Fecal microbiota transplantation ameliorates high-fat diet-induced memory impairment in mice.

Gut dysbiosis is linked to metabolic and neurodegenerative diseases and comprises a plausible link between high-fat diet (HFD) and brain dysfunction. Here we show that gut microbiota modulation by either antibiotic treatment for 5 weeks or a brief 3-day fecal microbiota transplantation (FMT) regimen from low-fat (control) diet-fed mice decreased weight gain, adipose tissue hypertrophy, and glucose intolerance induced by HFD in C57BL/6 male mice. Notably, gut microbiota modulation by FMT completely reversed impaired recognition memory induced by HFD, whereas modulation by antibiotics had less pronounced effect. Improvement in recognition memory by FMT was accompanied by decreased HFD-induced astrogliosis in the hippocampal cornu ammonis region. Gut microbiome composition analysis indicated that HFD diminished microbiota diversity compared to control diet, whereas FMT partially restored the phyla diversity. Our findings reinforce the role of the gut microbiota on HFD-induced cognitive impairment and suggest that modulating the gut microbiota may be an effective strategy to prevent metabolic and cognitive dysfunction associated with unfavorable dietary patterns.

Food safety knowledge, attitudes and practices of food handlers: A cross-sectional study in school kitchens in Espírito Santo, Brazil.

BACKGROUND: The adoption and evaluation of good practices in food handling in food service are essential to minimizing foodborne diseases. The present study aimed to evaluate food safety knowledge, attitudes, and practices of food handlers in schools in Vitória, Brazil. METHODS: A cross-sectional study was carried out in the school food services of the municipal network of Vitória-ES. The sample of food handlers was obtained by convenience and comprised food handlers involved with preparation and other kitchen-related activities. The instrument consisted of a structured questionnaire with 36 six questions that included sociodemographic characteristics, knowledge, attitudes, and practices (KAP) related to good practices and food safety. The questionnaire was answered by 172 food handlers. Pearson correlation test, T-test, Tukey's test and multiple linear regression analysis were conducted. Data entry and analysis were done using SPSS v.20 software. RESULTS: Most of the participants were female (96.5%, n = 166), were 40 to 49 years old (44.8%, n = 78), attended high school (57.9%, n = 99), had up to 5 years of experience in the role (39.5%, n = 68). Some of them had participated at least 4 times in training (74.4%, n = 128) of which the most recent session had occurred within 3 months (52.0%, n = 44). The lowest score was obtained for knowledge (7.1 ± 1.22). All the models presented significant results for the F-test. This result show good model fit and results ranging from 1.5 to 2.5 on the Durbin Watson test of residual autocorrelation. The linear regression analysis allowed us to identify that the knowledge score increased with experience, but it was significant only for those who had spent up to 10 years in the role. The knowledge score was associated with experience and training time. Attitudes were significantly related to the schooling and training time. The increase in the classification of practices is shown only through a classification of attitudes. CONCLUSIONS: Although the food handlers' knowledge level in general was considered as sufficient, it was inferior to their scores for attitudes and practices regarding certain food safety concepts. Food safety training is ongoing in these units and covers the main aspects that favour the transformation of knowledge into appropriate attitudes and practices.

Rovers minimize human disturbance in research on wild animals.

Investigating wild animals while minimizing human disturbance remains an important methodological challenge. When approached by a remote-operated vehicle (rover) which can be equipped to make radio-frequency identifications, wild penguins had significantly lower and shorter stress responses (determined by heart rate and behavior) than when approached by humans. Upon immobilization, the rover-unlike humans-did not disorganize colony structure, and stress rapidly ceased. Thus, rovers can reduce human disturbance of wild animals and the resulting scientific bias.

Early-life metabolic dysfunction impairs cognition and mitochondrial function in mice.

The impact of overnutrition early in life is not restricted to the onset of cardiovascular and metabolic diseases, but also affects critical brain functions related to cognition. This study aimed to evaluate the relationship between peripheral metabolic and bioenergetic changes induced by a two-hit protocol and their impact on cognitive function in juvenile mice. Three-week-old male C57BL/6 mice received a high-fat diet (HFD) or control diet for 7 weeks, associated with two low doses of streptozotocin (STZ) or vehicle. Despite the absence of obesity, HFD+STZ impaired glucose metabolism and induced a trend towards cholesterol increase. The two-hit protocol impaired recognition and spatial memories in juvenile mice, without inducing a depressive-like behavior. HFD+STZ mice presented increased immunoreactivity for GFAP and a trend towards a decrease in NeuN in the hippocampus. The treatment caused a bioenergetic impairment in the hippocampus, characterized by a decrease in both O2 consumption related to ATP production and in the maximum respiratory capacity. The thermogenic capacity of brown adipose tissue was impaired by the two-hit protocol, here verified through the absence of a decrease in O2 consumption after uncoupled protein-1 inhibition and an increase in the reserve respiratory capacity. Impaired mitochondrial function was also observed in the liver of HFD+STZ juvenile mice, but not in their heart. These results indicate that exposure to HFD+STZ early in life has a detrimental impact on the bioenergetic and mitochondrial function of tissues with metabolic and thermogenic activities, which is likely related to hippocampal metabolic changes and cognitive impairment.

The association between excess body weight at diagnosis and pediatric leukemia prognosis: A systematic review and meta-analysis.

Obesity affects the prognosis of several types of cancer. However, whether excess body weight is independently associated with adverse outcomes following initial pediatric acute leukemia (AL) treatment is still unclear. We conducted a systematic review and meta-analysis to investigate the impact of overweight/obesity at diagnosis on pediatric AL prognosis following initial treatment by performing an extensive database search up to January 22, 2021. Twenty-three studies were included, providing data for 15689 children with acute lymphoblastic leukemia (ALL) and 2506 children with acute myeloid leukemia (AML). Data from 12 studies were pooled in the meta-analysis. Children with overweight/obesity at diagnosis of ALL had poorer event free-survival (random-effects hazard ratio of 1.44, 95%CI 1.16-1.79, p = 0.0008), but no difference in overall survival (random-effects hazard ratio 1.33, 95%CI 0.77-2.29, p = 0.31) when compared with healthy-weight children. Children with overweight/obesity at diagnosis of AML had no difference in event-free survival (random-effects hazard ratio of 0.88, 95%CI 0.48-1.59, p = 0.66) or overall survival (random-effects hazard ratio 1.40, 95%CI 0.78-2.49, p = 0.26), when compared with healthy-weight children. This systematic review and meta-analysis indicates that overweight/obesity negatively affects the prognosis of children with ALL. Future studies should address the best approach to consider nutritional status in their management.