Publications (50)266.04 Total impact
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Article: Study of oxidative, enzymatic mitochondrial respiratory chain function and apoptosis in perinatally HIV-infected pediatric patients.
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ABSTRACT: Abstract Mitochondrial toxicity in perinatally human immunodeficiency virus (HIV)-infected pediatric patients has been scarcely investigated. Limited data are available about HIV or antiretroviral (ARV)-mediated mitochondrial damage in this population group, specifically, regarding oxygen consumption and apoptosis approach. We aimed to elucidate whether a given mitochondrial DNA depletion is reflected at downstream levels, to gain insight on the pathology of HIV and highly active antiretroviral therapy (HAART) in perinatally HIV-infected pediatric patients. We studied 10 healthy control participants and 20 perinatally HIV-infected pediatric patients (10 under ARV treatment and 10 off treatment). We determined mitochondrial mass, subunits II and IV of complex IV, global and specific mitochondrial enzymatic and oxidative activities, and apoptosis from peripheral blood mononuclear cells. Global oxygen consumption was significantly compromised in HIV-infected untreated patients, compared to the control group (0.76 ± 0.01 versus 1.59 ± 0.15; P = 0.014). Apoptosis showed a trend to increase in untreated patients as well. The overall complex (C) CI-III-IV activity of the mitochondrial respiratory chain (MRC) was significantly decreased in HIV-infected treated patients with respect to the control group (1.52 ± 0.38 versus 6.38 ± 1.53; P = 0.02). No statistically significant differences were found between untreated and HAART-treated patients. These findings suggest the pathogenic role of both HIV and HAART in mitochondrial dysfunction in vertical infection. The abnormalities in mitochondrial genome may be downstream reflected through a global alteration of the MRC. Mitochondrial impairment associated with HIV and HAART was generalized, rather than localized, in this series of perinatally HIV-infected patients.Drug and Chemical Toxicology 03/2013; · 1.08 Impact Factor -
Article: Mitochondrial evolution in HIV-infected children receiving first- or second-generation nucleoside analogues.
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ABSTRACT: Highly active antiretroviral therapy (HAART) and HIV-related mitochondrial toxicity lead to several adverse effects and have become a major issue, especially in children. The main goal in the treatment of HIV-infected children is to maximize cost-effectiveness while minimizing toxicity. We aimed to study the evolution of mitochondrial parameters over time in children receiving different types antiretroviral regimens. We followed-up 28 HIV-infected children receiving HAART including either first-generation nucleoside reverse transcriptase inhibitors (1gNRTIs; didanosine, zidovudine, or stavudine; n = 15) or second-generation NRTIs (2gNRTIs; the remaining drugs; n = 13) for a period of 2 years for their immunovirological and mitochondrial status, and compared these subjects with a group of untreated HIV-infected patients (n = 10) and uninfected controls (n = 27). We measured T-lymphocyte CD4+ content (flow cytometry), viral load (real-time polymerase chain reaction), and lactate levels (spectrophotometry); we assessed mtDNA content (real-time polymerase chain reaction), mitochondrial protein levels (Western blot), oxidative stress, mitochondrial mass, and electron transport chain function (spectrophotometry) in peripheral blood mononuclear cells. At the second time point, lactate levels were significantly higher in children on 1gNRTIs compared with those receiving 2gNRTIs (1.28 ± 0.08 vs. 1.00 ± 0.07 mmol/L, respectively; P = 0.022). MtDNA content was similar among all HIV-infected groups and significantly lower than in healthy controls at baseline. Oxidative stress tended to increase over time in all the groups, with no differences among them. However, a significant decrease in cytochrome c oxidase activity was found over time in HIV-infected patients; this decline was greater in the 1gNRTIs group. HIV infection and the use of 1gNRTIs caused greater mitochondrial damage than 2gNRTIs over time. The higher lactate levels and the significant decrease observed in cytochrome c oxidase activity argue against the use of 1gNRTIs in HIV-infected children when an alternative is available, in accordance with international recommendations.JAIDS Journal of Acquired Immune Deficiency Syndromes 02/2012; 60(2):111-6. · 4.43 Impact Factor -
Article: The effects of sepsis on mitochondria.
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ABSTRACT: Sepsis is associated with mitochondrial dysfunction and impaired oxygen consumption, which may condition clinical outcome independent of tissue oxygenation. However, mitochondrial role in sepsis severity remains unknown. We aimed to characterize mitochondrial function in sepsis, establish its origin and cellular consequences, and determine its correlation with clinical symptoms and outcome. Different markers of mitochondrial activity, nitrosative and oxidative stress, apoptosis, and inflammation were measured in peripheral blood mononuclear cells (PBMCs) and plasma of 19 septic patients and 20 controls. Plasma capacity to induce mitochondrial dysfunction was assessed in muscle mitochondria from 5 healthy individuals incubated with plasma of septic patients or controls. Despite unaltered mitochondrial mass and protein synthesis, enzymatic mitochondrial complexes I, III, and IV and oxygen consumption were significantly inhibited in sepsis. Septic plasma tended to reduce oxygen consumption of healthy mitochondria and showed significantly increased amounts of extracellular mitochondrial DNA and inflammatory cytokines, especially in patients presenting adverse outcome. Active nuclear factor kappa-light-chain enhancer of activated B cells (NFKB) was also significantly increased, together with nitric oxide, oxidative stress and apoptosis. Additionally, sepsis severity significantly correlated with complex I inhibition, NFKB activation and intercellular adhesion molecule expression. A plasmatic factor such as nitric oxide, increased in inflammation and able to induce mitochondrial dysfunction, oxidative stress and apoptosis, may be responsible for cell damage in sepsis. Together with bacterial infection, leakage of mitochondrial DNA from damaged cells into circulation could contribute to systemic inflammatory response syndrome. Mitochondrial dysfunction and inflammation correlate with sepsis severity and outcome, becoming targets for supporting therapies.The Journal of Infectious Diseases 12/2011; 205(3):392-400. · 6.41 Impact Factor -
Article: Perinatal outcomes, mitochondrial toxicity and apoptosis in HIV-treated pregnant women and in-utero-exposed newborn.
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ABSTRACT: Highly active antiretroviral therapy (HAART) has decreased the risk of HIV mother-to-child transmission. However, HIV and HAART have been associated with adverse perinatal outcome. HAART has been associated with mitochondrial dysfunction in nonpregnant adults, and HIV, additionally, to apoptosis. We determined whether mitochondrial toxicity and apoptosis are present in HIV-pregnant women and their newborns and could be the basis of adverse pregnancy outcome. Single-site, cross-sectional, controlled observational study without intervention. We studied mitochondrial and apoptotic parameters in mononuclear cells from maternal peripheral blood and infant cord blood at delivery in 27 HIV-infected and treated pregnant women, and 35 uninfected controls and their infants, to correlate clinical outcome with experimental findings: mitochondrial number (CS), mtDNA content (ND2/18SrRNA), mitochondrial protein synthesis (COX-II/V-DAC), mitochondrial function (enzymatic activities) and apoptotic rate (caspase-3/β-actin). Global adverse perinatal outcome, preterm births and small newborn for gestational age were significantly increased in HIV pregnancies [odds ratio (OR) 7.33, 5.77 and 9.71]. Mitochondrial number was unaltered. The remaining mitochondrial parameters were reduced in HIV mothers and their newborn; especially newborn mtDNA levels, maternal and fetal mitochondrial protein synthesis and maternal glycerol-3-phosphate + complex III function (38.6, 25.8, 13.6 and 31.2% reduced, respectively, P < 0.05). All materno-fetal mitochondrial parameters significantly correlated, except mtDNA content. Apoptosis was exclusively increased in infected pregnant women, but not in their newborn. However, adverse perinatal outcome did not correlate mitochondrial or apoptotic findings. Transplacental HAART toxicity may cause subclinical mitochondrial damage in HIV-pregnant women and their newborn. Trends to increased maternal apoptosis may be due to maternal-restricted HIV infection. However, we could not demonstrate mitochondrial or apoptotic implication in adverse perinatal outcome.AIDS (London, England) 12/2011; 26(4):419-28. · 4.91 Impact Factor -
Article: Mitochondrial impact of human immunodeficiency virus and antiretrovirals on infected pediatric patients with or without lipodystrophy.
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ABSTRACT: We determined the mitochondrial status of a group of HIV-infected children, some with body fat abnormalities (BFA). We included 24 controls, 16 HIV-infected untreated, 26 HIV-infected treated, 6 BFA-untreated, and 21 BFA-treated patients. Genetic, translational, and functional mitochondrial values were measured. As compared with controls, mitochondrial DNA depletion and a reduction in functionality were found in BFA groups.The Pediatric Infectious Disease Journal 06/2011; 30(11):992-5. · 3.58 Impact Factor -
Article: Type 1 autoimmune hepatitis in a patient with microscopic polyangiitis: challenges in diagnosis and treatment.
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ABSTRACT: Autoimmune diseases/autoantibodies tend sometimes to cumulate in the same individual, probably as a consequence of defects in immune regulation with breakdown of self-tolerance. Autoimmune hepatitis and microscopic polyangiitis have been occasionally reported with other autoimmune diseases, but the particular association of these both disorders has not been previously reported in the English and Spanish medical literature. A 72 year-old woman presented with symptoms suggesting giant cell arteritis and polymyalgia rheumatica. A temporal artery biopsy disclosed a spared temporal artery, with vasculitis involving surrounding small vessels. Anti-neutrophil cytoplasmic antibodies were positive, with myeloperoxidase specificity. Increased liver enzymes led to a wider autoantibody determination. Anti-nuclear antibodies and anti-smooth muscle cell antibodies with anti-f-actin specificity were also positive. A liver biopsy showed changes consistent with autoimmune hepatitis. Clues for the diagnosis of vasculitis and AIH in the context of this patient, challenges in its classification among systemic vasculitides, and difficulties in the choice of a suitable therapeutic management for this particular association are discussed.Medicina Clínica 02/2011; 136(8):345-8. · 1.38 Impact Factor -
Article: Mitochondrial damage in adipose tissue of untreated HIV-infected patients.
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ABSTRACT: antiretrovirals, especially thymidine-analogue nucleoside reverse transcriptase inhibitors (tNRTIs), may cause the mitochondrial damage in adipose tissue that has been associated with lipodystrophy development. HIV itself may damage blood cell mitochondria. However, the viral capacity to induce adipose tissue mitochondrial lesion is still a matter of doubt. We aimed to assess whether untreated HIV infection was associated with adipose tissue mitochondrial abnormalities. : Single-site, cross-sectional, controlled observational and exploratory study without intervention. we included 24 uninfected controls and 18 HIV-infected patients with undetectable viral load and no clinical signs of lipodystrophy stratified as antiretroviral naive (n = 11) or at least 6-month antiviral-treated with a double NRTI combination, including lamivudine plus one tNRTI (n = 7). Subcutaneous adipose tissue was homogenated to determine mtDNA content by rtPCR and mitochondrial function per mitochondria through the spectrophotometric measurement of cytochrome c oxidase activity normalized by citrate synthase amount (COX/citrate synthase). Differences in mitochondrial parameters among groups were sought to determine the contribution of HIV and antiretrovirals to mitochondrial alterations. compared with uninfected controls (arbitrarily assigned 100%), naive individuals presented a marked decrease in adipose tissue mtDNA content and COX/citrate synthase function (62 and 75% remaining content/activity, P < 0.001 and P < 0.05). Antiretrovirals did not increase this impairment (69 and 70% remaining content/activity, P < 0.05 compared to controls and P = not significant compared to naives). Additionally, molecular and functional mitochondrial parameters were positively correlated (P < 0.05). in nonlipodystrophic HIV-infected naive patients, viral infection is associated with adipose tissue mtDNA decrease and mitochondrial dysfunction independently of antiretroviral treatment.AIDS (London, England) 01/2011; 25(2):165-70. · 4.91 Impact Factor -
Article: Mitochondrial assessment in asymptomatic HIV-infected paediatric patients on HAART.
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ABSTRACT: HAART can cause mitochondrial DNA (mtDNA) depletion, which may lead to mitochondrial dysfunction. We aimed to determine whether mtDNA and mitochondrial function abnormalities are present in peripheral blood mononuclear cells from asymptomatic HIV-infected children. A cross-sectional study in peripheral blood mononuclear cells was performed in 47 asymptomatic (free from any HIV- or AIDS-related active condition or HAART-related toxicity), HIV-infected, HAART-treated children and adolescents and 27 uninfected healthy paediatric patients. We measured mtDNA and mitochondrial RNA (mtRNA) content by quantitative real-time PCR. Mitochondrial respiratory chain enzymatic activity of complex-IV (CIV) and mitochondrial mass (estimated by citrate synthase) were measured spectrophotometrically, and CIV protein subunit content was measured with western blot analysis. A reduction in mtDNA levels was observed in HIV-infected children compared with controls (mean ± sem 4.47 ± 0.31 and 5.82 ± 0.48, respectively; 23% depletion; P=0.018), whereas similar levels of mtRNA, CIV protein subunit content and enzymatic activity were found in the two groups. These findings remained unaltered after considering mitochondrial abundance. Among HIV-infected children, mtDNA levels did not correlate with viral load, CD4(+) T-cell counts or lactataemia at the time of assessment. No differences were observed when current or past use of individual antiretroviral drugs or HAART regimens were taken into account. Depletion in mtDNA from asymptomatic HIV-infected children did not lead to differences in mtRNA levels or mitochondrially-encoded CIV proteins, nor to CIV dysfunction. This may be explained by homeostatic-compensatory mechanisms at the transcription level or by the mild depletion we observed.Antiviral therapy 01/2011; 16(5):719-24. · 3.16 Impact Factor -
Article: Type 1 autoimmune hepatitis in a patient with microscopic polyangiitis: challenges in diagnosis and treatment
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ABSTRACT: Background and objective: Autoimmune diseases/autoantibodies tend sometimes to cumulate in the same individual, probably as a consequence of defects in immune regulation with breakdown of self-tolerance. Autoimmune hepatitis and microscopic polyangiitis have been occasionally reported with other autoimmune diseases, but the particular association of these both disorders has not been previously reported in the English and Spanish medical literature. Case report: A 72 year-old woman presented with symptoms suggesting giant cell arteritis and polymyalgia rheumatica. Results: A temporal artery biopsy disclosed a spared temporal artery, with vasculitis involving surrounding small vessels. Anti-neutrophil cytoplasmic antibodies were positive, with myeloperoxidase specificity. Increased liver enzymes led to a wider autoantibody determination. Anti-nuclear antibodies and anti-smooth muscle cell antibodies with anti-f-actin specificity were also positive. A liver biopsy showed changes consistent with autoimmune hepatitis. Conclusions: Clues for the diagnosis of vasculitis and AIH in the context of this patient, challenges in its classification among systemic vasculitides, and difficulties in the choice of a suitable therapeutic management for this particular association are discussed. Fundamento y objetivo: Las enfermedades autoinmunes/autoanticuerpos en ocasiones tienden a presentarse en un mismo individuo, probablemente por defectos en la regulació n inmune con pé rdida de la autotolerancia. La hepatitis autoinmune y la poliangiítis microscó pica se han descrito ocasionalmente asociadas a otras enfermedades autoinmunes, si bien la asociació n particular de ambas entidades no se ha descrito previamente en literatura mé dica inglesa o castellana. Observación clı´nica: Mujer de 72 añ os que ingresó con síntomas sugestivos de arteritis de cé lulas gigantes y polimialgia reumá tica. Resultados: Una biopsia de arteria temporal mostró una arteria indemne con presencia de vasculitis en vasos de pequeñ o tamañ o a su alrededor. Una biopsia muscular confirmó la existencia de una vasculitis sisté mica de pequeñ o vaso. Los anticuerpos anticitoplasma de neutró filo fueron positivos, con especificidad antimieloperoxidasa. Dada la presencia de elevació n de las enzimas hepá ticas y anticuerpos antinucleares con especificidad anti-actina, se realizó una biopsia hepá tica que mostró cambios compatibles con una hepatitis autoinmune.Med Clin (Barc). 01/2011; 136:345-348. -
Article: Evolution of mitochondrial DNA content after planned interruption of HAART in HIV-infected pediatric patients.
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ABSTRACT: HAART-related long-term toxicities, many of them ascribed to mitochondrial (mt) toxicity of the nucleoside analogues, are being increasingly reported in HIV-infected children. HIV infection can also cause mt damage. Case series include 13 vertically HIV-infected pediatric patients (9 girls, median age 10.5 years) with optimal long-term response to a first-line HAART regimen who underwent planned treatment interruption (PTI). MtDNA content from peripheral blood mononuclear cells was assessed by means of a real-time PCR technique at PTI and 12 months later and expressed as an mtDNA/nuclear DNA ratio, together with lactate levels. At PTI, patients had remained a median time of 4.7 years on HAART and 4.3 years with complete suppression of viral replication. The main reason leading to PTI was treatment fatigue. One month after PTI, HIV plasmatic viral load had increased to 4.8 log copies/ml and stabilized thereafter. During the 12-month study period, all children remained free from any HIV-related clinical event. A progressive and significant decrease in median CD4 cell counts and percentages was observed 12 months after PTI. One year after PTI, the median mtDNA/nuclear DNA ratios had increased from 0.76 to 1.08 (p = 0.002) and lactate levels had decreased (from 1.12 to 0.73 mmol/liter; p = 0.019). Changes in mtDNA did not correlate with changes in lactate levels. No relationship was found between the evolution in mt toxicity markers and the rest of the clinical, immunological, and virological variables. In this series, PTI led to a partial restoration of mtDNA levels and a significant decrease in lactate values.AIDS research and human retroviruses 09/2010; 26(9):1015-8. · 2.18 Impact Factor -
Article: [Rare diseases and the internal medicine specialist].
Medicina Clínica 03/2010; 134(12):540-1. · 1.38 Impact Factor -
Article: Genetic and functional mitochondrial assessment of HIV-infected patients developing HAART-related hyperlactatemia.
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ABSTRACT: Mitochondrial damage of HIV and antiretrovirals, especially nucleoside-analogue interference on mitochondrial DNA (mtDNA) replication, is reported to underlay highly active antiretroviral therapy (HAART)-related hyperlactatemia, but scarce approaches have been performed to correlate clinical manifestations and mitochondrial abnormalities. We obtained lymphocytes and monocytes of 26 HIV-infected and treated patients who developed hyperlactatemia and after recovery, 28 nonhyperlactatemic HIV subjects on HAART, 31 naive individuals, and 20 uninfected controls. Mitochondrial replication and transcription analysis were performed by quantitative real-time PCR, mitochondrial translation quantification by western blot and mitochondrial enzymatic activities by spectrophotometry. Mitochondrial parameters decreased during hyperlactatemia and improved at recovery. Mitochondrial replication and transcription species were reduced (P = 0.16 and P = 0.71), but the most significant decay was observed on mitochondrial protein content (P < 0.05) and mitochondrial complexes III and IV activities (P < 0.01 and P < 0.001). During hyperlactatemia lactate level correlated complexes III and IV function (P < 0.05). After recovery mitochondrial parameters achieved values of nonhyperlactatemic HIV individuals, which were lower than ranges of naive subjects and uninfected controls. HIV and HAART-related hyperlactatemia is associated with a general mitochondrial impairment which reverts after recovery. Mitochondrial biochemistry show a better correlation with lactate levels than mitochondrial genetics suggesting that mitochondrial function could be a better marker of hyperlactatemia development than mtDNA content.JAIDS Journal of Acquired Immune Deficiency Syndromes 09/2009; 52(4):443-51. · 4.43 Impact Factor -
Article: [Reply.]
Medicina Clínica 05/2009; · 1.38 Impact Factor -
Article: Mitochondrial Cytochrome c Oxidase Inhibition during Acute Carbon Monoxide Poisoning
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ABSTRACT: Clinical symptoms of acute carbon monoxide (CO) poisoning are mainly related to the capability of haemoglobin to bind CO. However, the persistence of some clinical alterations after carboxyhaemoglobin normalization suggests that other heme containing proteins, like cytochrome c oxidase, could play a role in its pathogenesis. We studied mitochondrial enzyme activities of lymphocytes from three patients suffering from acute CO poisoning. HbCO levels were 11.6%, 19.6% and 22.3% in the acute phase, 2.3%, 2.4% and 1.5% on day 3 after admission, and 1.2%, 3.3% and 1.1% on day 12. Complex II, III and glycerol–3–phosphate dehydrogenase activities remained normal along the study, while cytochrome coxidase (complex IV) activity showed a 76% inhibition compared to controls during acute poisoning (P < 0.01) and 48% at day 3 (P < 0.05). The activity was normal already on day 12 after the complete disappearance of symptomatology. Our results suggest that mitochondrial cytochrome c oxidase is also a target site in human acute CO poisoning, and its extended and generalized inhibition could explain the persistence of different symptoms after the normalization of HbCO levels.Pharmacology & Toxicology 03/2009; 82(4):199 - 202. -
Article: [Postgraduate medical training in Spain (MIR): a proposal for the adaptation to the sanitary model requirements].
Medicina Clínica 01/2009; 131(20):777-82. · 1.38 Impact Factor -
Article: Mitochondrial DNA depletion in oocytes of HIV-infected antiretroviral-treated infertile women.
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ABSTRACT: HIV-infected women under highly active antiretroviral therapy (HAART) undergoing in vitro fertilization (IVF) have a lower pregnancy rate than noninfected controls, which depends on oocyte-related factors. We hypothesized that mitochondrial toxicity caused by antiretrovirals could be the underlying mechanism of such disturbance. We have studied 16 and 19 frozen-thawed oocytes obtained after oocyte retrieval IVF cycles from 8 and 14 infertile HIV-infected and uninfected women, respectively, matched by age. At inclusion, HIV-positive women had been infected for >13 years and had received HAART for >9 years, including at least one nucleoside reverse transcriptase inhibitor. All of them had undetectable HIV viral load and a good immunological status. Mitochondrial DNA (mtDNA) content was determined by quantitative real-time PCR in each individual oocyte. HIV-infected infertile women on HAART showed significant oocyte mtDNA depletion when compared with uninfected controls (32% mtDNA decrease, P<0.05). This oocyte mtDNA depletion was even greater on those HIV-infected women who failed to become pregnant when compared with controls (39% mtDNA decrease, P=0.03). No significant correlation was found between mtDNA oocyte content and cumulative doses of antiretrovirals or the immunological status of HIV patients. Oocytes from infertile HIV-infected HAART-treated women show decreased mtDNA content, and this could explain their poor reproductive outcome.Antiviral therapy 01/2008; 13(6):833-8. · 3.16 Impact Factor -
Article: Partial immunological and mitochondrial recovery after reducing didanosine doses in patients on didanosine and tenofovir-based regimens.
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ABSTRACT: Tenofovir disoproxil fumarate (TDF) has a safe toxicity profile; however, administration together with didanosine (ddl) increases ddl levels causing mitochondrial damage and CD4+ T-cell decline. We assessed whether a simple reduction of the ddl dose in patients receiving ddl (400 mg/day) and TDF could revert this side effect. Immunological and mitochondrial changes were analysed in 20 patients at baseline, after 14 months of receiving ddl (400 mg/day), TDF (300 mg/day) and nevirapine (NVP; 400 mg/day) and 14 months after a ddl dose reduction to 250 mg/day. Immunological analyses measured CD4+ and CD8+ T-cell counts and mitochondrial studies in peripheral blood mononuclear cells assessed mitochondrial DNA content by quantitative real-time PCR, cytochrome c oxidase (COX) activity by spectrophotometry and mitochondrial protein synthesis (COX-II versus beta-actin or COX-IV expression) by western blot. Treatment with TDF, ddl (400 mg/day) and NVP for 14 months produced significant decreases in mitochondrial parameters and CD4+ T-cell counts. The reduction in ddl dose resulted in mitochondrial DNA recovery; however, the remaining mitochondrial parameters remained significantly decreased. Levels of CD4+ T-cells were partially restored in 35% of patients. Subjects presenting a significant reduction in CD4+ T-cells during the high ddl dose period showed greater mitochondrial impairment in this stage and better mitochondrial and immunological recovery after drug reduction. Administration of high ddl doses together with TDF was associated with mitochondrial damage, which may explain the observed CD4+ T-cell decay. A reduction of the ddl dose led to mitochondrial DNA recovery, but was not sufficient to recover baseline CD4+ T-cell counts. Other mitochondrial toxicity in addition to DNA gamma-polymerase inhibition could be responsible for CD4+ T-cell toxicity.Antiviral therapy 01/2008; 13(2):231-40. · 3.16 Impact Factor -
Article: Neuroleptic treatment effect on mitochondrial electron transport chain: peripheral blood mononuclear cells analysis in psychotic patients.
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ABSTRACT: A limitation in the use of classic neuroleptic drugs is the eventual appearance of extrapyramidal symptoms. Some studies, mainly based on experimental situations, have related these symptoms with a defect in the mitochondrial electron transport chain (ETC), especially with complex I (CI). One of the advantages of the "atypical" neuroleptics is a lower incidence of movement disorders. We studied peripheral blood mononuclear cells from naive schizophrenic patients (n = 25) and patients under chronic treatment with 1 "typical" neuroleptic (haloperidol, n = 15) or 1 "atypical" neuroleptic (risperidone, n = 23; or clozapine, n = 21). Patients were on standard clinical situation, on treatment for at least 28 months, and did not present signs or symptoms of extrapyramidal dysfunction. Absolute enzyme activities of ETC complexes I to IV were spectrophotometrically quantified, and oxygen consumption with substrates of different complexes was measured polarographically. As an indirect measure of oxidative damage, we quantified membrane lipid peroxidation through the loss of cis-parinaric acid fluorescence. We found differences among groups when comparing the activity of CI, which was decreased in patients receiving neuroleptics, either assessed enzymatically or through oxygen consumption. This effect was lower for atypical neuroleptics than for haloperidol. Haloperidol was also associated with a significant increase of peripheral blood mononuclear cell membrane peroxidation. We conclude that antipsychotics given at clinical standard doses, either typical or atypical, inhibit CI of the ETC. It remains to be established if this finding in a nontarget tissue for antipsychotics may account for the lower incidence of movement disorders observed in patients on atypical agents.Journal of Clinical Psychopharmacology 07/2007; 27(3):284-8. · 4.10 Impact Factor -
Article: Reversible inhibition of mitochondrial protein synthesis during linezolid-related hyperlactatemia.
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ABSTRACT: The objective of the present study was to determine the mitochondrial toxicity mechanisms of linezolid-related hyperlactatemia. Five patients on a long-term schedule of linezolid treatment were studied during the acute phase of hyperlactatemia and after clinical recovery and lactate normalization following linezolid withdrawal. Mitochondrial studies were performed with peripheral blood mononuclear cells and consisted of measurement of mitochondrial mass, mitochondrial protein synthesis homeostasis (cytochrome c oxidase [COX] activity, COX-II subunit expression, COX-II mRNA abundance, and mitochondrial DNA [mtDNA] content), and overall mitochondrial function (mitochondrial membrane potential and intact-cell oxidative capacity). During linezolid-induced hyperlactatemia, we found extremely reduced protein expression (16% of the remaining content compared to control values [100%], P < 0.001) for the mitochondrially coded, transcribed, and translated COX-II subunit. Accordingly, COX activity was also found to be decreased (51% of the remaining activity, P < 0.05). These reductions were observed despite the numbers of COX-II mitochondrial RNA transcripts being abnormally increased (297%, P = 0.10 [not significant]) and the mitochondrial DNA content remaining stable. These abnormalities persisted even after the correction for mitochondrial mass, which was mildly decreased during the hyperlactatemic phase. Most of the mitochondrial abnormalities returned to control ranges after linezolid withdrawal, lactate normalization, and clinical recovery. Linezolid inhibits mitochondrial protein synthesis, leading to decreased mitochondrial enzymatic activity, which causes linezolid-related hyperlactatemia, which resolves upon discontinuation of linezolid treatment.Antimicrobial Agents and Chemotherapy 04/2007; 51(3):962-7. · 4.84 Impact Factor -
Article: Statistical reviewers improve reporting in biomedical articles: a randomized trial.
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ABSTRACT: Although peer review is widely considered to be the most credible way of selecting manuscripts and improving the quality of accepted papers in scientific journals, there is little evidence to support its use. Our aim was to estimate the effects on manuscript quality of either adding a statistical peer reviewer or suggesting the use of checklists such as CONSORT or STARD to clinical reviewers or both. Interventions were defined as 1) the addition of a statistical reviewer to the clinical peer review process, and 2) suggesting reporting guidelines to reviewers; with "no statistical expert" and "no checklist" as controls. The two interventions were crossed in a 2x2 balanced factorial design including original research articles consecutively selected, between May 2004 and March 2005, by the Medicina Clinica (Barc) editorial committee. We randomized manuscripts to minimize differences in terms of baseline quality and type of study (intervention, longitudinal, cross-sectional, others). Sample-size calculations indicated that 100 papers provide an 80% power to test a 55% standardized difference. We specified the main outcome as the increment in quality of papers as measured on the Goodman Scale. Two blinded evaluators rated the quality of manuscripts at initial submission and final post peer review version. Of the 327 manuscripts submitted to the journal, 131 were accepted for further review, and 129 were randomized. Of those, 14 that were lost to follow-up showed no differences in initial quality to the followed-up papers. Hence, 115 were included in the main analysis, with 16 rejected for publication after peer review. 21 (18.3%) of the 115 included papers were interventions, 46 (40.0%) were longitudinal designs, 28 (24.3%) cross-sectional and 20 (17.4%) others. The 16 (13.9%) rejected papers had a significantly lower initial score on the overall Goodman scale than accepted papers (difference 15.0, 95% CI: 4.6-24.4). The effect of suggesting a guideline to the reviewers had no effect on change in overall quality as measured by the Goodman scale (0.9, 95% CI: -0.3-+2.1). The estimated effect of adding a statistical reviewer was 5.5 (95% CI: 4.3-6.7), showing a significant improvement in quality. This prospective randomized study shows the positive effect of adding a statistical reviewer to the field-expert peers in improving manuscript quality. We did not find a statistically significant positive effect by suggesting reviewers use reporting guidelines.PLoS ONE 01/2007; 2(3):e332. · 4.09 Impact Factor
Top co-authors
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Institutions
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2004–2013
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Hospital Clínic de Barcelona
Barcelona, Catalonia, Spain
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2010
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Hospital Sant Joan de Déu
Barcelona, Catalonia, Spain
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1998–2009
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University of Barcelona
- Departament de Medicina
Barcelona, Catalonia, Spain
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