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1.
Rev. clín. esp. (Ed. impr.) ; 219(2): 84-89, mar. 2019. graf
Artículo en Español | IBECS | ID: ibc-185704

RESUMEN

La disminución significativa y progresiva en el número de profesores permanentes en las facultades de Medicina (catedrático, profesor titular y profesor contratado doctor) es motivo de preocupación para la Conferencia Nacional de Decanos. Esta disminución se intensificará en la próxima década (2017-2026). Se jubilará el 43% del profesorado permanente: un 55% del profesorado vinculado de áreas clínicas, un 34% del profesorado no vinculado de áreas clínicas y un 32% del profesorado de áreas básicas. Este déficit es importante en el momento actual y en pocos años la situación será insostenible, especialmente en áreas clínicas. Este informe pone de manifiesto la necesidad inaplazable de adoptar medidas urgentes que palíen la situación actual y que prevengan un mal mayor. La formación de los futuros médicos, responsables inmediatos de salud de nuestra sociedad, depende en gran parte de la enseñanza teórica y práctica que se imparte en las facultades de Medicina, con la colaboración esencial de las instituciones sanitarias. Paradójicamente, a la vez que disminuye sustancialmente el número de profesores, aumenta exponencialmente el número de facultades de Medicina y el número de alumnos que se admiten cada año sin justificación académica ni sanitaria


The significant and progressive reduction in the number of permanent teachers in medical schools (professor, associate professor and assistant professor) is a reason for concern for the National Conference of Deans. This reduction will intensify in the coming decade (2017-2026). Forty-three percent of the permanent faculty will retire, as will 55% of the faculty linked to clinical areas, 34% of the faculty not linked to clinical areas and 32% of the faculty of basic areas. This deficit is significant now, and, in a few years, the situation will be unsustainable, especially in the clinical areas. This report reveals the pressing need to adopt urgent measures to alleviate the present situation and prevent a greater problem. The training of future physicians, immediately responsible for the health of our society, depends largely on the theoretical and practical training taught in medical schools, with the essential collaboration of healthcare institutions. Paradoxically, while the number of teachers decreases substantially, there is an exponential increase in the number of medical schools and students who are admitted every year without academic or healthcare justification


Asunto(s)
Humanos , Docentes Médicos/tendencias , Educación Médica/tendencias , Facultades de Medicina/estadística & datos numéricos , Formación del Profesorado/tendencias
2.
Rev Clin Esp (Barc) ; 219(2): 84-89, 2019 Mar.
Artículo en Inglés, Español | MEDLINE | ID: mdl-29887248

RESUMEN

The significant and progressive reduction in the number of permanent teachers in medical schools (professor, associate professor and assistant professor) is a reason for concern for the National Conference of Deans. This reduction will intensify in the coming decade (2017-2026). Forty-three percent of the permanent faculty will retire, as will 55% of the faculty linked to clinical areas, 34% of the faculty not linked to clinical areas and 32% of the faculty of basic areas. This deficit is significant now, and, in a few years, the situation will be unsustainable, especially in the clinical areas. This report reveals the pressing need to adopt urgent measures to alleviate the present situation and prevent a greater problem. The training of future physicians, immediately responsible for the health of our society, depends largely on the theoretical and practical training taught in medical schools, with the essential collaboration of healthcare institutions. Paradoxically, while the number of teachers decreases substantially, there is an exponential increase in the number of medical schools and students who are admitted every year without academic or healthcare justification.

3.
Biochim Biophys Acta Gen Subj ; 1862(5): 1157-1167, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29452236

RESUMEN

BACKGROUND: Intrauterine growth restriction (IUGR) is associated with cardiovascular remodeling persisting into adulthood. Mitochondrial bioenergetics, essential for embryonic development and cardiovascular function, are regulated by nuclear effectors as sirtuins. A rabbit model of IUGR and cardiovascular remodeling was generated, in which heart mitochondrial alterations were observed by microscopic and transcriptomic analysis. We aimed to evaluate if such alterations are translated at a functional mitochondrial level to establish the etiopathology and potential therapeutic targets for this obstetric complication. METHODS: Hearts and placentas from 16 IUGR-offspring and 14 controls were included to characterize mitochondrial function. RESULTS: Enzymatic activities of complexes II, IV and II + III in IUGR-hearts (-11.96 ±â€¯3.16%; -15.58 ±â€¯5.32%; -14.73 ±â€¯4.37%; p < 0.05) and II and II + III in IUGR-placentas (-17.22 ±â€¯3.46%; p < 0.005 and -29.64 ±â€¯4.43%; p < 0.001) significantly decreased. This was accompanied by a not significant reduction in CI-stimulated oxygen consumption and significantly decreased complex II SDHB subunit expression in placenta (-44.12 ±â€¯5.88%; p < 0.001). Levels of mitochondrial content, Coenzyme Q and cellular ATP were conserved. Lipid peroxidation significantly decreased in IUGR-hearts (-39.02 ±â€¯4.35%; p < 0.001), but not significantly increased in IUGR-placentas. Sirtuin3 protein expression significantly increased in IUGR-hearts (84.21 ±â€¯31.58%; p < 0.05) despite conserved anti-oxidant SOD2 protein expression and activity in both tissues. CONCLUSIONS: IUGR is associated with cardiac and placental mitochondrial CII dysfunction. Up-regulated expression of Sirtuin3 may explain attenuation of cardiac oxidative damage and preserved ATP levels under CII deficiency. GENERAL SIGNIFICANCE: These findings may allow the design of dietary interventions to modulate Sirtuin3 expression and consequent regulation of mitochondrial imbalance associated with IUGR and derived cardiovascular remodeling.


Asunto(s)
Retardo del Crecimiento Fetal/metabolismo , Mitocondrias Cardíacas/metabolismo , Proteínas Mitocondriales/biosíntesis , Placenta/metabolismo , Sirtuina 3/biosíntesis , Animales , Modelos Animales de Enfermedad , Femenino , Retardo del Crecimiento Fetal/patología , Mitocondrias Cardíacas/patología , Placenta/patología , Embarazo , Conejos
4.
Artículo en Inglés | MEDLINE | ID: mdl-28674062

RESUMEN

The antibiotic linezolid is a ribosomal inhibitor with excellent efficacy. Although the administration period has been reduced to 28 days, side effects, usually of hematologic or neuropathic origin, are still reported due to secondary inhibition of mitochondrial protein synthesis. Susceptibility to linezolid toxicity remains unknown. Therefore, the objective of this study was to gain an understanding of clinical heterogeneity in response to identical linezolid exposures through exhaustive examination of the molecular basis of tissue-dependent mitotoxicity, consequent cell dysfunction, and the association of mitochondrial genetics with adverse effects of linezolid administered for the recommended period. Peripheral blood mononuclear cells (PBMC) and skin nerve fibers from 19 and 6 patients, respectively, were evaluated before and after a 28-day linezolid treatment in order to assess toxic effects on mitochondria and cells. Mitochondrial DNA haplotypes and single nucleotide polymorphisms (SNPs) in ribosomal sequences where linezolid binds to mitochondrial ribosomes were also analyzed to investigate their genetic contributions. We found that linezolid reduced mitochondrial protein levels, complex IV activity, and mitochondrial mass in PBMC and was associated with a trend toward an increase in the rate of apoptosis. In skin tissue, mitochondrial mass increased within nerve fibers, accompanied by subclinical axonal swelling. Mitochondrial haplogroup U, mutations in 12S rRNA, and the m.2706A→G, m.3197T→C, and m.3010G→A polymorphisms in 16S rRNA showed a trend toward an association with increased mitochondrial and clinical adverse effects. We conclude that even when linezolid is administered for a shorter time than formerly, adverse effects are reported by 63% of patients. Linezolid exerts tissue-dependent mitotoxicity that is responsible for downstream cellular consequences (blood cell death and nerve fiber swelling), leading to adverse hematologic and peripheral nervous side effects. Multicentric studies should confirm genetic susceptibility in larger cohorts.


Asunto(s)
Antibacterianos/toxicidad , Ciclooxigenasa 2/metabolismo , Leucocitos Mononucleares/efectos de los fármacos , Linezolid/toxicidad , Mitocondrias/efectos de los fármacos , Fibras Nerviosas/efectos de los fármacos , Inhibidores de la Síntesis de la Proteína/toxicidad , Canales Aniónicos Dependientes del Voltaje/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Complejo IV de Transporte de Electrones/metabolismo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mitocondrias/genética , Proteínas Mitocondriales/metabolismo , Polimorfismo de Nucleótido Simple/genética , ARN Ribosómico/genética , ARN Ribosómico 16S/genética , Piel/citología , Piel/inervación
5.
Parkinsons Dis ; 2017: 9816095, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28660090

RESUMEN

OBJECTIVE: To determine potential mitochondrial and oxidative alterations in colon biopsies from idiopathic REM sleep behavior disorder (iRBD) and Parkinson's disease (PD) subjects. METHODS: Colonic biopsies from 7 iRBD subjects, 9 subjects with clinically diagnosed PD, and 9 healthy controls were homogenized in 5% w/v mannitol. Citrate synthase (CS) and complex I (CI) were analyzed spectrophotometrically. Oxidative damage was assessed either by lipid peroxidation, through malondialdehyde and hydroxyalkenal content by spectrophotometry, or through antioxidant enzyme levels of superoxide dismutase-2 (SOD2), glutathione peroxidase-1 (Gpx1), and catalase (CAT) by western blot. The presence of mitochondrial DNA (mtDNA) deletions was assessed by long PCR and electrophoresis. RESULTS: Nonsignificant trends to CI decrease in both iRBD (45.69 ± 18.15; 23% decrease) and PD patients (37.57 ± 12.41; 37% decrease) were found compared to controls (59.51 ± 12.52, p: NS). Lipid peroxidation was maintained among groups (iRBD: 27.46 ± 3.04, PD: 37.2 ± 3.92, and controls: 31.71 ± 3.94; p: NS). Antioxidant enzymes SOD2 (iRBD: 2.30 ± 0.92, PD: 1.48 ± 0.39, and controls: 1.09 ± 0.318) and Gpx1 (iRBD 0.29 ± 0.12, PD: 0.56 ± 0.33, and controls: 0.38 ± 0.16) did not show significant differences between groups. CAT was only detected in 2 controls and 1 iRBD subject. One iRBD patient presented a single mtDNA deletion.

6.
J Antimicrob Chemother ; 70(8): 2330-6, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25921514

RESUMEN

OBJECTIVES: Ex vivo analysis of mitochondrial function may reveal HIV progression and the impact of ART. We propose a mitochondrial and apoptotic in vitro model using Jurkat T cells incubated with plasma. The objectives of this study were to evaluate mitochondrial and apoptotic lesions in this model in relation to HIV progression, and to assess the effect of >1 year of standard non-thymidine-containing therapy. METHODS: This was a cross-sectional comparison among three age- and gender-matched groups (n = 19 × 3): healthy non-HIV-infected participants, HIV-infected long-term non-progressors (LTNPs) and standard antiretroviral-naive chronically infected patients [standard progressors (Sps)], longitudinally evaluated before (Sp1) and after (Sp2) >1 year of efavirenz + tenofovir + emtricitabine therapy. We analysed mitochondrial DNA content by RT-PCR, mitochondrial function by spectrophotometry, mitochondrial protein synthesis by western blot analysis, mitochondrial dynamics by western blot analysis (MFN2), apoptotic transition pore formation by western blot analysis (VDAC-1) and mitochondrial membrane potential and annexin V/propidium iodide fluorescence by flow cytometry. RESULTS: There was a decreasing non-significant trend towards lower mitochondrial parameters for HIV-infected values with respect to uninfected control reference values. HIV progression (LTNP versus Sp1) was associated with decreased mitochondrial genetic, functional and translational parameters, which partially recovered after treatment intervention (Sp2). Mitochondrial fusion showed a trend to decrease non-significantly in Sp patients compared with LTNP patients, especially after therapy. All apoptotic parameters showed a trend to increase in Sp1 with respect to LTNP, followed by recovery in Sp2. CONCLUSIONS: We proposed an in vitro model for mitochondrial and apoptotic assessment to test the effects of HIV infection and its therapy, resembling in vivo conditions. This model could be useful for clinical research purposes.


Asunto(s)
Antirretrovirales/administración & dosificación , Antirretrovirales/efectos adversos , Apoptosis , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/patología , Mitocondrias/efectos de los fármacos , Adulto , Estudios Transversales , Progresión de la Enfermedad , Femenino , Infecciones por VIH/virología , VIH-1/aislamiento & purificación , Humanos , Células Jurkat , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Mitocondrias/fisiología
7.
BMJ ; 343: d6783, 2011 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-22108262

RESUMEN

OBJECTIVE: To investigate the effect of an additional review based on reporting guidelines such as STROBE and CONSORT on quality of manuscripts. DESIGN: Masked randomised trial. Population Original research manuscripts submitted to the Medicina Clínica journal from May 2008 to April 2009 and considered suitable for publication. CONTROL GROUP: conventional peer reviews alone. Intervention group: conventional review plus an additional review looking for missing items from reporting guidelines. Outcomes Manuscript quality, assessed with a 5 point Likert scale (primary: overall quality; secondary: average quality of specific items in paper). Main analysis compared groups as allocated, after adjustment for baseline factors (analysis of covariance); sensitivity analysis compared groups as reviewed. Adherence to reviewer suggestions assessed with Likert scale. RESULTS: Of 126 consecutive papers receiving conventional review, 34 were not suitable for publication. The remaining 92 papers were allocated to receive conventional reviews alone (n=41) or additional reviews (n=51). Four papers assigned to the conventional review group deviated from protocol; they received an additional review based on reporting guidelines. We saw an improvement in manuscript quality in favour of the additional review group (comparison as allocated, 0.25, 95% confidence interval -0.05 to 0.54; as reviewed, 0.33, 0.03 to 0.63). More papers with additional reviews than with conventional reviews alone improved from baseline (22 (43%) v eight (20%), difference 23.6% (3.2% to 44.0%), number needed to treat 4.2 (from 2.3 to 31.2), relative risk 2.21 (1.10 to 4.44)). Authors in the additional review group adhered more to suggestions from conventional reviews than to those from additional reviews (average increase 0.43 Likert points (0.19 to 0.67)). CONCLUSIONS: Additional reviews based on reporting guidelines improve manuscript quality, although the observed effect was smaller than hypothesised and not definitively demonstrated. Authors adhere more to suggestions from conventional reviews than to those from additional reviews, showing difficulties in adhering to high methodological standards at the latest research phases. To boost paper quality and impact, authors should be aware of future requirements of reporting guidelines at the very beginning of their study. Trial registration and protocol Although registries do not include trials of peer review, the protocol design was submitted to sponsored research projects (Instituto de Salud Carlos III, PI081903).


Asunto(s)
Guías como Asunto , Revisión de la Investigación por Pares , Publicaciones Periódicas como Asunto , Autoria/normas , Control de Calidad , Reproducibilidad de los Resultados
9.
Artículo en Inglés | MEDLINE | ID: mdl-21424975

RESUMEN

The best oxygen therapy for acute carbon monoxide poisoning (ACOP) remains unestablished. Reported mitochondrial complex IV (mtCIV) inhibition, together with carboxyhaemoglobin (COHb)-induced hypoxia, may influence acute clinical symptoms and outcome. To "mitochondrially" evaluate treatment efficacy, we correlated intoxication severity and symptoms with mitochondrial function (mtCIV activity) and oxidative stress (lipid peroxidation) in 60 poisoned patients and determined ACOP recovery depending on either normobaric or hyperbaric oxygen therapy along a 3-month follow-up. In the present article we positively evaluate mtCIV as a good marker of ACOP recovery, treatment effectiveness, and late neurological syndrome development, which advocates for hyperbaric oxygen therapy as the treatment of choice. However, we discourage its usefulness as a severity marker because of its excessive sensitivity. We additionally evaluate oxidative stress role and prognostic factors for neurological sequelae development.


Asunto(s)
Contaminantes Atmosféricos/toxicidad , Intoxicación por Monóxido de Carbono/terapia , Monóxido de Carbono/toxicidad , Mitocondrias/efectos de los fármacos , Terapia por Inhalación de Oxígeno , Enfermedad Aguda , Adolescente , Adulto , Biomarcadores/metabolismo , Intoxicación por Monóxido de Carbono/diagnóstico , Intoxicación por Monóxido de Carbono/metabolismo , Complejo IV de Transporte de Electrones/antagonistas & inhibidores , Complejo IV de Transporte de Electrones/metabolismo , Femenino , Humanos , Peroxidación de Lípido/efectos de los fármacos , Masculino , Estrés Oxidativo , Resultado del Tratamiento , Adulto Joven
10.
Rev. toxicol ; 25(1/3): 69-72, 2008. ilus
Artículo en Español | IBECS | ID: ibc-77908

RESUMEN

La intoxicación por monóxido de carbono (CO) es una patología frecuente en los Servicios de Urgencias que muchas veces no se diagnostica debido a la presentación clínica inespecífica, a la baja disponibilidad de co-oxímetros en los Laboratorios de Urgencias y a las características propias del gas (incoloro, inodoro y noirritante). El CO es un gas producido por la combustión incompleta de la materia orgánica, que se une a la hemoglobina, dificultando el transporte de oxígeno a los tejidos, y a la citocromo-oxidasa, generando una disfunción multiorgánica, en particular sobre el SNC. La afectación cardiovascular es menos frecuente y es un riesgo menos conocido entre los sanitarios, por lo que nos parece de interés presentar un caso de síndrome coronario agudo asociado a una intoxicación grave por CO (AU)


Carbon monoxide (CO) poisoning is a frequent pathology in Emergency Departments (ED) that many times it is not diagnosed due to the lack of a specific clinical presentation, and thelack of co-oximeters in the ED as well as the gas ‘own characteristics(odorless, colorless and non irritating). CO is produced by the in complete combustion of organic materia, it binds to hemoglobin, impairing oxygen transport trough out the tissues and the cytocromeoxidase, thus generating a multiorganic disfunction, particularly over the Central Nervous System. Cardiovascular involvement is less frequent and is a less known risk by sanitary personnel, the reason why it is of special interest to present a case of acute coronary syndrome associated to severe CO intoxication (AU)


Asunto(s)
Humanos , Intoxicación por Monóxido de Carbono/complicaciones , Enfermedad Coronaria/etiología , Índice de Severidad de la Enfermedad , Enfermedad Aguda
11.
Eur Respir J ; 23(2): 214-8, 2004 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-14979494

RESUMEN

Smoking causes a decrease of mitochondrial complex IV activity in chronic smokers. However, it is not known if this toxic effect is due to the acute effect of cigarette smoke itself or is a secondary phenomenon related to other smoking factors. The study assessed mitochondrial respiratory chain function in peripheral blood mononuclear cells of 15 healthy nonsmoker individuals before smoking (t0), immediately after smoking five cigarettes in 45 min (t1) and 24 h later (t2). Blood carboxyhaemoglobin (COHb) and carbon monoxide concentrations in exhaled air (COEA) were determined to ascertain smoke inhalation status. After acute smoking, COHb increased from 0.5 +/- 0.3% to 3.3 +/- 1.5%, and COEA from 2.9 +/- 2.5 to 26.1 +/- 9.9 ppm. Complex II and III enzyme activities did not change along the study. Complex IV activity showed a 23% inhibition at t1 but returned to initial (to) levels at t2. A decay in oxygen consumption was observed after the correction for mitochondrial content. Lipid peroxidation of cell membranes remained unchanged. Short-time smoking causes an acute and reversible mitochondrial complex IV inhibition in human mononuclear cells. These results suggest that smoke itself is one of the causes for the decrease of complex IV activity observed in chronic smokers.


Asunto(s)
Complejo IV de Transporte de Electrones/antagonistas & inhibidores , Fumar/efectos adversos , Adulto , Monóxido de Carbono/sangre , Carboxihemoglobina/metabolismo , Transporte de Electrón/fisiología , Femenino , Humanos , Peroxidación de Lípido/fisiología , Linfocitos/enzimología , Masculino , Monocitos/enzimología , Consumo de Oxígeno/fisiología , Fumar/fisiopatología
12.
Diabetologia ; 46(10): 1394-401, 2003 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-13680126

RESUMEN

AIMS/HYPOTHESIS: The electrons of the glycolysis-derived reduced form of NADH are transferred to mitochondria through the NADH shuttle system. There are two NADH shuttles: the glycerol phosphate and malate-aspartate shuttle. Mice with a targeted disruption of mitochondrial glycerol-3-phosphate dehydrogenase, a rate-limiting enzyme of the glycerol phosphate shuttle, are not diabetic and have normal islet glucose-induced secretion. In this study, we analyzed if environmental factors, such as a high carbohydrate diet could contribute to the development of Type 2 diabetes mellitus in mice with a specific defective genetic background. METHODS: The mice were fed with a high carbohydrate diet for 1 and 6 months, and several biochemical parameters were analysed. The mitochondrial respiratory activity was assayed by polarography; and the islet function was studied by islet perifusion and pancreas perfusion. RESULTS: The high carbohydrate diet induced hyperglycaemia, hyperinsulinaemia, and islet hyperplasia in the wild-type and heterozygote mice. Activity of the respiratory chain complex I also increased in these mice. In contrast, these effects were not observed in the null mice fed with the diet; in addition, these null mice had an increased insulin sensitivity compared to wild-type mice. CONCLUSION/INTERPRETATION: The phenotype of the mice with an impairment of NADH shuttles does not worsen when fed a high carbohydrate diet; moreover, the diet does not compromise islet function.


Asunto(s)
Diabetes Mellitus Tipo 2/etiología , Carbohidratos de la Dieta/administración & dosificación , Glicerolfosfato Deshidrogenasa/deficiencia , Hiperglucemia/etiología , Mitocondrias/enzimología , Animales , Glucemia/análisis , Respiración de la Célula/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Islotes Pancreáticos/efectos de los fármacos , Islotes Pancreáticos/metabolismo , Lípidos/sangre , Ratones , Ratones Noqueados , Mitocondrias/fisiología , Factores de Tiempo
13.
J Neurol Sci ; 206(1): 23-6, 2003 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-12480080

RESUMEN

Electron transport chain (ETC) dysfunction has been claimed to contribute to the expression of neurodegenerative disorders. We have investigated the effects of the treatment with rivastigmine, a commonly used cholinesterase inhibitor, on lymphocyte mitochondria of patients with Alzheimer's disease (AD). Increased enzymatic activities of diverse complexes and oxidative capacity of the ETC were found. Enhanced mitochondrial ETC function may contribute to the beneficial effects of rivastigmine on clinical manifestations of AD.


Asunto(s)
Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/metabolismo , Carbamatos/uso terapéutico , Inhibidores de la Colinesterasa/uso terapéutico , Linfocitos/metabolismo , Mitocondrias/metabolismo , Fenilcarbamatos , Anciano , Transporte de Electrón/efectos de los fármacos , Femenino , Humanos , Linfocitos/efectos de los fármacos , Masculino , Mitocondrias/efectos de los fármacos , Fármacos Neuroprotectores/uso terapéutico , Valores de Referencia , Rivastigmina
15.
AIDS ; 15(13): 1643-51, 2001 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-11546938

RESUMEN

OBJECTIVES: The management of HIV infection has greatly improved during recent years essentially because of the appearance of new antiretroviral drugs. Highly active antiretroviral therapy (HAART) has achieved important reductions of viraemia and significant recoveries of CD4(+) cell counts in HIV-infected patients. Nonetheless, cases of HIV-infected individuals experiencing lipodystrophy (LD) are being increasingly reported. The purpose of this work was to analyse whether the presence of mitochondrial abnormalities is a frequent feature in LD, since we previously detected mitochondrial abnormalities in an HIV-patient. The second main objective was to study whether LD could be associated with a specific drug. DESIGN: Seven HIV patients presenting LD and five HIV non-LD controls participated in the study. LD patients met the following criteria: (1) LD was their only clinical abnormality, (2) LD was clinically relevant, (3) compliance with antiretroviral treatment was higher than 90% and (4) patients did not have personal or familial history suggestive of mitochondrial disease or neuromuscular disorder. METHODS: Histological stainings, histo-enzymatic reactions, enzymatic and respiratory activities of mitochondrial respiratory chain complexes, and mitochondrial DNA (mtDNA) depletion and rearrangements were examined on muscle mitochondria. RESULTS: Structural muscle abnormalities, mitochondrial respiratory chain dysfunction or mtDNA deletions were detected in all HIV lipodystrophic patients. CONCLUSIONS: The mitochondrial abnormalities found suggest that mitochondrial dysfunction could play a role in the development of antiretroviral therapy-related lipodystrophy.


Asunto(s)
Terapia Antirretroviral Altamente Activa/efectos adversos , Infecciones por VIH/tratamiento farmacológico , Lipodistrofia/inducido químicamente , Mitocondrias Musculares/metabolismo , Mitocondrias Musculares/ultraestructura , Adulto , Anciano , ADN Mitocondrial/genética , ADN Mitocondrial/metabolismo , Femenino , Eliminación de Gen , Infecciones por VIH/complicaciones , VIH-1 , Humanos , Lipodistrofia/metabolismo , Lipodistrofia/patología , Masculino , Persona de Mediana Edad , Músculo Esquelético/metabolismo , Músculo Esquelético/ultraestructura
16.
Arthritis Rheum ; 44(6): 1387-95, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11407699

RESUMEN

OBJECTIVE: Occasionally, a temporal artery biopsy reveals small-vessel vasculitis (SVV) surrounding a spared temporal artery, the significance of which is unclear. We analyzed the final diagnosis in a series of patients with this condition and tried to identify histopathologic features with potential usefulness in predicting the ultimate diagnosis. METHODS: We performed a clinical and histopathologic review of 28 patients in whom SVV surrounding a spared temporal artery was the first histologic finding that led to the diagnosis of vasculitis. For comparison purposes, we analyzed the pattern of small vessel involvement in 30 patients with biopsy-proven giant cell arteritis (GCA). RESULTS: GCA was considered the most likely diagnosis in 12 patients, based on the absence of clinical evidence of additional organ involvement and normal findings on muscle biopsy and electrophysiologic study. Three patients had systemic necrotizing vasculitis (SNV), based on the demonstration of typical lesions on subsequent muscle, nerve, or kidney biopsy. After extensive evaluation, 4 patients remained unclassifiable. Nine patients were incompletely studied. Fibrinoid necrosis was significantly more frequent in patients with SNV (P = 0.0022), whereas involvement of vasa vasorum was more frequent in patients classified as having GCA (P = 0.022). No differences in the pattern of small vessel involvement were found in patients with SVV surrounding a spared temporal artery who were classified as having GCA compared with patients with biopsy-proven GCA. Granulocytes were observed at similar frequency in all conditions. CONCLUSION: SVV may be the only abnormal feature in a temporal artery biopsy and the only histologic evidence of vasculitis. The diagnosis of GCA can be reasonably established in most of these patients when there is no apparent evidence of additional organ involvement. However, when fibrinoid necrosis is observed or the temporal artery vasa vasorum are not involved, SNV must be extensively excluded.


Asunto(s)
Arteritis de Células Gigantes/patología , Lectinas de Plantas , Arterias Temporales/patología , Adulto , Anciano , Anciano de 80 o más Años , Endotelio Vascular/metabolismo , Endotelio Vascular/patología , Femenino , Granulocitos/enzimología , Humanos , Técnicas para Inmunoenzimas , Lectinas/metabolismo , Masculino , Persona de Mediana Edad , Elastasa Pancreática/análisis , Estudios Retrospectivos
18.
Cardiovasc Res ; 47(3): 624-31, 2000 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-10963736

RESUMEN

BACKGROUND: Aging is associated with increased oxidative damage at multiple cellular and tissular levels. A decrease in mitochondrial function has repeatedly been advocated as a primary key event, especially on the basis of analysis of skeletal muscle mitochondria. However, some doubts on this issue have arisen when confounding variables (such as physical activity or smoking habit) have been taken into account in the analysis of mitochondrial respiratory chain (MRC) enzyme activities or when additional analytical parameters such as enzyme ratios have been considered. OBJECTIVE: To determine whether oxidative damage and enzyme activities of the MRC are influenced by the aging process in human hearts. PATIENTS AND METHODS: We studied cardiac muscle obtained from 59 organ donors (age: 56+/-12 years, 75% men). Oxidative membrane damage was evaluated through the assessment of lipid peroxidation. Absolute and relative enzyme activities (AEA and REA, respectively) of complex I, II, III and IV of the MRC were spectrophotometrically measured. Stoichiometric relationships among MRC complexes were also assessed through calculating MRC ratios. Linear regression analyses were employed to disclose any potential correlation between mitochondrial dysfunction and aging. RESULTS: We found a progressive, significant increase of heart membrane lipid peroxidation with aging (P<0.05). Conversely, neither AEA nor REA decreased with age (P=n.s. for all complexes). Similarly to observations in other tissues, we found that stoichiometry of the MRC enzymes is maintained within a narrow range in human hearts. When the effects of aging on MRC ratios were explored, we failed again in demonstrating any subtle disarray. CONCLUSION: MRC enzymes remain preserved in heart with aging, and thus they cannot be considered the main cause of the increased oxidative damage associated with aging.


Asunto(s)
Envejecimiento/metabolismo , Peroxidación de Lípido , Mitocondrias Cardíacas/enzimología , Miocardio/metabolismo , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Análisis de Varianza , Membrana Celular/metabolismo , Niño , Transporte de Electrón , Femenino , Glutatión Peroxidasa/metabolismo , Humanos , Modelos Lineales , Masculino , Persona de Mediana Edad , Complejos Multienzimáticos/metabolismo , Prohibitinas , Espectrofotometría , Superóxido Dismutasa/análisis
19.
Alcohol Clin Exp Res ; 24(6): 859-64, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10888075

RESUMEN

BACKGROUND: Harmful effects of chronic ethanol intake on liver mitochondria have been clearly demonstrated; however, mitochondria from skeletal muscle are preserved, and the effect of ethanol on heart mitochondria remains controversial. We assessed individual enzyme activity of mitochondrial respiratory chain (MRC) complexes and membrane oxidative damage of heart mitochondria in active ethanol drinkers before the development of dilated cardiomyopathy. PATIENTS AND METHODS: Heart samples were obtained from otherwise healthy organ donor individuals with a sudden death of traumatic or neurological cause in whom hearts could not be used because of absence of matched receptors or size inadequacy. Detailed history of alcohol intake was achieved from the relatives. Citrate synthase activity was spectrophotometrically assayed, as well as absolute (nmol x min(-1) x mg protein(-1)) and relative (corrected by citrate synthase) activities of complex I, II, III, and IV of the MRC. Oxidative damage of myocardium membranes was assessed measuring the degree of lipid peroxidation by fluorescence using cis-parinaric acid as probe. RESULTS: We included 10 ethanol drinkers (age 53 +/- 13 years, 100% males, mean lifetime intake of 15.6 +/- 7.9 kg ethanol kg body weight(-1)) and 12 controls (age 60 +/- 10 years, 75% males). Mitochondrial content did not differ between the two groups. Absolute enzyme activities for ethanol drinkers and controls were, respectively, 145 +/- 75 and 130 +/- 50 for complex I (p = NS); 399 +/- 193 and 376 +/- 100 for complex II (p = NS); 719 +/- 288 and 714 +/- 308 for complex III (p = NS); and 475 +/- 139 and 570 +/- 160 for complex IV (p = NS). After correcting such activities by citrate synthase activity, we failed again to demonstrate differences between ethanol drinkers and controls. Lipid peroxidation of myocardium membranes was similar in both groups. CONCLUSIONS: Chronic ethanol drinkers without cardiomyopathy exhibit normal MRC activity in the heart and do not show increased oxidative damage in myocardial membranes.


Asunto(s)
Consumo de Bebidas Alcohólicas/metabolismo , Complejo III de Transporte de Electrones/metabolismo , Transporte de Electrón/fisiología , Mitocondrias Cardíacas/metabolismo , Adulto , Anciano , Análisis de Varianza , Cardiomiopatías , Depresores del Sistema Nervioso Central/farmacología , Transporte de Electrón/efectos de los fármacos , Complejo III de Transporte de Electrones/efectos de los fármacos , Etanol/farmacología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mitocondrias Cardíacas/efectos de los fármacos
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