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701.
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In a murine model of moderate childhood malnutrition we found that polynutrient deficiency led to a 4–5-fold increase in early visceralization of L. donovani (3 days post-infection) following cutaneous infection and a 16-fold decrease in lymph node barrier function (p<0.04 for all). To begin to understand the mechanistic basis for this malnutrition-related parasite dissemination we analyzed the cellularity, architecture, and function of the skin-draining lymph node. There was no difference in the localization of multiple cell populations in the lymph node of polynutrient deficient (PND) mice, but there was reduced cellularity with fewer CD11c+dendritic cells (DCs), fibroblastic reticular cells (FRCs), MOMA-2+ macrophages, and CD169+ subcapsular sinus macrophage (p<0.05 for all) compared to the well-nourished (WN) mice. The parasites were equally co-localized with DCs associated with the lymph node conduit network in the WN and PND mice, and were found in the high endothelial venule into which the conduits drain. When a fluorescent low molecular weight (10 kD) dextran was delivered in the skin, there was greater efflux of the marker from the lymph node conduit system to the spleens of PND mice (p<0.04), indicating that flow through the conduit system was altered. There was no evidence of disruption of the conduit or subcapsular sinus architecture, indicating that the movement of parasites into the subcortical conduit region was due to an active process and not from passive movement through a leaking barrier. These results indicate that the impaired capacity of the lymph node to act as a barrier to dissemination of L. donovani infection is associated with a reduced number of lymph node phagocytes, which most likely leads to reduced capture of parasites as they transit through the sinuses and conduit system.  相似文献   
704.
Professional recommendations for the return of results from exome and whole-genome sequencing (ES/WGS) have been controversial. The lack of clear guidance about whether and, if so, how to return ES/WGS incidental results limits the extent to which individuals and families might benefit from ES/WGS. The perspectives of genetics professionals, particularly those at the forefront of using ES/WGS in clinics, are largely unknown. Data on stakeholder perspectives could help clarify how to weigh expert positions and recommendations. We conducted an online survey of 9,857 genetics professionals to learn their attitudes on the return of incidental results from ES/WGS and the recent American College of Medical Genetic and Genomics Recommendations for Reporting of Incidental Findings in Clinical Exome and Genome Sequencing. Of the 847 respondents, 760 completed the survey. The overwhelming majority of respondents thought that incidental ES/WGS results should be offered to adult patients (85%), healthy adults (75%), and the parents of a child with a medical condition (74%). The majority thought that incidental results about adult-onset conditions (62%) and carrier status (62%) should be offered to the parents of a child with a medical condition. About half thought that offered results should not be limited to those deemed clinically actionable. The vast majority (81%) thought that individual preferences should guide return. Genetics professionals’ perspectives on the return of ES/WGS results differed substantially from current recommendations, underscoring the need to establish clear purpose for recommendations on the return of incidental ES/WGS results as professional societies grapple with developing and updating recommendations.  相似文献   
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Opercular and surfacing activity were observed in the Indian catfish Clarias batrachus and Heteropneustes fossilis. In the series A experiments, the opercular activity was monitored under two experimental conditions, viz., (1) surfacing allowed and (2) surfacing prevented. A statistically significant elevation of the rate of opercular activity was observed when air breathing was prevented in both species. In addition, a significant prevention effect and a time of day dependence of that were noticed in both species. In the series B experiments, temporal patterns of surfacing and air-gulping activities were examined under an artificial LD 12:12 schedule at 2-h intervals over a period of 48 h. The inter air-gulping interval in minutes between two consecutive bouts was also recorded four times each day in both species. A significant 24-h rhythm was found for the rate of surfacing activity and length of the inter air-gulping interval in both species. However, the overall activity appears to be much higher in Heteropneustes fossilis as compared to Clarias batrachus.  相似文献   
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The derivation of the restricted intra-sire regression heritability estimator is provided. Procedures for obtaining a stable estimate of residual error variance σ2 are outlined. A small illustration based on live data is given.  相似文献   
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