A global reference for caesarean section rates (C-Model): a multicountry cross-sectional study

Objective: To generate a global reference for caesarean section (CS) rates at health facilities. Design: Cross-sectional study. Setting: Health facilities from 43 countries. Population/sample: Thirty eight thousand three hundred and twenty-four women giving birth from 22 countries for model building and 10,045,875 women giving birth from 43 countries for model testing. Methods: We hypothesised that mathematical models could determine the relationship between clinical-obstetric characteristics and CS. These models generated probabilities of CS that could be compared with the observed CS rates. We devised a three-step approach to generate the global benchmark of CS rates at health facilities: creation of a multi-country reference population, building mathematical models, and testing these models. Main outcome measures: Area under the ROC curves, diagnostic odds ratio, expected CS rate, observed CS rate. Results: According to the different versions of the model, areas under the ROC curves suggested a good discriminatory capacity of C-Model, with summary estimates ranging from 0.832 to 0.844. The C-Model was able to generate expected CS rates adjusted for the case-mix of the obstetric population. We have also prepared an e-calculator to facilitate use of C-Model (www.who.int/reproductivehealth/publications/maternal_perinatal_health/c-model/en/). Conclusions: This article describes the development of a global reference for CS rates. Based on maternal characteristics, this tool was able to generate an individualised expected CS rate for health facilities or groups of health facilities. With C-Model, obstetric teams, health system managers, health facilities, health insurance companies, and governments can produce a customised reference CS rate for assessing use (and overuse) of CS. (AU)

Avaliação da genotoxicidade da Ilex paraguariensis (erva mate) pelo teste do micronúcleo / Evaluation of the genotoxicity of Ilex paraguariensis (yerba mate) by micronucleus test

A Ilex paraguariensis é espécie nativa da América do Sul. O consumo de erva mate tem sido associado ao aumento nas taxas de câncer oral, de orofaringe, esôfago e laringe. O objetivo deste estudo foi investigar o potencial genotóxico da exposição a dose única de Ilex paraguariensis através do teste do micronúcleo. Para este estudo, foram utilizados 32 ratos Wistar albinos machos e adultos, divididos em 4 grupos: A - Composto por 8 ratos que receberam infusão de chá preparado na concentração de 5% de erva mate (concentração usualmente encontrada no chá de consumo humano); B - Composto por 8 ratos que receberam chá preparado por imersão em água fria na concentração de 5% de erva mate; C - Composto por 8 ratos, os quais receberam ciclofosfamida em dose única subcutânea (50mg/kg) no primeiro dia do experimento (grupo controle positivo); D - Composto por 8 ratos, os quais receberam somente água (grupo controle negativo). Todos os animais receberam ração ad libitum. Os animais dos grupos A, B e D foram submetidos à eutanásia 48 horas após o início do experimento e os do grupo C, 24 horas após. Foi coletado material da medula óssea de cada rato após a eutanásia para realização do teste do micronúcleo em eritrócito policromático, para avaliação do grau de genotoxicidade. A mediana de micronúcleos para o grupo A (chá mate preparado com infusão) foi de 0,00, do grupo B (chá mate em imersão em água fria) foi de 0,00, do grupo C (ciclofosfamida - controle positivo) foi de 9,00, e no grupo D (controle negativo) foi de 0,00. Não se observou genotoxicidade da Ilex paraguariensis, em ambas as formas de preparo do chá, através do teste de micronúcleo, ao nível de significância de 5%.

The Ilex paraguariensis is a native species of South America. Yerba mate consumption has been associated with increased rates of oral, oropharynx, esophagus and larynx cancer. The aim of this study was to investigate the genotoxic potential of the exposure to a single dose of Ilex paraguariensis by the micronucleus test. For this study, 32 male, adult Wistar rats were used, divided into 4 groups: A - Consisting of 8 rats, which received an infusion of tea prepared at a concentration of 5% of mate (concentration usually found in human consumption of tea); B - Consisting of 8 rats, which received tea prepared immersed in cold water at a concentration of 5% of mate; C - Consisting of 8 rats, which received a single subcutaneous dose of cyclophosphamide (50mg/kg) on the first day of the experiment (positive control group); D - Consisting of 8 rats, which received only water (negative control group). All animals received food ad libitum. The animals in groups A, B and D were sacrificed 48 hours after the beginning of the experiment and group C, 24 hours after. Material from the bone marrow of each rat was collected after euthanasia to perform the micronucleus test in polychromatic erythrocyte to assess the degree of genotoxicity. The median of micronuclei for group A (mate tea prepared with infusion) was 0.00, for group B (mate tea immersed in cold water) was 0.00, for group C (cyclophosphamide - positive control) was 9.00 and for group D (negative control) was 0.00. No genotoxicity of Ilex paraguariensis was observed in both tea preparation methods by the micronucleus test at a significance level of 5%.

Baccharis rufescens Spreng. var. tenuifolia (DC. ) Baker: contribuição ao estudo farmacognóstico / Baccharis rufescens Spreng. var. tenuifolia (DC. ) Baker: contribution to the pharmacognostic study

Baccharis rufescens Spreng. var. tenuifolia (DC.) Baker pertence à família Asteraceae e é usada na medicina tradicional como estomáquico e hepatoprotetor. Um estudo fitoquímico mostrou a presença de flavonoides e triterpenos, sendo que os extratos clorofórmico e metanólico de folhas apresentaram-se ativos no bioensaio de toxicidade sobre Artemia salina Leach. Além disso, extratos clorofórmicos evidenciaram a presença de peróxidos, sugerindo sua aplicação no tratamento da malária (Schenkel at al., 2002; Montanher et al., 2002; Moreira et al., 2003). Considerando a importância farmacológica de B. rufescens var. tenuifolia, o presente trabalho objetivou o estudo morfoanatômico e histoquímico do caule e da folha dessa espécie, a fim de fornecer subsídios farmacognósticos para o controle de qualidade. O material botânico foi submetido às técnicas usuais empregadas na microscopia de luz e microscopia eletrônica de varredura. Folha anfiestomática, presença de estômatos anomocíticos, tricomas glandulares capitados bisseriados, tricomas tectores flageliformes simples unisseriados, dutos secretores associados ao floema, calota de fibras perivasculares e cristais de oxalato de cálcio do tipo estiloide e prismático na região medular do caule foram as principais características observadas que auxiliam na identificação do táxon.

Baccharis rufescens Spreng. var. tenuifolia (DC.) Baker belongs to the Asteraceae family. It is used for liver and stomach problems in traditional medicine. Previous phytochemical data reported flavonoid and triterpene contents. Chloroform and methanol extracts of the leaves showed activity in the bioassay of brine shrimp. Chloroform extracts showed the presence of peroxides that can be used to treat malaria (Schenkel et al., 2002; Montanher et al., 2002; Moreira et al., 2003). Considering the pharmacological importance of B. rufescens var. tenuifolia, the purpose of this paper was to perform the anatomical analysis of aerial vegetative parts of Baccharis rufescens var. tenuifolia in order to provide pharmacognostic data for quality control. The plant material was studied by the usual methods of light and scanning electron microscopy. Amphistomatic leaves, anomocytic stomata, biseriate capitate glandular trichomes, uniseriate simple flagelliform non-glandular trichomes, secretory ducts associated to the phloem, perivascular fiber cap, calcium oxalate as prismatic and styloid crystals in the pith of the stem were reported as the mainly anatomical data for B. rufescens var. tenuifolia.Ouvir Ler foneticamente.