The Microbiome of Brazilian Mangrove Sediments as Revealed by Metagenomics

Here we embark in a deep metagenomic survey that revealed the taxonomic and potential metabolic pathways aspects of mangrove sediment microbiology. The extraction of DNA from sediment samples and the direct application of pyrosequencing resulted in approximately 215 Mb of data from four distinct mangrove areas (BrMgv01 to 04) in Brazil. The taxonomic approaches applied revealed the dominance of Deltaproteobacteria and Gammaproteobacteria in the samples. Paired statistical analysis showed higher proportions of specific taxonomic groups in each dataset. The metabolic reconstruction indicated the possible occurrence of processes modulated by the prevailing conditions found in mangrove sediments. In terms of carbon cycling, the sequences indicated the prevalence of genes involved in the metabolism of methane, formaldehyde, and carbon dioxide. With respect to the nitrogen cycle, evidence for sequences associated with dissimilatory reduction of nitrate, nitrogen immobilization, and denitrification was detected. Sequences related to the production of adenylsulfate, sulfite, and H2S were relevant to the sulphur cycle. These data indicate that the microbial core involved in methane, nitrogen, and sulphur metabolism consists mainly of Burkholderiaceae, Planctomycetaceae, Rhodobacteraceae, and Desulfobacteraceae. Comparison of our data to datasets from soil and sea samples resulted in the allotment of the mangrove sediments between those samples. The results of this study add valuable data about the composition of microbial communities in mangroves and also shed light on possible transformations promoted by microbial organisms in mangrove sediments.

Quantitation of malondialdehyde in gingival crevicular fluid by a high-performance liquid chromatography-based method

Lipid peroxidation (LPO) has been associated with periodontal disease, and the evaluation of malondialdehyde (MDA) in the gingival crevicular fluid (GCF), an inflammatory exudate from the surrounding tissue of the periodontium, may be useful to clarify the role of LPO in the pathogenesis of periodontal disease. We describe the validation of a method to measure MDA in the GCF using high-performance liquid chromatography. MDA calibration curves were prepared with phosphate-buffered solution spiked with increasing known concentrations of MDA. Healthy and diseased GCF samples were collected from the same patient to avoid interindividual variability. MDA response was linear in the range measured, and excellent agreement was observed between added and detected concentrations of MDA. Samples' intra- and interday coefficients of variation were below 6.3% and 12.4%, respectively. The limit of quantitation (signal/noise = 5) was 0.03 mu M. When the validated method was applied to the GCF, excellent agreement was observed in the MDA quantitation from healthy and diseased sites, and diseased sites presented more MDA than healthy sites (P < 0.05). In this study, a validated method for MDA quantitation in GCF was established with satisfactory sensitivity, precision, and accuracy. (C) 2012 Elsevier Inc. All rights reserved.

Evaluation of tropical water sources and mollusks in southern Brazil using microbiological, biochemical, and chemical parameters

Florianopolis, a city located in the Santa Catarina State in southern Brazil, is the national leading producer of bivalve mollusks. The quality of bivalve mollusks is closely related to the sanitary conditions of surrounding waters where they are cultivated. Presently, cultivation areas receive large amounts of effluents derived mainly from treated and non-treated domestic, rural, and urban sewage. This contributes to the contamination of mollusks with trace metals, pesticides, other organic compounds, and human pathogens such as viruses, bacteria, and protozoan. The aim of this study was to perform a thorough diagnosis of the shellfish growing areas in Florianopolis, on the coast of Santa Catarina. The contamination levels of seawater, sediments, and oysters were evaluated for their microbiological, biochemical, and chemical parameters at five sea sites in Florianopolis, namely three regular oyster cultivation areas (Sites 1, 2, and oyster supplier), a polluted site (Site 3), and a heavily polluted site (Site 4). Samples were evaluated at day zero and after 14 days. Seawater and sediment samples were collected just once, at the end of the experiment. Antioxidant defenses, which may occur in contaminated environments in response to the increased production of reactive oxygen species (ROS) by organisms, were analyzed in oysters, as well as organic compounds (in oysters and sediment samples) and microbiological contamination (in oysters and seawater samples). The results showed the presence of the following contaminants: fecal coliforms in seawater samples (four sites), human adenovirus (all sites), human noroviruses GI and GII (two sites), Hepatitis A viruses (one site), JC Polyomavirus in an oyster sample from the oyster supplier, Giardia duodenalis cysts, and Cryptosporidium sp oocysts (one site). Among organochlorine pesticides, only DDT (dichlorodiphenyltrichloroethane) and HCH (hexachlorocyclohexane) were detected in some sediment and oysters samples in very low levels; site 4 had the highest concentrations of total aliphatic hydrocarbons. PAHs, and linear alkylbenzenes (LABs) found either in oysters or in sediment samples. The major concentration of fecal sterol coprostanol was found at site 4, followed by site 3. After 14 days of allocation in the four selected sites, there was a significant difference in the enzymes analyzed at the monitored spots. The detection of different contaminants in oysters, seawater, and sediment samples in the present study shows the impact untreated or inadequately treated effluents have on coastal areas. These results highlight the need for public investment in adequate wastewater treatment and adequate treatment of oysters, ensuring safe areas for shellfish production as well as healthier bivalve mollusks for consumption.

Peat palynomorphs from Eugenio de Melo, middle valley of Paraiba do Sul River, Sao Paulo, Brazil.

Peat palynomorphs from Eugenio de Melo, middle valley of Paraiba do Sul River, Sao Paulo, Brazil. This paper presents palynomorphs identified in the peats of the Eugenio de Melo region, the middle valley of the Paraiba do Sul River, Sao Paulo State. The samples were collected at intervals of 10 cm from a core with 3.90 m deep, aged between 11400-11220 and 490-290 cal. years B.P. Three types of algae were identified and presented, and ten spores, two gymnosperm pollen grains and thirty-nine angiosperms were described, with their own ecological information.

Anatomical and ultrastructural analyses of in vitro organogenesis from root explants of commercial passion fruit (Passiflora edulis Sims)

This study aimed to characterize the anatomical events and ultrastructural aspects of direct and indirect in vitro organogenesis in Passiflora edulis. Root explants were cultured on induction medium, supplemented with 4.44 mu M 6-benzyladenine. Roots at different stages of development were collected and processed for observation by light microscopy and scanning and transmission electron microscopy. Patterns of direct and indirect regeneration were observed in the explants. During direct organogenesis, the organogenic buds and nodules, formed from meristemoids, originated from the pericycle regions distant from the cut surface. Completely differentiated buds were observed after 20 days of culture. During indirect organogenesis, bud formation occurred via meristemoids at the periphery of the calli, which differentiated from the cortical region of the initial explant. Regardless of the regeneration pattern, the meristemoids had similar ultrastructural characteristics; however, differences were reported in the nuclear shape of the cells of the meristemoids formed directly and indirectly. This study provides important information for enhancing the understanding and characterization of the organogenic process in non-meristematic explants and provides information on the use of roots as explants in genetic transformation protocols for this important tropical species.

Facial Profile Evaluation of Isolated Pierre Robin Sequence

Objective: To evaluate numerically the facial profile of children with isolated Pierre Robin sequence (PRS) and to compare them with a control group that has no pathologies and exhibits regular and balanced facial growth, with no skeletal alterations. Patients: Eighty-three children aged 5 to 10 years (PRS group, n = 60; control group, n = 23) were selected. Setting: Hospital for Rehabilitation of Craniofacial Anomalies, University of Sao Paulo (HRAC-USP). Children from the control group were taken from the program of Interceptive Orthodontics at HRAC-USP. Design: Angular and ratio analyses of the facial profiles in both groups were realized through digital photographs. The PRS group was subdivided into two groups-complete and incomplete-according to the sagittal extension of the cleft palate, to investigate the possible influence of cleft extension on the face. Results: The facial convexity angle and the facial inferior third angle were considerably higher in the PRS groups than in the control group and were not significantly different between PRS groups. Nasolabial angle did not differ between groups. Conclusion: The facial profile was more convex in individuals with PRS than in those with regular facial growth and with no pathology. The mandible was responsible for the convexity of the profile in PRS because of its lack off anterior projection. An important relationship between the extension of the cleft palate and alterations in facial profile in PRS was not observed.

Somatic embryogenesis of a wild passion fruit species Passiflora cincinnata Masters: histocytological and histochemical evidences

The characterization of cellular changes that occur during somatic embryogenesis is essential for understanding the factors involved in the transition of somatic cells into embryogenically competent cells and determination of cells and/or tissues involved. The present study describes the anatomical and ultrastructural events that lead to the formation of somatic embryos in the model system of the wild passion fruit (Passiflora cincinnata). Mature zygotic embryos were inoculated in Murashige and Skoog induction media supplemented with 2,4-dichlorophenoxyacetic acid and 6-benzyladenine. Zygotic embryo explants at different development stages were collected and processed by conventional methods for studies using light, scanning, and transmission electron microscopy (TEM). Histochemical tests were used to examine the mobilization of reserves. The differentiation of the somatic embryos began in the abaxial side of the cotyledon region. Protuberances were formed from the meristematic proliferation of the epidermal and mesophyll cells. These cells had large nuclei, dense cytoplasm with a predominance of mitochondria, and a few reserve compounds. The protuberances extended throughout the abaxial surface of the cotyledons. The ongoing differentiation of peripheral cells of these structures led to the formation of proembryogenic zones, which, in turn, dedifferentiated into somatic embryos of multicellular origin. In the initial stages of embryogenesis, the epidermal and mesophyll cells showed starch grains and less lipids and protein reserves than the starting explant. These results provide detailed information on anatomical and ultrastructural changes involved in the acquisition of embryogenic competence and embryo differentiation that has been lacking so far in Passiflora.

O canteiro do poeta-arquiteto: a conduta criativa de João Cabral de Melo Neto à luz de seus manuscritos

Neste artigo repensamos a metáfora do "poeta-engenheiro", ou "poeta-arquiteto", que geralmente caracteriza o processo criativo de João Cabral de Melo Neto, à luz de uma leitura genética de manuscritos de A educação pela pedra. Veremos que o "arquiteto" da metáfora provém da teoria de Le Corbusier, na qual o desenho (a concepção) determina o canteiro (a execução). No entanto, a análise de transformações de estruturas por meio de reformulações textuais nos manuscritos do poeta mostra que, por vezes, o projeto, ou intenção, se transforma nos trabalhos da página-canteiro.