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1.
J Prev Alzheimers Dis ; 9(3): 523-531, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35841253

RESUMO

The underlying processes occurring in aging are complex, involving numerous biological changes that result in chronic cellular stress and sterile inflammation. One of the main hallmarks of aging is senescence. While originally the term senescence was defined in the field of oncology, further research has established that also microglia, astrocytes and neurons become senescent. Since age is the main risk factor for neurodegenerative diseases, it is reasonable to argue that cellular senescence might play a major role in Alzheimer's disease. Specific cellular changes seen during Alzheimer's disease are similar to those observed during senescence across all resident brain cell types. Furthermore, increased levels of senescence-associated secretory phenotype proteins such as IL-6, IGFBP, TGF-ß and MMP-10 have been found in both CSF and plasma samples from Alzheimer's disease patients. In addition, genome-wide association studies have identified that individuals with Alzheimer's disease carry a high burden of genetic risk variants in genes known to be involved in senescence, including ADAM10, ADAMTS4, and BIN1. Thus, cellular senescence is emerging as a potential underlying disease process operating in Alzheimer's disease. This has also attracted more attention to exploiting cellular senescence as a therapeutic target. Several senolytic compounds with the capability to eliminate senescent cells have been examined in vivo and in vitro with notable results, suggesting they may provide a novel therapeutic avenue. Here, we reviewed the current knowledge of cellular senescence and discussed the evidence of senescence in various brain cell types and its putative role in inflammaging and neurodegenerative processes.


Assuntos
Doença de Alzheimer , Envelhecimento/fisiologia , Senescência Celular/fisiologia , Estudo de Associação Genômica Ampla , Humanos
2.
Eur J Appl Physiol ; 122(2): 531-539, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34853894

RESUMO

INTRODUCTION: High intensity functional trainings (HIFT), a recent development of high intensity trainings, includes in the same training session components of endurance exercises, elements of Olympic weightlifting and powerlifting, gymnastics, plyometrics and calisthenics exercises. Therefore, subjects practicing this type of activity are supposed to show physiological features that represent a combination of both endurance and power athletes. The aim of this study was to compare the physiological profile of three groups of age-matched endurance, HIFT and power athletes. METHODS: A total of 30 participants, 18 to 38-year-old men were enrolled in the study. Participants were divided in three groups: HIFT (n = 10), endurance (END, n = 10), and power (POW, weightlifters, n = 10) athletes. All were evaluated for anthropometric characteristics, VO2peak, handgrip, lower limb maximal isometric and isokinetic strength, countermovement vertical jump and anaerobic power through a shuttle run test on the field. RESULTS: VO2peak/kg was higher in END and HIFT than POW athletes (p = 0.001 and p = 0.007, respectively), but there were no significant differences between the first two. POW and HIFT athletes showed significant greater strength at the handgrip, countermovement jump and leg extension/flexion tests than END athletes. HIFT athletes showed highest results at the dynamic isokinetic test, while there were no significant differences at the shuttle run test among groups. CONCLUSIONS: As HIFT reach aerobic levels similar to END athletes and power and strength output similar to POW athletes, it appears that HIFT programs are effective to improve both endurance-related and power-related physical fitness components.


Assuntos
Desempenho Atlético/fisiologia , Treinamento Intervalado de Alta Intensidade , Resistência Física/fisiologia , Adolescente , Adulto , Teste de Esforço , Humanos , Masculino , Força Muscular/fisiologia
3.
Anaesthesist ; 64(5): 385-9, 2015 May.
Artigo em Alemão | MEDLINE | ID: mdl-25896415

RESUMO

The current report highlights the use of venoarterial extracorporeal membrane oxygenation (va-ECMO) in a case of pulmonary embolism complicated by right ventricular failure. A 38-year-old woman was admitted to a secondary care hospital with dyspnea and systemic hypotension. Diagnostic testing revealed a massive pulmonary embolism. Thrombolytic therapy was unsuccessful necessitating thromboendarterectomy in the presence of cardiogenic shock. To allow the necessary transport of the highly unstable patient to a tertiary care center a mobile ECMO team was called in. The team immediately initiated awake va-ECMO as a bridge to therapy. Extracorporeal support subsequently allowed a safe transportation and successful completion of the surgical procedure with complete recovery.


Assuntos
Oxigenação por Membrana Extracorpórea/métodos , Embolia Pulmonar/terapia , Adulto , Dispneia/terapia , Endarterectomia , Oxigenação por Membrana Extracorpórea/instrumentação , Feminino , Humanos , Hipotensão/terapia , Unidades Móveis de Saúde , Transferência de Pacientes , Cuidados Pré-Operatórios , Embolia Pulmonar/cirurgia , Choque Cardiogênico/tratamento farmacológico , Terapia Trombolítica
4.
Clin Ter ; 161(6): 537-41, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21181084

RESUMO

The aim of this review is to assess the current evidence in scientific literature that supports the use of physical activity as a fundamental tool for primary and secondary prevention and to encourage its use conscientiously. Observational studies and international guidelines have been examined to evaluate the positive effects of physical activity as primary prevention on some of the most common diseases. We have also evaluated those studies which demonstrate that the association of physical activity with drug therapy in chronic diseases results in a better prognosis. We researched the Cochrane Controlled Trials Register, MEDLINE, PubMed up to January 2009. Furthermore, we screened references in relevant reviews and clinical trials. Sixty four studies were included in the review and cited as giving consistent evidence for the utilization of physical activity to improve health. There is strong evidence that, according to international guidelines, physical activity should be adopted as a tool in the prevention and treatment of many chronic diseases.


Assuntos
Doença Crônica/prevenção & controle , Atividade Motora , Doença Crônica/tratamento farmacológico , Doença Crônica/terapia , Terapia Combinada , Ensaios Clínicos Controlados como Assunto , Terapia por Exercício , Promoção da Saúde , Humanos , Prevenção Primária , Qualidade de Vida , Prevenção Secundária , Resultado do Tratamento
5.
Acta Psychiatr Scand ; 113(4): 360-3; discussion 363-4, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16638081

RESUMO

OBJECTIVE: The case report suggests the indispensability of preoperative accurate psychiatric checkups especially in temporal resections. METHOD: A single case was reported. RESULTS: We report the case of a 20-year-old woman suffering for 12 years from primary generalized epilepsy, attributed to left-sided hippocampal sclerosis. Because seizures were resistant to drug therapy, she underwent amygdala-hippocampectomy at the age of 18. Furthermore, she had previously been victim of childhood sexual abuse. Two weeks after epilepsy surgery, she manifested symptoms of post-traumatic stress disorder (PTSD). CONCLUSION: There is evidence that the amygdala-hippocampal region is both functionally and morphologically involved in the aetiology of PTSD. The removal of this marked neuroanatomical region and the resulting disconnection and asymmetry between right and left amygdala-hippocampal region might be seen as an evidence for this region aetiologically being involved in the patient's PTSD symptoms.


Assuntos
Tonsila do Cerebelo/fisiopatologia , Tonsila do Cerebelo/cirurgia , Epilepsia/etiologia , Epilepsia/fisiopatologia , Epilepsia/cirurgia , Hipocampo/fisiopatologia , Hipocampo/cirurgia , Procedimentos Neurocirúrgicos/métodos , Complicações Pós-Operatórias , Transtornos de Estresse Pós-Traumáticos/etiologia , Transtornos de Estresse Pós-Traumáticos/fisiopatologia , Adulto , Criança , Abuso Sexual na Infância/psicologia , Transtornos Cognitivos/diagnóstico , Diagnóstico Diferencial , Feminino , Humanos , Incesto/psicologia , Testes Neuropsicológicos , Cuidados Pré-Operatórios , Transtornos de Estresse Pós-Traumáticos/terapia
6.
Brain Res Mol Brain Res ; 125(1-2): 13-21, 2004 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-15193418

RESUMO

cpQSOx1 is a member of the QSOx family of proteins, expressed in the guinea pig (Cavia porcellus) and ortholog of the rat rQSOx1. In this study, in vitro experiments were conducted and showed that, as other member of this family, cpQSOx1 has a sulfydryl oxidase activity, and is a secreted protein. Then, the expression of this enzyme was researched in the guinea pig brain, as very little information exists yet on the expression of QSOx family members in the central nervous system. By immunohistochemistry, RT-PCR and in situ hybridization, cpQSOx1 is synthesized by neurons throughout the whole guinea pig central nervous system. Reticular structures as the basal forebrain, reticular thalamic nucleus and reticular nuclei of the brainstem contained the densest labeling. These results are discussed in terms of putative roles of this protein in synaptic strengthening and in redox activities.


Assuntos
Sistema Nervoso Central/enzimologia , Oxirredutases/metabolismo , Animais , Linhagem Celular Tumoral , Cobaias , Humanos , Imuno-Histoquímica , Hibridização In Situ , Neurônios/citologia , Neurônios/enzimologia , Oxirredução , Oxirredutases/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
7.
Clin Biochem ; 36(8): 621-8, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14636877

RESUMO

OBJECTIVES: To develop a sensitive telomeric repeat amplification protocol (TRAP)-silver staining assay for telomerase activity quantification. DESIGN AND METHODS: TRAP assays were performed by using a TRAPeze telomerase kit with or without [alpha-32P]-dCTP. Amplification products were electrophoresed in polyacrylamide gels and detected by autoradiography or a modified silver staining protocol. Telomerase activity was quantified from radioactive counts or optical density of telomerase products from test extracts and controls. RESULTS: TRAP-silver staining assay was at least as sensitive as radioactive TRAP assay and quantified telomerase activity within linearity from 10 to 3,000 cell equivalents. Both methods quantified a weak telomerase activity in normal endometrial glandular epithelial cells (GEC) and a strong increase in immortalized GEC. In human pathologic endometria (n=24), telomerase activity was correlated with lesion seriousness and distinguished simple hyperplasias from nonhyperplasic or cancerous lesions. CONCLUSIONS: TRAP-silver staining assay is suitable for cell and tissue telomerase activity routine quantification.


Assuntos
Endométrio/química , Endométrio/enzimologia , Coloração pela Prata/métodos , Telomerase/análise , Telomerase/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Endométrio/patologia , Feminino , Cobaias , Células HeLa , Humanos , Pessoa de Meia-Idade
8.
Biochem Biophys Res Commun ; 287(1): 83-91, 2001 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-11549257

RESUMO

Using differential hybridization of a guinea pig endometrial cell cDNA library, a potentially negatively estrogen-regulated gene, SOX-3, was isolated. According to the nucleotide and protein sequence similarities, SOx-3 belonged to the FAD-linked sulfhydryl oxidase family containing the egg white sulfhydryl oxidase, the rat seminal vesicle sulfhydryl oxidase-2 SOx-2, the quiescence-inducible protein hQ6. The SOX-3 transcript in the guinea pig as well as 5 different mRNAs in human tissues appeared differentially expressed in the tissues studied. In secondary endometrial cell culture, the SOX-3 mRNA level increased during a serum depletion-induced quiescence, decreased when cells enter the G1 phase after serum stimulation, and was restored during the S and G2/M phases. Thus, SOX-3 could be implicated in the negative cell cycle control. The SOx-3 protein appeared to be specific of epithelial cells in the uterus. Its expression level varied during the estrus cycle in the guinea pig, suggesting a regulation by steroid hormones.


Assuntos
Estro/metabolismo , Oxirredutases/isolamento & purificação , Útero/enzimologia , Sequência de Aminoácidos , Animais , Ciclo Celular/fisiologia , DNA Complementar/análise , Proteínas de Ligação a DNA/química , Endométrio/metabolismo , Estrogênios/farmacologia , Feminino , Regulação Enzimológica da Expressão Gênica , Biblioteca Gênica , Cobaias , Proteínas HMGB , Humanos , Dados de Sequência Molecular , Proteínas Nucleares/química , Especificidade de Órgãos , Oxirredutases/biossíntese , Oxirredutases/genética , RNA Mensageiro/efeitos dos fármacos , RNA Mensageiro/metabolismo , Ratos , Fatores de Transcrição SOXB1 , Homologia de Sequência de Aminoácidos , Fatores de Transcrição , Útero/citologia
9.
Biochem Biophys Res Commun ; 284(1): 118-25, 2001 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-11374880

RESUMO

We have isolated, in guinea-pig endometrial cells, an estrogen-induced 1.8 kb RNA called gec1. Screening of a guinea-pig genomic library led to identification of gec1 gene consisting of 4 exons and 3 introns. Exon 1 contains the 5'UTR and the ATG initiation codon. A guinea-pig gec1 cDNA was obtained by 5'-RACE. The 351 bp coding sequence shares 76.8% identity with that of the human GABARAP 924 bp cDNA while UTRs of the two cDNAs differ. A gec1 probe from the 3'UTR revealed a 1.9 kb mRNA in human tissues and a human GEC1 cDNA was isolated from placenta. Its coding sequence shares 93 and 79% identity with that of guinea-pig gec1 and human GABARAP, respectively. The human and guinea-pig GEC1 proteins have 100% identity. GEC1 and GABARAP proteins have 87% identity and N terminus featuring a tubulin binding motif. Thus, estrogen-regulated gec1 is a new gene which could encode a microtubule-associated protein.


Assuntos
Estrogênios , Regulação da Expressão Gênica/fisiologia , Proteínas Associadas aos Microtúbulos/genética , Transcrição Gênica , Regiões 3' não Traduzidas , Proteínas Adaptadoras de Transdução de Sinal , Animais , Proteínas Reguladoras de Apoptose , Sequência de Bases , Clonagem Molecular , DNA Complementar/genética , DNA Complementar/isolamento & purificação , Estrogênios/farmacologia , Éxons , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Biblioteca Genômica , Cobaias , Humanos , Íntrons , Proteínas Associadas aos Microtúbulos/biossíntese , Dados de Sequência Molecular , Especificidade de Órgãos , Placenta , RNA Mensageiro/biossíntese , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Homologia de Sequência do Ácido Nucleico , Transcrição Gênica/efeitos dos fármacos
10.
FEBS Lett ; 472(2-3): 241-6, 2000 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-10788619

RESUMO

Pokeweed antiviral protein (PAP), a ribosome-inactivating protein isolated from the leaves of Phytolacca americana, reveals potent antiviral activity against viruses or cytotoxic action against cells once inside the cytoplasm. Therefore PAP is a good candidate to be used as an immunotoxin. We constructed a bacterial expression plasmid encoding PAP as a fusion protein with gonadotropin-releasing hormone (GnRH), a neuropeptide with receptor sites on several gynaecologic tumors. The resulting recombinant toxin was produced in Escherichia coli and accumulated in inclusion bodies. After purification under denaturing conditions, renaturated GnRH-PAP shows an IC(50) of 3 nM on in vitro translation assays and selectively inhibits the growth of the GnRH receptor positive Ishikawa cell line (ID(50) of 15 nM); on the other hand, neither GnRH nor PAP alone had any effect.


Assuntos
Antineoplásicos/farmacologia , Hormônio Liberador de Gonadotropina/farmacologia , Imunotoxinas/farmacologia , N-Glicosil Hidrolases , Proteínas de Plantas/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Expressão Gênica , Hormônio Liberador de Gonadotropina/genética , Humanos , Imunotoxinas/genética , Imunotoxinas/isolamento & purificação , Proteínas de Plantas/genética , Receptores LHRH/metabolismo , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/isolamento & purificação , Proteínas Recombinantes de Fusão/farmacologia , Proteínas Inativadoras de Ribossomos Tipo 1 , Células Tumorais Cultivadas
11.
FEBS Lett ; 410(2-3): 303-8, 1997 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-9237651

RESUMO

Pokeweed antiviral protein (PAP) inactivates both eukaryotic and prokaryotic ribosomes via a specific depurination of rRNA. The sensitivity of pokeweed ribosomes to PAP implies the existence of a mechanism to protect the plant. Using monoclonal antibodies specific to PAP, a protein complex (PAPi) which contained PAP was identified in leaf extract. In this complex, the enzymatic activity of the toxin was strongly inhibited. This protein complex had a pI lower than that of PAP and was separated from free PAP by a preparative native gel electrophoresis. PAPi had an apparent molecular mass of 57 kDa and was dissociated by heating for 5 min at 80 degrees C or by treatment by alkaline or acidic pH or by 7 M urea. The other components involved in the complex remain unknown.


Assuntos
Antivirais/análise , N-Glicosil Hidrolases , Proteínas de Plantas/análise , Animais , Antivirais/farmacologia , Eletroforese em Gel de Poliacrilamida , Ensaio de Imunoadsorção Enzimática , Camundongos , Peso Molecular , Proteínas de Plantas/farmacologia , Plantas/química , Desnaturação Proteica , Proteínas Inativadoras de Ribossomos Tipo 1
12.
J Mol Cell Cardiol ; 29(11): 3115-22, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9405185

RESUMO

Although the investigation of coronary microcirculation is of great importance, available methods have severe restrictions. They do not allow the study of vasodynamics of resistance vessels and microscopic conductance vessels simultaneously in the isolated beating rat heart. We now demonstrate that the combined measurement of perfusion which reflects the state of resistance vessels and cross-sections of microscopic conductance vessels is feasible in the model of the isolated constant flow perfused rat heart. Perfusion measurement was based on injection of coloured microspheres. Cross-sections of microscopic conductance vessels (diameter >140 micron) were determined by NMR-microscopy by flow weighted imaging. Both methods were established recently by our group. The combined measurement was applied to hearts which were subjected to ischaemia and reperfusion (group 1: n=5, 15 min ischaemia/group 2: n=7, 30 min ischaemia/measurements before ischaemia and 15/30 min after reperfusion), 200 pmol endothelin-1 bolus application (group 3: n=6/measurements before and 5 min after drug application), continuous infusion of the endothelin-1 antagonist BQ 610 (group 4: n=6/measurements before and 20 min after onset of infusion), and 200 pmol endothelin-1 application superimposed on 20 min of continuous BQ 610 infusion (group 5: n=7/combined measurement before BQ 610 infusion and 5 min after endothelin-1 application). In group 1, 15 min reperfusion restored the pre-ischaemic perfusion state, whereas conductance vessels were dilated (80.8+/-2.6%), after 30 min reperfusion pre-ischaemic conditions were also restored for conductance vessels. In group 2, a redistribution of perfusion from left ventricular endocardium to the right ventricular wall was observed. Post-ischaemic rhythm disturbances made NMR-imaging in this group impossible. In group 3, a shift of perfusion from the left ventricular myocardium to the right ventricular wall was observed. Similarly, the cross-section of left ventricular conductance vessels decreased (-32.6+/-2.1%), whereas size of right ventricular vessels increased. In group 4, BQ 610 had no effect on perfusion nor on vessel size and antagonized the effect of endothelin-1 on perfusion and vessel size in group 5.


Assuntos
Circulação Coronária/fisiologia , Endotelina-1/farmacologia , Espectroscopia de Ressonância Magnética/métodos , Microscopia/métodos , Isquemia Miocárdica/fisiopatologia , Oligopeptídeos/farmacologia , Animais , Cor , Circulação Coronária/efeitos dos fármacos , Endotelina-1/antagonistas & inibidores , Técnicas In Vitro , Masculino , Microcirculação/efeitos dos fármacos , Microcirculação/fisiologia , Microesferas , Traumatismo por Reperfusão Miocárdica/fisiopatologia , Perfusão , Ratos , Ratos Wistar , Sistema Vasomotor/efeitos dos fármacos , Sistema Vasomotor/fisiologia
13.
J Mol Cell Cardiol ; 28(3): 571-7, 1996 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9011640

RESUMO

Myocardial perfusion measurement with colored microspheres may become an alternative for radioactive microsphere techniques. We use and validate a spectrophotometric method that has been previously established for large animals in the isolated perfused rat heart. The perfusion system was adapted for use in a NMR microscope. Hearts were perfused with constant coronary flow that was adjusted to a coronary perfusion pressure of 100 mmHg. Homogeneous coronary inflow of microspheres was represented by equal distribution of microspheres of two different colors after simultaneous injection. Mean regional myocardial blood flow was 17.76 +/- 5.01 ml/min/g, mean wet heart weight was 1.13 +/- 0.34 g and mean global flow was 20.06 +/- 0.60 ml/min. Heart rate was 296 +/- 8.9 beats/min and left ventricular pressure was similar 5 min before (149.1 +/- 14.27 mmHg) and after (147.1 +/- 13.49 mmHg) microsphere injection. Microspheres of four colors that were injected sequentially, at various coronary flows, demonstrated linearity and reproducibility of the technique. A cumulative use of less than 90 000 microspheres showed no effect on hemodynamics especially on left ventricular pressure.


Assuntos
Coração/fisiologia , Espectroscopia de Ressonância Magnética/métodos , Animais , Cor , Técnicas In Vitro , Espectroscopia de Ressonância Magnética/instrumentação , Masculino , Microesferas , Poliestirenos , Ratos , Ratos Wistar
14.
Hybridoma ; 14(6): 571-5, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8770645

RESUMO

Monoclonal antibodies specific to pokeweed antiviral protein (PAP), a ribosome-inactivating protein (RIP), were obtained after six unsuccessful fusions. A special procedure including injections of low doses of purified PAP from spring leaves in a short period was adopted. Some clones highly specific to PAP react with recombinant PAP. One clone cross-reacts with PAP-S isolated from seeds but none cross-reacts with the isoform PAP II isolated from summer leaves. These antibodies represent a useful tool to investigate the mechanisms of PAP biosynthesis and plant protection involving RIPs.


Assuntos
Anticorpos Monoclonais/biossíntese , Anticorpos Monoclonais/química , N-Glicosil Hidrolases , Proteínas de Plantas/imunologia , Inibidores da Síntese de Proteínas/imunologia , Animais , Anticorpos Monoclonais/isolamento & purificação , Especificidade de Anticorpos , Hibridomas/química , Hibridomas/metabolismo , Imunização , Camundongos , Camundongos Endogâmicos BALB C , Proteínas de Plantas/isolamento & purificação , Inibidores da Síntese de Proteínas/isolamento & purificação , Proteínas Inativadoras de Ribossomos Tipo 1
15.
Biochem J ; 292 ( Pt 3): 863-72, 1993 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-7686368

RESUMO

Monoclonal antibodies (mAbs) have been used to study structure-function relationships of (R)-3-hydroxybutyrate dehydrogenase (BDH) (EC 1.1.1.30), a lipid-requiring mitochondrial membrane enzyme with an absolute and specific requirement for phosphatidylcholine (PC) for enzymic activity. The purified enzyme (apoBDH, devoid of phospholipid and thereby inactive) can be re-activated with preformed phospholipid vesicles containing PC or by short-chain soluble PC. Five of six mAbs cross-react with BDH from bovine heart and rat liver, including two mAbs to conformational epitopes. One mAb was found to be specific for the C-terminal sequence of BDH and served to: (1) map endopeptidase cleavage and epitope sites on BDH; and (2) demonstrate that the C-terminus is essential for the activity of BDH. Carboxypeptidase cleavage of only a few (< or = 14) C-terminal amino acids from apoBDH (as detected by the loss of C-terminal epitope for mAb 3-10A) prevents activation by either bilayer or soluble PC. Further, for BDH in bilayers containing PC, the C-terminus is protected from carboxy-peptidase cleavage, whereas in bilayers devoid of PC the C-terminus is cleaved, and subsequent activation by PC is precluded. We conclude that: (1) the C-terminus of BDH is essential for enzymic activity, consistent with the prediction, from primary sequence analysis, that the PC-binding site is in the C-terminal domain of BDH; and (2) the allosteric activation of BDH by PC in bilayers protects the C-terminus from carboxypeptidase cleavage, indicative of a PC-induced conformational change in the enzyme.


Assuntos
Anticorpos Monoclonais , Epitopos/análise , Hidroxibutirato Desidrogenase/química , Membranas Intracelulares/enzimologia , Mitocôndrias Cardíacas/enzimologia , Mitocôndrias Hepáticas/enzimologia , Conformação Proteica , Animais , Western Blotting , Carboxipeptidases/metabolismo , Bovinos , Hidroxibutirato Desidrogenase/imunologia , Hidroxibutirato Desidrogenase/metabolismo , Cinética , Lipossomos , Peso Molecular , Mapeamento de Peptídeos , Fosfolipídeos/farmacologia , Ratos
16.
Ann Radiol (Paris) ; 36(2): 129-33, 1993.
Artigo em Francês | MEDLINE | ID: mdl-8333713

RESUMO

Ehlers-Danlos syndrome is one of the most frequent hereditary connective tissue diseases. Type 4 or Sack-Barabas syndrome differs by the seventy of arterial complications. The authors report a case of severely progressive aneurysms since thrombosis of the aneurysm of the left hepatic artery, splenic artery, and small aneurysms of the lower pancreatic artery and rapid development of severe ectasia of the coeliac trunk and the commun hepatic artery all occurred over a period of three months.


Assuntos
Aneurisma/complicações , Síndrome de Ehlers-Danlos/complicações , Artéria Hepática/fisiopatologia , Artéria Esplênica/fisiopatologia , Trombose/etiologia , Adulto , Aneurisma/diagnóstico por imagem , Artérias/fisiopatologia , Hemoperitônio/etiologia , Artéria Hepática/diagnóstico por imagem , Humanos , Masculino , Pâncreas/irrigação sanguínea , Artéria Esplênica/diagnóstico por imagem , Trombose/diagnóstico por imagem , Fatores de Tempo , Tomografia Computadorizada por Raios X
17.
Biochem Int ; 23(3): 429-37, 1991 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-1877981

RESUMO

Primary biliary cirrhosis is an evolutive and chronic human liver disease characterized by presence of antimitochondrial autoantibodies in the serum. We present the biochemical definition of these autoantigens and show that purified pyruvate dehydrogenase complex contains three of the major mitochondrial antigens of M2 type i.e. the E2 subunit (dihydrolipoamide acetyl transferase), the X subunit and the E1 alpha subunit (pyruvate dehydrogenase), by immunoblotting experiments and inhibition of enzyme activity with several types of serums.


Assuntos
Autoantígenos/imunologia , Doenças Autoimunes/imunologia , Cirrose Hepática Biliar/enzimologia , Mitocôndrias Hepáticas/enzimologia , Complexo Piruvato Desidrogenase/imunologia , Humanos , Immunoblotting , Cirrose Hepática Biliar/imunologia , Mitocôndrias Hepáticas/imunologia
18.
J Chromatogr ; 539(2): 279-87, 1991 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-2045445

RESUMO

D-3-Hydroxybutyrate dehydrogenase (BDH) is an NAD(+)-dependent dehydrogenase of the mitochondrial inner membrane involved in the energetic balance between the liver and peripheral organs in mammals. It allows the conversion of ketone bodies (acetoacetate and D-3-hydroxybutyrate) and it is one of the best documented lipid-requiring enzymes with a dependence on lecithins. After release of proteins from the membrane by phospholipase A2 treatment of salt-treated mitochondria, the rat liver enzyme is absorbed on controlled-pore glass beads. After batch washing, the enzyme, devoid of lipids (apoBDH), is specifically eluted at pH 8.05-8.15 with a 0.1 M Tris-1 M LiBr buffer under reducing conditions (5 mM dithiothreitol). It appears that during BDH absorption, the glass beads mimic the phospholipid surface of biomembranes.


Assuntos
Cromatografia em Gel/métodos , Hidroxibutirato Desidrogenase/metabolismo , Membranas Intracelulares/enzimologia , Mitocôndrias Hepáticas/ultraestrutura , Fosfolipídeos/fisiologia , Animais , Cromatografia em Gel/instrumentação , Ativação Enzimática/fisiologia , Vidro , Hidroxibutirato Desidrogenase/isolamento & purificação , Membranas Intracelulares/química , Microesferas , Mitocôndrias Hepáticas/química , Mitocôndrias Hepáticas/enzimologia , Fosfolipídeos/metabolismo , Ratos
19.
J Chromatogr ; 521(2): 169-78, 1990 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-2286634

RESUMO

The pyruvate dehydrogenase complex is associated with the inner mitochondrial membrane. A gentle and rapid purification procedure, especially for the very unstable pyruvate dehydrogenase complex from the extremely thermophilic organism Thermus aquaticus, is described. This procedure is based essentially on a combination of hydrophobic interaction and of adsorption chromatography by the rapid fast protein liquid chromatographic technique. Applying the same method, a relative molecular mass of 9.1 . 10(6) daltons was obtained by gel filtration on Superose 6 HR 10/30 for the pyruvate dehydrogenase complex from T. aquaticus. The same column served to resolve the pyruvate dehydrogenase complex into its enzyme components.


Assuntos
Cromatografia Líquida de Alta Pressão , Complexo Piruvato Desidrogenase/isolamento & purificação , Animais , Bovinos , Eletroforese em Gel de Poliacrilamida , Estabilidade Enzimática , Peso Molecular , Miocárdio/enzimologia , Complexo Piruvato Desidrogenase/química , Thermus/enzimologia
20.
C R Seances Soc Biol Fil ; 181(4): 383-8, 1987.
Artigo em Francês | MEDLINE | ID: mdl-2963675

RESUMO

The effect of various metabolic conditions inducing an overproduction of ketone bodies in the rat have been studied at the different level of the D-beta-hydroxybutyrate dehydrogenase (BDH) expression: the enzymatic activity and the protein content in isolated mitochondria, and at the translational activity of isolated polysomes. The strongest variations were obtained under a diabete where the BDH expression is largely decreased. Insulin is able to reverse this diabete dramatic effect. The results are in agreement with the absence of direct relationships between the ketone bodies production and the D-beta-hydroxybutyrate dehydrogenase expression but appears to be controlled by insulin at different levels at least at the transcriptional, post translational and catalytic activities.


Assuntos
Diabetes Mellitus Experimental/metabolismo , Hidroxibutirato Desidrogenase/genética , Animais , Diabetes Mellitus Experimental/enzimologia , Regulação da Expressão Gênica , Hidroxibutirato Desidrogenase/metabolismo , Insulina/fisiologia , Masculino , Mitocôndrias/metabolismo , Polirribossomos/metabolismo , Biossíntese de Proteínas , Ratos , Estreptozocina , Transcrição Gênica
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