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O Miró

Publications and source records attributed to O Miró.

At least 37 records · Page 2Linked to original sources

Aging is associated with increased lipid peroxidation in human hearts, but not with mitochondrial respiratory chain enzyme defects.

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.

Adolescent↗

[Prospective study of patients who leave the emergency department before being seen by the physician].

BACKGROUND: To define epidemiological characteristics, the main reasons, and outcome of patients who leave the emergency department (ED) without being seen by a physician. PATIENTS AND METHODS: We performed a prospective survey of patients who left the ED before medical visit over a period of 26 consecutive weeks. For every non-visited patient (NV), the next visited patient (V) was included as a control. Clinical and epidemiological data, reasons to leave ED and outcome were obtained from clinical records and personal telephone interview. RESULTS: Out of a total of 21,022 patients who were attended in the ED, 383 (1.8%) were NV. To be under 50-year-old, to come the ED alone, to be previously visited by a community physician, and to previous expect short waiting times for ED visit were associated with higher risk for being NV (p < 0.01, p < 0.01, p < 0.05 and p < 0.0001, respectively). The main reasons noted to leave the ED were: feeling better (35%), feeling too sick to wait longer (30%) and being too angry to wait (25%). Only 46% of the NV looked for medical care in the 72 following hours and 6.5% of them needing to be further to hospital. NV-patients considered as suffering a serious pathology at ED arrival, and those being visited by a community physician previously to go to ED were found to be at increased risk to be subsequently admitted (p = 0.01 and p = 0.001, respectively). CONCLUSIONS: Patients who leave ED department before being seen by a doctor are usually young, literate, have not previously visited their community physician, and consulted for minor complaints. The main reason to leave is their own impression of suffering a minor disease, and less than 50% visit another physician after their leaving, being the rate of hospital admission low. We should be particularly cautious with those patients referred by a community doctor and those identified as to have a seriously affected health status at their arrival at the hospital, since they are at increased risk to be admitted.

Age Factors↗

[Football, television and emergency services].

BACKGROUND: To know the influence of televised football on the use of emergency department (ED). PATIENTS AND METHODS: We assessed the number, demographic characteristics and acuity of patients attended during the broadcast of football matches played by FC Barcelona during Champions' League (n = 12), and they were compared with days without televised football (n = 12). RESULTS: Televised football was associated with a decrease in visits to ED (-18%; p = 0.002). Such a decrease was observed for all ED units, but only for traumatology unit reached statistical significance (-28%; p = 0.006). Decay of ED visits were mainly due to a decrease of low-acuity consults (-30%; p = 0.04). CONCLUSION: There is a significant decrease on ED use associated with televised football.

Adult↗

Mitochondrial function in heart muscle from patients with idiopathic dilated cardiomyopathy.

OBJECTIVE: To study the mitochondrial respiratory chain enzyme activities in patients with idiopathic dilated cardiomyopathy (IDC). METHODS: Mitochondrial respiratory chain enzyme activities were assessed spectrophotometrically in left ventricular tissue of 17 patients with IDC undergoing cardiac transplantation, as well as in two groups of controls: a group of six patients suffering from ischemic dilated cardiomyopathy (IC) also undergoing cardiac transplantation, and a group of 17 organ donors considered normal from a cardiac point of view. Cytochrome b gene from three IDC patients whose complex III activity was particularly low and from three controls was also sequenced. RESULTS: We found that complex III enzymatic activity was lower not only in IDC but also in IC patients when compared with normal controls. When analysing cytochrome b gene we only found neutral polymorphisms previously described. CONCLUSIONS: In view of such results, we believe that the decrease of respiratory chain complex III activity found in some cases of IDC is a secondary phenomenon, and not due to a primary mitochondrial disease.

Adult↗

Congenital and metabolic myopathies of childhood or adult onset.

OBJECTIVES: To investigate the clinical presentation, histological findings, and outcome of patients with congenital and metabolic myopathies (CM and MM) in whom the disease was diagnosed in childhood or adulthood. PATIENTS AND METHODS: We reviewed the diagnosis of all skeletal muscle biopsies performed by our group between 1984 and 1996 (13 years). All patients with CM and MM of childhood or adult onset were included in the study. Patients with mitochondrial myopathies were excluded because they are multisystemic disorders with a more distinct picture than that observed in other MM. We retrospectively reviewed the clinical history, with special emphasis on the clinical patterns of presentation, histological findings, and outcome. RESULTS: Among 1,865 biopsies, 28 (1.5%) fulfilled the diagnostic criteria for CM (seven nemaline myopathies, four multicore myopathies, three centronuclear myopathies) or MM (five adult-onset acid maltase deficiency, three myophosphorylase deficiency, three phosphofructokinase deficiency, two carnitine palmitoyl transferase deficiency, and one carnitine deficiency). In nearly half of the patients, mild stable weakness was the major complaint, whereas in one third muscular symptoms were intermittent and related to exercise. In a small number of cases, a persistently raised serum creatine kinase in an asymptomatic patient was the reason for muscle biopsy. Histological examination of skeletal muscle was highly indicative of a specific muscle disease in 26 of the 28 cases. After a mean follow-up of 7 years, the outcome has generally been good, and in most patients the myopathy did not worsen, most remaining ambulatory. CONCLUSION: CM and MM presenting in childhood or adulthood are infrequent; the symptoms are usually mild or moderate, and the prognosis generally is good.

Adolescent↗

Heart mitochondrial respiratory chain complexes are functionally unaffected in heavy ethanol drinkers without cardiomyopathy.

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.

Adult↗

Oxidative damage on lymphocyte membranes is increased in patients suffering from acute carbon monoxide poisoning.

Increased oxidative damage seems to be a relevant mechanism in the pathophysiology of patients with an acute carbon monoxide (CO) poisoning. We have investigated the degree of membrane oxidative damage through the assessment of lipid peroxidation in circulating lymphocytes from five patients acutely intoxicated by CO. Since mitochondria are a major source of reactive oxygen species and mitochondrial cytochrome c oxidase (COX) has been reported to be inhibited after acute CO poisoning, we have also assessed the lymphocyte COX activity and its relationship with the degree of lipid peroxidation. Data were compared with those from 32 non-smoker healthy controls comparable in terms of age, gender and physical activity. In intoxicated patients, we have found a significant increase of lipid peroxidation compared to control individuals (P < 0.05), as well as a marked COX inhibition (P < 0.001). Both parameters showed a positive, nearly significant correlation (r = 0.81, P = 0.09). We conclude that oxidative damage of lymphocyte membranes is increased after acute CO poisoning, and suggest that such increase could be partially mediated by mitochondrial COX inhibition caused by CO.

Acute Disease↗

[Study of mortality in a medical unit of emergency department: incidence, causes and consequences].

OBJECTIVES: To define the mortality pattern in a medical unit of emergency department (ED) and to know the satisfaction of relatives with ED provided care. PATIENTS AND METHODS: We computed the number of patients visited and dead from 1989 to 1996. From all patients dying during 1996, we recorded clinical and epidemiological data and we interviewed the patients' family to know their satisfaction with ED provided care. RESULTS: Whole mortality rate was 0.71 (0.15)% X (SD) with an annual increase of 10.4% (r = 0.78, p < 0.05). The clinical profile of patient dying at ED is an individual of advanced age, with a poor quality of life, and in whom the death was expected when arrived to ED. From the family interview, 61% of cases preferred that their relative was dying in the hospital, and 88% were satisfied with ED provided care. CONCLUSIONS: Although the annual mortality rate has progressively increased in ED, family satisfaction with the received care is good.

Age Factors↗

[Unscheduled revisits in medical emergency units at the hospital: incidence and related factors].

BACKGROUND: To known the revisit rate in an emergency department (ED), to define the clinical and epidemiological profile of revisited patients, and to identify influencing factors for revisits. PATIENTS AND METHODS: During one year period, we included all revisited patients returning to ED before 72 h of a previous discharge from medical unit of ED. As controls we included the next patient seen after every case being discharged. We compiled clinical and epidemiological data from both groups. For revisited patients, we identify the cause of the revisit, changes in diagnosis and/or treatment, diagnosis mistakes and final destination of the patient. RESULTS: We identified 406 revisits (revisit rate: 1.42%). Multivariate analysis disclosed, as positive predictive factors for revisit, and age over 60 years (p = 0.006), male sex (p = 0.02), visit performed at level 2 (severe diseases) (p = 0.02), initial assessment by junior resident (p = 0.01), number of complementary procedures higher than 2 (p = 0.01) and gastrointestinal disease as diagnosis after the first visit (p = 0.03). On the other hand, dermatologic symptoms as initial complaint and unspecific symptoms (p = 0.01) were negative predictors for revisit. In only 16% of cases, the revisit did not imply changes in the diagnosis or treatment. Revisits were due to disease-related factors in 34% of cases, physician-related factors in 33%, patients-related factors in 10%, system-related factors in 3% and there were no relationship with the previous visit in 15% (in 5% of cases the cause was unassessable). The diagnosis error most frequently seen was "nonspecific abdominal syndrome". Seventy six percent of revisited patients were admitted. CONCLUSIONS: The revisit rate in our ED is relatively low. Patients being revisited have well-defined clinical and epidemiological profile. The majority of revisited patients require to be admitted.

Appointments and Schedules↗

Acute quadriplegic myopathy with myosin-deficient muscle fibres after liver transplantation: defining the clinical picture and delimiting the risk factors.

BACKGROUND: In the last few years, rare cases of acute quadriplegic myopathy (AQM*) with myosin-deficient muscle fibres occurring after solid organ transplantation has been reported. The aim of the present study was to review all cases of AQM with myosin deficient fibres seen at our institution among a large series of patients after orthotopic liver transplants (OLT), with special attention to clinical aspects and associated risk factors. Additionally, an extensive review of all ultrastructurally demonstrated cases of AQM in transplant recipients is also included. PATIENTS AND METHODS: Among patients involved in 281 consecutive liver transplant procedures performed in a 4-year period, 3 men and 1 woman developed an arreflexic, flaccid quadriplegia in the immediate postoperative period of OLT. After ruling out other causes of weakness, a muscle biopsy was performed and a loss of thick (myosin) filaments was confirmed by ultrastructural analysis in all cases. Accurate clinical, epidemiological, and evolutive data were recorded. RESULTS: Corticosteroids had been used at usual dosage given to liver transplant recipients; all four patients had several intra- and postoperative complications leading to receiving significantly higher amounts of hemoderivates, to develop renal failure in all cases, and to require a significantly higher number of reoperations within a few days after transplantation than our contemporaneous global series of liver transplant recipients. AQM patients required a significantly longer intensive care unit and hospital stay. Muscular recovery was the rule, but currently a mild myopathic gait remains in three patients. These and other reported cases of AQM do not histologically and clinically differ from AQM seen in other critically ill patients who have not had transplants. CONCLUSIONS: Patients with a complicated intra- and postoperative course of OLT who develop newly acquired acute muscle weakness should be suspected as having acute AQM with myosin-deficient muscle fibres. In this setting, differential diagnosis with other causes of weakness should be carried out, because the prognosis of this myopathy is good with early muscle rehabilitation therapy.

Acute Disease↗

[Clinical course of idiopathic inflammatory myopathies: complications, survival and prognostic factors].

OBJECTIVES: To describe the clinical and epidemiological characteristics, complications, survival and prognostic factors of a series of patients with idiopathic inflammatory myopathy (IIM) diagnosed with homogeneous criteria in the same center. PATIENTS AND METHODS: Patients with the diagnosis of IIM during an inclusion period of 20 years were studied. They were classified following the criteria of Bohan and Peter, and Dalakas. Epidemiological, clinical and therapeutical data were obtained in all cases. Evolution and survival were analyzed with the Kaplan-Meier and Cox multiple regression models. RESULTS: One-hundred thirty-five patients with IIM were included in the study: 32 polymyositis (PM), 90 dermatomyositis (DM) and 13 inclusion body myositis (IBM). Forty-six percent presented some complications attributed to the disease or treatment, and 10 with PM, 29 with DM and 3 with IBM died during the follow-up. The probabilities of survival were 86% the first year, 80% the second year, 71% the fifth year, and 57% the tenth year. Infections and cancer were the main death causes. While survival analyses did not show independent risk factors for PM, advanced age, presence of associated neoplasm, raised erythrocyte sedimentation rate (ESR) and muscle relapse were identified as a poor prognostic indicators for DM, whereas raised ESR and long lasting symptoms prior to diagnosis of the myopathy were for IBM. CONCLUSION: In spite of the therapeutic advances, IIM are still diseases with high mortality and morbidity.

Adult↗