skeletal microstructure.
In the summer of 1845, under the command of Sir John Franklin, 128 officers and men aboard Royal Navy ships HMS Erebus and HMS Terror sailed into Lancaster Sound and entered the waters of Arctic North America. The goal of this expedition was to complete the discovery of a northwest passage by navigating the uncharted area between Barrow Strait and Simpson Strait. Franklin and his crew spent the first winter at Beechey Island, where three crewmen died and were buried. In September 1846, the ships became stranded in ice off the northwest coast of King William Island, where they remained until April 1848. At that time, the crew, reduced to 105, deserted the ships and retreated south along the island's western and southern shores in a desperate attempt to reach the mainland and via the Back River, to obtain aid at a Hudson's Bay Company Post. Sadly, not one individual survived. Previous analyses of bone, hair, and soft tissue samples from expedition remains found that crewmembers' tissues contained elevated lead (Pb) levels, suggesting that Pb poisoning may have contributed to their demise; however, questions remain regarding the timing and degree of exposure and, ultimately, the extent to which the crewmembers may have been impacted. To address this historical question, we investigated three hypotheses. First, if elevated Pb exposure was experienced by the crew during the expedition, we hypothesized that those sailors who survived longer (King William Island vs. Beechey Island) would exhibit more extensive uptake of Pb in their bones and vice versa. Second, we hypothesized that Pb would be elevated in bone microstructural features forming at or near the time of death compared with older tissue. Finally, if Pb exposure played a significant role in the failure of the expedition we hypothesized that bone samples would exhibit evidence of higher and more sustained uptake of Pb than that of a contemporary comparator naval population from the 19th century. To test these hypotheses, we analyzed bone and dental remains of crew members and compared them against samples derived from the Royal Navy cemetery in Antigua. Synchrotron-based high resolution confocal X-ray fluorescence imaging was employed to visualize Pb distribution within bone and tooth microstructures at the micro scale. The data did not support our first hypothesis as Pb distribution within the samples from the two different sites was similar. Evidence of Pb within skeletal microstructural features formed near the time of death lent support to our second hypothesis but consistent evidence of a marked elevation in Pb levels was lacking. Finally, the comparative analysis with the Antigua samples did not support the hypothesis that the Franklin sailors were exposed to an unusually high level of Pb for the time period. Taken all together our skeletal microstructural results do not support the conclusion that Pb played a pivotal role in the loss of Franklin and his crew.


Evidence for heterogeneity in facioscapulohumeral muscular dystrophy (FSHD).
Facioscapulohumeral muscular dystrophy (FSHD) is a slowly progressive primary disease of muscle which is usually inherited as an autosomal dominant disorder. FSHD has been localized to the long arm of chromosome 4, specifically to the 4q3.5-qter region. Initially published linkage studies showed no evidence for heterogeneity in FSHD. In the present study we have examined individuals in seven FSHD families. Two-point lod scores show significant evidence for linkage for D4S163 (lod score 3.04 at recombination fraction .21) and D4S139 (lod score 3.84 at recombination fraction .20). D4S171 also gave a positive score (lod score 2.56 at recombination fraction .24). Significant evidence for heterogeneity was found for each of the three markers. Multipoint linkage analysis in this region resulted in a peak multipoint lod score of 6.47. The multipoint analysis supported the two-point studies with odds of 20:1 showing linkage and heterogeneity over linkage and homogeneity. Five of the seven families gave a posterior probability of > 95% of being of the linked type, while two families appeared unlinked to this region of 4q (P < .01%). Individuals in the two unlinked families met the clinical criteria for the diagnosis of FSHD, including facial weakness, clavicular flattening, scapula winging, proximal muscle weakness, and myopathic changes on muscle biopsies without inflammatory or mitochondrial pathology. This study demonstrates genetic heterogeneity in FSHD and has important implications for both genetic counseling and the elucidation of the etiology of FSHD.


Interval versus continuous training in patients with severe COPD: a randomized clinical trial.
Limited information is available regarding the physiological responses to different types of exercise training in patients with severe chronic obstructive pulmonary disease (COPD). The aim of this study was two fold: firstly, to investigate the physiological response to training at 60% of achieved peak load in patients with severe COPD; and secondly to study the effects of interval (I) versus continuous (C) training in these patients. Twenty-one patients with COPD (mean+/-SD forced expiratory volume in one second: 37+/-15% of predicted, normoxaemic at rest) were evaluated at baseline and after 8 weeks' training. Patients were randomly allocated to either I or C training. The training was performed on a cycle ergometer, 5 days a week, 30 min daily. The total work load was the same for both training programmes. C training resulted in a significant increase in oxygen consumption (V'O2) (17%, p<0.05) and a decrease in minute ventilation (V'E)/V'O2 (p<0.01) and V'E/carbon dioxide production (V'CO2) (p<0.05) at peak exercise capacity, while no changes in these measures were observed after interval training. During submaximal exercise a significant decrease was observed in lactic acid production, being most pronounced in the C-trained group (-31%, p<0.01 versus -20%, p<0.05). Only in the I-trained group did a significant increase in peak work load (17%, p<0.05) and a decrease in leg pain (p<0.05) occur. Training did not result in a significant improvement in lung function, but maximal inspiratory mouth pressure increased in both groups by 10% (C: p<0.05) and 23% (I: p<0.01). The present study shows a different physiological response pattern to interval or continuous training in chronic obstruction pulmonary disease, which might be a reflection of specific training effects in either oxidative or glycolytic muscle metabolic pathways. Further work is required to determine the role of the different exercise programmes and the particular category of patients for whom this might be beneficial.


Conformal mappings to achieve simple material parameters for transformation optics devices.
The transformation optics technique for designing novel electromagnetic and optical devices offers great control over wave behavior, but is difficult to implement primarily due to limitations in current metamaterial design and fabrication techniques. This paper demonstrates that restricting the spatial transformation to a conformal mapping can lead to much simpler material parameters for more practical implementation. As an example, a flat cylindrical-to-plane-wave conversion lens is presented and its performance validated through numerical simulations. It is shown that the lens dimensions and embedded source location can be adjusted to produce one, two, or four highly directive planar beams. Two metamaterial designs for this lens that implement the required effective medium parameters are proposed and their behavior analyzed.


Chondrogenic differentiation of human embryonic stem cell-derived cells in arginine-glycine-aspartate-modified hydrogels.
Human embryonic stem cells (hESCs) have the potential to self-renew and generate multiple cell types, producing critical building blocks for tissue engineering and regenerative medicine applications. Here, we describe the efficient derivation and chondrogenic differentiation of mesenchymal-like cells from hESCs. These cells exhibit mesenchymal stem cell (MSC) surface markers, including CD29, CD44, CD105, and platelet-derived growth factor receptor-alpha. Under appropriate growth conditions, the hESC-derived cells proliferated without phenotypic changes and maintained MSC surface markers. The chondrogenic capacity of the cells was studied in pellet culture and after encapsulation in poly(ethylene glycol)-diacrylate (PEGDA) hydrogels with exogenous extracellular proteins or arginineglycine- aspartate (RGD)-modified PEGDA hydrogels. The hESC-derived cells exhibited growth factor- dependent matrix production in pellet culture but did not produce tissue characteristic of cartilage morphology. In PEGDA hydrogels containing exogenous hyaluronic acid or type I collagen, no significant cell growth or matrix production was observed. In contrast, when these cells were encapsulated in RGDmodified poly(ethylene glycol)hydrogels, neocartilage with basophilic extracellular matrix deposition was observed within 3 weeks of culture, producing cartilage-specific gene up-regulation and extracellular matrix production. Our results indicate that precursor cells characteristic of a MSC population can be cultured from differentiating hESCs through embryoid bodies, thus holding great promise for a potentially unlimited source of cells for cartilage tissue engineering.


Signaling mechanisms of μ-opioid receptor (MOR) in the hippocampus: disinhibition versus astrocytic glutamate regulation.
μ-opioid receptor (MOR) is a class of opioid receptors that is critical for analgesia, reward, and euphoria. MOR is distributed in various brain regions, including the hippocampus, where traditionally, it is believed to be localized mainly at the presynaptic terminals of the GABAergic inhibitory interneurons to exert a strong disinhibitory effect on excitatory pyramidal neurons. However, recent intensive research has uncovered the existence of MOR in hippocampal astrocytes, shedding light on how astrocytic MOR participates in opioid signaling via glia-neuron interaction in the hippocampus. Activation of astrocytic MOR has shown to cause glutamate release from hippocampal astrocytes and increase the excitability of presynaptic axon fibers to enhance the release of glutamate at the Schaffer Collateral-CA1 synapses, thereby, intensifying the synaptic strength and plasticity. This novel mechanism involving astrocytic MOR has been shown to participate in hippocampus-dependent conditioned place preference. Furthermore, the signaling of hippocampal MOR, whose action is sexually dimorphic, is engaged in adult neurogenesis, seizure, and stress-induced memory impairment. In this review, we focus on the two profoundly different hippocampal opioid signaling pathways through either GABAergic interneuronal or astrocytic MOR. We further compare and contrast their molecular and cellular mechanisms and their possible roles in opioid-associated conditioned place preference and other hippocampus-dependent behaviors.


Selection and socialization effects of fraternities and sororities on US college student substance use: a multi-cohort national longitudinal study.
To examine how membership in fraternities and sororities relates to the prevalence and patterns of substance use in a national sample of full-time US college students. Nationally representative probability samples of US high school seniors (modal age 18 years) were followed longitudinally across two follow-up waves during college (modal ages 19/20 and 21/22). Data were collected via self-administered questionnaires from US high school seniors and college students. The longitudinal sample consisted of 10 cohorts (senior years of 1988-97) made up of 5883 full-time undergraduate students, of whom 58% were women and 17% were active members of fraternities or sororities. Active members of fraternities and sororities had higher levels of heavy episodic drinking, annual marijuana use and current cigarette smoking than non-members at all three waves. Although members of fraternities reported higher levels than non-members of annual illicit drug use other than marijuana, no such differences existed between sorority members and non-members. Heavy episodic drinking and annual marijuana use increased significantly with age among members of fraternities or sororities relative to non-members, but there were no such differential changes for current cigarette use or annual illicit drug use other than marijuana. The present study provides strong evidence that higher rates of substance use among US college students who join fraternities and sororities predate their college attendance, and that membership in a fraternity or sorority is associated with considerably greater than average increases in heavy episodic drinking and annual marijuana use during college. These findings have important implications for prevention and intervention efforts aimed toward college students, especially members of fraternities and sororities.


Deep immune profiling reveals targetable mechanisms of immune evasion in immune checkpoint inhibitor-refractory glioblastoma.
Glioblastoma (GBM) is refractory to immune checkpoint inhibitor (ICI) therapy. We sought to determine to what extent this immune evasion is due to intrinsic properties of the tumor cells versus the specialized immune context of the brain, and if it can be reversed. We used CyTOF mass cytometry to compare the tumor immune microenvironments (TIME) of human tumors that are generally ICI-refractory (GBM and sarcoma) or ICI-responsive (renal cell carcinoma), as well as mouse models of GBM that are ICI-responsive (GL261) or ICI-refractory (SB28). We further compared SB28 tumors grown intracerebrally versus subcutaneously to determine how tumor site affects TIME and responsiveness to dual CTLA-4/PD-1 blockade. Informed by these data, we explored rational immunotherapeutic combinations. ICI-sensitivity in human and mouse tumors was associated with increased T cells and dendritic cells (DCs), and fewer myeloid cells, in particular PD-L1+ tumor-associated macrophages. The SB28 mouse model of GBM responded to ICI when grown subcutaneously but not intracerebrally, providing a system to explore mechanisms underlying ICI resistance in GBM. The response to ICI in the subcutaneous SB28 model required CD4 T cells and NK cells, but not CD8 T cells. Recombinant FLT3L expanded DCs, improved antigen-specific T cell priming, and prolonged survival of mice with intracerebral SB28 tumors, but at the cost of increased Tregs. Targeting PD-L1 also prolonged survival, especially when combined with stereotactic radiation. Our data suggest that a major obstacle for effective immunotherapy of GBM is poor antigen presentation in the brain, rather than intrinsic immunosuppressive properties of GBM tumor cells. Deep immune profiling identified DCs and PD-L1+ tumor-associated macrophages as promising targetable cell populations, which was confirmed using therapeutic interventions in vivo.