93 research outputs found
Development of a semi-quantitative pcr method using a plasmid cloned with part of the gb gene of cytomegalovirus
A infecção por citomegalovírus é disseminada em nosso meio e costuma acometer, com significante morbimortalidade, indivíduos imunodeprimidos, especialmente, transplantados de medula óssea e de rim bem como pacientes com AIDS. Neste trabalho, descrevemos o desenvolvimento de uma PCR semiquantitativa para detectar e quantificar cargas de CMV, presentes em materiais clínicos. Para tanto, inserimos em plasmídios PCR II (Invitrogen, USA), o fragmento com 296 pares-base do gene da glicoproteína B do CMV. Os plasmídios com inserto foram transfectados em Escherichia coli, multiplicados, verificados quanto à presença do inserto por seqüenciamento nucleotídico, purificados, e quantificados. Os plasmídios com inserto foram titulados em diluições decimais e as mesmas foram submetidas à PCR descrita anteriormente,que foi, também, utilizada nos testes semiquantitativos, permitindo determinar a sensibilidade da técnica, 867 cópias de CMV / mg de DNA. Com base nas densidades das bandas eletroforéticas dos amplicons de amostras clínicas, comparadas às da titulação de plasmídios contendo inserto de glicoproteína B do CMV, obtivemos as cargas virais. A técnica de PCR semiquantitativa, por nós padronizada, tem, como vantagens, o baixo custo e o fácil manuseio após sua padronização, podendo ser testada na detecção da carga de CMV em diferentes tipos de pacientes com suspeita de citomegalovirose.Cytomegalovirus (CMV) infections are highly prevalent in Brazil. CMV is a caus ative of significant morbidity and mortality in immunodepressed patients including bone marrow and kidney transplanted individuals as well as AIDS patients. The present work shows on the development of a semi-quantitative PCR for determination of CMV load in clinical samples. A 296 nucleotides segment of the gB gene of CMV was inserted into PCR II plasmids (Invitrogen, USA), and these plasmids were transfected into Escherichia coli. After confirmation of the presence of the insert and multiplication, the plasmids were quantified in the original sample. Following, a titration of the cloned plasmids was carried out in order to determinate the sensitivity of the semiquantitative PCR using primers that anneal to the gB gene of CMV. That was 867 plasmid copies/mg of DNA. The CMV load in the leukocytes of clinical samples was determined after PCR, by comparison of densities of the amplicon bands with those of the quantified cloned plasmid titration. This is a is a simple and low cost CMV semi-quantitative PCR, and it could be used for detecting viral loads in clinical samples of patients infected with CMV.
 
Genetic diversity of the E Protein of Dengue Type 3 Virus
<p>Abstract</p> <p>Background</p> <p>Dengue is the most important arbovirus disease in tropical and subtropical countries. The viral envelope (E) protein is responsible for cell receptor binding and is the main target of neutralizing antibodies. The aim of this study was to analyze the diversity of the E protein gene of DENV-3. E protein gene sequences of 20 new viruses isolated in Ribeirao Preto, Brazil, and 427 sequences retrieved from GenBank were aligned for diversity and phylogenetic analysis.</p> <p>Results</p> <p>Comparison of the E protein gene sequences revealed the presence of 47 variable sites distributed in the protein; most of those amino acids changes are located on the viral surface. The phylogenetic analysis showed the distribution of DENV-3 in four genotypes. Genotypes I, II and III revealed internal groups that we have called lineages and sub-lineages. All amino acids that characterize a group (genotype, lineage, or sub-lineage) are located in the 47 variable sites of the E protein.</p> <p>Conclusion</p> <p>Our results provide information about the most frequent amino acid changes and diversity of the E protein of DENV-3.</p
Recommended from our members
Hematopoietic Cell Transplantation in Patients With Primary Immune Regulatory Disorders (PIRD): A Primary Immune Deficiency Treatment Consortium (PIDTC) Survey.
Primary Immune Regulatory Disorders (PIRD) are an expanding group of diseases caused by gene defects in several different immune pathways, such as regulatory T cell function. Patients with PIRD develop clinical manifestations associated with diminished and exaggerated immune responses. Management of these patients is complicated; oftentimes immunosuppressive therapies are insufficient, and patients may require hematopoietic cell transplant (HCT) for treatment. Analysis of HCT data in PIRD patients have previously focused on a single gene defect. This study surveyed transplanted patients with a phenotypic clinical picture consistent with PIRD treated in 33 Primary Immune Deficiency Treatment Consortium centers and European centers. Our data showed that PIRD patients often had immunodeficient and autoimmune features affecting multiple organ systems. Transplantation resulted in resolution of disease manifestations in more than half of the patients with an overall 5-years survival of 67%. This study, the first to encompass disorders across the PIRD spectrum, highlights the need for further research in PIRD management
Mosquitoes infected with dengue viruses in Brazil
Dengue epidemics have been reported in Brazil since 1985. The scenery has worsened in the last decade because several serotypes are circulating and producing a hyper-endemic situation, with an increase of DHF/DSS cases as well as the number of fatalities. Herein, we report dengue virus surveillance in mosquitoes using a Flavivirus genus-specific RT-Hemi-Nested-PCR assay. The mosquitoes (Culicidae, n = 1700) collected in the Northeast, Southeast and South of Brazil, between 1999 and 2005, were grouped into 154 pools. Putative genomes of DENV-1, -2 and -3 were detected in 6 mosquito pools (3.8%). One amplicon of putative DENV-1 was detected in a pool of Haemagogus leucocelaenus suggesting that this virus could be involved in a sylvatic cycle. DENV-3 was found infecting 3 pools of larvae of Aedes albopictus and the nucleotide sequence of one of these viruses was identified as DENV-3 of genotype III, phylogenetically related to other DENV-3 isolated in Brazil. This is the first report of a nucleotide sequence of DENV-3 from larvae of Aedes albopictus
Comparisons of ball possession, match running performance, player prominence and team network properties according to match outcome and playing formation during the 2018 FIFA World Cup
The aims of this study conducted in national teams during the 2018 Russia FIFA World Cup were: i) to verify the possible variations of ball possession, match running performance, player prominence, team network properties according to match outcome and playing formation; and ii) to investigate the relationships between player prominence and total distance covered according to team ball possession. Sixty-one matches were analysed over the course of the competition (n=988 player observations). Running performance was examined using total distance covered in (TDIP) and out of possession, and that travelled in different speed-range categories. Player prominence (micro) and team network properties (macro) were obtained using social network analysis where completed passes between teammates were counted (n=28019 passes). Main findings were: i) with the exception of clustering coefficients which indicate the level of interconnectivity between close teammates (win = draw > loss), match outcome was unaffected by ball possession, running and network measures ; iii) teams employing a 1‒4‒2‒3‒1 formation reported greater values for ball possession, TDIP, and micro/macro network measures compared to those playing 1‒4‒4‒2 and 1‒4‒3‒3 formations; iv) TDIP tended to be related to most player prominence variables, even though the magnitude of coefficients varied considerably according to network measures and playing positions. This study has provided additional insights into elite soccer match-play performance
Aerosol forcing of the position of the intertropical convergence zone since AD1550
The position of the intertropical convergence zone is an important control on the distribution of low-latitude precipitation. Its position is largely controlled by hemisphere temperature contrasts1, 2. The release of aerosols by human activities may have resulted in a southward shift of the intertropical convergence zone since the early 1900s (refs 1, 3, 4, 5, 6) by muting the warming of the Northern Hemisphere relative to the Southern Hemisphere over this interval1, 7, 8, but this proposed shift remains equivocal. Here we reconstruct monthly rainfall over Belize for the past 456 years from variations in the carbon isotope composition of a well-dated, monthly resolved speleothem. We identify an unprecedented drying trend since ad 1850 that indicates a southward displacement of the intertropical convergence zone. This drying coincides with increasing aerosol emissions in the Northern Hemisphere and also marks a breakdown in the relationship between Northern Hemisphere temperatures and the position of the intertropical convergence zone observed earlier in the record. We also identify nine short-lived drying events since ad 1550 each following a large volcanic eruption in the Northern Hemisphere. We conclude that anthropogenic aerosol emissions have led to a reduction of rainfall in the northern tropics during the twentieth century, and suggest that geographic changes in aerosol emissions should be considered when assessing potential future rainfall shifts in the tropics
Multiple effects of toxins isolated from Crotalus durissus terrificus on the hepatitis C virus life cycle
Hepatitis C virus (HCV) is one of the main causes of liver disease and transplantation worldwide. Current therapy is expensive, presents additional side effects and viral resistance has been described. Therefore, studies for developing more efficient antivirals against HCV are needed. Compounds isolated from animal venoms have shown antiviral activity against some viruses such as Dengue virus, Yellow fever virus and Measles virus. In this study, we evaluated the effect of the complex crotoxin (CX) and its subunits crotapotin (CP) and phospholipase A2 (PLA2-CB) isolated from the venom of Crotalus durissus terrificus on HCV life cycle. Huh 7.5 cells were infected with HCVcc JFH-1 strain in the presence or absence of these toxins and virus was titrated by focus formation units assay or by qPCR. Toxins were added to the cells at different time points depending on the stage of virus life cycle to be evaluated. The results showed that treatment with PLA2-CB inhibited HCV entry and replication but no effect on HCV release was observed. CX reduced virus entry and release but not replication. By treating cells with CP, an antiviral effect was observed on HCV release, the only stage inhibited by this compound. Our data demonstrated the multiple antiviral effects of toxins from animal venoms on HCV life cycle
Hematopoietic stem cell transplantation for CD40 ligand deficiency : results from an EBMT/ESID-IEWP-SCETIDE-PIDTC Study
Indicadores de produção e qualidade da fibra do algodoeiro fertirrigado com água residuária sanitária
- …