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As the adoption and scope of genetic testing continue to expand, interpreting the clinical significance of DNA sequence variants at scale remains a formidable challenge, with a high proportion classified as variants of uncertain significance (VUSs). Genetic testing laboratories have historically relied, in part, on functional data from academic literature to support variant classification. High-throughput functional assays or multiplex assays of variant effect (MAVEs), designed to assess the effects of DNA variants on protein stability and function, represent an important and increasingly available source of evidence for variant classification, but their potential is just beginning to be realized in clinical lab settings. Here, we describe a framework for generating, validating and incorporating data from MAVEs into a semi-quantitative variant classification method applied to clinical genetic testing. Using single-cell gene expression measurements, cellular evidence models were built to assess the effects of DNA variation in 44 genes of clinical interest. This framework was also applied to models for an additional 22 genes with previously published MAVE datasets. In total, modeling data was incorporated from 24 genes into our variant classification method. These data contributed evidence for classifying 4043 observed variants in over 57,000 individuals. Genetic testing laboratories are uniquely positioned to generate, analyze, validate, and incorporate evidence from high-throughput functional data and ultimately enable the use of these data to provide definitive clinical variant classifications for more patients. [ABSTRACT FROM AUTHOR]

Viviparous rockfishes (Sebastes spp., family Scorpaenidae) mate and store sperm in the ovaries for several months prior to fertilization, as oocytes develop for the parturition season. Although multiple paternity has been documented in single‐brooding rockfishes, paternity in consecutive broods of multiple‐brooding species has not been studied. Analyses of multilocus microsatellite genotypes in both residual larvae left in the ovary from a previous parturition and upcoming fertilized broods in the same ovary demonstrated evidence of the same sires in consecutive broods in chilipepper (Sebastes goodei) and speckled (Sebastes ovalis) rockfishes. One S. goodei mother showed evidence of multiple paternity from the same two sires in both consecutive broods. The ability to retain sperm, even after a parturition event, for use in subsequent broods, confers an advantage to ensure fertilization and allows for extension of the parturition season. This life‐history strategy provides a bet‐hedging advantage in the California Current system, an environmentally dynamic ecosystem where larval survivorship and subsequent recruitment to adult populations can vary temporally by orders of magnitude. [ABSTRACT FROM AUTHOR]

Successful reproduction is critical to the growth and persistence of marine fish populations, yet how changes in the environment influence reproduction remains largely unknown. We explored how shifting ocean conditions influenced larval production in four species of long-lived, live-bearing rockfish (Sebastes spp.) in the California Current. Brood fecundity, body size, and environmental information were analyzed from the mid-1980s through 2020. Interannual variation in brood fecundity was greater than 50% in the single-brooding yellowtail rockfish (S. flavidus) and widow rockfish (S. entomelas). Brood fecundity varied less in chilipepper (S. goodei) and bocaccio (S. paucispinis), two species capable of multiple broods per year. In these two species, interannual fecundity variability is more likely to depend on the number of broods produced than on brood size alone. In all four species, brood fecundity was positively correlated with maternal length and body condition. Variable ocean conditions influenced the strength of maternal size effects by year. These results provide evidence for reproductive plasticity and environmental effects on fecundity, with implications for changes in population reproductive potential with climate change. [ABSTRACT FROM AUTHOR]

This article recounts the author's experience as a junior diplomat in the British Diplomatic Service in the late 1960s handling the file of Rudolf Hess, Hitler's ex-deputy serving a life sentence in Spandau prison in Berlin. As the only Nazi leader still imprisoned there after the release in 1966 of Albert Speer and Baldur von Schirach, his fate as 'the lone prisoner of Spandau'had become an international issue. Sentenced at the Nuremberg trial of 1946, his fate was a matter for the four powers still occupying Berlin. Moscow was determined that as the last remaining symbol of the Hitler regime Hess should die there. In the West, however, and especially in Britain, there was a press campaign for his release that put pressure on the Foreign Office by way of letters from the public and parliamentary questions. As a desk officer for Germany, it fell to me to handle this by writing or drafting replies to the effect that as Hess was a prisoner of all four powers the decision required consent, that Moscow was adamantly opposed, and that Britain could not act unilaterally. But the real target of the press campaign, spearheaded by the Beaverbrook press through the Daily and Sunday Express, was Harold Wilson's Labour Government. Anything that could demonstrate his alleged 'appeasement' of Moscow was grist to its mill. The now weeded file in the National Archives gives little hint of this politically-motivated agenda. [ABSTRACT FROM AUTHOR]

To define a complete catalog of the genes that are activated during mouse sclerotome formation, we sequenced RNA from embryonic mouse tissue directed to form sclerotome in culture. In addition to well-known early markers of sclerotome, such as Pax1, Pax9, and the Bapx2/Nkx3-2 homolog Nkx3-1, the long-noncoding RNA PEAT (Pax1 enhancer antisense transcript) was induced in sclerotome-directed samples. Strikingly, PEAT is located just upstream of the Pax1 gene. Using CRISPR/Cas9, we generated a mouse line bearing a complete deletion of the PEAT-transcribed unit. RNA-seq on PEAT mutant embryos showed that loss of PEAT modestly increases bone morphogenetic protein target gene expression and also elevates the expression of a large subset of ribosomal protein mRNAs. [ABSTRACT FROM AUTHOR]

Highlights: [•] Loss of Follistatin enhances Noggin mutant axial skeleton defects. [•] In Noggin mutants, Follistatin aids in maintaining proper somite size. [•] Follistatin affects somite size following somite formation. [•] Follistatin limits BMP-mediated lateralization of paraxial mesoderm. [•] Noggin and Gremlin1 mutation does not reduce somitic Follistatin activation. [Copyright &y& Elsevier]

Sustainable and conventional farming systems use fertilizers that differ in the availability of nitrogen, which may affect plant quality to alter the abundance and performance of potential pest species., We grew brassica plants in several types of fertilizer, including those commonly used in conventional and sustainable farming systems, and an unfertilized control. The effects of fertilizer type on the performance of two aphid species and foliar glucosinolate content were investigated., Both aphid species performed poorly (with reduced fecundity) on the unfertilized treatment compared with those feeding on fertilized host plants., Brevicoryne brassicae, the brassica specialist, performed best on Brassica oleracea plants fertilized with an organic animal manure, with a 72% increase in fecundity and an 18% increase in intrinsic rate of increase compared with plants fertilized with ammonium nitrate., By contrast, the generalist Myzus persicae had an intrinsic rate of increase that was reduced by 15% on plants growing in the animal manure compared with those growing in ammonium nitrate., These results may explain earlier findings on the effects of fertilizer type on aphid populations in the field, and are discussed in the context of pest species' responses to sustainable and conventional agricultural systems. [ABSTRACT FROM AUTHOR]

Abstract: Toluene is a commonly abused solvent found in many industrial and commercial products. The neurobiological effects of toluene remain unclear, but many of them, like those of ethanol, may be mediated by γ-aminobutyric acid (GABA) and glutamate receptors. Chronic ethanol administration has been shown to alter levels of specific subunits for GABA type A (GABAA), N-methyl-d-aspartate (NMDA) and α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA) receptors. However, little is known about the effects of toluene on subunit levels of these receptors. To examine this, rats were exposed to toluene vapors (8000ppm) or air for 10 days (30min/day), and afterwards GABAA α1, NR1 and NR2B (NMDA) and GluR1 and GluR2/3 (AMPA) receptor subunit levels were determined in discrete brain regions of these animals by Western blotting. Toluene increased GABAA α1, NR1, NR2B and GluR2/3 subunits in the medial prefrontal cortex and decreased GABAA α1 and NR1 subunits in the substantia nigra compacta. Toluene inhalation produced modest increases in GABAA α1 subunits in the striatum, as well as slight decreases in this subunit in the ventral tegmental area. NR2B subunit levels were also slightly increased within the nucleus accumbens by toluene. These studies show that toluene differentially alters the levels of specific GABAergic and glutamatergic receptor subunits in a regionally selective manner. [Copyright &y& Elsevier]

The effects of two anorectic drugs, dexfenfluramine and phentermine, on food intake under different food-access conditions were examined. Experiment 1 compared the effects of these drugs on food intake under a progressive-ratio (PR) schedule and free-access conditions. Dexfenfluramine decreased food intake under both conditions, but the doses required to decrease intake under free-access conditions were higher than those required to reduce intake trader the PR condition. Inter mediate doses of phentermine sometimes increased breaking points, and higher doses decreased them. Phentermine decreased food intake at the same doses under both access conditions. Thus the potency of dexfenfluramine, but not phentermine, to decrease food-maintained behavior depended upon the food access condition. Experiment 2 used a novel mixed progressive-ratio schedule of food delivery to study the duration of drug effects. Sessions consisted of five components separated by 3-hr timeouts. The ratio requirement reset at the beginning of each component and a new breaking point was obtained. Both dexfenfluramine and phentermine dose-dependently decreased breaking points early in the session. In some rats, compensatory increases in breaking point were observed. That is, breaking points later in the session increased over control levels, resulting in no change in the total number of food pellets earned for the session compared to control. The present findings suggest that the effects of some anorectic drugs depend upon the access conditions for food; increasing the effort to obtain food may enhance their ability to decrease food-maintained behavior. [ABSTRACT FROM AUTHOR]

The mechanisms that subdivide the endoderm into the discrete primordia that give rise to organs such as the pancreas and liver are not well understood. However, it is known that retinoic acid (RA) signaling is critical for regionalization of the vertebrate embryo: when RA signaling is either prevented or augmented, anteroposterior (AP) patterning of the CNS and mesoderm is altered and major developmental defects occur . We have investigated the role of RA signaling in regionalization of the zebrafish endoderm. Using a mutant that prevents RA synthesis and an antagonist of the RA receptors , we show that specification of both the pancreas and liver requires RA signaling. By contrast, RA signaling is not required for the formation of the endodermal germ layer or for differentiation of other endodermal organs. Timed antagonist and RA treatments show that the RA-dependent step in pancreatic specification occurs at the end of gastrulation, significantly earlier than the expression of known markers of pancreatic progenitors. In addition to being required for pancreatic specification, RA has the capacity to transfate anterior endoderm to a pancreatic fate. [Copyright &y& Elsevier]

Abstract Rationale: Previous reports suggest that propofol (PPF) may have abuse potential in humans. Hence, we hypothesized that PPF could reinforce sell-administration behavior in other species. Positive reinforcing effects of PPF could be interpreted as an index of abuse liability. Objective: Acquisition and maintenance of i.v. PPF self-administration were examined in 12 rats. Methods: Six rats were initially given access to methohexital (MHX, 2.0 mg/kg per infusion) under a fixed ratio (FR) 1 schedule, while the other six were initially given access to PPF (1.7 mg/kg per infusion). Once stable responding was established, various doses of PPF (0.56, 1.0, and 1.7 mg/kg per infusion) and vehicle (Intralipid 20%) were made available. Results: The number of PPF infusions per session was an inverse function of dose, with 0.56 mg/kg and 1.0 mg/kg per infusion maintaining significantly more infusions per session than vehicle in most rats under the FR 1 schedule. For some rats, the number of vehicle infusions per session was equal to or greater than the number of PPF infusions. Increasing the response requirement to FR 5 decreased the number of vehicle infusions per session in these rats, while PPF maintained a higher number of infusions than vehicle under this FR value in six of seven rats. Conclusion: PPF served as a reinforcer in rats under FR schedules of i.v. drug delivery, adding to the extant evidence that it has abuse potential. [ABSTRACT FROM AUTHOR]

Introduces a series of articles related to intelligence relations of the U.S., Canada and Great Britain from 1939 through 2000.

Deals with a study which recognized the roles of war leaders Sir Winston Churchill and Franklin Roosevelt in the secret war against ally countries Germany and Japan during World War II. Contributions of Churchill to British intelligence in World War I; Admiration of Roosevelt for Britiish intelligence; Purpose of nightime visit to Henry Morgenthau Jr., secretary of the U.S. Treasury.

Abstract Drugs, like other reinforcers, can vary in their relative abilities to support operant responding. Considerable research has been designed to obtain useful measures of a given drug's or dose's "reinforcing efficacy" and to identify the ways in which a variety of behavioral and pharmacological variables impact these measures. Progressive-ratio schedules of drug delivery generate an index of a drug's or dose's reinforcing efficacy (the breaking point) and are being used increasingly as tools in the analysis of drug self-administration. Progressive-ratio schedules of drug delivery have been used to characterize the effects of pretreatment drugs, lesions, drug deprivation, physical dependence, and repeated non-contingent drug exposure on breaking points. Behavioral factors, including food restriction and electric shock, and organismic factors, including gender and strain, have also been investigated using progressive-ratio schedules of drug delivery. To the extent that breaking points provide an index of reinforcing efficacy, these studies demonstrate that a wide range of variables can influence the reinforcing efficacy of self-administered drugs. The objectives of this review are to critique existing research themes, outline potential limitations of progressive-ratio procedures, and to suggest potentially fruitful uses of these procedures in future research. [ABSTRACT FROM AUTHOR]

Presents a study which examined the effects of step size and break-point criterion on the progressive-ratio performance of pigeons. How key pecking by pigeons was maintained; Information on progressive-ratio schedules of food delivery in pigeons; Details on the experiments conducted on the pigeons; Factors which influence pigeons pecking behavior; Results of this study.

Forecasts from climate models and oceanographic observations indicate increasing deoxygenation in the global oceans and an elevated frequency and intensity of hypoxic events in the coastal zone, which have the potential to affect marine biodiversity and fisheries. Exposure to low dissolved oxygen (DO) conditions may have deleterious effects on early life stages in fishes. This study aims to identify thresholds to hypoxia while testing behavioral and physiological responses of two congeneric species of kelp forest fish to four DO levels, ranging from normoxic to hypoxic (8.7, 6.0, 4.1, and 2.2 mg O2/L). Behavioral tests identified changes in exploratory behavior and turning bias (lateralization), whereas physiological tests focused on determining changes in hypoxia tolerance (pCrit), ventilation rates, and metabolic rates, with impacts on the resulting capacity for aerobic activity. Our findings indicated that copper rockfish (Sebastes caurinus) and blue rockfish (Sebastes mystinus) express sensitivity to hypoxia; however, the strength of the response differed between species. Copper rockfish exhibited reduced absolute lateralization and increased escape time at the lowest DO levels, whereas behavioral metrics for blue rockfish did not vary with oxygen level. Both species exhibited decreases in aerobic scope (as a function of reduced maximum metabolic rate) and increases in ventilation rates to compensate for decreasing oxygen levels. Blue rockfish had a lower pCrit and stronger acclimation response compared to copper rockfish. The differences expressed by each species suggest that acclimatization to changing ocean conditions may vary, even among related species that recruit to the same kelp forest habitat, leading to winners and losers under future ocean conditions. Exposure to hypoxia can decrease individual physiological fitness through metabolic and aerobic depression and changes to anti‐predator behavior, with implications for the outcome of ecological interactions and the management of fish stocks in the face of climate change. [ABSTRACT FROM AUTHOR]

An understanding of the reproductive biology of a species is fundamental to successful management of fish stocks. Rockfish ( Sebastes spp.) have complex reproduction, being viviparous and generally late to mature, often with extended adolescent periods characterized by abortive maturation events. Furthermore, whereas the majority of Sebastes species in the California Current region produce one brood of larvae annually, several are known to produce more than one, though no stock assessments have yet considered the impact multiple brooding may have on population spawning potential for these species. We documented abortive maturation and examined the prevalence and size-dependent and regional patterns of multiple brooding using macroscopic evaluation and detailed histological analysis of ovaries from a model species, chilipepper ( S. goodei ), collected off Central and Southern California. We modeled the size-related maternal effect on the probability of multiple brooding, and quantified size-dependent fecundity relationships. Our results indicate that the most robust estimation of reproductive output, as a function of the fecundity-length relationship, is improved for chilipepper when multiple brooding is incorporated, due to the greater probability of additional broods, and thus greater spawning potential, in larger females. [ABSTRACT FROM AUTHOR]

Inductive signals from adjacent tissues initiate differentiation within the somite. In this study, we used mouse embryos mutant for the BMP antagonists noggin (Nog) and gremlin 1 (Grem1) to characterize the effects of BMP signaling on the specification of the sclerotome. We confirmed reduction of Pax1 and Pax9 expression in Nog mutants, but found that Nog;Grem1 double mutants completely fail to initiate sclerotome development. Furthermore, Nog mutants that also lack one allele of Grem1 exhibit a dramatic reduction in axial skeleton relative to animals mutant for Nog alone. By contrast, Pax3, Myf5 and Lbx1 expression indicates that dermomyotome induction occurs in Nog;Grem1 double mutants. Neither conditional Bmpr1a mutation nor treatment with the BMP type I receptor inhibitor dorsomorphin expands sclerotome marker expression, suggesting that BMP antagonists do not have an instructive function in sclerotome specification. Instead, we hypothesize that Nog- and Grem1-mediated inhibition of BMP is permissive for hedgehog (Hh) signal-mediated sclerotome specification. In support of this model, we found that culturing Nog;Grem1 double-mutant embryos with dorsomorphin restores sclerotome, whereas Pax1 expression in smoothened (Smo) mutants is not rescued, suggesting that inhibition of BMP is insufficient to induce sclerotome in the absence of Hh signaling. Confirming the dominant inhibitory effect of BMP signaling, Pax1 expression cannot be rescued in Nog;Grem1 double mutants by forced activation of Smo. We conclude that Nog and Grem1 cooperate to maintain a BMP signaling-free zone that is a crucial prerequisite for Hh-mediated sclerotome induction. [ABSTRACT FROM AUTHOR]

During vertebrate development, the endodermal germ layer becomes regionalized along its anteroposterior axis to give rise to a variety of organs, including the pancreas. Genetic studies in zebrafish and mice have established that the signaling molecule retinoic acid (RA) plays a crucial role in endoderm patterning and promotes pancreas development. To identify how RA signals to pancreatic progenitors in the endoderm, we have developed a novel cell transplantation technique, using the ability of the SOX32 transcription factor to confer endodermal identity, to selectively target reagents to (or exclude them from) the endodermal germ layer of the zebrafish. We show that RA synthesized in the anterior paraxial mesoderm adjacent to the foregut is necessary for the development of insulin-expressing {beta}-cells. Conversely, RA receptor function is required in the foregut endoderm for insulin expression, but not in mesoderm or ectoderm. We further show that activation of RA signal transduction in endoderm alone is sufficient to induce insulin expression. Our results reveal that RA is an instructive signal from the mesoderm that directly induces precursors of the endocrine pancreas. These findings suggest that RA will have important applications in the quest to induce islets from stem cells for therapeutic uses. [ABSTRACT FROM AUTHOR]

A warming climate poses a fundamental problem for embryos that develop within eggs because their demand for oxygen (O2) increases much more rapidly with temperature than their capacity for supply, which is constrained by diffusion across the egg surface. Thus, as temperatures rise, eggs may experience O2 limitation due to an imbalance between O2 supply and demand. Here, we formulate a mathematical model of O2 limitation and experimentally test whether this mechanism underlies the upper thermal tolerance in large aquatic eggs. Using Chinook salmon (Oncorhynchus tshawytscha) as a model system, we show that the thermal tolerance of eggs varies systematically with features of the organism and environment. Importantly, this variation can be precisely predicted by the degree to which these features shift the balance between O2 supply and demand. Equipped with this mechanistic understanding, we predict and experimentally confirm that the thermal tolerance of these embryos in their natural habitat is substantially lower than expected from laboratory experiments performed under normoxia. More broadly, our biophysical model of O2 limitation provides a mechanistic explanation for the elevated thermal sensitivity of fish embryos relative to other life stages, global patterns in egg size and the extreme fecundity of large teleosts. [ABSTRACT FROM AUTHOR]

Climate change is predicted to alter ocean chemistry through warming temperatures, increases in CO 2 (i.e., ocean acidification), and reductions in dissolved oxygen (DO) (i.e., hypoxia). Past research has shown that early life stages of marine fishes are sensitive to all three stressors, but with sometimes different directions of response. In this study, we examined the separate effects of ocean acidification and hypoxia on otolith growth in two species of juvenile rockfish (copper rockfish, Sebastes caurinus , and blue rockfish, Sebastes mystinus). Fishes were collected at settlement stage from kelp forests on the central California coast and reared in the laboratory for up to 6 months in 4 separate pH treatments (pH = 7.3, 7.6, 7.8, and a control of 8.0), simulating the effects of ocean acidification through the addition of CO 2 , and 4 separate dissolved oxygen treatments (DO = 2.2, 4.1, 6.0, and a control of 8.7 mg/L), simulating the effects of hypoxia. For both species, otoliths were smaller for a given fish length in response to hypoxia but were larger (trend was non-significant for copper rockfish) in response to elevated CO 2. The results suggest that otolith growth may respond differently to ocean acidification and hypoxia for some species, which has implications for sensory development, ecological performance, and interpretations of the permanent record of fish growth in hard parts such as otoliths. • Elevated CO 2 and reduced dissolved oxygen have opposite effects on otolith (earstone) development in juvenile copper and blue rockfish. • Increased CO 2 levels resulted in otoliths being larger in area for a relative fish body size in blue rockfish. • Reduced dissolved oxygen levels results in otoliths being smaller in area for a relative fish body size in both species. [ABSTRACT FROM AUTHOR]

The transcriptional mechanisms driving lineage specification during development are still largely unknown, as the interplay of multiple transcription factors makes it difficult to dissect these molecular events. Using a cell-based differentiation platform to probe transcription function, we investigated the role of the key paraxial mesoderm and skeletal myogenic commitment factors—mesogenin 1 (Msgn1), T-box 6 (Tbx6), forkhead box C1 (Foxc1), paired box 3 (Pax3), Paraxis, mesenchyme homeobox 1 (Meox1), sine oculis-related homeobox 1 (Six1), and myogenic factor 5 (Myf5)—in paraxial mesoderm and skeletal myogenesis. From this study, we define a genetic hierarchy, with Pax3 emerging as the gatekeeper between the presomitic mesoderm and the myogenic lineage. By assaying chromatin accessibility, genomic binding and transcription profiling in mesodermal cells from mouse and human Pax3-induced embryonic stem cells and Pax3-null embryonic day (E)9.5 mouse embryos, we identified conserved Pax3 functions in the activation of the skeletal myogenic lineage through modulation of Hedgehog, Notch, and bone morphogenetic protein (BMP) signaling pathways. In addition, we demonstrate that Pax3 molecular function involves chromatin remodeling of its bound elements through an increase in chromatin accessibility and cooperation with sine oculis-related homeobox 4 (Six4) and TEA domain family member 2 (Tead2) factors. To our knowledge, these data provide the first integrated analysis of Pax3 function, demonstrating its ability to remodel chromatin in mesodermal cells from developing embryos and proving a mechanistic footing for the transcriptional hierarchy driving myogenesis. [ABSTRACT FROM AUTHOR]