PubMed Health⌕ Search

Biomedical subjects

A Cobos

Publications and source records attributed to A Cobos.

At least 19 recordsLinked to original sources
PubMed2006

Post-operative unwashed shed blood transfusion does not modify the cellular immune response to surgery for total knee replacement.

BACKGROUND: In patients undergoing total knee replacement (TKR), most blood loss occurs post-operatively, and the return of unwashed filtered shed blood (USB) from post-operative drainage may represent an alternative to allogeneic blood transfusion (ABT). We evaluated the impact of USB return on the cellular immune response (CIR) after TKR. PATIENTS AND METHODS: Forty TKR patients, intended to receive post-operative USB, entered the study. Blood samples were obtained before and 6 h, 24 h, 72 h and 7 days after surgery, and from USB, after it had been passed through a 40-microm filter. Full blood cell counts, lymphocyte subsets and immunoglobulins (IgA, IgG, IgM) were measured in all samples. A set of clinical data was collected from each patient. RESULTS: Twenty-four of the 25 patients received a mean of 1.2 USB units and did not need additional ABT (USB group). Twelve of the 15 remaining patients who received neither USB nor ABT served as a control group for the post-operative CIR study. All patients showed a post-operative decrease in T-cell and natural killer (NK) cell counts, but not B-cell counts, and there were no significant differences between the groups with regard to CIR parameters, post-operative infection or hospital stay. CONCLUSIONS: Post-operative salvage and return of USB after TKR does not seem to increase the post-operative infection rate or hospital stay, and does not modify CIR induced by surgery. These findings add to the clinical experience that post-operative USB return, as a source of autologous blood, is safe, and questions the beneficial effect of blood washing.

Aged↗
PubMed2005

Impact of postoperative shed blood transfusion, with or without leucocyte reduction, on acute-phase response to surgery for total knee replacement.

BACKGROUND: In patients undergoing total knee replacement (TKR) most blood loss occurs postoperatively and return of unwashed filtered shed blood (USB) from postoperative drainage may represent an alternative to allogeneic blood transfusion (ABT). We evaluated the impact of USB return, with or without leucocytes, on the acute-phase response (APR) after TKR. PATIENTS AND METHODS: Forty-eight TKR patients, intended to receive postoperative USB, entered the study. Blood samples were obtained before and 6, 24, 72 h and 7 days after surgery, and from the USB before and after it passed through a 40-microm filter (Group F40) or a leucocyte-reduction filter (Group LRF). Haematimetric parameters, APR proteins (albumin, prealbumin, ceruloplasmin, haptoglobin, C-reactive protein), complement C3 and C4, and cytokines (IL-1beta, IL-6, IL-8, IL-10, and TNF-alpha) were measured in all samples. RESULTS: Twenty-eight patients (Group F40=14, Group LRF=14) received a mean of 1.2 USB units, without any clinically relevant incident, and did not need additional ABT. Sixteen out of the 20 remaining patients who received neither USB nor ABT served as a control group for the postoperative APR study. All patients showed the typical postoperative APR profile and there were no significant differences between groups for APR parameters, postoperative complications, or hospital stay. CONCLUSIONS: Postoperative blood salvage and return, with or without a LRF, after TKR does not present any clinically relevant side-effects and does not modify APR induced by surgery. These findings seem to confirm the clinical experience that postoperative USB return is safe and questions the beneficial effect of using LRF.

Acute-Phase Reaction↗
PubMed2004

[Morphometric study with imaging techniques of Trolard's vein and its anastomosis to the superior longitudinal sinus].

OBJECTIVE: The main objective of this work is to allow the anatomical localization of the vein of Trolard (VT) or great anastomotic vein, before neurosurgical approaches to the parietal region. MATERIAL AND METHODS: Thirty four patients were subjected to cerebral angiography. Measurements of different points related to the anatomy of the vein were taken in 41 studies on the lateral projection. A statistical analysis was performed. CONCLUSIONS: The measures obtained are of practical utility to locate the final portion of the vein of Trolard in its anastomotis to the sagittal superior sinus (SLS) for planning neurosurgical approaches to the parietal region.

Adult↗
PubMed2003

Brain afferents to the lateral caudal ventrolateral medulla: a retrograde and anterograde tracing study in the rat.

The ventrolateral medulla (VLM) modulates autonomic functions, motor reactions and pain responses. The lateralmost part of the caudal VLM (VLMlat) was recently shown to be the VLM area responsible for pain modulation. In the present study, the brain sources of VLMlat afferent fibers were determined by tract-tracing techniques. Following injection of cholera toxin subunit B into the VLMlat, retrogradely labeled neurons in the forebrain occurred at the somatosensory, insular, motor, limbic and infralimbic cortices, and at the central amygdaloid nucleus. Retrogradely labeled neurons in diencephalic regions were observed in the lateral hypothalamus, posterior hypothalamus and paraventricular nucleus. In the brainstem, retrograde labeling occurred at the periaqueductal gray, red nucleus, parabrachial area, nucleus raphe magnus, nucleus tractus solitarii, lateral reticular nucleus and dorsal and ventral medullary reticular formation. In the cerebellum, retrogradely labeled neurons occurred at the lateral nucleus. Following injections of the anterograde tracer biotinylated dextran amine (BDA) into the lateral hypothalamus or paraventricular nucleus, anterogradely labeled fibers were mainly observed in the VLMlat. Injections of BDA into the periaqueductal gray, red nucleus or lateral nucleus of the cerebellum resulted in anterograde labeling in the VLMlat and lateral reticular nucleus. The present study gives an account of the brain regions putatively involved in triggering the modulatory actions elicited from the VLMlat. These include areas committed to somatosensory processing, autonomic control, somatic and visceral motor activity and affective reactions. The findings suggest that the VLMlat may play a major homeostatic role in the integration of nociception with other brain functions.

Adjuvants, Immunologic↗
PubMed2001

The efficacy of moxifloxacin in acute exacerbations of chronic bronchitis: a Spanish physician and patient experience.

Chronic bronchitis is a debilitating disease affecting many millions of patients globally. They suffer multiple acute exacerbations each year, often requiring many courses of antimicrobials to enable them to return to normal. The impact of the condition on both the individual patient and society as a whole is considerable and growing; thus antimicrobial therapy should induce rapid and effective outcomes as soon as possible. This open, community-based study of 5737 patients enrolled by over 2000 primary care physicians from across Spain examined the clinical effect of oral moxifloxacin on patients' signs and symptoms of acute exacerbations of chronic bronchitis (AECB) over a 45-day period. The symptoms were assessed using daily diary cards in addition to physician evaluations. Clinical assessment at day 7 showed 93.0% of patients were cured. The patient diary card showed that two-thirds of patients felt better by day 3 or 4. Adverse events were reported in 3.5% of patients in this study, the most common being diarrhoea, nausea and dizziness, and epigastric pain. These reactions were mild to moderate in intensity. There were no patient deaths due to infection during the study. Physicians and patients reported that once-daily moxifloxacin gave fast relief of symptoms of acute exacerbations of chronic bronchitis.

Acute Disease↗
PubMed1999

Which statin is most efficient for the treatment of hypercholesterolemia? A cost-effectiveness analysis.

A review of the cost-effectiveness literature indicated that the hydroxymethylglutaryl coenzyme A-reductase inhibitor fluvastatin is more cost-effective for achieving minor-to-moderate reductions in low-density lipoprotein cholesterol (LDL-C) levels than 3 other statins: lovastatin, pravastatin, and simvastatin. The main goal of this study was to verify the applicability of these conclusions to Spanish health care costs and patterns of resource consumption related to the treatment of hypercholesterolemia. A stochastic simulation model was used to predict both the costs and effects of treating high-risk hypercholesterolemic patients with fluvastatin, lovastatin, pravastatin, or simvastatin. Epidemiologic data were used to find a suitable theoretic probability distribution model for baseline LDL-C values in high-risk hypercholesterolemic patients. The model was then used to generate 10,000 random observations of baseline LDL-C values; the corresponding LDL-C values after a 2-year treatment period were predicted as a function of the baseline value and the percentage reduction expected with a particular statin and dose, according to the results obtained in 2 meta-analyses. The probability of treatment discontinuation was also taken into account using estimates obtained in usual practice. The effects of treatment were expressed as the rate of success in achieving the goal level of LDL-C, as defined in the current Spanish recommendations for the treatment of hypercholesterolemia. The average costs of treatment were computed from both the social and public-financing perspectives, including the cost of lipid-lowering drugs, physician visits, laboratory tests, and days off work, as appropriate. The occurrence of nonscheduled visits and workdays lost because of side effects were taken into account to compute indirect costs relevant to the social perspective. The potential costs of treating side effects were ignored. A cost-effectiveness analysis was performed to compare the cost-effectiveness ratios obtained with each of the 4 statins considered in this study. Model-based predictions of the effects, total costs, and cost-effectiveness ratios were made. Cost-effectiveness ratios were interpreted as the cost per patient meeting the goal of therapy, according to current Spanish recommendations. The data showed that fluvastatin had the lowest cost-effectiveness ratios when LDL-C levels required reduction to < or =25% of baseline levels. In this situation, fluvastatin was more cost-effective than lovastatin, pravastatin, or simvastatin from public-financing and social perspectives.

Administration, Oral↗
PubMed1997

Adjustment of DLCO for hemoglobin concentration.

The equation proposed by Cotes and coworkers is currently considered as the most acceptable to correct carbon monoxide diffusing capacity (DLCO) for hemoglobin concentration [Hb] by both the American Thoracic Society (ATS) and the European Respiratory Society (ERS) guidelines for standardization of DLCO. In a previous study on 24 anemic patients undergoing bone marrow transplantation (1), we found that DLCO is underestimated using the equation of Cotes and coworkers. To further explore this finding, 28 anemic patients ([Hb] = 8.2 +/- 1.0 (SD) g/dl) with chronic renal failure were prospectively studied during the recovery period of anemia (5.4 +/- 3.5 mo). In all 28 subjects, the slope deltaDLCO/delta[Hb] computed as ratio of overall change in DLCO to overall change in [Hb] throughout the study period was 1.40 +/- 0.72 ml CO/min/mm Hg/g/dl. The individual relationship between measured DLCO and [Hb] closely fitted a simple linear regression. The resulting equations for adjustment of DLCO (DLCOadj) to a standard [Hb] of 14.6 g/dl for men and 13.4 g/dl for women are: [equations: see text]. The present adjustment function for DLCO is linear and independent of the observed DLCO values, whereas the formulas previously proposed are curvilinear, DLCO correction varying with the measured DLCO values. For a measured DLCO of 15 ml CO/min/mm Hg and [Hb] ranging from 7 to 12 g/dl, the present DLCO adjustment is higher (by 2.7 ml CO/min/mm Hg, on average) than that proposed by Cotes and coworkers. This difference appears to be relevant for a precise interpretation of DLCO in patients with normocytic anemia in different clinical conditions.

Adult↗
PubMed1996

Effects of erythropoietin on muscle O2 transport during exercise in patients with chronic renal failure.

Erythropoietin (rHuEPO) has proven to be effective in the treatment of anemia of chronic renal failure (CRF). Despite improving the quality of life, peak oxygen uptake after rHuEPO therapy is not improved as much as the increase in hemoglobin concentration ([Hb)] would predict. We hypothesized that this discrepancy is due to failure of O2 transport rates to rise in a manner proportional to [Hb]. To test this, eight patients with CRF undergoing regular hemodialysis were studied pre- and post-rHuEPO ([Hb] = 7.5 +/- 1.0 vs. 12.5 +/- 1.0 g x dl-1) using a standard incremental cycle exercise protocol. A group of 12 healthy sedentary subjects of similar age and anthropometric characteristics served as controls. Arterial and femoral venous blood gas data were obtained and coupled with simultaneous measurements of femoral venous blood flow (Qleg) by thermodilution to obtain O2 delivery and oxygen uptake (VO2). Despite a 68% increase in [Hb], peak VO2 increased by only 33%. This could be explained largely by reduced peak leg blood flow, limiting the gain in O2 delivery to 37%. At peak VO2, after rHuEPO, O2 supply limitation of maximal VO2 was found to occur, permitting the calculation of a value for muscle O2 conductance from capillary to mitochondria (DO2). While DO2 was slightly improved after rHuEPO, it was only 67% of that of sedentary control subjects. This kept maximal oxygen extraction at only 70%. Two important conclusions can be reached from this study. First, the increase in [Hb] produced by rHuEPO is accompanied by a significant reduction in peak blood flow to exercising muscle, which limits the gain in oxygen transport. Second, even after restoration of [Hb], O2 conductance from the muscle capillary to the mitochondria remains considerably below normal.

Adult↗
PubMed1996

Effect of nitric oxide inhalation on respiratory system resistance in chronic obstructive pulmonary disease.

Nitric oxide (NO) has been identified as a neurotransmitter of nonadrenergic noncholinergic bronchodilator nerves. To investigate whether inhaled NO exerts a bronchodilator effect in patients with chronic obstructive pulmonary disease (COPD), we measured the resistance of the respiratory system, using the forced oscillation technique, while breathing NO. Eight patients with COPD (7 men and 1 woman; aged 66 +/- 7 yrs (mean +/- SD); forced expiratory volume in one second (FEV1) 37 +/- 17% of predicted) and eight healthy subjects (7 men and 1 woman; 33 +/- 4 yrs; FEV1 108 +/- 14% pred) were studied. Nitric oxide, at a concentration of 40 parts per million (ppm) in air, was inhaled for 20 min. Total resistance (Rrs) and reactance (Xrs) of the respiratory system, arterial oxygen saturation, heart rate, tidal volume, and breathing frequency were continuously recorded at baseline, and during and after ceasing NO inhalation. Methaemoglobin levels were additionally measured in healthy subjects. At baseline, patients with COPD showed higher Rrs than healthy subjects (Rrs at 10 Hz (Rrs,10) 4.97 +/- 2.19 vs 2.29 +/- 0.65 hPa.L-1.s). During NO inhalation, no significant change in Rrs or in Xrs was observed. Mean variation in Rrs,10 while breathing NO was negligible and similar in the two groups (-0.10 +/- 0.13 hPa.L-1.s in COPD patients and -0.02 +/- 0.13 hPa.L-1.s in healthy subjects). Moreover, there were no differences in oxygen saturation, heart rate, tidal volume and breathing frequency during NO inhalation. Methaemoglobinaemia increased at the end of NO inhalation (from 0.48 +/- 0.18 to 0.81 +/- 0.16%), and this increment remained 10 min later (0.86 +/- 0.31%). From these results, we conclude that inhaled nitric oxide, at a concentration of 40 ppm, exerts no effect on respiratory system resistance in patients with chronic obstructive pulmonary disease or in healthy subjects.

Administration, Inhalation↗
PubMed1996

Nitrendipine and enalapril in the treatment of diabetic hypertensive patients with microalbuminuria.

A trial to study the efficacy, safety and tolerability of nitrendipine and enalapril in the treatment of diabetic hypertensive patients with microalbuminuria (MA) was performed to compare the effects of both drugs in the prevention of the renal impairment. Twenty-eight valid patients [13 with nitrendipine (N) and 15 with enalapril (E) with NIDDM, hypertension (diastolic blood pressure between 90 to 114 mm Hg) and MA (urinary albumin between 30 to 300 mg/24 hr) were recruited in a double blind, randomized trial. Following a placebo run-in period of two to four weeks, all eligible patients were randomly allocated to either N or E treatment. Treatment lasted six months, with two different visits at three and six months in which blood pressure (BP), heart rate (HR), renal function and MA were measured. No statistically significant differences on BP and metabolic parameters were found between both treatment groups. The geometric mean of final glomerular filtration rate (GFR) in the N group was 34.5% higher than in the E group, while the reduction on MA was most important in the E group. Eleven patients reported adverse events (AEs) and there were four dropouts, three of them due to AEs. We conclude that both treatments are a good choice for treating diabetic hypertensive patients with early altered renal function, as they reduce BP without altering metabolic parameters, increase GFR and reduce MA with a low frequency of AEs.

Adult↗
PubMed1995

Chemical and fatty acid composition of meat from Spanish wild rabbits and hares.

The differences in the chemical and fatty acid compositions between the meats of five Spanish wild rabbits (Oryctolagus cuniculus) and five Spanish wild hares (Lepus europaeus) for foreleg, loin, hindleg and perirenal fat have been studied. Only significant differences (P < 0.05) in the meat chemical composition were observed between rabbits and hares for dry matter and fat in loins, and for ash in hindlegs. Significant differences (P < 0.05) between saturated fatty acids in foreleg and perirenal fat and between unsaturated C-18:1 and C-18:2 fatty acids in loins were observed.

Animals↗
PubMed1994

Dopaminergic function in rat brain after oral administration of calcium-channel blockers or haloperidol. A microdialysis study.

Microdialysis technique was used to study the effects of both acute and repeated oral administration of calcium-channel blockers (flunarizine, cinnarizine, verapamil, nifedipine and nicardipine) in dopaminergic function in rat brain and to compare them to the effects of haloperidol. Acute flunarizine, nicardipine or haloperidol increased extracellular levels of dopamine (DA) or metabolites. After repeated (18 days) administration, nicardipine, nifedipine, verapamil or haloperidol increased and flunarizine decreased extracellular striatal levels of dopamine or metabolites. Chronic treatment with calcium-channel blockers or haloperidol failed to block K(+)-evoked release of dopamine. This suggests that the calcium-channel blockers used in this study do not influence calcium entry necessary for DA release. An acute challenge with haloperidol caused either no change or a decrease in extracellular levels of DA or metabolites after repeated administration of calcium-channel blockers or haloperidol. This is considered to be due to the lesser response of dopaminergic neurons because of treatment. A neuroleptic-like mechanism of action together with a decrease in firing activity and/or a reduced dopamine re-uptake of dopaminergic neurons are considered.

Action Potentials↗
PubMed1994

Platelet-activating factor causes ventilation-perfusion mismatch in humans.

We hypothesized that platelet-activating factor (PAF), a potent inflammatory mediator, could induce gas exchange abnormalities in normal humans. To this end, the effect of aerosolized PAF (2 mg/ml solution; 24 micrograms) on ventilation-perfusion (VA/Q) relationships, hemodynamics, and resistance of the respiratory system was studied in 14 healthy, nonatopic, and nonsmoking individuals (23 +/- 1 [SEM]yr) before and at 2, 4, 6, 8, 15, and 45 min after inhalation, and compared to that of inhaled lyso-PAF in 10 other healthy individuals (24 +/- 2 yr). PAF induced, compared to lyso-PAF, immediate leukopenia (P < 0.001) followed by a rebound leukocytosis (P < 0.002), increased minute ventilation (P < 0.05) and resistance of the respiratory system (P < 0.01), and decreased systemic arterial pressure (P < 0.05). Similarly, compared to lyso-PAF, PaO2 showed a trend to fall (by 12.2 +/- 4.3 mmHg, mean +/- SEM maximum change from baseline), and arterial-alveolar O2 gradient increased (by 16.7 +/- 4.3 mmHg) (P < 0.02) after PAF, because of VA/Q mismatch: the dispersion of pulmonary blood flow and that of ventilation increased by 0.45 +/- 0.1 (P < 0.01) and 0.29 +/- 0.1 (P < 0.04), respectively. We conclude that in normal subjects, inhaled PAF results in considerable immediate VA/Q inequality and gas exchange impairment. These results reinforce the notion that PAF may play a major role as a mediator of inflammation in the human lung.

Adolescent↗
PubMed1994

Arterial oxygenation does not predict the outcome of patients with acute respiratory failure needing mechanical ventilation.

One hundred and eighteen patients consecutively submitted to mechanical ventilation during a one year period, and admitted to the Respiratory Intensive Care Unit of the Hospital Clinic of Barcelona, were prospectively studied in order to define the importance of hypoxaemia as a predictor of mortality. Using a discriminant multivariate analysis, the following variables were selected as the best predictors of outcome: 1) the number of associated complications (NAC) on admission; 2) the simplified acute physiologic score (SAPS); 3) oxygenation index (PAO2-AaPO2)/PAO2 + 0.014 positive end-expiratory pressure (PEEP); and 4) the age of the patients. Using these predictors, 84% of the patients were accurately classified as survivors or as nonsurvivors. The partial contribution of each predictor to the model was also assessed using a logistic regression, by eliminating each single predictor and each possible pair of predictors. Using this means of analysis, the NAC and SAPS were the only predictors of mortality. The inclusion of short-term mechanically-ventilated patients did not bias the accuracy of prediction.

Aged↗
PubMed1994

The effect of fat inclusion on diet digestibility in growing rabbits.

Fifty-six California x New Zealand rabbits were used to study the influence of fat addition on nutrient digestibility. Seven diets were formulated to a 24% ADF level: Diet C had no added fat; Diets T, O, and S contained 3% of added beef tallow, oleins, and soybean oil, respectively; and Diets TWS, OWS, and SWS contained the same level and types of fat but also 18% heated whole soybean meal (WS) to increase dietary ether extract (EE) by 3%. After the digestibility trial, rabbits (weighing 2.00 +/- .13 kg) were slaughtered to determine the composition of cecal contents. Fat addition increased digestibility of energy (P < .05) and EE (P < .001). The type of fat only affected (P < .05) EE digestibility. No interaction between fat types and WS was found. Although EE levels of cecal contents increased in diets with added fat (P < .001), they did not negatively affect dietary fiber digestibility. The patterns of fatty acid digestibility in Diet C and in those with soybean oil (S and SWS) were similar; the lowest values were obtained for C16:0 and C18:0. The digestibility of unsaturated fatty acids of C18 increases as its degree of unsaturation increases. Digestibilities of C16:0 and C18:2 were, respectively, lower and higher in the diet with 3% soybean oil than in the diet with 3% tallow.(ABSTRACT TRUNCATED AT 250 WORDS)

Animal Feed↗
PubMed1994

Histopathologic findings in cutaneous lupus erythematosus.

BACKGROUND AND DESIGN: The possible distinction between different types of cutaneous lupus erythematosus (CLE) based on histologic features has been largely debated. This study describes the histopathologic features of three distinct subsets of CLE: chronic, annular-subacute, and papulosquamous-subacute. Biopsy specimens from 92 patients with CLE were examined without the clinical diagnosis being known by the examiners. Of them, 36 clinically demonstrated chronic CLE; 32, annular-subacute CLE; and 24, papulosquamous-subacute CLE. RESULTS: In chronic CLE, the dermal changes (basement membrane thickening, dermal colloid bodies, pilosebaceous atrophy, and periappendageal infiltrate) were more frequent, while in annular-subacute CLE, a more severe vacuolation of the basal layer and a greater number of epidermal colloid bodies were seen. In addition, pilosebaceous atrophy and more severe epidermal damage were almost exclusive to chronic CLE and annular-subacute CLE, respectively. CONCLUSIONS: Although some histologic differences between chronic and annular-subacute CLE exist, histopathologic diagnosis of the CLE subsets can only be accurately established when pilosebaceous atrophy or necrosis of all epidermal layers is observed.

Diagnosis, Differential↗
PubMed1992

Pulmonary aspiration of gastric contents in patients receiving mechanical ventilation: the effect of body position.

OBJECTIVE: To determine if the semirecumbent position (45-degree angle) decreases aspiration of gastric contents to the airways in intubated and mechanically ventilated patients. DESIGN: A randomized, two-period crossover trial. SETTING: Respiratory intensive care unit. PATIENTS: Nineteen patients requiring intubation and mechanical ventilation. INTERVENTIONS: Patients were studied in the supine and semirecumbent positions on two separate days. MEASUREMENTS: After technetium (Tc)-99m sulphur colloid labeling of gastric contents, sequential radioactive counts in endobronchial secretions were measured at 30-minute intervals over a 5-hour period. Samples of endobronchial secretions, gastric juice, and pharyngeal contents were obtained for qualitative bacterial cultures. RESULTS: Mean radioactive counts in endobronchial secretions were higher in samples obtained while patients were in the supine position than in those obtained while patients were in the semirecumbent position (4154 cpm compared with 954 cpm; P = 0.036). Moreover, the aspiration pattern was time-dependent for each position: For the supine position, radioactivity was 298 cpm at 30 min and 2592 cpm at 300 min (P = 0.013); for the semirecumbent position, radioactivity was 103 cpm at 30 min and 216 cpm at 300 min (P = 0.04). The same microorganisms were isolated from stomach, pharynx, and endobronchial samples in 32% of studies done while patients were semirecumbent and in 68% of studies done while patients were in the supine position. CONCLUSIONS: We conclude that the supine position and length of time the patient is kept in this position are potential risk factors for aspiration of gastric contents. Elevating the head of the bed for patients who can tolerate the semirecumbent position may be a simple, no-cost prophylactic measure.

Female↗