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AMPA receptors (AMPARs) are tetrameric ligand-gated channels made up of combinations of GluA1-4 subunits encoded by GRIA1-4 genes. GluA2 has an especially important role because, following post-transcriptional editing at the Q607 site, it renders heteromultimeric AMPARs Ca 2+ -impermeable, with a linear relationship between current and trans-membrane voltage. Here, we report heterozygous de novo GRIA2 mutations in 28 unrelated patients with intellectual disability (ID) and neurodevelopmental abnormalities including autism spectrum disorder (ASD), Rett syndrome-like features, and seizures or developmental epileptic encephalopathy (DEE). In functional expression studies, mutations lead to a decrease in agonist-evoked current mediated by mutant subunits compared to wild-type channels. When GluA2 subunits are co-expressed with GluA1, most GRIA2 mutations cause a decreased current amplitude and some also affect voltage rectification. Our results show that de-novo variants in GRIA2 can cause neurodevelopmental disorders, complementing evidence that other genetic causes of ID, ASD and DEE also disrupt glutamatergic synaptic transmission.

Purpose: TANGO2-related disorders were first described in 2016 and prior to this publication, only 15 individuals with TANGO2-related disorder were described in the literature. Primary features include metabolic crisis with rhabdomyolysis, encephalopathy, intellectual disability, seizures, and cardiac arrhythmias. We assess whether genotype and phenotype of TANGO2-related disorder has expanded since the initial discovery and determine the efficacy of exome sequencing (ES) as a diagnostic tool for detecting variants., Methods: We present a series of 14 individuals from 11 unrelated families with complex medical and developmental histories, in whom ES or microarray identified compound heterozygous or homozygous variants in TANGO2., Results: The initial presentation of patients with TANGO2-related disorders can be variable, including primarily neurological presentations. We expand the phenotype and genotype for TANGO2, highlighting the variability of the disorder., Conclusion: TANGO2-related disorders can have a more diverse clinical presentation than previously anticipated. We illustrate the utility of routine ES data reanalysis whereby discovery of novel disease genes can lead to a diagnosis in previously unsolved cases and the need for additional copy-number variation analysis when ES is performed.

ZMIZ1 is a coactivator of several transcription factors, including p53, the androgen receptor, and NOTCH1. Here, we report 19 subjects with intellectual disability and developmental delay carrying variants in ZMIZ1. The associated features include growth failure, feeding difficulties, microcephaly, facial dysmorphism, and various other congenital malformations. Of these 19, 14 unrelated subjects carried de novo heterozygous single-nucleotide variants (SNVs) or single-base insertions/deletions, 3 siblings harbored a heterozygous single-base insertion, and 2 subjects had a balanced translocation disrupting ZMIZ1 or involving a regulatory region of ZMIZ1. In total, we identified 13 point mutations that affect key protein regions, including a SUMO acceptor site, a central disordered alanine-rich motif, a proline-rich domain, and a transactivation domain. All identified variants were absent from all available exome and genome databases. In vitro, ZMIZ1 showed impaired coactivation of the androgen receptor. In vivo, overexpression of ZMIZ1 mutant alleles in developing mouse brains using in utero electroporation resulted in abnormal pyramidal neuron morphology, polarization, and positioning, underscoring the importance of ZMIZ1 in neural development and supporting mutations in ZMIZ1 as the cause of a rare neurodevelopmental syndrome., (Copyright © 2018 American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.)

Conditional power combines the findings of a partially completed study with assumptions about the future. The goal is to estimate the probability that the eventual study result will be incompatible with a criterion value, such as acceptable risk or the null hypothesis. Some history and motivation for conditional power calculations are provided, with examples illustrating the application to drug safety studies. This is an expository article suggesting that conditional power, which is well-established in clinical trials research, also has application to observational studies. The utility may be highest in regulatory settings where resources are limited and interim decisions have to be made accurately in the shortest possible time.

Depth is usually considered the main driver of Lake Trout intraspecific diversity across lakes in North America. Given that Great Bear Lake is one of the largest and deepest freshwater systems in North America, we predicted that Lake Trout intraspecific diversity to be organized along a depth axis within this system. Thus, we investigated whether a deep-water morph of Lake Trout co-existed with four shallow-water morphs previously described in Great Bear Lake. Morphology, neutral genetic variation, isotopic niches, and life-history traits of Lake Trout across depths (0-150 m) were compared among morphs. Due to the propensity of Lake Trout with high levels of morphological diversity to occupy multiple habitat niches, a novel multivariate grouping method using a suite of composite variables was applied in addition to two other commonly used grouping methods to classify individuals. Depth alone did not explain Lake Trout diversity in Great Bear Lake; a distinct fifth deep-water morph was not found. Rather, Lake Trout diversity followed an ecological continuum, with some evidence for adaptation to local conditions in deep-water habitat. Overall, trout caught from deep-water showed low levels of genetic and phenotypic differentiation from shallow-water trout, and displayed higher lipid content (C:N ratio) and occupied a higher trophic level that suggested an potential increase of piscivory (including cannibalism) than the previously described four morphs. Why phenotypic divergence between shallow- and deep-water Lake Trout was low is unknown, especially when the potential for phenotypic variation should be high in deep and large Great Bear Lake. Given that variation in complexity of freshwater environments has dramatic consequences for divergence, variation in the complexity in Great Bear Lake (i.e., shallow being more complex than deep), may explain the observed dichotomy in the expression of intraspecific phenotypic diversity between shallow- vs. deep-water habitats. The ambiguity surrounding mechanisms driving divergence of Lake Trout in Great Bear Lake should be seen as reflective of the highly variable nature of ecological opportunity and divergent natural selection itself.

Polymicrogyria is a malformation of cortical development. The aetiology of polymicrogyria remains poorly understood. Using whole-exome sequencing we found de novo heterozygous missense GRIN1 mutations in 2 of 57 parent-offspring trios with polymicrogyria. We found nine further de novo missense GRIN1 mutations in additional cortical malformation patients. Shared features in the patients were extensive bilateral polymicrogyria associated with severe developmental delay, postnatal microcephaly, cortical visual impairment and intractable epilepsy. GRIN1 encodes GluN1, the essential subunit of the N-methyl-d-aspartate receptor. The polymicrogyria-associated GRIN1 mutations tended to cluster in the S2 region (part of the ligand-binding domain of GluN1) or the adjacent M3 helix. These regions are rarely mutated in the normal population or in GRIN1 patients without polymicrogyria. Using two-electrode and whole-cell voltage-clamp analysis, we showed that the polymicrogyria-associated GRIN1 mutations significantly alter the in vitro activity of the receptor. Three of the mutations increased agonist potency while one reduced proton inhibition of the receptor. These results are striking because previous GRIN1 mutations have generally caused loss of function, and because N-methyl-d-aspartate receptor agonists have been used for many years to generate animal models of polymicrogyria. Overall, our results expand the phenotypic spectrum associated with GRIN1 mutations and highlight the important role of N-methyl-d-aspartate receptor signalling in the pathogenesis of polymicrogyria.

Many fishes express high levels of intraspecific variability, often linked to resource partitioning. Several studies show that a species' evolutionary trajectory of adaptive divergence can undergo reversals caused by changes in its environment. Such a reversal in neutral genetic and morphological variation among lake trout Salvelinus namaycush ecomorphs appears to be underway in Lake Superior. However, a water depth gradient in neutral genetic divergence was found to be associated with intraspecific diversity in the lake. To investigate patterns of adaptive immunogenetic variation among lake trout ecomorphs, we used Illumina high-throughput sequencing. The population's genetic structure of the major histocompatibility complex (MHC Class IIβ exon 2) and 18 microsatellite loci were compared to disentangle neutral and selective processes at a small geographic scale. Both MHC and microsatellite variation were partitioned more by water depth stratum than by ecomorph. Several metrics showed strong clustering by water depth in MHC alleles, but not microsatellites. We report a 75% increase in the number of MHC alleles shared between the predominant shallow and deep water ecomorphs since a previous lake trout MHC study at the same locale (c. 1990s data). This result is consistent with the reverse speciation hypothesis, although adaptive MHC polymorphisms persist along an ecological gradient. Finally, results suggested that the lake trout have multiple copies of the MHC II locus consistent with a historic genomic duplication event. Our findings indicated that conservation approaches for this species could focus on managing various ecological habitats by depth, in addition to regulating the fisheries specific to ecomorphs.

Regulated inter-mitochondrial fusion/fission is essential for maintaining optimal mitochondrial respiration and control of apoptosis and autophagy. In mammals, mitochondrial fusion is controlled by outer membrane GTPases MFN1 and MFN2 and by inner membrane (IM) GTPase OPA1. Disordered mitochondrial fusion/fission contributes to various pathologies, and MFN2 or OPA1 mutations underlie neurodegenerative diseases. Here, we show that the WBSCR16 protein is primarily associated with the outer face of the inner mitochondrial membrane and is important for mitochondrial fusion. We provide evidence of a WBSCR16/OPA1 physical interaction in the intact cell and of a WBSCR16 function as an OPA1-specific guanine nucleotide exchange factor (GEF). Homozygosity for a Wbscr16 mutation causes early embryonic lethality, whereas neurons of mice heterozygous for the mutation have mitochondria with reduced membrane potential and increased susceptibility to fragmentation upon exposure to stress, suggesting roles for WBSCR16 deficits in neuronal pathologies., (Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.)

Background: We aimed for a comprehensive delineation of genetic, functional and phenotypic aspects of GRIN2B encephalopathy and explored potential prospects of personalised medicine., Methods: Data of 48 individuals with de novo GRIN2B variants were collected from several diagnostic and research cohorts, as well as from 43 patients from the literature. Functional consequences and response to memantine treatment were investigated in vitro and eventually translated into patient care., Results: Overall, de novo variants in 86 patients were classified as pathogenic/likely pathogenic. Patients presented with neurodevelopmental disorders and a spectrum of hypotonia, movement disorder, cortical visual impairment, cerebral volume loss and epilepsy. Six patients presented with a consistent malformation of cortical development (MCD) intermediate between tubulinopathies and polymicrogyria. Missense variants cluster in transmembrane segments and ligand-binding sites. Functional consequences of variants were diverse, revealing various potential gain-of-function and loss-of-function mechanisms and a retained sensitivity to the use-dependent blocker memantine. However, an objectifiable beneficial treatment response in the respective patients still remains to be demonstrated., Conclusions: In addition to previously known features of intellectual disability, epilepsy and autism, we found evidence that GRIN2B encephalopathy is also frequently associated with movement disorder, cortical visual impairment and MCD revealing novel phenotypic consequences of channelopathies., Competing Interests: Competing interests: SFT is a consultant of Janssen Pharmaceuticals, Inc., Pfizer Inc., Boehringer Ingelheim Pharma GmbH & Co. KG, and co-founder of NeurOp Inc., (© Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.)

Mutations in bone morphogenetic protein 1 (BMP1) in humans or deletion of BMP1 and related protease tolloid like 1 (TLL1) in mice lead to osteogenesis imperfecta (OI). Here, we show progressive periodontal defects in mice in which both BMP1 and TLL1 have been conditionally ablated, including malformed periodontal ligament (PDL) (recently shown to play key roles in normal alveolar bone formation), significant loss in alveolar bone mass ( P < 0.01), and a sharp reduction in cellular cementum. Molecular mechanism studies revealed a dramatic increase in the uncleaved precursor of type I collagen (procollagen I) and a reduction in dentin matrix protein 1 (DMP1), which is partially responsible for defects in extracellular matrix (ECM) formation and mineralization. We also showed a marked increase in the expression of matrix metallopeptidase 13 (MMP13) and tartrate-resistant acid phosphatase (TRAP), leading to an acceleration in periodontal breakdown. Finally, we demonstrated that systemic application of antibiotics significantly improved the alveolar bone and PDL damage of the knockdown phenotype, which are thus shown to be partially secondary to pathogen-induced inflammation. Together, identification of the novel roles of BMP1 and TLL1 in maintaining homeostasis of periodontal formation, partly via biosynthetic processing of procollagen I and DMP1, provides novel insights into key contributions of the extracellular matrix environment to periodontal homeostasis and contributes toward understanding of the pathology of periodontitis.

Information that is not made explicit is nonetheless embedded in most of our standard procedures. In its simplest form, embedded information may take the form of prior knowledge held by the researcher and presumed to be agreed to by consumers of the research product. More interesting are the settings in which the prior information is held unconsciously by both researcher and reader, or when the very form of an "effective procedure" incorporates its creator's (unspoken) understanding of a problem. While it may not be productive to exhaustively detail the embedded or tacit knowledge that manifests itself in creative scientific work, at least at the beginning, we may want to routinize methods for extracting and documenting the ways of thinking that make "experts" expert. We should not back away from both expecting and respecting the tacit knowledge the pervades our work and the work of others.

Understanding the emergence of species through the process of ecological speciation is a central question in evolutionary biology which also has implications for conservation and management. Lake trout (Salvelinus namaycush) is renowned for the occurrence of different ecotypes linked to resource and habitat use throughout North America. We aimed to unravel the fine genetic structure of the four lake trout ecotypes in Lake Superior. A total of 486 individuals from four sites were genotyped at 6822 filtered SNPs using RADseq technology. Our results revealed different extent of morphological and genetic differentiation within the different sites. Overall, genetic differentiation was weak but significant and was on average three times higher between sites (mean F ST  = 0.016) than between ecotypes within sites (mean F ST  = 0.005) indicating higher level of gene flow or a more recent shared ancestor between ecotypes within each site than between populations of the same ecotype. Evidence of divergent selection was also found between ecotypes and/or in association with morphological variation. Outlier loci found in genes related to lipid metabolism and visual acuity were of particular interest in this context of ecotypic divergence. However, we did not find clear indication of parallelism at the genomic level, despite the presence of phenotypic parallelism among some ecotypes from different sampling sites. Overall, the occurrence of different levels of both genomic and phenotypic differentiation between ecotypes within each site with several differentiated loci linked to relevant biological functions supports the presence of a continuum of divergence in lake trout., (© 2017 John Wiley & Sons Ltd.)

Introduction: Mutations in the proteinase bone morphogenetic protein-1 (BMP1) were recently identified in patients with osteogenesis imperfecta, which can be associated with type 1 dentinogenesis imperfecta. BMP1 is co-expressed in various tissues and has overlapping activities with the closely related proteinase mammalian tolloid-like 1 (TLL1). In this study we investigated whether removing the overlapping activities of BMP1 and TLL1 affects the mineralization of tooth root dentin., Methods: Floxed alleles of the BMP1 and TLL1 genes were excised via ubiquitously expressed Cre induced by tamoxifen treatment beginning at 3 days of age (harvested at 3 weeks of age) or beginning at 4 weeks of age (harvested at 8 weeks of age). Multiple techniques, including x-ray analysis, double-labeling with calcein and alizarin red stains for measurement of dentin formation rate, and histologic and immunostaining assays, were used to analyze the dentin phenotype., Results: BMP1/TLL1 double knockout mice displayed short and thin root dentin, defects in dentin mineralization, and delayed tooth eruption. Molecular mechanism studies revealed accumulation of collagens in dentin and a sharp reduction in non-collagenous proteins such as dentin matrix protein 1 and dentin sialophosphoprotein. Furthermore, we found a strong reduction in tartrate-resistant acid phosphatase, which is likely caused by defects in bone cells., Conclusions: BMP1/TLL1 appear to play crucial roles in maintaining extracellular matrix homeostasis essential to root formation and dentin mineralization., Competing Interests: The authors deny any conflicts of interest related to this study. This research is original and free of conflict of interest., (Copyright © 2016 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.)

Closely related extracellular metalloproteinases bone morphogenetic protein 1 (BMP1) and mammalian Tolloid-like 1 (mTLL1) are co-expressed in various tissues and have been suggested to have overlapping roles in the biosynthetic processing of extracellular matrix components. Early lethality of mice null for the BMP1 gene Bmp1 or the mTLL1 gene Tll1 has impaired in vivo studies of these proteinases. To overcome issues of early lethality and functional redundancy we developed the novel BT KO mouse strain, with floxed Bmp1 and Tll1 alleles, for induction of postnatal, simultaneous ablation of the two genes. We previously showed these mice to have a skeletal phenotype that includes elements of osteogenesis imperfecta (OI), osteomalacia, and deficient osteocyte maturation, observations validated by the finding of BMP1 mutations in a subset of human patients with OI-like phenotypes. However, the roles of BMP1-like proteinase in non-skeletal tissues have yet to be explored, despite the supposed importance of putative substrates of these proteinases in such tissues. Here, we employ BT KO mice to investigate potential roles for these proteinases in skin. Loss of BMP1-like proteinase activity is shown to result in markedly thinned and fragile skin with unusually densely packed collagen fibrils and delayed wound healing. We demonstrate deficits in the processing of collagens I and III, decorin, biglycan, and laminin 332 in skin, which indicate mechanisms whereby BMP1-like proteinases affect the biology of this tissue. In contrast, lack of effects on collagen VII processing or deposition indicates this putative substrate to be biosynthetically processed by non-BMP1-like proteinases., (Copyright © 2016 International Society of Matrix Biology. Published by Elsevier B.V. All rights reserved.)

Background: Adaptive radiation involving a colonizing phenotype that rapidly evolves into at least one other ecological variant, or ecotype, has been observed in a variety of freshwater fishes in post-glacial environments. However, few studies consider how phenotypic traits vary with regard to neutral genetic partitioning along ecological gradients. Here, we present the first detailed investigation of lake trout Salvelinus namaycush that considers variation as a cline rather than discriminatory among ecotypes. Genetic and phenotypic traits organized along common ecological gradients of water depth and geographic distance provide important insights into diversification processes in a lake with high levels of human disturbance from over-fishing., Results: Four putative lake trout ecotypes could not be distinguished using population genetic methods, despite morphological differences. Neutral genetic partitioning in lake trout was stronger along a gradient of water depth, than by locality or ecotype. Contemporary genetic migration patterns were consistent with isolation-by-depth. Historical gene flow patterns indicated colonization from shallow to deep water. Comparison of phenotypic (Pst) and neutral genetic variation (Fst) revealed that morphological traits related to swimming performance (e.g., buoyancy, pelvic fin length) departed more strongly from neutral expectations along a depth gradient than craniofacial feeding traits. Elevated phenotypic variance with increasing water depth in pelvic fin length indicated possible ongoing character release and diversification. Finally, differences in early growth rate and asymptotic fish length across depth strata may be associated with limiting factors attributable to cold deep-water environments., Conclusion: We provide evidence of reductions in gene flow and divergent natural selection associated with water depth in Lake Superior. Such information is relevant for documenting intraspecific biodiversity in the largest freshwater lake in the world for a species that recently lost considerable genetic diversity and is now in recovery. Unknown is whether observed patterns are a result of an early stage of incipient speciation, gene flow-selection equilibrium, or reverse speciation causing formerly divergent ecotypes to collapse into a single gene pool.

A generalist strategy, as an adaptation to environmental heterogeneity, is common in Arctic freshwater systems, often accompanied, however, by intraspecific divergence that promotes specialization in niche use. To better understand how resources may be partitioned in a northern system that supports intraspecific diversity of Lake Trout, trophic niches were compared among four shallow-water morphotypes in Great Bear Lake (N65 ° 56' 39″, W120 ° 50' 59″). Bayesian mixing model analyses of stable isotopes of carbon and nitrogen were conducted on adult Lake Trout. Major niche overlap in resource use among four Lake Trout morphotypes was found within littoral and pelagic zones, which raises the question of how such polymorphism can be sustained among opportunistic generalist morphotypes. Covariances of our morphological datasets were tested against δ 13 C and δ 15 N values. Patterns among morphotypes were mainly observed for δ 15 N. This link between ecological and morphological differentiation suggested that selection pressure(s) operate at the trophic level (δ 15 N), independent of habitat, rather than along the habitat-foraging opportunity axis (δ 13 C). The spatial and temporal variability of resources in Arctic lakes, such as Great Bear Lake, may have favored the presence of multiple generalists showing different degrees of omnivory along a weak benthic-pelagic gradient. Morphs 1-3 had more generalist feeding habits using both benthic and pelagic habitats than Morph 4, which was a top-predator specialist in the pelagic habitat. Evidence for frequent cannibalism in Great Bear Lake was found across all four morphotypes and may also contribute to polymorphism. We suggest that the multiple generalist morphs described here from Great Bear Lake are a unique expression of diversity due to the presumed constraints on the evolution of generalists and contrast with the development of multiple specialists, the standard response to intraspecific divergence.

Osteogenesis imperfecta (OI), or brittle bone disease, is most often caused by dominant mutations in the collagen I genes COL1A1/COL1A2, whereas rarer recessive OI is often caused by mutations in genes encoding collagen I-interacting proteins. Recently, mutations in the gene for the proteinase bone morphogenetic 1 (BMP1) were reported in two recessive OI families. BMP1 and the closely related proteinase mammalian tolloid-like 1 (mTLL1) are co-expressed in various tissues, including bone, and have overlapping activities that include biosynthetic processing of procollagen precursors into mature collagen monomers. However, early lethality of Bmp1- and Tll1-null mice has precluded use of such models for careful study of in vivo roles of their protein products. Here we employ novel mouse strains with floxed Bmp1 and Tll1 alleles to induce postnatal, simultaneous ablation of the two genes, thus avoiding barriers of Bmp1(-/-) and Tll1(-/-) lethality and issues of functional redundancy. Bones of the conditionally null mice are dramatically weakened and brittle, with spontaneous fractures-defining features of OI. Additional skeletal features include osteomalacia, thinned/porous cortical bone, reduced processing of procollagen and dentin matrix protein 1, remarkably high bone turnover and defective osteocyte maturation that is accompanied by decreased expression of the osteocyte marker and Wnt-signaling inhibitor sclerostin, and by marked induction of canonical Wnt signaling. The novel animal model presented here provides new opportunities for in-depth analyses of in vivo roles of BMP1-like proteinases in bone and other tissues, and for their roles, and for possible therapeutic interventions, in OI., (© The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Two previously described lacustrine cisco Coregonus spp. morphs [i.e. a small (<300 mm fork length, L(F)), low-gillraker (≤44) morph and a large (≥300 mm L(F) ), high-gillraker (≥45) morph] from Great Slave Lake, NT, Canada, were found to be synonymous with cisco Coregonus artedi. Geometric body shape did not differ between the two size classes nor could they be differentiated by 24 size-corrected linear measurements, indicating that the two groups had similar phenotypes. Strong, positive correlations between all linear characters and geometric centroid size (a composite variable of fish body length, mass and age) suggested that body morphology changed with age as fish grew. Total gillraker number (N(GR)) increased with L(F) according to: N(GR) = 36.3 + 0.034L(F). Differences in gillraker number and phenotype with age and size were explained by shifts in habitat and trophic resource use. Relative abundance within 0-30, 30-60, 60-90 and >90 m depth strata differed between size classes suggesting that morphology changed when fish shifted their habitat as they grew older. Large C. artedi had lower δ(13)C and slightly higher δ(15)N, indicating greater reliance on pelagic prey resources (i.e. more or larger zooplankton, such as Mysis spp.), compared to small C. artedi, which relied slightly more on benthic prey. Gillraker shape and number have always been used as key diagnostic characters in coregonine taxonomy; based on the findings presented here, ontogenetic shifts should be accounted for in resulting classifications., (© 2013 The Authors. Journal of Fish Biology © 2013 The Fisheries Society of the British Isles.)

Decabromodiphenyl ether (BDE 209) is the main congener in the commonly used commercial flame retardant mixture, "deca-BDE". There is evidence showing that fish can debrominate BDE 209 into potentially more toxic congeners. The objective of this study was to evaluate BDE 209 uptake and its potential effects on juvenile lake whitefish (Coregonus clupeaformis). Lake whitefish were fed BDE 209 at four nominal concentrations (control, 0.1, 1, and 2 microg/g-diet) for 30 days. Livers and carcasses were analyzed for 11 polybrominated diphenyl ether (PBDE) congeners (BDE 47, 99, 100, 153, 154, 196, 197, 206, 207, 208, and 209) and daily otolith increment width was measured as an estimate of growth before and after exposure. Four congeners (BDE 206, 207, 208, and 209) were detected in livers and carcasses. Hepatic BDE 209 concentrations in the 1 and 2 microg/g treatments were significantly higher than in the control group (1.25 and 5.80 nmol/g-lipid compared to 0.183 nmol/g-lipid). The concentration of BDE 209 detected in the tissues of the control group resulted from BDE 209 in the base diets. Concentrations of all congeners from the 1 and 2 microg/g groups were higher in livers than carcasses, indicating the liver was the primary organ of BDE 209 accumulation. Compared to the fraction in diets, the molar fraction of BDE 209 was lower in livers and carcasses, whereas the fractions of BDE 206, 207, and 208 were higher. These different distributions of PBDE congeners resulted from differential adsorption and metabolism. One congener, BDE 206, could be a major metabolite from BDE 209 debromination. Otolith increment widths were narrower in fish from the highest diet concentration administered, suggesting BDE 209 may have affected growth rates. In conclusion, this in vivo study with lake whitefish showed that BDE 209 was debrominated into lower PBDE congeners and that exposure to 2 microg/g may have affected fish growth.

Background: National initiatives offering non-nucleoside reverse transcriptase inhibitor (NNRTI)-based combination antiretroviral therapy (cART) have expanded in sub-Saharan Africa. The Tshepo study is the first clinical trial evaluating the long-term efficacy and tolerability of efavirenz versus nevirapine-based cART among adults in Botswana., Methods: A 3-year randomized study (n = 650) using a 3 x 2 x 2 factorial design comparing efficacy and tolerability among: (i) zidovudine/lamivudine versus zidovudine/didanosine versus stavudine/lamivudine; (ii) efavirenz versus nevirapine; and (iii) community-based supervision versus standard adherence strategies. This paper focuses on comparison (ii)., Results: There was no significant difference by assigned NNRTI in time to virological failure with resistance (log-rank P = 0.14), nevirapine versus efavirenz [risk ratio (RR) 1.54, 95% CI 0.86-2.70]. Rates of virological failure with resistance were 9.6% nevirapine-treated (95% CI 6.8-13.5) versus 6.6% efavirenz-treated (95% CI 4.2-10.0) at 3 years. Women receiving nevirapine-based cART trended towards higher virological failure rates when compared with efavirenz-treated women, Holm-corrected (log-rank P = 0.072), nevirapine versus efavirenz (RR 2.22, 95% CI 0.94-5.00). A total of 139 patients had 176 treatment-modifying toxicities, with a shorter time to event in nevirapine-treated versus efavirenz-treated patients (RR 1.85, 1.20-2.86; log-rank P = 0.0002)., Conclusion: Tshepo-treated patients had excellent overall immunological and virological outcomes, and no significant differences were observed by randomized NNRTI comparison. Nevirapine-treated women trended towards higher virological failure with resistance compared with efavirenz-treated women. Nevirapine-treated adults had higher treatment modifying toxicity rates when compared with those receiving efavirenz. Nevirapine-based cART can continue to be offered to women in sub-Saharan Africa if patient education concerning toxicity is emphasized, routine safety monitoring chemistries are performed and the potential risk of efavirenz-related teratogenicity is considered.

Background: The ability of nucleoside reverse transcriptase inhibitors (NRTIs) to inhibit human mitochondrial polymerase-gamma results in impaired synthesis of mitochondrial enzymes that generate adenosine triphosphate (ATP) by oxidative phosphorylation. This has been associated with several long-term mitochondrial toxicities, which include lactic acidosis and pancreatitis, peripheral neuropathy, and lipoatrophy., Methods: Enrolled highly active antiretroviral therapy (HAART)-treated adults have completed nearly 2 years of follow-up as part of the ongoing randomized clinical trial Adult Antiretroviral Treatment and Drug Resistance (Tshepo) study. All patients were intensively screened for the presence of ARV-related toxicities., Results: Six hundred fifty adults (69% female) were initiated on NRTI-based HAART. Overall, 2.0% of patients developed moderate to severe symptomatic hyperlactatemia, with 7 (1.0%), all female, diagnosed with lactic acidosis. Female gender (P = 0.008) and being overweight, namely having a body mass index (BMI) of greater than 25 (P = 0.001), were predictive for the development of moderate to severe symptomatic hyperlactatemia or lactic acidosis. Older age (age >40 years) showed a statistical trend (P = 0.053) as a predictor for the development of toxicity, whereas exposure to d4T and/or ddI for 6 or more months was not predictive (P = 0.102). Those diagnosed with lactic acidosis had a mean BMI of 32.38 (interquartile range [IQR] = 29.4 to 35) at the time of toxicity and had been receiving HAART for a mean of 12.1 months (IQR = 7 to 20.8). Four of the 7 (57%) died of lactic acidosis and/or hemorrhagic pancreatitis; these 4 patients also had a comorbid diagnosis of severe clinical pancreatitis with grade 3/4 lipase elevations and abdominal symptoms at the time of their demise., Conclusions: Rates of lactic acidosis appear to be higher in southern Africa when compared with rates previously described elsewhere. Risk factors for the development of moderate to severe symptomatic hyperlactatemia or lactic acidosis appear to be multifactorial but include female gender and having a BMI of greater than 25. Additional studies are ongoing to evaluate for other possible risk factors, such as host genetic differences.

Background: Millions of HIV-infected women in developing countries are in need of safe and highly effective antiretroviral therapy. Pregnancy rates are usually high in developing countries, and efavirenz (EFV) use in women of childbearing age is of concern because of its potential teratogenicity., Methods: As part of a prospective study comparing 6 initial highly active antiretroviral therapy (HAART) regimens, 3 of which contained EFV, pregnancy and birth outcomes were evaluated among female participants enrolled in a randomized clinical trial in Botswana. Before enrollment, all female participants indicated a willingness to avoid pregnancy for the 3-year duration of the study. Monthly urine pregnancy testing and regular contraceptive education and counseling were given to all women on study., Results: Four hundred fifty-one (69.4%) of 650 enrolled study participants were female and experienced 71 pregnancies, for a rate of 7.9 per 100 person-years during the study. The mean time from HAART initiation to time of first pregnancy was 385 days. The median birth weight of babies was 2950 g (interquartile range: 2700-3250 g); the gender of babies (24 female and 15 male) and occurrence of early pregnancy loss (42%) and stillbirths (3%) did not differ between EFV- and non-EFV-exposed pregnancies (P=0.7). First-trimester EFV exposure occurred in 38 (53.5%) of the 71 pregnancies; 22 (57.9%) of these 38 pregnancies resulted in live births. One infant (4.5%) of the 22 EFV-exposed live births had a congenital abnormality with right limb shortening that was assessed to be unrelated to EFV exposure., Conclusions: The restoration of health and longevity in many HAART-treated women is often accompanied by childbearing, as evidenced by the large fraction of women in our cohort who became pregnant despite their initial statements of intent to avoid pregnancy. Of 22 first-trimester EFV-exposed live births, 1 neonate was found to have a major congenital abnormality; however, this defect was unrelated to EFV exposure. The small sample size is insufficient to estimate accurately the underlying risk of congenital malformation after exposure to EFV in early pregnancy, underscoring the importance of reporting to the existing international Antiretroviral Pregnancy Registry. In addition to accessing safe and effective HAART regimens, HIV-infected women require access to comprehensive family planning services, including contraception and procreation counseling.

Four species of fish from Atlantic waters, Meronia americanus (perch), Cynoscion regalis (seatrout), Micropogon undulatis (croaker) and Pomatomus saltatrix (bluefish), were processed (gutted or filleted), packaged under carbon dioxide and refrigerated. Stability of the fish under the modified atmosphere preservation (MAP) system was compared to that of fish stored conventionally. Use of the MAP system resulted in a 45 to 55% increase in stability, primarily due to an extension in the lag phase of psychrotrophic organisms and to their reduced growth rate in the logarithmic phase. By the 10th day of storage, the conventionally packed fish always exhibited a 100-fold higher psychrotroph count than the CO 2 -packed fish. Levels of Vibrio parahaemolyticus were negligible in this MAP system and no Salmonella spp. or Staphylococcus aureus was detected, even at an abuse temperature (10°C) of storage. Positive evidence for preformed Clostridium botulinum toxin was lacking.