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1.
Mol Ecol ; 22(10): 2683-97, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23611649

RESUMO

Unravelling the genetic history of any livestock species is central to understanding the origin, development and expansion of agricultural societies and economies. Domestic village chickens are widespread in Africa. Their close association with, and reliance on, humans for long-range dispersal makes the species an important biological marker in tracking cultural and trading contacts between human societies and civilizations across time. Archaezoological and linguistic evidence suggest a complex history of arrival and dispersion of the species on the continent, with mitochondrial DNA (mtDNA) D-loop analysis revealing the presence of five distinct haplogroups in East African village chickens. It supports the importance of the region in understanding the history of the species and indirectly of human interactions. Here, through a detailed analysis of 30 autosomal microsatellite markers genotyped in 657 village chickens from four East African countries (Kenya, Uganda, Ethiopia and Sudan), we identify three distinct autosomal gene pools (I, II and III). Gene pool I is predominantly found in Ethiopia and Sudan, while II and III occur in both Kenya and Uganda. A gradient of admixture for gene pools II and III between the Kenyan coast and Uganda's hinterland (P = 0.001) is observed, while gene pool I is clearly separated from the other two. We propose that these three gene pools represent genetic signatures of separate events in the history of the continent that relate to the arrival and dispersal of village chickens and humans across the region. Our results provide new insights on the history of chicken husbandry which has been shaped by terrestrial and maritime contacts between ancient and modern civilizations in Asia and East Africa.


Assuntos
Distribuição Animal , Galinhas/genética , Evolução Cultural , Variação Genética , Genética Populacional , Idioma , África Oriental , Animais , Galinhas/fisiologia , DNA Mitocondrial/genética , Genótipo , Geografia , Haplótipos/genética , Humanos , Repetições de Microssatélites/genética , Modelos Genéticos , Análise de Componente Principal
2.
Mol Phylogenet Evol ; 58(2): 374-82, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21138772

RESUMO

Chicken were possibly domesticated in South and Southeast Asia. They occur ubiquitously in East Africa where they show extensive phenotypic diversity. They appeared in the region relatively late, with the first undisputed evidence of domestic chicken in Sudan, around ~ 700 BC. We reveal through a detailed analysis of mitochondrial DNA D-loop sequence diversity of 512 domestic village chickens, from four East African countries (Kenya, Ethiopia, Sudan, Uganda), the presence of at least five distinct mitochondrial DNA haplogroups. Phylogeographic analyses and inclusion of reference sequences from Asia allow us to address the origin, ways of introduction and dispersion of each haplogroup. The results indicate a likely Indian subcontinent origin for the commonest haplogroup (D) and a maritime introduction for the next commonest one (A) from Southeast and/or East Asia. Recent introgression of commercial haplotypes into the gene pool of village chickens might explain the rare presence of two haplogroups (B and C) while the origin of the last haplogroup (E) remains unclear being currently observed only outside the African continent in the inland Yunnan Province of China. Our findings not only support ancient historical maritime and terrestrial contacts between Asia and East Africa, but also indicate the presence of large maternal genetic diversity in the region which could potentially support genetic improvement programmes.


Assuntos
Galinhas/genética , DNA Mitocondrial/genética , Evolução Molecular , Filogeografia , Animais , Ásia , Etiópia , Pool Gênico , Genética Populacional , Haplótipos , Quênia , Modelos Genéticos , Dinâmica Populacional , Análise de Sequência de DNA , Sudão , Uganda
3.
Acta Psychiatr Scand ; 121(1): 75-7, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19522881

RESUMO

OBJECTIVE: Fahr disease (FD) is a rare neurological and psychiatric disorder. The disease is classified by intracranial calcification of the basal ganglia with the globus pallidus region being particularly affected. We examined a young woman with visual hallucinations, delusions of persecution and a history of performing arson with possible third-generation FD. METHOD: Case report of third-generation FD. RESULTS: A 23-year-old woman was arrested for two arsons: i) The patient exhibited progressive psychotic symptoms, including visual hallucinations, delusion of injury, irritability, lability of mood, mental retardation and visual disorders and ii) Computed tomography (CT) imaging demonstrated bilateral calcifications of the basal ganglia (globus pallidus) in the patient, her mother and her grandmother. CONCLUSION: We found a family with a three-generation history of FD who exhibited calcification in the brain and mental retardation. Compared to her mother, the patient described here displayed anticipation of disease onset.


Assuntos
Doenças dos Gânglios da Base/epidemiologia , Doenças dos Gânglios da Base/genética , Calcinose/diagnóstico , Calcinose/genética , Delusões/epidemiologia , Delusões/genética , Piromania/epidemiologia , Transtornos Psicóticos/epidemiologia , Transtornos Psicóticos/genética , Adulto , Idade de Início , Antecipação Genética/genética , Doenças dos Gânglios da Base/diagnóstico , Calcinose/epidemiologia , Comorbidade , Feminino , Globo Pálido/patologia , Humanos , Deficiência Intelectual/diagnóstico , Deficiência Intelectual/epidemiologia , Deficiência Intelectual/genética , Aplicação da Lei/métodos , Linhagem , Prisioneiros/estatística & dados numéricos , Transtornos Psicóticos/diagnóstico , Síndrome , Tomografia Computadorizada por Raios X/estatística & dados numéricos
4.
Science ; 289(5482): 1188-90, 2000 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-10947985

RESUMO

Pig cloning will have a marked impact on the optimization of meat production and xenotransplantation. To clone pigs from differentiated cells, we microinjected the nuclei of porcine (Sus scrofa) fetal fibroblasts into enucleated oocytes, and development was induced by electroactivation. The transfer of 110 cloned embryos to four surrogate mothers produced an apparently normal female piglet. The clonal provenance of the piglet was indicated by her coat color and confirmed by DNA microsatellite analysis.


Assuntos
Clonagem de Organismos/métodos , Técnicas de Transferência Nuclear , Suínos , Animais , Células Cultivadas , Estimulação Elétrica , Transferência Embrionária , Desenvolvimento Embrionário e Fetal , Feminino , Feto/citologia , Fibroblastos/ultraestrutura , Microinjeções , Repetições de Microssatélites , Oócitos , Gravidez , Suínos/embriologia , Suínos/genética
5.
Anim Genet ; 40(4): 556-9, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19397526

RESUMO

This study describes complete control region sequences of mitochondrial DNA (mtDNA) from 117 Ethiopian cattle from 10 representative populations, in conjunction with the available cattle sequences in GenBank. In total, 79 polymorphic sites were detected, and these defined 81 different haplotypes. The haplotype and nucleotide diversity of Ethiopian cattle did not vary among the populations studied. All mtDNA sequences from Ethiopian cattle converged into one main maternal lineage (T1) that corresponds to African Bos taurus cattle. According to the results of this study, no zebu mtDNA haplotypes have been found in Ethiopia, where the most extensive hybridization took place on the African continent.


Assuntos
Bovinos/genética , DNA Mitocondrial/química , Polimorfismo Genético , Animais , Etiópia , Feminino , Haplótipos , Dados de Sequência Molecular , Filogenia , Análise de Sequência de DNA
6.
Anim Genet ; 39(4): 425-31, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18565163

RESUMO

Ethiopian cattle are under threat from uncontrolled mating practices and are at high risk of becoming genetically homogeneous. Therefore, to evaluate genetic diversity, population structure and degree of admixture, 30 microsatellite markers were genotyped using 351 DNA samples from 10 Ethiopian cattle populations and the Holstein breed. The mean number of alleles per cattle population ranged from 6.93 +/- 2.12 in Sheko to 7.50 +/- 2.35 in Adwa. The mean observed and expected heterozygosities were 0.674 +/- 0.015 and 0.726 +/- 0.019 respectively. Ethiopian cattle populations have maintained a high level of within-population genetic differentiation (98.7%), the remainder being accounted for by differentiation among populations (1.3%). A highly significant deficiency in heterozygotes was detected within populations (F(IS) = 0.071; P < 0.001) and total inbreeding (F(IT) = 0.083; P < 0.001). The study populations were highly admixed but distinct from pure Bos taurus and Bos indicus breeds. The various levels of admixture and high genetic diversity make Ethiopian cattle populations suitable for future genetic improvement and utilization under a wide range of agro-ecologies in Ethiopia.


Assuntos
Bovinos/genética , Variação Genética , Genética Populacional , Repetições de Microssatélites , Alelos , Animais , Etiópia , Fluxo Gênico , Marcadores Genéticos , Genótipo , Endogamia , Filogenia
7.
J Hum Hypertens ; 21(11): 883-92, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17525706

RESUMO

Endothelin-1 (ET-1) is a potent vasoconstrictive peptide and its activity is mediated by the receptors ET type A (EDNRA) and ET type B (EDNRB). Although ET-1 is thought to play an important role in the development of atherosclerosis, it remains unclear whether polymorphisms of ET-1 family genes, including the ET-1 gene (EDN1), EDNRA, EDNRB and the genes for endothelin converting enzymes 1 and 2 (ECE1 and ECE2), are associated with the progression of atherosclerosis. We investigated the relationship between 11 single nucleotide polymorphisms (SNPs) of ET-1 family genes (including three in EDN1, one in EDNRA, two in EDNRB, four in ECE1 and one in ECE2) and atherosclerotic changes assessed using pulse wave velocity (PWV) and carotid ultrasonography in 630 patients with essential hypertension (EHT). In male subjects, we found significant differences in brachial-ankle PWV (baPWV) in additive and recessive models in EDNRB-rs5351 after Bonferroni correction. Also in male subjects, there were significant differences in mean intima-media thickness (IMT) in additive and recessive models in EDNRA-rs5333 after Bonferroni correction. We found no significant correlation between any SNPs in the ET family genes and baPWV, IMT and Plaque score (PS) in female subjects. Furthermore, after multiple logistic regression analysis, only EDNRB-rs5351 indicated as an independent risk of atherosclerosis in male hypertensive subjects. Of the endothelin-related genes, EDNRB-rs5351 was the most susceptible SNP associated with atherosclerosis in male hypertensives, and the genetic background may be involved in the progression of atherosclerosis in EHT patients.


Assuntos
Aterosclerose/genética , Hipertensão/genética , Polimorfismo de Nucleotídeo Único , Receptor de Endotelina B/genética , Adulto , Idoso , Progressão da Doença , Endotelina-1/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fluxo Pulsátil , Receptor de Endotelina A/genética , Túnica Íntima/patologia , Túnica Média/patologia
8.
J Am Coll Cardiol ; 36(6): 1847-52, 2000 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-11092655

RESUMO

OBJECTIVES: We measured phospholipase C (PLC) activity in the cultured skin fibroblasts obtained from patients with and without coronary spasm and examined its correlation with coronary artery vasomotility. BACKGROUND: Coronary artery vasomotility is enhanced in coronary spastic angina (CSA), but no information is available for the intracellular signaling. In spontaneously hypertensive rats, PLC activity in the skin fibroblasts has been shown to be enhanced. METHODS: Skin fibroblasts obtained from 24 patients with CSA-14 with organic coronary artery disease (CAD) and 12 control subjects--were cultured by the explant method. Activity of PLC was determined by incubating the membrane fraction with 3H-phosphatidyl inositol bisphosphate and by quantifying 3H-inositol trisphosphate. In patients with CSA and control subjects, the relations between PLC activity and coronary artery basal tone and constrictor response to intracoronary acetylcholine (ACh) were examined. RESULTS: Activity of PLC (pmol/protein [mg] per min) was 1.74+/-0.19 in patients with CSA; 0.90+/-0.12 in patients with CAD; and 0.65+/-0.07 in control subjects (p<0.001, patients with CSA vs. patients with CAD and control subjects; p = NS, patients with CAD vs. control subjects). According to the Lineweaver-Burk plot, Michaelis constant (micromol/liter) of PLC was 28+/-4 in patients with CSA; 49+/-14 in patients with CAD; and 56+/-10 in control subjects (p<0.05, patients with CSA vs. control subjects), whereas the maximal velocity was not different between the three groups. There were significant positive correlations between PLC activity and both basal tone (p = 0.0108) and response to ACh (p = 0.0053). Western blot analysis using membrane fraction demonstrated that 89% of PLC isoenzymes detected was of the delta1 isoform. CONCLUSIONS: Because the PLC activity measured was genetically defined and was positively correlated with coronary artery vasomotility, enhanced PLC activity may be involved in the pathogenesis of coronary spasm.


Assuntos
Angina Pectoris Variante/fisiopatologia , Vasos Coronários/fisiopatologia , Fibroblastos/metabolismo , Pele/citologia , Fosfolipases Tipo C/metabolismo , Vasoconstrição , Angina Pectoris Variante/sangue , Células Cultivadas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
9.
Genetics ; 155(2): 777-83, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10835398

RESUMO

To investigate the interactions between mtDNA and nuclear genomes, we produced heteroplasmic maternal lineages by transferring the cytoplasts between the embryos of two mouse strains, C57BL/6 (B6) and RR. A total of 43 different nucleotides exist in the displacement-loop (D-loop) region of mtDNA between B6 and RR. Heteroplasmic embryos were reconstructed by electrofusion using a blastomere from a two-cell stage embryo of one strain and an enucleated blastomere from a two-cell stage embryo of the other strain. Equivalent volumes of both types of mtDNAs were detected in blastocyst stage embryos. However, the mtDNA from the RR strain became biased in the progeny, regardless of the source of the nuclear genome. The RR mtDNA population was very high in most of the tissues examined but was relatively low in the brain and the heart. An age-related increase of RR mtDNA was also observed in the blood. The RR mtDNAs in the reconstructed embryos and in the embryos collected from heteroplasmic mice showed a different segregation pattern during early embryonic development. These results suggest that the RR mtDNA has a replicative advantage over B6 mtDNA during embryonic development and differentiation, regardless of the type of nuclear genome.


Assuntos
DNA Mitocondrial/genética , Animais , Sequência de Bases , Blastômeros , Clonagem Molecular , Camundongos , Camundongos Endogâmicos C57BL , Dados de Sequência Molecular , Especificidade da Espécie
10.
FEBS Lett ; 257(2): 465-7, 1989 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-2531096

RESUMO

We prepared two types of E. coli F1 by slightly different gel filtration procedures of the purified F1: F1(II) contained about 2 mol, and F1(V) about 5 mol of bound adenine nucleotides per mol of the enzyme. Thus F1(II) had more than 2, possibly 3, vacant catalytic sites, while F1(V) had less than one vacant catalytic site. The rate of ATP hydrolysis in uni-site catalysis (in the presence of inorganic phosphate) was about 3-fold higher with F1(II) than with F1(V), suggesting that ADP and inorganic phosphate bound at the catalytic sites of F1(V) changed the kinetics of uni-site catalysis significantly.


Assuntos
Nucleotídeos de Adenina/metabolismo , Escherichia coli/enzimologia , ATPases Translocadoras de Prótons/metabolismo , Sítios de Ligação , Cinética , ATPases Translocadoras de Prótons/isolamento & purificação
11.
FEBS Lett ; 355(1): 65-8, 1994 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-7957965

RESUMO

We have investigated the distribution of the sarcolemmal Ca2+ transporters in hamster and dog ventricular myocytes by immunocytochemical and membrane fractionation techniques. The data suggest that the DHP receptor alpha 1 subunit and the Na+/Ca2+ exchanger are present in surface sarcolemma as well as T-tubule membranes located at the cardiac dyads. Compared with these Ca2+ transporters, the sarcolemmal Ca(2+)-ATPase is much less abundant in the latter fraction. Thus the sarcolemmal Ca(2+)-ATPase seems to be located predominantly in surface sarcolemma.


Assuntos
ATPases Transportadoras de Cálcio/análise , Proteínas de Transporte/análise , Proteínas Musculares/análise , Miocárdio/química , Sarcolema/química , Animais , Canais de Cálcio Tipo L , Cricetinae , Cães , Immunoblotting , Microscopia de Fluorescência , Microssomos/química , Microssomos/enzimologia , Miocárdio/enzimologia , Sarcolema/enzimologia , Trocador de Sódio e Cálcio
12.
FEBS Lett ; 423(2): 173-7, 1998 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-9512352

RESUMO

Overlay and co-sedimentation assays using recombinant alpha1-syntrophin proteins revealed that two regions of alpha1-syntrophin, i.e. aa 274-315 and 449-505, contain high-affinity binding sites for F-actin (Kd 0.16-0.45 microM), although only a single high-affinity site (Kd 0.35 microM) was detected in the recombinant full-length syntrophin. We also found that actomyosin fractions prepared from both cardiac and skeletal muscle contain proteins recognized by anti-syntrophin antibody. These data suggest a novel role for syntrophin as an actin binding protein, which may be important for the function of the dystrophin-glycoprotein complex or for other cell functions. We also found that alpha1-syntrophin binds calmodulin at two distinct sites with high (Kd 15 nM) and low (Kd 0.3 microM) affinity.


Assuntos
Actinas/metabolismo , Calmodulina/metabolismo , Proteínas de Membrana/metabolismo , Proteínas Musculares/metabolismo , Proteínas Recombinantes de Fusão/metabolismo , Actomiosina/isolamento & purificação , Animais , Sítios de Ligação , Ligação Competitiva , Proteínas de Ligação ao Cálcio , Cricetinae , Distrofina/fisiologia , Proteínas de Membrana/química , Proteínas Musculares/química , Coelhos
13.
Free Radic Biol Med ; 23(2): 294-301, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9199892

RESUMO

Although "programmed cell death" has been postulated to underlie the mechanism for the disappearance of the tadpole tail, critical factors that trigger this phenomenon remain to be elucidated. To investigate the mechanism for the disappearance of the tail, changes in morphology, DNA status and the enzymes which metabolize reactive oxygen species were determined in the tail of Rana rugosa tadpoles. Histological examination revealed that apoptotic cell death was apparent in the tail myocytes during metamorphosis. Electrophoretic analysis of the tail DNA revealed a marked fragmentation. During the apoptotic changes, the activity of Cu/Zn-type superoxide dismutase (SOD) in the tail markedly increased with a concomitant decrease in its catalase activity. The apoptotic process was markedly enhanced by adding hydrogen peroxide (H2O2) and aminotriazole, a catalase inhibitor, to the medium. These observations suggested that apoptotic cell death in the tadpole tail might be triggered, at least in part, by a mechanism depending on active oxygen species, such as H2O2.


Assuntos
Apoptose/fisiologia , Ranidae/crescimento & desenvolvimento , Ranidae/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Cauda/citologia , Cauda/metabolismo , Amitrol (Herbicida)/toxicidade , Animais , Catalase/metabolismo , Fragmentação do DNA , Radicais Livres/metabolismo , Peróxido de Hidrogênio/toxicidade , Larva/citologia , Larva/crescimento & desenvolvimento , Larva/metabolismo , Metamorfose Biológica/efeitos dos fármacos , Superóxido Dismutase/metabolismo , Cauda/crescimento & desenvolvimento
14.
Free Radic Biol Med ; 26(7-8): 1001-9, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10232845

RESUMO

Our objective is to clarify the role of reactive oxygen species (ROS) in the atrophying tail of anuran tadpoles (tail apoptosis). Changes in catalase, superoxide dismutase (SOD) and caspase activity, genomic DNA, and nitric oxide (NO) generation were investigated biochemically using Rana japonica tadpole tails undergoing regression during thyroid hormone enhancement. DNA fragmentation and ladder formation with concomitant shortening of tadpole tail were induced by DL-thyroxine (T4) in culture medium. Catalase activity was also decreased by T4 treatment. T4 was also found to increase NO synthase (NOS) activity in cultured tadpole tail with concomitant increase in the concentration of NO2- plus NO3- (NOx) in the culture medium. Additional treatment with N-monomethyl-L-arginine (NMMA), a potent inhibitor of NOS, suppressed the enhancing effects of T4 on tail shortening and catalase activity reduction. It was also found that treatment with isosorbide dinitrate (ISDN), a NO generating drug, alone also had an enhancing effect on tail shortening and catalase activity reduction similar to that seen with T4. Both NO and an NO donor (ISDN) strongly suppressed catalase activity. Kinetic analysis revealed that catalase activity decreased and caspase-3-like activity increased during normal tadpole tail atrophy (apoptosis). These results suggested that T4 enhances NO generation, thereby strongly inhibiting catalase activity, resulting in an increase in hydrogen peroxide, and that the oxidative stress elicited by excess hydrogen peroxide might activate cysteine-dependent aspartate-directed protease-3 (caspase-3-like protease), which is thought to cause DNA fragmentation, leading to apoptosis.


Assuntos
Apoptose/fisiologia , Catalase/metabolismo , Espécies Reativas de Oxigênio/fisiologia , Superóxido Dismutase/metabolismo , Tiroxina/farmacologia , Animais , Apoptose/efeitos dos fármacos , Caspases/metabolismo , Fragmentação do DNA , Peróxido de Hidrogênio/metabolismo , Cinética , Larva , Óxido Nítrico/metabolismo , Técnicas de Cultura de Órgãos , Ranidae , Cauda , Fatores de Tempo , ômega-N-Metilarginina/farmacologia
15.
Am J Cardiol ; 70(20): 1583-8, 1992 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-1466327

RESUMO

In patients with hypertrophic cardiomyopathy (HC), it is difficult to determine the severity of left ventricular (LV) diastolic dysfunction. Three different patterns of LV posterior wall motion were found by M-mode echocardiography in patients with HC, and the use of these patterns is proposed as a new noninvasive index of the severity of LV diastolic dysfunction. M-mode echocardiograms were recorded prospectively from 35 patients with HC, and the posterior wall motion pattern in late systole and early diastole was classified into the following 3 types: (1) normal motion (n = 9); (2) flat motion--flat motion from late systole to early diastole, followed by rapid backward movement (n = 13); and (3) downward motion--slow backward movement from late systole (n = 13). There were no differences in the severity or type of hypertrophy, LV systolic function and pulsed Doppler indexes of LV filling among these 3 groups. However, LV end-diastolic pressure was increased in the groups with flat (15 +/- 6 mm Hg) and downward (16 +/- 9 mm Hg) motion. Furthermore, the maximal rate of decrease in LV pressure (normal 1,450 +/- 300, flat 1,250 +/- 300 and downward 860 +/- 80 mm Hg/s) and the time constant of LV pressure reduction (normal 60 +/- 15, flat 70 +/- 25 and downward 101 +/- 34 ms) showed a stepwise deterioration from the normal to the flat and then to the downward motion groups.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Cardiomiopatia Hipertrófica/diagnóstico por imagem , Ecocardiografia , Contração Miocárdica/fisiologia , Função Ventricular Esquerda/fisiologia , Angiotensina II , Cateterismo Cardíaco , Cardiomiopatia Hipertrófica/fisiopatologia , Ecocardiografia Doppler , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
16.
Chest ; 113(2): 306-11, 1998 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9498943

RESUMO

STUDY OBJECTIVES: Sinus node deceleration during exercise is a highly specific marker for significant stenosis of the right coronary artery. Prior studies of dobutamine-induced sinus node deceleration have contained relatively few patients, and the purpose of this study was to determine if sinus node deceleration is an accurate marker of right coronary artery disease in a much larger study population. DESIGN: Dobutamine stress echocardiography was performed in a cohort of patients, and submaximal exercise testing and coronary angiography were performed in most of the patients. SETTING: A university hospital. PATIENTS AND INTERVENTIONS: Dobutamine stress echocardiography was performed in 757 patients, and symptom-limited submaximal treadmill ECG was also performed in 571 of those patients. Sinus node deceleration was defined as a decrease in the heart rate at peak stress compared with that at the previous stage. Coronary angiography was performed in 631 patients, 184 of whom were found to have significant right coronary artery stenosis. MEASUREMENTS AND RESULTS: The prevalence of dobutamine-induced sinus node deceleration (54 [7%] of 757 patients) was significantly higher than that induced during treadmill ECG (3 [0.5%] of 571 patients; p<0.001). The prevalence of inferior ischemia by echocardiography did not differ between patients with dobutamine-induced sinus node deceleration (26%) and those without (30%). There was also no significant difference in the prevalence of right coronary artery stenosis between the two groups (27% vs 29%). The specificity of dobutamine-induced sinus node deceleration for detecting significant stenosis of the right coronary artery (92%) was higher than that of echocardiography (84%; p<0.00), but the positive predictive value was lower (28% vs 64%; p<0.001). CONCLUSIONS: Although sinus node deceleration during dobutamine stress echocardiography is a relatively more common finding, it does not always accompany significant stenosis in the right coronary artery. The mechanism for its induction is postulated to be vagal activation caused by multiple factors.


Assuntos
Agonistas Adrenérgicos beta , Doença das Coronárias/diagnóstico , Dobutamina , Nó Sinoatrial/efeitos dos fármacos , Distribuição de Qui-Quadrado , Estudos de Coortes , Angiografia Coronária , Doença das Coronárias/diagnóstico por imagem , Doença das Coronárias/fisiopatologia , Ecocardiografia , Eletrocardiografia , Teste de Esforço , Feminino , Frequência Cardíaca/efeitos dos fármacos , Frequência Cardíaca/fisiologia , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Isquemia Miocárdica/diagnóstico , Isquemia Miocárdica/fisiopatologia , Valor Preditivo dos Testes , Prevalência , Sensibilidade e Especificidade , Estresse Fisiológico/fisiopatologia , Nervo Vago/fisiopatologia
17.
J Biochem ; 114(4): 528-34, 1993 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8276763

RESUMO

The amino acid sequences of two isoforms of the rat aortic smooth muscle Na+/Ca2+ exchanger have been deduced by cloning and sequencing the cDNAs. These isoforms are identical in nucleotide sequence except that one has a 23-amino acid insertion at amino acid position 570. They are highly homologous to the canine cardiac exchanger except for the NH2-terminal portion and part of the large central hydrophilic domain (amino acid residues 570-631). They are 902 and 925 (with the insertion) amino acid long with calculated molecular masses of 100,676 and 103,200 (with the insertion), respectively, if the NH2-terminal 32-amino acid residues are eliminated as a cleaved signal sequence. Amplification of the variable region (amino acids 570-631) of the exchanger by means of the reverse transcriptase-polymerase chain reaction and DNA sequencing revealed that many isoforms of the exchanger are expressed in different rat tissues. The two clones isolated in this study are the predominant isoforms expressed in aorta, stomach, liver, and kidney. In cardiac and skeletal muscles, another isoform is dominant, which is equivalent to the canine cardiac exchanger. In brain, a third type is predominantly expressed. Alignment of the nucleotide sequences of these isoforms and Southern blot analysis of rat genomic DNA suggested that each isoform is generated through alternative splicing of the primary transcript.


Assuntos
Proteínas de Transporte/genética , Clonagem Molecular , Expressão Gênica , Músculo Liso Vascular/química , Processamento Alternativo , Sequência de Aminoácidos , Animais , Aorta/química , Sequência de Bases , Southern Blotting , Proteínas de Transporte/química , Células Cultivadas , Cães , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Especificidade de Órgãos , Reação em Cadeia da Polimerase , Ratos , Homologia de Sequência do Ácido Nucleico , Trocador de Sódio e Cálcio
18.
Metabolism ; 51(10): 1247-52, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12370842

RESUMO

The purpose of the present study was to investigate the relationships among the resting systolic (SBP) and diastolic blood pressure (DBP) or SBP response during exercise with insulin resistance evaluated by a homeostasis model (HOMA-IR), abdominal fat accumulation (visceral fat area [VFA], subcutaneous fat area [SFA]) by computed tomography (CT), and an estimation of the maximal oxygen uptake (V*O2max) in 63 Japanese middle-aged male patients with type 2 diabetes mellitus (type 2 DM). Body mass index (BMI) and waist-to-hip ratio (WHR) in type 2 DM subjects were significantly higher than in age-matched healthy male control subjects (n = 135) with normal glucose tolerance. Resting SBP (127.7 +/- 16.2 mm Hg v 119.4 +/- 13.0 mm Hg) and DBP (82.2 +/- 11.9mmHg v 76.8 +/- 9.4 mm Hg) levels, and the percentage of hypertension (20.6% v 1.5%) in type 2 DM subjects were significantly higher than in the control subjects (P <.05). According to a multiple regression analysis for resting blood pressure in type 2 DM, VFA was found to be an independent predictor of SBP, while V*O2max and HOMA-IR were independent predictors of DBP. In the controls, however, HOMA-IR was not found to be a significantly independent predictor for either resting SBP or resting DBP. Measurement of the SBP response during graded exercise using a ramp test was performed by an electrical braked cycle ergometer in 54 patients with type 2 DM only. The SBP was measured at 15-second intervals during exercise. The exercise intensity at the double product breaking point (DPBP), which strongly correlated with the exercise intensity at the lactate threshold, was used as an index for the SBP response to standardized exercise intensity. The SBP corresponding to exercise intensity at DPBP (SBP@DPBP) was evaluated as an index of the SBP response to standardized exercise intensity. The change in SBP (deltaSBP = SBP@DPBP - resting SBP) was significantly and positively associated with log area under the curve for glucose (log AUCPG) during a 75-g oral glucose tolerance test (OGTT). In addition, deltaSBP significantly and negatively correlated with the log area under the curve for insulin (log AUCIRI) and log AUCIRI/log AUCPG. Based on these results, insulin resistance was suggested to be independently associated with the resting DBP and SBP response to standardized exercise intensity in type 2 DM patients.


Assuntos
Pressão Sanguínea/fisiologia , Diabetes Mellitus Tipo 2/fisiopatologia , Diabetes Mellitus/fisiopatologia , Exercício Físico/fisiologia , Resistência à Insulina/fisiologia , Obesidade , Resistência Física/fisiologia , Aptidão Física/fisiologia , Antropometria , Índice de Massa Corporal , Diabetes Mellitus Tipo 2/terapia , Teste de Tolerância a Glucose , Humanos , Masculino , Pessoa de Meia-Idade , Consumo de Oxigênio/fisiologia , Descanso/fisiologia
19.
J Gastroenterol ; 30(3): 347-50, 1995 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7544188

RESUMO

The correlation between serum hepatitis C virus (HCV)-RNA and aminotransferase levels following completion of interferon therapy was evaluated in eight relapsed patients with chronic hepatitis C. Both HCV-RNA and aminotransferase levels were significantly increased in the relapsed patients 1 month after completion of therapy, compared to pretreatment values, despite aminotransferase levels being normal and HCV-RNA being undetectable by reverse transcription polymerase chain reaction assay at the end of therapy. The serum levels of HCV-RNA and aminotransferase were significantly elevated 1 and 2 months post-treatment. They then decreased to pretreatment values 3-5 months after the completion of therapy. Thus, in relapsed patients after the completion of therapy, the changes in HCV-RNA levels preceded the elevation in aminotransferase levels. These findings suggest a correlation between serum HCV-RNA levels and aminotransferase levels in relapsed patients with chronic hepatitis C after the completion of interferon therapy.


Assuntos
Hepacivirus/genética , Hepatite C/terapia , Hepatite Crônica/terapia , Interferons/uso terapêutico , RNA Viral/análise , Transaminases/metabolismo , Viremia/terapia , Adulto , Feminino , Hepatite C/enzimologia , Hepatite C/fisiopatologia , Hepatite Crônica/enzimologia , Hepatite Crônica/fisiopatologia , Humanos , Interferons/administração & dosagem , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Prognóstico , Recidiva , Análise de Regressão , Viremia/enzimologia , Viremia/fisiopatologia
20.
Diabetes Res Clin Pract ; 25(3): 191-8, 1994 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7851274

RESUMO

To investigate whether a resistance to insulin-stimulated glucose uptake (IR) is associated with the risk factors (RF) for cardiovascular disease (CVD) in non-insulin-dependent diabetic (NIDDM) patients, we determined the degree of IR in 135 adult NIDDM patients who had no advanced diabetic complications. The euglycemic (80 mg/dl) hyperinsulinemic clamp (insulin infusion rate 1.12 mU/kg per min) was performed and the average glucose infusion rate (GIR) during a steady-state euglycemia was determined as a measure of IR. Hypertension was more common among NIDDM patients with an increased IR and was highest in the group of patients with CVD. CVD-RF such as hypertension, hypertriglyceridemia, low HDL-cholesterol and obesity tended to cluster in the NIDDM patients who had lower GIR values and higher fasting IRI levels. GIR values were compared between a set of groups extracted from the 135 NIDDM patients that were matched for age, sex, body mass index and HbA1c levels. The CVD-positive group had the significantly lower GIR value than the CVD-negative group (2.06 +/- 0.66 vs. 3.45 +/- 1.75, P < 0.005). The GIR value was also significantly lower in the hypertriglyceridemic group compared with the normotriglyceridemic group (2.50 +/- 1.36 vs. 4.03 +/- 1.82, P < 0.0005). However, there was no significant difference between the hypertensive and normotensive groups and between the high cholesterol or low HDL-cholesterol groups and their respective control groups. In conclusion, these results suggest that IR contributes to the clustering of CVD-RFs which may accelerate the development of CVD in the subgroup of Japanese NIDDM patients.


Assuntos
Doenças Cardiovasculares/epidemiologia , Diabetes Mellitus Tipo 2/fisiopatologia , Diabetes Mellitus/epidemiologia , Angiopatias Diabéticas/epidemiologia , Resistência à Insulina , Obesidade , Adulto , Idoso , Apolipoproteínas/sangue , Colesterol/sangue , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Diabetes Mellitus Tipo 2/sangue , Feminino , Humanos , Hipertensão/epidemiologia , Insulina/sangue , Japão/epidemiologia , Lipoproteínas VLDL/sangue , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Triglicerídeos/sangue
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