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1.
Braz. j. infect. dis ; 25(4): 101601, 2021. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1339433

RESUMO

ABSTRACT Background: Large-scale epidemiological studies of seroprevalence of antibodies against SARS-CoV-2 often rely on point-of-care tests that provide immediate results to participants. Yet, little is known on how long rapid tests remain positive after the COVID-19 episode, or how much variability exists across different brands and even among batches of the same test. Methods: In November 2020, we assessed the sensitivity of three tests applied to 133 individuals with a previous positive PCR result between April and October. All subjects provided finger prick blood samples for two batches (A and B) of the Wondfo lateral-flow IgG/IgM test, and dried blood spot samples for the S-UFRJ ELISA test. Results: Overall sensitivity levels were 92.5% (95% CI 86.6-96.3), 63.2% (95% CI 54.4-71.4) and 33.8% (95% CI 25.9-42.5) for the S-UFRJ test, Wondfo A and Wondfo B tests, respectively. There was no evidence of a decline in the positivity of S-UFRJ with time since the diagnosis, but the two Wondfo batches showed sharp reductions to as low as 41.9% and 19.4%, respectively, for subjects with a positive PCR in June or earlier. Positive results for batch B of the rapid test were 35% to 54% lower than for batch A at any given month of diagnosis. Interpretation: Whereas the ELISA test showed high sensitivity and stability of results over the five months of the study, both batches of the rapid test showed substantial declines, with one of the batches consistently showing lower sensitivity levels than the other. ELISA tests based on dried-blood spots are an inexpensive alternative to rapid lateral-flow tests in large-scale epidemiological studies.


Assuntos
Humanos , Pessoas Mal Alojadas , Sífilis/epidemiologia , Infecções por HIV/epidemiologia , HIV-1 , Hepatite C/epidemiologia , Treponema pallidum , Brasil/epidemiologia , Anticorpos Anti-HIV , Estudos Soroepidemiológicos , Hepacivirus
2.
Rev. saúde pública (Online) ; 55: 1-11, 2021. tab, graf
Artigo em Inglês | LILACS, BBO | ID: biblio-1352161

RESUMO

ABSTRACT OBJECTIVE To describe the evolution of seropositivity in the State of Rio Grande do Sul, Brazil, through 10 consecutive surveys conducted between April 2020 and April 2021. METHODS Nine cities covering all regions of the State were studied, 500 households in each city. One resident in each household was randomly selected for testing. In survey rounds 1-8 we used the rapid WONDFO SARS-CoV-2 Antibody Test (Wondfo Biotech Co., Guangzhou, China). In rounds 9-10, we used a direct ELISA test that identifies IgG to the viral S protein (S-UFRJ). In terms of social distancing, individuals were asked three questions, from which we generated an exposure score using principal components analysis. RESULTS Antibody prevalence in early April 2020 was 0.07%, increasing to 10.0% in February 2021, and to 18.2% in April 2021. In round 10, self-reported whites showed the lowest seroprevalence (17.3%), while indigenous individuals presented the highest (44.4%). Seropositivity increased by 40% when comparing the most with the least exposed. CONCLUSIONS The proportion of the population already infected by SARS-Cov-2 in the state is still far from any perspective of herd immunity and the infection affects population groups in very different levels.


Assuntos
Humanos , SARS-CoV-2 , COVID-19 , Brasil/epidemiologia , Estudos Soroepidemiológicos , Anticorpos Antivirais
3.
Rev. saúde pública (Online) ; 54: 75, 2020. tab, graf
Artigo em Inglês | BBO, LILACS | ID: biblio-1127238

RESUMO

ABSTRACT OBJECTIVE To describe social distancing practices in nine municipalities of the state of Rio Grande do Sul, Brazil, stratified by gender, age, and educational attainment. METHODS Two sequential cross-sectional studies were conducted in the municipalities of Canoas, Caxias do Sul, Ijuí, Passo Fundo, Pelotas, Porto Alegre, Santa Cruz do Sul, Santa Maria, and Uruguaiana to estimate the population prevalence of COVID-19. The study was designed to be representative of the urban population of these municipalities. A questionnaire including three questions about social distancing was also administered to the participants. Here, we present descriptive analyses of social distancing practices by subgroups and use chi-square tests for comparisons. RESULTS In terms of degree of social distancing, 25.8% of the interviewees reported being essentially isolated and 41.1% reported being quite isolated. 20.1% of respondents reported staying at home all the time, while 44.5% left only for essential activities. More than half of households reported receiving no visits from non-residents. Adults aged 20 to 59 reported the least social distancing, while more than 80% of participants aged 60 years or older reported being essentially isolated or quite isolated. Women reported more stringent distancing than men. Groups with higher educational attainment reported going out for daily activities more frequently. CONCLUSIONS The extremes of age are more protected by social distancing, but some groups remain highly exposed. This can be an important limiting factor in controlling progression of the COVID-19 pandemic.


RESUMO OBJETIVO Descrever práticas de distanciamento social em nove municípios do Rio Grande do Sul por sexo, idade, escolaridade e cidade. MÉTODOS Foram realizados dois estudos transversais sequenciais representativos da população urbana nos municípios de Canoas, Caxias do Sul, Ijuí, Passo Fundo, Pelotas, Porto Alegre, Santa Cruz do Sul, Santa Maria e Uruguaiana com o intuito de estimar a prevalência populacional de Covid-19. Foi aplicado questionário contendo três perguntas sobre distanciamento social, cujas práticas foram submetidas a análises descritivas por subgrupos. Os dados foram comparados por testes qui-quadrado. RESULTADOS Em termos de grau de distanciamento social, 25,8% dos entrevistados relataram estar praticamente isolados e 41,1% indicam praticar bastante distanciamento. Relataram ficar em casa o tempo todo 20,1% dos entrevistados, e 44,5% informam que saem apenas para atividades essenciais. Mais da metade dos domicílios não recebe visitas de não moradores. O grupo que relatou menos distanciamento social foi o de adultos entre 20 e 59 anos, enquanto mais de 80% dos entrevistados com 60 anos ou mais relataram estar praticamente isolados ou fazendo bastante distanciamento. As mulheres relataram fazer mais distanciamento que os homens, e os grupos de maior escolaridade foram os que relataram sair diariamente para atividades regulares com mais frequência. CONCLUSÕES Os grupos mais jovens e mais idosos estão mais protegidos pelo distanciamento social, mas há grupos bastante expostos, o que pode ser um limitador importante no controle da progressão da epidemia de Covid-19.


Assuntos
Humanos , Masculino , Feminino , Adulto , Adulto Jovem , Pneumonia Viral/prevenção & controle , Isolamento Social , Controle de Doenças Transmissíveis/estatística & dados numéricos , Infecções por Coronavirus/prevenção & controle , Pandemias/prevenção & controle , Brasil , Estudos Transversais , Cidades , Betacoronavirus , SARS-CoV-2 , COVID-19 , Pessoa de Meia-Idade
4.
Ciênc. Saúde Colet. (Impr.) ; 25(supl.1): 2395-2401, Mar. 2020. tab, graf
Artigo em Português | LILACS | ID: biblio-1101064

RESUMO

Resumo A COVID-19 é uma doença produzida pelo vírus SARS-CoV-2. Esse vírus se espalhou rapidamente pelo mundo, o que levou a Organização Mundial da Saúde a classificar a COVID-19 como uma emergência de saúde internacional e, posteriormente, a declará-la uma pandemia. O número de casos confirmados, no dia 11 de abril de 2020, já passa de 1.700.000, porém esses dados não refletem a real prevalência de COVID-19 na população, visto que, em muitos países, os testes são quase que exclusivamente realizados em pessoas com sintomas, especialmente os mais graves. Para definir políticas de enfrentamento, é essencial dispor de dados sobre a prevalência real de infecção na população. Este estudo tem por objetivos avaliar a proporção de indivíduos já infectados pelo SARS-CoV-2 no Rio Grande do Sul, Brasil, analisar a velocidade de expansão da infecção e estimar o percentual de infectados com e sem sintomas. Serão realizados quatro inquéritos sorológicos repetidos a cada 15 dias, com amostragem probabilística de nove cidades sentinela, em todas as sub-regiões do Estado. As entrevistas e testes ocorrerão no âmbito domiciliar. Serão utilizados testes rápidos para detecção de anticorpos, validados previamente ao início da coleta de dados.


Abstract COVID-19, the disease produced by the virus SARS-CoV-2, has spread quickly throughout the world, leading the World Health Organization to first classify it as an international health emergency and, subsequently, declaring it pandemic. The number of confirmed cases, as April 11, surpassed 1,700,000, but this figure does not reflect the prevalence of COVID-19 in the population as, in many countries, tests are almost exclusively performed in people with symptoms, particularly severe cases. To properly assess the magnitude of the problem and to contribute to the design of evidence-based policies for fighting COVID-19, one must accurately estimate the population prevalence of infection. Our study is aimed at estimating the prevalence of infected individuals in the state of Rio Grande do Sul, Brazil, to document how fast the infection spreads, and to estimate the proportion of infected persons who present or presented symptoms, as well as the proportion of asymptomatic infections. Four repeated serological surveys will be conducted in probability samples of nine sentinel cities every two weeks. Tests will be performed in 4,500 participants in each survey, totaling18,000 interviews. Interviews and tests will be conducted at the participants' household. A rapid test for the detection of antibodies will be used; the test was validated prior to the beginning of the fieldwork.


Assuntos
Humanos , Pneumonia Viral/epidemiologia , Infecções por Coronavirus/epidemiologia , Vigilância de Evento Sentinela , Técnicas de Laboratório Clínico/estatística & dados numéricos , Infecções Assintomáticas/epidemiologia , Pandemias , Betacoronavirus/imunologia , Pneumonia Viral/transmissão , Fatores de Tempo , Brasil/epidemiologia , Prevalência , Infecções por Coronavirus , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/transmissão , Técnicas de Laboratório Clínico/métodos , Técnicas de Laboratório Clínico/ética , Betacoronavirus , Anticorpos Antivirais/sangue
5.
Mem. Inst. Oswaldo Cruz ; 113(2): 126-129, Feb. 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-894898

RESUMO

Leptospira interrogans serovar Canicola is one of the most important pathogenic serovars for the maintenance of urban leptospirosis. Even though it is considered highly adapted to dogs, serovar Canicola infection has already been described in other animals and even a few human cases. Here, we present the genomic characterisation of two Brazilian L. interrogans serovar Canicola strains isolated from slaughtered sows (L0-3 and L0-4) and their comparison with human strain Fiocruz LV133. It was observed that the porcine serovar Canicola strains present the genetic machinery to cause human infection and, therefore, represent a higher risk to public health. Both human and porcine serovar Canicola isolates also presented sequences with high identity to the Chinese serovar Canicola published plasmids pGui1 and pGui2. The plasmids identification in the Brazilian and Chinese serovar Canicola strains suggest that extra-chromosomal elements are one more feature of this serovar that was previously unnoticed.


Assuntos
Animais , Genoma Bacteriano , Leptospira interrogans serovar canicola/isolamento & purificação , Leptospira interrogans serovar canicola/genética , Suínos/microbiologia , Tipagem Molecular
6.
Mem. Inst. Oswaldo Cruz ; 113(5): e170444, 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-894927

RESUMO

Leptospira inadai is classified as a species of the Leptospira intermediate group that has been poorly studied due to its apparent insignificance to human and animal health. Nevertheless, over the last two decades the species has been described in human cases in India and in carrier animals in Ecuador. Here, we present the first identification and genomic characterisation of L. inadai serogroup Lyme isolated from captured rodent in Brazil. Even though the M34/99 strain was not pathogenic for hamsters, it was able to establish renal colonisation. The M34/99 strain presented high similarity with L. inadai serogroup Lyme human reference indicating that animal strain could also infect humans, although it does not represent high risk of severe disease. An extrachromosomal sequence was also identified in M34/99 strain and presented high identity with previously described L. inadai phage LinZ_10, suggesting that phage-like extrachromosomal sequence may be another feature of this understudied species.


Assuntos
Animais , Ratos , Genoma Bacteriano/genética , Leptospira/classificação , Especificidade da Espécie
7.
Mem. Inst. Oswaldo Cruz ; 111(8): 539-541, Aug. 2016. tab, graf
Artigo em Inglês | LILACS | ID: lil-789000

RESUMO

Leptospira kirschneri is one of the pathogenic species of the Leptospira genus. Human and animal infection from L. kirschneri gained further attention over the last few decades. Here we present the isolation and characterisation of Brazilian L. kirschneri serogroup Pomona serovar Mozdok strain M36/05 and the comparative genomic analysis with Brazilian human strain 61H. The M36/05 strain caused pulmonary hemorrhagic lesions in the hamster model, showing high virulence. The studied genomes presented high symmetrical identity and the in silico multilocus sequence typing analysis resulted in a new allelic profile (ST101) that so far has only been associated with the Brazilian L. kirschneri serogroup Pomona serovar Mozdok strains. Considering the environmental conditions and high genomic similarity observed between strains, we suggest the existence of a Brazilian L. kirschneri serogroup Pomona serovar Mozdok lineage that could represent a high public health risk; further studies are necessary to confirm the lineage significance and distribution.


Assuntos
Animais , Ratos , DNA Bacteriano/genética , Genoma Bacteriano/genética , Leptospira/genética , Cricetinae , Leptospira/patogenicidade , Tipagem de Sequências Multilocus , Sorogrupo , Sorotipagem
8.
Mem. Inst. Oswaldo Cruz ; 110(8): 989-995, Dec. 2015. tab, graf
Artigo em Inglês | LILACS | ID: lil-769835

RESUMO

Leptospirosis is a zoonotic disease caused by pathogenic spirochetes of theLeptospira genus. Vaccination with bacterins has severe limitations. Here, we evaluated the N-terminal region of the leptospiral immunoglobulin-like B protein (LigBrep) as a vaccine candidate against leptospirosis using immunisation strategies based on DNA prime-protein boost, DNA vaccine, and subunit vaccine. Upon challenge with a virulent strain ofLeptospira interrogans, the prime-boost and DNA vaccine approaches induced significant protection in hamsters, as well as a specific IgG antibody response and sterilising immunity. Although vaccination with recombinant fragment of LigBrep also produced a strong antibody response, it was not immunoprotective. These results highlight the potential of LigBrep as a candidate antigen for an effective vaccine against leptospirosis and emphasise the use of the DNA prime-protein boost as an important strategy for vaccine development.


Assuntos
Animais , Cricetinae , Feminino , Antígenos de Bactérias/imunologia , Proteínas de Bactérias/imunologia , Vacinas Bacterianas/imunologia , Leptospira/imunologia , Leptospirose/prevenção & controle , Vacinação/métodos , Adjuvantes Imunológicos , Biópsia , Chlorocebus aethiops , Sequência Conservada , Ensaio de Imunoadsorção Enzimática , Imunidade Humoral/imunologia , Imunoglobulina A/genética , Imunoglobulina A/imunologia , Imunoglobulina G/imunologia , Imunoglobulinas/genética , Imunoglobulinas/imunologia , Rim/patologia , Leptospirose/imunologia , Pulmão/patologia , Mesocricetus , Análise de Sobrevida , Células Vero , Vacinas de DNA/imunologia , Vacinas Sintéticas/imunologia , Vacinas Sintéticas/microbiologia
9.
Mem. Inst. Oswaldo Cruz ; 110(1): 134-137, 03/02/2015. graf
Artigo em Inglês | LILACS | ID: lil-741614

RESUMO

We studied the feasibility of using halloysite clay nanotubes (HNTs) and carboxyl-functionalised multi-walled carbon nanotubes (COOH-MWCNTs) as antigen carriers to improve immune responses against a recombinant LipL32 protein (rLipL32). Immunisation using the HNTs or COOH-MWCNTs significantly increased the rLipL32-specific IgG antibody titres (p < 0.05) of Golden Syrian hamsters. None of the vaccines tested conferred protection against a challenge using a virulent Leptospira interrogans strain. These results demonstrated that nanotubes can be used as antigen carriers for delivery in hosts and the induction of a humoral immune response against purified leptospiral antigens used in subunit vaccine preparations.


Assuntos
Carboidratos da Dieta/análise , Fibras na Dieta/análise , Qualidade dos Alimentos , Inspeção de Alimentos/métodos , Frutas/química , Modelos Biológicos , Malus/química , Calibragem , Produtos Agrícolas/química , Produtos Agrícolas/crescimento & desenvolvimento , Produtos Agrícolas/metabolismo , Dinamarca , Carboidratos da Dieta/metabolismo , Fibras na Dieta/metabolismo , Armazenamento de Alimentos , Alimentos Geneticamente Modificados , Frutas/crescimento & desenvolvimento , Frutas/metabolismo , Análise dos Mínimos Quadrados , Modelos Lineares , Malus/crescimento & desenvolvimento , Malus/metabolismo , Análise de Regressão , Reprodutibilidade dos Testes , Solubilidade , Espectroscopia de Luz Próxima ao Infravermelho
10.
Braz. j. infect. dis ; 18(6): 643-650, Nov-Dec/2014. tab
Artigo em Inglês | LILACS | ID: lil-730414

RESUMO

Background: It is believed that Human Papillomavirus (HPV) and Human Immunodeficiency Virus coinfection contributes to increase the risk for cervical intraepithelial injuries. Several factors may contribute to cervical cancer (CC) development, including genetic variants such as TP53 and MDM2 gene polymorphisms. Materials and methods: A hundred HIV-infected women were examined for HPV detection and its genotypes, as well as the frequencies of the SNPs Arg72Pro and SNP309 and their associations with CC risk factors. Nested Polymerase Chain Reaction (nPCR) was used for HPV detection and PCR-RFLP for TP53 and MDM2 SNP309 genotyping. Results: HPV DNA was detected in 68% of samples. A higher frequency of low-risk HPV genotypes (66.7%) was observed when compared to high-risk genotypes (33.3%). Nine different HPV genotypes were identified, with the highest prevalence of HPV-6, followed by HPV-16 and 31. p53 Arg72Arg and SNP309 TG genotype were the most prevalent. HPV genotyping was performed by sequencing. Conclusion: The data obtained suggest that HIV-infected women are more susceptible to be infected by low-risk HPV (LR-HPV) genotypes than by high-risk (HR-HPV), and Pro72Pro of TP53 gene and TG of MDM2 SNP309 genotypes apparently seem to be protective factors among HIV-infected women for HPV acquisition and HR-HPV infection, respectively, in a sample of Southern Brazilian woman. Future investigations in larger populations are necessary to better understand the potential roles of these SNPs and the behavior of non-oncogenic HPV genotypes in HIV-mediated immunosuppression cases. .


Assuntos
Adolescente , Adulto , Feminino , Humanos , Pessoa de Meia-Idade , DNA Viral/genética , Infecções por HIV/complicações , Papillomaviridae/genética , Infecções por Papillomavirus/virologia , Brasil , Estudos Transversais , Genótipo , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Infecções por Papillomavirus/complicações , Fatores Socioeconômicos
11.
Braz. j. microbiol ; 44(1): 165-170, 2013. ilus
Artigo em Inglês | LILACS | ID: lil-676904

RESUMO

Pathogenic Leptospira spp. are the etiological agents of leptospirosis, an important disease of both humans and animals. In urban settings, L. interrogans serovars are the predominant cause of disease in humans. The purpose of this study was to characterize a novel Leptospira isolate recovered from an abandoned swimming pool. Molecular characterization through sequencing of the rpoB gene revealed 100% identity with L. interrogans and variable-number tandem-repeat (VNTR) analysis resulted in a banding pattern identical to L. interrogans serogroup Icterohaemorrhagiae, serovar Copenhageni or Icterohaemorrhagiae. The virulence of the strain was determined in a hamster model of lethal leptospirosis. The lethal dose 50% (LD50) was calculated to be two leptospires in female hamsters and a histopathological examination of infected animals found typical lesions associated with severe leptospirosis, including renal epithelium degeneration, hepatic karyomegaly, liver-plate disarray and lymphocyte infiltration. This highly virulent strain is now available for use in further studies, especially evaluation of vaccine candidates.


Assuntos
Ratos , Sequência de Bases , Genoma Bacteriano , Técnicas In Vitro , Mucosa Intestinal , Leptospira interrogans serovar icterohaemorrhagiae/genética , Leptospira interrogans serovar icterohaemorrhagiae/isolamento & purificação , Reação em Cadeia da Polimerase , Área Urbana , Doença de Weil , Cricetinae , Técnicas Histológicas , Métodos , Piscinas , Virulência
12.
J Biosci ; 2011 Dec; 36 (5): 823-831
Artigo em Inglês | IMSEAR | ID: sea-161616

RESUMO

Arg72Pro SNP of p53 has been associated with many types of cancer as well as with survival and longevity. We evaluated the Arg72Pro SNP frequencies of a Brazilian birth cohort and their association with current, demographic and birth epidemiological parameters available. In 1982, all hospital births of Pelotas, southern Brazil, were identified and studied prospectively. In 2004–5, blood samples were collected and DNA extracted. PCR-RFLP was used to genotype the Arg72Pro SNP in 3794 individual samples of the Brazil birth cohort and DNA sequencing was performed to confirm the genotypes. The genotype distribution, which was in Hardy–Weinberg equilibrium, showed a predominance of the arginine amino acid with a frequency of 46.9% Arg/Arg, 42.2% Arg/Pro and 10.9% Pro/Pro. The allele frequency was 0.68 of Arginine and 0.32 of Proline. The Arg72Pro SNP genotype and allelic frequency were related to skin colour where proline amino acid was observed more among black subjects, while arginine amino acid was observed more among white subjects. The individuals without family history of cancer and those with low birth weight were associated with arginine amino acid. The Arg72Pro SNP was strongly associated with important epidemiological variables confirming that genetic profiles on cohort studies can improve our understanding of the susceptibility of diseases and its risk factors.

13.
J Biosci ; 2010 Sep; 35(3): 405-413
Artigo em Inglês | IMSEAR | ID: sea-161465

RESUMO

Neuropeptide Y (NPY) is one of the most potent stimulants of food intake in vertebrates, mammals and fi sh. However, the present knowledge about feeding behaviour in fi sh is still limited and based on studies in a few species. The Brazilian fl ounder Paralichthys orbignyanus is being considered for aquaculture, and it is important to understand the mechanisms regulating feeding in order to improve its performance in captivity. The objectives of this study were to clone NPY cDNA, evaluate the mRNA levels in different tissues of fl ounder, and also evaluate brain NPY expression to associate food intake with NPY expression levels. A 597 bp NPY cDNA was cloned from Brazilian fl ounder brain. NPY expression was detected in all the peripheral tissues analysed. No signifi cant differences were observed in brain NPY gene expression over 24 h after food intake at a temperature of 15 ± 3°C. No correlation was observed among plasma glucose, total protein, cholesterol, triglycerides and NPY expression levels during this 24 h period. On the other hand, mRNA levels were increased after two weeks of fasting at elevated temperatures. Our results suggest that NPY mRNA levels in Brazilian fl ounder are affected by temperature.

14.
J Biosci ; 2010 Mar; 35(1): 39-47
Artigo em Inglês | IMSEAR | ID: sea-161405

RESUMO

The silver catfi sh (Rhamdia quelen) is an endemic American fi sh species. The sperm of each species has its own peculiarities and biological characteristics, which infl uence the success of mass DNA transfer methods. Our objective in this study was to evaluate different sperm-mediated gene transfer (SMGT) methods to obtain transgenic silver catfi sh. Different treatments for the incorporation of a foreign pEGFP plasmid group were used: (1) dehydrated/ rehydrated (DR), (2) dehydrated/rehydrated/electroporated (DRE), (3) electroporated (E), (4) incubated with seminal plasma (INC); and (5) incubated in the absence of seminal plasma (INCSP). Sperm motility, time of activity duration (TAD), fertilization rate (FR), hatching rate (HR) and sperm morphology were also evaluated. The polymerase chain reaction (PCR) positivity rates for the presence of the transgene were: DRE 60%; DR 40%; E 25%; INC 5% and INCSP 25%. The rates of embryo EGFP expression were: DRE 63%; DR 44%; E 34%; INC 8% and INCSP 38%. The fertilization rate in the control and DRE treatments groups were higher than in the DR group, but the E, INC and INCSP treatment groups had the lowest rate. The hatching rates of the DRE, DR and control groups were higher than in the INCSP, INC and E treatment groups (P>0.05). There were no differences among the DRE and DR, E and DR, E and INCSP groups in expression and PCR positivity rates of enhanced green fl uorescent protein (EGFP) in embryos. Scanning electron microscopy also did not show any change in sperm morphology among treatment groups. To the best of our knowledge, this is the fi rst report on transgene transmission of exogenous DNA into silver catfi sh larvae through SMGT technology.

15.
Biol. Res ; 43(1): 13-18, 2010. ilus, graf
Artigo em Inglês | LILACS | ID: lil-548025

RESUMO

Mycobacterium bovis BCG has been proposed as an effective live vector for multivalent vaccines. The development of mycobacterial genetic systems to express foreign antigens and the adjuvanticity of BCG are the basis for the potential use of this attenuated mycobacterium as a recombinant vaccine vector. Stable plasmid vectors without antibiotic resistance markers are needed for heterologous antigen expression in BCG. Our group recently described the construction of a BCG expression system using auxotrophic complementation as a selectable marker. In this work, LipL32 and LigAni antigens of Leptospira interrogans were cloned and expressed in M. bovis BCG Pasteur and in the auxotrophic M. bovis BCG ΔleuD strains under the control of the M. leprae 18kDa promoter. Stability of the plasmids during in vitro growth and after inoculation of the recombinant BCG strains in hamsters was compared. The auxotrophic complementation system was highly stable, even during in vivo growth, as the selective pressure was maintained, whereas the conventional vector was unstable in the absence of selective pressure. These results confirm the usefulness of the new expression system, which represents a huge improvement over previously described expression systems for the development of BCG into an effective vaccine vector.


Assuntos
Animais , Cricetinae , Vacina BCG/imunologia , Proteínas da Membrana Bacteriana Externa/genética , Vetores Genéticos/genética , Leptospira interrogans/genética , Mycobacterium bovis/genética , Proteínas da Membrana Bacteriana Externa/imunologia , Ensaio de Imunoadsorção Enzimática , Vetores Genéticos/imunologia , Leptospira interrogans/imunologia , Lipoproteínas/genética , Lipoproteínas/imunologia , Mycobacterium bovis/imunologia , Plasmídeos/genética , Plasmídeos/imunologia
16.
Braz. j. microbiol ; 40(2): 227-230, Apr.-June 2009. tab
Artigo em Inglês | LILACS | ID: lil-520208

RESUMO

In this study, we observed the presence of antileptospiral agglutinins in freshwater turtles of two urban lakes of Pelotas, Southern Brazil. Forty animals (29 Trachemys dorbigny and 11 Phrynops hilarii) were captured and studied. Attempts to isolate leptospires from blood and urine samples were unsuccessful. Serum samples (titer > 100) reactive to pathogenic strains were observed in 11 animals. These data encourage surveys of pet turtles to evaluate the risk of transmission of pathogenic leptospires to humans.


Neste estudo, observamos a presença de aglutininas anti-Leptospira em tartarugas de água doce de dois lagos urbanos de Pelotas, Sul do Brasil. Quarenta animais (29 Trachemys dorbigny e 11 Phrynops hilarii) foram capturados e estudados. Esforços para isolar leptospiras do sangue e urina não foram bem sucedidos. Amostras de soro positivas (títulos > 100), reativas para cepas patogênicas, foram observadas em 11 animais. Estes dados encorajam inquéritos para avaliação de tartarugas como potenciais transmissoras de leptospiras patogênicas para humanos.


Assuntos
Animais , Aglutininas/análise , Lagos , Leptospira/isolamento & purificação , Leptospira/patogenicidade , Leptospirose/sangue , Leptospirose/urina , Tartarugas , Métodos , Métodos , Virulência
17.
Pesqui. vet. bras ; 29(2): 174-176, fev. 2009. tab
Artigo em Português | LILACS | ID: lil-508356

RESUMO

Capivaras (Hydrochoerus hydrochaeris) são roedores selvagens do continente americano com crescente importância comercial como fonte alternativa de carne para o consumo humano. Nessa espécie, os estudos sobre a soroprevalência da infecção leptospiral são escassos e restritos aos espécimes de vida livre. Relatamos aqui reações positivas para anticorpos aglutinantes anti-leptospiras em 27,3 por cento (6/22) das capivaras abatidas em um frigorífico do Rio Grande do Sul. Os níveis mais altos de anticorpos sugerem infecção pelo sorogrupo Australis devido à reação para uma cepa de referência do sorovar Bratislava e para um isolado canino local do sorovar Australis, caracterizado como Leptospira noguchii. Esses resultados ressaltam que considerável parcela de capivaras criadas em cativeiro podem funcionar como reservatório de leptospiras patogênicas e chamam atenção para o risco ocupacional dos trabalhos que envolvem a criação e o abate dessa espécie animal.


Capybaras (Hydrochoerus hydrochaeris) are wild rodents from the American Continent with increasing importance as a commercial alternative source of meat for human consumption. Studies on seroprevalence for leptospiral infection are scarce and restricted to free living capybaras. We report detection of agglutinating antibodies against leptospires in 27 percent (6/22) of all animals in a slaughterhouse from Rio Grande do Sul. The highest antibody titers predicted Australis as the infecting serogroup due to reactions against a reference strain of serovar Bratislava and a canine local isolate of serovar Australis, characterized as Leptospira noguchii. The data presented in this report highlight that a considerable fraction of capybaras in captivity may behave as reservoir for pathogenic leptospires emphasizing the occupational risk of those who deal with animal farming and slaughter.


Assuntos
Animais , Aglutininas , Leptospira , Leptospirose , Roedores , Estudos Soroepidemiológicos
18.
J Biosci ; 2008 Sep; 33(3): 355-63
Artigo em Inglês | IMSEAR | ID: sea-110724

RESUMO

A new galactose-specific lectin was purified from seeds of a Caesalpinoideae plant, Bauhinia variegata, by affinity chromatography on lactose-agarose. Protein extracts haemagglutinated rabbit and human erythrocytes (native and treated with proteolytic enzymes), showing preference for rabbit blood treated with papain and trypsin. Among various carbohydrates tested, the lectin was best inhibited by D-galactose and its derivatives, especially lactose. SDS-PAGE showed that the lectin, named BVL, has a pattern similar to other lectins isolated from the same genus, Bauhinia purpurea agglutinin (BPA). The molecular mass of BVL subunit is 32 871 Da, determined by MALDI-TOF spectrometry. DNA extracted from B.variegata young leaves and primers designed according to the B. purpurea lectin were used to generate specific fragments which were cloned and sequenced, revealing two distinct isoforms. The bvl gene sequence comprised an open reading frame of 876 base pairs which encodes a protein of 291 amino acids. The protein carried a putative signal peptide. The mature protein was predicted to have 263 amino acid residues and 28 963 Da in size.


Assuntos
Sequência de Aminoácidos , Animais , Bauhinia/química , Galactose/metabolismo , Hemaglutinação , Humanos , Dados de Sequência Molecular , Lectinas de Plantas/química , Coelhos , Sementes/química , Análise de Sequência de DNA , Especificidade da Espécie
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