14 research outputs found
Early-phase migration dynamics of Echinococcus multilocularis in two mouse strains showing different infection susceptibilities
The early-phase migration dynamics of Echinococcus multilocularis in the intermediate hosts remain largely unknown. We compared the parasite burden in the intestine, liver and faeces of DBA/2 and C57BL/6 mouse strains using parasite-specific quantitative PCR. Our results indicated that the parasites invaded mainly from the middle segments of the small intestine and completed migration to the liver within 24 h p.i. C57BL/6 mice had lower parasite DNA burdens in the intestine and liver but higher in the faeces than DBA/2 mice, suggesting that parasite invasion of the intestine may be a critical stage regulating susceptibility to E. multilocularis infection in mice. (c) 2021 Australian Society for Parasitology. Published by Elsevier Ltd. All rights reserved
Characterization of microRNAs expressed in the cystic legion of the liver of Mus musculus perorally infected with Echinococcus multilocularis Nemuro strain
Alveolar echinococcosis (AE) is a zoonosis caused by the metacestode of Echinococcus multilocularis. The published genome of E. multilocularis showed that approximately 86% of its genome is non-coding. Micro RNAs (miRNAs) are small non-coding regulatory RNAs, and recent studies on parasitic helminths expect miRNAs as a promising target for drug development and diagnostic markers. Prior to this study, only a few studies reported the E. multilocularis miRNA profiles in the intermediate host. The primary objective of this study was to characterize miRNA profiles via small RNA-seq in E. multilocularis Nemuro strain, a laboratory strain of Asian genotype, using mice perorally infected with the parasite eggs. The data were then compared with two previously published small RNA-seq data. We identified 44 mature miRNAs as E. multilocularis origin out of the 68 mature miRNA sequences registered in the miRNA database miRbase. The highest quantities of miRNAs detected were miR-10-5p, followed by bantam-3p, let-7-5p, miR-61-3p, and miR-71-5p. The top two most abundant miRNAs (miR-10-5p and bantam-3p) accounted for approximately 80.9% of the total parasite miRNAs. The highly expressed miRNA repertoire is mostly comparable to that obtained from the previous experiment using secondary echinococcosis created by an intraperitoneal administration of metacestodes. A detailed characterization and functional annotations of these shared miRNAs will lead to a better understanding of parasitic dynamics, which could provide a basis for the development of novel diagnostic and treatment methods for AE. Superscript/Subscript Available ABSTRACT Alveolar echinococcosis (AE) is a zoonosis caused by the metacestode of Echinococcus multilocularis. The published genome of E. multilocularis showed that approximately 86% of its genome is non-coding. Micro RNAs (miRNAs) are small non-coding regulatory RNAs, and recent studies on parasitic helminths expect miRNAs as a promising target for drug development and diagnostic markers. Prior to this study, only a few studies reported the E. multilocularis miRNA profiles in the intermediate host. The primary objective of this study was to characterize miRNA profiles via small RNA-seq in E. multilocularis Nemuro strain, a laboratory strain of Asian genotype, using mice perorally infected with the parasite eggs. The data were then compared with two previously published small RNA-seq data. We identified 44 mature miRNAs as E. multilocularis origin out of the 68 mature miRNA sequences registered in the miRNA database miRbase. The highest quantities of miRNAs detected were miR-10-5p, followed by bantam-3p, let-7-5p, miR-61-3p, and miR-71-5p. The top two most abundant miRNAs (miR-10-5p and bantam-3p) accounted for approximately 80.9% of the total parasite miRNAs. The highly expressed miRNA repertoire is mostly comparable to that obtained from the previous experiment using secondary echinococcosis created by an intraperitoneal administration of metacestodes. A detailed characterization and functional annotations of these shared miRNAs will lead to a better understanding of parasitic dynamics, which could provide a basis for the development of novel diagnostic and treatment methods for AE
Operation Range of Intermittent Velocity Control for Improving Top-Dead-Center Accuracy in Dual-Sided Free-Piston Engine Linear Generator
A free-piston engine linear generator (FPEG) is constructed by combining a reciprocating internal combustion engine and a linear generator. FPEG is required to improve both the accuracy of the top-dead-center (TDC) positioning considering frequent combustion fluctuations and the reduction of power consumption. This paper confirms the influence of intermittent velocity control on power running suppression and TDC position deviation in a dual-cylinder FPEG. Intermittent velocity control is a simple method, which consists of repeatedly turning the speed control on and off. The experimental results of the glow engine indicate that this control suppresses power consumption and enables continuous combustion. The setting range for intermittent speed control, which continues operation only through regenerative operation, must be determined by considering the gain value. In addition, this paper explains the effects of the control range of intermittent velocity control on power generation efficiency, piston motion frequency, and TDC position deviation in the dual-cylinder FPEG. Increasing the range ratio of intermittent speed control improves power generation efficiency, but it also increases the standard deviation of TDC position
Usefulness of plasminogen activator inhibitor-1 as a predictive marker of mortality in sepsis
Abstract Background Sepsis is one of the most significant causes of mortality in intensive care units. It indicates crosstalk between inflammation and coagulation. In this study, we aimed to identify prognostic markers among sepsis biomarkers and coagulation/fibrinolysis markers. Methods Patients with sepsis according to the Sepsis-3 criteria were enrolled from January 2013 to September 2015. Univariate and multivariate logistic regression analyses were performed to identify an independent predictive marker of 28-day mortality among sepsis biomarkers and coagulation/fibrinolysis markers on ICU admission. Receiver operating characteristic analysis was performed; the optimal cutoff value of 28-day mortality was calculated using the predictive marker. Patients were classified into two groups according to the cutoff level of the predictive marker. Patient characteristics were compared between the groups. Results A total of 186 patients were enrolled in this study; the 28-day mortality was 19.4% (36/186). PAI-1 was identified as the only independent predictive marker of 28-day mortality by univariate and multivariate logistic regression. The area under the curve was 0.72; the optimal cutoff level was 83 ng/ml (sensitivity, 75%; specificity, 61%). Patients were classified into a higher group (PAI-1 level ≥83 ng/ml; n = 85) and a lower group (PAI-1 level <83 ng/ml; n = 101). All disseminated intravascular coagulation (DIC) scores and Sequential Organ Failure Assessment score were significantly higher in the higher group than in the lower group. Conclusions PAI-1 can predict prognosis in sepsis patients. PAI-1 reflects DIC with suppressed fibrinolysis and organ failure, with microthrombi leading to microcirculatory dysfunction
Surveillance of Extended-Spectrum β-Lactamase-producing Carriage in a Japanese Intensive Care Unit: a Retrospective Analysis
Background The effectiveness of surveillance to identify extended-spectrum beta-lactamase-producing Enterobacteriaceae (ESBL-E) carriers is controversial during a non-outbreak situation. We performed additional stool cultures for ESBL-E among intensive care unit (ICU) patients already under active surveillance by means of sputum and urine cultures. We aimed to assess the efficacy of stool cultures for screening for ESBL-E in a non-outbreak situation. Methods We conducted a retrospective cohort study in an ICU. Sputum and urine samples were cultured for ESBL-E surveillance purposes from January to September 2013 (phase 1). Stool cultures were routinely performed in addition from January to September 2014 (phase 2). Antimicrobial use density values and clinical outcomes were investigated and compared between phase 1 and 2. Results We identified 512 and 478 patients in phase 1 and phase 2, respectively. ESBL-E were found in the feces of 65 (13.6%) patients in phase 2. The antimicrobial use density values (expressed as defined daily doses per 1,000 bed-days) were not significantly different between the two phases for fluoroquinolones (7 vs. 10, p = 0.376), third-generation cephalosporins (24.2 vs. 29.5, p = 0.724), tazobactam/ piperacillin (44.6 vs. 57.3, p = 0.489), and carbapenems (73 vs. 55.5, p = 0.222). Moreover, there were no significant differences in ICU mortality and length of stay (11.5% vs. 9.8%, p = 0.412, and 9 vs. 10 days, p = 0.28, respectively). Conclusions Stool culture seemed ineffective in improving the antimicrobial use density of broad-spectrum antimicrobials, clinical outcomes, and ICU length of stay, and is not recommended for surveillance of ESBL-E in a non-outbreak situation
Giant Polypoid Tumor Expressing on the Pyloric Ring
A 66-year-old Japanese man was referred to our hospital because of suspected duodenal cancer. Upper gastric endoscopy revealed a giant polypoid-type tumor that extended from the duodenum bulb to the pyloric ring. A computed tomography scan revealed a slightly enhanced lobular tumor protruding into the duodenum bulb. Positron emission tomography showed an accumulation of 18F-fluorodeoxyglucose in the area extending from the antrum of the stomach to the duodenum bulb. Since an endoscopic ultrasound test suggested that the tumor might invade the muscular tunic, indications of endoscopic mucosal resection were not favored, and the tumor was curatively removed via distal gastrectomy. The histopathologic diagnosis was papillary adenocarcinoma, and the invasion depth was the mucosal layer without vascular invasion, which was different from the preoperative diagnosis. Our case suggests the difficulties in precise diagnosis of the invasion depth of the giant polypoid cancer