An integrated host-microbiome response to atrazine exposure mediates toxicity in Drosophila

The gut microbiome produces vitamins, nutrients, and neurotransmitters, and helps to modulate the host immune system-and also plays a major role in the metabolism of many exogenous compounds, including drugs and chemical toxicants. However, the extent to which specific microbial species or communities modulate hazard upon exposure to chemicals remains largely opaque. Focusing on the effects of collateral dietary exposure to the widely used herbicide atrazine, we applied integrated omics and phenotypic screening to assess the role of the gut microbiome in modulating host resilience in Drosophila melanogaster. Transcriptional and metabolic responses to these compounds are sex-specific and depend strongly on the presence of the commensal microbiome. Sequencing the genomes of all abundant microbes in the fly gut revealed an enzymatic pathway responsible for atrazine detoxification unique to Acetobacter tropicalis. We find that Acetobacter tropicalis alone, in gnotobiotic animals, is sufficient to rescue increased atrazine toxicity to wild-type, conventionally reared levels. This work points toward the derivation of biotic strategies to improve host resilience to environmental chemical exposures, and illustrates the power of integrative omics to identify pathways responsible for adverse health outcomes

Short rapid steps to provoke freezing of gait in Parkinson's disease

Item does not contain fulltextFreezing of gait (FOG) is both common and debilitating in patients with Parkinson's disease. Due to its episodic nature, it is a challenge to provoke FOG in clinical practice and in the research setting. Turning is most sensitive to provoke FOG, particularly when performed as rapidly as possible. Walking with short steps is an alternative approach to provoke FOG. Here, we assessed a modified version of this test, consisting of the instruction to make short steps as rapidly as possible. We evaluated what the diagnostic value of this new test is compared to rapid turning. 28 patients with Parkinson's disease participated, who all had objective FOG. Patients performed the following tasks two times: (1) normal walking, (2) walking as rapidly as possible, (3) walking with short steps, (4) walking with short steps as rapidly as possible and (5) making full rapid turns in both directions. FOG was provoked in 20 subjects (71 %). The most effective test to provoke FOG was rapid full turns (64 % of subjects). FOG occurred more often when patients walked with rapid short steps (50 %) compared to walking with short steps at normal speed (18 %). The combination of 'full rapid turns' and 'walking with short steps rapidly' yielded the highest sensitivity of provoking FOG (0.71, CI 0.51-0.86). The most sensitive way to provoke FOG is by asking patients to make full rapid turns, but if negative, walking with short steps as rapidly as possible can identify further subjects with FOG

Large variation in the use of defunctioning stomas after rectal cancer surgery. A lack of consensus

Surgical oncolog

Muscle fiber type grouping does not change in response to prolonged resistance exercise training in healthy older men

Background: Ageing of skeletal muscle is characterized in some by muscle fiber type grouping due to denervation-reinnervation cycles, but the severity of fiber type grouping varies widely across individuals of the same chro-nological age. It remains unknown whether fiber type grouping is associated with lower muscle mass and/or reduced physical function in elderly. Therefore, we assessed the relationship between fiber type grouping and indices of muscle mass and physical function in older adults. In addition, we assessed whether fiber type grouping is affected by prolonged resistance training in older adults.Methods: Twenty young (21 +/- 2 y) and twenty older (70 +/- 4 y) healthy men participated in the present study. Body composition (DXA-scan), quadriceps cross-sectional area (CT-scan) and muscle strength (1RM) were assessed at baseline (young and old) and following 12 weeks of resistance training (old only). Percutaneous skeletal muscle biopsies from the vastus lateralis were collected at baseline (young and old) and following exercise training (old only). Immunohistochemical analyses were performed to evaluate type I and type II muscle fiber distribution, size, myonuclear content and grouping.Results: At baseline, type II fibers were significantly (P < 0.05) smaller in older compared with young adults (5366 +/- 1288 vs 6705 +/- 1168 mu m2). Whereas no differences were observed in type I, type II fiber grouping was significantly (P < 0.05) lower in older (18 +/- 18 %) compared with young (32 +/- 25 %) men. No significant correlations were observed between fiber type grouping and muscle mass or physical function. Prolonged resistance training in old men resulted in a significant increase (P < 0.05) in type II fiber size (from 5366 +/- 1288 to 6165 +/- 1484 mu m2) with no significant changes in the proportion of type I muscle fibers found grouped.Conclusion: Muscle fiber type grouping is not associated with lower body strength or muscle mass in healthy, older men. In addition, twelve weeks of resistance exercise training results in type II muscle fiber specific hy-pertrophy but does not affect fiber type grouping

Optimal Treatment Strategy in Rectal Cancer Surgery: Should We Be Cowboys or Chickens?

Surgical oncolog

Sleep need in high school athletes

BACKGROUND: Freezing of gait (FOG) is a common and debilitating phenomenon in Parkinson's disease (PD). Wearable accelerometers might help to assess FOG in the research setting. Here, we evaluate whether accelerometry can detect FOG while executing rapid full turns and while walking with rapid short steps (the two most common provoking circumstances for FOG). METHODS: We included 23 PD patients, who all had objective FOG. Participants performed several walking tasks, including walking rapidly with short steps and rapid full turns in both directions with a triaxial linear waist-mounted accelerometer. Two independent experts identified FOG episodes using off-line video-analysis (gold standard). A validated algorithm [ratio between pathological freezing (3-8 Hz)-and normal locomotor frequencies (0.5-3 Hz)] was applied on the accelerometer data to detect FOG episodes. RESULTS: Clinically, FOG was most often observed during full rapid turns (81% of all episodes), followed by walking with short rapid steps (12% of all episodes). During full rapid turns, accelerometry yielded a sensitivity of 78% and specificity of 59%. A sensitivity of 64% and specificity of 69% was observed during walking rapidly with small steps. Combining all tasks rendered a sensitivity of 75% and specificity of 76%. CONCLUSION: Our results suggest that FOG can be detected from a single lumbar accelerometer during several walking tasks, including full rapid turns and walking with short steps rapidly, with reasonable sensitivity and specificity. This approach holds promise for possible implementation as complementary objective outcome in a research setting, but more work remains needed to improve the sensitivity and specificity