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Nitrogenases are the only known enzymes that reduce molecular nitrogen (N 2 ) to ammonia. Recent findings have demonstrated that nitrogenases also reduce the greenhouse gas carbon dioxide (CO 2 ), suggesting CO 2 to be a competitor of N 2 . However, the impact of omnipresent CO 2 on N 2 fixation has not been investigated to date. Here, we study the competing reduction of CO 2 and N 2 by the two nitrogenases of Rhodobacter capsulatus , the molybdenum and the iron nitrogenase. The iron nitrogenase is almost threefold more efficient in CO 2 reduction and profoundly less selective for N 2 than the molybdenum isoform under mixtures of N 2 and CO 2 . Correspondingly, the growth rate of diazotrophically grown R. capsulatus strains relying on the iron nitrogenase notably decreased after adding CO 2 . The in vivo CO 2 activity of the iron nitrogenase facilitates the light-driven extracellular accumulation of formate and methane, one-carbon substrates for other microbes, and feedstock chemicals for a circular economy.

Importance: Transitions in insurance coverage may be associated with worse health care outcomes. Little is known about insurance stability for individuals with opioid use disorder (OUD)., Objective: To examine insurance transitions among adults with newly diagnosed OUD in the 12 months after diagnosis., Design, Setting, and Participants: Longitudinal cohort study using data from the Massachusetts Public Health Data Warehouse. The cohort includes adults aged 18 to 63 years diagnosed with incident OUD between July 1, 2014, and December 31, 2014, who were enrolled in commercial insurance or Medicaid at diagnosis; individuals diagnosed after 2014 were excluded from the main analyses due to changes in the reporting of insurance claims. Data were analyzed from November 10, 2022, to May 6, 2024., Exposure: Insurance type at time of diagnosis (commercial and Medicaid)., Main Outcomes and Measures: The primary outcome was the cumulative incidence of insurance transitions in the 12 months after diagnosis. Logistic regression models were used to generate estimated probabilities of insurance transitions by insurance type and diagnosis for several characteristics including age, race and ethnicity, and whether an individual started medication for OUD (MOUD) within 30 days after diagnosis., Results: There were 20 768 individuals with newly diagnosed OUD between July 1, 2014, and December 31, 2014. Most individuals with newly diagnosed OUD were covered by Medicaid (75.4%). Those with newly diagnosed OUD were primarily male (67% in commercial insurance, 61.8% in Medicaid). In the 12 months following OUD diagnosis, 30.4% of individuals experienced an insurance transition, with adjusted models demonstrating higher transition rates among those starting with Medicaid (31.3%; 95% CI, 30.5%-32.0%) compared with commercial insurance (27.9%; 95% CI, 26.6%-29.1%). The probability of insurance transitions was generally higher for younger individuals than older individuals irrespective of insurance type, although there were notable differences by race and ethnicity., Conclusions and Relevance: This study found that nearly 1 in 3 individuals experience insurance transitions in the 12 months after OUD diagnosis. Insurance transitions may represent an important yet underrecognized factor in OUD treatment outcomes.

The polygenic architecture of schizophrenia implicates several molecular pathways involved in synaptic function. However, it is unclear how polygenic risk funnels through these pathways to translate into syndromic illness. Using tensor decomposition, we analyze gene co-expression in the caudate nucleus, hippocampus, and dorsolateral prefrontal cortex of post-mortem brain samples from 358 individuals. We identify a set of genes predominantly expressed in the caudate nucleus and associated with both clinical state and genetic risk for schizophrenia that shows dopaminergic selectivity. A higher polygenic risk score for schizophrenia parsed by this set of genes predicts greater dopamine synthesis in the striatum and greater striatal activation during reward anticipation. These results translate dopamine-linked genetic risk variation into in vivo neurochemical and hemodynamic phenotypes in the striatum that have long been implicated in the pathophysiology of schizophrenia., (© 2024. The Author(s).)

During Drosophila oogenesis, the Oskar (OSK) RNA binding protein (RBP) determines the amount of germ plasm that assembles at the posterior pole of the oocyte. Here, we identify mechanisms that subsequently regulate germ plasm assembly in the early embryo. We show that the Smaug (SMG) RBP is transported into the germ plasm of the early embryo where it accumulates in the germ granules. SMG binds to and represses translation of the osk messenger RNA (mRNA) as well as the bruno 1 ( bru1 ) mRNA, which encodes an RBP that we show promotes germ plasm production. Loss of SMG or mutation of SMG's binding sites in the osk or bru1 mRNA results in excess translation of these transcripts in the germ plasm, accumulation of excess germ plasm, and budding of excess primordial germ cells (PGCs). Therefore, SMG triggers a posttranscriptional regulatory pathway that attenuates the amount of germ plasm in embryos to modulate the number of PGCs.

Microbes can be found in abundance many kilometers underground. While microbial metabolic capabilities have been examined across different geochemical settings, it remains unclear how changes in subsurface niches affect microbial needs to sense and respond to their environment. To address this question, we examined how microbial extracellular sensor systems vary with environmental conditions across metagenomes at different Deep Mine Microbial Observatory (DeMMO) subsurface sites. Because two-component systems (TCSs) directly sense extracellular conditions and convert this information into intracellular biochemical responses, we expected that this sensor family would vary across isolated oligotrophic subterranean environments that differ in abiotic and biotic conditions. TCSs were found at all six subsurface sites, the service water control, and the surface site, with an average of 0.88 sensor histidine kinases (HKs) per 100 genes across all sites. Abundance was greater in subsurface fracture fluids compared with surface-derived fluids, and candidate phyla radiation (CPR) bacteria presented the lowest HK frequencies. Measures of microbial diversity, such as the Shannon diversity index, revealed that HK abundance is inversely correlated with microbial diversity ( r 2 = 0.81). Among the geochemical parameters measured, HK frequency correlated most strongly with variance in dissolved organic carbon ( r 2 = 0.82). Taken together, these results implicate the abiotic and biotic properties of an ecological niche as drivers of sensor needs, and they suggest that microbes in environments with large fluctuations in organic nutrients (e.g., lacustrine, terrestrial, and coastal ecosystems) may require greater TCS diversity than ecosystems with low nutrients (e.g., open ocean).IMPORTANCEThe ability to detect extracellular environmental conditions is a fundamental property of all life forms. Because microbial two-component sensor systems convert information about extracellular conditions into biochemical information that controls their behaviors, we evaluated how two-component sensor systems evolved within the deep Earth across multiple sites where abiotic and biotic properties vary. We show that these sensor systems remain abundant in microbial consortia at all subterranean sampling sites and observe correlations between sensor system abundances and abiotic (dissolved organic carbon variation) and biotic (consortia diversity) properties. These results suggest that multiple environmental properties may drive sensor protein evolution and highlight the need for further studies of metagenomic and geochemical data in parallel to understand the drivers of microbial sensor evolution., Competing Interests: The authors declare no conflict of interest.

Preserving insurance coverage in the wake of pandemic-related job loss was a priority in early 2020. To this end, the Families First Coronavirus Response Act implemented a continuous coverage policy in Medicaid to shore up access to health insurance. Prior to the pandemic, Medicaid enrollees experienced frequent coverage disruptions, known as "churning." The effect of the continuous coverage policy on churning during the COVID-19 public health emergency (PHE) is unknown. We performed a difference-in-differences analysis of nonelderly Medicaid enrollees using longitudinal national survey data to compare a 2019-2020 cohort exposed to the policy with a control cohort in 2018-2019. We found that the policy led to reduced transitions to uninsurance among adults, although not among children. The policy prevented over 300 000 transitions to uninsurance each month. However, disenrollment from Medicaid persisted at a low rate, despite the continuous coverage policy. As the PHE unwinds, policymakers should consider long-term continuous coverage policies to minimize churning in Medicaid., Competing Interests: Conflicts of interest Please see ICMJE form(s) for author conflicts of interest. These have been provided as supplementary materials.

Alterations in fMRI-based brain functional network connectivity (FNC) are associated with schizophrenia (SCZ) and the genetic risk or subthreshold clinical symptoms preceding the onset of SCZ, which often occurs in early adulthood. Thus, age-sensitive FNC changes may be relevant to SCZ risk-related FNC. We used independent component analysis to estimate FNC from childhood to adulthood in 9,236 individuals. To capture individual brain features more accurately than single-session fMRI, we studied an average of three fMRI scans per individual. To identify potential familial risk-related FNC changes, we compared age-related FNC in first-degree relatives of SCZ patients mostly including unaffected siblings (SIB) with neurotypical controls (NC) at the same age stage. Then, we examined how polygenic risk scores for SCZ influenced risk-related FNC patterns. Finally, we investigated the same risk-related FNC patterns in adult SCZ patients (oSCZ) and young individuals with subclinical psychotic symptoms (PSY). Age-sensitive risk-related FNC patterns emerge during adolescence and early adulthood, but not before. Young SIB always followed older NC patterns, with decreased FNC in a cerebellar-occipitoparietal circuit and increased FNC in two prefrontal-sensorimotor circuits when compared to young NC. Two of these FNC alterations were also found in oSCZ, with one exhibiting reversed pattern. All were linked to polygenic risk for SCZ in unrelated individuals (R 2 varied from 0.02 to 0.05). Young PSY showed FNC alterations in the same direction as SIB when compared to NC. These results suggest that age-related neurotypical FNC correlates with genetic risk for SCZ and is detectable with MRI in young participants.

Background: The Affordable Care Act takes a "patchwork" approach to expanding coverage: Medicaid covers individuals with incomes 138% of the federal poverty level (FPL) in expansion states, while subsidized Marketplace insurance is available to those above this income cutoff., Objective: To characterize the magnitude of churning between Medicaid and Marketplace coverage and to examine the impact of the 138% FPL income cutoff on stability of coverage., Design: We measured the incidence of transitions between Medicaid and Marketplace coverage. Then, we used a differences-in-differences framework to compare insurance churning in Medicaid expansion and non-expansion states, before and after the ACA, among adults with incomes 100-200% of poverty., Participants: Non-elderly adult respondents of the Medical Expenditure Panel Survey 2010-2018 MAIN MEASURES: The annual proportion of adults who (1) transitioned between Medicaid and Marketplace coverage; (2) experienced any coverage disruption., Key Results: One million U.S. adults transitioned between Medicaid and Marketplace coverage annually. The 138% FPL cutoff in expansion states was not associated with an increase in insurance churning among individuals with incomes close to the cutoff., Conclusions: Transitions between Medicaid and Marketplace insurance are uncommon-far lower than pre-ACA analyses predicted. The 138% income cutoff does not to contribute significantly to insurance disruptions., (© 2022. The Author(s) under exclusive licence to Society of General Internal Medicine.)

Due to concerns about the risk of infectious exposures during the coronavirus disease 2019 (COVID-19) pandemic, the uptake of telemedicine has increased rapidly, aided by increased acceptance by clinicians and patients and a reduction in regulatory and reimbursement hurdles. The increased access to telemedicine may have benefits beyond the reduction in contagious risk, especially for vulnerable populations. By breaking down some of the common barriers to care for vulnerable populations, the broad implementation of telemedicine may help reduce some inequities in health care access, but telemedicine does raise other challenges that need to be considered and addressed. One vulnerable group that can benefit from telemedicine is transgender and gender nonbinary (TGNB) individuals, who have less access to both gender-affirming and general medical care due to the consequences of stigma, discrimination, and marginalization. Telemedicine allows TGNB individuals to access clinical expertise even if it is not available locally, and without the expense of travel and without the concern for exposure to discrimination and mistreatment. However, lack of access to or expertise in navigating the required technology, lack of a safe and confidential space to access care, and an unpredictable regulatory and reimbursement environment remain hurdles for harvesting the full benefits of telemedicine., Competing Interests: No competing financial interests exist., (Copyright 2022, Mary Ann Liebert, Inc., publishers.)

First-degree relatives of patients diagnosed with schizophrenia (SZ-FDRs) show similar patterns of brain abnormalities and cognitive alterations to patients, albeit with smaller effect sizes. First-degree relatives of patients diagnosed with bipolar disorder (BD-FDRs) show divergent patterns; on average, intracranial volume is larger compared to controls, and findings on cognitive alterations in BD-FDRs are inconsistent. Here, we performed a meta-analysis of global and regional brain measures (cortical and subcortical), current IQ, and educational attainment in 5,795 individuals (1,103 SZ-FDRs, 867 BD-FDRs, 2,190 controls, 942 schizophrenia patients, 693 bipolar patients) from 36 schizophrenia and/or bipolar disorder family cohorts, with standardized methods. Compared to controls, SZ-FDRs showed a pattern of widespread thinner cortex, while BD-FDRs had widespread larger cortical surface area. IQ was lower in SZ-FDRs (d = -0.42, p = 3 × 10 -5 ), with weak evidence of IQ reductions among BD-FDRs (d = -0.23, p = .045). Both relative groups had similar educational attainment compared to controls. When adjusting for IQ or educational attainment, the group-effects on brain measures changed, albeit modestly. Changes were in the expected direction, with less pronounced brain abnormalities in SZ-FDRs and more pronounced effects in BD-FDRs. To conclude, SZ-FDRs and BD-FDRs show a differential pattern of structural brain abnormalities. In contrast, both had lower IQ scores and similar school achievements compared to controls. Given that brain differences between SZ-FDRs and BD-FDRs remain after adjusting for IQ or educational attainment, we suggest that differential brain developmental processes underlying predisposition for schizophrenia or bipolar disorder are likely independent of general cognitive impairment., (© 2020 The Authors. Human Brain Mapping published by Wiley Periodicals LLC.)

We propose a novel optimization framework that integrates imaging and genetics data for simultaneous biomarker identification and disease classification. The generative component of our model uses a dictionary learning framework to project the imaging and genetic data into a shared low dimensional space. We have coupled both the data modalities by tying the linear projection coefficients to the same latent space. The discriminative component of our model uses logistic regression on the projection vectors for disease diagnosis. This prediction task implicitly guides our framework to find interpretable biomarkers that are substantially different between a healthy and disease population. We exploit the interconnectedness of different brain regions by incorporating a graph regularization penalty into the joint objective function. We also use a group sparsity penalty to find a representative set of genetic basis vectors that span a low dimensional space where subjects are easily separable between patients and controls. We have evaluated our model on a population study of schizophrenia that includes two task fMRI paradigms and single nucleotide polymorphism (SNP) data. Using ten-fold cross validation, we compare our generative-discriminative framework with canonical correlation analysis (CCA) of imaging and genetics data, parallel independent component analysis (pICA) of imaging and genetics data, random forest (RF) classification, and a linear support vector machine (SVM). We also quantify the reproducibility of the imaging and genetics biomarkers via subsampling. Our framework achieves higher class prediction accuracy and identifies robust biomarkers. Moreover, the implicated brain regions and genetic variants underlie the well documented deficits in schizophrenia., (Copyright © 2021. Published by Elsevier Inc.)

Human serum albumin (HSA) acts as a carrier for testosterone, other sex hormones, fatty acids, and drugs. However, the dynamics of testosterone's binding to HSA and the structure of its binding sites remain incompletely understood. Here, we characterize the dynamics of testosterone's binding to HSA and the stoichiometry and structural location of the binding sites using 2-dimensional nuclear magnetic resonance (2D NMR), fluorescence spectroscopy, 4,4'-dianilino-1,1'-binaphthyl-5,5'-disulfonic acid dipotassium salt partitioning, and equilibrium dialysis, complemented by molecular modeling. 2D NMR studies showed that testosterone competitively displaced 18-[13C]-oleic acid from at least 3 known fatty acid binding sites on HSA that also bind many drugs. Binding isotherms of testosterone's binding to HSA generated using fluorescence spectroscopy and equilibrium dialysis were nonlinear and the apparent dissociation constant varied with different concentrations of testosterone and HSA. The binding isotherms neither conformed to a linear binding model with 1:1 stoichiometry nor to 2 independent binding sites; the binding isotherms were most consistent with 2 or more allosterically coupled binding sites. Molecular dynamics studies revealed that testosterone's binding to fatty acid binding site 3 on HSA was associated with conformational changes at site 6, indicating that residues in in these 2 distinct binding sites are allosterically coupled. There are multiple, allosterically coupled binding sites for testosterone on HSA. Testosterone shares these binding sites on HSA with free fatty acids, which could displace testosterone from HSA under various physiological states or disease conditions, affecting its bioavailability., (© The Author(s) 2020. Published by Oxford University Press on behalf of the Endocrine Society. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Objective: To test whether a change from a telephone to mail and Internet survey in January 2018 affected the sample composition and uninsured estimates in the Gallup-Sharecare Well-Being Index., Data Sources: Gallup-Sharecare Well-Being Index (2013-2018)., Study Design: Regression discontinuity analysis identified changes after the survey redesign in the estimated U.S. uninsured rate (adults 18-64) and in the sample's demographic composition., Principal Findings: After the survey redesign, the estimated uninsured rate fell 5.3 percentage points (P < 0.001), respondents were older and disproportionately white, more likely to have a college degree, and had higher average incomes. These changes were modestly reduced by survey weights., Conclusions: The shift to a mail survey (with a web option) led to an older, more educated sample with fewer minorities, and a significant break in trend in the estimated uninsured rate., (© Health Research and Educational Trust.)

Context: The prevalence of body image disorders and anabolic-androgenic steroid (AAS) use is increasing, despite the evidence of their serious adverse health effects and despite the passage of laws regulating their sales. Here we review the evolution of the dual emerging epidemics of body image disorders and AAS use, adverse health effects of AASs, and the need for an integrated health policy and regulatory response., Evidence Acquisition: We searched for studies published prior to June 2018. Quality of evidence was low to moderate because of its observational nature; heterogeneity of eligibility criteria; variable doses; reliance on retrospective self-reported data in many studies; and variable quality of outcome ascertainment., Evidence Synthesis: Most AAS users are nonathlete young men, who use these substances to look lean and more muscular. Some of these men suffer from "muscle dysmorphia," a form of body dysmorphic disorder. AASs has been associated with cardiovascular disorders, psychiatric disorders, AAS-withdrawal hypogonadism, infertility, neurotoxic effects, musculoskeletal injuries, liver toxicity, and needle-borne infections. Potential adverse effects may be compounded by the use of other substances (e.g., opioids) and high-risk behaviors. Unregulated Internet sales of AASs and selective androgen receptor modulators, which are easily purchased without a prescription, are of concern because of their potential to fuel the epidemic among adolescents and the military., Conclusions: Integrated nationwide efforts are necessary to raise public awareness of this epidemic, to study long-term health effects of AASs and treatment strategies, and to reform regulations to stem the epidemics of AAS use and body image disorders., (Copyright © 2019 Endocrine Society.)

Issue: Kansas remains one of 17 states that have not expanded Medicaid. In 2017, the Kansas legislature voted to expand Medicaid, but former Governor Sam Brownback vetoed the measure., Goal: To examine evidence on health care coverage and access among low-income Kansans and to review the potential impact of expanding Medicaid with the possible addition of a work requirement as a condition of eligibility., Methods: Findings from a telephone survey of 1,000 low-income nonelderly adults in Kansas were compared with data on low-income adults in Ohio and Indiana, both of which expanded Medicaid., Findings and Conclusions: The uninsured rate among low-income Kansans ages 19 to 64 is 20 percent, significantly higher than rates in Ohio and Indiana. Low-income Kansans also reported comparatively more frequent delays in care because of cost, greater difficulty affording medical bills, and worse health care quality. Survey data show Medicaid expansion is favored by 77 percent of low-income Kansans, and state policymakers have expressed interest in using a Section 1115 waiver for expansion, which would include a work requirement. Our data suggest such a provision would likely have little impact on employment in Kansas, where most potential Medicaid enrollees are disabled or already employed.

In the circulation, testosterone and other sex hormones are bound to binding proteins, which play an important role in regulating their transport, distribution, metabolism, and biological activity. According to the free hormone hypothesis, which has been debated extensively, only the unbound or free fraction is biologically active in target tissues. Consequently, accurate determination of the partitioning of testosterone between bound and free fractions is central to our understanding of how its delivery to the target tissues and biological activity are regulated and consequently to the diagnosis and treatment of androgen disorders in men and women. Here, we present a historical perspective on the evolution of our understanding of the binding of testosterone to circulating binding proteins. On the basis of an appraisal of the literature as well as experimental data, we show that the assumptions of stoichiometry, binding dynamics, and the affinity of the prevailing models of testosterone binding to sex hormone-binding globulin and human serum albumin are not supported by published experimental data and are most likely inaccurate. This review offers some guiding principles for the application of free testosterone measurements in the diagnosis and treatment of patients with androgen disorders. The growing number of testosterone prescriptions and widely recognized problems with the direct measurement as well as the computation of free testosterone concentrations render this critical review timely and clinically relevant., (Copyright © 2017 Endocrine Society.)

The hippocampal formation is a brain structure integrally involved in episodic memory, spatial navigation, cognition and stress responsiveness. Structural abnormalities in hippocampal volume and shape are found in several common neuropsychiatric disorders. To identify the genetic underpinnings of hippocampal structure here we perform a genome-wide association study (GWAS) of 33,536 individuals and discover six independent loci significantly associated with hippocampal volume, four of them novel. Of the novel loci, three lie within genes (ASTN2, DPP4 and MAST4) and one is found 200 kb upstream of SHH. A hippocampal subfield analysis shows that a locus within the MSRB3 gene shows evidence of a localized effect along the dentate gyrus, subiculum, CA1 and fissure. Further, we show that genetic variants associated with decreased hippocampal volume are also associated with increased risk for Alzheimer's disease (r g =-0.155). Our findings suggest novel biological pathways through which human genetic variation influences hippocampal volume and risk for neuropsychiatric illness.

High-resolution three-dimensional magnetic resonance imaging (3D-MRI) is being increasingly used to delineate morphological changes underlying neuropsychiatric disorders. Unfortunately, artifacts frequently compromise the utility of 3D-MRI yielding irreproducible results, from both type I and type II errors. It is therefore critical to screen 3D-MRIs for artifacts before use. Currently, quality assessment involves slice-wise visual inspection of 3D-MRI volumes, a procedure that is both subjective and time consuming. Automating the quality rating of 3D-MRI could improve the efficiency and reproducibility of the procedure. The present study is one of the first efforts to apply a support vector machine (SVM) algorithm in the quality assessment of structural brain images, using global and region of interest (ROI) automated image quality features developed in-house. SVM is a supervised machine-learning algorithm that can predict the category of test datasets based on the knowledge acquired from a learning dataset. The performance (accuracy) of the automated SVM approach was assessed, by comparing the SVM-predicted quality labels to investigator-determined quality labels. The accuracy for classifying 1457 3D-MRI volumes from our database using the SVM approach is around 80%. These results are promising and illustrate the possibility of using SVM as an automated quality assessment tool for 3D-MRI.

The highly complex structure of the human brain is strongly shaped by genetic influences. Subcortical brain regions form circuits with cortical areas to coordinate movement, learning, memory and motivation, and altered circuits can lead to abnormal behaviour and disease. To investigate how common genetic variants affect the structure of these brain regions, here we conduct genome-wide association studies of the volumes of seven subcortical regions and the intracranial volume derived from magnetic resonance images of 30,717 individuals from 50 cohorts. We identify five novel genetic variants influencing the volumes of the putamen and caudate nucleus. We also find stronger evidence for three loci with previously established influences on hippocampal volume and intracranial volume. These variants show specific volumetric effects on brain structures rather than global effects across structures. The strongest effects were found for the putamen, where a novel intergenic locus with replicable influence on volume (rs945270; P = 1.08 × 10(-33); 0.52% variance explained) showed evidence of altering the expression of the KTN1 gene in both brain and blood tissue. Variants influencing putamen volume clustered near developmental genes that regulate apoptosis, axon guidance and vesicle transport. Identification of these genetic variants provides insight into the causes of variability in human brain development, and may help to determine mechanisms of neuropsychiatric dysfunction.

The purpose of this study was to examine measures of anatomical connectivity between the thalamus and lateral prefrontal cortex (LPFC) in schizophrenia and to assess their functional implications. We measured thalamocortical connectivity with diffusion tensor imaging (DTI) and probabilistic tractography in 15 patients with schizophrenia and 22 age- and sex-matched controls. The relationship between thalamocortical connectivity and prefrontal cortical blood-oxygenation-level-dependent (BOLD) functional activity as well as behavioral performance during working memory was examined in a subsample of 9 patients and 18 controls. Compared with controls, schizophrenia patients showed reduced total connectivity of the thalamus to only one of six cortical regions, the LPFC. The size of the thalamic region with at least 25% of model fibers reaching the LPFC was also reduced in patients compared with controls. The total thalamocortical connectivity to the LPFC predicted working memory task performance and also correlated with LPFC BOLD activation. Notably, the correlation with BOLD activation was accentuated in patients as compared with controls in the ventral LPFC. These results suggest that thalamocortical connectivity to the LPFC is altered in schizophrenia with functional consequences on working memory processing in LPFC.

Little is known about how individual olfactory receptor neurons (ORNs) select, from among many odor receptor genes, which genes to express. Abnormal chemosensory jump 6 (Acj6) is a POU domain transcription factor essential for the specification of ORN identity and odor receptor (Or) gene expression in the Drosophila maxillary palp, one of the two adult olfactory organs. However, the mechanism by which Acj6 functions in this process has not been investigated. Here, we systematically examine the role of Acj6 in the maxillary palp and in a major subset of antennal ORNs. We define an Acj6 binding site by a reiterative in vitro selection process. The site is found upstream of Or genes regulated by Acj6, and Acj6 binds to the site in Or promoters. Mutational analysis shows that the site is essential for Or regulation in vivo. Surprisingly, a novel ORN class in acj6 adults is found to arise from ectopic expression of a larval Or gene, which is repressed in wild type via an Acj6 binding site. Thus, Acj6 acts directly in the process of receptor gene choice; it plays a dual role, positive and negative, in the logic of the process, and acts in partitioning the larval and adult receptor repertoires.

Complex genetic disorders such as depression likely exhibit epistasis, but neural mechanisms of such gene-gene interactions are incompletely understood. 5-HTTLPR and BDNF VAL66MET, functional polymorphisms of the serotonin (5-HT) transporter (SLC6A4) and brain-derived neurotrophic factor (BDNF) gene, impact on two distinct, but interacting signaling systems, which have been related to depression and to the modulation of neurogenesis and plasticity of circuitries of emotion processing. Recent clinical studies suggest that the BDNF MET allele, which shows abnormal intracellular trafficking and regulated secretion, has a protective effect regarding the development of depression and in mice of social defeat stress. Here we show, using anatomical neuroimaging techniques in a sample of healthy subjects (n=111), that the BDNF MET allele, which is predicted to have reduced responsivity to 5-HT signaling, protects against 5-HTTLPR S allele-induced effects on a brain circuitry encompassing the amygdala and the subgenual portion of the anterior cingulate (rAC). Our analyses revealed no effect of the 5-HTTLPR S allele on rAC volume in the presence of BDNF MET alleles, whereas a significant volume reduction (P<0.001) was seen on BDNF VAL/VAL background. Interacting genotype effects were also found in structural connectivity between amygdala and rAC (P=0.002). These data provide in vivo evidence of biologic epistasis between SLC6A4 and BDNF in the human brain by identifying a neural mechanism linking serotonergic and neurotrophic signaling on the neural systems level, and have implications for personalized treatment planning in depression.

In animals, egg activation triggers a cascade of posttranscriptional events that act on maternally synthesized RNAs. We show that, in Drosophila, the PAN GU (PNG) kinase sits near the top of this cascade, triggering translation of SMAUG (SMG), a multifunctional posttranscriptional regulator conserved from yeast to humans. Although PNG is required for cytoplasmic polyadenylation of smg mRNA, it regulates translation via mechanisms that are independent of its effects on the poly(A) tail. Analyses of mutants suggest that PNG relieves translational repression by PUMILIO (PUM) and one or more additional factors, which act in parallel through the smg mRNA's 3' untranslated region (UTR). Microarray-based gene expression profiling shows that SMG is a major regulator of maternal transcript destabilization. SMG-dependent mRNAs are enriched for gene ontology annotations for function in the cell cycle, suggesting a possible causal relationship between failure to eliminate these transcripts and the cell cycle defects in smg mutants.

One of the most fundamental tenets in the field of olfaction is that each olfactory receptor neuron (ORN) expresses a single odorant receptor. However, the one receptor-one neuron principle is difficult to establish rigorously. Here we construct a receptor-to-neuron map for an entire olfactory organ in Drosophila and find that two receptor genes are coexpressed in one class of ORN. Both receptors are functional in an in vivo expression system, they are only 16% identical in amino acid sequence, and the genes that encode them are unlinked. Most importantly, their coexpression has been conserved for >45 million years. Expression of multiple odor receptors in a cell provides an additional degree of freedom for odor coding.

Objective: To determine whether prasterone administration results in improvement or stabilization of systemic lupus erythematosus (SLE) disease activity and its symptoms., Methods: Women with active SLE were treated with prasterone 200 mg/day plus standard SLE treatments or with placebo plus standard SLE treatments for up to 12 months in this randomized, double-blind investigation conducted at 27 centers. Standard SLE treatments included prednisone (/=6 weeks prior to enrollment and remain unchanged during protocol treatment. Responders were patients who experienced no clinical deterioration and had improvement or stabilization over the duration of the study in 2 disease activity measures (the SLE Disease Activity Index [SLEDAI] and the Systemic Lupus Activity Measure) and 2 quality of life measures (patient's global assessment and the Krupp Fatigue Severity Scale)., Results: A total of 381 women with SLE were enrolled. Among patients with clinically active disease at baseline (SLEDAI score >2), 86 of 147 in the prasterone group (58.5%) demonstrated improvement or stabilization without clinical deterioration, as compared with 65 of 146 in the placebo group (44.5%) (P = 0.017). Acne and hirsutism were reported in 33% and 16%, respectively, of the prasterone group and in 14% and 2%, respectively, of the placebo group (P < 0.05 for both comparisons). However, most cases of acne and hirsutism were mild and did not require withdrawal from therapy. Myalgias and oral stomatitis were reported less frequently in the prasterone group (22% and 15%, respectively) than in the placebo group (36% and 23%, respectively) (P < 0.05 for both comparisons). Serum levels of high-density lipoprotein cholesterol, triglycerides, and C3 complement significantly decreased, while levels of testosterone and, to a lesser extent, estradiol increased in the prasterone group., Conclusion: In adult women with active SLE, administration of prasterone at a dosage of 200 mg/day improved or stabilized signs and symptoms of disease and was generally well tolerated.

A 10-year-old cat that was kept on a diet consisting largely of raw liver was evaluated because of lethargy, partial anorexia, and weight loss of several months' duration. The cat's head and neck were rigidly extended, and a hard mass was palpable in the ventral cervical region. Cervical and thoracic radiography revealed proliferative bony lesions of the cervical and thoracic vertebrae as well as of the sternum and costal cartilages. Serum vitamin A concentration was 4 times normal. For reasons unrelated to hypervitaminosis A, euthanasia and necropsy were performed 6 months after evaluation. The skull and the cervical and first few thoracic vertebrae were rigidly fused, and the vertebral architecture was altered by deposition of new bone. The sternum and costal cartilages were similarly affected. The historical, physical, radiographic, laboratory, and postmortem findings were consistent with the diagnosis of hypervitaminosis A. On the basis of findings in this cat, hypervitaminosis A should be suspected in any sick cat fed a diet consisting partly or completely of raw liver.

Between 1960 and April, 1980, 302 patients were explored for primary hyperparathyroidism at Emory University Hospital. Seventeen of these 302 patients had undergone initial surgical exploration elsewhere, and were referred for persistent hypercalcemia. Of the 285 patients who were operated on at our institution, 14 subsequently had persistent hypercalcemia, and two had recurrent hypercalcemia. Twenty-eight of these 33 patients had had re-exploration, and 23 (82%) are now normocalcemic. Twenty-eight abnormal glands were found; 22 (79%) were retrievable via the neck and six (21%) required sternotomy. Of those glands removed via the neck, nine were in a near normal location and 13 in a subnormal or abnormal location. The causes of initial surgical failures were abnormally located glands, in ten patients, insufficient explorations of the neck in eight patients, hyperfunctioning parathyroid remnants in three patients, inadequate plans for hyperplasia in two patients, and carcinoma in one patient. In 57% of our patients who underwent successful re-exploration, the glands were correctly localized before operation by angiographic examination or selective venous sampling for parathormone. Thorough exploration and obtainment of biopsy specimens of all parathyroid glands are recommended in order to keep initial failures to a minimum. If reoperation is required, localization using CT scan, angiography and selective venous sampling are recommended.

Previous studies have shown that some patients with chronic obstructive lung disease and hypercapnia will respond to medroxyprogesterone with improvement in arterial blood gases. The exact mechanism of this effect is unclear but it is presumed to be a result of ventilatory stimulation. To determine whether the ability to correct arterial blood gas abnormalities by voluntary hyperventilation would predict a subsequent favourable response to progesterone, we studied 11 subjects with chronic obstructive lung disease and chronic hypercapnia. Five subjects had chronic obstructive lung disease of moderate severity with mean (SE) FEV1 1.8 (0.34) 1 maximum voluntary ventilation (MVV) 40.4 (7.16) 1/min-1, arterial oxygen tension (Pao2) 53.8 (2.40 mm Hg, and arterial carbon dioxide tension Paco2) 49.6 (3.91) mm Hg, and were able to normalise their blood gas tensions during voluntary hyperventilation (Pao2 85.4 (8.01) mm Hg; Paco2 32.8 (3.43) mm Hg). Six subjects had severe chronic obstructive lung disease with FEV1 0.77 (0.12) 1, MVV 19 (3.09) 1/min-1, Pao2 60.0 (2.89) mm Hg and Paco2 50.5 (1.38) mm Hg, and they could not significantly alter their blood gases with voluntary hyperventilation (Pao2 62.5 (3.19) mm Hg, Paco2 49.7 (1.84) mm Hg). The groups were similar in age, height, weight, and resting Pao2 and Paco2. Each subject received one month of oral placebo and one month of medroxyprogesterone acetate (Provera). 20 mg orally thrice daily, given in a randomised, double blind fashion. The groups responded similarly with a significantly higher Pao2 and lower Paco2 while having medroxyprogesterone acetate than while having placebo. Two patients with polycythaemia showed a reduction in haemoglobin concentration while taking progesterone. It is concluded that the response to medroxyprogesterone is not predictable from spirometric or blood gas changes after voluntary hyperventilation.