Publications by authors named "Alex M Machado"

is the primary vector of virus transmission that causes dengue, yellow fever, chikungunya and zika. The primary prevention method has been vector control and synthetic insecticides that can cause environmental side effects. Thus, the work aimed to evaluate the larvicidal potential of extracts and isolated compounds from against larvae.

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Pemphigus vulgaris (PV) and pemphigus foliaceus (PF) are blistering autoimmune diseases that depend on interaction between genetic and environmental factors. Viral infections, like herpes simplex viruses 1 and 2 (HSV1/2), cytomegalovirus (CMV), Epstein-Barr virus and dengue virus, could trigger or exacerbate pemphigus. IgM and IgG antibodies against these viruses in serum from PV and PF, their relatives and controls were determined.

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This study shows an experimental spillover infection of Sigmodontinae rodents with Rio Mamore hantavirus (RIOMV). Necromys lasiurus and Akodon sp were infected with 103 RNA copies of RIOMV by intraperitoneal administration. The viral genome was detected in heart, lung, and kidney tissues 18 days after infection (ai), and viral excretion in urine and faeces began at four and six ai, respectively.

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Improving the quality and performance of soybean oil as biodiesel depends on the chemical composition of its fatty acids and requires an increase in monounsaturated acids and a reduction in polyunsaturated acids. Despite its current use as a source of biofuel, soybean oil contains an average of 25 % oleic acid and 13 % palmitic acid, which negatively impacts its oxidative stability and freezing point, causing a high rate of nitrogen oxide emission. Gas chromatography and ion mobility mass spectrometry were conducted on soybean fatty acids from metabolically engineered seed extracts to determine the nature of the structural oleic and palmitic acids.

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Hantaviruses are members of the family Bunyaviridae and are an emerging cause of disease worldwide with high lethality in the Americas. In Brazil, the diagnosis for hantaviruses is based on immunologic techniques associated with conventional RT-PCR. A novel one-step SYBR Green real-time RT-PCR was developed for the detection and quantitation of Araraquara (ARAV) and Rio Mamore hantavirus (RIOMV).

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Hantavirus cardiopulmonary syndrome (HCPS) is an infectious disease caused by hantaviruses of the family Bunyaviridae, and is transmitted by aerosols of excreta of infected rodents. The aim of the present study was to determine antibody levels to hantavirus in the population that lives at frontier of Brazil and Argentina. Participated of the study 405 individuals living in the municipalities of Bandeirante, Santa Helena, Princesa and Tunapolis, state of Santa Catarina, Brazil.

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Background: Antigens for Hantavirus serological tests have been produced using DNA recombinant technology for more than twenty years. Several different strategies have been used for that purpose. All of them avoid the risks and difficulties involved in multiplying Hantavirus in the laboratory.

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Introduction: According to reports by the Ministry of Health, in the far western region of the State of Santa Catarina, there have been no reports of hantavirus pulmonary syndrome, a zoonotic disease transmitted by feces of infected rodents. A seroepidemiological study of residents of this region, was conducted, with the aim of determining the presence of hantavirus infections. A total of 340 volunteers of both genus, from the towns of Belmonte and Paraíso, were studied.

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Introduction: Hantavirus pulmonary and cardiovascular syndrome (HPCS) is an emerging serious disease in the Americas. Hantaviruses (Bunyaviridae) are the causative agents of this syndrome and are mainly transmitted through inhalation of aerosols containing the excreta of wild rodents. In the Ribeirão Preto region (state of São Paulo, Brazil), HPCS has been reported since 1998, caused by the Araraquara virus (ARAV), for which Necromys lasiurus is the rodent reservoir.

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Introduction: This paper show the standardization and use of the immunoenzymatic method using infected cells as antigens (EIA-ICC) for routine serological diagnosing of dengue.

Methods: In optimizing the test, a dose of 1,000 TCID50 of dengue type 3 virus (DENV-3) was used, and 100,000 C636 cells infected with 1,000 TCID50 (DENV-3) were used.

Results: The results obtained with EIA-ICC were compared with the HUMAN commercial dengue kit.

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Introduction: Arenavirus hemorrhagic fever is a severe emerging disease.

Methods: Considering that the levels of antibodies against arenavirus in the Brazilian population are completely unknown, we have standardized an ELISA test for detecting IgG antibodies using a recombinant nucleoprotein from the Junin virus as the antigen. This protein was obtained by inserting the gene of the Junin virus nucleoprotein into the genome of Autographa californica nucleopolyhedrovirus, using the Bac-to-Bac baculovirus expression system.

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Hantavirus pulmonary syndrome (HPS) is an increasing health problem in Brazil because of encroachment of sprawling urban, agricultural, and cattle-raising areas into habitats of subfamily Sigmodontinae rodents, which serve as hantavirus reservoirs. From 1993 through June 2007, a total of 884 cases of HPS were reported in Brazil (case-fatality rate 39%). To better understand this emerging disease, we collected 89 human serum samples and 68 rodent lung samples containing antibodies to hantavirus from a 2,500-km-wide area in Brazil.

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