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1.
J Fish Dis ; 39(6): 667-72, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26096292

RESUMO

Foodborne disease outbreaks caused by raw olive flounders (Paralichthys olivaceus) parasitized with Kudoa septempunctata have been reported in Japan. Origins of olive flounders consumed in Japan vary, being either domestic or imported, and aquaculture-raised or natural. Although it is unknown whether different sources are associated with different outcomes, it is desirable to identify whether this is the case by determining whether unique K. septempunctata strains occur and if so, whether some are associated with foodborne illness. We here developed an intraspecific genotyping method, using the sequence variation of mitochondrial genes. We collected olive flounder samples from foodborne disease outbreaks, domestic fish farms or quarantine offices and investigated whether K. septempunctata genotype is associated with pathogenicity or geographic origin. The 104 samples were classified into three genotypes, ST1, ST2 and ST3. Frequency of symptomatic cases differed by genotypes, but the association was not statistically significant. Whereas K. septempunctata detected from aquaculture-raised and natural fish from Japan were either ST1 or ST2, those from fish inspected at quarantine from Korea to Japan were ST3. Our method can be applied to phylogeographic analysis of K. septempunctata and contribute to containing the foodborne disease. The genotype database is hosted in the PubMLST website (http://pubmlst.org/kseptempunctata/).


Assuntos
Doenças dos Peixes/epidemiologia , Doenças Transmitidas por Alimentos/epidemiologia , Myxozoa/genética , Doenças Parasitárias em Animais/epidemiologia , Alimentos Marinhos/intoxicação , Animais , Doenças dos Peixes/parasitologia , Linguados , Doenças Transmitidas por Alimentos/parasitologia , Variação Genética , Genoma Mitocondrial , Geografia , Humanos , Incidência , Japão/epidemiologia , Myxozoa/classificação , Doenças Parasitárias em Animais/parasitologia , República da Coreia/epidemiologia , Estações do Ano , Análise de Sequência de DNA/veterinária
2.
Diabet Med ; 30(3): 326-32, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22998091

RESUMO

AIMS: To describe the burden of diabetes mellitus and impaired fasting glucose in middle-aged residents (35-64 years) in an urban area of Sri Lanka. METHODS: A cross-sectional survey was conducted in the Ragama Medical Officer of Health area, from which 2986 participants (1349 men and 1637 women) were randomly selected from the electoral registry between January and December 2007. The participants underwent a physical examination and had their height, weight, waist and hip circumferences and blood pressure measured by trained personnel. Fasting blood samples were taken for measurement of glucose, HbA(1c) and lipids. The prevalence of diabetes (fasting plasma glucose > 7 mmol/l) and impaired fasting glycaemia (fasting plasma glucose 5.6-6.9 mmol/l) and major predictors of diabetes in Sri Lanka were estimated from the population-based data. RESULTS: Age-adjusted prevalence of diabetes mellitus in this urban population was 20.3% in men and 19.8% in women. Through the present screening, 263 patients with diabetes and 1262 with impaired fasting glucose levels were identified. The prevalence of newly detected diabetes was 35.7% of all patients with diabetes. Among patients with diabetes, only 23.8% were optimally controlled. In the regression models, high BMI, high waist circumference, high blood pressure and hypercholesterolaemia increased the fasting plasma glucose concentration, independent of age, sex and a family history of diabetes. CONCLUSIONS: Our data demonstrate the heavy burden of diabetes in this urban population. Short- and long-term control strategies are required, not only for optimal therapy among those affected, but also for nationwide primary prevention of diabetes.


Assuntos
Diabetes Mellitus/epidemiologia , Adulto , Distribuição por Idade , Glicemia/metabolismo , Efeitos Psicossociais da Doença , Estudos Transversais , Diabetes Mellitus/sangue , Jejum/sangue , Feminino , Hemoglobinas Glicadas/metabolismo , Humanos , Hipoglicemia/epidemiologia , Masculino , Pessoa de Meia-Idade , Prevalência , Análise de Regressão , Fatores de Risco , Distribuição por Sexo , Sri Lanka/epidemiologia , Saúde da População Urbana/estatística & dados numéricos
3.
Int J Immunogenet ; 40(2): 126-30, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22862923

RESUMO

Human leucocyte antigen (HLA) study in patients with systemic lupus erythematosus (SLE) has been investigated in various countries, but the results are still inconclusive. This study was performed to investigate the association between HLA-DR and SLE in patients in northern Thailand. HLA-DR subtyping was performed in 70 patients with SLE and 99 normal healthy controls living in northern Thailand using the INNO-LiPA HLA-DR Decoder kit (Innogenetics) and MICRO SSP HLA DNA Typing kit (One Lambda) for reconfirmation. The allele frequency (AF) of DRB5*01:01 in SLE was significantly higher than in the controls [25.7% vs. 14.6%, P = 0.012, Pc = 0.048, OR = 2.02 (95%CI = 1.17-3.48)]. The AF of DRB1*15:01 and DRB1*16:02 showed a nonsignificant tendency to be higher in SLE (10.7% vs. 8.1%, and 17.9% vs. 11.1%). Interestingly, the DRB5*01:01 allele linked to DRB1*16:02 in 47.2% of SLE and 37.9% of controls, and the prevalence of the DRB1*16:02-DRB5*01:01 haplotype was higher in the patients with SLE [12.1% vs. 5.6%, P = 0.044, OR = 2.35 (95%CI = 1.06-5.19)]. The DRB1*16:02 linked to DRB5*02:02 and *02:03 in 18.2% and 31.8% of controls, respectively, and linked to DRB5*02:03 in 32.0% of SLE patients. The frequency of DRB1*03:01 and *15:02 alleles was not increased in Thai SLE. There was no significant association between DRB5*01:01 and any auto-antibodies or clinical manifestations of SLE. DRB5*01:01 is associated with Thai SLE, and the association is stronger than that of DRB1*15:01. The genetic contribution of DRB5*01:01 is due partially to the linkage disequilibrium between DRB1*16:02 and DRB5*01:01 in the northern Thai population.


Assuntos
Cadeias HLA-DRB1/genética , Cadeias HLA-DRB5/genética , Lúpus Eritematoso Sistêmico/genética , Lúpus Eritematoso Sistêmico/imunologia , Adulto , Feminino , Frequência do Gene , Predisposição Genética para Doença , Cadeias HLA-DRB1/imunologia , Cadeias HLA-DRB5/imunologia , Humanos , Desequilíbrio de Ligação , Masculino , Pessoa de Meia-Idade , Tailândia
4.
Diabetologia ; 55(10): 2660-2666, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22869321

RESUMO

AIMS/HYPOTHESIS: Genome-wide association studies have shown that variants near the melanocortin 4 receptor gene (MC4R) (rs17782313 and rs12970134) are associated with risk of obesity in Europeans. As obesity is associated with an increased risk of type 2 diabetes, many studies have investigated the association between polymorphisms near the MC4R gene and type 2 diabetes risk across different ethnic populations, with inconsistent results. In this study, we performed a meta-analysis to clarify the association of variants near MC4R with type 2 diabetes risk. METHODS: Published literature from PubMed and Embase was retrieved. All studies that evaluated the association of at least one of the two MC4R polymorphism(s) with type 2 diabetes were included in the study. Pooled ORs with 95% CIs were calculated using the fixed-effects model. RESULTS: A total of 19 studies (comprising 34,195 cases and 89,178 controls) of the rs17782313 polymorphism (or its proxy rs12970134) were included in the meta-analysis. The results indicated that the rs17782313 polymorphism was significantly associated with type 2 diabetes risk among the overall study population (OR 1.10, 95% CI 1.07, 1.13, p = 2.83 × 10(-12) [Z test], I(2) = 9.1%, p = 0.345 [heterogeneity]). The association remained significant even after adjustment for body mass index (BMI) (OR 1.06, 95% CI 1.03, 1.09, p = 2.14 × 10(-5) [Z test], I(2) = 4.9%, p = 0.397 [heterogeneity]). Further sensitivity analysis confirmed the statistically significant association of rs17782313 polymorphism with type 2 diabetes, and no publication bias was detected. CONCLUSIONS/INTERPRETATION: The present meta-analysis confirmed the significant association of the rs17782313 polymorphism near the MC4R gene with type 2 diabetes risk, which was independent of BMI.


Assuntos
Diabetes Mellitus Tipo 2/genética , Polimorfismo de Nucleotídeo Único/genética , Receptor Tipo 4 de Melanocortina/genética , Adulto , Idoso , Estudos de Casos e Controles , Diabetes Mellitus Tipo 2/epidemiologia , Feminino , Estudo de Associação Genômica Ampla , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco
5.
Diabetologia ; 55(4): 981-95, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22109280

RESUMO

AIMS/HYPOTHESIS: FTO harbours the strongest known obesity-susceptibility locus in Europeans. While there is growing evidence for a role for FTO in obesity risk in Asians, its association with type 2 diabetes, independently of BMI, remains inconsistent. To test whether there is an association of the FTO locus with obesity and type 2 diabetes, we conducted a meta-analysis of 32 populations including 96,551 East and South Asians. METHODS: All studies published on the association between FTO-rs9939609 (or proxy [r (2) > 0.98]) and BMI, obesity or type 2 diabetes in East or South Asians were invited. Each study group analysed their data according to a standardised analysis plan. Association with type 2 diabetes was also adjusted for BMI. Random-effects meta-analyses were performed to pool all effect sizes. RESULTS: The FTO-rs9939609 minor allele increased risk of obesity by 1.25-fold/allele (p = 9.0 × 10(-19)), overweight by 1.13-fold/allele (p = 1.0 × 10(-11)) and type 2 diabetes by 1.15-fold/allele (p = 5.5 × 10(-8)). The association with type 2 diabetes was attenuated after adjustment for BMI (OR 1.10-fold/allele, p = 6.6 × 10(-5)). The FTO-rs9939609 minor allele increased BMI by 0.26 kg/m(2) per allele (p = 2.8 × 10(-17)), WHR by 0.003/allele (p = 1.2 × 10(-6)), and body fat percentage by 0.31%/allele (p = 0.0005). Associations were similar using dominant models. While the minor allele is less common in East Asians (12-20%) than South Asians (30-33%), the effect of FTO variation on obesity-related traits and type 2 diabetes was similar in the two populations. CONCLUSIONS/INTERPRETATION: FTO is associated with increased risk of obesity and type 2 diabetes, with effect sizes similar in East and South Asians and similar to those observed in Europeans. Furthermore, FTO is also associated with type 2 diabetes independently of BMI.


Assuntos
Povo Asiático/genética , Diabetes Mellitus Tipo 2/genética , Obesidade/genética , Proteínas/genética , Adulto , Dioxigenase FTO Dependente de alfa-Cetoglutarato , Feminino , Estudos de Associação Genética , Predisposição Genética para Doença , Genótipo , Humanos , Masculino , Polimorfismo de Nucleotídeo Único
6.
Diabetologia ; 54(6): 1350-9, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21369819

RESUMO

AIMS/HYPOTHESIS: In populations of East Asian descent, we performed a replication study of loci previously identified in populations of European descent as being associated with obesity measures such as BMI and type 2 diabetes. METHODS: We genotyped 14 single nucleotide polymorphisms (SNPs) from 13 candidate loci that had previously been identified by genome-wide association meta-analyses for obesity measures in Europeans. Genotyping was done in 18,264 participants from two general Japanese populations. For SNPs showing an obesity association in Japanese individuals, we further examined diabetes associations in up to 6,781 cases and 7,307 controls from a subset of the original, as well as from additional populations. RESULTS: Significant obesity associations (p < 0.1 two-tailed, concordant direction with previous reports) were replicated for 11 SNPs from the following ten loci in Japanese participants: SEC16B, TMEM18, GNPDA2, BDNF, MTCH2, BCDIN3D-FAIM2, SH2B1-ATP2A1, FTO, MC4R and KCTD15. The strongest effect was observed at TMEM18 rs4854344 (p = 7.1 × 10(-7) for BMI). Among the 11 SNPs showing significant obesity association, six were also associated with diabetes (OR 1.05-1.17; p = 0.04-2.4 × 10(-7)) after adjustment for BMI in the Japanese. When meta-analysed with data from the previous reports, the BMI-adjusted diabetes association was found to be highly significant for the FTO locus in East Asians (OR 1.13; 95% CI 1.09-1.18; p = 7.8 × 10(-10)) with substantial inter-ethnic heterogeneity (p = 0.003). CONCLUSIONS/INTERPRETATION: We confirmed that ten candidate loci are associated with obesity measures in the general Japanese populations. Six (of ten) loci exert diabetogenic effects in the Japanese, although relatively modest in size, and independently of increased adiposity.


Assuntos
Povo Asiático/genética , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/genética , Predisposição Genética para Doença/genética , Obesidade/epidemiologia , Obesidade/genética , Polimorfismo de Nucleotídeo Único/genética , Adulto , Idoso , Povo Asiático/etnologia , Índice de Massa Corporal , Fator Neurotrófico Derivado do Encéfalo/genética , Estudos de Casos e Controles , Comorbidade , Diabetes Mellitus Tipo 2/etnologia , Feminino , Predisposição Genética para Doença/etnologia , Genótipo , Humanos , Japão , Masculino , Proteínas de Membrana/genética , Proteínas de Membrana Transportadoras/genética , Pessoa de Meia-Idade , Proteínas de Transporte da Membrana Mitocondrial , Proteínas Mitocondriais/genética , Obesidade/etnologia
7.
Diabetologia ; 53(2): 299-308, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19937311

RESUMO

AIMS/HYPOTHESIS: To test fasting glucose association at four loci recently identified or verified by genome-wide association (GWA) studies of European populations, we performed a replication study in two Asian populations. METHODS: We genotyped five common variants previously reported in Europeans: rs1799884 (GCK), rs780094 (GCKR), rs560887 (G6PC2-ABCB11) and both rs1387153 and rs10830963 (MTNR1B) in the general Japanese (n = 4,813) and Sri Lankan (n = 2,319) populations. To identify novel variants, we further examined genetic associations near each locus by using GWA scan data on 776 non-diabetic Japanese samples. RESULTS: Fasting glucose association was replicated for the five single nucleotide polymorphisms (SNPs) at p < 0.05 (one-tailed test) in South Asians (Sri Lankan) as well as in East Asians (Japanese). In fine-mapping by GWA scan data, we identified in the G6PC2-ABCB11 region a novel SNP, rs3755157, with significant association in Japanese (p = 2.6 x 10(-8)) and Sri Lankan (p = 0.001) populations. The strength of association was more prominent at rs3755157 than that of the original SNP rs560887, with allelic heterogeneity detected between the SNPs. On analysing the cumulative effect of associated SNPs, we found the per-allele gradients (beta = 0.055 and 0.069 mmol/l in Japanese and Sri Lankans, respectively) to be almost equivalent to those reported in Europeans. CONCLUSIONS/INTERPRETATION: Fasting glucose association at four tested loci was proven to be replicable across ethnic groups. Despite this overall consistency, ethnic diversity in the pattern and strength of linkage disequilibrium certainly exists and can help to appreciably reduce potential causal variants after GWA studies.


Assuntos
Transportadores de Cassetes de Ligação de ATP/genética , Proteínas Adaptadoras de Transdução de Sinal/genética , Povo Asiático/genética , Glicemia/metabolismo , Jejum/fisiologia , Variação Genética , Glucose-6-Fosfatase/genética , Polimorfismo de Nucleotídeo Único , Proteínas Serina-Treonina Quinases/genética , Receptor MT2 de Melatonina/genética , Membro 11 da Subfamília B de Transportadores de Cassetes de Ligação de ATP , Alelos , Mapeamento Cromossômico/métodos , Etnicidade/genética , Quinases do Centro Germinativo , Haplótipos/genética , Humanos , Japão , Análise de Regressão , Sri Lanka
8.
J Exp Med ; 169(6): 2263-8, 1989 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-2732676

RESUMO

The association between HLA-DR4 and rheumatoid arthritis (RA) has been established in many ethnic groups. To clarify the determinant of susceptibility to RA, a polymorphic segment of the HLA-DRB gene was amplified in vitro by polymerase chain reaction and analyzed with oligonucleotide probes specific for the HLA-DR4 DNA sequences. A particular sequence encoding amino acids Gln70-Arg71-Arg72-Ala73-Ala74 showed a strong association with RA (p less than 0.005, relative risk 6.0). This amino acid sequence occurs in the DRB molecules with three RA-associated specificities, DR4/Dw14, DR4/Dw15, and DR1. DR4/Dw4, which is common in Caucasian RA patients, has a strikingly similar amino acid sequence Gln70-Lys71-Arg72-Ala73-Ala74 in terms of polarity and charge profiles. Other RA nonassociated sequences differ from this sequence by at least one amino acid substitution that causes the change of the net charge. The composition of amino acid residues at the positions 70-74 may play a crucial role in the pathogenesis of RA.


Assuntos
Artrite Reumatoide/etiologia , Antígenos HLA-DR/isolamento & purificação , Sequência de Aminoácidos , Artrite Reumatoide/genética , Artrite Reumatoide/imunologia , Sequência de Bases , Suscetibilidade a Doenças , Amplificação de Genes , Antígenos HLA-DR/genética , Humanos , Dados de Sequência Molecular , Sondas de Oligonucleotídeos
9.
Hepatol Int ; 13(3): 314-322, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30539516

RESUMO

INTRODUCTION: While patients with non-alcoholic fatty liver disease (NAFLD) are mostly overweight or obese, some are lean. METHODS: In a community-based follow-up study (baseline and follow-up surveys performed in 2007 and 2014), we investigated and compared the clinical characteristics, body composition, metabolic associations and outcomes, and other risk factors among individuals with lean (BMI < 23 kg/m2) NAFLD, non-lean (BMI ≥ 23 kg/m2) NAFLD and those without NAFLD. To investigate associations of selected genetic variants, we performed a case-control study between lean NAFLD cases and lean non-NAFLD controls. RESULTS: Of the 2985 participants in 2007, 120 (4.0%) had lean NAFLD and 816 (27.3%) had non-lean NAFLD. 1206 (40.4%) had no evidence of NAFLD (non-NAFLD). Compared to non-lean NAFLD, lean NAFLD was commoner among males (p < 0.001), and had a lower prevalence of hypertension (p < 0.001) and central obesity (WC < 90 cm for males, < 80 cm for females) (p < 0.001) without prominent differences in the prevalence of other metabolic comorbidities at baseline survey. Of 2142 individuals deemed as either NAFLD or non-NAFLD in 2007, 704 NAFLD individuals [84 lean NAFLD, 620 non-lean NAFLD] and 834 individuals with non-NAFLD in 2007 presented for follow-up in 2014. There was no difference in the occurrence of incident metabolic comorbidities between lean NAFLD and non-lean NAFLD. Of 294 individuals who were non-NAFLD in 2007 and lean in both 2007 and 2014, 84 (28.6%) had developed lean NAFLD, giving an annual incidence of 4.1%. Logistic regression identified the presence of diabetes at baseline, increase in weight from baseline to follow-up and a higher educational level as independent risk factors for the development of incident lean NAFLD. NAFLD association of PNPLA3 rs738409 was more pronounced among lean individuals (one-tailed p < 0.05) compared to the whole cohort sample. CONCLUSION: Although lean NAFLD constitutes a small proportion of NAFLD, the risk of developing incident metabolic comorbidities is similar to that of non-lean NAFLD. A PNPLA3 variant showed association with lean NAFLD in the studied population. Therefore, lean NAFLD also warrants careful evaluation and follow-up.


Assuntos
Hepatopatia Gordurosa não Alcoólica/epidemiologia , Adulto , Idoso , Povo Asiático/genética , Composição Corporal , Índice de Massa Corporal , Estudos de Casos e Controles , Estudos de Coortes , Feminino , Estudo de Associação Genômica Ampla , Humanos , Masculino , Pessoa de Meia-Idade , Hepatopatia Gordurosa não Alcoólica/sangue , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/genética , Prevalência , Estudos Prospectivos , Fatores de Risco , Sri Lanka/epidemiologia
10.
Clin Exp Rheumatol ; 26(2): 337-9, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18565258

RESUMO

OBJECTIVE: To study the contribution of the CD14 gene to the pathogenesis of rheumatoid arthritis (RA) in Japanese patients. METHODS: CD14 genotyping was carried out at the -159C/T dimorphic site in 97 RA patients and 104 normal subjects by the PCR-RFLP (restriction fragment length polymorphism) METHOD: HLA-DRB1 genotyping was performed by the PCR-SSCP (sequence specific conformational polymorphism) method. RESULTS: The -159C/T dimorphism is not associated with whole RA or with female RA, and the results were compatible with a previous report from Germany. The -159C/T dimorphism was not associated with rheumatoid factor (RF)-positive RA, although the -159T allele tended to be associated with RF in the German report. The -159C/T dimorphism showed no association even in RA patients with the RA-susceptibility HLA-DRB1*0405. The -159T allele was prevalent in Japanese controls. CONCLUSION: The CD14 gene is very unlikely to be genetically involved in the pathogenesis of Japanese RA.


Assuntos
Artrite Reumatoide/etnologia , Artrite Reumatoide/genética , Receptores de Lipopolissacarídeos/genética , Idoso , Feminino , Predisposição Genética para Doença/etnologia , Genótipo , Humanos , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade , Polimorfismo de Fragmento de Restrição , Polimorfismo Conformacional de Fita Simples , Prevalência , Regiões Promotoras Genéticas/genética
11.
Cancer Res ; 44(10): 4272-5, 1984 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-6432307

RESUMO

Several lines of evidence have suggested, but not proved, that polyamines are associated with DNA in intact cells. In an attempt to investigate the roles of polyamines in gene-associated functions, we examined the effects of polyamine depletion on the spontaneous mutation rate in a rat basophilic leukemia cell line. The frequency of 6-thioguanine-resistant mutant cells increased by approximately 9-fold as a result of the treatment with alpha-difluoromethylornithine, a potent inhibitor of ornithine decarboxylase (EC 4.1.1.17). This increase was prevented by supplementing the cultures with putrescine, suggesting that polyamine depletion, but not the direct mutagenic action of the enzyme inhibitor, is responsible for the mutant-increasing effect. These results suggest that polyamines may participate in the conservation of genetic information at either the chromosome or gene level.


Assuntos
Mutação , Inibidores da Ornitina Descarboxilase , Ornitina/análogos & derivados , Poliaminas/metabolismo , Tioguanina/toxicidade , Animais , Basófilos/efeitos dos fármacos , Resistência a Medicamentos , Eflornitina , Leucemia Experimental/patologia , Metilnitronitrosoguanidina/toxicidade , Ornitina/farmacologia , Ratos
12.
Biochim Biophys Acta ; 743(3): 323-30, 1983 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-6830814

RESUMO

Kynurenine aminotransferase (L-kynurenine:2-oxoglutarate aminotransferase (cyclizing), EC 2.6.1.7) was purified 378-fold from rat liver mitochondria by digitonin solubilization, heat treatment, DEAE-Sepharose CL-6B chromatography, Sephadex G-100 gel filtration, hydroxyapatite chromatography and chromatofocusing. Elution patterns of alpha-aminoadipate aminotransferase (EC 2.6.1.39) activity were identical with those of kynurenine aminotransferase activity on all column chromatographies. The ratios of the two specific activities were constant throughout the purification. On polyacrylamide gel electrophoresis both activities were detected at the same position. Both enzymatic activities showed the same inactivation curves upon heat inactivation at various temperatures. alpha-Aminoadipate showed competitive inhibiton against kynurenine or 3-hydroxykynurenine. alpha-Ketoadipate was utilized in the kynurenine aminotransferase reaction as an amino acceptor in place of alpha-ketoglutarate. The Km value for alpha-ketoadipate was 10 microM, lower than for alpha-ketoglutarate. These observations indicate that kynurenine aminotransferase is identical with alpha-aminoadipate aminotransferase. The Km values of purified kynurenine aminotransferase were determined at pH 6.5 as: kynurenine, 4.3 mM; pyridoxal 5'-phosphate, 4.2 microM; alpha-ketoglutarate, 20 microM (kynurenine substrate), and 3-hydroxykynurenine, 5.7 mM; pyridoxal 5'-phosphate, 1.7 microM; alpha-ketoglutarate, 13 microM (3-hydroxy-kynurenine substrate). The enzyme was strongly inhibited by Hg2+ and p-chloromercuribenzoate.


Assuntos
Liases , Mitocôndrias Hepáticas/enzimologia , Transaminases/metabolismo , 2-Aminoadipato Transaminase , Animais , Isoenzimas/isolamento & purificação , Isoenzimas/metabolismo , Cinética , Masculino , Piruvatos/metabolismo , Ratos , Ratos Endogâmicos , Especificidade por Substrato , Transaminases/isolamento & purificação
13.
Biochim Biophys Acta ; 1252(2): 185-8, 1995 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-7578221

RESUMO

Amino-acid sequence of kynureninase purified from rat liver cytosol was determined by an amino-acid sequencer. The enzyme was degraded to small peptides with cyanogen bromide, TPCK-trypsin, endoproteinase Glu-C, lysyl endoprotease and alpha-chymotrypsin. The enzyme subunit consisted of 464 amino acids, and the molecular weight of subunit was determined to be 52,510. The coenzyme pyridoxal phosphate-binding residue was lysine of which position was 276, and the N-terminal residue was N-acetylmethionine. The homology search between this enzyme and the other pyridoxal phosphate-dependent enzymes showed that kynureninase was similar to mitochondrial aspartate aminotransferase, and also to cystathionine gamma-synthase and gamma-lyase to a lesser extent.


Assuntos
Hidrolases/isolamento & purificação , Fígado/enzimologia , Sequência de Aminoácidos , Animais , Sítios de Ligação , Brometo de Cianogênio , Citosol/enzimologia , Hidrolases/química , Masculino , Dados de Sequência Molecular , Fragmentos de Peptídeos/química , Ratos , Ratos Wistar , Alinhamento de Sequência
14.
Biochim Biophys Acta ; 882(2): 228-33, 1986 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-3011114

RESUMO

WI-L2 cells (a B-lymphoblastoid cell line) were more resistant than CEM cells (a T-lymphoblastoid cell line) to deoxyadenosine, ara-A (9-beta-D-arabinofuranosyladenine), or ara-C (1-beta-D-arabinofuranosylcytosine) inhibition. This was caused by a difference in the composition of cytosol 5'-nucleotidases between WI-L2 and CEM cells. In intact cells, the endogenous production of deoxyadenosine from WI-L2 cells deficient in adenosine kinase (EC 2.7.1.20) and deoxycytidine kinase (EC 2.7.1.74) was consistently high, despite changes in endogenous adenosine production. Endogenous production of deoxyadenosine from CEM cells deficient in adenosine kinase and deoxycytidine kinase was, however, coordinated with endogenous adenosine production. In broken cells, cytosol dAMPase (2'-deoxyadenosine 5'-monophosphate 5'-nucleotidase) activity of WI-L2 cells was 3-5-fold higher than that of CEM cells. dAMPase activity could be separated from ATP-activated IMPase (inosine 5'-monophosphate 5'-nucleotidase) by gel filtration (molecular weight: dAMPase; 39,000-46,000; ATP-activated IMPase, greater than 150,000). Cytosol ATP-activated IMPase and dAMPase were isolated by phosphocellulose or DEAE-Bio-Gel A chromatography from non-specific phosphatases. The ATP-activated IMPase showed only marginal activity towards dAMP (2'-deoxyadenosine 5'-monophosphate), ara-AMP (9-beta-D-arabinofuranosyladenine 5'-monophosphate), or ara-CMP (cytosine-beta-D-arabinofuranoside 5'-monophosphate), even in the presence of ATP. The activity of ATP-activated IMPase was similar in WI-L2 and CEM cells. dAMPase was separated into two peaks by DEAE-Bio-Gel A chromatography; one of these peaks degraded ara-AMP and ara-CMP. The activities of both peaks from WI-L2 cells were higher than those from CEM cells. These results show that the degradation of dAMP, ara-AMP or ara-CMP was more specific and rapid in WI-L2 than in CEM cells.


Assuntos
Linfócitos B/enzimologia , Nucleotidases/metabolismo , Linfócitos T/enzimologia , 5'-Nucleotidase , Adamantano/análogos & derivados , Adamantano/metabolismo , Adenosina/metabolismo , Linhagem Celular , Cromatografia , Cromatografia em Gel , Citosol/enzimologia , Desoxiadenosinas/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Inosina Monofosfato/metabolismo , Especificidade por Substrato
15.
Clin Exp Rheumatol ; 23(4): 494-8, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16095118

RESUMO

OBJECTIVES: The contribution of the microsatellite polymorphisms of TNFa and TNFb, and the TNFB + 252 (TNFB) dimorphism to the pathogenesis of rheumatoid arthritis (RA) was studied among Japanese patients. METHODS: The TNFa and TNFb microsatellite polymorphisms, and the TNFB dimorphism were determined in Japanese RA patients and normal subjects using electrophoresis followed by specific PCR amplification. HLA-DRB1*04 typing was carried out by the PCR-SSCP method. RESULTS: The allele frequency of TNFa11 showed a significant increase in RA with DRB1*0405 when compared to that in RA without DRB1*0405 (28.5% Vs 12.9%, respectively, p = 0.022). An association analysis indicated that TNFa11 was not primary, but secondary to the increase in HLA-DRB1*0405, because TNFa11 showed a strong positive association with HLA-DRB1*0405 in Japanese controls. The slight increase in the TNFb4 allele observed in RA with DRB1*0405 (50.0%) may be reflective of the increase in TNFa11 and DRB1*0405. In RA with DRB1*0405, the allele frequency of TNFB*2 significantly increased compared to that of normal controls (75.0% Vs 55.3%, respectively, p = 0.007) and compared to that of RA without DRB1*0405 (45.0%, p = 0.001). No significant positive association of TNFB*2 with HLA-DRB1*0405 or TNFa11 in Japanese controls might suggest that the increase in the TNFB*2 allele might not be secondary to the increase in DRB1*0405, and that TNFB*2 might contribute additively to DRB1*0405-positive RA in Japanese. CONCLUSION: TNFB*2 may contribute additively to Japanese RA with HLA-DRB1*0405, while TNFa11 and TNFb4 are not independent genetic markers of RA among Japanese.


Assuntos
Alelos , Artrite Reumatoide/genética , Predisposição Genética para Doença , Linfotoxina-alfa/genética , Repetições de Microssatélites , Fator de Necrose Tumoral alfa/genética , Artrite Reumatoide/etnologia , Feminino , Frequência do Gene , Marcadores Genéticos , Antígenos HLA-DR/análise , Cadeias HLA-DRB1 , Humanos , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Polimorfismo Genético
16.
Mol Immunol ; 33(15): 1171-6, 1996 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9070665

RESUMO

In order to deduce which cellular molecules react with the sera from patients with rheumatoid arthritis (RA), human and mouse cellular extracts were fractionated stepwise, by ethanol precipitation and their reactivity analysed by Western blotting. It was found that three cytoplasmic molecules with molecular weights of 80,000, 81,000 and 77,000 were immunoreactive and they were identified as ezrin (E), radixin (R), and moesin (M), respectively, by partial amino acid sequencing. Using cDNA clones of these human molecules, recombinant proteins were produced in Escherichia coli and used to enable the antigens to detect the antibodies in the sera of patients with RA. Of 71 sera tested, 24 sera (33.8%) reacted with at least one of three recombinant antigens, although there was no significant correlation between the presence of the antibodies and clinical manifestations, such as disease duration or stage. There was also no discernible relationship to other auto-antibodies such as antinuclear antibodies (ANA) and rheumatoid factor. The results suggest that ERM proteins are possible novel auto-immune target antigens for RA.


Assuntos
Artrite Reumatoide/sangue , Artrite Reumatoide/imunologia , Proteínas Sanguíneas/imunologia , Proteínas do Citoesqueleto , Proteínas de Membrana/imunologia , Proteínas dos Microfilamentos , Fosfoproteínas/imunologia , Proteínas/imunologia , Adulto , Idoso , Sequência de Aminoácidos , Reações Antígeno-Anticorpo , Autoantígenos/sangue , Proteínas Sanguíneas/química , Western Blotting , Citoplasma/imunologia , Feminino , Humanos , Masculino , Proteínas de Membrana/química , Pessoa de Meia-Idade , Fosfoproteínas/química , Proteínas/química , Proteínas Recombinantes/imunologia
17.
Annu Int Conf IEEE Eng Med Biol Soc ; 2015: 5760-3, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26737601

RESUMO

This study demonstrates the feasibility of high-gamma activity mapping for localization of somatosensory finger areas in the human brain. Identification of functional brain regions is important in surgical planning, such as for resections of epileptic foci or brain tumors. The mapping procedure is done using electrocorticography (ECoG), an invasive technique in which electrical brain signals are acquired from the cortical surface. Two epilepsy patients with implanted electrode grids participated in the study. Data were collected during a vibrotactile finger stimulation paradigm and showed significant cortical activation (p <; 0.001) in the high-gamma range over the contralateral somatosensory cortex. The results are consistent with previous studies that used fMRI in test subjects without implanted electrodes. Therefore, the results suggest that localizing the cortical representations of the fingers in clinical practice using ECoG is feasible, even without the patient's active participation.


Assuntos
Dedos , Mapeamento Encefálico , Eletrocorticografia , Eletrodos Implantados , Eletroencefalografia , Humanos , Imageamento por Ressonância Magnética , Córtex Somatossensorial
18.
Annu Int Conf IEEE Eng Med Biol Soc ; 2015: 1765-8, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26736620

RESUMO

Intention recognition through decoding brain activity could lead to a powerful and independent Brain-Computer-Interface (BCI) allowing for intuitive control of devices like robots. A common strategy for realizing such a system is the motor imagery (MI) BCI using electroencephalography (EEG). Changing to invasive recordings like electrocorticography (ECoG) allows extracting very robust features and easy introduction of an idle state, which might simplify the mental task and allow the subject to focus on the environment. Especially for multi-channel recordings like ECoG, common spatial patterns (CSP) provide a powerful tool for feature optimization and dimensionality reduction. This work focuses on an invasive and independent MI BCI that allows triggering from an idle state, and therefore facilitates tele-operation of a humanoid robot. The task was to lift a can with the robot's hand. One subject participated and reached 95.4 % mean online accuracy after six runs of 40 trials. To our knowledge, this is the first online experiment with a MI BCI using CSPs from ECoG signals.


Assuntos
Interfaces Cérebro-Computador , Eletrocorticografia , Mãos , Imaginação , Robótica , Idoso , Eletroencefalografia , Desenho de Equipamento , Feminino , Humanos , Modelos Teóricos
19.
FEBS Lett ; 170(1): 139-42, 1984 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-6539251

RESUMO

High tyrosine protein kinase activities were detected in soluble and particulate forms from bone marrow cells using synthetic peptide (Glu-Asp-Ala-Glu-Tyr-Ala-Ala-Arg-Arg-Arg-Gly) as a substrate. Total activity of tyrosine protein kinase was 2.4 times higher in the soluble fraction but the specific activity was slightly higher in the particulate one. Mg2+ or Mn2+ requirements of these two enzymes for maximal activity were quite different from each other. Physiological significance of these two forms of enzymes is briefly discussed.


Assuntos
Medula Óssea/enzimologia , Proteínas Quinases/metabolismo , Animais , Cinética , Magnésio/metabolismo , Masculino , Manganês/metabolismo , Octoxinol , Polietilenoglicóis/farmacologia , Proteínas Tirosina Quinases , Coelhos , Ratos , Ratos Endogâmicos , Distribuição Tecidual
20.
FEBS Lett ; 184(1): 56-9, 1985 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-4039273

RESUMO

Tyrosine protein kinase activities were detected in the cytosolic fraction (PC-TPK) and the particulate fraction (PM-TPK) in human platelets using the synthetic peptide, E11G1 (Glu-Asp-Ala-Glu-Tyr-Ala-Ala-Arg-Arg-Arg-Gly) as a substrate. PC-TPK and PM-TPK were different in substrate specificities, divalent cation requirements and apparent Mr values. These results strongly suggest that in platelets there exist at least two separate tyrosine protein kinases; one is present in cytosol and the other might be associated with membranes.


Assuntos
Plaquetas/enzimologia , Proteínas Quinases/sangue , Citosol/enzimologia , Humanos , Peso Molecular , Proteínas Tirosina Quinases
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