321 resultados para Cruz, Ireneo Fernando
Resumo:
We present the results of a paleoparasitologic, paleogenetic and paleobotanic analysis of coprolites recovered during the excavation of the church La Concepción in Santa Cruz de Tenerife. Coprolites (n = 4) were rehydrated and a multidisciplinary analysis was conducted. The paleobotanic analysis showed numerous silicates, seeds and fruits of the family Moraceae. In the paleoparasitologic study, Ascaris sp. eggs (n = 344) were identified. The paleogenetic results confirmed the Ascaris sp. infection as well as the European origin of human remains. These findings contribute to our knowledge of ancient helminthes infections and are the first paleoparasitological record of Ascaris sp. infection in Spain.
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Adult triatomines occasionally fly into artificially lit premises in Amazonia. This can result in Trypanosoma cruzi transmission to humans either by direct contact or via foodstuff contamination, but the frequency of such behaviour has not been quantified. To address this issue, a light-trap was set 45 m above ground in primary rainforest near Manaus, state of Amazonas, Brazil and operated monthly for three consecutive nights over the course of one year (432 trap-hours). The most commonly caught reduviids were triatomines, including 38 Panstrongylus geniculatus, nine Panstrongylus lignarius, three Panstrongylus rufotuberculatus, five Rhodnius robustus, two Rhodnius pictipes, one Rhodnius amazonicus and 17 Eratyrus mucronatus. Males were collected more frequently than females. The only month without any catches was May. Attraction of most of the known local T. cruzi vectors to artificial light sources is common and year-round in the Amazon rainforest, implying that they may often invade premises built near forest edges and thus become involved in disease transmission. Consequently, effective Chagas disease prevention in Amazonia will require integrating entomological surveillance with the currently used epidemiological surveillance.
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Rocky Mountain spotted fever (RMSF) is a tick-borne disease caused by the obligate intracellular bacterium Rickettsia rickettsii. Although RMSF was first reported in Colombia in 1937, it remains a neglected disease. Herein, we describe the investigation of a large cluster of cases of spotted fever rickettsiosis in a new area of Colombia.
Resumo:
Liver transplant seems to be an effective option to prolong survival in patients with end-stage liver disease, although it still can be followed by serious complications. Invasive fungal infections (ifi) are related to high rates of morbidity and mortality. The epidemiology of fungal infections in Brazilian liver transplant recipients is unknown. The aim of this observational and retrospective study was to determine the incidence and epidemiology of fungal infections in all patients who underwent liver transplantation at Albert Einstein Israeli Hospital between 2002-2007. A total of 596 liver transplants were performed in 540 patients. Overall, 77 fungal infections occurred in 68 (13%) patients. Among the 77 fungal infections, there were 40 IFI that occurred in 37 patients (7%). Candida and Aspergillus species were the most common etiologic agents. Candida species accounted for 82% of all fungal infections and for 67% of all IFI, while Aspergillus species accounted for 9% of all fungal infections and for 17% of all IFI. Non-albicans Candida species were the predominant Candida isolates. Invasive aspergillosis tended to occur earlier in the post-transplant period. These findings can contribute to improve antifungal prophylaxis and therapy practices in Brazilian centres.
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Leptospirosis is a zoonotic disease affecting most mammals and is distributed throughout the world. Several species of domestic and wild animals may act as reservoirs for this disease. The purpose of this study was to assess the exposure of free-ranging wild carnivores, horses and domestic dogs on a private reserve located in the northern Pantanal (Brazil) and the surrounding areas to Leptospira spp from 2002-2006, 75 free-ranging wild carnivores were captured in the Pantanal and serum samples were collected. In addition, samples from 103 domestic dogs and 23 horses in the region were collected. Serum samples were tested for the presence of Leptospira antibodies using the microscopic agglutination test. Thirty-two wild carnivores (42.7%) were considered positive with titres > 100, and 18 domestic dogs (17.5%) and 20 horses (74.1%) were also found to be positive. Our study showed that horses, dogs and several species of free-ranging wild carnivores have been exposed to Leptospira spp in the Pantanal, suggesting that the peculiar characteristics of this biome, such as high temperatures and an extended period of flooding, may favour bacterial persistence and transmission. In this region, wild carnivores and horses seem to be important hosts for the epidemiology of Leptospira species.
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Host use by vectors is important in understanding the transmission of zoonotic diseases, which can affect humans, wildlife and domestic animals. Here, a synthesis of host exploitation patterns by kissing-bugs, vectors of Chagas disease, is presented. For this synthesis, an extensive literature review restricted to feeding sources analysed by precipitin tests was conducted. Modern tools from community ecology and multivariate statistics were used to determine patterns of segregation in host use. Rather than innate preferences for host species, host use by kissing-bugs is influenced by the habitats they colonise. One of the major limitations of studies on kissing-bug foraging has been the exclusive focus on the dominant vector species. We propose that expanding foraging studies to consider the community of vectors will substantially increase the understanding of Chagas disease transmission ecology. Our results indicate that host accessibility is a major factor that shapes the blood-foraging patterns of kissing-bugs. Therefore, from an applied perspective, measures that are directed at disrupting the contact between humans and kissing-bugs, such as housing improvement, are among the most desirable strategies for Chagas disease control.
Resumo:
In this paper, we analysed the haemagglutinin (HA) gene identified by polymerase chain reaction from 90 influenza A H1N1 virus strains that circulated in Brazil from April 2009-June 2010. A World Health Organization sequencing protocol allowed us to identify amino acid mutations in the HA protein at positions S220T (71%), D239G/N/S (20%), Y247H (4.5%), E252K (3.3%), M274V (2.2%), Q310H (26.7%) and E391K (12%). A fatal outcome was associated with the D239G mutation (p < 0.0001). Brazilian HA genetic diversity, in comparison to a reference strain from California, highlights the role of influenza virus surveillance for study of viral evolution, in addition to monitoring the spread of the virus worldwide.
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Throughout Brazil, Cryptococcus neoformans is the cause of cryptococcosis, whereas Cryptococcus gattii is endemic to the northern and northeastern states. In this study, the molecular types of 63 cryptococcal isolates recovered from the cerebrospinal fluid of meningitis patients diagnosed between 2008-2010 in Teresina, Piauí, Brazil, were analysed. Out of the 63 patients, 37 (58.7%) were human immunodeficiency virus (HIV)-positive and 26 (41.3%) were HIV-negative. URA5-restriction fragment length polymorphism analysis identified 37/63 (58.7%) isolates as the C. neoformans VNI genotype, predominantly in HIV-positive patients (32/37, 86.5%), and 24/63 (38.1%) as the C. gattii VGII genotype, mostly in HIV-negative patients (21/26, 80.8%). The occurrence of C. gattii VGII in six apparently healthy children and in seven adolescents/young adults in this region reaffirms the endemic occurrence of C. gattii VGII-induced primary cryptococcosis and early cryptococcal infection. Lethality occurred in 18/37 (48.6%) of the HIV-positive subjects and in 13/26 (50%) of the HIV-negative patients. Our results provide new information on the molecular epidemiology of C. neoformans and C. gattii in Brazilian endemic areas.
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Leishmania infantum (syn. Leishmania chagasi) is the etiological agent of visceral leishmaniasis (VL) in Brazil. The epidemiology of VL is poorly understood. Therefore, a more detailed molecular characterization at an intraspecific level is certainly needed. Herein, three independent molecular methods, multilocus microsatellite typing (MLMT), random amplification of polymorphic DNA (RAPD) and simple sequence repeats-polymerase chain reaction (SSR-PCR), were used to evaluate the genetic diversity of 53 L. infantum isolates from five different endemic areas in Brazil. Population structures were inferred by distance-based and Bayesian-based approaches. Eighteen very similar genotypes were detected by MLMT, most of them differed in only one locus and no correlation was found between MLMT profiles, geographical origin or the estimated population structure. However, complex profiles composed of 182 bands obtained by both RAPD and SSR-PCR assays gave different results. Unweighted pair group method with arithmetic mean trees built from these data revealed a high degree of homogeneity within isolates of L. infantum. Interestingly, despite this genetic homogeneity, most of the isolates clustered according to their geographical origin.
Resumo:
While human immunodeficiency virus (HIV)-1 chemokine co-receptors 5 tropism and the GWGR motif in the envelope third variable region (V3 loop) have been associated with a slower disease progression, their influence on antiretroviral response remains unclear. The impact of baseline V3 characteristics on treatment response was evaluated in a randomised, double blind, prospective cohort study with patients initiating highly active antiretroviral therapy with lopinavir or efavirenz plus azithothymidine/3TC (1:1) over 48 weeks. Similar virological and immunological responses were observed for both treatment regimens. The 43 individuals had a mean baseline CD4 T cell count of 119 cells/mm³ [standard deviation (SD) = 99] and a mean viral load of 5.09 log10 copies/mL (SD = 0.49). The GWGR motif was not associated with a CD4 T cell response, but predicted R5 tropism by the geno2pheno[clinical20%] algorithm correlated with higher CD4 T cell levels at all monitoring points (p < 0.05). Moreover, higher false-positive rates (FPR) values from this analysis revealed a strong correlation with CD4 T cell recovery (p < 0.0001). Transmitted drug resistance mutations, documented in 3/41 (7.3%) cases, were unrelated to the assigned antiretroviral regimen and had no impact on patient outcomes. In conclusion, naÏve HIV-1 R5 infected patients exhibited higher CD4 T cell counts at baseline; this difference was sustained throughout therapy. The geno2pheno[clinical] option FPR positively correlated with CD4 T cell gain and may be useful in predicting CD4 T cell recovery.
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We present results of the paleoparasitological analysis of Cervidae coprolites that were recovered from the archaeological site Furna do Estrago, Pernambuco, Brazil. Trichuris sp. eggs were recovered from the coprolite samples dated 1,040 ± 50 years before present. This is the first record of Trichuris sp. in semiarid Cervidae, unexpectedly recorded in archaeological material.
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We present the results of paleoparasitological analyses in coprolites of Kerodon rupestris, rodent endemic to rocky areas of Brazil's semiarid region. The coprolites were collected from excavations at the archaeological site of Toca dos Coqueiros, in the National Park of Serra da Capivara, southeastern of state of Piauí. Syphacia sp. (Nematoda: Oxyuridae) eggs were identified in coprolites dated at 5,300 ± 50 years before present. This is the first record of the genus Syphacia in rodent coprolites in the Americas.
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Rocio virus (ROCV) is an encephalitic flavivirus endemic to Brazil. Experimental flavivirus infections have previously demonstrated a persistent infection and, in this study, we investigated the persistence of ROCV infection in golden hamsters (Mesocricetus auratus). The hamsters were infected intraperitoneally with 9.8 LD50/0.02 mL of ROCV and later anaesthetised and sacrificed at various time points over a 120-day period to collect of blood, urine and organ samples. The viral titres were quantified by real-time-polymerase chain reaction (qRT-PCR). The specimens were used to infect Vero cells and ROCV antigens in the cells were detected by immunefluorescence assay. The levels of antibodies were determined by the haemagglutination inhibition technique. A histopathological examination was performed on the tissues by staining with haematoxylin-eosin and detecting viral antigens by immunohistochemistry (IHC). ROCV induced a strong immune response and was pathogenic in hamsters through neuroinvasion. ROCV was recovered from Vero cells exposed to samples from the viscera, brain, blood, serum and urine and was detected by qRT-PCR in the brain, liver and blood for three months after infection. ROCV induced histopathological changes and the expression of viral antigens, which were detected by IHC in the liver, kidney, lung and brain up to four months after infection. These findings show that ROCV is pathogenic to golden hamsters and has the capacity to cause persistent infection in animals after intraperitoneal infection.
Resumo:
Outbreaks caused by vaccine-derived polioviruses are challenging the final eradication of paralytic poliomyelitis. Therefore, the surveillance of the acute flaccid paralysis cases based on poliovirus isolation and characterization remains an essential activity. Due to the use of trivalent oral poliovirus vaccine (OPV), mixtures containing more than one serotype of Sabin-related polioviruses are frequently isolated from clinical samples. Because each poliovirus isolate needs to be individually analyzed, we designed polymerase chain reaction primers that can selectively distinguish and amplify a genomic segment of the three Sabin-related poliovirus serotypes present in mixtures, thus, optimizing the diagnosis and providing prompt information to support epidemiologic actions.
Resumo:
Dengue fever is the most important arbovirus infection found in tropical regions around the world. Dispersal of the vector and an increase in migratory flow between countries have led to large epidemics and severe clinical outcomes, such as dengue haemorrhagic fever and dengue shock syndrome. This study analysed the genetic variability of the dengue virus serotype 1 (DENV-1) in Brazil with regard to the full-length structural genes C/prM/M/E among 34 strains isolated during epidemics that occurred in the country between 1994-2011. Virus phylogeny and time of divergence were also evaluated with only the E gene of the strains isolated from 1994-2008. An analysis of amino acid differences between these strains and the French Guiana strain (FGA/89) revealed the presence of important nonsynonymous substitutions in the amino acid sequences, including residues E297 (Met→Thr) and E338 (Ser→Leu). A phylogenetic analysis of E proteins comparing the studied isolates and other strains selected from the GenBank database showed that the Brazilian DENV-1 strains since 1982 belonged to genotype V. This analysis also showed that different introductions of strains from the 1990s represented lineage replacement, with the identification of three lineages that cluster all isolates from the Americas. An analysis of the divergence time of DENV-1 indicated that the lineage circulating in Brazil emerged from an ancestral lineage that originated approximately 44.35 years ago.