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Mitochondrial DNA (mtDNA) mutations, including the m.3243A>G mutation that causes mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS), are associated with secondary coenzyme Q10 (CoQ10) deficiency. We previously demonstrated that PPARGC1A knockdown repressed the expression of PDSS2 and several COQ genes. In the present study, we compared the mitochondrial function, CoQ10 status, and levels of PDSS and COQ proteins and genes between mutant cybrids harboring the m.3243A>G mutation and wild-type cybrids. Decreased mitochondrial energy production, defective respiratory function, and reduced CoQ10 levels were observed in the mutant cybrids. The ubiquinol-10:ubiquinone-10 ratio was lower in the mutant cybrids, indicating blockage of the electron transfer upstream of CoQ, as evident from the reduced ratio upon rotenone treatment and increased ratio upon antimycin A treatment in 143B cells. The mutant cybrids exhibited downregulation of PDSS2 and several COQ genes and upregulation of COQ8A. In these cybrids, the levels of PDSS2, COQ3-a isoform, COQ4, and COQ9 were reduced, whereas those of COQ3-b and COQ8A were elevated. The mutant cybrids had repressed PPARGC1A expression, elevated ATP5A levels, and reduced levels of mtDNA-encoded proteins, nuclear DNA-encoded subunits of respiratory enzyme complexes, MNRR1, cytochrome c, and DHODH, but no change in TFAM, TOM20, and VDAC1 levels. Alterations in the CoQ10 level in MELAS may be associated with mitochondrial energy deficiency and abnormal gene regulation. The finding of a reduction in the ubiquinol-10:ubiquinone-10 ratio in the MELAS mutant cybrids differs from our previous discovery that cybrids harboring the m.8344A>G mutation exhibit a high ubiquinol-10:ubiquinone-10 ratio.

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In this study, we investigated contamination rates and possible contamination routes of Salmonella in two typical tilapia sashimi processing plants in Taiwan. We found that the overall isolation rate was 5.0% ( n = 61), from a total of 1,218 samples collected in a year from different processing sections (freezing, scaling and bleeding, visceral removal, washing and disinfection, and packaging) and from different operating times (before processing and 3 and 6 h after processing began). In plant A, which is a relatively well-operated plant compared with plant B, Salmonella was only found in the freezing, scaling and bleeding, and visceral removal sections, with isolation rates ranging from 0 to 9.3%. No Salmonella was identified in the final ready-to-eat products at plant A. In plant B, Salmonella was found in all sections and in the final products, with isolation rates ranging from 4.6 to 36.1%. Regarding the processing times, the contamination rates increased significantly ( P < 0.05) 3 h after processing began in plant B. Among the isolates, 10 serotypes were detected, some of which are commonly observed in human salmonellosis cases in Taiwan, indicating a risk of zoonoses. However, only four isolates showed antimicrobial resistance in the current study. With molecular subtyping, we observed accumulated and persistent Salmonellae contamination patterns in plant B. These results suggest that inadequate sanitation impairs the foodborne pathogen control program in tilapia sashimi plants.

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BACKGROUND: Hepatocellular carcinoma (HCC) has multiple prognostic factors, and there is an increase in knowledge about the body composition and physical status of patients with HCC. The present meta-analysis aimed to explore whether loss of skeletal muscle mass is associated with mortality and tumor recurrence in patients with HCC. METHOD: A systematic search was conducted for published literature using PubMed, Embase, and Scopus. We included cohort or case-control studies investigating patients with HCC. The primary and secondary outcomes were the associations of loss of skeletal muscle mass with overall survival and tumor recurrence, respectively, expressed by a summary hazard ratio (HR) and 95% confidence interval (CI). RESULT: A total of 13 studies comprising 3,111 patients were included. The summary HRs calculated by either univariate or multivariate analysis both suggested a significant association between sarcopenia and all-cause mortality (crude HR = 2.04, 95% CI: 1.74-2.38; adjusted HR = 1.95, 95% CI: 1.60-2.37). Similarly, loss of skeletal muscle mass was associated with tumor recurrence (crude HR = 1.85, 95% CI: 1.44-2.37; adjusted HR = 1.76, 95% CI: 1.27-2.45). The stratified analysis showed that treatment types and inclusion of body mass index or body weight in the Cox regression model did not modify both clinical outcomes. With an increase in cut-off values of muscle mass on computed tomography images (especially for male patients), there was an insignificant trend of stronger associations between loss of skeletal muscle mass and all-cause mortality. CONCLUSION: Loss of skeletal muscle mass is associated with increased all-cause mortality and tumor recurrence in patients with HCC. Further prospective studies incorporating measurements of muscle strength and physical function are warranted to see whether inclusion of both parameters better predicts the outcome than use of muscle mass only.