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Introdução: A dormência é caracterizada pela incapacidade de sementes viáveis germinarem em condições favoráveis, sendo causada por fatores genéticos e/ou ambientais. A mamona (Ricinus communis Linné), cuja dormência não apresenta causa definida, é uma planta da família Euphorbiaceae. O óleo extraído de suas sementes apresenta diversas caraterísticas interessantes para aplicação industrial, sendo comercializado com alto valor agregado. Objetivo: Este estudo tem como objetivo investigar as causas da dormência em sementes de mamona e identificar genes relacionados ao fenômeno. Materiais e métodos: Inicialmente realizamos uma revisão de literatura para identificar genes relacionados a dormência em Arabidopsis thaliana, e então uma busca pelas sequências proteicas no banco de dados do TAIR. Após a seleção dos genes, utilizamos o banco de dados Phytozome para realizar um BLASTP no genoma de mamona, selecionando as sequências homólogas. Com a seleção das sequências, realizamos uma análise filogenética para montagem de árvore NJ e análise de motifs, identificando genes relacionados à dormência em mamona. Em seguida, realizamos uma curva de embebição com sementes escarificadas e não-escarificadas da Cultivar BRS Energia, que apresenta dormência, para verificar se o tegumento representa uma barreira à absorção de água. Paralelamente, preparamos extrato aquoso do tegumento, que foi utilizado em ensaio para verificar seu efeito sobre a germinação de sementes de alface. Resultados: Na análise filogenética, foram identificados 17 genes homólogos aos genes relacionados à dormência em Arabidopsis, indicando a possibilidade de dormência fisiológica na mamona. A curva de embebição demonstrou que as sementes dormentes atingem a fase II de embebição, descartando-se a possibilidade de dormência física. O extrato possuiu efeito inibitório na germinação de sementes de alface, que é atribuída a substâncias presentes no tegumento. Conclusão: Os resultados obtidos indicam a possibilidade de dormência fisiológica/química nas sementes de Ricinus communis. Com esse trabalho, esperamos contribuir em futuros estudos voltados à dormência na espécie.

Ricinus communis L. is an important oilseed crop species which is mostly cultivated in Brazil by family farmers in the northeastern semiarid region. This species is renowned by the quality and properties of the oil extracted from its seeds, which can be used for a diverse range of industrial applications. Furthermore, this species is considered to be tolerant to abiotic stresses such as drought stress. The use of post-harvest and pre-germination treatments on mature seeds can enhance their viability and vigor. In this context, the objective of this study was to investigate the effect of osmoconditioning on R. communis L. seed germinability parameters and events related to the reactivation of cell cycle, i.e . tubulin accumulation and microtubular cytoskeleton configurations. Osmoconditioning was applied to both fresh-harvested (FH) and dry seeds (DS), originating fresh-harvested osmoconditioned (FHO) and dry osmoconditioned (DO) seeds. In general, osmoconditioning promoted seed priming by enhancing seed germinability of FHO and DO seeds by means of better germination speed and uniformity, except for a decrease of uniformity in FHO seeds. Immunocytochemical and immunohistochemical analysis revealed an increasing accumulation of tubulin in FHO and DO seeds, followed by the accumulation of tubulin granules in DO seeds. Mitotic microtubules were only visible in FHO and DO seeds after radicle protrusion and, therefore, seed germination occurred solely by cell elongation, whereas FH and DS seeds required cell cycle reactivation and cell proliferation during imbibition, i.e . prior to radicle protrusion or germination per se . The prompt activation of microtubular cytoskeleton synthesis in seeds that were osmoconditioned might be a possible strategy of the species for faster and more uniform and vigorous seed germination and seedling establishment and, therefore, better survival during periods of drought in harsh environments. These findings provide important insights into the mechanism underlying plant adaptation to harsh environmental conditions, which would be very helpful to develop germination and seedling production protocols to obtain faster and more vigorous and uniform germination seedling stand for the sustainable exploitation of R. communis by small family farmers under the typical harsh conditions of the semiarid regions worldwide.

The newly described Streptococcus pneumoniae serotype 6C accounted for 2.3% (16/709) of meningitis cases and 3.2% (3/95) of nasopharyngeal isolates from healthy individuals in Brazil. The strains were multidrug resistant (18.8%) and genetically diverse. Despite low serotype 6C prevalence, continuous surveillance is necessary to guide vaccine strategies.

SummaryBackgroundOver recent decades, a resurgence of invasive group A streptococcal (GAS) infections has been observed; GAS remains a rare cause of pyogenic meningitis. We report herein population-based findings of long-term surveillance for GAS meningitis in Salvador, Brazil, and estimate the overall burden of invasive GAS infections.MethodsFrom February 1996 to February 2007 we conducted active surveillance for GAS meningitis in the state reference hospital for infectious diseases in Salvador, Brazil. Data on clinical presentation, laboratory records, and outcome were collected through interviews and chart review. GAS isolates were evaluated for antimicrobial susceptibility and emm type.ResultsWe identified 20 cases of GAS meningitis, which accounted for 0.9% of all culture-proven bacterial meningitis in the study period. The mean annual incidence of GAS meningitis was 0.03 cases per 100000 population in metropolitan Salvador and peaked in children

Background Few studies of dengue have shown group-level associations between demographic, socioeconomic, or geographic characteristics and the spatial distribution of dengue within small urban areas. This study aimed to examine whether specific characteristics of an urban slum community were associated with the risk of dengue disease. Methodology/Principal Findings From 01/2009 to 12/2010, we conducted enhanced, community-based surveillance in the only public emergency unit in a slum in Salvador, Brazil to identify acute febrile illness (AFI) patients with laboratory evidence of dengue infection. Patient households were geocoded within census tracts (CTs). Demographic, socioeconomic, and geographical data were obtained from the 2010 national census. Associations between CTs characteristics and the spatial risk of both dengue and non-dengue AFI were assessed by Poisson log-normal and conditional auto-regressive models (CAR). We identified 651 (22.0%) dengue cases among 2,962 AFI patients. Estimated risk of symptomatic dengue was 21.3 and 70.2 cases per 10,000 inhabitants in 2009 and 2010, respectively. All the four dengue serotypes were identified, but DENV2 predominated (DENV1: 8.1%; DENV2: 90.7%; DENV3: 0.4%; DENV4: 0.8%). Multivariable CAR regression analysis showed increased dengue risk in CTs with poorer inhabitants (RR: 1.02 for each percent increase in the frequency of families earning ≤1 times the minimum wage; 95% CI: 1.01-1.04), and decreased risk in CTs located farther from the health unit (RR: 0.87 for each 100 meter increase; 95% CI: 0.80-0.94). The same CTs characteristics were also associated with non-dengue AFI risk. Conclusions/Significance This study highlights the large burden of symptomatic dengue on individuals living in urban slums in Brazil. Lower neighborhood socioeconomic status was independently associated with increased risk of dengue, indicating that within slum communities with high levels of absolute poverty, factors associated with the social gradient influence dengue transmission. In addition, poor geographic access to health services may be a barrier to identifying both dengue and non-dengue AFI cases. Therefore, further spatial studies should account for this potential source of bias., Author Summary Dengue is influenced by the environment; however, few studies have investigated the relationship between neighborhood characteristics and the spatial distribution of dengue within small urban areas. We examined whether specific characteristics of an urban slum community were associated with dengue risk. From January 2009 to December 2010, we conducted community-based surveillance in a slum in Salvador, Brazil to identify patients with acute febrile illness (AFI) and to test them for dengue. We identified 651 (22.0%) patients with laboratory evidence of dengue infection among 2,962 AFI patients. All the four dengue serotypes were detected, but DENV2 predominated (DENV1 8.1%; DENV2 90.7%; DENV3 0.4%; DENV4 0.8%). Estimated risk of symptomatic dengue was 21.3 and 70.2 cases per 10,000 inhabitants in 2009 and 2010, respectively. We found that neighborhood poverty level and proximity to the health center were associated with higher risk of detection of dengue and other AFI. This study highlights the large burden of dengue in poor urban slums of Brazil and indicates that socioeconomic development could potentially mitigate risk factors for both dengue and non-dengue AFI cases. In addition, we found that residential proximity to a health care facility was associated with improved case detection. Therefore, further studies on disease distribution should consider household proximity to health care facilities when assessing risk.

Fetal hemoglobin (HbF), encoded by the HBG2 and HBG1 genes, is the best-known genetic modulator of sickle cell anemia, varying dramatically in concentration in the blood of these patients. This variation is partially associated with polymorphisms located in the promoter region of the HBG2 and HBG1 genes. In order to explore known and unknown polymorphisms in these genes, the sequences of their promoter regions were screened in sickle cell anemia patients and correlated with both their HbF levels and their betaS-globin haplotypes. Additionally, the sequences were compared with genes from 2 healthy groups, a reference one (N = 104) and an Afro-descendant one (N = 98), to identify polymorphisms linked to the ethnic background.The reference group was composed by healthy individuals from the general population. Four polymorphisms were identified in the promoter region of HBG2 and 8 in the promoter region of HBG1 among the studied groups. Four novel single nucleotide polymorphisms (SNP) located at positions -324, -317, -309 and -307 were identified in the reference group. A deletion located between -396 and -391 in the HBG2 promoter region and the SNP -271 C--T in the HBG1 promoter region were associated with the Central African Republic betaS-globin haplotype. In contrast, the -369 C--G and 309 A--G SNPs in the HBG2 promoter region were correlated to the Benin haplotype. The polymorphisms -396_-391 del HBG2, -369 SNP HBG2 and -271 SNP HBG1 correlated with HbF levels. Hence, we suggest an important role of HBG2 and HBG1 gene polymorphisms on the HbF synthesis.