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Biomedical subjects

J Alonso

Publications and source records attributed to J Alonso.

At least 19 recordsLinked to original sources
PubMed1992

International Quality of Life Assessment (IQOLA) Project.

The International Quality of Life Assessment (IQOLA) Project is a 4-year project to translate and adapt the widely used MOS SF-36 Health Survey Questionnaire in up to 15 countries and validate, norm, and document the new translations as required for their use in international studies of health outcomes. In addition to the eight-scale SF-36 health profile, the project will also validate psychometrically based physical and mental health summary scores, as well as health utility indexes incorporating SF-36 scales for use in cost-utility studies.

Europe↗
PubMed1992

Clinical gain from improved beam delivery systems.

The feasibility of dynamic conformal heavy charged particle radiotherapy has been investigated at UCLBL, and shows high promise of: 1. an improved therapeutic ratio and 2. reduction in the number of treatment portals required for efficient treatment delivery. Assessment of dose to tumor and critical structures for several anatomical sites have been carried out using a normal tissue complication algorithm developed at LBL. For high-LET charged particle treatment delivery, dynamic conformal therapy using a raster scanned beam with variable modulation and multileaf collimator appears to be the optimal technique for treatment delivery.

Energy Transfer↗
PubMed1992

Covalent binding of urease on ammonium-selective potentiometric membranes.

As part of the development of disposable urea bioselective probes, the covalent binding of urease on ammonium-selective potentiometric membranes has been assessed. Nonactin/bis(1-butylpentyl)adipate/poly(vinylchloride) (PVC) membranes, directly applied to an internal solid contact (conductive epoxy-graphite composite), has been used as a support for covalent immobilization of urease. Two types of all-solid-state construction process have been assayed: thin layers of cellulose acetate (CA) were coated on the PVC ammonium-selective membranes (type 1) and blends of PVC and CA at various ratios were used as ammonium-selective membrane matrices (type 2). Urease was covalently attached to CA via aldehyde groups. These groups were created on the polysaccharide with sodium periodate to which the enzyme was immobilized through a spacer (hexamethylenediamine). The viability of both types of probe for the determination of ammonium ions was assessed after each step of the activation process. Results indicated that type 2 potentiometric probes are altered after the treatment with sodium periodate. Good results were obtained with type 1 probes. Their dynamic concentration range of response to urea was from 2 x 10(-5) to 0.01 M with a sensibility of 50 mV/decade.

Ammonia↗
PubMed1992

Laterality, alternation, and perseveration relationships on the T-maze test.

The T-maze test has been used to study several entirely different issues: spontaneous alternation behavior (SAB), perseveration behavior (PB), and behavioral lateralization. Despite the fact that in this test the behavior studied is always the same one (i.e., side choice), the possible relationships among SAB, PB, and lateralization have not been previously evaluated. The present study investigated the relationships among these functions. The results demonstrated that (a) shock increases PB and lateralization but decreases SAB, (b) practice increases lateralization and decreases SAB but does not modify PB, and (c) there are sex differences for alternation and SAB. Because these functions are expressed by the same behavioral pattern, they must be quantified simultaneously to avoid mistaken conclusions when the T-maze test is used.

Animals↗
PubMed1992

Effect of training on the calf muscle energy metabolism. A 31P-NMR study on four elite downhill skiers challenged with a standardized exercise protocol.

This study evaluates the effects of a 6 months' training period on the bioenergetics of the calf muscle of elite athletes by means of phosphorus-31 Nuclear Magnetic Resonance Spectroscopy (31P-NMR). Four downhill skiers, belonging to the Spanish National Team, performed a standardized exercise protocol using their right leg inside a wide-bore 2.35 Tesla magnet. The inorganic phosphate/phosphocreatine (Pi/PC) ratio and intracellular pH (pHi) were measured at steady-state during an exercise protocol composed of 5 work levels between 20% and 80% of the maximum voluntary contraction (MVC), before and after the training period. The measured values, which were markedly scattered at the beginning, regrouped after training. This was caused by a shift towards lower Pi/PC ratios and by a lower pHi acidification in three of the four subjects. This result suggests that 31P-NMR is a good tool to evaluate changes in the muscle aerobic capacity of athletes induced by training.

Adenosine Diphosphate↗
PubMed1992

Epidemiology of prostatic disorders in the city of Barcelona.

Although disorders of the prostate are among the most prevalent problems in elderly males, little is known about their epidemiological characteristics. The 1986 Barcelona Health Interview Survey (BHIS), a cross-sectional study of a random sample of the noninstitutionalized population of the city, was used to estimate the prevalence of prostatic disorders (PD) and to analyse sociodemographic characteristics, self-perceived health, and use of health services among males reporting PD. Ninety-eight out of 1218 males over 45 years old (8%) reported having PD, the prevalence increasing substantially with age. A pattern of increasing prevalence with decreasing occupational class was found. As compared to subjects not reporting PD, individuals reporting PD reported slightly more restricted activity days (prevalence odds ratio [POR] = 1.28; 95% confidence interval [CI]: 0.52-2.80), more chronic disorders (POR = 4.75; 95% CI: 2.04-13.53), and worse self-perceived health (POR = 1.55; 95% CI: 0.92-2.58). Medical visits and hospitalizations were also higher in the prostatic group (P < 0.05). Men reporting PD appear to constitute a subgroup with increased morbidity and health services use.

Age Factors↗
PubMed1992

Measurement of general health status of non-oxygen-dependent chronic obstructive pulmonary disease patients.

Chronic obstructive pulmonary disease is a prevalent condition causing a high level of disability, and it is one of the leading causes of death. To assess the general health status of moderate to severe Chronic obstructive pulmonary disease patients, we studied 76 male patients attending an outpatient hospital clinic who were not dependent on oxygen and who did not present bronchial obstruction reversibility. We assessed clinical status (dyspnea, six-minute walking distance) and functional respiratory impairment (spirometry, and blood gas analysis) of the patients and also asked them to respond to the Spanish version of the Nottingham Health Profile, a multi-dimensional generic health status measure. Patients scored especially higher than the general population (denoting more level of distress) in energy, physical mobility and sleep Nottingham Health Profile dimensions. The former two dimensions scores had a high correlation with dyspnea (respectively Spearman Rs = 0.60, and Rs = 0.64; P less than 0.01). High levels of sleep disturbances were found for patients reporting low or very low dyspnea level. Health status measurement (Nottingham Health Profile dimension scores) and functional respiratory impairment were not correlated. Results underscore the importance of measuring symptoms carefully when assessing these patients, whose health status is substantially affected by the Chronic obstructive pulmonary disease. They also suggest that it is relevant to assess sleep disturbances in these patients.

Activities of Daily Living↗
PubMed1992

Favorable effects of hyperosmotic reperfusion on myocardial edema and infarct size.

Myocardial water content and infarct size were studied in 39 pigs randomly assigned to a nonintervention group, a group with an intracoronary infusion of a control solution, and a group with a hyperosmotic infusion to 450 mosM by the addition of D-mannitol. The intracoronary solutions were selectively infused into the left anterior descending coronary artery just distal to the occlusion site starting 48 min after occlusion. Reperfusion was performed 3 min later and the infusion rate progressively tapered off over the following 33 min. Multiple myocardial fragments were then obtained in nine pigs, from endocardial, mesocardial, and epicardial regions of the ischemic and control myocardium. Water content measured after 48 h of dessication was significantly greater in the reperfused [530 +/- 7 ml/100 (mean +/- SE) g dry wt] compared with control myocardium (374 +/- 3; P less than 0.0001) and similar in reperfused control and isotonic infusion groups (556 +/- 7 and 543 +/- 8 ml/100 g dry wt); it was 491 +/- 11 with intracoronary D-mannitol infusion, representing 35% less increase (P less than 0.001). In the 30 remaining pigs, area at risk and infarct size were measured 24 h later by in vivo fluorescein and in vitro triphenyltetrazolium chloride. Infarct size was similar in control and in the isotonic reperfused hearts, 6.80 +/- 1.05 and 6.22 +/- 0.76% of ventricular weight, and smaller with D-mannitol, 4.46 +/- 0.46 (P less than 0.05). The ratio of infarct size to area at risk was also smaller [0.415 +/- 0.029 vs. 0.543 +/- 0.052 and 0.547 +/- 0.045 (P less than 0.02)].(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1992

Selective inhibition of the contractile apparatus. A new approach to modification of infarct size, infarct composition, and infarct geometry during coronary artery occlusion and reperfusion.

BACKGROUND: Myocardial reperfusion is associated with calcium overload and cell contracture, mechanisms that may precipitate cell death. In this study, we tested the hypothesis that in vivo inhibition of this contracture could lead to cell preservation in an open-chest large animal model. METHODS AND RESULTS: Regional myocardium function was measured during a selective intracoronary infusion of 2,3-butanedione monoxime (BDM), a specific inhibitor of actin-myosin coupling, in the control state (10 pigs) and in a protocol of a 51-minute coronary occlusion followed by reperfusion (40 pigs). The effects on coronary artery blood flow in the basal state were also studied (seven pigs). Intramyocardial distribution of the infusate during coronary occlusion, myocardial water content after 30 minutes of reperfusion and area at risk, infarct size, type of histological necrosis, and infarct geometry after 24 hours of reperfusion were assessed. Methods used included electromagnetic flowmeter, radiolabeled microspheres, subendocardial sonomicrometers, fluorescein, triphenyl tetrazolium chloride and Masson's trichrome staining, and computer quantification of infarct edges. In the absence of ischemia, BDM infusion inhibited regional shortening in a dose-dependent manner up to full systolic bulging while producing marked regional increase in coronary blood flow. During early reperfusion, BDM reduced end-diastolic length 76% more than the control infusion (p less than 0.05) and increased systolic bulging by 420% compared with no change in control animals. The ratio of infarct size/area at risk was reduced by 31% with BDM (p less than 0.05), with striking modifications of infarct histology and infarct geometry; specifically, the extent of contraction band necrosis was reduced by 63% from 105.5 +/- 18.2 to 39.2 +/- 13.6 mm2 (p less than 0.02), and more patches of necrosis (6.5 +/- 2.1 versus 1.6 +/- 0.4, p less than 0.05) and higher contour (7.7 +/- 1.2 versus 5.03 +/- 0.2, p less than 0.05) and fractal (12.1 +/- 1.3 versus 7.8 +/- 0.2, p less than 0.05) indexes were found. CONCLUSIONS: Selective intracoronary infusion of BDM at doses inhibiting regional wall motion decreased infarct size after reperfusion. The effects of BDM on regional function, the reduction in contraction band necrosis at histology, and the peculiar configuration of these infarcts all suggest that inhibition of contracture can interfere with cell-to-cell progression of myocardial necrosis, supporting a role for contracture in reperfusion-induced cell death.

Actins↗
PubMed1992

Incidence of arterial oxygen desaturation in cardiac patients premedicated with intramuscular scopolamine and morphine.

The effect of a standard preoperative medication combination, morphine and scopolamine, on arterial oxyhemoglobin saturation was measured continuously in 29 patients scheduled for elective coronary artery bypass grafting procedures. On the morning of operation, both before and after administration of preoperative medication, each patient was monitored continuously with a pulse oximeter (SpO2). Patients received 0.05 to 0.11 mg/kg of morphine (mean = 6.0 +/- 2.1 mg) intramuscularly (IM) and 0.2 to 0.4 mg of scopolamine (mean = 0.30 +/- 0.07 mg) IM. The mean arterial blood oxyhemoglobin saturation decreased from 92.0 +/- 1.8% before preoperative medication to 89.0 +/- 3.8% (P greater than .001) after preoperative medication. Forty-five percent of the patients had SpO2 less than 90% for at least 2 minutes, and 21% below 85%. In conclusion, significant arterial oxyhemoglobin desaturation occurred in this group of cardiac surgical patients after preoperative medication with morphine and scopolamine. Prophylactic administration of oxygen with preoperative medication might reduce the incidence of hypoxemia in this group of patients at risk for myocardial ischemia.

Aged↗
PubMed1991

Behavioral lateralization in rats: prenatal stress effects on sex differences.

The possible relationship between human and animal asymmetries is currently a controversial point. In the present study we report that, after practice, rat behavioral asymmetry presents important similarities with human laterality. Thus, rat behavior presents: (1) absolute and population laterality to the same degree and with the same right-bias as that reported for humans; (2) the female has less absolute laterality but similar population laterality to the male; (3) male-female differences for behavioral laterality are modified by prenatal stress as occurs with similar other hormone-regulated behavior.

Analysis of Variance↗
PubMed1991

Comparison of perceived health status and conventional functional evaluation in stable patients with coronary artery disease.

A cross-sectional study of stable coronary hospital patients was carried out to compare perceived health assessment with conventional clinical measures; 93 consecutive patients were studied, 45 of whom had undergone bypass surgery. Exercise tests and clinical functional classification were obtained together with blind concurrent self-responses to the Nottingham Health Profile (NHP), a measure of distress. Coronary arteriography was available for all patients. Patients with negative exercise tests had lower NHP scores (lower levels of distress) than those with positive or inconclusive tests, especially in the energy, pain and physical mobility NHP dimensions (p less than 0.01). High Spearman correlation coefficients were found between exercise performance and energy (rs = -0.51) and pain (rs = -0.36) scores. This correlation was closer than that found with clinical functional class. In these patients, exercise performance closely correlated with perceived distress. Self-perceived health status measures may improve the evaluation of coronary patients based on clinical assessment alone.

Adult↗
PubMed1991

Involvement of lipid mediators in the pathogenesis of experimental nephrosis in rats: its pharmacological modulation.

The administration of a single-injection of Adriamycin (ADR) to rats results in marked proteinuria and glomerular morphological changes that are similar to minimal change disease in humans. We have hypothesized that Adriamycin, by itself or through the release of some mediators from resident glomerular cells, could provoke a damage to epithelial glomerular cells. Sprague-Dawley rats received a single injection of Adriamycin, 7.5 mg/kg bw, allocated randomly in several groups and treated throughout 2 weeks of follow-up. All control nontreated animals developed important nephrotic syndrome and degenerative lesions of epithelial glomerular cells. Isolated glomeruli from animals injected with adriamycin 14 days before synthesized thromboxane (TxB2) and platelet activating factor (PAF) in amounts above the rates of control glomeruli. Animals treated with three structurally different PAF receptor antagonists did not present proteinuria or only to a very low extent (p less than 0.0005). In these rats no alterations in epithelial cells were noted. Furthermore, no significant changes in the TxB2 production were noted in rats treated with BN 52021, a PAF receptor antagonist. Leukotrienes also seem to participate since treatment with a 5-lipoxygenase inhibitor partially corrected proteinuria. Moreover, glomeruli from animals with nephrosis and treated with this compound presented only a discrete reduction in the PAF synthesis. On the whole, these data suggest a key role for PAF in the pathogenesis of adriamycin nephropathy. Other lipid meditors, released in cascade simultaneously or thereafter, could perpetuate the renal damage.

Animals↗
PubMed1990

Two-dimensional spectra of intact tissue: homonuclear Hartmann-Hahn spectroscopy provides increased sensitivity and information content as compared to COSY.

Hartmann-Hahn (HOHAHA) spectroscopy led to good definition of proton spin systems of metabolites such as lactate, (phospho) creatine, and carnosine from a 3-g sample of excised frog gastrocnemius muscle in a 17-min experiment. The sign of the HOHAHA cross-peak intensity appears to provide additional information about interactions between metabolites and their protein binding sites.

Animals↗
PubMed1990

Complete atrioventricular canal and tetralogy of Fallot: surgical management.

Between 1982 and 1989, nine patients with complete atrioventricular (AV) canal and tetralogy of Fallot underwent successful repair of both anomalies. Seven patients had Down's syndrome. One or more previous palliative shunts had been used in six patients. Associated cardiovascular lesions included persistent left superior vena cava (two patients), patent ductus arteriosus with marked stenosis of the left pulmonary artery (one patient). The diagnosis was confirmed by cardiac catheterization and cineangiography. Closure of the ventricular septal defect was performed through a combined right atrial and ventricular approach in each patient. The right ventricular outflow obstruction was relieved with the use of a transannular patch (4), right ventricular infundibular patch (4) or a valved external conduit (1). There were no hospital deaths. One patient died as a result of meningitis 2 years after repair. Progressive left AV valve incompetence developed in one patient requiring valve replacement. A single atrial approach may not provide the best exposure of the subaortic end of the defect. In this regard, we recommend an additional right ventriculotomy in order to ensure safe closure of the septal defect. Although an adequately shaped isolated patch could be sufficient to close the anterior VSD, we favour a separate patch to minimize the possibility of producing subaortic obstruction. A further method to avoid this subaortic stenosis consists of dividing the common anterior leaflet to the right towards the lateral extent of the infundibular septum.

Blood Vessel Prosthesis↗