J. Villar | Universitat Politecnica de Catalunya (original) (raw)
Papers by J. Villar
Nefrología : publicación oficial de la Sociedad Española Nefrologia
Atherosclerosis Supplements, 2006
Atherosclerosis Supplements, 2009
Minerva anestesiologica, 2011
Unequivocal evidence from both experimental and clinical research has shown that mechanical venti... more Unequivocal evidence from both experimental and clinical research has shown that mechanical ventilation can damage the lungs and initiate an inflammatory response, possibly contributing to extrapulmonary organ dysfunction. This type of injury, referred to as ventilator-induced lung injury (VILI), resembles the syndromes of acute lung injury (ALI) and the acute respiratory distress syndrome (ARDS). VILI can trigger a complex array of inflammatory mediators, resulting in a local and systemic inflammatory response. Substances produced in the lungs can be translocated into the systemic circulation as a result of injury to the pulmonary epithelium and to the capillary endothelium. This type of injury forms the basis for the use of low tidal volumes (5-7 mL/kg of predicted body weight) during mechanical ventilation of patients with ALI/ARDS. The recognition of VILI has prompted a number of investigators to suggest that ALI/ARDS may be, in part, a product of our efforts to mechanically ven...
Minerva anestesiologica, 2001
As a result of the progress in molecular biology and genetics over the last 20 years, now it seem... more As a result of the progress in molecular biology and genetics over the last 20 years, now it seems clear that the pathogenesis of most diseases is influenced by the genotype, the environment and the nature of the process which leads to the injury. Current evidence also suggests that genetic factors are associated with susceptibility to pulmonary diseases. The author reviews some of these complex interactions suggesting that even the inflammatory response during lung injury can be influenced by genetic polymorphisms.
Critical care (London, England), 2001
As in other areas of medicine, the specialty of critical care medicine, which has made important ... more As in other areas of medicine, the specialty of critical care medicine, which has made important contributions in the pathophysiology of critical illness, is facing challenges that must be recognized and addressed in the current century. In this review, we argue that the skill set required to adequately treat critically ill patients will also require knowledge of molecular biology for better diagnosis and treatment. The foundations of molecular biology and genetics are essential for the understanding of the mechanisms of disease. Incorporating molecular biology techniques in the research arsenal of the intensivist will provide the opportunity to dissect out and define the reversible and irreversible intracellular processes giving rise to the major causes of mortality in intensive care units. Two historical paradigms, the cardiopulmonary resuscitation and polymerase chain reaction, summarize how critical care medicine began, and how it could mature in the years to come.
American Review of Respiratory Disease, 1993
This study examined the hypothesis that transient, whole-body hyperthermia would reduce lung dama... more This study examined the hypothesis that transient, whole-body hyperthermia would reduce lung damage and/or mortality in a previously described animal model of acute lung injury. Normal, adult Sprague-Dawley rats were randomly assigned either to a heated (n = 40) or to a sham-heated (n = 49) group. Heated animals were warmed to 41 to 42 degrees C 18 h before intratracheal instillation of phospholipase A2. Forty-eight hours after phospholipase A2 exposure, the two groups were compared in a blinded fashion for mortality rate, PaO2, AaPO2, lung wet/dry weight ratio, alveolar inflammatory cell number, and lung histopathology. Heated, injured animals exhibited a reduced mortality rate and less lung damage than did unheated animals: mortality (zero versus 27%, p < 0.001); AaPO2 (22 +/- 3 versus 36 +/- 15 mm Hg, p < 0.002); lung lavage cell counts (5.3 +/- 3 versus 16.9 +/- 7 x 10(6)/ml, p < 0.05); lung wet/dry weight ratio (4.1 +/- 0.6 versus 5.1 +/- 0.7, p < 0.025); parenchymal lung injury fraction (0.10 versus 0.51, p < 0.001). Transcription and translation of heat shock proteins (HSP70) were examined by Northern and Western analysis. Pulmonary tissue HSP70 mRNA was elevated 1 h after heating. HSP72 protein levels were increased over baseline levels between 12 and 72 h after whole-body hyperthermia, but they were unchanged in sham-heated animals. These data indicate that thermal pretreatment associated with the induction of HSP72 protein synthesis, attenuates tissue damage and mortality in experimental lung injury.
Lancet, Jan 25, 1995
Although meta-analysis of randomised clinical trials is increasingly used, the evaluation of its ... more Although meta-analysis of randomised clinical trials is increasingly used, the evaluation of its ability to predict the results of large trials is not available. We have calculated the relative risks (and 95% confidence intervals) for thirty meta-analyses of different interventions in perinatal medicine, covering 185 randomised controlled trials, but with the largest trial removed. We then compared those results with the result of the largest trial (total sample size more than 1000) done on that intervention and outcome. Twenty-four meta-analyses correctly predicted the direction of the treatment effect, but only eighteen of the thirty were the same both in direction of treatment effect and in statistical significance as the largest trial. There was moderate agreement, beyond chance, between meta-analysis and largest trial results (kappa statistic 0.46-0.53). A meta-analysis demonstrating a protective effect from an intervention of more than 40% had a 60% probability of correctly pr...
Obstetrical & gynecological survey, 1982
Three different types of intrauterine growth retardation can be identified depending on the momen... more Three different types of intrauterine growth retardation can be identified depending on the moment at which supplies to the fetus are diminished. When a reduction in sustenance occurs early in the first trimester of pregnancy, a well-proportioned but growth-retarded baby may be expected. When the negative factors develop around the 30th week of pregnancy, the result is a disproportionately growth-retarded infant. Both types of retardation can be illustrated using longitudinal uterine height and biparietal diameter values and by neonatal anthropometry. Epidemiological examples exist defining factors which produce these two kinds of retardation. The third type occurs when a reduction in food supplies takes place in the last month of pregnancy and causes a depletion of the fetal fat stored. Weight retardation is observed with little or no height impairment. In planning public health activities such as nutrition interventions for developing countries, the type of intrauterine growth ret...
The American journal of clinical nutrition, 1980
American journal of obstetrics and gynecology, Jan 15, 1984
Plasma methotrexate levels were measured in six patients with nonmetastatic and three patients wi... more Plasma methotrexate levels were measured in six patients with nonmetastatic and three patients with "low-risk" metastatic gestational trophoblastic neoplasia who were treated by two different methotrexate regimens. Five patients were treated with 16 cycles consisting of methotrexate, 1 mg/kg (days 1, 3, 5, and 7) followed in 24 hours by citrovorum factor, 0.1 mg/kg (days 2, 4, 6, and 8). Cycles alternated between intravenous and intramuscular administration. Statistical differences in plasma levels were found at 1 and 48 hours between the two routes of administration but probably were not of clinical importance. The plasma levels at the time of citrovorum factor administration were below that necessitating citrovorum factor rescue. Four patients were treated with alternating cycles of intravenous or intramuscular methotrexate, 0.5 mg/kg for 5 consecutive days without citrovorum factor. A total of 15 cycles demonstrated no difference in plasma levels at 1, 12, and 24 hours ...
American journal of obstetrics and gynecology, Jan 15, 1978
International Journal of Gynecology & Obstetrics, 2009
Objectives: To develop and pilot an interactive, evidence-based, e-learning module on the managem... more Objectives: To develop and pilot an interactive, evidence-based, e-learning module on the management of pre-eclampsia and eclampsia for healthcare professionals in India, Mexico and Nigeria. The module focuses on the safe use of magnesium sulphate given the barriers to its use in these countries, which include training inadequacies and a failure to disseminate high quality information.
This paper analyses the schedulability of realtime systems with uncertain knowledge. Fuzzy number... more This paper analyses the schedulability of realtime systems with uncertain knowledge. Fuzzy numbers are used to model parameters describing tasks, providing information about observation of the tasks deadlines at early phases of development. In this paper fuzzy schedulability and a fuzzy optimality criteria are defined and the fuzzy optimality of Deadline Monotonic Scheduling algorithm is proved. It is shown that conventional crisp schedulability analysis can be extended applying both fuzzy arithmetic and interval arithmetic to compute the fuzzy schedulability considering fuzzy execution times, periods, deadlines, blocking times, release jitter, and the existence of aperiodic servers.
Clinical Pulmonary Medicine, 1996
Protocols, 1996
It has been suggested that reduced antenatal care packages or prenatal care managed by providers ... more It has been suggested that reduced antenatal care packages or prenatal care managed by providers other than obstetricians for low risk women can be as effective as standard models of antenatal care. The objective of this review was to assess the effects of antenatal care programmes for low-risk women. We searched the Cochrane Pregnancy and Childbirth Group trials register, reference lists of articles and we also contacted researchers in the field. Date of last search: April 1999. Randomised trials comparing programmes of antenatal care with varied frequency and timing of the visits and different types of care providers. Trial quality was assessed and data were extracted by two reviewers independently. Study authors were contacted for additional information and they were provided with the final version of the review. Nine trials involving over 25000 women were included. Six trials evaluated the number of visits and three trials evaluated the type of care provider. Most trials were of acceptable quality. Moderate reduction in the number of visits was not associated with an increase in any of the negative perinatal outcomes reviewed. However, trials from developed countries suggest that women can be less satisfied with the reduced number of visits and feel that their expectations with care are not fulfilled. Antenatal care provided by a midwife/general practitioner was associated with improved perception of care by women. Clinical effectiveness of midwife/general practitioner managed care was similar to that of obstetrician/gynaecologist led shared care. It appears that a moderate reduction in the number of antenatal care visits with an increased emphasis on the content of the visits could be implemented without any increase in adverse biological perinatal outcomes. Women can be less satisfied with reduced visits. While clinical effectiveness seemed similar, women appeared to be slightly more satisfied with midwife/general practitioner managed care compared to obstetrician/gynaecologist led shared care.
Reviews, 1996
Urinary tract infections, including pyelonephritis, are serious complications that can result in ... more Urinary tract infections, including pyelonephritis, are serious complications that can result in significant maternal and neonatal morbidity and mortality. There is a large number of drugs, and combination of them, available to treat urinary tract infections, most of them tested in non-pregnant women. Attempts to define the optimal antibiotic regimen for pregnancy has, therefore, been problematic. The objective of this review was to try to determine, from the best available evidence from randomized control trials, which agent is most effective for the treatment of symptomatic urinary tract infections during pregnancy in terms of cure rates, recurrent infection, incidence of preterm delivery and premature rupture of membranes, admission to neonatal intensive care unit, need for change of antibiotic, and incidence of prolonged pyrexia. The Cochrane Pregnancy and Childbirth Group trials register, the Cochrane Controlled Trials Register and reference lists of articles were searched. All trials were considered where the intention was to allocate participants randomly to one of at least two alternative treatments for any symptomatic urinary tract infection. Trial quality assessment and data extraction were performed by the two reviewers. Five studies were included. There were no significant differences between studied treatments with regard to cure rates, recurrent infection, incidence of preterm delivery and premature rupture of membranes, admission to neonatal intensive care unit, need for change antibiotic and incidence of incidence of prolonged pyrexia. Although antibiotic treatment is effective for the cure of urinary tract infections, there are insufficient data to recommend any specific treatment regimen for symptomatic urinary tract infections during pregnancy. All of the antibiotics studied were shown to be very effective in decreasing the incidence of outcomes measured. Complications were very rare. All included trials had very small sample sizes to try to detect important differences between treatments. Future studies should evaluate the most promising antibiotics, in terms of class, timing, dose, acceptability, maternal and neonatal outcomes and costs.
Revista de Saúde Pública, 2011
To assess the prevalence of preterm birth among low birthweight babies in low and middle-income c... more To assess the prevalence of preterm birth among low birthweight babies in low and middle-income countries.
Nefrología : publicación oficial de la Sociedad Española Nefrologia
Atherosclerosis Supplements, 2006
Atherosclerosis Supplements, 2009
Minerva anestesiologica, 2011
Unequivocal evidence from both experimental and clinical research has shown that mechanical venti... more Unequivocal evidence from both experimental and clinical research has shown that mechanical ventilation can damage the lungs and initiate an inflammatory response, possibly contributing to extrapulmonary organ dysfunction. This type of injury, referred to as ventilator-induced lung injury (VILI), resembles the syndromes of acute lung injury (ALI) and the acute respiratory distress syndrome (ARDS). VILI can trigger a complex array of inflammatory mediators, resulting in a local and systemic inflammatory response. Substances produced in the lungs can be translocated into the systemic circulation as a result of injury to the pulmonary epithelium and to the capillary endothelium. This type of injury forms the basis for the use of low tidal volumes (5-7 mL/kg of predicted body weight) during mechanical ventilation of patients with ALI/ARDS. The recognition of VILI has prompted a number of investigators to suggest that ALI/ARDS may be, in part, a product of our efforts to mechanically ven...
Minerva anestesiologica, 2001
As a result of the progress in molecular biology and genetics over the last 20 years, now it seem... more As a result of the progress in molecular biology and genetics over the last 20 years, now it seems clear that the pathogenesis of most diseases is influenced by the genotype, the environment and the nature of the process which leads to the injury. Current evidence also suggests that genetic factors are associated with susceptibility to pulmonary diseases. The author reviews some of these complex interactions suggesting that even the inflammatory response during lung injury can be influenced by genetic polymorphisms.
Critical care (London, England), 2001
As in other areas of medicine, the specialty of critical care medicine, which has made important ... more As in other areas of medicine, the specialty of critical care medicine, which has made important contributions in the pathophysiology of critical illness, is facing challenges that must be recognized and addressed in the current century. In this review, we argue that the skill set required to adequately treat critically ill patients will also require knowledge of molecular biology for better diagnosis and treatment. The foundations of molecular biology and genetics are essential for the understanding of the mechanisms of disease. Incorporating molecular biology techniques in the research arsenal of the intensivist will provide the opportunity to dissect out and define the reversible and irreversible intracellular processes giving rise to the major causes of mortality in intensive care units. Two historical paradigms, the cardiopulmonary resuscitation and polymerase chain reaction, summarize how critical care medicine began, and how it could mature in the years to come.
American Review of Respiratory Disease, 1993
This study examined the hypothesis that transient, whole-body hyperthermia would reduce lung dama... more This study examined the hypothesis that transient, whole-body hyperthermia would reduce lung damage and/or mortality in a previously described animal model of acute lung injury. Normal, adult Sprague-Dawley rats were randomly assigned either to a heated (n = 40) or to a sham-heated (n = 49) group. Heated animals were warmed to 41 to 42 degrees C 18 h before intratracheal instillation of phospholipase A2. Forty-eight hours after phospholipase A2 exposure, the two groups were compared in a blinded fashion for mortality rate, PaO2, AaPO2, lung wet/dry weight ratio, alveolar inflammatory cell number, and lung histopathology. Heated, injured animals exhibited a reduced mortality rate and less lung damage than did unheated animals: mortality (zero versus 27%, p < 0.001); AaPO2 (22 +/- 3 versus 36 +/- 15 mm Hg, p < 0.002); lung lavage cell counts (5.3 +/- 3 versus 16.9 +/- 7 x 10(6)/ml, p < 0.05); lung wet/dry weight ratio (4.1 +/- 0.6 versus 5.1 +/- 0.7, p < 0.025); parenchymal lung injury fraction (0.10 versus 0.51, p < 0.001). Transcription and translation of heat shock proteins (HSP70) were examined by Northern and Western analysis. Pulmonary tissue HSP70 mRNA was elevated 1 h after heating. HSP72 protein levels were increased over baseline levels between 12 and 72 h after whole-body hyperthermia, but they were unchanged in sham-heated animals. These data indicate that thermal pretreatment associated with the induction of HSP72 protein synthesis, attenuates tissue damage and mortality in experimental lung injury.
Lancet, Jan 25, 1995
Although meta-analysis of randomised clinical trials is increasingly used, the evaluation of its ... more Although meta-analysis of randomised clinical trials is increasingly used, the evaluation of its ability to predict the results of large trials is not available. We have calculated the relative risks (and 95% confidence intervals) for thirty meta-analyses of different interventions in perinatal medicine, covering 185 randomised controlled trials, but with the largest trial removed. We then compared those results with the result of the largest trial (total sample size more than 1000) done on that intervention and outcome. Twenty-four meta-analyses correctly predicted the direction of the treatment effect, but only eighteen of the thirty were the same both in direction of treatment effect and in statistical significance as the largest trial. There was moderate agreement, beyond chance, between meta-analysis and largest trial results (kappa statistic 0.46-0.53). A meta-analysis demonstrating a protective effect from an intervention of more than 40% had a 60% probability of correctly pr...
Obstetrical & gynecological survey, 1982
Three different types of intrauterine growth retardation can be identified depending on the momen... more Three different types of intrauterine growth retardation can be identified depending on the moment at which supplies to the fetus are diminished. When a reduction in sustenance occurs early in the first trimester of pregnancy, a well-proportioned but growth-retarded baby may be expected. When the negative factors develop around the 30th week of pregnancy, the result is a disproportionately growth-retarded infant. Both types of retardation can be illustrated using longitudinal uterine height and biparietal diameter values and by neonatal anthropometry. Epidemiological examples exist defining factors which produce these two kinds of retardation. The third type occurs when a reduction in food supplies takes place in the last month of pregnancy and causes a depletion of the fetal fat stored. Weight retardation is observed with little or no height impairment. In planning public health activities such as nutrition interventions for developing countries, the type of intrauterine growth ret...
The American journal of clinical nutrition, 1980
American journal of obstetrics and gynecology, Jan 15, 1984
Plasma methotrexate levels were measured in six patients with nonmetastatic and three patients wi... more Plasma methotrexate levels were measured in six patients with nonmetastatic and three patients with "low-risk" metastatic gestational trophoblastic neoplasia who were treated by two different methotrexate regimens. Five patients were treated with 16 cycles consisting of methotrexate, 1 mg/kg (days 1, 3, 5, and 7) followed in 24 hours by citrovorum factor, 0.1 mg/kg (days 2, 4, 6, and 8). Cycles alternated between intravenous and intramuscular administration. Statistical differences in plasma levels were found at 1 and 48 hours between the two routes of administration but probably were not of clinical importance. The plasma levels at the time of citrovorum factor administration were below that necessitating citrovorum factor rescue. Four patients were treated with alternating cycles of intravenous or intramuscular methotrexate, 0.5 mg/kg for 5 consecutive days without citrovorum factor. A total of 15 cycles demonstrated no difference in plasma levels at 1, 12, and 24 hours ...
American journal of obstetrics and gynecology, Jan 15, 1978
International Journal of Gynecology & Obstetrics, 2009
Objectives: To develop and pilot an interactive, evidence-based, e-learning module on the managem... more Objectives: To develop and pilot an interactive, evidence-based, e-learning module on the management of pre-eclampsia and eclampsia for healthcare professionals in India, Mexico and Nigeria. The module focuses on the safe use of magnesium sulphate given the barriers to its use in these countries, which include training inadequacies and a failure to disseminate high quality information.
This paper analyses the schedulability of realtime systems with uncertain knowledge. Fuzzy number... more This paper analyses the schedulability of realtime systems with uncertain knowledge. Fuzzy numbers are used to model parameters describing tasks, providing information about observation of the tasks deadlines at early phases of development. In this paper fuzzy schedulability and a fuzzy optimality criteria are defined and the fuzzy optimality of Deadline Monotonic Scheduling algorithm is proved. It is shown that conventional crisp schedulability analysis can be extended applying both fuzzy arithmetic and interval arithmetic to compute the fuzzy schedulability considering fuzzy execution times, periods, deadlines, blocking times, release jitter, and the existence of aperiodic servers.
Clinical Pulmonary Medicine, 1996
Protocols, 1996
It has been suggested that reduced antenatal care packages or prenatal care managed by providers ... more It has been suggested that reduced antenatal care packages or prenatal care managed by providers other than obstetricians for low risk women can be as effective as standard models of antenatal care. The objective of this review was to assess the effects of antenatal care programmes for low-risk women. We searched the Cochrane Pregnancy and Childbirth Group trials register, reference lists of articles and we also contacted researchers in the field. Date of last search: April 1999. Randomised trials comparing programmes of antenatal care with varied frequency and timing of the visits and different types of care providers. Trial quality was assessed and data were extracted by two reviewers independently. Study authors were contacted for additional information and they were provided with the final version of the review. Nine trials involving over 25000 women were included. Six trials evaluated the number of visits and three trials evaluated the type of care provider. Most trials were of acceptable quality. Moderate reduction in the number of visits was not associated with an increase in any of the negative perinatal outcomes reviewed. However, trials from developed countries suggest that women can be less satisfied with the reduced number of visits and feel that their expectations with care are not fulfilled. Antenatal care provided by a midwife/general practitioner was associated with improved perception of care by women. Clinical effectiveness of midwife/general practitioner managed care was similar to that of obstetrician/gynaecologist led shared care. It appears that a moderate reduction in the number of antenatal care visits with an increased emphasis on the content of the visits could be implemented without any increase in adverse biological perinatal outcomes. Women can be less satisfied with reduced visits. While clinical effectiveness seemed similar, women appeared to be slightly more satisfied with midwife/general practitioner managed care compared to obstetrician/gynaecologist led shared care.
Reviews, 1996
Urinary tract infections, including pyelonephritis, are serious complications that can result in ... more Urinary tract infections, including pyelonephritis, are serious complications that can result in significant maternal and neonatal morbidity and mortality. There is a large number of drugs, and combination of them, available to treat urinary tract infections, most of them tested in non-pregnant women. Attempts to define the optimal antibiotic regimen for pregnancy has, therefore, been problematic. The objective of this review was to try to determine, from the best available evidence from randomized control trials, which agent is most effective for the treatment of symptomatic urinary tract infections during pregnancy in terms of cure rates, recurrent infection, incidence of preterm delivery and premature rupture of membranes, admission to neonatal intensive care unit, need for change of antibiotic, and incidence of prolonged pyrexia. The Cochrane Pregnancy and Childbirth Group trials register, the Cochrane Controlled Trials Register and reference lists of articles were searched. All trials were considered where the intention was to allocate participants randomly to one of at least two alternative treatments for any symptomatic urinary tract infection. Trial quality assessment and data extraction were performed by the two reviewers. Five studies were included. There were no significant differences between studied treatments with regard to cure rates, recurrent infection, incidence of preterm delivery and premature rupture of membranes, admission to neonatal intensive care unit, need for change antibiotic and incidence of incidence of prolonged pyrexia. Although antibiotic treatment is effective for the cure of urinary tract infections, there are insufficient data to recommend any specific treatment regimen for symptomatic urinary tract infections during pregnancy. All of the antibiotics studied were shown to be very effective in decreasing the incidence of outcomes measured. Complications were very rare. All included trials had very small sample sizes to try to detect important differences between treatments. Future studies should evaluate the most promising antibiotics, in terms of class, timing, dose, acceptability, maternal and neonatal outcomes and costs.
Revista de Saúde Pública, 2011
To assess the prevalence of preterm birth among low birthweight babies in low and middle-income c... more To assess the prevalence of preterm birth among low birthweight babies in low and middle-income countries.