RESUMO
The cyclin-dependent kinase (CDK) inhibitor p27 binds and inhibits the kinase activity of several CDKs. Here we report an analysis of the behavior and partners of p27 in Swiss 3T3 mouse fibroblasts during normal mitotic cell cycle progression, as well as in cells arrested at different stages in the cycle by growth factor deprivation, lovastatin treatment, or ultraviolet (UV) irradiation. We found that the level of p27 is elevated in cells arrested in G0 by growth factor deprivation or contact inhibition. In G0, p27 was predominantly monomeric, although some portion was associated with residual cyclin A.Cdk2. During G1, all of p27 was associated with cyclin D1.Cdk4 and was then redistributed to cyclin A.Cdk2 as cells entered S phase. The loss of the monomeric p27 pool as cyclins accumulate in G1 is consistent with the in vivo and in vitro data showing that p27 binds better to cyclin.CDK complexes than to monomeric CDKs. In growing cells, the majority of p27 was associated with cyclin D1 and the level of p27 was significantly lower than the level of cyclin D1. In cells arrested in G1 with lovastatin, cyclin D1 was degraded and p27 was redistributed to cyclin A.Cdk2. In contrast to p21 (which is a p27-related CDK inhibitor and is induced by UV irradiation), the level of p27 was reduced after UV irradiation, but because cyclin D1 was degraded more rapidly than p27, there was a transient increase in binding of p27 to cyclin A.Cdk2. These data suggest that cyclin D1.Cdk4 acts as a reservoir for p27, and p27 is redistributed from cyclin D1.Cdk4 to cyclin A.Cdk2 complexes during S phase, or when cells are arrested by growth factor deprivation, lovastatin treatment, or UV irradiation. It is likely that a similar principle of redistribution of p27 is used by the cell in other instances of cell cycle arrest.
Assuntos
Células 3T3/citologia , Proteínas de Ciclo Celular , Quinases Ciclina-Dependentes/antagonistas & inibidores , Lovastatina/farmacologia , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas Supressoras de Tumor , Raios Ultravioleta , Células 3T3/efeitos dos fármacos , Células 3T3/metabolismo , Células 3T3/efeitos da radiação , Animais , Sequência de Bases , Compartimento Celular , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/efeitos da radiação , Ciclina D1 , Inibidor de Quinase Dependente de Ciclina p27 , Ciclinas/metabolismo , Interfase/efeitos dos fármacos , Camundongos , Mitose , Dados de Sequência Molecular , Nocodazol/farmacologia , Proteínas Oncogênicas/metabolismoRESUMO
Cross-linking surface immunoglobulin (Ig)M on the WEHI-231 B-cell lymphoma results in decreased cell size, G1/S growth arrest, and finally DNA cleavage into oligonucleosomal fragments that are the classical features of apoptotic cells. Treatment of WEHI-231 cells with anti-IgM in early G1 phase prevents phosphorylation of the retinoblastoma gene product (pRb) and inhibits entry into S phase. Using unsynchronized cells, we previously demonstrated that cyclin A-associated and Cdk2-dependent GST-pRb kinase activity were inhibited in WEHI-231 cells treated with anti-IgM. We now show that progression of elutriated early G1 phase WEHI-231 cells from early into late G1 phase is accompanied by an increase in the abundance of cyclin A protein and cyclin A-associated kinase activity. Treatment of early G1 cells with anti-IgM prevented this increase in cyclin A-associated kinase activity at late G1, despite minimal changes in the overall level of cyclin A and Cdk2 proteins. Late G1 cells, which already possess high cyclin A-associated kinase activity, were insensitive to anti-IgM treatment and were able to complete the cell cycle. We also found that anti-IgM-treated cells contained increased amounts of the Cdk inhibitor protein p27Kip1. Essentially all of the cyclin A in treated cells was associated with p27, a result which we propose explains the lack of cyclin A/Cdk2 kinase activity. Accumulation of p27 in cyclin A kinase complexes, however, did not decrease the amount of Cdk2 bound to cyclin A. Thus, cross-linking IgM on growth-inhibitable B-cell lymphomas affects cyclin A kinase activity by increasing the levels of p27 in this complex, thus preventing productive pRb phosphorylation and leading to cell cycle arrest and subsequent apoptosis. These results are discussed in terms of the cell cycle restriction points that regulate lymphocyte function, as well as the lineage-specific differences in cell cycle control.
Assuntos
Anticorpos Anti-Idiotípicos/imunologia , Linfócitos B/citologia , Quinases relacionadas a CDC2 e CDC28 , Proteínas de Ciclo Celular , Quinases Ciclina-Dependentes/antagonistas & inibidores , Ciclinas/fisiologia , Proteínas Associadas aos Microtúbulos/fisiologia , Proteínas Proto-Oncogênicas , Proteínas Supressoras de Tumor , Animais , Linfócitos B/imunologia , Western Blotting , Diferenciação Celular/fisiologia , Linhagem Celular , Quinase 2 Dependente de Ciclina , Quinase 4 Dependente de Ciclina , Inibidor de Quinase Dependente de Ciclina p27 , Quinases Ciclina-Dependentes/biossíntese , Quinases Ciclina-Dependentes/metabolismo , Inibidores Enzimáticos/metabolismo , Fase G1 , Genes Supressores de Tumor , Linfoma de Células B , Camundongos , Fosforilação , Proteínas Serina-Treonina Quinases/biossíntese , Proteína do Retinoblastoma/metabolismo , Células Tumorais CultivadasRESUMO
OBJECTIVE: This study aims to investigate the association of long-term weight-change slopes, weight fluctuation and the risk of type 2 diabetes mellitus (T2DM) in middle-aged Japanese men and women. METHODS: A total of 4234 participants of Aichi Workers' Cohort Study who were aged 35-66 years and free of diabetes in 2002 were followed through 2014. Past body weights at the ages of 20, 25, 30, 40 years, and 5 years before baseline as well as measured body weight at baseline were regressed on the ages. Slope and root-mean-square-error of the regression line were obtained and used to represent the weight changes and the weight fluctuation, respectively. The associations of the weight-change slopes and the weight fluctuation with incident T2DM were estimated by Cox proportional hazards models. RESULTS: During the median follow-up of 12.2 years, 400 incident cases of T2DM were documented. After adjustment for baseline overweight and other lifestyle covariates, the weight-change slopes were significantly associated with higher incidence of T2DM (hazard ratio (HR): 1.80, 95% confident interval (CI): 1.17-2.77 for men; and HR: 2.78, 95% CI: 1.07-7.23 for women), while the weight fluctuation was not (HR: 1.08, 95% CI: 1.00-1.18 for men and HR: 1.02, 95% CI: 0.84-1.25 for women). CONCLUSIONS: Regardless of the presence of overweight, the long-term weight-change slopes were significantly associated with the increased risk of T2DM; however, the weight fluctuation was not associated with the risk of T2DM in middle-aged Japanese men and women.
Assuntos
Peso Corporal/fisiologia , Diabetes Mellitus Tipo 2/epidemiologia , Estilo de Vida , Sobrepeso/epidemiologia , Adulto , Idoso , Estudos de Coortes , Diabetes Mellitus Tipo 2/fisiopatologia , Feminino , Humanos , Incidência , Japão , Masculino , Pessoa de Meia-Idade , Sobrepeso/fisiopatologia , Fatores de RiscoRESUMO
Human retroviruses, human T cell leukemia viruses (HTLV) and human immunodeficiency viruses (HIV), express two classes of mRNAs; fully spliced mRNA in the early phase and intron-containing mRNA in a later phase. The expressions of HTLV-1 rex and HIV rev by early mRNAs are essential for the later phase of expression of intron-containing gag and env mRNAs. Each two cis-acting sequences seem to be involved in these regulations: HTLV-1 rex depends on a splice donor (SD) and a responsible element (RXE) at the 3' end, whereas HIV rev depends on a specific repressive sequence (CRS) and a responsible element (RRE) in the intron, but does not require an SD. For analyses of these cis-acting sequences, we inserted an HIV element RRE into an HTLV-1 construct and tested the responses to HTLV-1 rex and HIV rev regulations. The results indicated that both rex and rev could regulate RNA expression of these chimeric constructs responding to an HIV RRE. A repressive element (CRS) was dispensable, and the intronic or exonic location of RRE was not important. These observations suggest that rex and rev could be functionally equivalent to induce cytoplasmic expression of unspliced RNA which expression is suppressed either by an SD or CRS depending on the construction.
Assuntos
Expressão Gênica , Genes Virais , HIV-1/genética , Vírus Linfotrópico T Tipo 1 Humano/genética , Splicing de RNA , RNA Mensageiro/genética , Linhagem Celular , Produtos do Gene gag/genética , Humanos , Íntrons , Plasmídeos , RNA Viral/genética , Transfecção , Proteínas do Envelope Viral/genéticaRESUMO
The Rex protein of human T-cell leukemia viruses (HTLV) is a trans-acting regulator inducing the expression of gag and env mRNA containing the introns. The rex gene can also induce expression of unspliced RNA of human immunodeficiency viruses (HIV). We have analyzed the level of spliced and unspliced RNAs in nucleus and cytoplasm to understand the mechanism by which the Rex protein modulates RNA processing. With the gag gene of HTLV-1, the unspliced RNA was accumulated by Rex protein in both nucleus and cytoplasm. However, the apparent effects on nuclear unspliced RNA depended on the reporter genes: with the env gene of HTLV-1 as well as that of HIV-1, Rex did not accumulate the unspliced RNA in nucleus, but did so only in cytoplasm. These results clearly indicate that Rex protein not only activates the nuclear export of unspliced RNA, but also modulates some steps of RNA processing before the splicing, probably through stabilization of the precursor RNA.
Assuntos
Núcleo Celular/metabolismo , Citoplasma/metabolismo , Regulação Viral da Expressão Gênica/genética , Produtos do Gene env/metabolismo , Produtos do Gene rex/fisiologia , Genes pX/fisiologia , RNA Viral/metabolismo , Humanos , TransfecçãoRESUMO
Leukocyte tyrosine kinase (ltk) is a receptor-type tyrosine kinase which is suggested to be expressed in hematopoietic cells and neuronal cells in human. Recently we have cloned a full sized human ltk cDNA which has a 423 amino acid extracellular domain which may bind to unknown ligand(s), and a 415 amino acid cytoplasmic domain which contains a tyrosine kinase domain. To identify the cellular signal transducer proteins binding to the ltk protein, we have analysed the recombinant ltk protein transiently expressed in COS cells. By an in vitro immune complex kinase assay, a major 140 kDa phosphoprotein and other cellular phosphoproteins were co-immunoprecipitated with the 100 kDa ltk protein using anti-ltk monoclonal antibodies. Western blot analysis revealed that the wild-type ltk protein was tyrosine-phosphorylated in vivo and associated with SH2 containing proteins, PLC-gamma 1, p85 subunit of PI3-K and GAP, in vivo. Furthermore, the wild-type ltk protein also binds to a serine/threonine kinase, Raf-1, in vivo. In contrast, none of these signal transducer proteins were associated with a kinase-negative ltk mutant (K544M-ltk) in which methionine at the putative ATP binding site was replaced with lysine. These results suggest that the associations of the ltk protein with those signaling molecules depend on the tyrosine kinase activity of the ltk protein. This is the first detection of cytoplasmic signal transducers that bind to the ltk protein in vivo.
Assuntos
Isoenzimas/metabolismo , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Receptores Proteína Tirosina Quinases/metabolismo , Fosfolipases Tipo C/metabolismo , Sequência de Bases , Linhagem Celular , Primers do DNA , Proteínas Ativadoras de GTPase , Humanos , Dados de Sequência Molecular , Fosfatidilinositol 3-Quinases , Fosfolipase C gama , Fosforilação , Proteínas Proto-Oncogênicas c-raf , Receptores Imunológicos/metabolismo , Especificidade por Substrato , Tirosina/metabolismoRESUMO
We have isolated the mouse c-crk cDNA from a mouse liver cDNA library. It encodes 304 amino acids and consists mainly of SH2/SH3 regions. In Northern blot analysis, the mouse c-crk mRNA is expressed ubiquitously in every tissue and organ, suggesting that the c-Crk protein may be a common signal transducing molecule among tissues. In contrast to the v-Crk protein, which has a single SH3 domain, the c-Crk protein contains two, the more N-terminal SH3(1) domain and the C-terminal SH3(2) domain. To elucidate functions of these SH3 domains, we have constructed two c-crk mutants, B-crk and D-crk, which lack the SH3(2) and the SH3(1) domain, respectively. These mutants were expressed in rat 3Y1 cells, and examined for their transforming ability in terms of morphological phenotypes and for tyrosine phosphorylation profiles of cells expressing the mutant proteins. Morphological alteration and increased tyrosine phosphorylation of 130-140 kDa proteins, the major component of which is the Crk-associated p130, were observed in cells expressing B-Crk as well as those expressing v-Crk, but little in cells expressing c-Crk even at a similar level of expression. Although a highly tyrosine-phosphorylated form of the p130 was coimmunoprecipitated with c-Crk as well as B-Crk, the relative level of tyrosine phosphorylation of the p130, which is normalized to the amount of Crk protein immunoprecipitated, was 10 to 20 times higher in B-Crk-expressing cells than in c-Crk- or D-Crk-expressing cells. The present results indicate that the SH3(2) domain of mouse c-Crk protein negatively regulates tyrosine phosphorylation of the p130, and that lack of the SH3(2) domain in B-Crk and v-Crk may contribute, at least partly, to their morphological alteration or transforming ability through increasing tyrosine phosphorylation of the p130.
Assuntos
Proteínas Tirosina Quinases/fisiologia , Proteínas Proto-Oncogênicas/fisiologia , Tirosina/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Células Cultivadas , DNA Complementar/química , DNA Complementar/isolamento & purificação , Fibroblastos/metabolismo , Humanos , Camundongos , Dados de Sequência Molecular , Fosforilação , Proteínas Proto-Oncogênicas/química , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas c-crk , Ratos , Relação Estrutura-Atividade , TransfecçãoRESUMO
Human cDNA clones encoding four novel putative transmembrane protein serine/threonine kinases, denoted activin receptor-like kinase (ALK) -1, -2, -3 and -4, were obtained using a polymerase chain reaction (PCR)-based strategy. The PCR primers were designed based upon the sequence similarity between the activin receptor type II and Daf-1. The cDNA clones for ALK-1, -2 and -3 encode complete proteins of 503, 509 and 532 amino acids respectively. The ALK-4 cDNA is incomplete and the predicted protein of 383 amino acids has a truncated extracellular domain. The ALKs share similar domain structures, comprising predicted signal sequences at the N-terminals, followed by hydrophilic cysteine-rich ligand-binding domains, single hydrophobic transmembrane regions and C-terminal intracellular portions that consist almost entirely of putative serine/threonine kinase domains. The ALKs have approximately 40% sequence identity to activin receptors type II and IIB, transforming growth factor-beta (TGF-beta) type II receptor and Daf-1 in the kinase domains. However, the sequence identities are higher (60-79%) between ALK-1, -2, -3 and -4, suggesting that they form a subfamily among the putative receptor serine/threonine kinases. The extracellular domains of ALKs show only little sequence identity to other putative receptor serine/threonine kinases, but the cysteine residues are conserved. Their structural properties suggest that ALK-1 to -4 are receptors that may bind ligands that are members of the TGF-beta superfamily. The expression of mRNA in human tissues varied for the different ALKs; ALK-2 and ALK-4 showed ubiquitous tissue expression patterns, whereas the distribution of ALK-1 and ALK-3 varied strongly between different tissues with more restricted expression patterns. These results suggest that each ALK may have different in vivo functions.
Assuntos
Proteínas Serina-Treonina Quinases/isolamento & purificação , Receptores de Superfície Celular/isolamento & purificação , Receptores de Ativinas , Sequência de Aminoácidos , Sequência de Bases , Receptores de Proteínas Morfogenéticas Ósseas Tipo I , Códon/química , Códon/genética , Humanos , Dados de Sequência Molecular , Fases de Leitura Aberta , Proteínas Serina-Treonina Quinases/genética , RNA Mensageiro/genética , RNA Mensageiro/isolamento & purificação , Receptores de Superfície Celular/genética , Análise de Sequência de DNARESUMO
This experiment was undertaken to explore a novel method of therapy for insulin-dependent diabetes mellitus (IDDM), using nonobese diabetic (NOD) mice that had symptoms and histologic changes similar to those of human IDDM patients. We examined preventive and therapeutic effects of large-dose nicotinamide administration on diabetes in NOD mice. Eighteen young female NOD mice without glycosuria were randomly divided into two groups; nine received subcutaneous nicotinamide (0.5 mg/g body wt) injections every day and the other nine were maintained as a control group and not injected. After 40 days, all of the mice given nicotinamide showed almost normal glucose tolerance and only mild insulitis on histologic study. On the other hand, marked glycosuria and severe insulitis were observed in six of the nine mice not injected. Four of six NOD mice given nicotinamide from the day of the first occurrence of marked glycosuria displayed a disappearance of glycosuria and an improvement in glucose tolerance during the therapy; however, urine sugar became negative in only one of six mice that received nicotinamide from 1 to 2 wk after the onset of marked glycosuria. These results indicate that nicotinamide has preventive and therapeutic effects on diabetes in NOD mice, and suggest the reversibility of B-cell damage, at least at a very early stage of IDDM.
Assuntos
Diabetes Mellitus Experimental/prevenção & controle , Ilhotas Pancreáticas/patologia , Niacinamida/administração & dosagem , Animais , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/tratamento farmacológico , Modelos Animais de Doenças , Feminino , Teste de Tolerância a Glucose , Injeções Subcutâneas , Ilhotas Pancreáticas/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos , Niacinamida/farmacologiaRESUMO
We attempted to evaluate familial aggregation and coaggregation of history of hypertension and stroke. Past and family history of hypertension and stroke for 83 089 probands and their relatives were obtained from a data set for the Japan Collaborative Cohort Study for Evaluation of Cancer Risk sponsored by the Ministry of Education (JACC Study), which was initiated from 1988 to 1990. First, evaluation was performed for familial aggregation of each of two disorders using ordinal logistic regression of the generalized estimation equations (GEE) to account for dependence of observations within families. Secondly, in order to evaluate the familial congregation of the history of hypertension and stroke, a GEE-based multivariate probed predictive model was applied. After adjusting for the proband's age, level of obesity, smoking status, drinking status, habitation area, and the gender and type of the relatives, the estimated odds ratios for the intraindividual clustering and familial aggregation of the disease history showed statistically significant relationships. In addition, the history of the two disorders showed a significant relationship in terms of familial coaggregation independently of the aggregation of each disorder itself. Our results confirmed that hypertension and stroke coaggregate strongly within families through possible effects of genetic factors, which, alone or in conjunction with environmental factors, influence susceptibility to both hypertension and stroke.
Assuntos
Hipertensão/complicações , Hipertensão/genética , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/genética , Adulto , Idoso , Estudos de Coortes , Coleta de Dados , Feminino , Predisposição Genética para Doença , Humanos , Hipertensão/epidemiologia , Japão/epidemiologia , Modelos Logísticos , Masculino , Anamnese , Pessoa de Meia-Idade , Razão de Chances , Acidente Vascular Cerebral/epidemiologiaRESUMO
When determining the concentration of a particular protein in a cell extract, or when comparing the amount of a protein in different samples, it is a common practice to use specific antibodies in immunoblotting to compare the samples side by side with known amounts of purified protein. Here we show that with many antibodies, in particular monoclonal antibodies, the sensitivity of detecting the cognate antigen on immunoblots can be significantly reduced when the antigen is in a mixture with other cellular proteins. The signals on the immunoblots are masked by other endogenous proteins in the cell lysate, making the amount of the protein on the immunoblot appear to be less than the actual amount, thus invalidating direct comparison with purified protein.
Assuntos
Western Blotting/métodos , Ciclinas/análise , Células 3T3 , Animais , Anticorpos Monoclonais , Reações Antígeno-Anticorpo , Camundongos , Peso Molecular , Testes de PrecipitinaRESUMO
To study the effect of ventricular hypertrophy on conduction velocity of the activation front noninvasively, transmural conduction indexes were obtained from findings of echocardiography and body surface potential mapping performed in 40 patients with right bundle branch block uncomplicated by the left anterior fascicular block. Because in these patients, left ventricular activation proceeds radially without being modified by right ventricular activation, the index was obtained by dividing ventricular septal thickness measured from the echocardiogram by transmural conduction time, which was taken as the time interval from the onset of the QRS complex to the time when the left ventricular epicardial breakthrough minimum appeared on the potential map. The indexes, ranging from 11 to 45 cm/s, has a good positive linear correlation with the septal thickness (Y = 2.37X - 1.33, correlation coefficient [r] = 0.83) and were abnormally small in some failed hearts. Further, both the mean ventricular activation times in lead V5 and the mean value for total duration of left ventricular activation did not differ significantly in patients with and without left ventricular hypertrophy. These findings suggest that conduction velocity was increased in the hypertrophied ventricle and decreased in the failed hearts. Because there were no significant differences in the mean serum sodium and potassium concentrations in the patients with and without left ventricular hypertrophy, it is concluded that hypertrophy itself most likely caused greater conduction velocity. Enlarged cells and multiple intercalated discs abundant in hypertrophied ventricle would have facilitated intercellular current flow and, hence, conduction velocity and impaired cellular connection in the failed heart would have reduced them. Thus, the transmural conduction index is suggested to be an important aid in interpreting electrocardiograms as well as in estimating the pathologic state of the heart.
Assuntos
Cardiomegalia/diagnóstico , Sistema de Condução Cardíaco/fisiopatologia , Adolescente , Adulto , Idoso , Bloqueio de Ramo/fisiopatologia , Cardiomegalia/fisiopatologia , Ecocardiografia , Eletrocardiografia , Eletrofisiologia , Feminino , Insuficiência Cardíaca/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Contração MiocárdicaRESUMO
1 Characteristics of cyclic GMP- and cyclic AMP-mediated relaxation in aortic segments of rats with chronic heart failure (CHF) and the effects of chronic treatment with an angiotensin I converting enzyme (ACE) inhibitor, trandolapril, were examined 8 weeks after coronary artery ligation. 2 Cardiac output indices of coronary artery-ligated and sham-operated rats were 125+/-8 and 189+/-10 ml min(-1) kg(-1), respectively (P<0.05), indicating the development of CHF at this period. 3 The maximal relaxant response of aortic segments to 10 microM acetylcholine in rats with CHF and sham-operated rats was 64.0+/-5.7 and 86.9+/-1.9%, respectively (P<0.05), whereas the relaxant response to sodium nitroprusside (SNP) remained unchanged. Tissue cyclic GMP content in rats with CHF was lower than that of sham-operated rats. 4 In endothelium-intact segments of rats with CHF, the maximal relaxant response to 10 microM isoprenaline (44.5+/-6.7%) was lower that sham-operated rats (81.3+/-2.5%, P<0.05) and the concentration-response curve for NKH477, a water-soluble forskolin, was shifted to the right without a reduction in the maximal response. Isoprenaline-induced relaxation of aortic segments was attenuated by NG-nitro-L-arginine methyl ester (L-NAME) in sham-operated rats, but not in rats with CHF. Relaxation to 30 microM dibutyryl cyclic AMP in rats with CHF (26.8+/-2.7%) was lower than that in sham-operated rats (63.4+/-11.8%, P<0.05). 5 Trandolapril (3 mg kg(-1) day(-1)) was orally administered from the 2nd to 8th week after the operation. Aortic blood flow of rats with CHF (38.5+/-3.6 ml min(-1)) was lower than that of sham-operated rats (55.0+/-3.0 ml min(-1)), and this reduction was reversed (54.1+/-3.4 ml min(-1)) by treatment with trandolapril. The diminished responsiveness described above was normalized in the trandolapril-treated rat with CHF (i.e., the maximal relaxation to acetylcholine, 94.7+/-1.0%; that to isoprenaline, 80.5+/-2.8%; that to dibutyryl cyclic AMP, 54.7+/-6.2%). However, aortic segments of trandolapril-treated rats with CHF, L-NAME did not attenuate isoprenaline-induced relaxation and the tissue cyclic GMP level was not fully restored, suggesting that the ability of the endothelium to produce NO was still partially damaged. 6 The results suggest that vasorelaxation in CHF, diminished mainly due to dysfunction in endothelial nitric oxide (NO) production and cyclic AMP-mediated signal transduction, was partially restored by long-term treatment with trandolapril. The mechanism underlying the restoration may be attributed in part to prevention of CHF-induced endothelial dysfunction.
Assuntos
Inibidores da Enzima Conversora de Angiotensina/farmacologia , Anti-Hipertensivos/farmacologia , Baixo Débito Cardíaco/tratamento farmacológico , Baixo Débito Cardíaco/fisiopatologia , AMP Cíclico/fisiologia , GMP Cíclico/fisiologia , Indóis/farmacologia , Relaxamento Muscular/efeitos dos fármacos , Músculo Liso Vascular/efeitos dos fármacos , Acetilcolina/farmacologia , Agonistas Adrenérgicos beta/farmacologia , Animais , Aorta/efeitos dos fármacos , Aorta/fisiologia , Colforsina/análogos & derivados , Colforsina/farmacologia , AMP Cíclico/metabolismo , GMP Cíclico/metabolismo , Hemodinâmica/efeitos dos fármacos , Isoproterenol/farmacologia , Masculino , Relaxamento Muscular/fisiologia , Músculo Liso Vascular/fisiologia , Nitroprussiato/farmacologia , Ratos , Ratos Wistar , Vasodilatadores/farmacologiaRESUMO
PURPOSE: We investigated familial aggregation as well as familial covariation of diseases by means of a questionnaire survey dealing with family histories of stomach cancer, stroke, hypertension, diabetes and tuberculosis as well as life style among 2,769 inhabitants of a rural community (84% of census population). METHODS: The strength of familial aggregation was shown by an odds ratio (OR) that compared the number of families in which siblings suffered from one of the above diseases among families in which at least one parent suffered from it, and among families in which neither did. Probands were divided into two groups for analysis: an under-55 "young group," and a 55-and-older "old group." RESULTS: The OR for stomach cancer was lowest and insignificant in the young group, and significant (2.2, p < 0.05) only in the old group. The OR for stroke, hypertension, and tuberculosis was 4.5-5.1 (p < 0.05) in the young group but decreased to 2.3-3.2 in the old group. Diabetes increased from 3.9 to 5.7 (p < 0.05) with advancing age. Age-related OR trends were not affected by exposure to cigarette smoke in the past. Stomach cancer showed a borderline familial covariation with diabetes and a borderline inverse covariation with hypertension. Hypertension showed a familial covariation with stroke and diabetes. CONCLUSIONS: Among the investigated diseases, familial aggregation was weakest for stomach cancer. The results suggest that stomach cancer may share a common familial etiologic factor with diabetes and hypotension.
Assuntos
Neoplasias Gástricas/epidemiologia , Neoplasias Gástricas/genética , Adulto , Distribuição por Idade , Idoso , Transtornos Cerebrovasculares/complicações , Transtornos Cerebrovasculares/epidemiologia , Estudos de Coortes , Comorbidade , Intervalos de Confiança , Complicações do Diabetes , Diabetes Mellitus/epidemiologia , Suscetibilidade a Doenças , Feminino , Humanos , Hipertensão/complicações , Hipertensão/epidemiologia , Incidência , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade , Razão de Chances , Linhagem , Fatores de Risco , População Rural , Distribuição por Sexo , Inquéritos e QuestionáriosRESUMO
An unusual case of renal amyloidosis associated with extensive crescents is reported. Light and electron microscopic examination revealed that deposits of amyloid were almost invariably involved in the locations in which proliferations of epithelial cells in the capsular spaces had merged with the glomerular tufts. Gaps or fractures of the capillary walls were present at such sites, in which amyloid fibrils were mingled with thrombic material containing fibrin. It is highly conceivable that the gaps apparently induced by amyloid deposition, with leakage of fibrin-fibrinogen into the capsular space, play a crucial role in the development of the extracapillary proliferation.
Assuntos
Amiloidose/patologia , Nefropatias/patologia , Idoso , Artrite Reumatoide/complicações , Sedimentação Sanguínea , Capilares/ultraestrutura , Úlcera Duodenal/complicações , Feminino , Febre/etiologia , Hematemese/complicações , Humanos , Falência Renal Crônica/complicações , Glomérulos Renais/patologia , Sangue Oculto , Parotidite/complicaçõesRESUMO
Review of the kidneys from 23 cases of Wegener's granulomatosis revealed necrosis of the renal papillae in five (21.7 per cent). These cases took a fulminant course of the disease consistent with the classic description of Wegener's granulomatosis, prevalence in the older age group, and rapid deterioration of renal function. Morphologic examination of the kidneys uniformly disclosed a variety of lesions in the blood vessels supplying the renal papilla. The most conspicuous was the widely distributed glomerular lesion represented by thrombotic and necrotic occlusion of capillary loops and crescent formation. A medullary interstitial lesion characterized by fibrinoid necrosis of the vasa recta was invariably found in the outer portion of the necrotic papilla. In addition, acute segmental and diffuse necrosis and occlusion by thrombosis were identified in the branches of spiral arteries in the adjoining papilla. The results provide an anatomic basis for the assumption that papillary ischemia due to impairment of the dual blood supply from the vasa recta and the calyceal arteries is the essential factor in papillary necrosis.
Assuntos
Granulomatose com Poliangiite/complicações , Necrose Papilar Renal/etiologia , Adolescente , Adulto , Feminino , Glomerulonefrite/etiologia , Glomerulonefrite/patologia , Granulomatose com Poliangiite/patologia , Humanos , Medula Renal/patologia , Necrose Papilar Renal/patologia , Masculino , Pessoa de Meia-Idade , Nefrite Intersticial/etiologia , Nefrite Intersticial/patologia , Artéria Renal/patologia , Vasculite/complicações , Vasculite/patologiaRESUMO
Of 1070 patients with gastric cancers, 292 patients underwent total gastrectomy during 13 years. Sixty patients were more than 70 years of age and 232 were under 69 years. The incidence of well-differentiated carcinomas and poorly differentiated carcinomas was the same in the elderly patients, whereas the latter was dominant in the young patients. However, there was no significant difference between the two groups regarding location, size, macroscopic patterns, extent of lymph metastases, or stage classification. The rates of preoperative surgical risk factors were significantly different between the two groups (p less than 0.01): 90.0% for the elderly and 34.9% for the young patients. However, the rates of postoperative morbidity and mortality were 31.7% and 3.3% for the elderly and 24.1% and 1.3% for the young patients, respectively, with no significant difference. The 5- and 10-year survival rates after curative total gastrectomy were 48.6% and 23.2% for the elderly compared with 49.4% and 33.6% for the young patients, respectively, with no significant difference. A 5-year survival rate after noncurative operation was 0% for the elderly and 6.4% for the young patients. These results indicate that, when performed for cure, total gastrectomy with systematic lymphadenectomy can provide good long-term results for elderly, as well as young, patients.
Assuntos
Gastrectomia , Neoplasias Gástricas/cirurgia , Fatores Etários , Idoso , Humanos , Excisão de Linfonodo , Metástase Linfática , Morbidade , Mortalidade , Metástase Neoplásica , Estadiamento de Neoplasias , Estudos Retrospectivos , Neoplasias Gástricas/patologiaRESUMO
BACKGROUND: Mass screening for gastric cancer has been established in Japan, and asymptomatic submucosal tumors are often detected. This retrospective study was made to evaluate the proper surgical management of malignant submucosal tumors of the stomach. METHODS: One hundred submucosal tumors of the stomach were surgically resected, irrespective of symptoms and size. Up to 45% of these tumors, including 44 myogenic lesions, 23 non-Hodgkin's lymphomas, and 11 schwannomas, proved malignant. Myogenic sarcomas were classified in low and high grades according to mitotic rates, cellularity, and pleomorphism. RESULTS: Thirty-five of 55 benign tumors and four of nine low-grade sarcomas underwent enucleation only, without recurrence. The remaining five low-grade and 11 high-grade sarcomas were treated by radical gastrectomy; the 5-year survival was 100% for the former and 80% for the latter. Eighteen patients with lymphomas underwent total or subtotal gastrectomy, and three patients underwent noncurative resection; the 5-year survival rates were 54.2% and 0%, respectively, with a clear significant difference (p < 0.001). Adjuvant chemotherapy was significantly superior to surgery alone (p < 0.05). Other factors did not affect survival of lymphoma. CONCLUSIONS: With these observations, we believe that following the patients with submucosal tumor without surgery is not reasonable. Enucleation will suffice for low-grade sarcomas and benign tumors; high-grade sarcomas can be well treated by gastrectomy. Total or subtotal gastrectomy with systematic lymph node dissection when performed for cure can provide good results for resectable lymphomas.
Assuntos
Neoplasias Gástricas/cirurgia , Adulto , Idoso , Feminino , Gastrectomia , Humanos , Leiomioma/cirurgia , Leiomiossarcoma/cirurgia , Linfoma não Hodgkin/cirurgia , Masculino , Pessoa de Meia-Idade , Neurilemoma/cirurgia , Estudos Retrospectivos , Sarcoma/cirurgia , Neoplasias Gástricas/mortalidade , Taxa de SobrevidaRESUMO
We report a case with typical clinical features of acute promyelocytic leukemia (APL) carrying an atypical chromosomal aberration involving chromosomes 15, 17, and 18. Molecular analysis using Southern blot hybridization and reverse transcriptase-polymerase chain reaction (RT-PCR) proved the creation of the PML/RAR alpha fusion gene in this case. These findings support the notion that this fusion is of crucial importance to leukemogenesis of APL.
Assuntos
Cromossomos Humanos Par 15 , Cromossomos Humanos Par 17 , Cromossomos Humanos Par 18 , Leucemia Promielocítica Aguda/genética , Receptores do Ácido Retinoico/genética , Translocação Genética , Sequência de Bases , Southern Blotting , Humanos , Cariotipagem , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Reação em Cadeia da PolimeraseRESUMO
The purpose of this study was to assess medication compliance and to document side effects among a large number of Japanese patients receiving antihypertensive treatment. A total of 6289 patients being treated for hypertension returned completed questionnaires about their current blood pressure, therapy, side effects, and compliance with physicians' instructions. In addition, 4417 physicians returned completed questionnaires about their prescribing practices, side effects experienced by patients, and patient compliance. The antihypertensive agents they most often prescribed were calcium channel blockers, followed by angiotensin-converting enzyme inhibitors, beta-blockers, and diuretics. The proportion of patients who had well-controlled blood pressure, defined as systolic blood pressure < 160 mm Hg and diastolic blood pressure < 95 mm Hg, was similar regardless of the class of antihypertensive agent prescribed. Forty-nine percent of the patients with well-controlled blood pressure reported having at least one side effect while taking their current antihypertensive therapy, whereas a significantly greater percentage of patients (61%) with poorly controlled blood pressure reported side effects. Patients whose blood pressure was poorly controlled tended to have a higher incidence of most side effects than did those with well-controlled blood pressure. Also, the rate of intentional noncompliance was significantly higher in the group with poorly controlled blood pressure. In addition, the rate of noncompliance increased with the number of side effects reported. Although the causal relationship between side effects and non-compliance cannot be determined from this study, further investigation is warranted to better understand the impact these factors may have on overall cardiovascular morbidity and mortality.