FORWARD AND FALSE STEP TECHNIQUES USED FOR SPRINT START IN A SIDEWAYS DIRECTION: WHICH IS SUPERIOR?

The purpose of this study was to determine which technique is superior to in a standing sprint start in a sideways direction: the false step or forward step technique. Nine males performed 5 m sprints in a rightward direction starting with these two techniques. They took a first step in their right side with their right foot in the forward step trials, whereas they took a first step in their left side with their left foot in the false step trials. No significant differences were found between the two trial conditions in the sprint times for 1 m, 2 m, 3 m and 4 m. These results indicate that the start techniques made no difference in the performance in the sideways direction, although the superiority of the false step technique for the forward sprint start was reported previously. This finding suggests that the superiority of the sprint start techniques is dependent on the sprint direction

EFFECT OF DIFFERENT TRACK START POSITiONS ON HORIZONTAL TAKE-OFF VELOCITY OF WHOLE-SODY CENTER OF MASS IN SWIMMING: A SlMUALTION STUDY

The objective of this study was to investigate the effects of different track start positions on horizontal take-off velocity of the whole-body center of mass (COM) in swimming. The whole body was modeled as linked rigid-body segments to simulate the track start performance, and a simulation was performce with two different track start positions, with the COM positioned at the rear and low level (RL), and at the front and high level (FH). The results demonstrated that the horizontal take-off velocity was faster for the RL than the FH. The hip joint moments were larger for the RL than the FH on both front and rear legs. Therefore, the COM positioned at the rear and lower level for the track start would contribute to a greater hip joint moment generation, producing a greater horizontal velocity of the COM at take-off

Multidendritic sensory neurons in the adult Drosophila abdomen: origins, dendritic morphology, and segment- and age-dependent programmed cell death

<p>Abstract</p> <p>Background</p> <p>For the establishment of functional neural circuits that support a wide range of animal behaviors, initial circuits formed in early development have to be reorganized. One way to achieve this is local remodeling of the circuitry hardwiring. To genetically investigate the underlying mechanisms of this remodeling, one model system employs a major group of <it>Drosophila </it>multidendritic sensory neurons - the dendritic arborization (da) neurons - which exhibit dramatic dendritic pruning and subsequent growth during metamorphosis. The 15 da neurons are identified in each larval abdominal hemisegment and are classified into four categories - classes I to IV - in order of increasing size of their receptive fields and/or arbor complexity at the mature larval stage. Our knowledge regarding the anatomy and developmental basis of adult da neurons is still fragmentary.</p> <p>Results</p> <p>We identified multidendritic neurons in the adult <it>Drosophila </it>abdomen, visualized the dendritic arbors of the individual neurons, and traced the origins of those cells back to the larval stage. There were six da neurons in abdominal hemisegment 3 or 4 (A3/4) of the pharate adult and the adult just after eclosion, five of which were persistent larval da neurons. We quantitatively analyzed dendritic arbors of three of the six adult neurons and examined expression in the pharate adult of key transcription factors that result in the larval class-selective dendritic morphologies. The 'baseline design' of A3/4 in the adult was further modified in a segment-dependent and age-dependent manner. One of our notable findings is that a larval class I neuron, ddaE, completed dendritic remodeling in A2 to A4 and then underwent caspase-dependent cell death within 1 week after eclosion, while homologous neurons in A5 and in more posterior segments degenerated at pupal stages. Another finding is that the dendritic arbor of a class IV neuron, v'ada, was immediately reshaped during post-eclosion growth. It exhibited prominent radial-to-lattice transformation in 1-day-old adults, and the resultant lattice-shaped arbor persisted throughout adult life.</p> <p>Conclusion</p> <p>Our study provides the basis on which we can investigate the genetic programs controlling dendritic remodeling and programmed cell death of adult neurons, and the life-long maintenance of dendritic arbors.</p

Large scale genotyping study for asthma in the Japanese population

<p>Abstract</p> <p>Background</p> <p>Asthma is a complex phenotype that is influenced by both genetic and environmental factors. Genome-wide linkage and association studies have been performed to identify susceptibility genes for asthma. These studies identified new genes and pathways implicated in this disease, many of which were previously unknown.</p> <p>Objective</p> <p>To perform a large-scale genotyping study to identify asthma-susceptibility genes in the Japanese population.</p> <p>Methods</p> <p>We performed a large-scale, three-stage association study on 288 atopic asthmatics and 1032 controls, by using multiplex PCR-Invader assay methods at 82,935 single nucleotide polymorphisms (SNPs) (1^ststage). SNPs that were strongly associated with asthma were further genotyped in samples from asthmatic families (216 families, 762 members, 2^ndstage), 541 independent patients, and 744 controls (3^rdstage).</p> <p>Results</p> <p>SNPs located in the 5' region of <it>PEX19 </it>(rs2820421) were significantly associated with <it>P </it>< 0.05 through the 1^stto the 3^rdstage analyses; however, the <it>P </it>values did not reach statistically significant levels (combined, <it>P </it>= 3.8 × 10^-5; statistically significant levels with Bonferroni correction, <it>P </it>= 6.57 × 10^-7). SNPs on <it>HPCAL1 </it>(rs3771140) and on <it>IL18R1 </it>(rs3213733) were associated with asthma in the 1^stand 2^ndstage analyses, but the associations were not observed in the 3^rdstage analysis.</p> <p>Conclusion</p> <p>No association attained genome-wide significance, but several loci for possible association emerged. Future studies are required to validate these results for the prevention and treatment of asthma.</p

Immunological profile in a family with nephrogenic diabetes insipidus with a novel 11 kb deletion in AVPR2 and ARHGAP4 genes

<p>Abstract</p> <p>Background</p> <p>Congenital nephrogenic diabetes insipidus (NDI) is characterised by an inability to concentrate urine despite normal or elevated plasma levels of the antidiuretic hormone arginine vasopressin. We report a Japanese extended family with NDI caused by an 11.2-kb deletion that includes the entire <it>AVPR2 </it>locus and approximately half of the <it>Rho GTPase-activating protein 4 </it>(<it>ARHGAP4</it>) locus. ARHGAP4 belongs to the RhoGAP family, Rho GTPases are critical regulators of many cellular activities, such as motility and proliferation which enhances intrinsic GTPase activity.</p> <p>ARHGAP4 is expressed at high levels in hematopoietic cells, and it has been reported that an NDI patient lacking <it>AVPR2 </it>and all of <it>ARHGAP4 </it>showed immunodeficiency characterised by a marked reduction in the number of circulating CD3+ cells and almost complete absence of CD8+ cells.</p> <p>Methods</p> <p>PCR and sequencing were performed to identify the deleted region in the Japanese NDI patients. Immunological profiles of the NDI patients were analysed by flow cytometry. We also investigated the gene expression profiles of peripheral blood mononuclear cells (PBMC) from NDI patients and healthy controls in microarray technique.</p> <p>Results</p> <p>We evaluated subjects (one child and two adults) with 11.2-kb deletion that includes the entire <it>AVPR2 </it>locus and approximately half of the <it>ARHGAP4</it>. Hematologic tests showed a reduction of CD4+ cells in one adult patient, a reduction in CD8+ cells in the paediatric patient, and a slight reduction in the serum IgG levels in the adult patients, but none of them showed susceptibility to infection. Gene expression profiling of PBMC lacking <it>ARHGAP4 </it>revealed that expression of RhoGAP family genes was not influenced greatly by the lack of <it>ARHGAP4</it>.</p> <p>Conclusion</p> <p>These results suggest that loss of <it>ARHGAP4 </it>expression is not compensated for by other family members. ARHGAP4 may play some role in lymphocyte differentiation but partial loss of <it>ARHGAP4 </it>does not result in clinical immunodeficiency.</p

The whole blood transcriptional regulation landscape in 465 COVID-19 infected samples from Japan COVID-19 Task Force

「コロナ制圧タスクフォース」COVID-19患者由来の血液細胞における遺伝子発現の網羅的解析 --重症度に応じた遺伝子発現の変化には、ヒトゲノム配列の個人差が影響する--. 京都大学プレスリリース. 2022-08-23.Coronavirus disease 2019 (COVID-19) is a recently-emerged infectious disease that has caused millions of deaths, where comprehensive understanding of disease mechanisms is still unestablished. In particular, studies of gene expression dynamics and regulation landscape in COVID-19 infected individuals are limited. Here, we report on a thorough analysis of whole blood RNA-seq data from 465 genotyped samples from the Japan COVID-19 Task Force, including 359 severe and 106 non-severe COVID-19 cases. We discover 1169 putative causal expression quantitative trait loci (eQTLs) including 34 possible colocalizations with biobank fine-mapping results of hematopoietic traits in a Japanese population, 1549 putative causal splice QTLs (sQTLs; e.g. two independent sQTLs at TOR1AIP1), as well as biologically interpretable trans-eQTL examples (e.g., REST and STING1), all fine-mapped at single variant resolution. We perform differential gene expression analysis to elucidate 198 genes with increased expression in severe COVID-19 cases and enriched for innate immune-related functions. Finally, we evaluate the limited but non-zero effect of COVID-19 phenotype on eQTL discovery, and highlight the presence of COVID-19 severity-interaction eQTLs (ieQTLs; e.g., CLEC4C and MYBL2). Our study provides a comprehensive catalog of whole blood regulatory variants in Japanese, as well as a reference for transcriptional landscapes in response to COVID-19 infection

DOCK2 is involved in the host genetics and biology of severe COVID-19

「コロナ制圧タスクフォース」COVID-19疾患感受性遺伝子DOCK2の重症化機序を解明 --アジア最大のバイオレポジトリーでCOVID-19の治療標的を発見--. 京都大学プレスリリース. 2022-08-10.Identifying the host genetic factors underlying severe COVID-19 is an emerging challenge. Here we conducted a genome-wide association study (GWAS) involving 2, 393 cases of COVID-19 in a cohort of Japanese individuals collected during the initial waves of the pandemic, with 3, 289 unaffected controls. We identified a variant on chromosome 5 at 5q35 (rs60200309-A), close to the dedicator of cytokinesis 2 gene (DOCK2), which was associated with severe COVID-19 in patients less than 65 years of age. This risk allele was prevalent in East Asian individuals but rare in Europeans, highlighting the value of genome-wide association studies in non-European populations. RNA-sequencing analysis of 473 bulk peripheral blood samples identified decreased expression of DOCK2 associated with the risk allele in these younger patients. DOCK2 expression was suppressed in patients with severe cases of COVID-19. Single-cell RNA-sequencing analysis (n = 61 individuals) identified cell-type-specific downregulation of DOCK2 and a COVID-19-specific decreasing effect of the risk allele on DOCK2 expression in non-classical monocytes. Immunohistochemistry of lung specimens from patients with severe COVID-19 pneumonia showed suppressed DOCK2 expression. Moreover, inhibition of DOCK2 function with CPYPP increased the severity of pneumonia in a Syrian hamster model of SARS-CoV-2 infection, characterized by weight loss, lung oedema, enhanced viral loads, impaired macrophage recruitment and dysregulated type I interferon responses. We conclude that DOCK2 has an important role in the host immune response to SARS-CoV-2 infection and the development of severe COVID-19, and could be further explored as a potential biomarker and/or therapeutic target