Mixotrophy in cyanobacteria.

Cyanobacteria evolved the oxygenic photosynthesis to generate organic matter from CO2 and sunlight, and they were responsible for the production of oxygen in the Earth's atmosphere. This made them a model for photosynthetic organisms, since they are easier to study than higher plants. Early studies suggested that only a minority among cyanobacteria might assimilate organic compounds, being considered mostly autotrophic for decades. However, compelling evidence from marine and freshwater cyanobacteria, including toxic strains, in the laboratory and in the field, has been obtained in the last decades: by using physiological and omics approaches, mixotrophy has been found to be a more widespread feature than initially believed. Furthermore, dominant clades of marine cyanobacteria can take up organic compounds, and mixotrophy is critical for their survival in deep waters with very low light. Hence, mixotrophy seems to be an essential trait in the metabolism of most cyanobacteria, which can be exploited for biotechnological purposes.

Biophysical characterization of microbial rhodopsins with DSE motif.

Microbial rhodopsins are photoreceptive transmembrane proteins that transport ions or regulate other intracellular biological processes. Recent genomic and metagenomic analyses found many microbial rhodopsins with unique sequences distinct from known ones. Functional characterization of these new types of microbial rhodopsins is expected to expand our understanding of their physiological roles. Here, we found microbial rhodopsins having a DSE motif in the third transmembrane helix from members of the Actinobacteria. Although the expressed proteins exhibited blue-green light absorption, either no or extremely small outward H+ pump activity was observed. The turnover rate of the photocycle reaction of the purified proteins was extremely slow compared to typical H+ pumps, suggesting these rhodopsins would work as photosensors or H+ pumps whose activities are enhanced by an unknown regulatory system in the hosts. The discovery of this rhodopsin group with the unique motif and functionality expands our understanding of the biological role of microbial rhodopsins.

Enfermedad inflamatoria pélvica: una causa inusual de obstrucción intestinal aguda / Pelvic inflammatory disease: An unusual cause of acute intestinal obstruction

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Evaluación de desempeño de los odontologos del Distrito de Salud Nº1 de la ciudad de La Paz, como instrumento para disminución de prevalencia de caries / Evaluation of performance of the dentists of the Health District Nº1 of the city of La Paz, as instrument for reduction of prevalence of caries

El presente trabajo tiene por objeto la evaluación del desempeño, para los odontologos del distrito de salud Nª1 noreste de la ciudad de La Paz, como instrumento para la disminución del índice de caries. A través de este instrumento es, se puede medir el desempeño en la labor asistencial de los odontólogos del distrito 1 noroeste de salud el 1er semestre del 2000 para relacionar con el 1er semestre del 2001, mediante el consolidado de información de coberturas de consultas nuevas en relación a obturaciones y consultas nuevas en relación a fluorizaciones que puedan disminuir el indice CPOD y ceo. Se realiza una descripción del contexto en la Ciudad de La Paz, de la ubicación de la red noroeste de salud, se encuentra en la parte norte de la ciudad...