Crystal Structure of a Yeast Aquaporin at 1.15 Å Reveals a Novel Gating Mechanism

Atomic-resolution X-ray crystallography, functional analyses, and molecular dynamics simulations suggest a novel mechanism for the regulation of water flux through the yeast Aqy1 water channel

The Gracilis Myocutaneous Free Flap: A Quantitative Analysis of the Fasciocutaneous Blood Supply and Implications for Autologous Breast Reconstruction

BACKGROUND: Mastectomies are one of the most common surgical procedures in women of the developed world. The gracilis myocutaneous flap is favoured by many reconstructive surgeons due to the donor site profile and speed of dissection. The distal component of the longitudinal skin paddle of the gracilis myocutaneous flap is unreliable. This study quantifies the fasciocutaneous vascular territories of the gracilis flap and offers the potential to reconstruct breasts of all sizes. METHODS: Twenty-seven human cadaver dissections were performed and injected using lead oxide into the gracilis vascular pedicles, followed by radiographic studies to identify the muscular and fasciocutaneous perforator patterns. The vascular territories and choke zones were characterized quantitatively using the 'Lymphatic Vessel Analysis Protocol' (LVAP) plug-in for Image J® software. RESULTS: We found a step-wise decrease in the average vessel density from the upper to middle and lower thirds of both the gracilis muscle and the overlying skin paddle with a significantly higher average vessel density in the skin compared to the muscle. The average vessel width was greater in the muscle. Distal to the main pedicle, there were either one (7/27 cases), two (14/27 cases) or three (6/27 cases) minor pedicles. The gracilis angiosome was T-shaped and the maximum cutaneous vascular territory for the main and first minor pedicle was 35 × 19 cm and 34 × 10 cm, respectively. CONCLUSION: Our findings support the concept that small volume breast reconstructions can be performed on suitable patients, based on septocutaneous perforators from the minor pedicle without the need to harvest any muscle, further reducing donor site morbidity. For large reconstructions, if a 'T' or tri-lobed flap with an extended vertical component is needed, it is important to establish if three territories are present. Flap reliability and size may be optimized following computed tomographic angiography and surgical delay

Riquetsioses no Brasil e Portugal: ocorrência, distribuição e diagnóstico Rickettsial diseases in Brazil and Portugal: occurrence, distribution and diagnosis

O presente artigo é uma atualização sobre a ocorrência e diagnóstico das riquetsioses existentes no Brasil e Portugal, com o objetivo de incentivar e incrementar a vigilância epidemiológica dessas doenças nos dois países. Realizou-se levantamento bibliográfico e foram apresentados dados não publicados de laboratórios e serviços de epidemiologia. Os resultados descreveram a ocorrência das riquetsioses no Brasil e Portugal, inclusive aquelas recém-descritas, advindas de riquétsias de potencial patogênico ainda incerto. Os métodos diagnósticos atualmente empregados foram discutidos. Como em outros países, as riquetsioses parecem assumir crescente importância em saúde pública. Relegadas a um plano secundário por muitas décadas, o interesse por essas infecções tem aumentado nos dois países, mas ainda carece de investigação para esclarecer seu real significado em saúde pública.<br>The present study is an update review on the occurrence and diagnosis of rickettsial diseases in Brazil and Portugal, aiming at promoting their epidemiological surveillance in both countries. A literature review was carried out and unpublished data of laboratories and surveillance systems were presented. The results described the occurrence of rickettsial diseases and infections in Brazil and Portugal, including other new and still poorly understood rickettsial infections. Current diagnostic methods were discussed. As in many other countries, rickettsial diseases and infections seem to be an emerging public health problem. Treated as a minor problem for many decades, the interest in these infections has increased in both countries but further studies are needed to establish their role as a public health problem