Hematoma extradural da fossa posterior: relato de sete casos

Hematomas da fossa posterior são complicação incomum de traumatismo cra-nioencefálico. Quase invariavelmente eles ocorrem após traumatismo da região occipital e estão associados com fraturas de crânio. O diagnóstico e tratamento dessa patologia tem sido grandemente favorecido pela tomografia computadorizada. Na presente série, a maioria dos pacientes teve evolução aguda, indicando o risco potencial de um tratamento conservador. Nossos resultados (29% de mortalidade) são similares àqueles previamente relatados para outras séries dessas lesões

Hopanoid lipids: from membranes to plant–bacteria interactions

International audienceLipid research represents a frontier for microbiology, as showcased by hopanoid lipids. Hopanoids, which resemble sterols and are found in the membranes of diverse bacteria, have left an extensive molecular fossil record. They were first discovered by petroleum geologists. Today, hopanoid-producing bacteria remain abundant in various ecosystems, such as the rhizosphere. Recently, great progress has been made in our understanding of hopanoid biosynthesis, facilitated in part by technical advances in lipid identification and quantification. A variety of genetically tractable, hopanoid-producing bacteria have been cultured, and tools to manipulate hopanoid biosynthesis and detect hopanoids are improving. However, we still have much to learn regarding how hopanoid production is regulated, how hopanoids act biophysically and biochemically, and how their production affects bacterial interactions with other organisms, such as plants. The study of hopanoids thus offers rich opportunities for discovery