177 research outputs found

    Avaliação da sensibilidade in vitro à quinidina em isolados brasileiros de Plasmodium falciparum: análise comparativa à quinina e à cloroquina

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    Malária falciparum representa grave e crescente problema de saúde pública mundial, dada a resistência do parasito à maioria dos fármacos disponíveis. Em algumas áreas endêmicas, a quinidina, diastereoisômero do antimalárico quinina, vem sendo empregada em substituição a este último. Com o objetivo de avaliar o emprego da quinidina como alternativa à perda crescente de sensibilidade de cepas brasileiras de P. falciparum à quinina, como o observado na região Amazônica, realizamos ensaio comparativo entre quinidina, quinina e cloroquina. A técnica in vitro do microteste de sensibilidade foi utilizada. Todos os isolados mostraram-se altamente resistentes à cloroquina. Resistência à quinina não foi observada, embora altos valores de CMI (concentração mínima inibitória) tenham sido encontrados. Estes resultados corroboram o decréscimo de suscetibilidade de cepas brasileiras à quinina. Observou-se variação de IC50 de 0,053 a 4,577 mimol/L de sangue para a quinidina, enquanto para a quinina estimou-se IC50 de 0,053 a 8,132 mimol/L de sangue. Ademais, observou-se clareamento da parasitemia em concentrações inferiores à da quinidina quando empregada como fármaco antiarrítmico, confirmando estudo anterior por nós realizado. Resultados semelhantes foram encontrados em isolado oriundo da África.Falciparum malaria represents a serious and an increasing world public health problem due to the acquired parasite's resistance to the most available drugs. In some endemic areas, quinidine, a diastereoisomer of the antimalarial quinine, has been employed for replacing the latter. In order to evaluate the use of quinidine as an alternative to the increasing loss of quinine effectiveness in Brazilian P. falciparum strains, as has been observed in the Amazon area, we have assayed quinidine, quinine and chloroquine. The in vitro microtechnique was employed. All isolates showed to be highly resistant to chloroquine. Resistance to quinine was not noted although high MIC (minimal inhibitory concentration) values have been observed. These data corroborate the decreasing sensitivity to quinine in strains from Brazil. Quinidine showed IC50 from 0.053 to 4.577 mumol/L of blood while IC50 from 0.053 to 8.132 mumol/L of blood was estimated for quinine. Moreover, clearance of the parasitemia was observed in concentrations lower than that used for quinidine in antiarrhythmic therapy, confirming our previous data. The results were similar to African isolate

    Physico-chemical characterization of inclusion complex between hydroxymethylnitrofurazone and hydroxypropyl-beta-cyclodextrin

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    Hydroxymethylnitrofurazone (NFOH) is a prodrug that is active against Trypanosoma cruzi. It however presents low solubility and high toxicity. Hydroxypropyl-beta-cyclodextrin (HP-beta-CD) can be used as a drug-delivery system for NFOH modifying its physico-chemical properties. The aim of this work is to characterize the inclusion complex between NFOH and HP-beta-CD. The rate of NFOH release decreases after complexation and thermodynamic parameters from the solubility isotherm studies revealed that a stable complex is formed (deltaGº= 1.7 kJ/mol). This study focuses on the physico-chemical characterization of a drug-delivery formulation that comes out as a potentially new therapeutic option for Chagas disease treatment.FAPESPCoordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES

    Theoretical and voltammetric studies of 5-Nitro-heterocyclic derivatives with potential trypanocidal activities

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    Stereoelectronic properties of nitro-heterocyclic bioisosteric congeners were investigated using theory-level quantum chemistry and cyclic voltammetry with the goal of determining physico-chemical properties that affect the redox potential of the nitro group. Molecular geometry, physicochemical properties and stereoelectronic surfaces, such as molecular electrostatic potential, and HOMO and LUMO orbitalar distributions, were calculated using the AM1 semiempirical method. The redox potential of nitro-heterocyclic compounds, which corresponds to the (Ar-NO2/Ar-NO2•- ) redox couple, was measured in aprotic media (DMSO and 0.1 mol L-1 Bu4NH4BF4) using glassy carbon as working electrode, Pt wire, Ag/AgCl, KCl(sat) as counter and reference electrodes, respectively. Analysis of minimal energy conformers of all derivatives indicated a break in structural planarity located between the hydrazine nitrogen and benzamide moiety. No statistical correlation was obtained using the PLS regression method, taking in account all physicochemical properties and the redox potential, which might result from the lack of coplanarity effect in the molecular structure of the compounds

    Women Are More Susceptible to Caries but Individuals Born with Clefts Are Not

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    The identification of individuals at a higher risk of developing caries is of great interest. Isolated forms of cleft lip and palate are among the most common craniofacial congenital anomalies in humans. Historically, several reports suggest that individuals born with clefts have a higher risk for caries. Caries continues to be the most common infectious noncontagious disease worldwide and a great burden to any health system. The identification of individuals of higher susceptibility to caries is of great interest. In this paper, we assessed caries experience of 1,593 individuals from three distinct populations. The study included individuals born with clefts, their unaffected relatives, and unrelated unaffected controls that were recruited from areas with similar cultural pressures and limited access to dental care. DMFT/dmft scores were obtained, and caries experience rates were compared among the three groups in each geographic area. Individuals born with clefts did not present higher caries experience in comparison to their unaffected relatives or unrelated unaffected controls. Women tend to present higher caries rates in comparison to men. Our work provides strong evidence that individuals born with clefts are not at higher risk to caries; however, women tend to have more severe caries experience

    Physico-chemical characterization of inclusion complex between hydroxymethylnitrofurazone and hydroxypropyl-b-cyclodextrin

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    Hydroxymethylnitrofurazone (NFOH) is a prodrug that is active against Trypanosoma cruzi. It however presents low solubility and high toxicity. Hydroxypropyl-b-cyclodextrin (HP-b-CD) can be used as a drug-delivery system for NFOH modifying its physico-chemical properties. The aim of this work is to characterize the inclusion complex between NFOH and HP-b-CD. The rate of NFOH release decreases after complexation and thermodynamic parameters from the solubility isotherm studies revealed that a stable complex is formed (DGº= 1.7 kJ/mol). This study focuses on the physico-chemical characterization of a drug-delivery formulation that comes out as a potentially new therapeutic option for Chagas disease treatment312290295COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP00019-08-0305/03045-9; 04/02091-4; 06/00787-

    Spatial distribution of Madeira Island Laurisilva endemic spiders (Arachnida: Araneae).

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    Madeira island presents a unique spider diversity with a high number of endemic species, many of which are still poorly known. A recent biodiversity survey on the terrestrial arthropods of the native forest, Laurisilva, provided a large set of standardized samples from various patches throughout the island. Out of the fifty two species recorded, approximately 33.3% are Madeiran endemics, many of which had not been collected since their original description. Two new species to science are reported ? Ceratinopsis n. sp. and Theridion n. sp. ? and the first records of Poeciloneta variegata (Blackwall, 1841) and Tetragnatha intermedia Kulczynski, 1891 are reported for the first time for Madeira island. Considerations on species richness and abundance from different Laurisilva locations are presented, together with distribution maps for endemic species. These results contribute to a better understanding of spider diversity patterns and endemic species distribution in the native forest of Madeira island

    Detection of Streptococcus mutans Genomic DNA in Human DNA Samples Extracted from Saliva and Blood

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    Caries is a multifactorial disease, and studies aiming to unravel the factors modulating its etiology must consider all known predisposing factors. One major factor is bacterial colonization, and Streptococcus mutans is the main microorganism associated with the initiation of the disease. In our studies, we have access to DNA samples extracted from human saliva and blood. In this report, we tested a real-time PCR assay developed to detect copies of genomic DNA from Streptococcus mutans in 1,424 DNA samples from humans. Our results suggest that we can determine the presence of genomic DNA copies of Streptococcus mutans in both DNA samples from caries-free and caries-affected individuals. However, we were not able to detect the presence of genomic DNA copies of Streptococcus mutans in any DNA samples extracted from peripheral blood, which suggests the assay may not be sensitive enough for this goal. Values of the threshold cycle of the real-time PCR reaction correlate with higher levels of caries experience in children, but this correlation could not be detected for adults

    Detection of Streptococcus mutans Genomic DNA in Human DNA Samples Extracted from Saliva and Blood

    Get PDF
    Caries is a multifactorial disease, and studies aiming to unravel the factors modulating its etiology must consider all known predisposing factors. One major factor is bacterial colonization, and Streptococcus mutans is the main microorganism associated with the initiation of the disease. In our studies, we have access to DNA samples extracted from human saliva and blood. In this report, we tested a real-time PCR assay developed to detect copies of genomic DNA from Streptococcus mutans in 1,424 DNA samples from humans. Our results suggest that we can determine the presence of genomic DNA copies of Streptococcus mutans in both DNA samples from caries-free and caries-affected individuals. However, we were not able to detect the presence of genomic DNA copies of Streptococcus mutans in any DNA samples extracted from peripheral blood, which suggests the assay may not be sensitive enough for this goal. Values of the threshold cycle of the real-time PCR reaction correlate with higher levels of caries experience in children, but this correlation could not be detected for adults

    Applying the Maternal Near Miss Approach for the Evaluation of Quality of Obstetric Care: A Worked Example from a Multicenter Surveillance Study

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    Objective. To assess quality of care of women with severe maternal morbidity and to identify associated factors. Method. This is a national multicenter cross-sectional study performing surveillance for severe maternal morbidity, using the World Health Organization criteria. the expected number of maternal deaths was calculated with the maternal severity index (MSI) based on the severity of complication, and the standardized mortality ratio (SMR) for each center was estimated. Analyses on the adequacy of care were performed. Results. 17 hospitals were classified as providing adequate and 10 as nonadequate care. Besides almost twofold increase in maternal mortality ratio, the main factors associated with nonadequate performance were geographic difficulty in accessing health services (P < 0.001), delays related to quality of medical care (P = 0.012), absence of blood derivatives (P = 0.013), difficulties of communication between health services (P = 0.004), and any delay during the whole process (P = 0.039). Conclusions. This is an example of how evaluation of the performance of health services is possible, using a benchmarking tool specific to Obstetrics. in this study the MSI was a useful tool for identifying differences in maternal mortality ratios and factors associated with nonadequate performance of care.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Univ Campinas UNICAMP, Sch Med Sci, Dept Obstet & Gynaecol, BR-13083881 Campinas, SP, BrazilCtr Res Reprod Hlth Campinas Cemicamp, BR-13083888 Campinas, SP, BrazilUniv Fed Amazonas, Manaus, Amazonas, BrazilSch Med Sci, CISAM, Recife, PE, BrazilUniv Fed Ceara, Fortaleza, Ceara, BrazilUniv Fed Bahia, Salvador, BA, BrazilHosp Geral Cesar Cals, Fortaleza, Ceara, BrazilHosp Geral Fortaleza, Fortaleza, Ceara, BrazilMaternidade Odete Valadares, Belo Horizonte, MG, BrazilHosp Materno Infantil, Goiania, Go, BrazilInst Materno Infantil Pernambuco, Recife, PE, BrazilUniv Fed Pernambuco, Recife, PE, BrazilUniv Fed Campina Grande, Campina Grande, PB, BrazilUniv Fed Maranhao, Sao Luis, MA, BrazilUniv Fed Parana, BR-80060000 Curitiba, Parana, BrazilUniv Fed Paraiba, BR-58059900 Joao Pessoa, Paraiba, BrazilHosp Maternidade Fernando Magalhaes, Rio de Janeiro, RJ, BrazilUniv Fed Rio Grande do Sul, Porto Alegre, RS, BrazilHosp Maternidade Celso Pierro, Campinas, SP, BrazilInst Fernandes Figueira Fiocruz, Rio de Janeiro, RJ, BrazilHosp Israelita Albert Einstein, São Paulo, BrazilUniv State São Paulo, Botucatu, SP, BrazilJundiai Sch Med, Jundiai, SP, BrazilUniv São Paulo, BR-14049 Ribeirao Preto, SP, BrazilSanta Casa Limeira, Limeira, SP, BrazilSanta Casa Sao Carlos, Sao Carlos, SP, BrazilMaternidade Leonor Mendes de Barros, São Paulo, BrazilUniversidade Federal de São Paulo, São Paulo, BrazilUniversidade Federal de São Paulo, São Paulo, BrazilCNPq: 402702/2008-5Web of Scienc

    Skin color and severe maternal outcomes: evidence from the brazilian network for surveillance of severe maternal morbidity

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    Taking into account the probable role that race/skin color may have for determining outcomes in maternal health, the objective of this study was to assess whether maternal race/skin color is a predictor of severe maternal morbidity. This is a secondary analysis of the Brazilian Network for Surveillance of Severe Maternal Morbidity, a national multicenter cross-sectional study of 27 Brazilian referral maternity hospitals. A prospective surveillance was performed to identify cases of maternal death (MD), maternal near miss (MNM) events, and potentially life-threatening conditions (PLTC), according to standard WHO definition and criteria. Among 9,555 women with severe maternal morbidity, data on race/skin color was available for 7,139 women, who were further divided into two groups: 4,108 nonwhite women (2,253 black and 1,855 from other races/skin color) and 3,031 white women. Indicators of severe maternal morbidity according to WHO definition are shown by skin color group. Adjusted Prevalence Ratios (PRadj - 95%CI) for Severe Maternal Outcome (SMO=MNM+MD) were estimated according to sociodemographic/obstetric characteristics, pregnancy outcomes, and perinatal results considering race. Results. Among 7,139 women with severe maternal morbidity evaluated, 90.5% were classified as PLTC, 8.5% as MNM, and 1.6% as MD. There was a significantly higher prevalence of MNM and MD among white women. MNMR (maternal near miss ratio) was 9.37 per thousand live births (LB). SMOR (severe maternal outcome ratio) was 11.08 per 1000 LB, and MMR (maternal mortality ratio) was 170.4 per 100,000 LB. Maternal mortality to maternal near miss ratio was 1 to 5.2, irrespective of maternal skin color. Hypertension, the main cause of maternal complications, affected mostly nonwhite women. Hemorrhage, the second more common cause of maternal complication, predominated among white women. Nonwhite skin color was associated with a reduced risk of SMO in multivariate analysis. Nonwhite skin color was associated with a lower risk for severe maternal outcomes. This result could be due to confounding factors linked to a high rate of Brazilian miscegenation.2019CNPQ - Conselho Nacional de Desenvolvimento Científico e Tecnológico402702/2008-
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