一抗体免疫法によるPorphyromonas. gingivalis SODの定量(プレリミナリーレポート)

Superoxide dismutase (SOD) as a free radical scavenger in Porphyromonas gingivalis is well documented. The aim of this work was to develop an enzyme-linked immunosorbent assay using recombinant P. gingivalis SOD as an antigen. The sandwich complex was detected using a secondary antibody conjugated to β-D-galactosidase. Under optimum conditions, the sensitivity and the limit of detection were determined from 25pg to 500pg. In future, the application will be extended to the expression of SOD from P. gingivalis under various growing conditions

Streptococcus anginosus のプロリルトリペプチジルペプチダーゼの産生と酵素性状

Streptococcus anginosus is considered to be implicated in the etiology of oral infectious diseases as well as abscess formation in various body sites. We investigated the production and the enzymatic properties of PTP of S. anginosus NCTC 10713. This enzyme was found only in cell extract and active on tripeptide substrates containing proline residue at P1 position, particularly H−Ala−Ala−Pro−p−nitroanilide. The enzyme was produced by all 8 species of tested streptococci, indicating occurrence of this enzyme is rather ubiquitous within streptococci. This PTP was purified to homogeneity from the cell extract by the procedures including ammonium sulfate precipitation, chromatography, gel filtration and electrophoresis. The enzyme was inhibited by serine enzyme inhibitors and chelating reagents, indicating this PTP is a serine metalloenzyme with a molecular mass of 66 kDa. The enzyme was active against H−Ala−Ala−Pro−p−nitroanilide and H−Ala−Phe−Pro−p−nitroanilide in neutral pH solutions. The activity was completely lost by heating at 50°C for 10min

An Esophageal Ulcer Associated with a Thoracoabdominal Aortic Aneurysm

An aortoesophageal fistula, an abnormal anatomical communication between the aorta and the esophagus, is a rare cause of upper gastrointestinal bleeding. The mortality rate of patients with this condition is very high. A 77-year-old man, who had undergone endovascular aortic repair for a ruptured abdominal aortic aneurysm, developed melena. An upper gastrointestinal endoscopy was performed. This detected an esophageal ulcer, which had the potential to develop into an aortoesophageal fistula. Therefore, thoracic endovascular aortic repair was performed on the following day. Thereafter, the course was uneventful. We encountered a rare case of an esophageal ulcer associated with a thoracoabdominal aortic aneurysm before it developed into an aortoesophageal fistula

Aortic Dissection in a Patient with Human Immunodeficiency Virus Infection That was Diagnosed at Autopsy : A Case Report.

A 43-year-old homosexual man was referred to our hospital for chest pain and loss of consciousness. He was hypertensive, and had an uncontrolled viral load. Serum creatinine revealed acute renal failure, and he died 3 days later. On autopsy, aortic dissection (TypeB) was found. No obvious inflammatory change, granulation, bacterial or fungal infection, or medionecrosis were seen at the dissection site. To our knowledge, this was the first case with HIV in whom aortic dissection was diagnosed at autopsy. Aortic dissection is a potential differential diagnosis even in young patients presenting with hypertension and chest pain

A Case of Gastroparesis after Cryoballoon Ablation followed by Medication-Induced Recovery within 6 Months

Atrial fibrillation (AF) is the most common cardiac arrhythmia, and cryoballoon ablation was developed as a new treatment modality for symptomatic AF. Gastroparesis is rarely reported as a transient complication of ablation, and its frequency and risk are not clear. We experienced a rare case of gastroparesis after cryoballoon ablation followed by medication-induced recovery within 6 months

Porphyromonas gingivalis SOD における活性中心近傍に局在するアミノ酸残基の金属特異的活性における関与：Leu ₇2 Trp およびLeu ₇6 Phe の2残基変異による検討

The role of superoxide dismutase (SOD) as a radical scavenger in Porphyromonas gingivalis is well documented. P. gingivalis SOD (Pg SOD), which is characterized by a metal–tolerant activity, can use either iron or manganese as a cofactor. Leu ₇2 and Leu ₇6, located near the active–site metal, are characteristic amino acid sequences of Pg SOD proteins, although they are substituted to Trp in the ₇2 position and Phe in the ₇6 position in most iron–containing SOD (Fe–SOD) proteins. In the present study, we constructed a mutant of the enzyme with changes from Leu ₇2 to Trp and Leu ₇6 to Phe. This mutant SOD was examined with respect to its metal–dependent activity and structural characterization. We herein conclude the integrity of Leu ₇2 and Leu ₇6 is a necessary requisite for the metal–tolerant activity of Pg SOD

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