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2.
Int J Tuberc Lung Dis ; 27(9): 688-693, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37608478

RESUMO

BACKGROUND: TB is an infectious disease with a worldwide impact. TB is closely associated with social and housing conditions, exerting a significant impact on the prison population, which is particularly susceptible to the disease. Evidence suggests that the COVID-19 pandemic has exacerbated social vulnerability. This study therefore aimed to analyse the impact of the pandemic on the diagnosis of new cases of TB in the Brazilian prison population in the years 2020 and 2021.METHODS: This is an ecological study involving cases of TB recorded in the prison population of Brazil from 2015 to 2021. Data were collected from the Brazil's Information System for Notifiable Diseases.RESULTS: The incidence of TB in the prison population in Brazil fell from 1,005.9/100,000 population between 2015 and 2019 to 852.3/100,000 population between 2020 and 2021. In 2021, there was a deficit of 539 cases (-7.6%) compared to what was expected for the year. In 2020, there was a 10% reduction in TB diagnoses in January and February, reaching 3.8% in March. A negative percentage was observed in most of the subsequent months. In 2021, the year began with a 21.6% decline in January, returning to positive values only in August and September.CONCLUSION: The first years of the COVID-19 pandemic resulted in underdiagnosis of TB in the Brazilian prison population.


Assuntos
COVID-19 , Pandemias , Prisioneiros , Tuberculose , COVID-19/epidemiologia , COVID-19/prevenção & controle , Pandemias/prevenção & controle , Brasil/epidemiologia , Tuberculose/diagnóstico , Tuberculose/epidemiologia , Incidência , Prevalência , Controle de Infecções , Humanos , Populações Vulneráveis
4.
Epidemiol Infect ; 148: e288, 2020 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-33256878

RESUMO

This study aimed to analyse the spatial-temporal distribution of COVID-19 mortality in Sergipe, Northeast, Brazil. It was an ecological study utilising spatiotemporal analysis techniques that included all deaths confirmed by COVID-19 in Sergipe, from 2 April to 14 June 2020. Mortality rates were calculated per 100 000 inhabitants and the temporal trends were analysed using a segmented log-linear model. For spatial analysis, the Kernel estimator was used and the crude mortality rates were smoothed by the empirical Bayesian method. The space-time prospective scan statistics applied the Poisson's probability distribution model. There were 391 COVID-19 registered deaths, with the majority among ⩾60 years old (62%) and males (53%). The most prevalent comorbidities were hypertension (40%), diabetes (31%) and cardiovascular disease (15%). An increasing mortality trend across the state was observed, with a higher increase in the countryside. An active spatiotemporal cluster of mortality comprising the metropolitan area and neighbouring cities was identified. The trend of COVID-19 mortality in Sergipe was increasing and the spatial distribution of deaths was heterogeneous with progression towards the countryside. Therefore, the use of spatial analysis techniques may contribute to surveillance and control of COVID-19 pandemic.


Assuntos
COVID-19/mortalidade , Fatores Etários , Idoso , Teorema de Bayes , Brasil/epidemiologia , COVID-19/complicações , Doenças Cardiovasculares/complicações , Doenças Cardiovasculares/epidemiologia , Cidades , Análise por Conglomerados , Comorbidade , Complicações do Diabetes/epidemiologia , Escolaridade , Feminino , Humanos , Hipertensão/complicações , Hipertensão/epidemiologia , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Método de Monte Carlo , Fatores Raciais , Fatores de Risco , Saúde da População Rural , Fatores Sexuais , Análise Espacial , Análise Espaço-Temporal , Fatores de Tempo
6.
J Eur Acad Dermatol Venereol ; 33(8): 1581-1590, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30903718

RESUMO

BACKGROUND: Despite the global decline in the detection of leprosy cases, its incidence has remained unchanged in certain settings and requires the determination of the factors linked to its persistence. We examined the spatial and space-time distribution of leprosy and the influence of social vulnerability on the occurrence of the disease in an endemic area of Northeast Brazil. METHODS: We performed an ecological study of all leprosy cases reported by Sergipe state, Northeast Brazil from 2001 to 2015, to examine the association of the Social Vulnerability Index and the prevalence and persistence of leprosy among the State's municipalities. Socio-economic and leprosy surveillance information was collected from the Brazilian information systems, and a Bayesian empirical local model was used to identify fluctuations of the indicators. Spatial and space-time clusters were identified using scan spatial statistic tests and to measure the municipalities' relative risk of leprosy. RESULTS: Leprosy clusters and burden of disease had a strong statistical association with the municipalities' Social Vulnerability Index. Municipalities with a high social vulnerability had higher leprosy incidence, multibacillary leprosy and newly diagnosed cases with grade 2 disability than areas with low social vulnerability. CONCLUSION: Social vulnerability is strongly associated with leprosy transmission and maintenance of disease incidence. Leprosy control programmes should be targeted to the populations with high social vulnerability.


Assuntos
Hanseníase/epidemiologia , Adolescente , Adulto , Teorema de Bayes , Brasil/epidemiologia , Humanos , Fatores de Risco , Adulto Jovem
7.
Arq. bras. med. vet. zootec. (Online) ; 71(1): 211-218, jan.-fev. 2019. tab, graf
Artigo em Português | LILACS, VETINDEX | ID: biblio-989349

RESUMO

Objetivou-se estudar o efeito do ômega 3 e da vitamina B12 no espermograma, na histomorfometria dos órgãos reprodutivos e na temperaturas do corpo com termografia infravermelha em ratos Wistar. Utilizaram-se 16 ratos, em quatro grupos (n=4), que receberam injeções diárias por 30 dias, sendo: grupo controle - solução salina; grupo ômega 3 - óleo de peixe 1g/kg; grupo B12 - vitamina B12 3µg; e grupo ômega 3 + B12 - óleo de peixe 1g/kg e vitamina B12 3µg. Imagens termográficas de áreas do corpo foram obtidas. No 30º dia, os ratos foram sacrificados e realizaram-se as análises de morfologia espermática e histomorfometria. Os dados foram submetidos à análise de variância e ao teste de Tukey a 5%. A temperatura da superfície do escroto foi superior no grupo B12 (P<0,05). Não houve diferenças entre grupos (P>0,05) para temperaturas do globo ocular. Houve correlação entre temperatura da superfície do escroto e porcentagem de gota citoplasmática distal (P=0,678). A elevação da temperatura do escroto resulta no aumento da porcentagem de gotas citoplasmáticas distais. A temperatura do globo ocular não sofre influência significativa do ômega 3 e da vitamina B12. O ômega 3 reduz o epitélio seminífero, e a vitamina B12 minimiza esse efeito.(AU)


The objective of this study was to study the effect of Omega 3 and vitamin B12 on spermogram, histomorphometry of reproductive organs and body temperature with infrared thermography in Wistar rats. Sixteen rats were used in four groups (n= 4) who received daily injections for 30 days. Control Group - saline solution; Group Omega 3 - fish oil 1g/kg; Group B12 - vitamin B12 3μg and Group Omega 3 + B12 - fish oil 1g/kg and vitamin B12 3μg. Thermographic images of body were obtained. On the 30th day the rats were sacrificed and analyzes of sperm morphology and histomorphometry were performed. Data were submitted to analysis of variance and Tukey's test at 5%. The surface temperature of the scrotum was higher in group B12 (P< 0.05). There were no differences between groups (P> 0.05) for eyeball temperatures. There was a correlation between scrotal temperature and distal cytoplasmic droplet (P= 0.678). Elevation of scrotum temperature results in an increase in the percentage of distal cytoplasmic droplets. The temperature of the eyeball is not significantly influenced by Omega 3 and vitamin B12. Omega 3 reduces the seminiferous epithelium and vitamin B12 minimizes this effect.(AU)


Assuntos
Animais , Ratos , Vitamina B 12/efeitos adversos , Ácidos Graxos Ômega-3/efeitos adversos , Ratos Wistar/metabolismo , Contagem de Espermatozoides/veterinária , Termografia/veterinária
8.
J Appl Microbiol ; 123(1): 54-65, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28502107

RESUMO

AIMS: We evaluated the potential of a nanoparticle (NP) delivery system to improve methods of delivery of candidate peptide-based vaccines for Paratuberculosis in cattle. METHODS AND RESULTS: Peptides derived from Mycobacterium avium subsp. paratuberculosis (Map), and the pro-inflammatory monophosphoryl lipid A (MPLA) were incorporated in polymeric NPs based on poly (d,l-lactide-co-glycolide) (PLGA). The PLGA/MPLA NPs carriers were incubated with macrophages to examine their effects on survival and function. PLGA/MPLA NPs, with and without Map antigens, are efficiently phagocytized by macrophages with no evidence of toxicity. PLGA/MPLA NP formulations did not alter the level of expression of MHC I or II molecules. Expression of TNFα and IL12p40 was increased in Map-loaded NPs. T-cell proliferation studies using a model peptide from Anaplasma marginale demonstrated that a CD4 T-cell recall response could be elicited with macrophages pulsed with the peptide encapsulated in the PLGA/MPLA NP. CONCLUSIONS: These findings indicate PLGA/MPLA NPs can be used as a vehicle for delivery and testing of candidate peptide-based vaccines. SIGNIFICANCE AND IMPACT OF THE STUDY: These results will assist on more in depth studies on PLGA NP delivery systems that may lead to the development of a peptide-based vaccine for cattle.

9.
Eur J Histochem ; 58(1): 2228, 2014 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-24704990

RESUMO

Neuroblastoma is the most common extracranial solid malignant tumor observed during childhood. Although these tumors can sometimes regress spontaneously or respond well to treatment in infants, genetic alterations that influence apoptosis can, in some cases, confer resistance to chemotherapy or result in relapses and adversely affect prognosis for these patients. The aim of this study was to correlate immunohistochemical expression of the protein QSOX1 (quiescin sulfhydryl oxidase 1) in samples obtained from untreated neuroblastomas with the patients' clinical and pathological prognostic factors and clinical course. Neuroblastoma samples (n=23) obtained from histology blocks were arrayed into tissue microarrays and analysed by immunohistochemistry. The cases were classified according to the following clinical and pathological prognostic factors: age at diagnosis greater or less than/equal to 18 months; location of the lesion at diagnosis (abdominal or extra-abdominal); presence or absence of bone-marrow infiltration; tumor differentiation (well or poorly differentiated); Shimada histopathologic classification (favourable or unfavourable); state of the tumor extracellular matrix (Schwannian-stroma rich or poor); amplification of the MYCN oncogene; and clinical course (dead or alive with or without relapses/residual lesions). Twelve of the cases were female, 9 children were over 18 months old, 9 cases presented with extra-abdominal tumors and 9 cases exhibited tumors with unfavourable histologies. Fifteen patients underwent bone-marrow biopsy, and 4 of these were positive for metastasis. Nine patients died. The higher immunohistochemical expression of QSOX1 was more common in well-differentiated samples (P=0.029), in stroma-rich samples (P=0.029) and in samples from patients with a high prevalence of relapses/residual disease. The functions of QSOX1 include extracellular matrix maturation and the induction of apoptosis. Therefore, QSOX1 may be involved in neuroblastoma differentiation and regression and may thus function as a biomarker for identifying risk groups for this neoplasm.


Assuntos
Biomarcadores Tumorais/biossíntese , Regulação Enzimológica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Proteínas de Neoplasias/biossíntese , Neuroblastoma/enzimologia , Oxirredutases atuantes sobre Doadores de Grupo Enxofre/biossíntese , Criança , Pré-Escolar , Feminino , Humanos , Imuno-Histoquímica , Lactente , Masculino , Neuroblastoma/mortalidade , Neuroblastoma/patologia , Fatores de Risco , Análise Serial de Tecidos
10.
Plant Biol (Stuttg) ; 16(1): 215-26, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23574349

RESUMO

Scent glands, or osmophores, are predominantly floral secretory structures that secrete volatile substances during anthesis, and therefore act in interactions with pollinators. The Leguminosae family, despite being the third largest angiosperm family, with a wide geographical distribution and diversity of habits, morphology and pollinators, has been ignored with respect to these glands. Thus, we localised and characterised the sites of fragrance production and release in flowers of legumes, in which scent plays an important role in pollination, and also tested whether there are relationships between the structure of the scent gland and the pollinator habit: diurnal or nocturnal. Flowers in pre-anthesis and anthesis of 12 legume species were collected and analysed using immersion in neutral red, olfactory tests and anatomical studies (light and scanning electron microscopy). The main production site of floral scent is the perianth, especially the petals. The scent glands are distributed in a restricted way in Caesalpinia pulcherrima, Anadenanthera peregrina, Inga edulis and Parkia pendula, constituting mesophilic osmophores, and in a diffuse way in Bauhinia rufa, Hymenaea courbaril, Erythrostemon gilliesii, Poincianella pluviosa, Pterodon pubescens, Platycyamus regnellii, Mucuna urens and Tipuana tipu. The glands are comprised of cells of the epidermis and mesophyll that secrete mainly terpenes, nitrogen compounds and phenols. Relationships between the presence of osmophores and type of anthesis (diurnal and nocturnal) and the pollinator were not found. Our data on scent glands in Leguminosae are original and detail the type of diffuse release, which has been very poorly studied.


Assuntos
Fabaceae/anatomia & histologia , Flores , Odorantes , Polinização
11.
Work ; 41 Suppl 1: 4967-70, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22317488

RESUMO

The purpose of this study was to evaluate the impact of introduction a new work tool on health and productivity of manual harvesting sugarcane workers. In this study it was performed aErgonomic Work Analysis (EWA) to analyze the work tool changes.The study included sugarcane workers, drivers, fiscals, and technical's safety at work.During the analysis process, 134 questionnaires were applied,aimed to identify the constraints that such workers are submitted,to evaluate the tool introduced, in order to propose modifications to improve it.The results showed a decrease in perceived exertion and discomfort, without compromising the cut quality. The main contributions of Ergonomic Work Analysis were the possibility of bringing the logic of the worker, in order to understand the inherent real work characteristics, to the process of developing the new tool. Besides, it was also noted that this methodology, based on the analysis workers activity in a real usage, as an application tool in design projects, providing innovations from the workers perspective.


Assuntos
Agricultura/instrumentação , Ergonomia , Eficiência , Desenho de Equipamento , Humanos , Masculino , Esforço Físico , Saccharum , Análise e Desempenho de Tarefas
12.
Dig Dis Sci ; 54(3): 627-33, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18633707

RESUMO

In order to increase dietary folic acid intake and to improve nutritional status regarding folate by controlling homocysteine concentrations, ten patients with inflammatory bowel diseases (Crohn's disease in the colon and ulcerative colitis) received individualized nutritional guidance and were followed up as outpatients for 2 months. The following procedures were performed at the beginning of the study (T0), after 1 month (T1) and at the end of the study (T2): collection of anthropometric data (weight and height), dietary data (24 h diet recall), and blood under fasting condition for the determination of serum folic acid, homocysteine, C-reactive protein, and vitamin B12. Plasma folic acid deficiency was not detected but hyperhomocysteinemia was present in six individuals and C-reactive protein (CRP) was increased (>0.5 mg/dl) in seven patients. After the patients were instructed there was a significant increase in vitamin B6 intake (about 35%) and in folate intake (49.6%). Mean plasma levels of folic acid, homocysteine, and vitamin B12 did not change, but there was a significant decrease of CRP at T1, 0.36 mg dl(-1) on average (P = 0.01), which was maintained at T2. We conclude that the increased folate intake reported by this group of patients was not reflected in improved serum concentrations of folic acid and homocysteine. However, the guidelines for the patients probably induced them to choose a more adequate diet, providing nutrients that help control the inflammatory process.


Assuntos
Proteína C-Reativa/metabolismo , Ácido Fólico/administração & dosagem , Homocisteína/sangue , Doenças Inflamatórias Intestinais/dietoterapia , Adulto , Antropometria , Dieta , Feminino , Humanos , Doenças Inflamatórias Intestinais/sangue , Masculino , Pessoa de Meia-Idade , Estado Nutricional , Vitamina B 12/sangue , Adulto Jovem
13.
Vet Pathol ; 45(6): 829-41, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18984786

RESUMO

Pathogenic mycobacteria are highly adapted for survival within host mononuclear phagocytes. This is largely due to the organism's capacity to prevent macrophage activation, block phagosome acidification and maturation, and attenuate presentation of antigens to the immune system. Mycobacterium avium subsp. paratuberculosis (MAP) is one such organism that modulates the ruminant innate immune response. It is the causative agent in paratuberculosis, a chronic progressive granulomatous enteritis in ruminants. MAP initially interacts with cell membrane receptors on bovine mononuclear phagocytes and initiates cell signaling responses and phagocytosis. Mannosylated liparabinomannan (Man-LAM) is a major component of the MAP cell wall that interacts with the cell membrane of mononuclear phagocytes and may be a major virulence factor. Toll-like receptor 2 (TLR2) has been incriminated as major signaling receptor that binds to MAP and initiates signaling though the mitogen-activated protein kinase (MAPK)-p38 pathway. This pathway induces transcription of interleukin (IL)-10. Early production of IL-10 suppresses proinflammatory cytokines, chemokines, IL-12, and major histocompatability factor class-II expression. Both IL-10 dependent and IL-10 independent mechanisms appear to be involved in attenuation of phagosome acidification and phagolysosome fusion. Many of the suppressive effects of MAP on bovine mononuclear phagocytes can be reproduced by exposure of bovine monocytes to Man-LAM. Therefore, MAP Man-LAM-induced TLR2-MAPK-p38 signaling with resultant excessive IL-10 expression has emerged as one of the mechanisms by which MAP organisms suppress inflammatory, immune, and antimicrobial responses and promote their survival within host mononuclear phagocytes.


Assuntos
Mycobacterium avium subsp. paratuberculosis/fisiologia , Fagócitos/microbiologia , Animais , Bovinos , Mycobacterium avium subsp. paratuberculosis/patogenicidade , Virulência
14.
J Phys Chem B ; 110(18): 9155-63, 2006 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-16671728

RESUMO

A series of Co/x%Nb2O5/Al2O3 catalysts were prepared by anchoring niobia on an Al2O3 support at different niobia concentrations. Characterization of the structure and nature of surface active sites was attempted in order to correlate the CO hydrogenation activity of these systems with those of the Co/Al2O3 and Co/Nb2O5 catalysts. The effect of the reduction temperature on the CO hydrogenation activity and selectivity was studied, showing that interaction of cobalt and niobia surface species favored the selectivity for hydrocarbon chain growth. However, this effect is less pronounced on the niobia-promoted Co/Al2O3 compared to Co/Nb2O5 catalysts. X-ray photoelectron spectroscopy (XPS) and diffuse reflectance spectroscopy (DRS) results on Co/x%Nb2O5/Al2O3 showed prevailing amounts of Co2+ and Co3+ after calcination and reduction at 573 K, while, after reduction at 773 K, besides metallic cobalt, the Co2+ species still remains in contact with alumina, even for higher niobia loading. It seems that during this process formation and destruction of new interfaces involving Co0-NbOx sites takes place. Results suggest that Co0, Co0-Co2+, and Co0-NbOx are the active sites at the surface. The relative abundance of Co2+ species affects greatly the performance of the catalysts. DRIFTS and selectivity results suggest that these sites might be responsible for the reaction chain growth and therefore for the drastic change in the selectivity of CH4 and C5+ hydrocarbons mainly on the Co/Nb2O5 catalyst. DRIFTS results on Co/Nb2O5/Al2O3 showed the formation of -C=C- and -CH3- besides CHxO species. With increasing reduction temperature, the -C=C- species disappear while -CH3- fragments increased markedly, suggesting the formation of increasing amounts of hydrocarbons with higher chain length.

15.
Vet Pathol ; 43(2): 127-35, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16537930

RESUMO

Mycobacterium avium subsp. paratuberculosis is the causative agent of Johne's disease, a chronic granulomatous enteritis of wild and domestic ruminants. During a long subclinical period, the organism persists in the intestine despite systemic cellular and humoral immune responses. To explore the mucosal immune response in Johne's disease, we isolated mononuclear leukocytes from the ileum of cows naturally infected with M. avium subsp. paratuberculosis and from cows that were not infected. We evaluated the immunophenotype of these cells and the proliferative responses after the addition of M. avium subsp. paratuberculosis sonicate or B-cell or T-cell mitogens. Although the percentage of T cells was increased in infected cows, these cells consisted mostly of memory (CD2+CD62L-) and regulatory (CD4+CD25+) T cells. Further evidence of immune hyporesponsiveness included a decrease in the percentage of T cells with an activated phenotype and a decrease in cells expressing major histocompatibility factor class II (MHC class II). Unlike the spleen, ileal lymphocytes from infected cows failed to proliferate in response to M. avium subsp. paratuberculosis sonicate. Additionally, ileal lymphocytes from infected cows proliferated poorly in response to concanavalin A and pokeweed mitogen, suggesting generalized T cell and B cell hyporesponsiveness. These results indicate that a state of tolerance may exist in the intestine of cows subclinically infected with M. avium subsp. paratuberculosis organisms in subclinically infected cows. This effect may be induced, at least in part, by proliferation of regulatory T cells that nonspecifically suppress mucosal immune responsiveness.


Assuntos
Doenças dos Bovinos/imunologia , Imunidade nas Mucosas/imunologia , Mucosa Intestinal/imunologia , Paratuberculose/imunologia , Animais , Antígenos CD/metabolismo , Bovinos , Doenças dos Bovinos/patologia , Proliferação de Células , Feminino , Íleo/imunologia , Íleo/patologia , Leucócitos/metabolismo , Paratuberculose/patologia , Fenótipo , Baço/imunologia , Baço/patologia
16.
Emerg Med J ; 23(1): 57-8, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16373806

RESUMO

OBJECTIVES: To assess the combination of propofol and remifentanil for sedation to reduce shoulder dislocations in an ED. METHODS: Eleven patients with anterior glenohumeral dislocation were given propofol 0.5 mg/kg and remifentanil 0.5 microg/kg iv over 90 seconds and then further doses of 0.25 mg/kg and 0.25 microg/kg, respectively, if needed. Another practitioner attempted reduction using the Milch technique. RESULTS: Reduction was achieved in all patients within four minutes of giving sedation (range 0.3-4; mean 1.6). Seven required one attempt at shoulder reduction, three required two attempts, and one required three attempts. Mean time to recovery of alert status was three minutes (range 1-6). The mean pain score during the reduction was 1.7 out of 10 (range 0-5). Nine patients had full recall, one had partial recall, and one had no recall at all. Eight patients were "very satisfied" with the sedation and three were "satisfied". There were no respiratory or haemodynamic complications that required treatment. CONCLUSIONS: Propofol and remifentanil provide excellent sedation and analgesia for the reduction of anterior glenohumeral dislocation, enabling rapid recovery.


Assuntos
Sedação Consciente/métodos , Hipnóticos e Sedativos , Piperidinas , Propofol , Luxação do Ombro/terapia , Adolescente , Adulto , Combinação de Medicamentos , Serviço Hospitalar de Emergência , Feminino , Humanos , Masculino , Rememoração Mental/efeitos dos fármacos , Pessoa de Meia-Idade , Procedimentos Ortopédicos , Satisfação do Paciente , Projetos Piloto , Remifentanil
17.
Rev. ciênc. farm. básica apl ; 27(3): 221-227, 2006. tab, graf
Artigo em Inglês | LILACS | ID: lil-466204

RESUMO

It is known that the invasin molecule of Yersinia pseudotuberculosis stimulates human peripheral B cells in vitro. In this work we evaluated the in vivo role ofinvasin as polyclonal activator of B lymphocytes in the mouse experimental model, by comparing strains of Y.pseudotuberculosis expressing invasin and isogenic inv mutants. Swiss mice were infected intravenously with two strains expressing invasin (YpIII pIB1 and an isogenic virulence plasmid-cured strain, YpIII) and with two invasin mutant strains (Yp100 pIB1 and Yp100, plasmid-cured). Spleen cells were sampled on days 7, 14, 21 and 28 after infection. Immunoglobulin (Ig)-secreting spleen cells were detected by protein A plaque assay and specific antibodies were detected in sera by ELISA. The virulent strain YPIII pIB1 (wild type) did not provoke polyclonal activation of B lymphocytes in vivo. In general, fewer Ig-secreting spleen cells of all isotypes were foundin the infected animals than in the control animals. Specific IgG antibodies were detected in the sera of animals infected with all strains. The peak response occurred on the 21st day post-infection, and the Yp100 strain provoked the highest level of these antibodies. We concluded that invasin is not a polyclonal activator of murine B cells.


Assuntos
Animais , Feminino , Camundongos , Anticorpos , Linfócitos B/microbiologia , Yersinia pseudotuberculosis
18.
Rev. ciênc. farm ; 24(1): 53-60, 2003. tab, graf
Artigo em Português | LILACS | ID: lil-384502

RESUMO

O plasmídeo de virulência, comum às espécies patogênicas de Yersinia codifica um conjunto de proteínas secretadas denominadas Yops ("Yersinia outer proteins"). As "Yops" efetoras têm sido relacionadas e uma série de propriedades biológicas, incluindo resitência à fagocitose, citotoxicidade e desfosforilação de proteínas do hospedeiro. Porém, a associação das "Yops" de Yersinia com a resposta imune adaptativa do hospedeiro não está bem esclarecida. Yops secretadas por Yersinia enterocolitica O:3 provocam ativação policlonal de linfócitos B, quando inoculadas em camundongos. Neste trabalho, Yops secretadas po Y. pseudotuberculosis foram inoculadas por via intravenosa em camundongos Swiss livres de patógenos específicos (SPF), com objetivo de se verificar o papel in vivo destas proteínas sobre a ativação de linfócitos B esplênicos. Para tanto, foi determinada a cinética de células secretoras de imunoglobulinas inespecíficas e específicas dos diferentes isotipos (IgG, IgM e IgA), pela técnica de ELISPOT e pesquisada a presença de anticorpos específicos anti-Yersinia nos soros dos animais inoculados, através de ELISA. Foi verificado que ocorreu um aumento significativo apenas no número de linfócitos secretores de Igs inespecíficas do isotipo IgG no 21º dia poó-inoculação (aumento de 2,5 vezes em relação aos controles). O número de linfócitos secretores dos outros isotipos foi semelhante aos controles, com exceção de IgA, que sofreu uma diminuição de 3,1 vezes no 7º dia pós-inoculação. Quanto às células secretoras de imunoglobulinas específicas, a resposta dos animais inoculados foi muito individual. Em alguns camundongos inoculados, foram detectadas células secretoras de Igs anti-Yersinia do isotipo IgG, no 7º e 14º dia pós-inoculação e do isotipo IgM, no 7º e 28º dia pós-inoculação. Por outro lado, foram detectados anticorpos séricos anti-Yersinia foram detectados apenas no 7º dia pós-inoculação. Estes resultados demonstram que existe uma diferença na capacidade imunomoduladora das Yops secretadas por Y.pseudotuberculosis e Y.enterocolitica.


Assuntos
Animais , Ativação Linfocitária , Linfócitos B , Yersinia pseudotuberculosis , Ensaio de Imunoadsorção Enzimática
19.
Am J Respir Cell Mol Biol ; 24(2): 203-9, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11159055

RESUMO

The role of CD8 T lymphocytes in the immune response to Mycobacterium tuberculosis infection remains enigmatic, with persuasive reports of both cytolytic and noncytolytic (cytokine-mediated) responses to infection. To address the importance of the cytolytic mechanisms, mice with targeted disruptions for CD8 and perforin or with gene mutations in the CD95/ CD95L signaling pathway were exposed to pulmonary infection. All mice tested showed no differences in their ability to contain the growth of infection during the early phase of disease. As the chronic phase of the disease ensued, however, both CD8- and CD95/CD95L-deficient mice gradually lost their ability to limit bacterial growth. This was associated with a tendency toward pyogenic inflammation in the lung. This tendency was not seen in the perforin gene-disrupted mice. In CD8 gene-disrupted mice, the ability to generate interferon-gamma secreting T cells was unimpaired. Although these cells were capable of entering the lung they were unable to influence the increasing bacterial load in this organ.


Assuntos
Linfócitos T CD8-Positivos/fisiologia , Glicoproteínas de Membrana/metabolismo , Mycobacterium tuberculosis/imunologia , Tuberculose Pulmonar/imunologia , Receptor fas/metabolismo , Animais , Antígenos CD4/metabolismo , Linfócitos T CD4-Positivos/fisiologia , Doença Crônica , Ensaio de Imunoadsorção Enzimática , Proteína Ligante Fas , Citometria de Fluxo , Imunidade Inata , Interferon gama/análise , Ligantes , Pulmão/imunologia , Pulmão/microbiologia , Pulmão/ultraestrutura , Glicoproteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mycobacterium tuberculosis/patogenicidade , Transdução de Sinais , Tuberculose Pulmonar/microbiologia , Tuberculose Pulmonar/patologia , Receptor fas/genética
20.
Am J Respir Cell Mol Biol ; 23(2): 188-93, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10919985

RESUMO

In this study, we compared the course of a low-dose aerosol Mycobacterium tuberculosis infection in mice bearing gene disruptions for the beta2-microglobulin molecule, the CD8 molecule, and the CD1 molecule. Over the first 50 d of infection, the CD8- and CD1-disrupted mice were no more susceptible to infection than were the control mice. In contrast, the bacterial load in beta2-microglobulin gene-disrupted mice increased rapidly and attained much higher levels than that observed in the other gene-disrupted mice and in control mice. A second major difference between the beta2-microglobulin gene-disrupted mice and the other animals was the development of lung granulomas; both the CD8- and CD1-disrupted mice developed essentially normal granulomas except for an apparent increased lymphocyte influx in the CD8-disrupted mice. The beta2-microglobulin gene-disrupted mice, on the other hand, developed granulomas virtually devoid of lymphocytes, with these cells instead localized within prominent perivascular cuffing adjacent to the lesions. These data support the hypothesis that a beta2-microglobulin-dependent, non-CD8- and non-CD1-dependent mechanism controls the early and efficient influx of protective lymphocytes into infected lesions, and that the absence of this mechanism decreases the capacity of the animal to initially deal with pulmonary tuberculosis.


Assuntos
Linfócitos/imunologia , Tuberculose Pulmonar/imunologia , Microglobulina beta-2/fisiologia , Animais , Antígenos CD1/genética , Antígenos CD1/imunologia , Antígenos CD8/genética , Quimiocina CCL2/genética , Quimiocina CCL2/metabolismo , Feminino , Interferon gama/farmacologia , Linfócitos/citologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos , Camundongos Knockout , Mycobacterium tuberculosis/crescimento & desenvolvimento , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Tuberculose Pulmonar/microbiologia , Microglobulina beta-2/genética
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