Mitermayer Galvão dos Reis

A C677T methylenetetrahydrofolate reductase (MTHFR) polymorphism and G20210A mutation in the prothrombin gene of sickle cell anemia patients from Northeast Brazil.

The C677T methylenetetrahydrofolate reductase (MTHFR) gene polymorphism and the G20210A mutation at the 3′ untranslated region (3′UTR) of the prothrombin gene may be considered to be genetic risk factors that contribute to the clinical heterogeneity in sickle cell disease. The current study investigated a group of sickle cell (SS) patients from Salvador‐Bahia, Northeast Brazil in order to determine the prevalence of these polymorphisms, using the polymerase chain reaction (PCR) and restriction fragment length polymorphim (RFLP) techniques. Out of 69 SS patients diagnosed with the C677T MTHFR gene polymorphism, 13 (18.6%) were heterozygous and four (5.7%) homozygous. The G20210A mutation was not found in 50 SS patients investigated. These results became important once the C677T MTHFR gene polymorphism was found to be an independent risk factor for vascular disease, a common clinical event in sickle cell disease.

Epizootic Outbreak of Yellow Fever Virus and Risk for Human Disease in Salvador, Brazil.

Background: Yellow fever virus (YFV) is an RNA virus maintained in an enzootic, sylvatic cycle involving nonhuman primates (NHPs) and sylvatic mosquito vectors primarily of the genus Haemagogus and Sabethes. Transmission occasionally spills over to humans entering forested regions. In the Americas, urban transmission of YFV to humans has not occurred since the mid-1900s because of vaccination and near-elimination of the anthropophilic Aedes aegypti, the urban vector (1). However, concerns about reemergence of urban YFV have recently increased because of the reappearance and rapid spread of A aegypti in the urban environment. Furthermore, immunization coverage for YFV is insufficient because vaccination is generally indicated only for higher-risk populations, such as those living in or travelling to areas with sylvatic transmission. Objective: To investigate the 2017 epizootic outbreak of YFV and the risk for human disease in Salvador, Brazil. Methods and Findings: Since November 2016, deaths of NHPs due to YFV in Brazil have been reported in the state of So Paulo. Beginning in December 2016, human cases were also reported in the states of So Paulo and Minas Gerais. By the end of May 2017, the YFV outbreak in humans had spread to 9 Brazilian states, with more than 130 municipalities reporting confirmed cases (Appendix Figure 1), all deemed of sylvatic origin (rather than via urban A aegypti transmission). Of 3240 suspected reported human cases, 792 were laboratory-confirmed. Among all reported patients, 435 died and 274 of these had laboratory-confirmed infection with YFV (casefatality ratio for laboratory-confirmed cases, 34.6%) (2). Appendix Figure 1. Brazilian states where human cases of YFV were reported between December 2016 and May 2017, according to laboratory confirmation status. YFV = yellow fever virus. Reports of deaths of NHPs due to YFV also simultaneously increased. By the end of May 2017, a total of 3850 NHPs was suspected to have died of YFV infection, 642 of which were confirmed from 12 states (2). Since the beginning of the outbreak, the Brazilian Ministry of Health has distributed more than 25 million YFV vaccine doses to persons in areas with confirmed human or NHP cases, likely reducing incidence (2). On 14 January 2017, deaths of NHPs suspected of having YFV were first reported in Salvador, the fourth largest Brazilian city, which had not been considered a risk area for transmission (Appendix Figure 1). The number of NHPs found dead throughout the city rapidly increased, and by 24 August, 205 NHPs of the genus Callithrix suspected of having infection with YFV had been collected (Appendix Figure 2). Reverse transcriptase polymerase chain reaction testing for the virus was done on tissue samples of 21 dead animals at the Oswaldo Cruz Foundation in Rio de Janeiro; samples from 13 animals (61.9%) tested positive. Animals suspected of being infected were found throughout Salvador, with a cluster (3 of the 13 YFV-positive animals) around a city park, a 0.66-km2 recreational area of residual Atlantic forest with trees less than 10 m high (Figure). Appendix Figure 2. Temporal distribution of NHPs collected in Salvador, Brazil, by epidemiologic week in 2017. NHP = nonhuman primate. Figure. Spatial distribution of locations of NHP collections according to YFV status and of sites of mosquito collections in Salvador, Brazil. Distribution of 7 of the 8 YFV-negative NHPs, all 13 of the YFV-positive NHPs, and 173 of the 184 NHPs that were not tested is shown. NHP = nonhuman primate; YFV = yellow fever virus. To investigate potential vectors involved in YFV transmission among NHPs in Salvador, we initiated ground-level mosquito collections within and around the city park and the naval base, another preserved Atlantic forest area where dead, YFV-positive NHPs were found. During 10 days of fieldwork in 26 sites between 10 April and 7 June 2017, a total of 435 adult mosquitoes (307 females) was captured using human landing catches (Table). Most females captured were Wyeomyia species and A albopictus. Although we did not capture Haemagogus or Sabethes species, Haemagogus mosquitoes were identified in Salvador in January 2017 in a suburban, forested area. Pools of captured female mosquitoes from each species were tested for YFV by reverse transcriptase polymerase chain reaction (primers CAG and YF7) (3) and cell culture (C6/36, A albopictus), and none was positive. Table. Number of Mosquitos Collected at Ground Level in Salvador, Brazil* Discussion: To date, urban Aedes mosquitoes have not been associated with YFV transmission to humans in Brazil. However, cases of YFV in NHPs in densely urbanized areas pose a considerable risk for resurgence of A aegyptimediated YFV transmission to humans. Salvador has long been an epicenter of dengue transmission and more recently of Zika (4) and chikungunya (5) viruses, all with A aegypti as the main vector. In addition, A albopictus, which is susceptible to YFV infection in laboratory settings, is commonly found here, particularly in peridomestic and green areas. Although never implicated in natural YFV transmission, this species was only introduced into the Americas in the 1980s. Continuous entomologic and veterinary surveillance of mosquitoes and NHP deaths, accompanied by laboratory testing for YFV, is the cornerstone of assessing the risk that this virus will establish an urban transmission cycle. In parallel, scaling up YFV vaccination coverage is critical to prevent additional human cases of this disease.

Elevated VEGFA mRNA levels in oral squamous cell carcinomas and tumor margins: a preliminary study

BACKGROUND New blood vessel formation events are essential for tumor clonal expansion and progression. Despite the importance of vascular endothelial growth factor A (VEGFA) for tumor angiogenesis, few studies have evaluated the expression profile of this gene in oral squamous cell carcinoma (OSCC) and tumor margins (TM). This study aimed to evaluate the expression of the VEGFA gene and its protein in OSCC and TM. METHODS Gene expression was evaluated in cryopreserved samples of OSCCs (n = 44), TM (n = 7), and normal mucosa from healthy patients (n = 3; NM). Quantitative PCRs were performed using the TaqMan system for the VEGFA gene, and gene expression was determined using the 2(-∆∆CQ) method. For immunohistochemical evaluation, 27 OSCC samples were embedded in a tissue microarray (TMA) block and reactions were performed using the Advance system. RESULTS VEGFA transcript levels were 1.7-fold higher in OSCC than in NM samples. VEGFA mRNA was overexpressed in TM samples compared to NM (3.4-fold) and OSCC (2.0-fold) samples. VEGFA transcript level was overexpressed in T3-T4 tumors, metastatic lymph nodes, and stage III-IV OSCCs. Immunoreactivity of the VEGFA protein was detected in the cytoplasm of parenchymal and stromal cells, mainly in endothelial cells and fibroblasts. CONCLUSION Our results show that VEGFA was overexpressed in aggressive OSCCs and that VEGFA expression may be an important prognostic factor in this type of cancer. Finally, tumor margins may be involved in the production of angiogenic molecules.

Limited evidence of HCV transmission in stable heterosexual couples from Bahia, Brazil

HCV infected patients frequently ask their physician about the risk of transmission to their partners. Although it is easy to answer that the risk does exist, it is difficult to quantify. We studied the transmission of HCV infection in stable heterosexual couples: anti-HCV positive patients in hemodialytic therapy and their partners. Thirty-four couples were tested by third generation ELISA and RIBA. Blood samples of anti-HCV positive patients were evaluated by RT-PCR and detected sequences were genotyped by restriction fragment length polymorphism. Concordance of infection was observed in only one couple in which both subjects were in dialytic therapy. One other partner had two positive ELISA tests and an indeterminate RIBA, with negative RT-PCR, which may suggest a false positive or a previous resolved infection. Either sexual relations, sharing of personal items and history of parenteral exposure (hemodialysis, blood transfusion) could explain transmission in the only couple with concordant infection. We observed, in accordance with previous reports, that this risk is minimal or negligible in stable heterosexual couples.