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1.
East Mediterr Health J ; 19(8): 698-703, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24975354

RESUMO

Case detection, diagnosis and treatment of tuberculosis 1 B) in children are challenging issues vorldwide. This study in Afghanistan aimed to evaluate paediatric TB case management, including contact investigation, at health facilities where all diagnostic processes were available. In 7 out of 8 regions of the country 1 province was selected. Documents used for management of paediatric TB cases were reviewed in 15 distinct hospitals and 8 provincial hospitals in the selected provinces. The key issues which emerged were: a low suspect rate among total outpatients (0.4%) and a very low suspect rate among children aged < 5 years; low performance of suspect management (68.5% suspects received further examinations); low utilization of other diagnostic methods; a high early defaulter rate (14.0%); and insufficient coverage of contact management (74.0%). This survey indicated that the Afghanistan national TB programme needs to develop plans to improve the quality of diagnosis, suspect management and contact management in paediatric TB cases.


Assuntos
Hospitais de Doenças Crônicas , Hospitais de Distrito , Tuberculose/tratamento farmacológico , Adolescente , Afeganistão/epidemiologia , Criança , Pré-Escolar , Humanos , Lactente , Sistema de Registros , Estudos Retrospectivos , Tuberculose/diagnóstico , Tuberculose/epidemiologia
2.
Clin Transl Oncol ; 24(3): 568-577, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34687441

RESUMO

OBJECTIVES: Recently, the standard of care for advanced urothelial cancer (UC) has been changed by developing immune-checkpoint inhibitors (ICIs). However, its response rate is limited to 20-30%. The identification of biomarkers to predict the therapeutic effects of ICIs is urgently needed. The present study explored the association between immunohistochemical biomarkers and clinical outcomes in UC patients treated with pembrolizumab. PATIENTS AND METHODS: A total of 85 patients with UC who received pembrolizumab after chemotherapy from January 2018 to May 2020 were retrospectively reviewed. Tumor tissues were obtained for immunohistochemical study from 47 out of 85 patients. The protein expressions of PD-L1, WT1, Nectin-4, CD4, CD8, Foxp3, and CD68 in tumor cells and/or tumor infiltrating lymphocytes were immunohistochemically examined. The associations between protein expressions and overall survival (OS), progression-free survival (PFS), and disease control rate (DCR) were statistically analyzed. RESULTS: Patients with positive PD-L1 in tumor cells showed significantly worse OS (Log-rank test: HR 5.146, p = 0.001, Cox regression analysis: HR 4.331, p = 0.014) and PFS (Log-rank test: HR 3.31. p = 0.022), along with significantly lower DCR (14.3%) compared to the PD-L1 negative patients (67.5%). In addition, patients with strong expression of Nectin-4 in tumor cells showed significantly higher DCR (100%) than the other patients (50%). CONCLUSION: PD-L1 expression in tumor cells was associated with poor prognosis (OS and PFS) and low DCR. Interestingly, the strong expression of Nectin-4 was correlated with high DCR. PD-L1 and Nectin-4 expression in tumor cells could be prognostic biomarkers useful for pembrolizumab in patients with advanced UC.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Antineoplásicos Imunológicos/uso terapêutico , Antígeno B7-H1/biossíntese , Carcinoma de Células de Transição/tratamento farmacológico , Carcinoma de Células de Transição/metabolismo , Moléculas de Adesão Celular/biossíntese , Neoplasias Urológicas/tratamento farmacológico , Neoplasias Urológicas/metabolismo , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
3.
Vet Comp Oncol ; 15(4): 1181-1186, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27353749

RESUMO

Reduced expression in immortalized cells (REIC/Dkk-3), a member of the human Dickkopf (Dkk) family, is a growth suppressor in human and canine mammary tumours. Mammary gland tumours are common neoplasms with high malignancy in female cats. The purpose of this study was to clone the feline REIC/Dkk-3 homolog, investigate its expression in cell lines established from feline mammary gland tumours, and test its tumour suppressor function. Western blot analysis revealed that expression of the REIC/Dkk-3 protein was reduced in feline mammary carcinoma cell lines. Forced expression of REIC/Dkk-3 induced apoptosis in feline mammary tumour cell lines. These results demonstrate that REIC/Dkk-3 expression, which is downregulated in feline mammary tumour cell lines, results in the induction of apoptosis in these cells. Our findings suggest that feline REIC/Dkk-3 represents a potential molecular target for the development of therapies against feline mammary cancers.


Assuntos
Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Animais , Apoptose , Doenças do Gato/metabolismo , Gatos , Linhagem Celular Tumoral/metabolismo , Clonagem Molecular , Feminino , Neoplasias Mamárias Animais/metabolismo
4.
Biol Psychol ; 73(2): 209-11, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16472905

RESUMO

To access the saliva level of 3-methoxy-4-hydroxy-phenylglycol (sMHPG) as an index of mental health in normal volunteers, we investigated the relationship between the sMHPG and the scores on the general health questionnaire-28 (GHQ-28). A total of 270 normal volunteers answered the GHQ-28 and the sMHPG levels were determined. The sMHPG levels in women and men were comparable. There was a significant negative correlation between the social dysfunction score on the GHQ-28 and sMHPG levels in women (P=0.0035), but not in men. Moreover, the sMHPG levels also correlated with the total GHQ-28 score (P=0.0205), the anxiety and the insomnia score (P=0.0306) in women. These data indicate a high social dysfunction score on the GHQ-28 to be associated with a reduced noradrenergic neuronal tone thus possibly reflecting psychomotor retardation in women.


Assuntos
Metoxi-Hidroxifenilglicol/metabolismo , Inventário de Personalidade/estatística & dados numéricos , Saliva/metabolismo , Adulto , Idoso , Ansiedade/fisiopatologia , Ansiedade/psicologia , Nível de Alerta/fisiologia , Transtorno Depressivo/fisiopatologia , Transtorno Depressivo/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Norepinefrina/fisiologia , Psicometria/estatística & dados numéricos , Desempenho Psicomotor/fisiologia , Valores de Referência , Fatores Sexuais , Distúrbios do Início e da Manutenção do Sono/fisiopatologia , Distúrbios do Início e da Manutenção do Sono/psicologia , Ajustamento Social , Transtornos Somatoformes/fisiopatologia , Transtornos Somatoformes/psicologia , Estatística como Assunto
5.
J Invest Dermatol ; 87(4): 515-8, 1986 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-3093594

RESUMO

Immunohistologic studies of 8 patients with squamous cell carcinoma (SCC) were undertaken using a series of monoclonal antibodies. In all of the patients, over 70% of the dermal infiltrates reacted with OKT3 and OKIal (HLA-DR), with a slight predominance of the OKT8+ suppressor/cytotoxic T subset (the mean OKT4/OKT8 ratio was 0.85). Both OKT4+ and OKT8+ subsets could be seen in contact with individual cancer cells. The percentage of OKB7+ (B) cells was less than 29% of the dermal infiltrates. Some Leu-7+ cells (less than 9% of the infiltrates) were seen in close association with individual cancer cells and none of these cells was present apart from the cancer cells. Few OKT6+ cells were observed in the papillary dermis and these had no relation to cancer cells. In the epidermis, OKT6+ dendritic cells remained within normal proportions. Staining with OKM1 revealed sporadic reactive cells. These results strongly suggest that besides T and B lymphocytes, Leu-7+ (natural killer) cells participate in a significant defense mechanism against SCC proliferation.


Assuntos
Antígenos de Neoplasias/análise , Antígenos de Superfície/análise , Carcinoma de Células Escamosas/imunologia , Células Matadoras Naturais/imunologia , Neoplasias Cutâneas/imunologia , Anticorpos Monoclonais , Antígenos de Diferenciação de Linfócitos T , Carcinoma de Células Escamosas/patologia , Diferenciação Celular , Antígenos HLA-DR/análise , Humanos , Imunidade Celular , Neoplasias Cutâneas/patologia , Linfócitos T/imunologia
6.
J Invest Dermatol ; 97(1): 80-4, 1991 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2056195

RESUMO

Polyclonal activation of lymphocytes due to an unknown cause is considered to be one of the most important findings of systemic autoimmune disorders including systemic lupus erythematosus (SLE). In order to confirm the expression of the C-Myc protooncogene in lesional skin, tissue specimens from SLE were examined by the histo in situ hybridization method and a histochemical method using a specific antibody reactive with C-Myc related products. Twenty-two cases of SLE, six cases of DLE, one case of lupus erythematosus profundus, two cases of lichen planus, and five skin specimens from healthy volunteers were selected for the examination. In the SLE group, further comparative examination of diseased skin and normal skin from the same patient, and of diseased skin in an active stage and a stable stage in the same SLE patient with renal involvement, were carried out. In most of the active SLE cases, protooncogene expression had apparently increased as compared with the expression in the groups of inactive and treated SLE, active DLE, active lichen planus, and those with healthy skin. Even in normal-appearing skin from active SLE without other organic failure, the protooncogenes were not expressed very strongly.


Assuntos
Genes myc , Lúpus Eritematoso Sistêmico/genética , Pele/metabolismo , Adolescente , Adulto , Feminino , Humanos , Lúpus Eritematoso Sistêmico/metabolismo , Masculino , Pessoa de Meia-Idade , Hibridização de Ácido Nucleico , Proteínas Proto-Oncogênicas c-myc/análise , RNA Mensageiro/análise
7.
J Invest Dermatol ; 96(4): 473-7, 1991 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1706744

RESUMO

The regulation of collagen gene expression in normal diploid human fetal fibroblasts (KMS-6 cells), and fibroblasts immortally transformed by treatment of KMS-6 with Co-60 gamma rays (KMST-6 cells) was compared to that of ones tumorigenically transformed by treatment of KMST-6 cells with Harvey murine sarcoma virus (KMST-6-Ras cells). Synthesized collagenous protein decreased to approximately 30% of that of normal fetal fibroblasts in both transformed cell lines, and the relative rate of collagen synthesis to total protein synthesis decreased about sixfold in KMST-6 cells and twelvefold in KMST-6-Ras cells. The m-RNA levels of type I collagen in both of these cell lines decreased to approximately 20% of that of the control fibroblasts, whereas type III collagen m-RNA levels decreased to only 9% of that of the control. The copy number of the collagen gene in both transformed cell lines was unaltered. The transcriptional rates of collagen alpha 1(I) and collagen alpha 1(III) in both cell lines decreased to 20% and 7% respectively of that of control. These data indicate that collagen synthesis was reduced at the transcriptional level in these transformed human fibroblasts.


Assuntos
Colágeno/genética , Fibroblastos/fisiologia , Linhagem Celular Transformada , Regulação da Expressão Gênica , Humanos , RNA/genética , RNA Mensageiro/genética , Transcrição Gênica/genética
8.
J Invest Dermatol ; 94(2): 187-90, 1990 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2299193

RESUMO

Although Werner's syndrome (WS) is a premature aging disease and its fibroblasts typically grow poorly in culture, WS may cause abnormalities in connective tissue metabolism that are seldom seen in normal aging, such as scleroderma-like skin. In a preliminary report, we described increased collagen synthesis in fibroblasts derived from two WS patients. The present study was undertaken to determine the degree of the regulation of collagen gene expression in dermal fibroblasts from two other patients. Overproduction of collagenase sensitive protein was observed in WS fibroblasts. Collagen m-RNA levels, that were determined by hybridization of RNA blots with specific cDNA were about 2 times greater than those in the control cells. These results suggest that control of collagen synthesis in WS fibroblasts is altered at the transcriptional level.


Assuntos
Colágeno/biossíntese , Fibroblastos/análise , RNA Mensageiro/análise , Síndrome de Werner/metabolismo , Síndrome de Werner/patologia , Células Cultivadas , Colágeno/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Transcrição Gênica
9.
J Invest Dermatol ; 103(3): 359-63, 1994 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8077701

RESUMO

One cause of the excessive deposition of collagen in systemic sclerosis is thought to be abnormal functioning of fibroblasts. The purpose of this study is to determine whether there is decreased expression of collagenase in systemic sclerosis fibroblasts. In this study, we analyzed collagen and collagenase expression in dermal fibroblasts derived from eight patients with systemic sclerosis and compared the findings with those from nine sex- and age-matched healthy subjects. Increased collagen synthesis accompanying enhanced mRNA levels was observed in two of eight strains, whereas all eight strains showed remarkable decreases in collagenase activity and production. There were no differences in the levels of collagenase mRNA between the systemic sclerosis strains and the normal strains. Results suggest that decreased collagenase expression is a characteristic of systemic sclerosis fibroblasts, and both increased collagen expression and decreased collagenase expression in systemic sclerosis fibroblasts may result in the excessive accumulation of collagen in patients with systemic sclerosis. It is also suggested that decreased collagenase expression is altered at translational and/or post-translational levels.


Assuntos
Colagenases/metabolismo , Escleroderma Sistêmico/enzimologia , Escleroderma Sistêmico/patologia , Pele/enzimologia , Pele/patologia , Adulto , Células Cultivadas , Feminino , Fibroblastos/enzimologia , Humanos , Immunoblotting , Pessoa de Meia-Idade
10.
J Invest Dermatol ; 89(3): 234-7, 1987 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-3305715

RESUMO

The fate of allogeneic (strains 13, 2, and JY-1) and autologous epidermal cell (EC) suspensions injected intradermally was investigated histologically in JY-1 strain guinea pigs. Epidermal cells were found to proliferate actively in the dermis and form EC nests with central keratinization. The significant reject reaction associated with necrosis of the epidermal structures was seen in due time in the animals implanted with allogeneic ECs. We attempted to assess the effect of cyclosporin A (CYA) on skin allograft survival by observing the fate of strain 13 ECs implanted intradermally into the CYA-treated JY-1. Successful prolongation of allograft survival with CYA was clearly demonstrated by this method. This is considered to be a useful experimental way for evaluation of skin allograft survival and to be suitable for routine use.


Assuntos
Sobrevivência de Enxerto , Transplante de Pele , Animais , Ciclosporinas/farmacologia , Células Epidérmicas , Epiderme/transplante , Estudos de Avaliação como Assunto , Sobrevivência de Enxerto/efeitos dos fármacos , Cobaias , Injeções Intradérmicas , Masculino , Pele/citologia , Transplante Homólogo
11.
J Invest Dermatol ; 106(4): 631-6, 1996 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8617996

RESUMO

Our previous work demonstrated that collagenase mRNA levels are increased in fibroblasts derived from patients with cutis laxa (CL). To pursue the mechanism of the upregulation of collagenase expression, we investigated transcriptional levels of the collagenase gene in CL fibroblasts. Fibroblasts cultured from the skin of three congenital CL patients were studied. Northern blot hybridization revealed 2.8- to 7.3-fold increases in collagenase mRNA levels in CL fibroblasts compared with normal cells. Nuclear run-off experiments demonstrated that the transcription rate of the collagenase gene in nuclei isolated from the same cells was 5.1- to 10.2-fold higher in the CL fibroblasts than in the controls. Transient transfection of a normal collagenase promoter-CAT construct into the cells further showed significantly enhanced transcriptional activity in CL but not in normal fibroblasts. Experiments of transient transfection of deleted or small substituted collagenase promoter-CAT constructs indicated that collagenase transcription in CL fibroblasts was activated the TPA-responsive element site of the collagenase promoter gene. Although the levels of Jun and Fos gene expression did not differ from those observed in normal fibroblasts, AP-1-binding activity, as measured by the ability to bind to an oligonucleotide containing a TPA-responsive element, was significantly elevated in CL fibroblasts as compared with normal fibroblasts. These data suggest that collagenase expression is upregulated at the transcriptional level by endogenous activation of DNA binding of AP-1 in CL fibroblasts [corrected].


Assuntos
Colagenases/genética , Cútis Laxa/enzimologia , Regulação Enzimológica da Expressão Gênica , Regiões Promotoras Genéticas , Acetato de Tetradecanoilforbol/farmacologia , Células Cultivadas , Pré-Escolar , Feminino , Fibroblastos/enzimologia , Humanos , Metaloproteinase 3 da Matriz , Metaloendopeptidases/genética , Fator de Transcrição AP-1/metabolismo , Transcrição Gênica
12.
J Invest Dermatol ; 108(5): 731-6, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9129224

RESUMO

The application of hapten to the skin of mice can induce contact sensitivity (CS). It has also been well established that draining lymph node (DLN) cells can induce CS to the hapten used for skin painting when injected into naive mice. This is true for DLN cells recovered about 24 h after skin painting with hapten. It is unclear, however, whether DLN cells recovered shortly after hapten application have the same ability. By using an adoptive transfer assay system, we examined the ability of DLN cells recovered from mice at various times after skin painting with hapten to induce CS. DLN cells harvested 18-24 h after the application of fluorescein isothiocyanate (FITC) or 2,4-dinitrofluorobenzene (DNFB) induced strong CS when injected into naive mice. DLN cells harvested 3-6 h after the application of FITC or DNFB induced either only weak or no CS but induced suppression of the subsequent immunization to the two haptens. The suppression was hapten-specific, MHC restricted, and associated with the appearance of splenic suppressor T lymphocytes. Analyses with antibodies and ultraviolet (UV) B radiation demonstrated that suppression-inducing cells in DLNs were Ia+, Thy-1(-), and functionally UV-sensitive. These data suggest that epicutaneous sensitization with hapten first induces immunologically specific suppressor activity in the draining lymph nodes, whereas immunogenic activity becomes predominant later.


Assuntos
Dermatite de Contato/imunologia , Linfonodos/citologia , Linfócitos T Reguladores/imunologia , Transferência Adotiva , Animais , Sobrevivência Celular , Epitopos , Feminino , Haptenos/imunologia , Haptenos/farmacologia , Tolerância Imunológica/imunologia , Ativação Linfocitária , Contagem de Linfócitos , Mesentério/citologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C3H , Pele/imunologia , Baço/citologia , Linfócitos T Reguladores/citologia , Linfócitos T Reguladores/efeitos da radiação , Raios Ultravioleta
13.
J Invest Dermatol ; 100(6): 771-4, 1993 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8496616

RESUMO

Gene expression of collagens VI, I, and III in Werner's syndrome was studied by measuring messenger RNA (mRNA) and protein production levels in four fibroblast strains from patients with Werner's syndrome and comparing them with age-matched healthy subjects. Levels of type VI collagen mRNA were decreased in all Werner's syndrome fibroblast strains and the decreases were in parallel in all three chains (alpha 1, alpha 2, and alpha 3) of type VI collagen. A coordinate increase of the alpha 1(I) and alpha 1(III) collagen mRNA levels was observed in three of the four Werner's syndrome fibroblast strains. However, no qualitative abnormality of these mRNA transcripts in Werner's syndrome fibroblasts were found by Northern blot analysis. Changes in type VI and type I collagen mRNA correlated well with production levels of corresponding proteins, as determined by immunologic assays. These data suggest that there are changes in expression of multiple connective tissue constituents in Werner's syndrome fibroblasts.


Assuntos
Colágeno/genética , Expressão Gênica , Síndrome de Werner/genética , Adulto , Colágeno/química , Feminino , Fibroblastos/química , Fibroblastos/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/análise , Síndrome de Werner/patologia
14.
J Invest Dermatol ; 90(3): 342-5, 1988 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-2450143

RESUMO

SSA/Ro antigen is a soluble cellular component to which antibodies are frequently produced in patients with Sjögren's syndrome and systemic lupus erythematosus. Its exact location within the cell has yet to be determined. In this study we report the expression of SSA/Ro antigen in simian virus 40 (SV40)-transformed keratinocytes. The locations of SSA/Ro, U1RNP, and DNA antigens were studied by indirect immunofluorescence using monospecific antibodies. SSA/Ro antigen was detected in both the nucleus and cytoplasm of SV40-transformed keratinocytes tested with three monospecific sera. Primary cultured keratinocytes derived from adult human skin showed localized immunofluorescent staining within the nucleus. When Ca++ concentration of the medium was switched to 0.05 mM, these cells expressed cytoplasmic SSA/Ro antigens within 48 h. Depletion of the antibody activity with insolubilized human spleen extract abolished the staining. Surface expression of this antigen could not be detected in either primary or transformed cells. Localization of U1RNP and DNA was not altered. These results indicate that expression of SSA/Ro antigen in human keratinocytes is modulated by SV40 infection and that this antigen is expressed to a greater degree in cells that are less differentiated, transformed, or proliferating.


Assuntos
Autoantígenos/análise , Transformação Celular Viral , Epiderme/imunologia , RNA Citoplasmático Pequeno , Ribonucleoproteínas , Humanos , Queratinas , Vírus 40 dos Símios
15.
J Invest Dermatol ; 97(3): 483-7, 1991 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-1651970

RESUMO

Collagen metabolism was studied in cutis laxa by analyzing collagen and collagenase gene expression in three dermal fibroblast strains from patients with congenital cutis laxa and comparing them with fibroblasts obtained from age-matched healthy subjects. Normal collagen synthetic activity was observed in the cutis laxa fibroblasts. An increased level of collagenase mRNA and unaltered levels of alpha 1(I) and alpha 1(III) collagen mRNA were found in all cutis laxa cell strains by dot blot hybridization. Reduced levels of elastin mRNA were also detected in these strains. However, no qualitative differences in these mRNA transcripts were detected between the control and cutis laxa fibroblasts by Northern blot analysis. Collagenase activity in fibroblast culture supernatants was then measured using fluorescein isothiocyanate (FITC)-labeled type I collagen. Increased collagenolytic activity in cutis laxa fibroblast culture supernatants was also found. These data suggest that increased collagenase expression of fibroblasts is related to the structural abnormality of dermal connective tissue in cutis laxa.


Assuntos
Colágeno/metabolismo , Cútis Laxa/metabolismo , Cútis Laxa/patologia , Fibroblastos/metabolismo , Colagenase Microbiana/genética , Colágeno/genética , Cútis Laxa/genética , Fibroblastos/enzimologia , Expressão Gênica , Humanos , RNA Mensageiro/análise
16.
Endocrinology ; 138(7): 2784-9, 1997 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9202218

RESUMO

Involvement of protein kinases in the stimulation of cGMP-inhibited cAMP phosphodiesterase (PDE) activity by orthovanadate (vanadate) was studied. When the fat pads were incubated with 2 mM vanadate or 10 nM insulin, the stimulation of myelin basic protein kinase (MBPK) activity in the particulate by vanadate reached a maximum at 60 min. In contrast, insulin showed a transient increase at 20 min. A 60-min incubation of the fat pads with vanadate stimulated all activities of protein tyrosine kinase (PTK), MBPK, and PDE in the particulate, in a similar dose-dependent manner. Amiloride, a PTK inhibitor, inhibited the stimulations of three enzymes by vanadate in a similar concentration range. Enzyme fractions, which were separated from the solubilized particulate, were subjected to the immunoblot analysis. A fraction of MBPK was identified to contain a major protein of mol wt (44K) and a minor one (42K), both of which are immunoreactive with a mitogen-activated protein kinase (MAPK) antibody. The partially purified PDE activity was stimulated by the addition of the partially purified MBPK. The further stimulation was observed with the PTK-activated MBPK. These results suggest that vanadate stimulates in part the PDE activity through the activation of the particulate MBPK, probably MAPKs, by PTK sensitive to vanadate.


Assuntos
3',5'-AMP Cíclico Fosfodiesterases/metabolismo , Tecido Adiposo/enzimologia , Proteínas Quinases Dependentes de Cálcio-Calmodulina/metabolismo , GMP Cíclico/farmacologia , Proteínas Tirosina Quinases/metabolismo , Vanadatos/farmacologia , 3',5'-AMP Cíclico Fosfodiesterases/isolamento & purificação , Animais , Proteínas Quinases Dependentes de Cálcio-Calmodulina/isolamento & purificação , Ativação Enzimática , Fluoretos/farmacologia , Glicerofosfatos/farmacologia , Quinase 3 da Glicogênio Sintase , Masculino , Modelos Biológicos , Compostos de Potássio/farmacologia , Proteínas Tirosina Quinases/isolamento & purificação , Ratos , Ratos Wistar
17.
Endocrinology ; 131(1): 441-6, 1992 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-1319324

RESUMO

When isolated rat fat pads were incubated with vanadate, the low Michaelis-Menten constant (Km) cAMP phosphodiesterase (PDE) activity in the microsomal fraction was increased in a time- and dose-dependent manner with vanadate. 3',5'-Cyclic GMP inhibited the vanadate-stimulated PDE activity with similar profile to the insulin-stimulated one. The stimulatory effect of vanadate was inhibited by inhibitors of tyrosine kinases such as amiloride, biochanin A, and genistein to various extents. Vanadate and insulin both showed the full effect in the absence of either K+, N+, or Ca2+ in the medium, while preincubation of the fat pads with a chelator of intracellular Ca2+ inhibited the vanadate action in a dose-dependent manner. The insulin action was not inhibited by it at tested concentrations. These results suggest that the vanadate action, in contrast to the insulin one, is dependent on the intracellular level of Ca2+. Preincubation of the fat pads with inhibitors of protein kinase C such as 1-(5-isoquinoline sulfonyl)-2-methylpiperazine (H-7) and staurosporine inhibited, in part, the vanadate action but did not inhibit the insulin one. Furthermore, vanadate increased the protein kinase C activity in fat pads but insulin did not increase. H-7 and amiloride showed a significant inhibition of stimulation of protein kinase C activity by vanadate. These results suggest that vanadate stimulates, in part, the 3',5'-cyclic GMP-inhibited low Km cAMP PDE activity in the microsomal fraction of fat pads through the activation of tyrosine kinase and protein kinase C-mediated processes.


Assuntos
3',5'-AMP Cíclico Fosfodiesterases/metabolismo , Tecido Adiposo/enzimologia , GMP Cíclico/farmacologia , Vanadatos/farmacologia , 1-(5-Isoquinolinasulfonil)-2-Metilpiperazina , Alcaloides/farmacologia , Amilorida/farmacologia , Animais , Relação Dose-Resposta a Droga , Ativação Enzimática/efeitos dos fármacos , Insulina/farmacologia , Isoquinolinas/farmacologia , Cinética , Masculino , Microssomos/enzimologia , Piperazinas/farmacologia , Proteína Quinase C/antagonistas & inibidores , Proteína Quinase C/metabolismo , Proteínas Tirosina Quinases/metabolismo , Ratos , Ratos Endogâmicos , Receptor de Insulina/efeitos dos fármacos , Receptor de Insulina/fisiologia , Estaurosporina , Vanadatos/administração & dosagem
18.
Cancer Lett ; 122(1-2): 37-42, 1998 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-9464489

RESUMO

Although it is considered that the lipoprotein metabolism in tumor plays an important role in growth and multiplication, it is not clear as to the details. Lipoprotein lipase (LPL) is a key enzyme responsible for the hydrolysis of lipoprotein-triacylglyceride. In this study, we examined the regulatory step of LPL in lipoprotein metabolism of Ehrlich ascites tumor and especially the enzyme-release from the tumor cells. When LPL was stimulated to release from the tumor cells by the low molecular weight dextran sulfate (3.2 kDa), cyclic AMP content in the tumor cells was observed to increase rapidly in a time-dependent manner up to 30 s; its maximal effect was 1.5-fold higher than the basal level of cyclic AMP. The increase in cyclic AMP content was more enhanced in the presence of isobutylmethylxanthine and was never suppressed by propranolol. Moreover, cyclic AMP-dependent protein kinase (PKA) activity in the tumor cells was also recognized to elevate in a time- and dose-dependent manner. In addition, the release of LPL activity from the tumor cells was inhibited by 2',5'-dideoxyadenosine. These results suggest that LPL in the tumor cells is released through a pathway involving an activation of PKA associated with the rapid increase in cyclic AMP content.


Assuntos
AMP Cíclico/biossíntese , Lipase Lipoproteica/metabolismo , 1-Metil-3-Isobutilxantina/farmacologia , Animais , Carcinoma de Ehrlich/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Sulfato de Dextrana/farmacologia , Masculino , Camundongos , Propranolol/farmacologia
19.
Int J Oncol ; 12(6): 1355-9, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9592199

RESUMO

Silica and related substances such as silicate have been proven to possess "adjuvant effects". We have previously reported a finding of polyclonal human T cell activation induced by silicate as a superantigen in vitro. In this study, we observed activation-induced cell death in human lymphocytes after stimulation with chrysotile, a kind of silicate. Apoptotic cells were detected flow cytometrically using the TUNEL assay, and the maximum appearance of TUNEL positive cells occurred on day 4 of incubation. Simultaneously the manifestation of small-sized cells in the specimens increased implying apoptosis. Fas expression on lymphocytes increased to day 3 of incubation with chrysotile, and then spontaneously decreased on day 4 when remarkable apoptosis could be detected. Based on these results it is conceivable that activation-induced cell death occurred through Fas-Fas ligand interaction in lymphocytes after stimulation with silicate in a concentration with which no acute cytotoxicity has been detected. Whether and how the repeated apoptosis in definite clones of lymphocytes causes the induction of sFas synthesis need clarification.


Assuntos
Silicatos/farmacologia , Linfócitos T/imunologia , Asbestos Serpentinas/farmacologia , Complexo CD3/biossíntese , Complexo CD3/efeitos dos fármacos , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/fisiologia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/fisiologia , Carcinógenos/administração & dosagem , Carcinógenos/farmacologia , Morte Celular/efeitos dos fármacos , Proteína Ligante Fas , Humanos , Receptores de Lipopolissacarídeos/biossíntese , Receptores de Lipopolissacarídeos/efeitos dos fármacos , Ativação Linfocitária/efeitos dos fármacos , Glicoproteínas de Membrana/biossíntese , Glicoproteínas de Membrana/efeitos dos fármacos , Silicatos/administração & dosagem , Silicatos/imunologia , Superantígenos/farmacologia , Linfócitos T/citologia , Linfócitos T/fisiologia
20.
Immunobiology ; 204(4): 458-65, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11776400

RESUMO

Autoantibodies against DNA topoisomerase I (anti-topo I) have been reported to be specific to systemic sclerosis (SSc), however, anti-topo I was detected in patients with silicone breast implants, SLE without features of SSc, and rheumatic diseases. We detected anti-topo I positive silicosis patients without any symptoms of autoimmune diseases. The correlation between anti-topo I autoantibody responses and HLA class II has been established. HLA-DRB1*1502; DQB1*0601 has been reported to be the most frequent anti-topo I associated haplotype among Japanese SSc patients. In this study, haplotype HLA-DR15; DQ6 was detected in all 4 anti-topo I positive Asian Japanese SSc patients randomly selected. Furthermore, HLA-DQB1*0402 was identified in 3 of 4 anti-topo I positive silicosis patients. These findings coincide with the results of a previous study, in which all 4 Japanese patients with anti-topo I had the DQB1*04 alleles, whereas no studies among Caucasian-Americans, African-Americans and Choctaw Indians found the involvement of DQB1*04. We investigated common features among various DQB 1 alleles. HLA-DQB I with a distinct characteristic is clearly involved in the anti-topo I response irrespective of ethnic groups, the main disease, or silica exposure. A common positioning of distinct amino acids, (i.e. positions 14, 30, 57 and 77 of the DQbeta1 domain are methionine, tyrosine, aspartic acid and threonine, respectively,) seems to be associated with anti-topo I response. The above-mentioned amino acid sequence is detected in alleles *0301, *0303, *0306, *0401, *0402, *0601 and *0602.


Assuntos
Alelos , Autoanticorpos/imunologia , DNA Topoisomerases Tipo I/imunologia , Genes MHC da Classe II , Antígenos HLA-DQ/genética , Escleroderma Sistêmico/genética , Silicose/genética , Sequência de Aminoácidos , Aminoácidos , Antígenos HLA-DP/genética , Antígenos HLA-DP/imunologia , Cadeias beta de HLA-DP , Antígenos HLA-DQ/imunologia , Cadeias beta de HLA-DQ , Antígenos HLA-DR/genética , Antígenos HLA-DR/imunologia , Cadeias HLA-DRB1 , Humanos , Dados de Sequência Molecular , Estrutura Terciária de Proteína , Escleroderma Sistêmico/imunologia , Silicose/imunologia , Células Tumorais Cultivadas
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