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1.
Endocrinology ; 114(6): 2210-5, 1984 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-6373240

RESUMO

A neutral protease with angiotensin I-forming activity which could readily be separated from acid proteases and plasma and renal renin was obtained from extracts of dog brain. This enzyme has an apparent mol wt of 40,000 by Sephadex chromatography. On chromatofocusing, it displays isoelectric points of 7.92, 7.73, and 7.42, and thus, it is a basic protein, in contrast to either renal or plasma renin which are acidic proteins. This brain enzyme does not react with antibodies specific for dog kidney renin. Since the brain enzyme forms angiotensin I from renin substrate at neutral pH, yet can be separated from and has isoelectric points different from renal renin, it is an isoenzyme of the kidney counterpart. The majority of the renin-like activity of dog brain is due to this isoenzyme.


Assuntos
Encéfalo/enzimologia , Endopeptidases/metabolismo , Animais , Complexo Antígeno-Anticorpo , Cromatografia de Afinidade/métodos , Cromatografia em Gel/métodos , Reações Cruzadas , Cães , Endopeptidases/isolamento & purificação , Feminino , Soros Imunes , Rim/enzimologia , Masculino , Nefrectomia , Especificidade de Órgãos , Renina/metabolismo
2.
Rofo ; 184(10): 975-82, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23897531

RESUMO

PURPOSE: To evaluate how accurately final infarct volume in acute ischemic stroke can be predicted with perfusion CT (PCT) using a 64-MDCT unit and the toggling table technique. MATERIALS AND METHODS: Retrospective analysis of 89 patients with acute ischemic stroke who underwent CCT, CT angiography (CTA) and PCT using the "toggling table" technique within the first three hours after symptom onset. In patients with successful thrombolytic therapy (n = 48) and in those without effective thrombolytic therapy (n = 41), the infarct volume and the volume of the penumbra on PCT were compared to the infarct size on follow-up images (CT or MRI) performed within 8 days. The feasibility of complete infarct volume prediction by 8 cm cranio-caudal coverage was evaluated. RESULTS: The correlation between the volume of hypoperfusion on PCT defined by cerebral blood volume reduction and final infarct volume was strongest in patients with successful thrombolytic therapy with underestimation of the definite infarct volume by 8.5 ml on average. The CBV map had the greatest prognostic value. In patients without successful thrombolytic therapy, the final infarct volume was overestimated by 12.1 ml compared to the MTT map on PCT. All infarcts were detected completely. There were no false-positive or false-negative results. CONCLUSION: Using PCT and the "toggling table" technique in acute stroke patients is helpful for the rapid and accurate quantification of the minimal final infarct and is therefore a prognostic parameter which has to be evaluated in further studies to assess its impact on therapeutic decision. KEY POINTS: ▶ Using PCT and the "toggling table technique" allows accurate quantification of the infarct core and penumbra. ▶ It is possible to record dynamic perfusion parameters quickly and easily of almost the entire supratentorial brain volume on a 64-slice MDCT unit. ▶ The technique allows identification of those patients who could profit from thrombolytic therapy outside the established time intervals.


Assuntos
Angiografia Cerebral/métodos , Infarto Cerebral/diagnóstico , Interpretação de Imagem Assistida por Computador/métodos , Tomografia Computadorizada Multidetectores/métodos , Imagem de Perfusão/métodos , Idoso , Idoso de 80 Anos ou mais , Volume Sanguíneo/efeitos dos fármacos , Encéfalo/irrigação sanguínea , Infarto Cerebral/tratamento farmacológico , Meios de Contraste , Imagem de Difusão por Ressonância Magnética/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Sensibilidade e Especificidade , Terapia Trombolítica/métodos , Ultrassonografia Doppler Transcraniana
3.
Rofo ; 185(10): 975-82, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24490233

RESUMO

PURPOSE: To evaluate how accurately final infarct volume in acute ischemic stroke can be predicted with perfusion CT (PCT) using a 64-MDCT unit and the toggling table technique. MATERIALS AND METHODS: Retrospective analysis of 89 patients with acute ischemic stroke who underwent CCT, CT angiography (CTA) and PCT using the "toggling table" technique within the first three hours after symptom onset. In patients with successful thrombolytic therapy (n = 48) and in those without effective thrombolytic therapy (n = 41), the infarct volume and the volume of the penumbra on PCT were compared to the infarct size on follow-up images (CT or MRI) performed within 8 days. The feasibility of complete infarct volume prediction by 8 cm cranio-caudal coverage was evaluated. RESULTS: The correlation between the volume of hypoperfusion on PCT defined by cerebral blood volume reduction and final infarct volume was strongest in patients with successful thrombolytic therapy with underestimation of the definite infarct volume by 8.5 ml on average. The CBV map had the greatest prognostic value. In patients without successful thrombolytic therapy, the final infarct volume was overestimated by 12.1 ml compared to the MTT map on PCT. All infarcts were detected completely. There were no false-positive or false-negative results. CONCLUSION: Using PCT and the "toggling table" technique in acute stroke patients is helpful for the rapid and accurate quantification of the minimal final infarct and is therefore a prognostic parameter which has to be evaluated in further studies to assess its impact on therapeutic decision.


Assuntos
Infarto Cerebral/diagnóstico por imagem , Interpretação de Imagem Assistida por Computador/métodos , Tomografia Computadorizada Multidetectores/instrumentação , Tomografia Computadorizada Multidetectores/métodos , Posicionamento do Paciente/instrumentação , Posicionamento do Paciente/métodos , Imagem de Perfusão/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Volume Sanguíneo/fisiologia , Encéfalo/irrigação sanguínea , Angiografia Cerebral/métodos , Infarto Cerebral/tratamento farmacológico , Estudos de Viabilidade , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Fluxo Sanguíneo Regional/fisiologia , Terapia Trombolítica , Resultado do Tratamento
4.
Phys Rev Lett ; 75(11): 2144-2147, 1995 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-10059225
6.
Phys Rev B Condens Matter ; 51(15): 10057-10067, 1995 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-9977682
7.
Plant Mol Biol ; 35(5): 661-6, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9349287

RESUMO

Maturing citrus fruit undergo pigment changes which can be enhanced by exogenous ethylene. In order to identify genes induced by ethylene in citrus fruit peel, we cloned the gene c-thi1. mRNA corresponding to c-thi1 increased gradually in the peel during natural fruit maturation and in response to ethylene. GA3 pretreatment reduced the inductive effect of ethylene. Levels of c-thi1 increased also in juice sacs but the effect of ethylene was much less prominent. c-thi1 is homologous to yeast and plant genes encoding for an enzyme belonging to the pathway of thiamine biosynthesis. The data suggest that thiamine is involved in citrus fruit maturation.


Assuntos
Proteínas de Arabidopsis , Citrus/genética , Proteínas de Ligação a DNA/genética , Etilenos/farmacologia , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Reguladores de Crescimento de Plantas/farmacologia , Tiamina/biossíntese , Fatores de Transcrição/genética , Adenina/análogos & derivados , Adenina/farmacologia , Sequência de Aminoácidos , Compostos de Benzil , Citrus/crescimento & desenvolvimento , Clonagem Molecular , Regulação da Expressão Gênica de Plantas/genética , Genes de Plantas/genética , Giberelinas/farmacologia , Cinetina , Dados de Sequência Molecular , Plantas/genética , Purinas , RNA Mensageiro/análise , RNA de Plantas/análise , Homologia de Sequência de Aminoácidos , Leveduras/genética
8.
Rehabilitation (Stuttg) ; 26(1): 11-9, 1987 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-3563090

RESUMO

At the beginning and at the end of inpatient cardiac rehabilitation, 105 male cardiac patients were examined with a newly designed questionnaire for life satisfaction assessment (Fragebogen zur Lebenszufriedenheit-FLZ). Data collection moreover included the Freiburg Personality Inventory, the Freiburg Somatic Complaints Lists, an adjective list assessing current mood, questionnaires on anamnestic data, treatment expectancies and life habits, as well as medical data. Significant correlations found between the FLZ and subjective or objective criteria of rehabilitation outcome indicate the importance of life satisfaction, with more content patients showing better outcomes. No mean value differences were found in respect of medical data, less content patients, however, reported more previous hospital stays and rehabilitation treatments. Also, there is a tendency for physician to discharge these patients as "unfit for work". 83 of these 105 patients participated in the follow-up study twelve months later. Life satisfaction is now lower, somatic complaints and emotional lability have increased. 90 percent of the patients with high life satisfaction, but only 66 percent of those with low life satisfaction, are back at work on follow-up. Fitness for work at follow-up, though primarily related to the rating given at the end of inpatient cardiac rehabilitation, is influenced to a high degree by non-medical factors. The results obtained underline the significance of patient illness behaviour, and point to a need for further improving individual psychological counseling during cardiac rehabilitation.


Assuntos
Reabilitação Cardíaca , Satisfação Pessoal , Qualidade de Vida , Doenças Cardiovasculares/psicologia , Terapia Combinada , Doença das Coronárias/reabilitação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/reabilitação , Prognóstico , Papel do Doente
9.
Plant J ; 20(6): 653-61, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10652137

RESUMO

We report on the isolation, functional expression and characterization of a cDNA encoding chlorophyllase, the enzyme catalyzing the first step in the chlorophyll breakdown pathway. The Chlase1 cDNA from Valencia Orange (Citrus sinensis cv. Valencia) was obtained by RT-PCR using degenerate primers based on the amino acid sequence of the previously purified protein. Chlase1 encodes a protein of 329 amino acids, including a sequence domain characterizing serine-lipases and a putative chloroplast-directing transit peptide. The Chlase1 gene encodes an active chlorophyllase enzyme which catalyzes the dephytylation of chlorophyll as shown by in vitro recombinant enzyme assays. Chlorophyllase expression at the transcript level in Valencia orange peel was found to be low and constitutive during natural fruit development without significant increase towards color-break and ripening. However, ethylene treatment induced an increase in chlorophyllase transcript at all stages of development. An enhanced response to ethylene treatment was observed during the months of October and November, corresponding to the time of natural color-break. The senescence-delaying regulator gibberellin-A3 (GA3) inhibited the effect of ethylene on chlorophyllase transcript accumulation. The data presented suggest that chlorophyllase may not be the regulator of chlorophyll breakdown during natural fruit ripening but is consistent with the notion that chlorophyll is gradually degraded during ripening due to a negative balance between synthesis and breakdown. According to this model, exogenous application of ethylene accelerates chlorophyll breakdown due to increased de novo synthesis of chlorophyllase. Further experimentation on the regulation and role of chlorophyllase in planta will be facilitated by the gene tools established in this work.


Assuntos
Hidrolases de Éster Carboxílico/genética , Hidrolases de Éster Carboxílico/metabolismo , Clorofila/metabolismo , Citrus/enzimologia , Citrus/genética , Genes de Plantas , Sequência de Aminoácidos , Sequência de Bases , Citrus/crescimento & desenvolvimento , Primers do DNA/genética , DNA Complementar/genética , DNA Complementar/isolamento & purificação , DNA de Plantas/genética , DNA de Plantas/isolamento & purificação , Escherichia coli/genética , Etilenos/farmacologia , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Giberelinas/farmacologia , Dados de Sequência Molecular , Reguladores de Crescimento de Plantas/farmacologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA de Plantas/genética , RNA de Plantas/metabolismo , Proteínas Recombinantes de Fusão/genética
10.
J Biol Chem ; 272(5): 2963-8, 1997 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-9006943

RESUMO

Human chymase and rat chymase-1 are mast cell serine proteases involved in angiotensin II (Ang II) formation and degradation, respectively. Previous studies indicate that both these enzymes have similar P1 and P2 preferences, which are the major determinants of specificity. Surprisingly, despite the occurrence of optimal P2 and P1 residues at the Phe8 downward arrow and Tyr4 downward arrow bonds (where downward arrow, indicates the scissile bond in peptide substrates) in Ang I (DRVYIHPFHL), human chymase cleaves the Phe8 downward arrow bond with an approximately 750-fold higher catalytic efficiency (kcat/Km) than the Tyr4 downward arrow bond in Ang II (DRVYIHPF), whereas rat chymase-1 cleaves the Tyr4 downward arrow bond with an approximately 20-fold higher catalytic efficiency than the Phe8 downward arrow bond. Differences in the acyl groups IHPF and DRVY at the Phe8 downward arrow and Tyr4 downward arrow bonds, respectively, are chiefly responsible for the preference of human chymase for the Phe8 downward arrow bond. We show that the IHPF sequence forms an optimal acyl group, primarily through synergistic interactions between neighboring acyl group residues. In contrast to human chymase, rat chymase-1 shows a preference for the Tyr4 downward arrow bond, mainly because of a catalytically productive interaction between the enzyme and the P'1 Ile5. The overall effect of this P'1 Ile interaction on catalytic efficiency, however, is influenced by the structure of the acyl group and that of the other leaving group residues. For human chymase, the P'1 Ile interaction is not productive. Thus, specificity for Ang II formation versus Ang II degradation by these chymases is produced through synergistic interactions between acyl or leaving group residues as well as between the acyl and leaving groups. These observations indicate that nonadditive interactions between the extended substrate binding site of human chymase or rat chymase-1 and the substrate are best explained if the entire binding site is taken as an entity rather than as a collection of distinct subsites.


Assuntos
Angiotensina II/metabolismo , Serina Endopeptidases/metabolismo , Sequência de Aminoácidos , Animais , Sítios de Ligação , Quimases , Ventrículos do Coração , Humanos , Cinética , Mastócitos/enzimologia , Miocárdio/enzimologia , Oligopeptídeos/química , Oligopeptídeos/metabolismo , Ratos , Análise de Regressão , Serina Endopeptidases/isolamento & purificação , Especificidade por Substrato , Termodinâmica
11.
Pediatrics ; 107(5): E77, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11331727

RESUMO

OBJECTIVE: To determine the effect of protease inhibitors (PIs) on growth and body composition in children with human immunodeficiency virus type 1 (HIV-1) infection. BACKGROUND: HIV-1-infected children have chronic problems with both linear growth and weight gain. Viral load may directly influence growth and nutritional status of HIV-1-infected children with reduction of viral load improving the nutritional condition. DESIGN/METHODS: Data from 67 patients who initiated PI therapy between 1996 and 1999 and who were enrolled in a prospective, longitudinal study of growth and nutrition in HIV-1-infected children were analyzed. Outcomes included pre-PI versus post-PI measures of height, weight, weight-for-height, triceps skinfold thickness, and arm muscle circumference. Predictor covariates included age, race, gender, Tanner stage, CD4 z score, Centers for Disease Control and Prevention stage, route of infection, plasma HIV-1 RNA, other antiretroviral therapy, recommended daily allowances for calories, treatment with megestrol acetate, and PI therapy. RESULTS: Sixty-seven children were followed for a median of 2.4 years with a total of 362 visits (median: 5 visits; range: 1-12). During follow-up, they received PIs for a median of 5 months. Fifty-one percent were girls, 54% black, 15% Hispanic, and 25% white. The mean age at first visit was 6.8 years. In a univariate analysis, weight z score (-0.67 to -0.35) and weight/height z score (0.25-0.76) improved on PI therapy. Using repeated-measures regression analysis, controlling for the above named covariates, PI treatment showed a significant effect on weight z score (increase in z score by 0.46), weight/height z score (increase in z score by 0.49), and arm muscle circumference (increase in percentile by 11.5). A borderline effect was found for height z score (increase in z score by 0.17) and no effect was found for triceps skinfold thickness. In a separate analysis, PI therapy increased CD4 counts twofold and reduced plasma HIV-1 RNA copies by 79%. CONCLUSION: In addition to a significant reduction in viral load, PI therapy in children has a positive effect on several growth parameters, including weight, weight/height, and muscle mass.


Assuntos
Composição Corporal/efeitos dos fármacos , Crescimento/efeitos dos fármacos , Infecções por HIV/tratamento farmacológico , Inibidores da Protease de HIV/farmacologia , Antropometria , Contagem de Linfócito CD4 , Criança , Ingestão de Energia , Feminino , Infecções por HIV/fisiopatologia , Inibidores da Protease de HIV/uso terapêutico , HIV-1 , Humanos , Estudos Longitudinais , Masculino , Análise Multivariada , Análise de Regressão , Carga Viral
13.
Korot ; 8(7-8): 305-17, 1983 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11630957
14.
Korot ; 8(3-4): 213-20, 1982 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11630818
17.
Korot ; 8(11-12): 4-23, 1985.
Artigo em Inglês | MEDLINE | ID: mdl-11614050
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