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Emerging Plasmodium vivax resistance to chloroquine (CQ) may undermine malaria elimination efforts in South America. CQ-resistant P. vivax has been found in the major port city of Manaus but not in the main malaria hot spots across the Amazon Basin of Brazil, where CQ is routinely coadministered with primaquine (PQ) for radical cure of vivax malaria. Here we randomly assigned 204 uncomplicated vivax malaria patients from Juruá Valley, northwestern Brazil, to receive either sequential (arm 1) or concomitant (arm 2) CQ-PQ treatment. Because PQ may synergize the blood schizontocidal effect of CQ and mask low-level CQ resistance, we monitored CQ-only efficacy in arm 1 subjects, who had PQ administered only at the end of the 28-day follow-up. We found adequate clinical and parasitological responses in all subjects assigned to arm 2. However, 2.2% of arm 1 patients had microscopy-detected parasite recrudescences at day 28. When PCR-detected parasitemias at day 28 were considered, response rates decreased to 92.1% and 98.8% in arms 1 and 2, respectively. Therapeutic CQ levels were documented in 6 of 8 recurrences, consistent with true CQ resistance in vivo. In contrast, ex vivo assays provided no evidence of CQ resistance in 49 local P. vivax isolates analyzed. CQ-PQ coadministration was not found to potentiate the antirelapse efficacy of PQ over 180 days of surveillance; however, we suggest that larger studies are needed to examine whether and how CQ-PQ interactions, e.g., CQ-mediated inhibition of PQ metabolism, modulate radical cure efficacy in different P. vivax-infected populations. (This study has been registered at ClinicalTrials.gov under identifier NCT02691910.)

The "mosaic of autoimmunity" describes the multifactorial origin and diversity of expression of autoimmune diseases in humans. The term implies that different combinations of the many factors that are involved in auto-immunity produce varying and unique clinical pictures in a wide spectrum of autoimmune diseases. Most of the factors involved in autoimmunity can be categorized into four groups: genetic, immune defects, hormonal and environmental factors. In this communication, only the environmental factors are reviewed such as: infectious agents (represented by Epstein-Barr virus and cytomegalovirus), vaccines as triggers of autoimmunity, smoking and its relationship with rheumatoid arthritis, systemic lupus erythematosus, thyroid disease, multiple sclerosis and inflammatory bowel diseases. Some aspects of stress as implicated in causing autoimmunity and the processes leading to autoimmunity are reviewed as well.

Summary The progression of rheumatoid arthritis (RA) is quite variable, ranging from very mild or subclinical forms (approx. 10%) to rapidly progressing and debilitating forms (10‐15%). The majority of patients present with an intermediate stage with episodes of exacerbation separated by periods of relative inactivity, which evolves to progressive functional losses. To optimise the therapeutic management of early RA it is necessary to perform periodic evaluations of the clinical and laboratory test responses to the treatment instituted, as well as the parameters indicating disease prognosis. Composite measures are frequently used to evaluate the disease activity score (DAS), including the response criteria of the American College of Rheumatology (ACR), the response criteria and the DAS according to the European League Against Rheumatism (EULAR) and the composite indices of disease activity (CIDsA): DAS, the index of disease activity based on 28 joints (DAS 28), the simplified disease activity index (SDAI) and the clinical disease activity index (CDAI). The evaluation of prognosis includes investigation of the absence or occurrence of disease and joint damage remission. Due to the multifaceted nature of RA, no single clinical or laboratory parameter is able to describe satisfactorily the level of inflammatory activity or the disease prognosis at any given time.

Foi estudada a freqüência da cópula interespecífica entre espécimes de Biomphalaria glabrata e B. tenagophila. Os resultados da experiência levaram a conclusão de que há preferência pela cópula intraespecífica, ocorrendo, contudo, cópulas interespecíficas.

Two hundred and twenty tree children were studied regarding their response to the measles vaccine. The antibody response was measured by hemaglutination inhibition technique. Among the variables studied only the children's age at the time the vaccine was done had influence on the seroconvertion. Sex and nutritional status had no influence on the seroconvertion. A theoric model was designed to find at what age the vaccine had the best effect in preventing mortality. The age predicte was seven months. Foi estudada a indução de anticorpos anti-sarampo em 223 crianças nutridas e desnutridas vacinadas entre 6 e 24 meses e naquelas que permaneceram soronegativas com 1 dose da vacina realizada antes dos 12 meses que foram revacinadas após os 12 meses. A determinação de anticorpos anti-sarampo foi realizada pelas técnicas de inibição da hemaglutinação e de soroneutralização. Observamos que a taxa de soroconversão aumentou progressivamente com a idade, sendo de 43% aos 6 meses e de 80% aos 15 meses. A taxa de soroconversão em crianças marasmáticas foi semelhante à obtida em crianças nutridas, concordando com a literatura que vem demonstrando que crianças desnutridas não apresentam alteração na capacidade de resposta humoral à vacina. Utilizando os dados de mortalidade por sarampo e as taxas de soroconversão à vacina, idealizou-se um modelo hipotético para a avaliação da aplicação da vacina em diferentes idades e suas conseqüências em têrmos de mortalidade, e observou-se que quando a vacina é realizada em idades precoces (6-7 meses) o número de óbito esperado é inferior ao esperado quando a vacina é realizada em idades posteriores (9-11 meses), indicando que a proposta atual do Ministério da Saúde de aplicar dose única aos 9 meses, teoricamente aumentaria o risco de mortalidade. Considerando o número de crianças protegidas com 1 dose de vacina aplicada antes dos 12 meses e o número de crianças protegidas com a revacinação a taxa de soroconversão foi de 84,3%.