[Epidemiological and etiological characteristics of Vibrio parahaemolyticus strains causing foodborne disease outbreaks in Guangdong Province from 2017 to 2020].

Objective: To study the epidemiological and pathogenic characteristics of Vibrio parahaemolyticus isolated from outbreaks cases in Guangdong Province, 2017-2020. Methods: Epidemiological characteristics of 87 outbreak events caused by Vibrio parahaemolyticus were analyzed. Strains were serotyped, and then analyzed by pulsed-field gel electrophoresis (PFGE). Results: The food-borne disease outbreak caused by Vibrio parahaemolyticus was found in 16 cities. 44.8% (39/87) and 37.9% (33/87) of the outbreaks occurred in hotels, restaurants and school canteens, respectively. Improper food processing and storage (40.2%, 35/87) and cross contamination caused by indiscriminate raw and cooked food (25.3%, 22/87) were the main causes of food-borne disease outbreaks of Vibrio parahaemolyticus. The main serotypes of patient derived strains were O3:K6 (87.5%) and O4:KUT (22.5%). The similarity value between O3:K6 type isolates was 65.5%-100.0%, and the PFGE pattern similarity value of O4:KUT type isolates was 66.5%-100.0%. Conclusion: Outbreaks caused by Vibrio parahaemolyticus are widely distributed in Guangdong province. It is necessary to strengthen the publicity and education on the correct handling of food in hotels, restaurants, schools, and unit canteens. O3:K6 and O4:KUT serotypes are the main serotypes of the outbreak. There is genetic diversity among the epidemic strains.

Group housing with young mice relieves Alzheimer's disease behaviors in aging mice.

OBJECTIVE: Due to the increase in human life expectancy, a higher number of individuals are experiencing age-related cognitive impairments. Therefore, it is important to investigate the methods to tackle the effects of aging. MATERIALS AND METHODS: The mice were divided into the following groups: the aging mice (male, 20 months) and young mice (male, 2 months) were pairing-housed together in the same cage and lasted for at least one month (Aging-Young). The following tests were performed for the mice in different groups: Open field test, Morris water maze (MWM) test, Contextual fear conditioning test, Novel Object Recognition (NOR) test, Pain threshold test, Olfactory habituation/dishabituation test, T-maze test, Electrophysiological recordings. RESULTS: In this study, we housed aging and young mice together, and found that the paired housing for one-month improved the learning and memory of the aging mice. These mice exhibited better performance on the Morris water maze (MWM) test, a longer freezing duration in the contextual fear conditioning test, a higher alternation rate in the T-maze test, and an increased preference for novel objects in the novel object recognition (NOR) test. The paired housing with young mice also improved the impaired long-term potentiation (LTP) in aging mice. CONCLUSIONS: Our results suggest that the paired housing with young mice has beneficial effects on learning and memory of aging mice. The manipulation of the systemic environment may, therefore, provide a new strategy for aging rejuvenation.

Artemisinin for treatment of uncomplicated falciparum malaria: is there a place for monotherapy?

The efficacy of artemisinin monotherapy was studied in 227 patients with uncomplicated falciparum malaria. They all received artemisinin at t = 0 hr, t = 8 hr, and thereafter once daily; treatment was extended at random until they had taken either 5 days of artemisinin followed by 2 days of placebo (A5), or 7 days (A7) of artemisinin. The adult artemisinin dose was 500 mg; children aged < 15 years received 10 mg/kg per dose. The median (range) parasite clearance time was 39 (8-112) hr for A5 and 43 (38-104) hr for A7 (P = 0.085). The recrudescence rates were similar between the groups. The lowest parasite count achieved during treatment (Pterm) was associated with the occurrence of recrudescence (P = 0.046, Cox regression model); it was lower for patients with a radical cure or late recrudescence than for early recrudescence (P = 0.034, t-test). Artemisinin monotherapy may offer rapid recovery and fast parasite clearance, but recrudescence is frequent. Extending the duration of monotherapy from 5 days to 7 days does not reduce recrudescence.