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1.
J Med Microbiol ; 73(4)2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38591530

RESUMEN

Sexually transmitted infections (STI) are a public health problem. Real-time PCR assays are the most sensitive test for screening and diagnosis of these infections. The aim of this study was to evaluate a new CT/NG/TV/MG Real-Time PCR (RT-PCR) kit (Vircell) for the detection of Chamydia trachomatis, Neisseria gonorrhoeae, Mycoplasma genitalium and Trichomonas vaginalis for the diagnosis of sexual transmitted infections using the Allplex STI Essential Assay (Seegene) as the reference's method. A total of 497 samples from different anatomical sites (endocervical, urethral, rectal, pharyngeal and urine) were analysed from October 2022 to February 2023. A total of 108 (21.73 %) and 106 (21.33 %) positive samples were found for any of the assays used. The most commonly detected pathogen was N. gonorrhoeae (52 samples; 10.46 %), and the least commonly detected was T. vaginalis (three samples; 0.60 %). The anatomical site with the highest prevalence of micro-organisms was a non-urogenital site, the pharynx (26 positive samples; 5.23 %). Using the Allplex STI Essential Assay (Seegene) as the reference method, the diagnosis performance showed that the average specificity of CT/NG/TV/MG RT-PCR Kit (Vircell) was 99.84 % and the sensitivity was 99.53 %. The overall concordance was k=0.98 (CI95 %; 0.96-1). In conclusion, the CT/NG/TV/MG RT-PCR Kit (Vircell) assay shows a good sensitivity and specificity and constitutes a promising and additional alternative to routine procedures for distinct types of clinical specimen in diagnosis STI.


Asunto(s)
Infecciones por Chlamydia , Gonorrea , Infecciones por Mycoplasma , Mycoplasma genitalium , Enfermedades de Transmisión Sexual , Trichomonas vaginalis , Humanos , Reacción en Cadena en Tiempo Real de la Polimerasa , Chlamydia trachomatis/genética , Enfermedades de Transmisión Sexual/diagnóstico , Enfermedades de Transmisión Sexual/epidemiología , Trichomonas vaginalis/genética , Neisseria gonorrhoeae/genética , Mycoplasma genitalium/genética , Infecciones por Mycoplasma/diagnóstico , Infecciones por Mycoplasma/epidemiología , Tomografía Computarizada por Rayos X , Infecciones por Chlamydia/diagnóstico , Gonorrea/diagnóstico , Gonorrea/epidemiología
2.
Rev Clin Esp (Barc) ; 217(8): 454-459, 2017 Nov.
Artículo en Inglés, Español | MEDLINE | ID: mdl-28830616

RESUMEN

OBJECTIVES: In recent years, various scientific societies and healthcare organisations have created recommendations aimed at decreasing the use of healthcare interventions that have shown no efficacy or effectiveness. The aim of this study was to assess the impact of an intervention on 12 do-not-do recommendations regarding the laboratory in 7 hospital centres. METHODS: Before-after study conducted in 7 hospital centres of Cordoba and Jaen during 2015 and 2016. Based on the recommendations of existing scientific societies, a consensus was reached on various actions regarding laboratory measurements. We analysed the number and cost of measuring 6 tumour markers (carcinoembryonic antigen, prostate-specific antigen, carbohydrate antigen [CA] 15.3, CA125, CA19.9 and alpha-fetoprotein), thyrotropin, T3, T4, glycated haemoglobin, urea, ferritin and antigliadin antibodies, before and after implementing the consensus. RESULTS: Compared with the previous year, there were 55,902 fewer laboratory measurements (-19%) in 2016, with an overall savings of €82,100. The reduction in the number of measurements occurred mainly in plasma urea (-50.3%) and in the tumour markers CA125 (-16%), CA19.9 (-11.6%) and CA15.3 (-10.5%). The most pronounced savings were achieved in the measurements of urea (-€21,002), thyroid hormones (-€12,716) and thyrotropin (-€7,638). CONCLUSIONS: The adoption and consensus of do-not-do recommendations among healthcare levels resulted in a significant reduction in unnecessary measurements.

3.
Colloids Surf B Biointerfaces ; 152: 199-213, 2017 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-28110042

RESUMEN

Compartmentalization is a key feature of biological cells which conduct their metabolic activity in individual steps isolated in distinct, separated compartments. The creation of architectures containing multiple compartments with a structure that resembles that of a biological cell has generated significant research attention and these assemblies are proposed as candidate materials for a range of biomedical applications. In this Review article, the recent successes of multicompartment architectures as carriers for the delivery of therapeutic cargo or the creation of micro- and nanoreactors that mimic metabolic activities, thus acting as artificial cells or organelles, are discussed. The developed technologies to assemble such complex architectures are outlined, the multicompartment carriers' properties which contribute to their performance in diverse applications are discussed, and their successful applications are highlighted. Finally, future directions and developments in the field are suggested.


Asunto(s)
Portadores de Fármacos , Células Artificiales , Nanoestructuras/química
4.
Cell Mol Biol (Noisy-le-grand) ; 56 Suppl: OL1434-41, 2010 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-21062577

RESUMEN

As cholesterol, oxysterols, can insert the cell membrane and thereby modify the functions of membrane-bound proteins. The Na,K-ATPase is very sensitive to its lipid environment, seems to be involved in important endothelial functions as the regulation of nitric oxide (NO) release. The effects of 7-ketocholesterol , an oxysterol present in oxidized LDL, was investigated on Na,K-ATPase in isolated human endothelial cells. Cells were incubated 24h with lecithin-, cholesterol- or 7-ketocholesterol liposomes (6 µg/ml). K+-stimulated paranitrophenyl phosphatase activity, reflecting Na,K-ATPase activity, was evaluated as well as cell viability and lipoperoxidation. The expression of Na,K-ATPase subunits mRNAs and membrane fluidity were also investigated. As Na,K-ATPase and nitric oxide seem to be related, we determined the production of NO and the expression of endothelial NO synthase mRNAs. Na,K-ATPase activity was strongly decreased by 7-ketocholesterol. This decrease, not related to lipoperoxidation, was correlated with a decreased expression of the Na,K-ATPase α1-subunit messengers and with rigidity of plasma membranes. Cholesterol induced similar effects but was less potent than 7-ketocholesterol. Basal NO production and expression of endothelial NO synthase mRNAs were not modified by 7-ketocholesterol. Our new findings demonstrate that 7-ketocholesterol, used at non toxic doses, was very potent to disrupt the transport of ions by Na,K-ATPase and perturb membrane structure. These data demonstrate that 7-ketocholesterol induces endothelial dysfunction without cell death that may contribute to early events in atherosclerosis.


Asunto(s)
Células Endoteliales/enzimología , Cetocolesteroles/farmacología , Fluidez de la Membrana/efectos de los fármacos , ATPasa Intercambiadora de Sodio-Potasio/antagonistas & inhibidores , Supervivencia Celular/efectos de los fármacos , Colesterol/farmacología , Células Endoteliales/efectos de los fármacos , Endotelio Vascular/citología , Humanos , Lecitinas/farmacología , Peroxidación de Lípido/efectos de los fármacos , Óxido Nítrico/metabolismo , Óxido Nítrico Sintasa de Tipo III/genética , Óxido Nítrico Sintasa de Tipo III/metabolismo , Subunidades de Proteína/genética , Subunidades de Proteína/metabolismo , ARN Mensajero/metabolismo , ATPasa Intercambiadora de Sodio-Potasio/genética , ATPasa Intercambiadora de Sodio-Potasio/metabolismo
5.
Cell Mol Biol (Noisy-le-grand) ; 54 Suppl: OL1032-42, 2008 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-18954552

RESUMEN

Dietary antioxidants are frequently proposed as protective agents for the vascular endothelium during the onset of atherosclerosis. This protection may occur at two distinct levels. First, they prevent oxidative modification of atherogenic lipoproteins (LDL). Second, they can provide a cellular protection against oxidized LDL-mediated endothelium dysfunction, although this mechanism remains poorly considered in many instances. To gain insight into the mechanism underlying such cellular protection against oxidized LDL, we examined the impact of a popular traditional medicine, an extract from Ginkgo biloba with well-known antioxidant properties, on two endothelial cells properties: cell adhesion and ionic homeostasis. Cellular lipoperoxides levels were also measured as a marker of cellular oxidative stress. Human umbilical-vein endothelial cells were exposed to native (nat-) or oxidized (ox-) LDL, the latter prepared to be compatible with clinically observed levels of oxidation. Although nat-LDL had little effect, ox-LDL increased endothelial adhesive properties (35%, p<0.01) and lipoperoxidation (45%, p<0.01). Na,K-ATPase activity, a key regulator of ionic homeostasis, was significantly decreased after exposure to nat-LDL (30%, p<0.01) and dramatically depressed after exposure to ox-LDL (65%, p<0.001). The standardized preparation of Ginkgo biloba EGb-761 totally protected adhesive properties and endothelial lipoperoxide levels. Moreover, it limited the decrease in Na,K-ATPase activity induced by ox-LDL to levels similar to nat-LDL. This suggests that EGb-761 protects endothelial adhesive properties and helps prevent the disruption of ionic homeostasis. The EGb-761-mediated inhibition of ox-LDL-induced lipoperoxide levels in endothelial cells appears to be an important mechanism by which Ginkgo biloba extract protects endothelial properties.


Asunto(s)
Endotelio Vascular/efectos de los fármacos , Ginkgo biloba/química , Lipoproteínas LDL/farmacología , Extractos Vegetales/farmacología , Animales , Adhesión Celular/efectos de los fármacos , Línea Celular , Supervivencia Celular , Células Endoteliales/citología , Células Endoteliales/fisiología , Endotelio Vascular/citología , Homeostasis , Humanos , Peroxidación de Lípido , ATPasa Intercambiadora de Sodio-Potasio/metabolismo , Sustancias Reactivas al Ácido Tiobarbitúrico/metabolismo
6.
Cell Mol Biol (Noisy-le-grand) ; 50(7): 809-14, 2004 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-15672465

RESUMEN

The prostate gland is unique in its ability to secrete large amounts of zinc and citrate, suggesting that it employs unusual transport mechanisms. Intracellular ionic homeostasis in prostate is likely to be mediated by the Na,K-pump, yet there have been few studies of its regulation in this tissue. Accordingly, we explored the expression of the Na,K-pump in PC3 cells, an established cell line of human prostate epithelial cells. Total RNA from confluent monolayers of PC3 cells was isolated, reverse transcribed, and the resulting complementary DNA was amplified by polymerase chain reaction using primers specific for each of the pump's constituent subunits. The amplification revealed a complex pattern of Na,K-pump expression, with detection of mRNAs encoding the alpha1-, alpha3-, alpha4-, betal-, beta2- and beta3-isoforms. We next examined the effect on pump activity of prolactin, an important mediator of cell proliferation in prostate cancer. Monolayers exposed to 10 nM prolactin for 24 hr revealed an inhibition of 40% in ouabain-sensitive 86Rb+ uptake, a sensitive measure of pump-mediated transport. These experiments suggest that the unique transport properties of prostate may depend, at least in part, on a complicated pattern of Na,K-pump expression and regulation.


Asunto(s)
Prolactina/farmacología , Neoplasias de la Próstata/enzimología , ATPasa Intercambiadora de Sodio-Potasio/metabolismo , Adenocarcinoma/patología , Transporte Biológico/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Células Epiteliales/enzimología , Humanos , Isoenzimas/química , Isoenzimas/genética , Isoenzimas/metabolismo , Masculino , Ouabaína/farmacología , Neoplasias de la Próstata/patología , ARN Mensajero/genética , Radioisótopos/farmacocinética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Rubidio/farmacocinética , ATPasa Intercambiadora de Sodio-Potasio/química , ATPasa Intercambiadora de Sodio-Potasio/genética , Factores de Tiempo
7.
Cell Mol Biol (Noisy-le-grand) ; 50(7): 869-74, 2004 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-15672472

RESUMEN

Hypertension and diabetes are commonly associated and strongly predispose to renal injuries. In general, antihypertensive therapies protect from these damages, but the effect of cicletanine, a new type of antihypertensive drug, is unknown. This study examines the effects of cicletanine on renal failure in spontaneously hypertensive rats with diabetes (SHRD). Diabetes mellitus was induced with streptozotocin in uninephrectomized SHR. Rats received the vehicle, 10 mg or 50 mg/kg per day of cicletanine for 6 weeks. Age-matched untreated Wistar-Kyoto rats were used as controls. Systolic blood pressure (SBP), microalbuminuria and proteinuria were assessed throughout the treatment. At the end of the study, creatinine clearance measurements and histological analysis of kidneys were performed. Cicletanine did not affect SBP but decreased the elevated albuminuria of diabetic SHR in a dose-dependent manner. Similar results were obtained for proteinuria. Treatment with the high dose of cicletanine also normalized the altered creatinine clearance of diabetic SHR. These results indicate that cicletanine has a renal-protective action, probably blood pressure-independent, in a model combining hypertension and diabetes. The mechanism of renal-protection of cicletanine is not clearly established but may be due to the stimulation of arterial prostacyclin synthesis and/or to the reduction of intraglomerular capillary pressure.


Asunto(s)
Antihipertensivos/farmacología , Diabetes Mellitus Experimental/tratamiento farmacológico , Riñón/efectos de los fármacos , Sustancias Protectoras/uso terapéutico , Piridinas/farmacología , Albuminuria/tratamiento farmacológico , Animales , Presión Sanguínea , Peso Corporal/efectos de los fármacos , Creatinina/sangre , Creatinina/orina , Diabetes Mellitus Experimental/fisiopatología , Relación Dosis-Respuesta a Droga , Riñón/patología , Masculino , Nefrectomía , Proteinuria , Ratas , Ratas Endogámicas SHR , Ratas Endogámicas WKY
9.
Cell Mol Biol (Noisy-le-grand) ; 47(2): 313-8, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11355006

RESUMEN

Fatty acids are known as modulators of the vasoactive properties of the vessel wall and can influence the physical and functional properties of cell membrane. The membrane-bound enzyme Na,K-ATPase plays a central role in endothelial function such as vasoconstriction. In a previous study, we have shown that omega3 fatty acids inhibited Na,K-ATPase activity in human endothelial cells. As Mediterranean diet is known to protect from cardiovascular diseases, we have investigated the effects of Omegacoeur, a Mediterranean nutritional complement consisting of omega3, omega6, omega9 fatty acids, garlic and basil, on Na,K-ATPase activity in human endothelial cells (HUVECs). Cells were incubated for 18 hr with pure lecithin liposomes or Omegacoeur-enriched emulsions (4 mg lecithin/ml). Na,K-ATPase and 5'-nucleotidase activities were determined using coupled assay methods on microsomal fractions obtained from HUVECs. Cell fatty acid composition was evaluated by gas chromatography after extraction of lipids and fatty acids methylation. The results showed that Omegacoeur (0.1 mM) increased Na,K-ATPase activity by 40% without changes in 5'-nucleotidase activity. Cells incubated with Omegacoeur preferentially incorporated linoleic acid. Therefore, linoleic acid or others constituents of Omegacoeur could be responsible of the stimulation of the Na,K-ATPase activity that might be related to changes in endothelial membrane fluidity.


Asunto(s)
Suplementos Dietéticos , Endotelio Vascular/enzimología , Ácidos Grasos/metabolismo , ATPasa Intercambiadora de Sodio-Potasio/metabolismo , 5'-Nucleotidasa/metabolismo , Fraccionamiento Celular , Células Cultivadas , Medio de Cultivo Libre de Suero , Endotelio Vascular/citología , Endotelio Vascular/efectos de los fármacos , Humanos , Liposomas/química , Liposomas/metabolismo , Región Mediterránea , Microsomas/química , Microsomas/metabolismo , Fosfatidilcolinas/química , Fosfatidilcolinas/farmacología
10.
Int J Cardiol ; 78(1): 27-32, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11259810

RESUMEN

A low frequency of ischaemic heart diseases in Eskimos has been related to polyunsaturated fatty acids. We therefore studied fatty acid patterns associated with coronary artery disease (CAD) for a possible relationship between fatty acid profile and CAD diagnosis in Mediterranean patients. The gas chromatography method was used to analyze the membranes of patients' erythrocytes. The patients without coronary stenosis were used as controls. Patients with CAD showed increased percentages of saturated fatty acids (35.8 vs. 34.2%, P<0.001) and monounsaturated fatty acids (14.6 vs. 13.6%, P<0.01), as well as reduced percentages of polyunsaturated fatty acids (38.5 vs. 41.3%, P<0.001). The decrease in polyunsaturated fatty acids percentages was due to the series of n-3 fatty acids (9.2 vs. 11.4%, P<0.001), mainly at the expense of docosahexaenoic acid [C22:6 (n-3)] (4.9+/-0.25% vs. 6.4+/-0.23%, P<0.001) and docosapentaenoic acid [C22:5 (n-3)] (3.0+/-0.19% vs. 3.9+/-0.12%, P<0.001). The study shows altered n-3 fatty acids in Mediterranean patients with CAD. Our data suggest that the percentage of docosahexaenoic and docosapentaenoic acids in erythrocytes could be used as indicators of an independent risk factor for coronary artery disease.


Asunto(s)
Enfermedad Coronaria/sangre , Membrana Eritrocítica/química , Ácidos Grasos/análisis , Adulto , Anciano , Ácidos Grasos Omega-3/análisis , Femenino , Francia , Humanos , Masculino , Persona de Mediana Edad
11.
J Cardiovasc Electrophysiol ; 11(4): 432-8, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10809497

RESUMEN

INTRODUCTION: Ventricular fibrillation induced by either digitalis intoxication or electrical stimulation is reported to alter myocardial energy by impairing the sarcolemmal Na,K-ATPase or the receptor for digitalis and the mitochondrial ATPase synthase or F0F1-ATPase. However, little is known about these membrane functions during atrial fibrillation (AF). METHODS AND RESULTS: We analyzed the effects of electrically induced AF on biochemical activities of atrial F0F1-ATPase and Na,K-ATPase in sheep. A group of six sheep was subjected to direct short electrical stimulation of the right atrium to induce AF. Sham-operated sheep served as a control group. Microsomal and mitochondrial membranes of atrial muscle were isolated and tested for enzymatic activity. All paced sheep developed multiple episodes of sustained AF, with a mean total duration of 110 minutes over a 2-hour period. Data showed that short-term pacing-induced AF significantly activated membrane F0F1-ATPase activity (P < 0.05) without changes in cytochrome-c oxidase activity, Na,K-ATPase activity, ouabain sensitivity, and alpha1-subunit expression. CONCLUSION: Specific activation of F0F1-ATPase activity is an early molecular consequence of sustained AF in sheep.


Asunto(s)
Fibrilación Atrial/enzimología , Atrios Cardíacos/enzimología , Mitocondrias Cardíacas/enzimología , ATPasas de Translocación de Protón/metabolismo , Regulación hacia Arriba , Animales , Fibrilación Atrial/etiología , Biomarcadores , Western Blotting , Membrana Celular/efectos de los fármacos , Membrana Celular/metabolismo , Estimulación Eléctrica/efectos adversos , Complejo IV de Transporte de Electrones/antagonistas & inhibidores , Complejo IV de Transporte de Electrones/metabolismo , Electroforesis en Gel de Poliacrilamida , Inhibidores Enzimáticos , Microsomas/efectos de los fármacos , Microsomas/enzimología , Mitocondrias Cardíacas/efectos de los fármacos , Ouabaína , ATPasas de Translocación de Protón/antagonistas & inhibidores , Ovinos , ATPasa Intercambiadora de Sodio-Potasio/antagonistas & inhibidores , ATPasa Intercambiadora de Sodio-Potasio/metabolismo
12.
J Cardiovasc Electrophysiol ; 11(4): 439-45, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10809498

RESUMEN

INTRODUCTION: Electrical external cardioversion commonly used to treat atrial fibrillation (AF) is associated with myocardial membrane damage and disturbances in ionic homeostasis (hemodynamically unstable). The present study was designed to investigate whether alterations in ionic homeostasis observed were due in part to changes in the myocardial activity of Na,K-ATPase. METHODS AND RESULTS: AF was induced by pacing in ten anesthetized sheep divided into two groups. Group I (n = 4) received a single external countershock of 360 J after three episodes of AF lasting 10 minutes. Group II (n = 6) served as controls. Activity, responsiveness to ouabain, and membrane expression of catalytic alpha and beta subunits of Na,K-ATPase in sarcolemmal myocardial membrane fractions were investigated. Membrane fluidity and fatty acid composition, and plasma levels of atrial natriuretic factor (ANF) also were measured. One shock after episodes of AF significantly decreased ventricular Na,K-ATPase activity up to 50% (P < 0.001) without modification of atrial activity at the membrane level. Sites with low affinity to ouabain showed a fivefold lower affinity for ouabain in the cardioversion group than in the control group (IC50 = 7.9 micromol/L vs 40 micromol/L ouabain, P < 0.05). Plasma levels of ANF were significantly increased in the cardioversion group compared with the control group. These changes were independent of membrane modulation in terms of expression of Na,K-ATPase, membrane fluidity, and fatty acid composition. CONCLUSION: This study suggests that left ventricular perturbation of ionic homeostasis subsequent to transthoracic cardioversion could result from inactivation of Na,K-ATPase activity.


Asunto(s)
Fibrilación Atrial/terapia , Cardioversión Eléctrica , Miocardio/enzimología , ATPasa Intercambiadora de Sodio-Potasio/metabolismo , Animales , Fibrilación Atrial/etiología , Fibrilación Atrial/metabolismo , Factor Natriurético Atrial/sangre , Biomarcadores , Western Blotting , Estimulación Cardíaca Artificial/efectos adversos , Modelos Animales de Enfermedad , Cardioversión Eléctrica/métodos , Electroforesis en Gel de Poliacrilamida , Inhibidores Enzimáticos , Ácidos Grasos/metabolismo , Transporte Iónico/fisiología , Fluidez de la Membrana , Microsomas/enzimología , Ouabaína , Sarcolema/enzimología , Ovinos , ATPasa Intercambiadora de Sodio-Potasio/antagonistas & inhibidores
13.
Can J Vet Res ; 64(2): 88-95, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10805246

RESUMEN

Actinobacillus pleuropneumoniae causes pleuropneumonia in swine. This bacterium secretes proteases that degrade porcine hemoglobin and IgA in vitro. To further characterize A. pleuropneumoniae proteases, we constructed a genomic library expressed in Escherichia coli DH5alpha, and selected a clone that showed proteolytic activity. The recombinant plasmid carries an 800-base pair A. pleuropneumoniae gene sequence that.codes for a 24-kDa polypeptide. A 350-base pair PstI fragment from the sequence hybridized at high stringency with DNA from 12 serotypes of A. pleuropneumoniae, but not with DNA from Actinobacillus suis, Haemophilus parasuis, Pasteurella haemolytica, Pasteurella multocida A or D, or E. coli DH5alpha, thus showing specificity for A. pleuropneumoniae. The expressed polypeptide was recognized as an antigen by convalescent-phase pig sera. Furthermore, a polyclonal antiserum developed against the purified polypeptide recognized an A. pleuropneumoniae oligomeric protein in both crude-extract and cell-free culture media. This recombinant polypeptide cleaved azocoll, gelatin, and actin. Inhibition of the proteolytic activity by diethylpyrocarbonate suggests that this polypeptide is a zinc metalloprotease.


Asunto(s)
Infecciones por Actinobacillus/patología , Actinobacillus pleuropneumoniae/enzimología , Metaloendopeptidasas/metabolismo , Enfermedades de los Porcinos/microbiología , Actinobacillus pleuropneumoniae/clasificación , Actinobacillus pleuropneumoniae/genética , Actinas/metabolismo , Animales , Clonación Molecular , ADN Bacteriano , Biblioteca de Genes , Metaloendopeptidasas/genética , Metaloendopeptidasas/aislamiento & purificación , Plásmidos , Serotipificación , Porcinos , Zinc
14.
Eur J Biochem ; 267(7): 2071-8, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10727947

RESUMEN

Na+/K+-ATPase during diabetes may be regulated by synthesis of its alpha and beta subunits and by changes in membrane fluidity and lipid composition. As these mechanisms were unknown in liver, we studied in rats the effect of streptozotocin-induced diabetes on liver Na+/K+-ATPase. We then evaluated whether fish oil treatment prevented the diabetes-induced changes. Diabetes mellitus induced an increased Na+/K+-ATPase activity and an enhanced expression of the beta1 subunit; there was no change in the amount of the alpha1 and beta3 isoenzymes. Biphasic ouabain inhibition curves were obtained for diabetic groups indicating the presence of low and high affinity sites. No alpha2 and alpha3 isoenzymes could be detected. Diabetes mellitus led to a decrease in membrane fluidity and a change in membrane lipid composition. The diabetes-induced changes are not prevented by fish oil treatment. The results suggest that the increase of Na+/K+-ATPase activity can be associated with the enhanced expression of the beta1 subunit in the diabetic state, but cannot be attributed to changes in membrane fluidity as typically this enzyme will increase in response to an enhancement of membrane fluidity. The presence of a high-affinity site for ouabain (IC50 = 10-7 M) could be explained by the presence of (alphabeta)2 diprotomeric structure of Na+/K+-ATPase or an as yet unknown alpha subunit isoform that may exist in diabetes mellitus. These stimulations might be related, in part, to the modification of fatty acid content during diabetes.


Asunto(s)
Diabetes Mellitus Experimental/enzimología , Isoenzimas/metabolismo , Hígado/enzimología , ATPasa Intercambiadora de Sodio-Potasio/metabolismo , Animales , Secuencia de Bases , Glucemia/análisis , Peso Corporal , Cartilla de ADN , Diabetes Mellitus Experimental/sangre , Inhibidores Enzimáticos/farmacología , Ácidos Grasos/metabolismo , Isoenzimas/antagonistas & inhibidores , Hígado/metabolismo , Masculino , Lípidos de la Membrana/metabolismo , Ouabaína/farmacología , Ratas , Ratas Sprague-Dawley , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , ATPasa Intercambiadora de Sodio-Potasio/antagonistas & inhibidores , Estreptozocina
15.
J Histochem Cytochem ; 47(6): 809-16, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10330457

RESUMEN

Because diabetes causes alterations in hepatic membrane fatty acid content, these changes may affect the Na+,K+-ATPase. In this study we documented the effects of streptozotocin (STZ)-induced diabetes on hepatic Na+,K+-ATPase catalytic alpha1-subunit and evaluated whether these changes could be normalized by fish oil supplementation. Two groups of diabetic rats received fish oil or olive oil supplementation. Both groups had a respective control group. We studied the localization of catalytic alpha1-subunit on bile canalicular and basolateral membranes using immunocytochemical methods and confocal laser scanning microscopy, and the Na+, K+-ATPase activity, membrane fluidity, and fatty acid composition on isolated hepatic membranes. A decrease in the alpha1-subunit was observed with diabetes in the bile canalicular membranes, without changes in basolateral membranes. This decrease was partially prevented by dietary fish oil. Diabetes induces significant changes as documented by enzymatic Na+,K+-ATPase activity, membrane fluidity, and fatty acid content, whereas little change in these parameters was observed after a fish oil diet. In conclusion, STZ-induced diabetes appears to modify bile canalicular membrane integrity and dietary fish oil partly prevents the diabetes-induced alterations.


Asunto(s)
Diabetes Mellitus Experimental/enzimología , Aceites de Pescado/uso terapéutico , Hígado/enzimología , ATPasa Intercambiadora de Sodio-Potasio/metabolismo , Animales , Membrana Celular/química , Membrana Celular/enzimología , Membrana Celular/fisiología , Diabetes Mellitus Experimental/dietoterapia , Ácidos Grasos/análisis , Procesamiento de Imagen Asistido por Computador , Inmunohistoquímica , Masculino , Ratas , Ratas Sprague-Dawley
16.
Atherosclerosis ; 142(2): 327-33, 1999 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10030384

RESUMEN

We have investigated the effects of cholesterol and omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexenoic acid (DHA) on Na, K-ATPase activity in human endothelial cells (HUVEC). Cultured HUVEC were incubated for 18 h with pure egg phosphatidylcholine (PC), or cholesterol-enriched liposomes (4 mg PC/ml). EPA and DHA alpha-tocopherol-acetate were emulsified with PC and incubated with HUVEC (10 mM). Na, K-ATPase and 5'-nucleotidase activities were determined using the coupled assay method on microsomal fractions obtained from cultured cells using non treated cells as control. Cholesterol enrichment significantly reduced both Na, K-ATPase and 5'-nucleotidase activities by a similar level (- 40%), whereas pure phospholipid liposomes inhibited this activity only by 22%. The dose-response curves of Na, K-ATPase activity were all biphasic assuming the presence of two independent sites exhibiting different affinities for ouabain of nM and microM respectively. The cholesterol induced inhibitory effect was greater for low affinity sites (-54%) as compared to that of the high affinity sites (-24%) whereas omega-3 fatty acids reduced the activity of both sites by 22%. Short term effects of EPA and DHA on Na, K-ATPase activity were determined by incubating microsomal fractions from untreated cells with various concentrations of free fatty acids (from 1 to 200 microM) for 20 min. Both EPA and DHA significantly reduced Na, K-ATPase activity but inhibition by EPA seems to be more effective than DHA. These results suggest that cholesterol and omega-3 fatty acids reduce Na, K-ATPase activity in HUVEC.


Asunto(s)
Colesterol/farmacología , Endotelio Vascular/enzimología , Ácidos Grasos Omega-3/farmacología , ATPasa Intercambiadora de Sodio-Potasio/antagonistas & inhibidores , Membrana Celular/efectos de los fármacos , Membrana Celular/enzimología , Membrana Celular/ultraestructura , Células Cultivadas , Ácidos Docosahexaenoicos/farmacología , Relación Dosis-Respuesta a Droga , Ácido Eicosapentaenoico/farmacología , Endotelio Vascular/citología , Endotelio Vascular/efectos de los fármacos , Inhibidores Enzimáticos/farmacología , Humanos , Microsomas/efectos de los fármacos , Microsomas/enzimología , Microsomas/ultraestructura , Ouabaína/farmacología , ATPasa Intercambiadora de Sodio-Potasio/metabolismo , Ultracentrifugación , Venas Umbilicales/citología , Venas Umbilicales/efectos de los fármacos , Venas Umbilicales/enzimología
17.
Rev Enferm ; 21(237): 65-9, 1998 May.
Artículo en Español | MEDLINE | ID: mdl-9653340

RESUMEN

The nursing personnel at the C.H. Xeral-Cíes participated in a study of various types of self-protection methods over two time spans. The hypotheses investigated were the following: 1. Is there a divergence in the percentage of personnel vaccinated against hepatitis B?, 2. Is there an increase in the level of knowledge about universal precautions?, and 3. Is there any improvement in self-protection methods in the latter study? The statistical analysis used has a variable range of < 0.05. The results indicated significant differences in the percentage of personnel vaccinated against hepatitis B, in knowledge about universal precautions, and in the number of accidental punctures reported to the Preventative Medicine Service.


Asunto(s)
Conocimientos, Actitudes y Práctica en Salud , Control de Infecciones/métodos , Personal de Enfermería/educación , Personal de Enfermería/psicología , Salud Laboral , Autocuidado , Autocuidado/métodos , Estudios Transversales , Humanos , Lesiones por Pinchazo de Aguja/prevención & control , Autocuidado/psicología , Encuestas y Cuestionarios , Precauciones Universales , Vacunación
18.
Am J Med ; 76(1): 151-4, 1984 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-6691353

RESUMEN

A 24-year-old woman presented with clinical features suggesting hypoparathyroidism: tetany, basal ganglia calcification, and a history of a seizure disorder. Hypocalcemia was present on admission despite therapy with calcium and vitamin D. Hormonal evaluation revealed undetectable parathormone levels and a normal cyclic AMP and phosphaturic response to parathormone infusion, suggesting the diagnosis of idiopathic hypoparathyroidism. Additional testing, however, revealed hypomagnesemia and elevated urinary magnesium levels. Normomagnesemia could not be consistently achieved despite oral magnesium administration. When the serum magnesium level was temporarily normalized via intravenous magnesium supplementation, parathormone levels rose into the normal range. These data indicate that the patient's hypomagnesemia was most likely due to renal magnesium loss. The normalization of her parathormone level during magnesium replenishment, along with the parathormone infusion data, suggests that this patient's hypomagnesemia was responsible for decreased parathormone synthesis and/or secretion, while target tissue responsiveness to parathormone was maintained.


Asunto(s)
Hipoparatiroidismo/etiología , Enfermedades Renales/fisiopatología , Magnesio/sangre , Hormona Paratiroidea/metabolismo , Adulto , Calcio/sangre , Femenino , Humanos , Hipocalcemia/etiología , Hipoparatiroidismo/fisiopatología , Deficiencia de Magnesio/complicaciones , Hormona Paratiroidea/sangre
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