RESUMEN
OBJECTIVES: To evaluate the diagnostic role of cerebrospinal fluid (CSF) ferritin and albumin index (AI = CSF albumin/serum albumin × 1000) in differentiating acute bacterial meningitis (ABM) from acute viral meningitis (AVM) in children. METHODS: The study included 42 cases each of ABM and AVM in pediatric age group. Receiver operating characteristic (ROC) analysis was carried out for CSF ferritin and AI. Binary logistic regression was also done. RESULTS: CSF ferritin and AI were found significantly higher in ABM compared to AVM. Model obtained using AI and CSF ferritin along with conventional criteria is better than existing models.
Asunto(s)
Albúminas/análisis , Ferritinas/líquido cefalorraquídeo , Meningitis Bacterianas/diagnóstico , Meningitis Viral/diagnóstico , Enfermedad Aguda , Albúminas/líquido cefalorraquídeo , Niño , Diagnóstico Diferencial , Femenino , Humanos , Modelos Logísticos , Masculino , Curva ROC , Albúmina Sérica/análisisRESUMEN
Collagen VI myopathies (Ullrich congenital muscular dystrophy (UCMD), Bethlem myopathy (BM), and myosclerosis myopathy) share a common pathogenesis, that is, mitochondrial dysfunction due to deregulation of the permeability transition pore (PTP). This effect was first identified in the Col6a1(-/-) mouse model and then in muscle cell cultures from UCMD and BM patients; the normalizing effect of cyclosporin A (CsA) confirmed the pathogenic role of PTP opening. In order to determine whether mitochondrial performance can be used as a criterion for inclusion in clinical trials and as an outcome measure of the patient response to therapy, it is mandatory to establish whether mitochondrial dysfunction is conserved in primary cell cultures from UCMD and BM patients. In this study we report evidence that mitochondrial dysfunction and the consequent increase of apoptotic rate can be detected not only, as previously reported, in muscle, but also in fibroblast cell cultures established from muscle biopsies of collagen VI-related myopathic patients. However, the mitochondrial phenotype is no longer maintained after nine passages in culture. These data demonstrate that the dire consequences of mitochondrial dysfunction are not limited to myogenic cells, and that this parameter can be used as a suitable diagnostic criterion, provided that the cell culture conditions are carefully established.
Asunto(s)
Ensayos Clínicos como Asunto/métodos , Colágeno Tipo VI/metabolismo , Mitocondrias/metabolismo , Mitocondrias/patología , Enfermedades Musculares/metabolismo , Enfermedades Musculares/patología , Adolescente , Adulto , Apoptosis/fisiología , Células Cultivadas , Niño , Contractura/metabolismo , Contractura/patología , Fibroblastos/metabolismo , Fibroblastos/patología , Humanos , Persona de Mediana Edad , Músculo Esquelético/metabolismo , Músculo Esquelético/fisiopatología , Distrofias Musculares/congénito , Distrofias Musculares/metabolismo , Distrofias Musculares/patología , Evaluación de Resultado en la Atención de Salud , Selección de Paciente , Fenotipo , Cultivo Primario de Células , Esclerosis/metabolismo , Esclerosis/patologíaRESUMEN
BACKGROUND AND PURPOSE: We have investigated the therapeutic effects of the selective cyclophilin inhibitor D-MeAla(3)-EtVal(4)-cyclosporin (Debio 025) in myopathic Col6a1(-/-) mice, a model of muscular dystrophies due to defects of collagen VI. EXPERIMENTAL APPROACH: We studied calcineurin activity based on NFAT translocation; T cell activation based on expression of CD69 and CD25; propensity to open the permeability transition pore in mitochondria and skeletal muscle fibres based on the ability to retain Ca(2+) and on membrane potential, respectively; muscle ultrastructure by electronmicroscopy; and apoptotic rates by terminal deoxynucleotidyl transferase-mediated dUTP nick end labelling assays in Col6a1(-/-) mice before after treatment with Debio 025. KEY RESULTS: Debio 025 did not inhibit calcineurin activity, yet it desensitizes the mitochondrial permeability transition pore in vivo. Treatment with Debio 025 prevented the mitochondrial dysfunction and normalized the apoptotic rates and ultrastructural lesions of myopathic Col6a1(-/-) mice. CONCLUSIONS AND IMPLICATIONS: Desensitization of the mitochondrial permeability transition pore can be achieved by selective inhibition of matrix cyclophilin D without inhibition of calcineurin, resulting in an effective therapy of Col6a1(-/-) myopathic mice. These findings provide an important proof of principle that collagen VI muscular dystrophies can be treated with Debio 025. They represent an essential step towards an effective therapy for Ullrich Congenital Muscular Dystrophy and Bethlem Myopathy, because Debio 025 does not expose patients to the potentially harmful effects of immunosuppression.
Asunto(s)
Colágeno Tipo VI/deficiencia , Ciclofilinas/antagonistas & inhibidores , Ciclosporina/farmacología , Mitocondrias/fisiología , Músculo Esquelético/ultraestructura , Enfermedades Musculares/patología , Animales , Apoptosis/efectos de los fármacos , Apoptosis/genética , Colágeno Tipo VI/genética , Ciclofilinas/fisiología , Ciclosporina/uso terapéutico , Relación Dosis-Respuesta a Droga , Humanos , Células Jurkat , Ratones , Ratones Noqueados , Mitocondrias/efectos de los fármacos , Mitocondrias/ultraestructura , Músculo Esquelético/efectos de los fármacos , Músculo Esquelético/patología , Enfermedades Musculares/tratamiento farmacológico , Enfermedades Musculares/genéticaRESUMEN
PURPOSE: This work investigates whether a synergy in cell death induction exists in combining atomic ions irradiation and addition of platinum salts. Such a synergy could be of interest in view of new cancer therapy protocol based on atomic ions--hadrontherapy--with the addition of radiosensitizing agents containing high-Z atoms. The experiment consists in irradiating by fast ions cultured cells previously exposed to dichloroterpyridine Platinum (PtTC) and analyzing cell survival by a colony-forming assay. MATERIALS AND METHODS: Chinese Hamster Ovary (CHO) cells were incubated for six hours in medium containing 350 microM PtTC, and then irradiated by fast ions C(6+) and He(2+), with Linear Energy Transfer (LET) within range 2-70 keV/microm. In some experiments, dimethyl sulfoxide (DMSO) was added to investigate the role of free radicals. The intracellular localization of platinum was determined by Nano Secondary Ion Mass Spectroscopy (Nano-SIMS). RESULTS: For all LET examined, cell death rate is largely enhanced when irradiating in presence of PtTC. At fixed irradiation dose, cell death rate increases with increasing LET, while the platinum relative effect is larger at low LET. CONCLUSION: This finding suggests that hadrontherapy or protontherapy therapeutic index could be improved by combining irradiation procedure with concomitant chemotherapy protocols using platinum salts.
Asunto(s)
Carbono , Iones Pesados , Helio , Transferencia Lineal de Energía , Compuestos Organoplatinos , Animales , Células CHO , Supervivencia Celular/fisiología , Supervivencia Celular/efectos de la radiación , Ensayo de Unidades Formadoras de Colonias , Cricetinae , Cricetulus , Dimetilsulfóxido/farmacología , Relación Dosis-Respuesta en la Radiación , Femenino , Radicales Libres/metabolismo , Compuestos Organoplatinos/química , Compuestos Organoplatinos/efectos de la radiación , Compuestos Organoplatinos/uso terapéutico , Dosis de Radiación , Tolerancia a Radiación , Espectrometría de Masa de Ion Secundario , Factores de TiempoRESUMEN
UVA (320-400 nm) radiation constitutes >90% of the environmentally relevant solar UV radiation, and it has been proposed to have a role in skin cancer and aging. Because of the popularity of UVA tanning beds and prolonged periods of sunbathing, the potential deleterious effect of UVA has emerged as a source of concern for public health. Although generally accepted, the impact of DNA damage on the cytotoxic, mutagenic, and carcinogenic effect of UVA radiation remains unclear. In the present study, we investigated the sensitivity of a panel of yeast mutants affected in the processing of DNA damage to the lethal and mutagenic effect of UVA radiation. The data show that none of the major DNA repair pathways, such as base excision repair, nucleotide excision repair, homologous recombination, and postreplication repair, efficiently protect yeast from the lethal action of UVA radiation. In contrast, the results show that the Ogg1 DNA glycosylase efficiently prevents UVA-induced mutagenesis, suggesting the formation of oxidized guanine residues. Furthermore, sequence analysis of UVA-induced canavanine-resistant mutations reveals a bias in favor of GC-->TA events when compared with spontaneous or H(2)O(2)-, UVC-, and gamma-ray- induced canavanine-resistant mutations in the WT strain. Taken together, our data point out a major role of oxidative DNA damage, mostly 7,8-dihydro-8-oxoguanine, in the genotoxicity of UVA radiation in the yeast Saccharomyces cerevisiae. Therefore, the capacity of skin cells to repair 7,8-dihydro-8-oxoguanine may be a key parameter in the mutagenic and carcinogenic effect of UVA radiation in humans.