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1.
J Prev Alzheimers Dis ; 9(3): 523-531, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35841253

RESUMEN

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.


Asunto(s)
Enfermedad de Alzheimer , Envejecimiento/fisiología , Senescencia Celular/fisiología , Estudio de Asociación del Genoma Completo , Humanos
2.
Eur J Appl Physiol ; 122(2): 531-539, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34853894

RESUMEN

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.


Asunto(s)
Rendimiento Atlético/fisiología , Entrenamiento de Intervalos de Alta Intensidad , Resistencia Física/fisiología , Adolescente , Adulto , Prueba de Esfuerzo , Humanos , Masculino , Fuerza Muscular/fisiología
3.
Anaesthesist ; 64(5): 385-9, 2015 May.
Artículo en Alemán | MEDLINE | ID: mdl-25896415

RESUMEN

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.


Asunto(s)
Oxigenación por Membrana Extracorpórea/métodos , Embolia Pulmonar/terapia , Adulto , Disnea/terapia , Endarterectomía , Oxigenación por Membrana Extracorpórea/instrumentación , Femenino , Humanos , Hipotensión/terapia , Unidades Móviles de Salud , Transferencia de Pacientes , Cuidados Preoperatorios , Embolia Pulmonar/cirugía , Choque Cardiogénico/tratamiento farmacológico , Terapia Trombolítica
4.
Clin Ter ; 161(6): 537-41, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-21181084

RESUMEN

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.


Asunto(s)
Enfermedad Crónica/prevención & control , Actividad Motora , Enfermedad Crónica/tratamiento farmacológico , Enfermedad Crónica/terapia , Terapia Combinada , Ensayos Clínicos Controlados como Asunto , Terapia por Ejercicio , Promoción de la Salud , Humanos , Prevención Primaria , Calidad de Vida , Prevención Secundaria , Resultado del Tratamiento
5.
Acta Psychiatr Scand ; 113(4): 360-3; discussion 363-4, 2006 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16638081

RESUMEN

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.


Asunto(s)
Amígdala del Cerebelo/fisiopatología , Amígdala del Cerebelo/cirugía , Epilepsia/etiología , Epilepsia/fisiopatología , Epilepsia/cirugía , Hipocampo/fisiopatología , Hipocampo/cirugía , Procedimientos Neuroquirúrgicos/métodos , Complicaciones Posoperatorias , Trastornos por Estrés Postraumático/etiología , Trastornos por Estrés Postraumático/fisiopatología , Adulto , Niño , Abuso Sexual Infantil/psicología , Trastornos del Conocimiento/diagnóstico , Diagnóstico Diferencial , Femenino , Humanos , Incesto/psicología , Pruebas Neuropsicológicas , Cuidados Preoperatorios , Trastornos por Estrés Postraumático/terapia
6.
Brain Res Mol Brain Res ; 125(1-2): 13-21, 2004 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-15193418

RESUMEN

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.


Asunto(s)
Sistema Nervioso Central/enzimología , Oxidorreductasas/metabolismo , Animales , Línea Celular Tumoral , Cobayas , Humanos , Inmunohistoquímica , Hibridación in Situ , Neuronas/citología , Neuronas/enzimología , Oxidación-Reducción , Oxidorreductasas/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
7.
Clin Biochem ; 36(8): 621-8, 2003 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-14636877

RESUMEN

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.


Asunto(s)
Endometrio/química , Endometrio/enzimología , Tinción con Nitrato de Plata/métodos , Telomerasa/análisis , Telomerasa/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Animales , Endometrio/patología , Femenino , Cobayas , Células HeLa , Humanos , Persona de Mediana Edad
8.
Biochem Biophys Res Commun ; 287(1): 83-91, 2001 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-11549257

RESUMEN

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.


Asunto(s)
Estro/metabolismo , Oxidorreductasas/aislamiento & purificación , Útero/enzimología , Secuencia de Aminoácidos , Animales , Ciclo Celular/fisiología , ADN Complementario/análisis , Proteínas de Unión al ADN/química , Endometrio/metabolismo , Estrógenos/farmacología , Femenino , Regulación Enzimológica de la Expresión Génica , Biblioteca de Genes , Cobayas , Proteínas HMGB , Humanos , Datos de Secuencia Molecular , Proteínas Nucleares/química , Especificidad de Órganos , Oxidorreductasas/biosíntesis , Oxidorreductasas/genética , ARN Mensajero/efectos de los fármacos , ARN Mensajero/metabolismo , Ratas , Factores de Transcripción SOXB1 , Homología de Secuencia de Aminoácido , Factores de Transcripción , Útero/citología
9.
Biochem Biophys Res Commun ; 284(1): 118-25, 2001 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-11374880

RESUMEN

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.


Asunto(s)
Estrógenos , Regulación de la Expresión Génica/fisiología , Proteínas Asociadas a Microtúbulos/genética , Transcripción Genética , Regiones no Traducidas 3' , Proteínas Adaptadoras Transductoras de Señales , Animales , Proteínas Reguladoras de la Apoptosis , Secuencia de Bases , Clonación Molecular , ADN Complementario/genética , ADN Complementario/aislamiento & purificación , Estrógenos/farmacología , Exones , Femenino , Regulación de la Expresión Génica/efectos de los fármacos , Biblioteca Genómica , Cobayas , Humanos , Intrones , Proteínas Asociadas a Microtúbulos/biosíntesis , Datos de Secuencia Molecular , Especificidad de Órganos , Placenta , ARN Mensajero/biosíntesis , Análisis de Secuencia de ADN , Homología de Secuencia de Aminoácido , Homología de Secuencia de Ácido Nucleico , Transcripción Genética/efectos de los fármacos
10.
FEBS Lett ; 472(2-3): 241-6, 2000 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-10788619

RESUMEN

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.


Asunto(s)
Antineoplásicos/farmacología , Hormona Liberadora de Gonadotropina/farmacología , Inmunotoxinas/farmacología , N-Glicosil Hidrolasas , Proteínas de Plantas/farmacología , Ensayos de Selección de Medicamentos Antitumorales , Expresión Génica , Hormona Liberadora de Gonadotropina/genética , Humanos , Inmunotoxinas/genética , Inmunotoxinas/aislamiento & purificación , Proteínas de Plantas/genética , Receptores LHRH/metabolismo , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/aislamiento & purificación , Proteínas Recombinantes de Fusión/farmacología , Proteínas Inactivadoras de Ribosomas Tipo 1 , Células Tumorales Cultivadas
11.
FEBS Lett ; 410(2-3): 303-8, 1997 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-9237651

RESUMEN

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.


Asunto(s)
Antivirales/análisis , N-Glicosil Hidrolasas , Proteínas de Plantas/análisis , Animales , Antivirales/farmacología , Electroforesis en Gel de Poliacrilamida , Ensayo de Inmunoadsorción Enzimática , Ratones , Peso Molecular , Proteínas de Plantas/farmacología , Plantas/química , Desnaturalización Proteica , Proteínas Inactivadoras de Ribosomas Tipo 1
12.
J Mol Cell Cardiol ; 29(11): 3115-22, 1997 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9405185

RESUMEN

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.


Asunto(s)
Circulación Coronaria/fisiología , Endotelina-1/farmacología , Espectroscopía de Resonancia Magnética/métodos , Microscopía/métodos , Isquemia Miocárdica/fisiopatología , Oligopéptidos/farmacología , Animales , Color , Circulación Coronaria/efectos de los fármacos , Endotelina-1/antagonistas & inhibidores , Técnicas In Vitro , Masculino , Microcirculación/efectos de los fármacos , Microcirculación/fisiología , Microesferas , Daño por Reperfusión Miocárdica/fisiopatología , Perfusión , Ratas , Ratas Wistar , Sistema Vasomotor/efectos de los fármacos , Sistema Vasomotor/fisiología
13.
J Mol Cell Cardiol ; 28(3): 571-7, 1996 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9011640

RESUMEN

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.


Asunto(s)
Corazón/fisiología , Espectroscopía de Resonancia Magnética/métodos , Animales , Color , Técnicas In Vitro , Espectroscopía de Resonancia Magnética/instrumentación , Masculino , Microesferas , Poliestirenos , Ratas , Ratas Wistar
14.
Hybridoma ; 14(6): 571-5, 1995 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8770645

RESUMEN

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.


Asunto(s)
Anticuerpos Monoclonales/biosíntesis , Anticuerpos Monoclonales/química , N-Glicosil Hidrolasas , Proteínas de Plantas/inmunología , Inhibidores de la Síntesis de la Proteína/inmunología , Animales , Anticuerpos Monoclonales/aislamiento & purificación , Especificidad de Anticuerpos , Hibridomas/química , Hibridomas/metabolismo , Inmunización , Ratones , Ratones Endogámicos BALB C , Proteínas de Plantas/aislamiento & purificación , Inhibidores de la Síntesis de la Proteína/aislamiento & purificación , Proteínas Inactivadoras de Ribosomas Tipo 1
15.
Biochem J ; 292 ( Pt 3): 863-72, 1993 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-7686368

RESUMEN

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.


Asunto(s)
Anticuerpos Monoclonales , Epítopos/análisis , Hidroxibutirato Deshidrogenasa/química , Membranas Intracelulares/enzimología , Mitocondrias Cardíacas/enzimología , Mitocondrias Hepáticas/enzimología , Conformación Proteica , Animales , Western Blotting , Carboxipeptidasas/metabolismo , Bovinos , Hidroxibutirato Deshidrogenasa/inmunología , Hidroxibutirato Deshidrogenasa/metabolismo , Cinética , Liposomas , Peso Molecular , Mapeo Peptídico , Fosfolípidos/farmacología , Ratas
16.
Ann Radiol (Paris) ; 36(2): 129-33, 1993.
Artículo en Francés | MEDLINE | ID: mdl-8333713

RESUMEN

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.


Asunto(s)
Aneurisma/complicaciones , Síndrome de Ehlers-Danlos/complicaciones , Arteria Hepática/fisiopatología , Arteria Esplénica/fisiopatología , Trombosis/etiología , Adulto , Aneurisma/diagnóstico por imagen , Arterias/fisiopatología , Hemoperitoneo/etiología , Arteria Hepática/diagnóstico por imagen , Humanos , Masculino , Páncreas/irrigación sanguínea , Arteria Esplénica/diagnóstico por imagen , Trombosis/diagnóstico por imagen , Factores de Tiempo , Tomografía Computarizada por Rayos X
17.
Biochem Int ; 23(3): 429-37, 1991 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-1877981

RESUMEN

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.


Asunto(s)
Autoantígenos/inmunología , Enfermedades Autoinmunes/inmunología , Cirrosis Hepática Biliar/enzimología , Mitocondrias Hepáticas/enzimología , Complejo Piruvato Deshidrogenasa/inmunología , Humanos , Immunoblotting , Cirrosis Hepática Biliar/inmunología , Mitocondrias Hepáticas/inmunología
18.
J Chromatogr ; 539(2): 279-87, 1991 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-2045445

RESUMEN

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.


Asunto(s)
Cromatografía en Gel/métodos , Hidroxibutirato Deshidrogenasa/metabolismo , Membranas Intracelulares/enzimología , Mitocondrias Hepáticas/ultraestructura , Fosfolípidos/fisiología , Animales , Cromatografía en Gel/instrumentación , Activación Enzimática/fisiología , Vidrio , Hidroxibutirato Deshidrogenasa/aislamiento & purificación , Membranas Intracelulares/química , Microesferas , Mitocondrias Hepáticas/química , Mitocondrias Hepáticas/enzimología , Fosfolípidos/metabolismo , Ratas
19.
J Chromatogr ; 521(2): 169-78, 1990 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-2286634

RESUMEN

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.


Asunto(s)
Cromatografía Líquida de Alta Presión , Complejo Piruvato Deshidrogenasa/aislamiento & purificación , Animales , Bovinos , Electroforesis en Gel de Poliacrilamida , Estabilidad de Enzimas , Peso Molecular , Miocardio/enzimología , Complejo Piruvato Deshidrogenasa/química , Thermus/enzimología
20.
C R Seances Soc Biol Fil ; 181(4): 383-8, 1987.
Artículo en Francés | MEDLINE | ID: mdl-2963675

RESUMEN

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.


Asunto(s)
Diabetes Mellitus Experimental/metabolismo , Hidroxibutirato Deshidrogenasa/genética , Animales , Diabetes Mellitus Experimental/enzimología , Regulación de la Expresión Génica , Hidroxibutirato Deshidrogenasa/metabolismo , Insulina/fisiología , Masculino , Mitocondrias/metabolismo , Polirribosomas/metabolismo , Biosíntesis de Proteínas , Ratas , Estreptozocina , Transcripción Genética
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