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Biomedical subjects

M Porta

Publications and source records attributed to M Porta.

At least 19 recordsLinked to original sources
PubMed1992

Myelodysplastic syndromes and malignant solid tumors: analysis of 21 cases.

We studied the association between myelodysplastic syndromes (MDS) and malignancies in a cohort of 155 patients with MDS, 21 of whom presented malignant solid tumors. Myelodysplasia was present after the diagnosis of cancer in eight patients (interval between the diagnosis of both conditions 18 months, median survival 49.5 months), simultaneously with diagnosis in 11 (median survival 8 months), and before malignancy in two patients (interval between the diagnosis of both conditions 47 and 7 months). One patient was given chemotherapy for lung cancer, and three patients received radiotherapy for adenocarcinoma of the kidney and cancer of the prostate. At the time of diagnosis of MDS, nine patients already presented metastatic spread. Fourteen patients died, ten as a result of tumor-related complications and four because of transformation to acute nonlymphocytic leukemia. The analysis of the incidence of malignancy in patients with MDS was statistically significant for males, and the relative risk was significant in both sexes. The results of this study show that MDS patients present a higher incidence of malignant tumors than the general population, that MDS may be of real paraneoplastic significance, and that the occurrence of MDS in cancer patients may be considered to be related to the malignancy rather than an independent phenomenon.

Adenocarcinoma↗
PubMed1992

Carotid percutaneous angioplasty.

Clinical benefit from treatment of symptomatic severe carotid stenoses has been demonstrated recently. The safety profile of endarterectomy, however, justifies the development of alternative techniques as percutaneous transluminal angioplasty (PTA), at least in mild to moderate stenoses. Early results and follow-up data from our series of 44 carotid stenoses treated by PTA are reviewed in this paper, in comparison with other reports from literature. PTA may be beneficial as a therapy of symptomatic internal carotid stenoses, provided its cost/effectiveness has been evaluated by a valid method.

Angioplasty, Balloon↗
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

Sjögren's syndrome: a stepwise approach to the use of diagnostic tests.

One hundred and forty two patients (62 with definite Sjögren's syndrome, 24 with probable Sjögren's syndrome, and 56 in whom Sjögren's syndrome was finally ruled out) were studied. Schirmer's test and rose bengal staining for the diagnosis of keratoconjunctivitis sicca and salivary scintigraphy and a labial biopsy sample for the diagnosis of xerostomaia were studied in all patients. Rose bengal staining showed high specificity (98%) but low sensitivity (55%). All patients with positive rose bengal staining results had associated xerostomia. In the rose bengal staining positive patients, scintigraphy had 100% specificity. A labial biopsy sample showed high sensitivity in the rose bengal staining, salivary scintigraphy positive group, and high specificity in the rose bengal staining positive, salivary scintigraphy negative group. In patients with negative rose bengal staining, salivary scintigraphy showed 96% specificity and 36% sensitivity. A labial biopsy sample had a sensitivity and specificity greater than 90% in rose bengal staining negative patients. Only 29 biopsy samples were needed to achieve a diagnosis of Sjögren's syndrome in 142 patients (20%). Hence the suggested approach may make it unnecessary to take biopsy samples in approximately 80% of patients with suspected Sjögren's syndrome. Using the stepwise approach of first rose bengal staining, then salivary scintigraphy, and eventually a labial biopsy sample in patients with suspected Sjögren's syndrome, the diagnosis is relatively simple.

Adult↗
PubMed1992

Delayed replication of human umbilical vein endothelial cells in high glucose is corrected by L-tyrosine.

Human umbilical vein endothelial cells (HUVEC) cultured in high glucose exhibit delayed replication and colchicine-resistant microtubules. Tubulin dysfunction and stabilization, brought about by acetylation of the NH2-terminal residues, loss of the C-terminal tyrosine and binding of microtubular-associated proteins (MAPs) may be involved in the above phenomenon. The effects of L-tyrosine on HUVEC replication in high glucose were tested and the hypothesis that non-enzymatic glycosylation might impair tubulin depolymerization was also checked by growing the cells in the presence of L-glucose, which binds to intracellular proteins but remains metabolically inactive. After 18 days in culture, the number (mean +/- SEM, n = 7) of HUVEC grown in 28.0 mmol/l D-glucose (435.7 +/- 59.1 x 10(3)) was lower than in 5.6 mmol/l D-glucose (818.3 +/- 75.2 x 10(3)), p < 0.0001. The addition of L-tyrosine 1.7 mmol/l corrected such growth inhibition (623.3 +/- 81.7 x 10(3)), p < 0.0001 vs. D-glucose 28.0 mmol/l, but the cells recovered were less numerous than in physiological glucose alone (p = 0.016). The addition of L-tyrosine to D-glucose 5.6 mmol/l (731.0 +/- 63.2 x 10(3)) did not modify the cell number significantly. HUVEC in extra L-glucose (687.4 +/- 72.0 x 10(3)) were less numerous than in 5.6 mmol/l D-glucose, p = 0.028, but more than in D-glucose 28 mmol/l, p < 0.0001, and were not modified by the addition of L-tyrosine (729.4 +/- 67.1 x 10(3)). HUVEC grown in physiologic and high glucose exhibited specific immunofluorescence for acetylated tubulin and MAPs.(ABSTRACT TRUNCATED AT 250 WORDS)

Cell Division↗
PubMed1992

Clinical assessment of hypermobility of joints: assembling criteria.

We carried out a prospective study to determine the validity of different sets of criteria to define the hypermobility syndrome (HMS), as well as the frequency, reliability and clinical features of HMS items. All consecutive cases of HMS attending the rheumatological outpatient clinic of Hospital del Mar (Barcelona, Spain) constituted the index group (n = 114). A control group of non-HMS rheumatological patients (n = 59) was randomly selected to assess suitable cutoff points and particular HMS item prevalences. Beighton's, Carter's and Rotés' HMS scores correlated very highly among them. Both the correlation coefficients obtained between each pair of sets of HMS criteria and the predictive efficiencies were uniformly high, suggesting high concurrent and predictive validity. All but 2 of the major items were more frequent among women. A basic set of criteria to define HMS is proposed. In relation to previous criteria the new scale shows better internal reliability and homogeneity. Results suggest that it may be suitable for screening studies and in clinical rheumatological settings.

Adult↗
PubMed1992

[Sequential nimodipine-reduced glutathione treatment in alcoholic abstinence syndrome. Preliminary experience].

Alcohol abstinence syndrome (AAS) occurs in alcohol dependent patients a few hours after ceasing to drink, first in the form of gastrointestinal and dysvegetative signs, then with the involvement of neurological functions. The results obtained in 15 patients selected according to DSM III criteria, treated with nimodipine (calcium entry blocker) in the acute phase and with reduced glutathione in the subacute phase are presented. All patients who, during treatment, did not take other drugs, showed a definite, fast improvement in symptoms, especially in neurovegetative symptoms. Administration of nimodipine, which seems capable of reducing the catecholaminergic drive, was very well tolerated. Treatment with reduced glutathione is justified by the fact that the inadequate intake of alcohol is responsible for liver changes and, particularly, for a significant reduction in liver levels of glutathione, a condition that makes the cell more exposed to attack on the part of substances that activate lipoperoxidation processes. The results obtained seem to confirm a protective action on the part of reduced glutathione.

Acute Disease↗
PubMed1991

Cytokine stimulated endothelin release from endothelial cells.

Endothelin release from bovine endothelial cells of the aorta, pulmonary artery, and retinal microvessels was measured in response to various cytokines. Transforming growth factor beta (0.05-5 ng/ml) was found to be a potent stimulator (3-4 fold increase) of endothelin secretion in all three cell types. Tumour necrosis factor alpha (0.1-10 ng/ml) and interferon gamma (8-800 U/ml) had a small (1.5-2 fold increase) but significant effect on endothelin secretion from endothelial cells of large vessels but not the retinal microvessels. Interleukin-1 beta, Interleukin-6 and interleukin-8 at various doses did not affect endothelin secretion. These effects were observed at various time points from 6-24 hrs and indicate that of the cytokines tested, only transforming growth factor beta has a potent effect on endothelin release from endothelial cells of different organs.

Aorta↗
PubMed1991

Production of endothelin by vascular smooth muscle cells.

Endothelin (ET) production by cultured vascular smooth muscle cells isolated from rat and rabbit aortae was measured by a specific radioimmunoassay. Vascular smooth muscle cells released ET at a rate of 0.6 (range of 0.1-1) fmol/10(5) cells/24 h compared to 45 (range of 10-80) fmol/10(5) cells/h for endothelial cells. ET immunoreactivity was confirmed as ET-1 by fast protein liquid chromatography. Calcitonin gene-related peptide (CGRP) and vasoactive intestinal polypeptide (VIP) suppressed basal release of ET by 24-66% from both rat and rabbit vascular smooth muscle. Forskolin and dibutryl-cAMP similarly suppressed ET release by 33-86%, suggesting that increased intracellular cAMP may account for the mechanism of action of CGRP and VIP. In contrast, CGRP and VIP did not have any effect on ET release from endothelial cells. The characteristics and regulation of ET binding sites on vascular smooth muscle cells were measured using [125I]ET-1 as the radioligand. Pretreatment with CGRP, VIP, forskolin, and dibutryl-cAMP increased the ET receptor density on both smooth muscle cell types. The low level production of ET-1 by vascular smooth muscle cells may have an important autocrine function and may be under regulation of neuropeptides localized to perivascular nerves.

Actins↗
PubMed1991

Influence of "diagnostic delay" upon cancer survival: an analysis of five tumour sites.

STUDY OBJECTIVE: The aim was to assess the relationship between survival, tumour stage, and the interval from first symptom to diagnosis (SDI, or duration of symptoms). DESIGN: This was a retrospective follow up study of a cohort of patients registered in the tumour registry of the Hospital del Mar (Barcelona). SETTING: Hospital based tumour registry, with patients derived mainly from the City of Barcelona. PARTICIPANTS: 1247 cases of lung, breast, stomach, colon, or rectal cancer were analysed using survival curves and Cox proportional hazards regression. Subjects (mean age 63.6 years) were followed for a median length of 12.9 months after diagnosis. At the time of diagnosis one fourth of patients had disseminated disease. MEASUREMENTS AND MAIN RESULTS: Based on clinical records, a physician registered the onset time of the first symptom attributable to cancer (from which the SDI is computed), as well as the tumour stage at diagnosis. Other measurements followed standard tumour registry procedures. Overall, the crude mean SDI was 5.15 months (SD 8.03, median 2.03); only 24.5% of cases had an SDI less than a month. Crude mean SDIs by anatomical site were as follows: lung cancer 3.07 months; breast 7.44; stomach 5.34; colon 5.74; rectum 5.03. Tumour extension did not appear to be significantly influenced by SDI, only breast cancer showing a distinct pattern of increased extension with increasing SDI. As expected, the probability of survival decreased monotonically with increasing stage in all sites. Tumour site was also a significant predictor of survival, which at one year ranged from 93% for breast cancer to 28% for lung cancer. However, a longer SDI tended sometimes to be associated with a better chance of survival, a fact that was most apparent in colon cancer. All Cox proportional hazards models showed a consistent picture: SDI was not a significant predictor of survival (age and sex adjusted hazard ratios ranging from 0.97 to 1.01), neither was sex; age did predict survival, and so did site and stage. CONCLUSIONS: The results provide further evidence of a very weak relationship between SDI and tumour stage at diagnosis (except for breast cancer), and between SDI and survival, thus emphasising some limitations within which early clinical detection operates. They also suggest that in addition to reflecting patient and physician behaviour, as well as the functioning of the health system, SDI may be influenced by the biological behaviour of the tumour.

Adult↗
PubMed1991

von Willebrand factor and endothelial abnormalities in diabetic microangiopathy.

We briefly summarize current knowledge on 1) the abnormalities of von Willebrand factor (vWF) as an indicator of endothelial cell (EC) dysfunction in diabetes and 2) the modifications induced in the growth of cultured ECs by high glucose in the incubation media. A MEDLINE search (1986 through Sept. 1989) was performed to update previous relevant references on vWF and ECs in healthy and diabetic subjects. Main data in the literature and personal contributions were scrutinized. Study quality, information, and relevance to the subject were assessed. vWF is synthesized and stored mainly in ECs. Its plasma levels are increased in diabetic microangiopathy but are not influenced by circulating glucose, insulin, or growth hormone, nor do they acutely affect platelet function in diabetes. Supraphysiological concentrations of glucose inhibit the replication of cultured ECs from large vessels via different possible mechanisms but appear to stimulate pathways involved in the activation of capillary ECs. vWF is a possible marker of EC damage in diabetes, and prospective studies will ascertain its role as a predictor for the development of microangiopathy. The possible dichotomy in the response of cultured ECs from large and small vessels to high glucose in the culture media may help explain some of the lesions observed in the walls of arteries and capillaries in diabetes.

Cells, Cultured↗
PubMed1990

Nimodipine in human alcohol withdrawal syndrome--an open study.

The aim of this study was to evaluate the efficacy and tolerability of the DHP Ca2+ antagonist nimodipine in human AWS and post-AWS. Ten hospitalized alcoholics of both sexes with a diagnosis of AWS according to the DSM-III criteria were treated for 3 weeks in monotherapy with nimodipine p.o. at flexible daily dosages. Evaluation of AWS symptoms was performed at baseline and after 3, 5, 7, 10, 14 and 21 days. A statistically significant improvement of AWS was seen at evaluation on day 3, particularly in neurovegetative and psychopathological symptoms, and lasted up to the end of the study. The treatment was well tolerated and no side effects were observed or reported. In this pilot, open study nimodipine proved effective in the treatment of mild-to-moderate AWS. If these data are confirmed in a double-blind study nimodipine could be a rational alternative to benzodiazepines in the treatment of AWS.

Adult↗
PubMed1990

Efficacy of clonidine, guanfacine and methadone in the rapid detoxification of heroin addicts: a controlled clinical trial.

The efficacy of clonidine, methadone, and guanfacine in rapid detoxification of heroin inpatients was assessed in a randomized controlled clinical trial. Signs and symptoms of abstinence and of side effects were analysed in 90 heroin addicts successfully completing a 12-day inpatient trial. All patients fit DSM-III criteria for opioid dependence, the age range being 18 to 36 years. All three drugs were effective in controlling abstinence; however, the course of abstinence was different in the methadone group as compared to the adrenergic agonists, the latter showing limitations in their ability to suppress withdrawal manifestations. While mean number of withdrawal signs and symptoms was significantly lower during days 2 to 5 in the methadone group (p less than 0.01), adrenergic agonists were slightly more effective at the end of the trial. Incidence of side effects was closely related to the dose administered. Hypotensive action of adrenergic agonists was more marked in orthostatic position. The present results suggest that methadone is superior to adrenergic agonists. Between these drugs clonidine appears to be less effective than guanfacine in controlling some withdrawal manifestations, and causes more side effects, mainly of cardiovascular nature.

Adrenergic alpha-Agonists↗
PubMed1989

Water permeability in the human amnion: pH regulation of the paracellular pathway.

Human amnion was mounted, immediately after delivery, as a diaphragm between two lucite chambers and the net transepithelial water movement (Jw) was recorded minute by minute. When Jw was plotted against the applied transepithelial hydrostatic pressure (fetal side positive), in the absence of any other gradient, a linear relationship was observed (Phydr = 0.32 +/- 0.05 cm/s, n = 10). A linear relationship was also found when Jw was measured in the presence of an osmotic gradient, generated by adding (to the maternal side) different concentrations of poly(ethylene glycol) (Mr approximately equal to 3600; reflexion coefficient (sigma) = 1; Posm = 0.015 +/- 0.001 cm/s, n = 10). When sucrose, a paracellular marker, was used as the osmotic probe, the observed sigma was 0.5. Medium acidification in the presence of bicarbonate reduced in the same proportion both the hydrostatic and osmotic permeabilities. The effect was fully reversible, but was not observed when bicarbonate was replaced by Tris. To test the comparative role of transcellular versus paracellular paths, Jw and the [14C]sucrose permeability (Psuc) were simultaneously recorded minute by minute, in the presence of an osmotic or an hydrostatic gradient. In both cases, the percentage reductions in Jw and Psuc induced by medium acidification were similar. Quantification of theoretical and observed values for Jw and Psuc strongly suggests that effects of pH on both the osmotic and hydrostatic flux reflect a modification of the paracellular path.

Amnion↗
PubMed1989

Antibiotic prophylaxis with cefotaxime in gastroduodenal and biliary surgery.

In a multicenter prospective, randomized study, the efficacy of a single preoperative dose of 1 g of cefotaxime for avoiding wound infections was compared with four 2-g doses of cefoxitin. In the study, 1,451 patients with infection risk factors who underwent gastroduodenal or biliary surgery were included, of whom 722 received cefotaxime and 729 cefoxitin. The characteristics of both groups were comparable. The frequency of wound infections in the cefotaxime group was 3.3 percent and in the cefoxitin group, 7.6 percent. The difference was statistically significant. The lowest rate of wound infection (0.63 percent) was achieved when cefotaxime was administered during the last hour before surgery. In both groups, the frequency of infections was directly related to the duration of operation. Hospital stay was, on average, 3 days longer in patients with wound infections. After cost-benefit analysis, we have concluded that cefotaxime treatment results in substantial reduction of costs derived from antibiotic prophylaxis.

Biliary Tract Surgical Procedures↗