98 research outputs found
A male-killing Wolbachia carries a feminizing factor and is associated with degradation of the sex-determining system of its host
Endosymbiotic bacteria of the genus Wolbachia induce diverse reproductive alterations in their insect hosts. Wolbachia (wSca) infecting the moth Ostrinia scapulalis causes unusual male killing, in which males (genotype: ZZ) selectively die during embryonic and larval development, whereas females (genotype: ZW), in turn, selectively die when cured of infection. To gain insight into the interaction between wSca and the host, we analysed phenotypic and genetic sexes of the embryos and larvae of normal, wSca-infected, and infected-and-cured O. scapulalis by diagnosing the sex-specifically spliced transcripts of Osdsx—a homologue of the sex-determining gene doublesex—and sex chromatin in interphase nuclei, respectively. It was observed that the female-type Osdsx was expressed in the infected male (ZZ) progenies destined to die, whereas the male-type Osdsx was expressed in the cured female (ZW) progenies destined to die. These findings suggest that (i) wSca, a male killer, carries a genetic factor that feminizes the male host, (ii) the sex-determining system of the host is degraded, and (iii) a mismatch between the genetic and phenotypic sexes underlies the sex-specific death
Programmed Chemotherapy for Patients with Metastatic Unresectable Gastric Cancer
BACKGROUND: Recent advances in the treatment of metastatic unresectable gastric cancers (MGC) include the development of new antitumor drugs and new regimens for their use. However, the selection of individually designed regimens by gastric cancer (GC) subtype remains problematic. Here, we investigated the clinical usefulness of programmed chemotherapy. METHODOLOGY/PRINCIPAL FINDINGS: MGC patients were classified into three groups by clinical condition. We implemented a chemotherapy program consisting of S-1 combination regimens. Median survival time (MST) of level 1 patients was 416 days (95% CI: 313-506 days), with an overall response rate of 47%. MSTs of level 2 and 3 patients were 208 (95% CI: 153-287 days) and 95 days (95% CI: 28-136 days), respectively. Grade 3-4 toxicities were neutropenia in 12% and anorexia in 6%. All treatment- related toxicities were resolved, and no treatment-related deaths occurred. CONCLUSIONS/SIGNIFICANCE: This program provided reasonable selection of case-matching regimens and may improve the survival of patients with MGC. Further, it may represent the first clinical tool to provide efficient chemotherapy course selection for MGC. Ongoing analysis of newly developed drugs and regimens will allow the efficacy of this chemotherapy program to be improved
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
Search for gravitational-lensing signatures in the full third observing run of the LIGO-Virgo network
Gravitational lensing by massive objects along the line of sight to the source causes distortions of gravitational wave-signals; such distortions may reveal information about fundamental physics, cosmology and astrophysics. In this work, we have extended the search for lensing signatures to all binary black hole events from the third observing run of the LIGO--Virgo network. We search for repeated signals from strong lensing by 1) performing targeted searches for subthreshold signals, 2) calculating the degree of overlap amongst the intrinsic parameters and sky location of pairs of signals, 3) comparing the similarities of the spectrograms amongst pairs of signals, and 4) performing dual-signal Bayesian analysis that takes into account selection effects and astrophysical knowledge. We also search for distortions to the gravitational waveform caused by 1) frequency-independent phase shifts in strongly lensed images, and 2) frequency-dependent modulation of the amplitude and phase due to point masses. None of these searches yields significant evidence for lensing. Finally, we use the non-detection of gravitational-wave lensing to constrain the lensing rate based on the latest merger-rate estimates and the fraction of dark matter composed of compact objects
Microscopic hole-transfer efficiency in organic thin-film transistors studied with charge-modulation spectroscopy
While the microscopic transfer properties of carriers are of primary importance for carrier transport of organic semiconductors, the mesoscopic features including the morphologies of grains and the structure of grain boundaries limit the overall carrier transport particularly in polycrystalline organic thin films. Thus the conventional evaluation methods of carrier mobility that rely on macroscopic properties such as I−V curves of devices are not capable to determine carrier transfer probability at the molecular level. Here, we present a method for evaluating the relative strengths of transfer integrals using charge-modulation spectroscopy on thin-film transistors of dinaphtho[2,3−b:2′,3′-f]thieno[3,2−b]thiophene (DNTT) and its alkylated derivatives (Cn-DNTT, n=8, 10, and 12). The band edges of absorption spectra of holes at around 1.9 eV show bathochromic shifts with increasing length of alkyl chains introduced at both ends of a DNTT chromophore. Applying a two-dimensional model with Holstein-type Hamiltonians to electronic transitions of holes, we have been able to simulate the features of the absorption band edges observed. The simulations indicate that the bathochromic shifts are due to an increase in the transfer integrals of holes with increasing length of alkyl chains. Thus this analysis confirmed that the subtle changes in the mutual orientations between adjacent DNTT chromophores induced by alkyl chains enhance the microscopic hole transfer rate. Although this fastener effect has been suggested by hole mobility measurements by I−V curves, the spectral analysis in this study gives clear evidence of this effect at the molecular level
The Pacific lineage (2E) of JC polyomavirus is prevalent in Sumba Island, Eastern Indonesia
Recent studies have identified a Pacific lineage (2E) of JC polyomavirus (also designated as JC virus or JCV) that occurs in both Island Southeast Asia and Oceania, but not in mainland Asia. It has been postulated that this lineage traveled with Austronesian-speaking people who are now spread throughout Island Southeast Asia and Oceania (excluding Australia and inland and southern New Guinea). However, to date, the 2E lineage has been identified in Southeast Asia only in populations of the Philippine islands. Here we report that a high incidence of the 2E lineage was detected in the people of Sumba Island, eastern Indonesia
Effect of quorum sensing inducers and inhibitors on male-killing Wolbachia, the endosymbiont of the adzuki bean borer, Ostrinia scapulalis (Lepidoptera: Crambidae)
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Autophagic chemicals effect for male-killing Wolbachia, Atg8 and TOR genes in Ostrinia scapulalis (Lepidoptera:Crambidae)
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