Trophic Garnishes: Cat–Rat Interactions in an Urban Environment

BACKGROUND:Community interactions can produce complex dynamics with counterintuitive responses. Synanthropic community members are of increasing practical interest for their effects on biodiversity and public health. Most studies incorporating introduced species have been performed on islands where they may pose a risk to the native fauna. Few have examined their interactions in urban environments where they represent the majority of species. We characterized house cat (Felis catus) predation on wild Norway rats (Rattus norvegicus), and its population effects in an urban area as a model system. Three aspects of predation likely to influence population dynamics were examined; the stratum of the prey population killed by predators, the intensity of the predation, and the size of the predator population. METHODOLOGY/PRINCIPAL FINDINGS:Predation pressure was estimated from the sizes of the rat and cat populations, and the characteristics of rats killed in 20 alleys. Short and long term responses of rat population to perturbations were examined by removal trapping. Perturbations removed an average of 56% of the rats/alley but had no negative long-term impact on the size of the rat population (49.6+/-12.5 rats/alley and 123.8+/-42.2 rats/alley over two years). The sizes of the cat population during two years (3.5 animals/alley and 2.7 animals/alley) also were unaffected by rat population perturbations. Predation by cats occurred in 9/20 alleys. Predated rats were predominantly juveniles and significantly smaller (144.6 g+/-17.8 g) than the trapped rats (385.0 g+/-135.6 g). Cats rarely preyed on the larger, older portion of the rat population. CONCLUSIONS/SIGNIFICANCE:The rat population appears resilient to perturbation from even substantial population reduction using targeted removal. In this area there is a relatively low population density of cats and they only occasionally prey on the rat population. This occasional predation primarily removes the juvenile proportion of the rat population. The top predator in this urban ecosystem appears to have little impact on the size of the prey population, and similarly, reduction in rat populations doesn't impact the size of the cat population. However, the selected targeting of small rats may locally influence the size structure of the population which may have consequences for patterns of pathogen transmission

Deep Sequencing of the Vaginal Microbiota of Women with HIV

BACKGROUND: Women living with HIV and co-infected with bacterial vaginosis (BV) are at higher risk for transmitting HIV to a partner or newborn. It is poorly understood which bacterial communities constitute BV or the normal vaginal microbiota among this population and how the microbiota associated with BV responds to antibiotic treatment. METHODS AND FINDINGS: The vaginal microbiota of 132 HIV positive Tanzanian women, including 39 who received metronidazole treatment for BV, were profiled using Illumina to sequence the V6 region of the 16S rRNA gene. Of note, Gardnerella vaginalis and Lactobacillus iners were detected in each sample constituting core members of the vaginal microbiota. Eight major clusters were detected with relatively uniform microbiota compositions. Two clusters dominated by L. iners or L. crispatus were strongly associated with a normal microbiota. The L. crispatus dominated microbiota were associated with low pH, but when L. crispatus was not present, a large fraction of L. iners was required to predict a low pH. Four clusters were strongly associated with BV, and were dominated by Prevotella bivia, Lachnospiraceae, or a mixture of different species. Metronidazole treatment reduced the microbial diversity and perturbed the BV-associated microbiota, but rarely resulted in the establishment of a lactobacilli-dominated microbiota. CONCLUSIONS: Illumina based microbial profiling enabled high though-put analyses of microbial samples at a high phylogenetic resolution. The vaginal microbiota among women living with HIV in Sub-Saharan Africa constitutes several profiles associated with a normal microbiota or BV. Recurrence of BV frequently constitutes a different BV-associated profile than before antibiotic treatment

Reeducação postural global e alongamento estático segmentar na melhora da flexibilidade, força muscular e amplitude de movimento: um estudo comparativo

Exercícios de alongamento são usados para aumentar a flexibilidade e amplitude de movimento (ADM). Entre os métodos existentes, destacam-se a reeducação postural global (RPG), que promove o alongamento global das cadeias musculares, e o alongamento segmentar, que alonga um músculo ou grupo muscular específico. Este estudo visou comparar o alongamento segmentar e o global pela técnica de RPG quanto ao ganho de flexibilidade, ADM e força muscular. Trinta mulheres foram distribuídas aleatoriamente em três grupos (n=10 em cada): o grupo global fez alongamento de cadeias musculares; o grupo segmentar realizou alongamento segmentar; e o grupo controle não fez alongamento. Antes e depois do tratamento, em todos os grupos, foram avaliadas a ADM de extensão da perna, flexibilidade pelo teste 3o dedo-solo e força isométrica de flexão da perna em 45° e 90°. Os dois grupos experimentais realizaram oito sessões de alongamento de 30 minutos cada, duas vezes por semana. Toda a análise estatística foi realizada com pStretching exercises are prescribed to increase flexibility and range of motion (ROM). Two current stretching methods are the global posture reeducation (GPR), where muscle chains are stretched, and segmentary exercises, where a single muscle or muscle group is stretched. The aim of this study was to compare these two techniques, assessing their effects on improving flexibility, ROM and muscle strength. Thirty women were randomly distributed into three groups (n=10 each): global group performed stretching following GPR method; segment group performed segment stretching exercises; and control group did no exercise. Before and after treatment, in all groups, knee extension ROM, flexibility by means of the fingertip-to-floor test, and isometric muscular strength at 45° and 90° knee flexion were measured. Each treated group performed eight stretching 30-minute sessions for four weeks, twice a week. Data were statistically analysed and the significance level set at p<0.05. Global and segment group results were similar and better than control group's concerning ROM, flexibility and muscle strength at 45° and 90° knee flexion (p<0.05). When assessing improvement inter-sessions, both groups had better ROM improvement at the first sessions, decreasing along the others. Both global and segmentary stretching techniques were hence found effective in improving flexibility, ROM and leg muscle strength