[Sentinel surveillance for viral hepatitis C in China, 2016-2017].

Objective: To understand the prevalence of hepatitis C virus (HCV) infection in 5 populations in China during 2016-2017 and provide evidence for the estimation of prevalence trend of hepatitis C and evaluation on the prevention and control effect. Methods: A total of 87 national sentinel surveillance sites for hepatitis C were set up in 31 provinces (autonomous regions and municipalities) of China to obtain the information about HCV infection prevalence in 5 populations, including volunteer blood donors, people receiving physical examination, patients receiving invasive diagnosis and treatment, patients receiving hemodialysis, and clients visiting family planning outpatient clinics. From April to June, 2016 and 2017, cross-sectional surveys were repeatedly conducted in the 5 populations and blood samples were collected from them for HCV antibody detection. Results: In 2016, 86 sentinel sites completed the surveillance (one sentinel site was not investigated), and 115 841 persons were surveyed. The overall HCV positive rate was 0.38% (442/115 841, 95%CI: 0.23%-0.53%). In 2017, all the 87 sentinel sites completed the surveillance, and 120 486 persons were surveyed. The overall HCV positive rate was 0.37% (449/120 486, 95%CI: 0.23%-0.52%). In 2016 and 2017, the anti-HCV positive rates were 4.46% (223/5 005, 95%CI: 2.18%-6.73%) and 4.39% (216/4 919, 95%CI: 2.29%-6.50%) respectively in hemodialysis patients, 0.85% (44/5 200, 95%CI: 0.27%-1.42%) and 0.70% (36/5 150, 95%CI: 0.15%-1.24%) respectively in patients receiving invasive diagnosis and treatment and remained to be ≤0.25% in volunteer blood donors, people receiving physical examination and clients visiting family planning outpatient clinics. Results for the comparison of the anti-HCV positive rates in the 5 populations indicated that the differences were significant (F=23.091, P<0.001 in 2016 and F=20.181, P<0.001 in 2017). Conclusions: Data from the sentinel surveillance of HCV infection on prevalence in China showed that the anti-HCV positive rates varied in the 5 populations during 2016-2017. The anti-HCV positive rate appeared the highest in the hemodialysis patients, followed by that in the patients receiving invasive diagnosis and treatment, and the prevalence of HCV infection in other 3 populations were at low levels.

Effects of hyperbaric oxygen on S-180 sarcoma in mice.

The contents of oxygen free radicals (OFRs) and malondialdehyde (MDA) in S-180 sarcoma tissues were measured in four groups of mice: an untreated normoxic group, a normoxic hyperbaric group, a hyperbaric oxygen group, and an HBO group treated with superoxide dismutase (SOD). Measurements were done by electron resonance and spectrophotometry, and observations were made on the volume, weight, necrosis incidence rate of sarcoma tissues, and mortality in all groups. The OFR and MDA content in sarcoma tissues in the HBO group was significantly higher than those of the control groups (P < 0.001); necrosis incidence of sarcoma tissues and the survival rate of mice were higher; the time required for necrosis was shorter, and the volume and weight of sarcoma tissues were smaller and lighter than those of the control groups (P < 0.01). The results suggest that SOD cannot completely eliminate OFRs produced by hyperbaric exposure, although the role of HBO in producing more OFRs can be counterbalanced by SOD to a certain degree. Apparently HBO can check the growth rate of sarcoma and accelerate the necrosis of S-180 sarcoma cells.

[Changes of Leu-enkephalin in striatum and hypothalamus of rats during hyperbaric oxygen exposure].

The purpose of this study is to investigate the changes of Leu-Enkephalin (L-Enk) content in striatum and hypothalamus of rats during hyperbaric (HBO) oxygen exposure. Thirty-two male rats in the experiment were randomly divided into four groups: normobaric air group, normoxic hyperbaric nitrox group, nonconvulsion HBO group and convulsion HBO group. L-Enk content in striatum and hypothalamus was determined by radioimmunoassay. The results show that L-Enk content in the striatum and hypothalamus of rats exposed to hyperbaric oxygen environment were markedly higher than that of rats exposed to normobaric air and normoxic hyperbaric nitrox. The experimental results suggest that the elevation of L-Enk content in striatum and hypothalamus shows a positive relationship with the HBO exposure duration of animals and that there was no marked relationship with normoxic hyperbaric nitrox environment and compression-decompression method.