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91.
Artificial breeding programmes commonly lead to domestication, which is associated with many behavioural differences that can reduce the success of animals released into natural environments. To better understand the factors contributing to domestication, we used a captive population of Chinook salmon (Oncorhynchus tshawytscha) to partition hormonal and behavioural differences to effects of the breeding method and rearing environment. We compared 9‐mo‐old juveniles from three lines that shared a common genetic background: (1) the Channel line produced by natural spawning and reared in a low‐density environment with a natural substrate for approx. 6 mo before being transferred to the hatchery; (2) the Hatchery line produced by artificial spawning; and (3) the Transfer line produced by natural spawning but reared in the hatchery from the eyed‐egg stage. Plasma concentrations of 11‐ketotestosterone (11‐KT) and cortisol were measured in groups of 150 fish and again after 4 d of social interactions in groups of six fish. There was no difference in 11‐KT among lines in large groups, but in small groups, Transfer fish had lower 11‐KT concentrations and were significantly less aggressive than both Channel and Hatchery fish. Regardless of group size, concentrations of the stress hormone cortisol were nearly twofold higher in Channel fish than in Hatchery and Transfer fish. Furthermore, the elevated cortisol concentrations in Channel fish were associated with 35% lower feeding rates than in the other two lines. Our study details complex behavioural and hormonal responses to breeding method and rearing environment in juvenile salmon.  相似文献   
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93.
Musical aptitude is commonly measured using tasks that involve discrimination of different types of musical auditory stimuli. Performance on such different discrimination tasks correlates positively with each other and with intelligence. However, no study to date has explored these associations using a genetically informative sample to estimate underlying genetic and environmental influences. In the present study, a large sample of Swedish twins (N = 10,500) was used to investigate the genetic architecture of the associations between intelligence and performance on three musical auditory discrimination tasks (rhythm, melody and pitch). Phenotypic correlations between the tasks ranged between 0.23 and 0.42 (Pearson r values). Genetic modelling showed that the covariation between the variables could be explained by shared genetic influences. Neither shared, nor non-shared environment had a significant effect on the associations. Good fit was obtained with a two-factor model where one underlying shared genetic factor explained all the covariation between the musical discrimination tasks and IQ, and a second genetic factor explained variance exclusively shared among the discrimination tasks. The results suggest that positive correlations among musical aptitudes result from both genes with broad effects on cognition, and genes with potentially more specific influences on auditory functions.  相似文献   
94.
BackgroundThe translocation t(15:19) produces the oncogenic BRD4-NUT fusion which is pathognomonic for NUT carcinoma (NC), which is a rare, but extremely aggressive solid tumor. Comprehensive genomic profiling (CGP) by hybrid-capture based next generation sequencing of 186+ genes of a cohort of advanced cancer cases with a variety of initial diagnoses harboring BRD4-NUT may shed further insight into the biology of these tumors and possible options for targeted treatment.Case presentationThirty-one solid tumor cases harboring a BRD4-NUT translocation are described, with only 16% initially diagnosed as NC and the remainder carrying other diagnoses, most commonly NSCLC—NOS (22%) and lung squamous cell carcinoma (NSCLC-SCC) (16%). The cohort was all microsatellite stable and harbored a low Tumor Mutational Burden (TMB, mean 1.7 mut/mb, range 0–4). In two index cases, patients treated with immune checkpoint inhibitors (ICPI) had unexpected partial or better responses of varying duration. Notably, four cases – including the two index cases - were negative for PD-L1 expression. Neo-antigen prediction for BRD4-NUT and then affinity modeling of the peptide-MHC (pMHC) complex for an assessable index case predicted very high affinity binding, both on a ranked (99.9%) and absolute (33 nM) basis.ConclusionsCGP identifies BRD4-NUT fusions in advanced solid tumors which carry a broad range of initial diagnoses and which should be re-diagnosed as NC per guidelines. A hypothesized mechanism underlying responses to ICPI in the low TMB, PD-L1 negative index cases is the predicted high affinity of the BRD4-NUT fusion peptide to MHC complexes. Further study of pMHC affinity and response to immune checkpoint inhibitors in patients with NC harboring BRD4-NUT is needed to validate this therapeutic hypothesis.  相似文献   
95.
Many research studies use immortalized cell lines as surrogates for primary beta- cells. We describe the production and use of a novel "indirect" dual-fluorescent reporter system that leads to mutually exclusive expression of EGFP in insulin-producing (INS(+)) beta-cells or mCherry in non-beta-cells. Our system uses the human insulin promoter to initiate a Cre-mediated shift in reporter color within a single transgene construct and is useful for FACS selection of cells from single cultures for further analysis. Application of our reporter to presumably clonal HIT-T15 insulinoma cells, as well as other presumably clonal lines, indicates that these cultures are in fact heterogeneous with respect to INS(+) phenotype. Our strategy could be easily applied to other cell- or tissue-specific promoters. We anticipate its utility for FACS purification of INS(+) and glucose-responsive beta-like-cells from primary human islet cell isolates or in vitro differentiated pluripotent stem cells.  相似文献   
96.
Abnormal T cell responses to commensal bacteria are involved in the pathogenesis of inflammatory bowel disease. MyD88 is an essential signal transducer for TLRs in response to the microflora. We hypothesized that TLR signaling via MyD88 was important for effector T cell responses in the intestine. TLR expression on murine T cells was examined by flow cytometry. CD4(+)CD45Rb(high) T cells and/or CD4(+)CD45Rb(low)CD25(+) regulatory T cells were isolated and adoptively transferred to RAG1(-/-) mice. Colitis was assessed by changes in body weight and histology score. Cytokine production was assessed by ELISA. In vitro proliferation of T cells was assessed by [(3)H]thymidine assay. In vivo proliferation of T cells was assessed by BrdU and CFSE labeling. CD4(+)CD45Rb(high) T cells expressed TLR2, TLR4, TLR9, and TLR3, and TLR ligands could act as costimulatory molecules. MyD88(-/-) CD4(+) T cells showed decreased proliferation compared with WT CD4(+) T cells both in vivo and in vitro. CD4(+)CD45Rb(high) T cells from MyD88(-/-) mice did not induce wasting disease when transferred into RAG1(-/-) recipients. Lamina propria CD4(+) T cell expression of IL-2 and IL-17 and colonic expression of IL-6 and IL-23 were significantly lower in mice receiving MyD88(-/-) cells than mice receiving WT cells. In vitro, MyD88(-/-) T cells were blunted in their ability to secrete IL-17 but not IFN-gamma. Absence of MyD88 in CD4(+)CD45Rb(high) cells results in defective T cell function, especially Th17 differentiation. These results suggest a role for TLR signaling by T cells in the development of inflammatory bowel disease.  相似文献   
97.
The diagnosis and species composition of Bilobia Cooper, 1956 (family Leptestiidae, Strophomenida, Brachiopoda) are specified based on literary data and collection from the Leningrad Region. In particular, the cardinal process with cleft shaft and trifid myophore and denticles along the area of ventral valve are adduced to the diagnosis. A new species, B. alichovae sp. nov., from the Sandbian Stage of the Leningrad Region is established.  相似文献   
98.
99.
Regulation of DNA replication and copy number is necessary to promote genome stability and maintain cell and tissue function. DNA replication is regulated temporally in a process known as replication timing (RT). Rap1-interacting factor 1 (Rif1) is a key regulator of RT and has a critical function in copy number control in polyploid cells. Previously, we demonstrated that Rif1 functions with SUUR to inhibit replication fork progression and promote underreplication (UR) of specific genomic regions. How Rif1-dependent control of RT factors into its ability to promote UR is unknown. By applying a computational approach to measure RT in Drosophila polyploid cells, we show that SUUR and Rif1 have differential roles in controlling UR and RT. Our findings reveal that Rif1 acts to promote late replication, which is necessary for SUUR-dependent underreplication. Our work provides new insight into the process of UR and its links to RT.  相似文献   
100.
We have identified a heptapeptide with high affinity to rheumatoid arthritis-associated class II major histocompatibility (MHC) molecules. Using a model of its interaction with the class II binding site, a variety of mimetic substitutions were introduced into the peptide. Several unnatural amino acids and dipeptide mimetics were found to be appropriate substituents and could be combined into compounds with binding affinities comparable to that of the original peptide. Compounds were designed that were several hundred-fold to more than a thousand-fold more potent than the original peptide in inhibiting T-cell responses to processed protein antigens presented by the target MHC molecules. Peptidomimetic compounds of this type could find therapeutic use as MHC-selective antagonists of antigen presentation in the treatment of autoimmune diseases.  相似文献   
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