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1.
Phys Chem Chem Phys ; 20(5): 2970-2975, 2018 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-28952630

RESUMO

Novel regioisomeric alkylated-naphthalene liquids were designed and synthesized. In the solvent-free liquid state, 1-alkyloxy regioisomers showed excimeric luminescence, whereas 2-alkyloxy analogues exhibited monomer-rich luminescence features. Correlations among the molecular structures and the photophysical, calorimetric, and rheological properties are presented, demonstrating the impact of regioisomerism on the alkylated-chromophore liquid systems.

2.
J Pathol ; 216(3): 365-74, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18788085

RESUMO

Benzo[a]pyrene diol epoxide (B[a]PDE), the ultimate carcinogenic metabolite of benzo[a] pyrene, has been implicated in the mutagenesis of the p53 gene involved in smoking-associated lung cancer. To further understand the role of B[a]PDE in lung tumour progression, we investigated its effect on the numerical integrity of centrosomes and chromosome stability in lung cancer cells lacking p53. Exposure of p53-deficient H1299 lung cancer cells to B[a]PDE resulted in S-phase arrest, leading to abnormal centrosome amplification. Analysis of H1299 cells stably expressing fluorescence-tagged centrin (a known centriolar marker) revealed that the centrosome amplification was primarily attributable to excessive centrosome duplication rather than to centriole splitting. Forced expression of POLK DNA polymerase, which has the ability to bypass B[a]PDE-guanine lesions in an error-free manner, suppressed the B[a]PDE-induced centrosome amplification. Fluorescence in situ hybridization analyses with probes specific for chromosomes 2, 3, and 16 revealed that B[a]PDE exposure also led to chromosome instability, which was likely to have resulted from centrosome amplification. We extended these findings to primary lung carcinomas containing non-functional p53, and found a strong association between centrosome amplification and a high level of B[a]PDE-DNA accumulation. Therefore B[a]PDE contributes to neoplasia by inducing centrosome amplification and consequent chromosome destabilization as well as its mutagenic activity.


Assuntos
7,8-Di-Hidro-7,8-Di-Hidroxibenzo(a)pireno 9,10-óxido/toxicidade , Centrossomo/ultraestrutura , Instabilidade Cromossômica , Neoplasias Pulmonares/ultraestrutura , Mutagênicos/toxicidade , Proteína Supressora de Tumor p53/deficiência , Idoso , Ciclo Celular/efeitos dos fármacos , Transformação Celular Neoplásica , Distribuição de Qui-Quadrado , Adutos de DNA/análise , DNA Polimerase Dirigida por DNA/metabolismo , Feminino , Citometria de Fluxo , Técnica Indireta de Fluorescência para Anticorpo , Perfilação da Expressão Gênica , Humanos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Masculino , Pessoa de Meia-Idade , Análise de Sequência com Séries de Oligonucleotídeos
3.
Cancer Epidemiol Biomarkers Prev ; 9(7): 675-80, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10919737

RESUMO

Cytochrome P450 2E1 (Cyp2E1) is involved in the metabolic oxidation of carcinogenic nitroso compounds, including N-nitrosoamines. There is an RsaI polymorphism in the transcriptional regulatory region of this gene, and in vitro evidence suggests that the variant type of this polymorphic site has higher transcriptional activity but less chlorzoxazone-metabolizing activity. Interindividual differences in the metabolic capacity of Cyp2E1 are assumed to be associated with cancer susceptibility, but the results of the previous studies on the relation between Cyp2E1 RsaI polymorphism and cancer susceptibility have been inconsistent. Two case-control studies of gastric cancer in Japanese Brazilians (96 cases, 192 controls) and Brazilians not of Japanese ancestry (non-Japanese Brazilians; 236 cases, 236 controls) in São Paulo were designed to clarify the role of the Cyp2E1 RsaI genotype in susceptibility to gastric cancer after considering multifactorial environmental influences. The subjects with variant RsaI genotypes amounted to 47% (28 of 59) and 48% (64 of 133), respectively, of the Japanese cases and controls, and 6% (11 of 187) and 10% (19 of 192), respectively, of the non-Japanese cases and controls. As expected, a difference in the distributions of the two groups was observed. The odds ratio of the RsaI variant genotype of Cyp2E1 was 0.46 (95% confidence interval, 0.21-1.04) in the non-Japanese Brazilian population and 0.98 (95% confidence interval, 0.50-1.90) in the Japanese Brazilian population after adjusting for sex, age, tobacco use, and meat consumption. Additional adjustment for potential confounding factors did not change the odds ratio substantially. No significant interactions were observed between the polymorphism and environmental factors. In regard to the histological type of gastric cancer, the variant genotype was significantly more prevalent than the common genotype in Japanese subjects with diffuse type gastric cancer. Our study suggests that the Cyp2E1 RsaI polymorphism is associated with a reduced risk of gastric cancer, although how the assumed increase in Cyp2E1 expression produced by this polymorphism is related to a reduced risk of cancer remains unclear. The observations in this study are consistent with the recent observations of esophageal cancer in endemic areas of China.


Assuntos
Citocromo P-450 CYP2E1/genética , Predisposição Genética para Doença , Polimorfismo Genético , Neoplasias Gástricas/etnologia , Neoplasias Gástricas/genética , Idoso , Brasil/epidemiologia , Estudos de Casos e Controles , Dieta , Feminino , Genótipo , Humanos , Japão/etnologia , Masculino , Pessoa de Meia-Idade , Medição de Risco
4.
Cancer Epidemiol Biomarkers Prev ; 3(2): 145-8, 1994 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7914125

RESUMO

Mspl restriction fragment length polymorphism in cytochrome P-450 IA1 (CypIA1) gene, which has been associated with lung cancer susceptibility in Japanese, was studied in persons from Rio de Janeiro, in the framework of a hospital-based, age, race (black or nonblack), and gender-matched case-control study (n = 222; 110 cases and 112 controls). Contrary to the hypothesis, there was no difference in the frequency of the C genotype (Mspl site-present homozygous), even after racial breakdown. There were no significant differences between cases and controls when categorized according to tobacco consumption. The lifetime quantity of tobacco smoked was not different among lung cancer patients with three different genotypes (A, Mspl site-absent, homozygous; B, heterozygote; and C). The background frequency of the Mspl polymorphism C genotype is a little less than 10%, similar to that of the Japanese healthy population. The CyplA1 Mspl polymorphism itself does not seem to be related to susceptibility to bronchial carcinogenesis in this area.


Assuntos
Comparação Transcultural , Sistema Enzimático do Citocromo P-450/genética , Neoplasias Pulmonares/genética , Adulto , Idoso , População Negra/genética , Brasil , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma de Células Pequenas/genética , Estudos de Casos e Controles , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Fragmento de Restrição , Fatores de Risco
5.
Artigo em Inglês | MEDLINE | ID: mdl-7534543

RESUMO

Ile-Val polymorphism in exon 7 of cytochrome P450IA1 (CypIA1) and RsaI polymorphism of cytochrome P450IIE1 (CypIIE1) were examined in a case-control study of lung cancer in Rio de Janeiro, Brazil. The Val-containing genotype in exon 7 of CypIA1 was found to be associated with lung cancer in this population (odds ratio, 2.26; 95% confidence interval, 1.14-4.47 for 99 cases versus 108 controls of 123 matched pairs), whereas RsaI polymorphism in CypIIE1 was not associated with lung cancer susceptibility. In squamous cell carcinoma, the degree of association of Val-containing genotype was greater in those with fewer pack-years of smoking. The RsaI polymorphism of CypIIE1 has a different distribution from the Japanese pattern and is not associated with lung cancer. When we analyzed the association of Ile-Val polymorphism to MspI polymorphism of CypIA1, the Val/Val homozygote was found only in the subpopulation with the MspI site-present homozygote. The apparent lack of association of CypIA1 MspI polymorphism with lung cancer in this area reported in our previous study and the results of the present study indicate that the "true" responsible site for lung cancer susceptibility should be the Ile-Val polymorphism in the catalytic site of CypIA1.


Assuntos
Sistema Enzimático do Citocromo P-450/genética , Desoxirribonucleases de Sítio Específico do Tipo II/genética , Heme/metabolismo , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Oxirredutases N-Desmetilantes/genética , Polimorfismo Genético/genética , Brasil , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Estudos de Casos e Controles , Citocromo P-450 CYP2E1 , Sistema Enzimático do Citocromo P-450/metabolismo , Desoxirribonuclease HpaII , Desoxirribonucleases de Sítio Específico do Tipo II/metabolismo , Etnicidade , Éxons/genética , Feminino , Ligação Genética/genética , Predisposição Genética para Doença , Genótipo , Homozigoto , Humanos , Isoleucina/genética , Masculino , Pessoa de Meia-Idade , Oxirredutases N-Desmetilantes/metabolismo , Ligação Proteica/genética , Fumar/genética , Valina/genética
6.
Cancer Epidemiol Biomarkers Prev ; 7(5): 413-7, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9610791

RESUMO

Okinawa, a group of islands that lie between the East China Sea and the Pacific Ocean, 2000 km south of the Japanese main islands, has a different profile of diseases, ethnicities, and cultures than does the rest of Japan. We examined an Ile462Val polymorphism (CYP1A1*2 allele) of cytochrome P450 IA1 in a hospital-based case-control study of lung cancer patients (247 cases and 185 controls) in Okinawa to ascertain the association of this variant with lung cancer. In addition, the distribution of this genotype was studied in populations from different areas of Japan, including Tokyo (n = 69) and Iwate (northern part of Japan; n = 81), as well as in a Chinese group from the Jiangsu province (n = 39) and in an Australian Caucasian group (n = 146). Genotype frequency in controls was not significantly different from area to area in Japan. In Okinawa, however, the genotype encoding Val/Val was associated with a significantly higher risk of lung cancer (odds ratio = 3.32, P = 0.013), especially of squamous cell carcinoma and small cell carcinoma (odds ratio = 4.85 and 9.35, respectively). The Val-encoding allele was less frequent in the Chinese population and was rare in Australian Caucasians. Thus, this study gives support to the value of the cytochrome P450 IA1 Ile462Val polymorphism as a practical high-risk marker of lung cancer in populations, especially those in southeast Asia, in which this variant is more common.


Assuntos
Citocromo P-450 CYP1A1/genética , Éxons/genética , Neoplasias Pulmonares/genética , Polimorfismo Genético/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Substituição de Aminoácidos/genética , Povo Asiático/genética , Austrália/epidemiologia , Estudos de Casos e Controles , China/epidemiologia , Humanos , Isoleucina/genética , Japão/epidemiologia , Neoplasias Pulmonares/epidemiologia , Masculino , Pessoa de Meia-Idade , Valina/genética , População Branca/genética
7.
Cancer Epidemiol Biomarkers Prev ; 8(8): 669-74, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10744126

RESUMO

The human homologue of the yeast OGG1 gene, hOGG1, has been cloned, and its genetic structure has been determined. Several polymorphisms in the hOGG1 gene were detected in the Japanese populations, and among them, the Ser-Cys polymorphism at codon 326 has been shown to have a functional difference in complementation of mutant Escherichia coli that is defective in the repair of 8-hydroxyguanine. Activity in the repair of 8-hydroxyguanine is greater in hOGG1-Ser326 protein than in hOGG1(326) protein. Because many environmental carcinogens produce 8-hydroxyguanine residue and mismatching to this modified base potentially causes oncogenic mutations, the capacity to repair these lesions can be involved in cancer susceptibility in human beings. We, therefore, examined allele distributions of the Ser326Cys polymorphism in a case-control study of male lung cancer in Okinawa. The analyses based on 241 cases and 197 hospital controls disclosed the following findings. (a) Those with the Cys/Cys genotype were at an increased risk of squamous cell carcinoma and nonadenocarcinoma compared to those with the Ser/Cys and those with the Ser/Ser genotypes combined. The odds ratios adjusted for age and smoking history were 3.01 (95% confidence interval, 1.33-6.83) and 2.18 (95% confidence interval, 1.05-4.54), respectively. (b) The odds ratios for other histological subtypes of lung cancer or those in total were not significant. Those for Cys/Cys or Ser/Cys genotype against Ser/Ser did not reach statistical significance in any cell type. (c) The distributions of this polymorphism varied for different populations (Chinese, Japanese, Micronesians, Melanesians, Hungarians, and Australian Caucasians), with much less prevalence of Cys allele in the latter three populations. Although our sample size was limited, these results indicate that the Ser326Cys variant may be related to squamous cell lung cancer susceptibility. The Cys/Cys genotype appears to be more susceptible to squamous cell carcinoma, although the risk is less than that previously reported to be associated with the CYP1A1 gene. Further studies are needed to assess the importance of the interpopulation variation to cancer susceptibility.


Assuntos
Carcinoma de Células Escamosas/genética , Dano ao DNA , Predisposição Genética para Doença , Guanina/análogos & derivados , Neoplasias Pulmonares/genética , N-Glicosil Hidrolases/metabolismo , Polimorfismo Genético , Adulto , Idoso , Idoso de 80 Anos ou mais , Alelos , Carcinoma de Células Escamosas/etiologia , Estudos de Casos e Controles , Cisteína/química , Guanina/metabolismo , Humanos , Japão , Neoplasias Pulmonares/etiologia , Masculino , Pessoa de Meia-Idade , N-Glicosil Hidrolases/química , Medição de Risco , Serina/química
8.
Cancer Lett ; 170(1): 53-61, 2001 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-11448535

RESUMO

Polymorphism of hOGG1 may be capable of serving as a genetic marker for individual susceptibility to various cancers because of its role in the repair of oxyradical DNA damage. We examined the distribution of the hOGG1 Ser326Cys polymorphism and its presumed correlation with gastric cancer risk in two case-control studies of different ethnic groups in São Paulo, Brazil. Potentially eligible Japanese (JB) and non-Japanese Brazilian (NJB) case subjects were defined as patients with newly diagnosed malignant neoplasms of the stomach in 13 hospitals in São Paulo. Ninety-six JBs and 236 NJBs were adopted as subjects. Two controls were matched for each JB case, and one control for each NJB case. The subjects were interviewed using a questionnaire and their blood samples were collected. A significant difference in the distribution of this polymorphism between the two ethnic groups was observed (chi(2)=58.3, P<0.01). The mutant type (Ser/Cys or Cys/Cys) was predominant (approximately 65%) in the JBs, but was only present in approximately 40% of the NJBs. Logistic regression analysis showed no significant increased risk for either the Ser/Cys or Cys/Cys type in either group. The odds ratios of the Cys allele for gastric cancer were 1.01 (95% confidence interval (CI): 0.52-1.93) in the JBs and 0.85 (95% CI: 0.57-1.26) in the NJBs. In the NJBs, a significant increased risk of smoking was shown only in the Ser/Ser type, and no increased risk was shown in the genotypes with the Cys allele. However, no statistically significant interactions were observed with smoking or other possible confounding factors. No statistically significant difference in the distribution of the polymorphism was observed between the intestinal type and diffuse type of gastric cancer in either the JBs or the NJBs. The ethnic difference in hOGG1 Ser326Cys polymorphism was much greater than the case-control difference, and this polymorphism is unlikely to be associated with gastric cancer.


Assuntos
N-Glicosil Hidrolases/genética , Neoplasias Gástricas/genética , Idoso , Alelos , Brasil/etnologia , Estudos de Casos e Controles , DNA-Formamidopirimidina Glicosilase , Éxons , Feminino , Predisposição Genética para Doença , Humanos , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade , Polimorfismo Genético , Neoplasias Gástricas/etnologia
9.
J Gastroenterol ; 35(4): 304-9, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10777162

RESUMO

Inflammatory pseudotumor (IPT) of the liver is a rare benign variant of hepatic masses, and its exact etiology has not been elucidated. We report a case of IPT associated with primary sclerosing cholangitis (PSC). The patient was a 50-year-old man admitted to our hospital because of jaundice. Abdominal ultrasonography (US) and computed tomography showed multiple dilations of the intrahepatic bile ducts and multiple masses in the liver. On magnetic resonance imaging, the masses were slightly hypointense on T1-weighted images and slightly hyperintense on T2-weighted images. On T1-weighted images after the bolus infusion of Gd chelate, the masses had no contrast enhancement, and they were hypointense in the arterial phase and portal venous phase. However, they were slightly enhanced and became almost isointense relative to the surrounding normal liver parenchyma in the delayed phase. Endoscopic retrograde cholangiography demonstrated multiple irregular strictures and dilations of the intrahepatic bile ducts. Angiography demonstrated no abnormal findings, but, interestingly, subsequent dynamic CO2-enhanced US showed a strongly hyperechoic string, indicating that an artery had penetrated through the hypoechoic mass. A US-guided percutaneous needle biopsy revealed that the lesions were morphologically comparable to IPT. After cholangiography and microscopic analysis of the tumor, the final diagnosis was determined to be IPT of the liver with PSC. A number of previous reports have suggested a possible relationship between IPT and PSC, based on pathological findings. This report confirmed, based on clinical findings, that PSC is one of the causes of hepatic IPT.


Assuntos
Colangite Esclerosante/diagnóstico , Granuloma de Células Plasmáticas/diagnóstico , Hepatopatias/diagnóstico , Ductos Biliares Intra-Hepáticos/patologia , Biópsia , Colangite Esclerosante/patologia , Diagnóstico Diferencial , Diagnóstico por Imagem , Granuloma de Células Plasmáticas/patologia , Humanos , Fígado/patologia , Hepatopatias/patologia , Masculino , Pessoa de Meia-Idade
10.
J Gastroenterol ; 32(5): 677-83, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9349997

RESUMO

A 17-year-old woman was admitted because of a liver tumor found incidentally by ultrasonography. Liver function was normal and there were no markers of hepatitis viruses or malignancy. Abdominal ultrasonography, computed tomography (CT), and magnetic resonance imaging revealed a mass (2 cm in diameter) in the lateral segment of the left lobe of the liver. The lesion was not detected by hepatic arteriography. However, dynamic CT with fast scanning and dynamic CO2-enhanced ultrasonography demonstrated initial central enhancement of the mass followed by centrifugal spread of enhancement to the periphery. Color Doppler flow imaging detected a central color spot, shown to be an artery by a pulsed Doppler spectrum analysis. Fine-needle biopsy confirmed a diagnosis of focal nodular hyperplasia. Dynamic CT with fast scanning, dynamic CO2-enhanced ultrasonography, and color Doppler flow imaging were useful in detecting the vascular pattern specific to focal nodular hyperplasia. Investigation of further cases with these novel imaging modalities should help to establish a comprehensive diagnostic procedure and thus avoid unnecessary surgery for focal nodular hyperplasia, which is a completely benign lesion.


Assuntos
Hepatopatias/diagnóstico , Fígado , Adolescente , Biópsia por Agulha , Diagnóstico Diferencial , Feminino , Humanos , Hiperplasia/diagnóstico , Fígado/irrigação sanguínea , Fígado/diagnóstico por imagem , Fígado/patologia , Neoplasias Hepáticas/irrigação sanguínea , Neoplasias Hepáticas/diagnóstico , Imageamento por Ressonância Magnética , Tomografia Computadorizada por Raios X , Ultrassonografia Doppler em Cores
11.
Eur J Gastroenterol Hepatol ; 10(12): 1045-50, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9895052

RESUMO

BACKGROUND: Endoscopic papillary balloon dilatation (EPBD) is generally considered a safe and effective technique for removal of common bile duct (CBD) stones. However, some reports have prompted concern about the risk of pancreatitis following the procedure, and it seems to be more difficult and to require adjunctive procedures more frequently in patients with large stones. AIMS: To analyse the factors influencing pancreatitis after the procedure, and to examine which is the more suitable adjunct for treating large stones, mechanical lithotripsy (ML) or extracorporeal shockwave lithotripsy (ESWL). PATIENTS AND METHODS: EPBD was performed in 92 patients, including 40 with large stones (> or = 12 mm). These 40 patients were randomly assigned to two groups receiving ML or ESWL to fragment stones (20 patients each). RESULTS: Complete ductal clearance was obtained in all 92 patients. Significant elevation of the serum amylase level compared with the prior value (> 300 IU/l) was observed in 26 (28%), and eight (8.7%) developed clinical pancreatitis. To assess the influence of various factors on the amylase level, multivariate analysis was used. The number of stones and the time required for treatment had a significant influence on the incidence of increased amylase level (P < 0.05), and ML also significantly increased it (P < 0.05). On the other hand, the amylase level remained low in the ESWL group. ML caused elevation of amylase level in 11 patients (55%), while three (15%) had elevation after ESWL. CONCLUSIONS: In patients with multiple stones, elevation of the amylase level is more frequent. This seems to be because repeated cannulation and much time is required for treatment. In patients with large stones, the rate was also high if ML was used, but was low when ESWL was used. ESWL may reduce the incidence of pancreatitis.


Assuntos
Cateterismo , Endoscopia , Cálculos Biliares/terapia , Litotripsia , Idoso , Idoso de 80 Anos ou mais , Amilases/sangue , Terapia Combinada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
12.
Nihon Koshu Eisei Zasshi ; 48(11): 914-22, 2001 Nov.
Artigo em Japonês | MEDLINE | ID: mdl-11774705

RESUMO

OBJECTIVE: Legionnaires disease has been attributed to Legionella spp. in the water distribution systems of buildings. However, recently cases due to contamination of thermal-bath water have been reported in Japan. In this investigation, we examined the supervision of baths and the presence of Legionella spp. in thermal-bath water of homes for the elderly in Toyohashi city. METHODS: The research was conducted through questionnaires on bathing facilities at 50 sites. Thermal baths were found to be installed at 14 of the sites. We then tested 22 samples from the 14 sites for Legionella spp. and other materials. RESULTS: From the genus Legionella, only Legionella pneumophila was detected, in 8 samples from 4 sites. Coliforms were also detected. Moreover, disinfectant was not detected in any of the Legionella positive samples of bath water. Legionella positive sites had, however, been replacing their water once a day. CONCLUSIONS: These findings indicate that the use of disinfectant and the proper supervision of bathing facilities are important in controlling Legionella spp. Legionnaires disease can be averted in homes for the elderly through appropriate measures.


Assuntos
Banhos/efeitos adversos , Instituição de Longa Permanência para Idosos , Legionella/isolamento & purificação , Legionelose/epidemiologia , Microbiologia da Água/normas , Idoso , Humanos , Japão/epidemiologia
17.
Hum Genet ; 93(1): 74-6, 1994 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8270259

RESUMO

Screening for lactate dehydrogenase (LDH) subunit deficiencies was performed on 2880 blood samples from healthy individuals in the Fukuoka Prefecture in Japan by means of electrophoresis. The frequencies of heterozygotes with either LDH-A or LDH-B deficiency were found to be 0.104% at each locus. These estimated frequencies of either LDH-A or LDH-B deficiencies were slightly lower than, but not significantly different from, those found previously in Shizuoka Prefecture. The genetic mutations in individuals heterozygous for LDH-B deficiency were analyzed by the polymerase chain reaction and DNA conformation polymorphism. Abnormal migration patterns were observed in individuals heterozygous for LDH-B deficiency. Subsequent sequence determination of the mutant alleles revealed three novel mutations: an eight-base duplication in exon 3, a four-base duplication in exon 4, and a one-base deletion in exon 7 of the LDH-B gene. These three mutations result in frame-shift translation and premature termination. In addition, the mutations resulting in the duplication of eight or four nucleotides appear to cause a decrease in the levels of LDH-B mRNA.


Assuntos
L-Lactato Desidrogenase/deficiência , L-Lactato Desidrogenase/genética , Mutação , Sequência de Aminoácidos , Sequência de Bases , Eletroforese em Gel de Poliacrilamida , Eritrócitos/enzimologia , Éxons/genética , Mutação da Fase de Leitura , Testes Genéticos , Humanos , Isoenzimas , Japão , Programas de Rastreamento , Dados de Sequência Molecular , Família Multigênica , Reação em Cadeia da Polimerase
18.
Mol Microbiol ; 23(6): 1203-13, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9106211

RESUMO

Catabolite repression of Bacillus subtilis catabolic operons is supposed to occur via a negative regulatory mechanism involving the recognition of a cis-acting catabolite-responsive element (cre) by a complex of CcpA, which is a member of the GalR-Lacl family of bacterial regulatory proteins, and the seryl-phosphorylated form of HPr (P-ser-HPr), as verified by recent studies on catabolite repression of the gnt operon. Analysis of the gnt promoter region by deletions and point mutations revealed that in addition to the cre in the first gene (gntR) of the gnt operon (credown), this operon contains another cre located in the promoter region (creup). A translational gntR'-'lacZ fusion expressed under the control of various combinations of wild-type and mutant credown and creup was integrated into the chromosomal amyE locus, and then catabolite repression of beta-galactosidase synthesis in the resultant integrants was examined. The in vivo results implied that catabolite repression exerted by creup was probably independent of catabolite repression exerted by credown; both creup and credown catabolite repression involved CcpA. Catabolite repression exerted by creup was independent of P-ser-HPr, and catabolite repression exerted by credown was partially independent of P-ser-HPr. DNase I footprinting experiments indicated that a complex of CcpA and P-ser-HPr did not recognize creup, in contrast to its specific recognition of credown. However, CcpA complexed with glucose-6-phosphate specifically recognized creup as well as credown, but the physiological significance of this complexing is unknown.


Assuntos
Bacillus subtilis/metabolismo , Proteínas de Bactérias , Proteína Receptora de AMP Cíclico/farmacologia , Elementos Facilitadores Genéticos , Regulação Bacteriana da Expressão Gênica/fisiologia , Genes Bacterianos/fisiologia , Óperon/genética , Bacillus subtilis/genética , Sequência de Bases , Proteína Receptora de AMP Cíclico/genética , Análise Mutacional de DNA , DNA Recombinante/genética , DNA Recombinante/fisiologia , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Regulação Bacteriana da Expressão Gênica/genética , Genes Bacterianos/genética , Glucose-6-Fosfato/genética , Glucose-6-Fosfato/metabolismo , Dados de Sequência Molecular , Regiões Promotoras Genéticas/genética , Regiões Promotoras Genéticas/fisiologia , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo
19.
J Biol Chem ; 270(36): 21206-19, 1995 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-7673154

RESUMO

A second protein-tyrosine kinase (PTK) of the focal adhesion kinase (FAK) subfamily, cell adhesion kinase beta (CAK beta), was identified by cDNA cloning. The rat CAK beta is a 115.7-kDa PTK that contains N- and C-terminal domains of 418 and 330 amino acid residues besides the central kinase domain. The rat CAK beta has a homology with mouse FAK over their entire lengths except for the extreme N-terminal 88 residues and shares 45% overall sequence identity (60% identical in the catalytic domain), which indicates that CAK beta is a protein structurally related to but different from FAK. The CAK beta gene is less evenly expressed in a variety of rat organs than the FAK gene. Anti-CAK beta antibody immunoprecipitated a 113-kDa protein from rat brain, 3Y1 fibroblasts, and COS-7 cells transfected with CAK beta cDNA. The tyrosine-phosphorylated state of CAK beta was not reduced on trypsinization, nor enhanced in response to plating 3Y1 cells onto fibronectin. CAK beta localized to sites of cell-to-cell contact in COS-7 transfected with CAK beta cDNA, in which FAK was found at the bottom of the cells. Thus, CAK beta is a PTK possibly participating in the signal transduction regulated by cell-to-cell contacts.


Assuntos
Moléculas de Adesão Celular/genética , Proteínas Tirosina Quinases/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Encéfalo/enzimologia , Moléculas de Adesão Celular/metabolismo , Linhagem Celular , Clonagem Molecular , DNA Complementar , Quinase 1 de Adesão Focal , Quinase 2 de Adesão Focal , Proteína-Tirosina Quinases de Adesão Focal , Humanos , Dados de Sequência Molecular , Fosforilação , Proteínas Tirosina Quinases/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Homologia de Sequência de Aminoácidos , Células Tumorais Cultivadas , Tirosina/metabolismo
20.
Hum Genet ; 98(4): 508-10, 1996 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8792832

RESUMO

Cell adhesion kinase beta (CAK beta) is the second protein-tyrosine kinase of the focal adhesion kinase subfamily with large N- and C-domains in addition to the central kinase domain. The cDNA of the human CAK beta has been cloned and used as a probe for the assignment of this gene by fluorescence in situ hybridization. CAK beta is sublocalized on chromosome 8p21.1, a locus frequently involved in allelic losses in colorectal cancers and prostate carcinomas.


Assuntos
Cromossomos Humanos Par 8 , Proteínas Tirosina Quinases/genética , Animais , Mapeamento Cromossômico , Neoplasias Colorretais/genética , Sondas de DNA , DNA Complementar , Quinase 2 de Adesão Focal , Humanos , Hibridização in Situ Fluorescente , Cariotipagem , Masculino , Dados de Sequência Molecular , Neoplasias da Próstata/genética , Ratos
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