Anthropogenic fire patterns affect niche breadth and niche overlap in sympatric songbird species.

The severity of wildfires increases globally, and return intervals decrease. Fires can benefit biodiversity, as post-burn early successional stages provide diverse habitats and niches for many species. How fire disturbance affects niche use and niche overlap of species is poorly understood so far. We studied the effect of anthropogenic fire on breeding habitat use, niche breadth and niche overlap of five sympatric bunting species breeding in wetlands of the Amur River floodplain (Russian Far East). Fire frequency, measured as the time an area burnt in the period 2000 to 2017, was mapped from Landsat imagery and related to the presence or absence of the species. Niche breadth and niche overlap were calculated separately for occurrences in burned (within the study year) and unburned patches. Fire frequency characterized differences in niche use among the species, but the probability of presence was not affected by recent fire in four of five species. Niche breadth was significantly lower in recently burned patches, but we found no increase in niche overlap between species after fire. Instead, the studied species seemed to occupy similar patches before and after fire, possibly because of a high site fidelity. Our results clearly show that fire frequency is a major determinant for the niche separation in the five studied species, while recent fire does not affect niche overlap.

[Viral arthritis]. / Les arthrites virales.

Viral arthritis are very frequent and usually self limited to a few weeks. The most common pathophysiological mechanism is immune complexes deposit and not a direct invasion of the synovium. The typical clinical presentation is a peripheral and symmetrical polyarthritis, undistinguishable from other inflammatory arthritis. If virtually any virus can cause arthritis, it seems reasonable to limit investigations to the demonstration of the few viruses for which the therapy would be modified, namely hepatitis viruses and HIV. Serology remains the most common method to establish the diagnosis. From a therapeutic point of view, there is no specific treatment. Simple symptomatic measurements are sufficient.

A randomized controlled trial of dehydroepiandrosterone in postmenopausal women with fibromyalgia.

OBJECTIVE: Patients with fibromyalgia (FM) consistently have adrenal hyporesponsiveness and low dehydroepiandrosterone (DHEA) levels. DHEA is promoted for and used by patients with FM. We tested the efficacy and safety of DHEA supplementation in ameliorating the symptoms of FM. METHODS: In a double-blind crossover study, postmenopausal women with FM were randomized to DHEA supplementation (50 mg/day) or placebo for 3 months, with a one-month washout period in between. Patients were assessed monthly for well-being and pain and by medical evaluations at the beginning and the end of each treatment period. The primary outcome was well being; secondary outcomes were pain, fatigue, cognition, sexuality, functional impairment, depression, and anxiety. RESULTS: A total of 52 patients were randomized, 47 patients completed the DHEA treatment period, and 45 the placebo treatment period. After 3 months of treatment with 50 mg of DHEA, median DHEA sulfate blood levels had tripled, but there was no improvement in well-being, pain, fatigue, cognitive dysfunction, functional impairment, depression, or anxiety, nor in objective measurements made by physicians. Androgenic side effects (greasy skin, acne, and increased growth of body hair) were more common during the DHEA treatment period (p = 0.02). CONCLUSION: DHEA does not improve quality of life, pain, fatigue, cognitive function, mood, or functional impairment in FM.