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1.
Braz. j. biol ; 82: e241110, 2022. tab, graf
Artigo em Inglês | LILACS-Express | MEDLINE, LILACSEXPRESS | ID: biblio-1278500

RESUMO

Abstract Plasmodium vivax is the most common human malaria parasite in Asian countries including Pakistan. Present study was designed to explore the genetic diversity of plasmodium vivax genotypes based on Pvmsp-3α and Pvmsp-3βgenes using allelic specific nested PCR and RFLP assays markers from field isolates in district Mardan, Pakistan. Blood samples of 200 P. vivax malarial patients were collected after taking their written informed consent. Genetic diversity in nested PCR products was determined by Restriction Fragment Length Polymorphism (RFLP) utilizing Alu1 and PstI restriction enzymes for alpha and beta gene products digestion, respectively. For analysis the genetic diversity of the sub allelic variants of Pvmsp3α and Pvmsp3β genes, Chi-Square test was performed by utilizing Minitab programming software 18. The P value 0.05 was considered as statistically significant. For Pvmsp-3α genes after gel electrophoresis of digested products, four distinct genotypes were obtained from total of 50 samples; type A: 35 (70%) (1.5-2.0 kb), 12 of type B (24%) (1.5-1.7 kb), 2 of type C (4%) (0.5-1.5) and one for type D (2%) (0.5-0.65 kb) which could be characterized into 9 allelic pattern (A1-A4, B1-B3, C1, D), in which A3 remained the most predominant. For Pvmsp-3βgenes, three distinct genotypes were obtained from 50 samples; 40(80%) of type A (1.5-2.5 kb), 9 (18%) of type B (1.0-1.5kb) and 1(2%) of type C (0.65 kb) which could be characterized into 6 allelic patterns (A1-A3, B1-B2, and C1). Most dominant one in Type A was A1 alleles which were noted (46%), while in Type B, the most dominant were B1 (10%).This study is the first ever report of molecular epidemiology and genetic variation in Pvmsp-3α and Pvmsp-3β genes of P. vivax isolates by using PCR/RFLP from District Mardan and showed a remarkable level of genetic diversity in the studied genes of circulating parasites in the study area. The results of this study will contribute in future studies about the genetic structure of parasite and vaccine development against the malaria.


Resumo O Plasmodium vivax é o parasita da malária humana mais comum nos países asiáticos, incluindo o Paquistão. O presente estudo foi desenhado para explorar a diversidade genética de genótipos de Plasmodium vivax baseados nos genes Pvmsp-3α e Pvmsp-3β, usando marcadores de ensaios alélicos nested PCR e RFLP de isolados de campo no distrito de Mardan, Paquistão. Amostras de sangue de 200 pacientes com malária por P. vivax foram coletadas após assinatura do termo de consentimento livre e esclarecido. A diversidade genética em produtos de PCR nested foi determinada por polimorfismo de fragmento de restrição (RFLP) utilizando as enzimas de restrição Alu1 e PstI para a digestão dos produtos dos genes alfa e beta, respectivamente. Para análise da diversidade genética das variantes subalélicas dos genes Pvmsp3α e Pvmsp3β, o teste Qui-quadrado foi realizado utilizando o software de programação Minitab 18. O valor P = 0,05 foi considerado estatisticamente significativo. Para os genes Pvmsp-3α, após eletroforese em gel de produtos digeridos, quatro genótipos distintos foram obtidos de um total de 50 amostras; tipo A: 35 (70%) (1,5-2,0 kb), 12 do tipo B (24%) (1,5-1,7 kb), 2 do tipo C (4%) (0,5-1,5) e um para o tipo D (2%) (0,5-0,65 kb), que podem ser caracterizados em nove padrões alélicos (A1-A4, B1-B3, C1, D), em que A3 permaneceu como o mais predominante. Para Pvmsp-3βgenes, três genótipos distintos foram obtidos a partir de 50 amostras; 40 (80%) do tipo A (1,5-2,5 kb), 9 (18%) do tipo B (1,0-1,5 kb) e 1 (2%) do tipo C (0,65 kb), que podem ser caracterizados em seis padrões alélicos (A1-A3, B1-B2 e C1). Os mais dominantes no tipo A foram o alelo A1, observados em 46%, enquanto, no tipo B, os mais dominantes foram B1 (10%). Este estudo é o primeiro relato de epidemiologia molecular e variação genética em Pvmsp-3α. Os genes Pvmsp-3β de isolados de P. vivax utilizando PCR/RFLP do Distrito Mardan mostraram um nível notável de diversidade genética nos genes estudados de parasitas circulantes na área de estudo. Os resultados desse estudo contribuirão em estudos futuros sobre a estrutura genética do parasita e o desenvolvimento de vacinas contra a malária.

2.
Braz. j. biol ; 82: e243283, 2022. tab, graf
Artigo em Inglês | LILACS-Express | MEDLINE, LILACSEXPRESS | ID: biblio-1278505

RESUMO

ABSTRACT Infectious agents cause serious diseases in humans worldwide and are responsible for the high rate of morbidity and mortality. The prevalence and epidemiology of infectious disease (HCV) in the hospital visited patients referred by the physicians through the initial findings and their associated risk factors were studied in Swat. The data of 174 infected patients were collected during the period of 2015 to 2017 from two clinical laboratories of Tehsil Matta Swat. Inform consent form was taken before blood collection. After taking informed consent blood samples were collected and ICT test was performed and then ICT positive cases were conform through PCR. A total of 174 ICT positive samples [106 male and 68 females] were included in this study. Age was considered from 10 to 72 years. Of the 174 ICT strip positive, 99 [63 males, 36 females] were confirmed through PCR. The prevalence rate was recorded 56.89%. I.V/I.M injection was recorded in 100% of the individuals. Visits to the barber shop was reported in (58%) of the individuals, married individuals were (81.0), surgical operation was reported in (44.8%), sharing toothbrush was observed in (29.9%), piercing was reported in (39.7%), family history was reported in (26.4%), dental treatment was observed in (21.8%), jaundice were (13.2%) and tattooing was (1.7%). Blood transfusion, surgical operations, Jaundice, family history and dental treatment were found significant risk factors for acquiring HCV infection. It was concluded that proper implementation of precautionary measures should be needed to control the spread of HCV in far near future.


RESUMO Agentes infecciosos causam doenças graves em humanos em todo o mundo, e são responsáveis pelo alto índice de morbimortalidade. A prevalência e a epidemiologia das doenças infecciosas no hospital que atendeu pacientes encaminhados pelos médicos por meio dos achados iniciais e seus fatores de risco associados foram estudadas em Peshawar. Os dados de 174 pacientes infectados foram coletados durante o período de 2015 a 2017 oriundos de dois laboratórios clínicos de Tehsil Matta Swat. O formulário de consentimento informado foi obtido antes da coleta de sangue. Após a obtenção do consentimento informado, foram coletadas amostras de sangue e foi realizado o teste ICT e, em seguida, os casos ICT positivos foram confirmados por PCR. Um total de 174 amostras ICT positivas [106 homens e 68 mulheres] foi incluído neste estudo. A idade considerada foi de 10 a 72 anos. Das 174 tiras de ICT positivas, 99 casos [63 homens, 36 mulheres] foram confirmados por PCR. A taxa de prevalência foi de 56,89%. A injeção IV / IM foi registrada em 100% dos indivíduos. A visita à barbearia foi relatada em (58%) dos indivíduos, os números de casados foram (81,0%), e a operação cirúrgica foi relatada em (44,8%), o compartilhamento de escova de dente foi observado em (29,9%), o piercing foi relatado em (39,7%), antecedentes familiares foram relatados em (26,4%), tratamento odontológico em (21,8%), icterícia (13,2%) e tatuagem em (1,7%). Transfusão de sangue, operações cirúrgicas, icterícia, histórico familiar e tratamento odontológico foram fatores de risco significativos para adquirir infecção por Vírus da Hepatite C (VHC). Concluiu-se que a implementação adequada de medidas de precaução deve ser necessária para controlar a propagação do VHC em um futuro próximo.

3.
Braz J Biol ; 82: e243283, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34161427

RESUMO

Infectious agents cause serious diseases in humans worldwide and are responsible for the high rate of morbidity and mortality. The prevalence and epidemiology of infectious disease (HCV) in the hospital visited patients referred by the physicians through the initial findings and their associated risk factors were studied in Swat. The data of 174 infected patients were collected during the period of 2015 to 2017 from two clinical laboratories of Tehsil Matta Swat. Inform consent form was taken before blood collection. After taking informed consent blood samples were collected and ICT test was performed and then ICT positive cases were conform through PCR. A total of 174 ICT positive samples [106 male and 68 females] were included in this study. Age was considered from 10 to 72 years. Of the 174 ICT strip positive, 99 [63 males, 36 females] were confirmed through PCR. The prevalence rate was recorded 56.89%. I.V/I.M injection was recorded in 100% of the individuals. Visits to the barber shop was reported in (58%) of the individuals, married individuals were (81.0), surgical operation was reported in (44.8%), sharing toothbrush was observed in (29.9%), piercing was reported in (39.7%), family history was reported in (26.4%), dental treatment was observed in (21.8%), jaundice were (13.2%) and tattooing was (1.7%). Blood transfusion, surgical operations, Jaundice, family history and dental treatment were found significant risk factors for acquiring HCV infection. It was concluded that proper implementation of precautionary measures should be needed to control the spread of HCV in far near future.


Assuntos
Hepacivirus , Hepatite C , Adolescente , Adulto , Idoso , Criança , Feminino , Hepatite C/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Paquistão/epidemiologia , Prevalência , Fatores de Risco , Adulto Jovem
4.
Braz J Biol ; 82: e241110, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34133560

RESUMO

Plasmodium vivax is the most common human malaria parasite in Asian countries including Pakistan. Present study was designed to explore the genetic diversity of plasmodium vivax genotypes based on Pvmsp-3α and Pvmsp-3ßgenes using allelic specific nested PCR and RFLP assays markers from field isolates in district Mardan, Pakistan. Blood samples of 200 P. vivax malarial patients were collected after taking their written informed consent. Genetic diversity in nested PCR products was determined by Restriction Fragment Length Polymorphism (RFLP) utilizing Alu1 and PstI restriction enzymes for alpha and beta gene products digestion, respectively. For analysis the genetic diversity of the sub allelic variants of Pvmsp3α and Pvmsp3ß genes, Chi-Square test was performed by utilizing Minitab programming software 18. The P value 0.05 was considered as statistically significant. For Pvmsp-3α genes after gel electrophoresis of digested products, four distinct genotypes were obtained from total of 50 samples; type A: 35 (70%) (1.5-2.0 kb), 12 of type B (24%) (1.5-1.7 kb), 2 of type C (4%) (0.5-1.5) and one for type D (2%) (0.5-0.65 kb) which could be characterized into 9 allelic pattern (A1-A4, B1-B3, C1, D), in which A3 remained the most predominant. For Pvmsp-3ßgenes, three distinct genotypes were obtained from 50 samples; 40(80%) of type A (1.5-2.5 kb), 9 (18%) of type B (1.0-1.5kb) and 1(2%) of type C (0.65 kb) which could be characterized into 6 allelic patterns (A1-A3, B1-B2, and C1). Most dominant one in Type A was A1 alleles which were noted (46%), while in Type B, the most dominant were B1 (10%).This study is the first ever report of molecular epidemiology and genetic variation in Pvmsp-3α and Pvmsp-3ß genes of P. vivax isolates by using PCR/RFLP from District Mardan and showed a remarkable level of genetic diversity in the studied genes of circulating parasites in the study area. The results of this study will contribute in future studies about the genetic structure of parasite and vaccine development against the malaria.


Assuntos
Plasmodium vivax , Proteínas de Protozoários , Variação Genética , Genótipo , Humanos , Paquistão , Plasmodium vivax/genética , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Proteínas de Protozoários/genética
5.
Int Immunol ; 13(11): 1423-32, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11675374

RESUMO

Expression of MHC class II molecules is restricted to professional antigen-presenting immune cells, but it can be induced by IFN-gamma in other cell types. Thyroid cells have been shown to induce class II expression (mainly HLA-DR) following stimulation with IFN-gamma and addition of tumor necrosis factor (TNF)-alpha synergistically enhanced this expression. Class II transactivator (CIITA) has been implicated as the master regulator of MHC class II molecules and its transcription has been shown to be regulated from four different promoters, one of which is responsible for its induction by IFN-gamma. The aim of this study was to find whether CIITA is synergistically induced by IFN-gamma and TNF-alpha in the human thyroid MRO-87-1 cell line, and to investigate the molecular mechanisms responsible for this synergism. We have demonstrated that IFN-gamma and TNF-alpha synergistically induce HLA-DRalpha and CIITA mRNAs, but prolonged incubation resulted in the inhibition of CIITA mRNA accumulation. Several potential mechanisms that could explain the synergistic effect were explored. NF-kappaB did not bind the CIITA inducible promoter and addition of SN50, which inhibits NF-kappaB translocation to the nucleus, did not change the synergistic effect. Furthermore, IFN-gamma did not induce IkappaBalpha degradation. Synergistic activation of signal transducer and activator of transcription (STAT)-1 or IFN regulating factor (IRF)-1 was not observed, and STAT-1 did not bind the CIITA inducible promoter. IRF-1, although not synergistically induced or activated, bound synergistically to its specific cis element on the CIITA type IV promoter. Thus we propose that IRF-1 binding mediates the synergistic induction of HLA-DRalpha and CIITA in thyroid cells.


Assuntos
Proteínas de Ligação a DNA/fisiologia , Interferon gama/farmacologia , Proteínas Nucleares , Fosfoproteínas/fisiologia , Transativadores/biossíntese , Fatores de Transcrição/fisiologia , Fator de Necrose Tumoral alfa/farmacologia , Sequência de Bases , Northern Blotting , Linhagem Celular Transformada , Proteínas de Ligação a DNA/análise , Genes MHC da Classe II , Antígenos HLA-DR/biossíntese , Antígenos HLA-DR/genética , Humanos , Fator Regulador 1 de Interferon , Dados de Sequência Molecular , Fosfoproteínas/análise , Regiões Promotoras Genéticas , Ligação Proteica , RNA Mensageiro/análise , Estimulação Química , Fatores de Tempo , Transativadores/genética
6.
J Urol ; 166(3): 841-4, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11490230

RESUMO

PURPOSE: Telomerase activity compensates for the erosion of chromosomes and it has been detected in a wide variety of human tumors. Cytokeratin 20, an intermediate filament of epithelial cells, is expressed particularly in the urinary tract. These 2 molecules are candidates to become markers for the detection and followup of bladder carcinoma. We evaluate whether each molecule may serve as a potential marker and whether the 2 combined would improve the detection or followup of bladder carcinoma in a noninvasive manner. MATERIALS AND METHODS: We obtained 44 morning urine samples from patients with transitional cell carcinoma patients and 26 from age matched patients with a wide variety of clinical disorders but no malignancy of any kind. A telomerase polymerase chain reaction-enzyme-linked immunosorbent assay kit was used to determine telomerase activity and cytokeratin 20 expression was determined by nested reverse transcriptase-polymerase chain reaction. RESULTS: All samples tested positive for cytokeratin 8 expression, which verified epithelial cells in the urine samples. Of the 44 transitional cell carcinoma cases of all stages and grades 37 (84.1%) were positive for telomerase activity, 36 (81.8%) were positive for cytokeratin 20 expression and 65.9% were double positive. Of the 29 controls with various clinical conditions other that malignancy 22 (75.9%) were positive for telomerase activity, 13 (44.83%) were positive for cytokeratin 20 expression and 34.6% were double positive. CONCLUSIONS: Telomerase activity and cytokeratin 20 expression are not specific for malignancy and may be detected in many nonmalignant pathological conditions. Therefore, their use as potential markers of bladder carcinoma should be carefully reevaluated.


Assuntos
Biomarcadores Tumorais , Carcinoma de Células de Transição/enzimologia , Proteínas de Filamentos Intermediários , Telomerase/metabolismo , Neoplasias da Bexiga Urinária/enzimologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Queratina-20 , Masculino
7.
J Leukoc Biol ; 69(4): 613-21, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11310848

RESUMO

The inflammatory response is marked by the release of several cytokines with multiple roles in regulating leukocyte activities, including the secretion of matrix metalloproteinases (MMPs). Although the effects of individual cytokines on monocyte MMP expression have been studied extensively, few studies have examined the influence of combinations of cytokines, which are likely present at inflammatory sites. Herein, we report our investigation of the combinatorial effects of tumor necrosis factor (TNF)-alpha and transforming growth factor (TGF)-beta on MMP-9 synthesis. We found that TGF-beta suppressed TNF-alpha-induced MMP-9 secretion by MonoMac-6 monocytic cells in a dose-dependent manner, with a maximal effect of TGF-beta observed at 1 ng/ml. Such suppression was likely regulated at the pretranslational level, because steady-state mRNA levels of TNF-alpha-induced MMP-9 were reduced by TGF-beta, and pulse-chase radiolabeling also showed a decrease in new MMP-9 protein synthesis. The suppressive effects of TGF-beta were time dependent, because short exposures to TNF-alpha before TGF-beta or simultaneous exposure to both cytokines efficiently reduced MMP-9 secretion. Expression of the tissue inhibitor of metalloproteinases (TIMP)-1 and TNF-alpha receptors was unaffected by either cytokine individually or in combination. Affinity binding with radiolabeled TGF-beta demonstrated that levels of TGF-beta receptors were not increased after preincubation with TGF-beta. Suppression of TNFalpha-induced MMP-9 secretion by TGF-beta correlated with a reduction in prostaglandin E2 (PGE2) secretion. Furthermore, the effect of TGF-beta or indomethacin on blockage of TNF-alpha-stimulated MMP-9 production was reversed by the addition of either exogenous PGE2 or the cyclic AMP (cAMP) analogue Bt2cAMP. Thus, we concluded that TGF-beta acts as a potent suppressor of TNF-alpha-induced monocyte MMP-9 synthesis via a PGE2- and cAMP-dependent mechanism. These results suggest that various combinations of cytokines that are present at inflammatory sites, as well as their balance during different stages of inflammation, may provide the signals necessary for directing MMP-mediated leukocyte activities.


Assuntos
Metaloproteinase 9 da Matriz/biossíntese , Monócitos/efeitos dos fármacos , Fator de Crescimento Transformador beta/farmacologia , Fator de Necrose Tumoral alfa/farmacologia , Bucladesina/farmacologia , Células Cultivadas , AMP Cíclico/fisiologia , Dinoprostona/biossíntese , Dinoprostona/metabolismo , Dinoprostona/farmacologia , Indução Enzimática/efeitos dos fármacos , Humanos , Indometacina/farmacologia , Inflamação , Metaloproteinase 9 da Matriz/genética , Monócitos/enzimologia , Receptores de Fatores de Crescimento Transformadores beta/análise , Receptores do Fator de Necrose Tumoral/análise , Sistemas do Segundo Mensageiro/fisiologia , Inibidor Tecidual de Metaloproteinase-1/análise
8.
Shock ; 15(4): 312-7, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11303732

RESUMO

We previously showed that serum TNFalpha bioactivity in rats is proportional to the extent of graded tissue injury caused by laparotomy, intestinal ischemia, and reperfusion and that the spleen is an important source of TNFalpha secretion in this condition. TNFalpha production varies, depending on the type and duration of tissue injury. It is also affected by other mediators, such as nitric oxide (NO). TNFalpha is known to increase NO production, but the effect of NO on the production of TNFalpha has not yet been fully elucidated. In this study we determined the levels of TNFalpha mRNA in rat organs after graded injury caused by anesthesia, laparotomy, intestinal ischemia, and reperfusion and evaluated the effects of the NO donor S-nitroso-N-acetylpenicillamine (SNAP) on it. Samples from different organs were removed, and TNFalpha gene expression was evaluated by semiquantitative RT-PCR. TNFalpha mRNA was not detected in the intestine (the ischemic organ) and in the kidney, brain, heart, or liver after all 4 experimental protocols. In the mesenteric lymph node (draining the ischemic organ) a basal level of expression of TNFalpha mRNA was detected in the control (anesthesia alone) group, which was increased significantly after ischemia. In the spleen (a remote immune organ not directly involved in the ischemia), a significant gradual increase in TNFalpha mRNA, which correlated to the severity of the experimental protocol, was observed. In the lung (a central participant in post-injury multiple organ failure), all interventions increased TNFalpha mRNA. Infusion of SNAP exerted a differential effect on TNFalpha mRNA: diminished its accumulation in the lymph node, enhanced it in the lung, and had no effect in the spleen. The divergent organ pattern of TNFalpha transcription emphasizes the importance of its localized expression, which is critical to the understanding of its autocrine and paracrine actions in ischemia and reperfusion.


Assuntos
Intestinos/irrigação sanguínea , Isquemia/metabolismo , Laparotomia/efeitos adversos , Doadores de Óxido Nítrico/farmacologia , Penicilamina/farmacologia , RNA Mensageiro/biossíntese , Traumatismo por Reperfusão/metabolismo , Circulação Esplâncnica , Fator de Necrose Tumoral alfa/genética , Anestesia Geral/efeitos adversos , Animais , Translocação Bacteriana , Pressão Sanguínea , Encéfalo/metabolismo , Encéfalo/patologia , Constrição , Regulação da Expressão Gênica , Hematócrito , Concentração de Íons de Hidrogênio , Isquemia/patologia , Lactatos/sangue , Fígado/metabolismo , Fígado/patologia , Pulmão/metabolismo , Pulmão/patologia , Linfonodos/metabolismo , Linfonodos/patologia , Masculino , Artéria Mesentérica Superior , Miocárdio/metabolismo , Miocárdio/patologia , Doadores de Óxido Nítrico/uso terapêutico , Óxido Nítrico Sintase/metabolismo , Óxido Nítrico Sintase Tipo III , Especificidade de Órgãos , Estresse Oxidativo , Penicilamina/análogos & derivados , Penicilamina/uso terapêutico , Reação em Cadeia da Polimerase , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/patologia , Baço/metabolismo , Baço/patologia , Fator de Necrose Tumoral alfa/biossíntese
9.
J Leukoc Biol ; 68(5): 737-47, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11073115

RESUMO

Tumor necrosis factor alpha (TNF-alpha) is a proinflammatory cytokine implicated in the stimulation of matrix metalloproteinase (MMP) production by several cell types. Our previous studies demonstrated that TNF-alpha avidly binds fibronectin (FN) and laminin, major adhesive glycoproteins of extracellular matrix (ECM) and basement membranes. These findings suggested that TNF-alpha complexing to insoluble ECM components may serve to concentrate its activities to distinct inflamed sites. Herein, we explored the bioactivity and possible function of ECM-bound TNF-alpha by examining its effects on MMP-9 secretion by monocytes. Immunofluorescent staining indicated that LPS-activated monocytes deposited newly synthesized TNF-alpha into ECM-FN. FN-bound TNF-alpha (FN/TNF-alpha) significantly up-regulated MMP-9 expression and secretion by the human monocytic cell line MonoMac-6 and peripheral blood monocytes. Such secretion could be inhibited by antibodies that block TNF-alpha activity and binding to its receptors TNF RI (p55) and TNF RII (p75). Cheniotaxis through ECM gels in the presence of soluble or bound TNF-alpha was inhibited by a hydroxamic acid inhibitor of MMPs (GM6001). It is interesting that, although the adhesion of MonoMac-6 cells to FN/TNF-alpha required functional activated beta1 integrins, FN/TNF-alpha-induced MMP-9 secretion was independent of binding to beta1 integrins, since MMP-9 secretion was unaffected by: (1) neutralizing nAb to alpha4, alpha5, and beta1 subunits, which blocked cell adhesion; (2) a mAb that stimulated beta1 integrin-mediated adhesion; and (3) binding TNF-alpha to the 30-kDa amino-terminal fragment of FN, which lacks the major cell adhesive binding sites. Thus, in addition to their cell-adhesive roles, ECM glycoproteins, such as FN, may play a pivotal role in presenting proinflammatory cytokines to leukocytes within the actual inflamed tissue, thereby affecting their capacities to secrete ECM-degrading enzymes. These TNF-alpha-ECM interactions may serve to limit the cytokine's availability and bioactivity to target areas of inflammation.


Assuntos
Quimiotaxia de Leucócito/efeitos dos fármacos , Fibronectinas/farmacologia , Metaloproteinase 9 da Matriz/biossíntese , Monócitos/enzimologia , Fator de Necrose Tumoral alfa/farmacologia , Animais , Bovinos , Adesão Celular/efeitos dos fármacos , Adesão Celular/fisiologia , Quimiotaxia de Leucócito/fisiologia , Matriz Extracelular/metabolismo , Matriz Extracelular/fisiologia , Fibronectinas/metabolismo , Humanos , Integrinas/fisiologia , Metaloproteinase 9 da Matriz/metabolismo , Monócitos/citologia , Monócitos/efeitos dos fármacos , Receptores do Fator de Necrose Tumoral/fisiologia , Fator de Necrose Tumoral alfa/metabolismo
10.
J Reprod Med ; 45(8): 643-8, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10986682

RESUMO

OBJECTIVE: To find a possible correlation between telomerase activity, mean telomere length and human papillomavirus (HPV) presence and type in vulvar vestibulitis. STUDY DESIGN: Twenty-two tissues excised during surgery for the treatment of severe vulvar vestibulitis and nine control tissue samples were tested for telomerase activity, mean telomere length, and HPV presence and type. RESULTS: Thirty-six percent of the tissues from vestibulitis patients were infected with HPV, mainly type 16/18, and none of the control tissue samples showed presence of HPV DNA (P < .02). Telomerase activity was detected in all tissues harboring HPV DNA, whereas only 64% of tissues without HPV DNA exhibited telomerase activity (P < .02). The mean telomere length was unchanged as compared to control samples. CONCLUSION: Telomerase activity in vestibulitis may be increased as a result of HPV infection, suggesting that HPV infection may play a role in the etiology of some cases of vulvar vestibulitis.


Assuntos
Papillomaviridae/isolamento & purificação , Telomerase/metabolismo , Telômero/fisiologia , Vulvite/enzimologia , Vulvite/virologia , Adulto , DNA Viral/análise , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Pessoa de Meia-Idade , Papillomaviridae/fisiologia , Reação em Cadeia da Polimerase , Vulvite/genética
11.
Int J STD AIDS ; 10(11): 699-702, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10563554

RESUMO

Our objective was to find a possible correlation between telomerase activity, mean telomere length and human papillomavirus (HPV) presence and type in genital condylomata acuminata. Fifteen biopsies from women with genital condylomata acuminata and nine control tissue samples were tested for telomerase activity, mean telomere length, and HPV presence and type. All condylomata exhibited telomerase activity, compared to 78% of the control samples. The mean telomere length of condylomata was significantly (P<0.002) shorter compared to telomere length in control tissue samples. All condylomata lesions were infected with HPV types 6/11, and more than half had additional infection with HPV 16/18. Mixed HPV 6/11 with 16/18 infection correlated with shorter telomeres than presence of HPV 6/11 alone in the lesions (4.68 +/- 0.44 kb vs 4.97 +/- 0.57 kb). None of the control tissue samples showed presence of HPV DNA. Telomerase activity may be a marker of proliferation rather than malignancy, whereas the mean telomere length could better serve as a marker for the progression of HPV lesions toward malignancy.


Assuntos
Condiloma Acuminado/genética , Doenças dos Genitais Femininos/genética , Telomerase/metabolismo , Telômero/ultraestrutura , Biópsia , Condiloma Acuminado/patologia , Condiloma Acuminado/virologia , DNA Viral/química , Feminino , Doenças dos Genitais Femininos/patologia , Doenças dos Genitais Femininos/virologia , Humanos , Papillomaviridae/isolamento & purificação
12.
Cancer ; 85(4): 919-24, 1999 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-10091771

RESUMO

BACKGROUND: Telomerase activity is not detectable in normal cells, and their telomers shorten until the chromosome is unable to replicate. Immortal cells have short but stable chromosomes and increased telomerase activity. Transitional cell carcinoma (TCC) has only a few useful markers of diagnostic or prognostic importance. The objective of this study was to determine whether there was a correlation between telomerase activity and the grade or stage of TCC, and whether the enzyme's activity could serve as a biochemical marker of this tumor. METHODS: The study included 29 patients with TCC. From each patient, samples of urine cells were obtained, and a cup biopsy was taken from an apparently normal area as well as from a part of the bladder tumor resected transurethrally. Control uroepithelial biopsies were taken from normal transitional cell sites from non-TCC patients. Biopsies or cells were subjected to either histologic examination or telomerase activity determination. RESULTS: Twenty-six of 29 (90%) of the tumor biopsies exhibited telomerase activity. Most of the cup biopsies were categorized as metaplastic or dysplastic, and 20 of 29 (69%) of these exhibited telomerase activity. Telomerase activity was found in 17 of 21 (81%) of the urine cells but in only 3 of 14 (21%) of control urine cells. All (10 of 10) of the uroepithelial biopsies taken from non-TCC patients did not show any telomerase activity. CONCLUSIONS: In this study, almost all tumor biopsies exhibited telomerase activity. The high incidence of telomerase activity found in cup biopsies of the malignant field uroepithelial cells from cup biopsies of TCC patients may suggest that telomerase could be activated early in carcinogenesis. A high incidence of telomerase activity was found in voided uroepithelial cells of TCC patients; however, no correlation between this activity and the histologic determination of grading and staging of the tumor was found.


Assuntos
Biomarcadores Tumorais/análise , Carcinoma de Células de Transição/química , Telomerase/análise , Neoplasias da Bexiga Urinária/química , Bexiga Urinária/patologia , Idoso , Biomarcadores Tumorais/urina , Biópsia/métodos , Carcinoma de Células de Transição/patologia , Carcinoma de Células de Transição/urina , Feminino , Humanos , Masculino , Estadiamento de Neoplasias , Telomerase/urina , Células Tumorais Cultivadas/química , Neoplasias da Bexiga Urinária/patologia , Neoplasias da Bexiga Urinária/urina
13.
Clin Exp Immunol ; 115(1): 19-25, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9933416

RESUMO

We have previously shown that abdominal surgery (explorative laparotomy) reduces the ability of lipopolysaccharide (LPS)-triggered spleen macrophages to secrete TNF-alpha. In this study we characterize possible mechanisms which could be responsible for the reduction in splenic production of TNF-alpha. Post-operative and control (unoperated) rat splenocytes or enriched splenic macrophages were cultured with LPS. Steady-state levels of TNF-alpha mRNA were determined by Northern and slot blot analyses, and validated by quantitative reverse transcriptase-polymerase chain reaction (RT-PCR). The amount of TNF-alpha protein was measured by Western blot analysis, and its biological activity was determined by the fibroblast L-929 cytotoxicity assay. Surgery induced a 12-fold inhibition in TNF-alpha activity (P < 0.02), caused up to two-fold reduction in the accumulation of TNF-alpha mRNA (P < 0.01), and suppressed TNF-alpha protein maturation into its 17-kD form in cellular extracts. Post-surgical spleen supernatants revealed mainly a band of a lower molecular weight (14 kD). Our data suggest a multilevel regulation of post-operative inhibition of TNF-alpha response to LPS, at the accumulation of mRNA, translational and secretory levels. We also suggest that the reduced bioactivity could be partially caused by a proteolytic cleavage of TNF-alpha. Since TNF-alpha is an important participant in immune responses, its reduced production and activity may be a central mechanism of post-operative immunosuppression.


Assuntos
Laparoscopia/efeitos adversos , Baço/citologia , Baço/metabolismo , Fator de Necrose Tumoral alfa/biossíntese , Fator de Necrose Tumoral alfa/metabolismo , Animais , Pressão Sanguínea , Western Blotting , Hematócrito , Ácido Láctico/sangue , Lipopolissacarídeos/farmacologia , Masculino , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Fator de Necrose Tumoral alfa/genética
14.
Thyroid ; 8(5): 361-9, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9623725

RESUMO

The consequence of autoantigen presentation by thyroid cells is dependent on the magnitude of expression of both HLA class II antigens (mainly HLA-DR) and costimulatory molecules, such as B7 (CD80 and CD86). Autoimmune thyrocytes are induced to express HLA-DR by interferon-gamma (IFN-gamma). The costimulatory signal leading to autoantibody production or cytotoxic T-cell immune response could be provided by antigen presenting cells (APCs) attracted to the thyroid by the primary autoimmune stimulus. Malignant thyrocytes can express HLA-DR antigens either constitutively, as a result of a nonimmunologic stimulus, or on induction with IFN-gamma after triggering of an immune response. However, their ability to express B7 molecules, which may determine enhanced antitumoral immune response mainly in the absence of intrathyroidal macrophages, has not yet been studied. The regulation of HLA-DR gene expression in APCs, such as B cells, is mediated by a series of short DNA consensus sequences located in the promoter, termed the W, X, and Y boxes, which bind several known transcription factors. We have previously characterized the expression of HLA-DR in four human thyroid carcinoma cell lines and found differences between constitutive and high- or moderate-induced expression of the protein and mRNA. Evaluation of B7 expression on the surface of thyroid cancer cells and understanding the mechanisms of HLA-DR gene expression may help in designing efficient immune response to thyroid tumors. Using the electrophoretic mobility shift assay (EMSA), we have demonstrated differences between the four thyroid cell lines in the binding of transcription factors to each of the three boxes. The binding to the promoter in each of the cell lines resulted in a single band, probably representing a complex of proteins formed via protein-protein interactions. Using flow cytometry we have shown that the B7 molecule was absent in the four thyroid cell lines and could not be induced by IFN-gamma. The absence of surface B7 molecules from the malignant thyroid cells may lead to either suppression of antitumoral cytotoxic T cell response or demand the cooperation of infiltrating APCs to favor immune response. Differences previously found in HLA-DR expression in the four human malignant thyroid cell lines may be explained by the variation in the binding of transcription factors to the boxes in the HLA-DRalpha promoter. The binding patterns of nuclear proteins derived from the four thyroid cell lines or from the B lymphocyte cell line--Raji--to each of the boxes or to the whole promoter exhibit similarities, thus suggesting similar DNA-protein interactions.


Assuntos
Carcinoma/metabolismo , Antígeno HLA-B7/metabolismo , Antígenos HLA-DR/genética , Antígenos HLA-DR/metabolismo , Regiões Promotoras Genéticas/fisiologia , Neoplasias da Glândula Tireoide/metabolismo , Fatores de Transcrição/metabolismo , Carcinoma/patologia , Membrana Celular/metabolismo , Sequência Consenso/fisiologia , DNA/genética , Humanos , Regiões Promotoras Genéticas/genética , Neoplasias da Glândula Tireoide/patologia , Células Tumorais Cultivadas
15.
Obstet Gynecol Surv ; 50(2): 146-54, 1995 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7731627

RESUMO

The data on the etiological factors presented here may enable us to suggest a synergism between the various factors associated with the pathogenesis of cervical cancer. Infection of the cervix by HPV 16/18 may result in persistence of viral DNA. The persistent HPV-DNA undergoes disruption at the E2 region, when integrated into the host genome. The transcriptional products E6 and E7 oncoproteins bind to and cause the degradation of p53 and Rb tumor-suppressor gene products. It is possible that, at that point, other cofactors may be involved in the progression toward a precancerous or cancerous condition. Those cofactors may include cigarette smoking, by introducing co-carcinogens to the tissue or by suppressing the local or systemic immune resistance similar to the effect of depressed immune resistance seen in AIDS or immunosuppression of transplant patients; hormones, by enhancing growth of HPV and transformation of HPV infected cells; low serum vitamin levels leading to decreased tissue resistance; or other infections causing local inflammation and the production of free radicals. CIN develops, leading eventually to cervical cancer.


Assuntos
Doenças Sexualmente Transmissíveis/complicações , Neoplasias do Colo do Útero/etiologia , Anticoncepção , Feminino , Humanos , Imunossupressão , Fatores de Risco , Fumar/efeitos adversos
16.
FEBS Lett ; 334(1): 60-4, 1993 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-8224228

RESUMO

A protein designated p27 that binds preferentially to single-stranded DNA rich in guanine tracts was purified to near homogeneity from rabbit hepatocyte non-histone protein extract. Purified p27 migrated as a 27 kDa polypeptide on denaturing SDS-PAGE and displayed a native molecular mass of approximately 155 kDa on Sephadex G-150 or Sepharose 6B-Cl gel filtration columns. Gel shift analysis indicated that maximum binding of p27 to single-stranded DNA required the presence of tracts of four or more contiguous guanine residues. The lowest found dissociation constant, 1.4 x 10(-8) M/l, was for single-stranded DNA that contained a (dG)17 run.


Assuntos
Cromatina/química , Proteínas de Ligação a DNA/isolamento & purificação , Fígado/química , Animais , Sequência de Bases , Células Cultivadas , Cromatina/isolamento & purificação , Cromatina/metabolismo , DNA , DNA de Cadeia Simples/metabolismo , Proteínas de Ligação a DNA/metabolismo , Eletroforese em Gel de Poliacrilamida , Fígado/citologia , Dados de Sequência Molecular , Coelhos
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