Molecular and lipid biomarker analysis of a gypsum-hosted endoevaporitic microbial community.

Modern evaporitic microbial ecosystems are important analogs for understanding the record of earliest life on Earth. Although mineral-depositing shallow-marine environments were prevalent during the Precambrian, few such environments are now available today for study. We investigated the molecular and lipid biomarker composition of an endoevaporitic gypsarenite microbial mat community in Guerrero Negro, Mexico. The 16S ribosomal RNA gene-based phylogenetic analyses of this mat corroborate prior observations indicating that characteristic layered microbial communities colonize gypsum deposits world-wide despite considerable textural and morphological variability. Membrane fatty acid analysis of the surface tan/orange and lower green mat crust layers indicated cell densities of 1.6 × 10(9) and 4.2 × 10(9)  cells cm(-3) , respectively. Several biomarker fatty acids, ∆7,10-hexadecadienoic, iso-heptadecenoic, 10-methylhexadecanoic, and a ∆12-methyloctadecenoic, correlated well with distributions of Euhalothece, Stenotrophomonas, Desulfohalobium, and Rhodobacterales, respectively, revealed by the phylogenetic analyses. Chlorophyll (Chl) a and cyanobacterial phylotypes were present at all depths in the mat. Bacteriochlorophyl (Bchl) a and Bchl c were first detected in the oxic-anoxic transition zone and increased with depth. A series of monomethylalkanes (MMA), 8-methylhexadecane, 8-methylheptadecane, and 9-methyloctadecane were present in the surface crust but increased in abundance in the lower anoxic layers. The MMA structures are similar to those identified previously in cultures of the marine Chloroflexus-like organism 'Candidatus Chlorothrix halophila' gen. nov., sp. nov., and may represent the Bchl c community. Novel 3-methylhopanoids were identified in cultures of marine purple non-sulfur bacteria and serve as a probable biomarker for this group in the lower anoxic purple and olive-black layers. Together microbial culture and environmental analyses support novel sources for lipid biomarkers in gypsum crust mats.

Detection of Brevipalpus-transmitted viruses in their mite vectors by RT-PCR.

The diagnosis of plant diseases caused by Brevipalpus-transmitted viruses (BrTVs) has been done through the analyses of symptoms, transmission electron microscopy, and RT-PCR of infected plant tissues. Here, we report the detection of Citrus leprosis virus C, Orchid fleck virus, Clerodendrum chlorotic spot virus and Solanum violaefolium ringspot virus in their viruliferous vectors Brevipalpus spp. using specific primer pairs for each of the viruses. The efficiency of virus transmission by Brevipalpus mites is low, so the detection of these pathogens in their vectors could constitute an important tool for studies involving virus-vector relationships, transmission, and monitoring the pathogen prior to the appearance of symptoms in the field.

[Contribution to nursing care for patients with mitral valve disease]. / Subsídios para a assistência de enfermagem a pacientes com valvopatia mitral.

The purpose of this study was to define: the profile of patients with mitral valve dysfunction (stenosis and/or insufficiency) who were assisted at the University Outpatients' Clinic, the knowledge that these patients had concerning their disorder and the main difficulties and limitations resulting from it. The necessary data were obtained by interviewing 29 patients from November 1997 to February 1998. An analysis was conducted through the Content Analysis Technique. The results obtained helped to understand the problem under the individual's and his family's viewpoint, which helped to elaborate a nursing care program with an educational focus.

[Ambulatory nursing care for patients with aortic valve disease]. / Levantamento de subsídios para assistência de enfermagem ambulatorial a pacientes portadores de valvopatia aórtica.

This study aimed at characterizing the profile of outpatients with aortic valve dysfunction, identifying their knowledge about the disease, their major limitations during everyday activities and their means of coping with their predicament. The data obtained by semi-structured interviews with 12 patients and analyzed by quantitative and qualitative methods enabled to identify how the patients perceive the illness and the treatment as well as the implications to their everyday activities, that is, they allowed to capture reality from the subject's perspective, which is the knowledge for the elaboration of an educational proposal.