Concurrent Outbreak of Norovirus Genotype I and Enterotoxigenic Escherichia coli on a U.S. Navy Ship following a Visit to Lima, Peru

An outbreak of norovirus (NoV) genotype I and Enterotoxigenic Escherichia coli (ETEC) occurred among US Navy Ship personnel following a visit to Lima, Peru, in June 2008. Visiting a specific area in Lima was significantly associated with illness. While ETEC and NoV are commonly recognized as causative agents of outbreaks, co-circulation of both pathogens has been rarely observed in shipboard outbreaks

Variant antigen diversity in Trypanosoma vivax is not driven by recombination.

African trypanosomes (Trypanosoma) are vector-borne haemoparasites that survive in the vertebrate bloodstream through antigenic variation of their Variant Surface Glycoprotein (VSG). Recombination, or rather segmented gene conversion, is fundamental in Trypanosoma brucei for both VSG gene switching and for generating antigenic diversity during infections. Trypanosoma vivax is a related, livestock pathogen whose VSG lack structures that facilitate gene conversion in T. brucei and mechanisms underlying its antigenic diversity are poorly understood. Here we show that species-wide VSG repertoire is broadly conserved across diverse T. vivax clinical strains and has limited antigenic repertoire. We use variant antigen profiling, coalescent approaches and experimental infections to show that recombination plays little role in diversifying T. vivax VSG sequences. These results have immediate consequences for both the current mechanistic model of antigenic variation in African trypanosomes and species differences in virulence and transmission, requiring reconsideration of the wider epidemiology of animal African trypanosomiasis

Whole brain radiotherapy for brain metastases from breast cancer: estimation of survival using two stratification systems

BACKGROUND: Brain metastases (BM) are the most common form of intracranial cancer. The incidence of BM seems to have increased over the past decade. Recursive partitioning analysis (RPA) of data from three Radiation Therapy Oncology Group (RTOG) trials (1200 patients) has allowed three prognostic groups to be identified. More recently a simplified stratification system that uses the evaluation of three main prognostics factors for radiosurgery in BM was developed. METHODS: To analyze the overall survival rate (OS), prognostic factors affecting outcomes and to estimate the potential improvement in OS for patients with BM from breast cancer, stratified by RPA class and brain metastases score (BS-BM). From January 1996 to December 2004, 174 medical records of patients with diagnosis of BM from breast cancer, who received WBRT were analyzed. The surgery followed by WBRT was used in 15.5% of patients and 84.5% of others patients were submitted at WBRT alone; 108 patients (62.1%) received the fractionation schedule of 30 Gy in 10 fractions. Solitary BM was present in 37.9 % of patients. The prognostic factors evaluated for OS were: age, Karnofsky Performance Status (KPS), number of lesions, localization of lesions, neurosurgery, chemotherapy, absence extracranial disease, RPA class, BS-BM and radiation doses and fractionation. RESULTS: The OS in 1, 2 and 3 years was 33.4 %, 16.7%, and 8.8 %, respectively. The RPA class analysis showed strong relation with OS (p < 0.0001). The median survival time by RPA class in months was: class I 11.7, class II 6.2 and class III 3.0. The significant prognostic factors associated with better OS were: higher KPS (p < 0.0001), neurosurgery (P < 0.0001), single metastases (p = 0.003), BS-BM (p < 0.0001), control primary tumor (p = 0.002) and absence of extracranial metastases (p = 0.001). In multivariate analysis, the factors associated positively with OS were: neurosurgery (p < 0.0001), absence of extracranial metastases (p <0.0001) and RPA class I (p < 0.0001). CONCLUSION: Our data suggests that patients with BM from breast cancer classified as RPA class I may be effectively treated with local resection followed by WBRT, mainly in those patients with single BM, higher KPS and cranial extra disease controlled. RPA class was shown to be the most reliable indicators of survival

Duffy Negative Antigen Is No Longer a Barrier to Plasmodium vivax – Molecular Evidences from the African West Coast (Angola and Equatorial Guinea)

Recent reports of Plasmodium vivax infections, the most widely distributed species of human malaria, show that this parasite is evolving and adapting, becoming not only more aggressive but also more frequent in countries where it was not present in the past, becoming, therefore, a major source of concern. Thus, it is extremely important to perform new studies of its distribution in West and Central Africa, where there are few reports of its presence, due to the high prevalence of Duffy-negative individuals. The aim of this study was to investigate the presence of P. vivax in Angola and in Equatorial Guinea, using blood samples and mosquitoes. The results showed that P. vivax seems to be able to invade erythrocytes using receptors other than Duffy, and this new capacity is not exclusive to one strain of P. vivax, since we have found samples infected with two different strains: VK247 and classic. Additionally we demonstrated that the parasite has a greater distribution than previously thought, calling for a reevaluation of its worldwide distribution

Genetic diversity of Leishmania amazonensis strains isolated in northeastern Brazil as revealed by DNA sequencing, PCR-based analyses and molecular karyotyping

Abstract\ud \ud \ud \ud Background\ud \ud Leishmania (Leishmania) amazonensis infection in man results in a clinical spectrum of disease manifestations ranging from cutaneous to mucosal or visceral involvement. In the present study, we have investigated the genetic variability of 18 L. amazonensis strains isolated in northeastern Brazil from patients with different clinical manifestations of leishmaniasis. Parasite DNA was analyzed by sequencing of the ITS flanking the 5.8 S subunit of the ribosomal RNA genes, by RAPD and SSR-PCR and by PFGE followed by hybridization with gene-specific probes.\ud \ud \ud \ud Results\ud \ud ITS sequencing and PCR-based methods revealed genetic heterogeneity among the L. amazonensis isolates examined and molecular karyotyping also showed variation in the chromosome size of different isolates. Unrooted genetic trees separated strains into different groups.\ud \ud \ud \ud Conclusion\ud \ud These results indicate that L. amazonensis strains isolated from leishmaniasis patients from northeastern Brazil are genetically diverse, however, no correlation between genetic polymorphism and phenotype were found.We thank Lucile FloeterWinter for critical reading of the manuscript and Artur T.L. de Queiroz for initial help with phylogenetic analysis. This work is supported by grants from CNPq, FAPESB and PAPES/FIOCRUZ. J.P.C. de Oliveira was supported by a CNPq fellowship; C.I.O. and F.M.C.F were supported by a FAPESB fellowship. AAC, AB, and CIO are senior investigators from CNPq. AB is a senior investigator for Instituto de Investigação em Imunologia (iii).We thank Lucile Floeter-Winter for critical reading of the manuscript and Artur T.L. de Queiroz for initial help with phylogenetic analysis. This work is supported by grants from CNPq, FAPESB and PAPES/FIOCRUZ. J.P.C. de Oliveira was supported by a CNPq fellowship; C.I.O. and F.M.C.F were supported by a FAPESB fellowship. AAC, AB, and CIO are senior investigators from CNPq. AB is a senior investigator for Instituto de Investigação em Imunologia (iii)