Biomedical subjects

L Plaza

Publications and source records attributed to L Plaza.

At least 19 recordsLinked to original sources

PubMed2004

Micromorphological studies on seeds of orobanche species from the iberian peninsula and the balearic islands, and their systematic significance.

BACKGROUND AND AIMS: Previous research has made clear the intrinsic taxonomic difficulties in identifying species in the genus Orobanche. The aim of this study, therefore, was to investigate the systematic utility of seed characteristics. METHODS: Light and scanning electron microscopy was used to examine the seeds of 33 taxa of Orobanche from the Iberian Peninsula and the Balearic Islands. KEY RESULTS: Characters such as size, shape and ornamentation of the seeds were not found to be very useful in differentiation of taxa; however, other characters of the epidermal seed coat cells proved to be very helpful in this respect. Ornamentation of the periclinal walls could be used to discriminate four morphological types. Other features related to the anticlinal walls of the cells, such as thickness, presence/absence of a narrow trough, or relative depth, all contributed to the characterization of a large number of species. CONCLUSIONS: The usefulness of micromorphological studies on seeds of Orobanche in relation to differentiating taxa is demonstrated, and a key is provided to distinguish species or groups of species.

Cell Size↗

PubMed2003

Significance of protein p53 overexpression in the clinical course of high-risk superficial bladder cancer.

OBJECTIVES: This is a retrospective study in which the long-term biological behavior of 67 "high-risk" superficial bladder tumors and the prognostic relevance (prediction of disease recurrence and progression) of the determination of the p53 phenotype in these cases were studied. MATERIAL AND METHODS: 67 tumors with a "high-risk" of progression were selected from the 1,103 transurethral resections for bladder cancer carried out in 640 patients in this center between 1987 and 1992. These included 39 T1G3, 14 Tis (isolated or associated with Ta-T1, non-G3 tumors), and 14 Ta-T1, non-G3 tumors with submucosal lymphatic affection (L+). The median follow-up of these cases was 69.7 months. An immunohistochemical technique with monoclonal antibodies (DO-7) was used to detect the p53 phenotype in paraffin-fixed material. RESULTS: Tumor recurrence occurred in 31 patients (46.3%) and local or distant progression in 14 (20.9%). Radical cystectomy was carried out in 16 (23.9%) cases. p53 overexpression of > or =20% ("p53+") was detected in 40 tumors (59.7%). The rate of recurrence and progression, the disease and progression-free intervals, cancer-specific survival, disease-free survival and progression-free survival were similar in the 3 tumor groups (in all cases, p > 0.05). There were no significant differences in the overexpression of protein p53, using the standard cutoff point of 20% stained nuclei, on comparing the same variables in the whole group of 67 patients (in all cases, p > 0.05). CONCLUSION: The detection of protein p53 was not found to be of use in the retrospective prediction of disease progression or survival in "high-risk" superficial bladder cancer.

Aged↗

PubMed2001

The use of neural networks and logistic regression analysis for predicting pathological stage in men undergoing radical prostatectomy: a population based study.

PURPOSE: Clinical under staging occurs in 40% to 60% of patients who undergo radical prostatectomy for prostate cancer. To decrease under staging several methods of predicting pathological stage preoperatively have been developed based on statistical logistic regression analysis and neural networks. To our knowledge none has been validated in our homogeneous regional patient population to date. We created logistic regression and neural network models, and implemented and adapted them into our practice. We also compared the 2 methods to determine their value and practicality in daily clinical practice. We present the results of our novel approach for predicting pathological staging of prostate adenocarcinoma. MATERIALS AND METHODS: Between 1986 and 1999, 600 white men from the Aragon region of Spain underwent surgery for prostate cancer; of whom 468 were selected for study. Predictive study variables included patient age, clinical stage, biopsy Gleason score and preoperative prostate specific antigen (PSA). The predicted result included in analysis was organ confined or nonorgan confined disease. Data were analyzed by multivariate logistic regression and a supervised neural network (multilayer perceptron and radial basis function). Results were compared by comparing the areas under the receiver operating characteristics curves. RESULTS: We generated 5 logistic regression models. The model created with clinical staging, Gleason biopsy score and PSA distributed in 5 categories (p <0.001) with an area under the receiver operating characteristics curve of 0.840 proved to be most predictive of pathological stage. Similarly of the 6 neural network models evaluated the radial basis function model, which included age, clinical stage, Gleason biopsy score and preoperative PSA distributed in 5 categories with an area under the curve of 0.882, proved the most predictive but not superior to the logistic regression model. The difference in the area under the curves in the 2 chosen models was 0.042 (p = 0.1). CONCLUSIONS: It is possible to generate useful predictive models of organ confined disease using logistic regression or neural networks with high indexes of clinical and statistical validity. However, using these variables neural networks did not prove to be better than logistic regression analysis. Therefore, better predictive variables must be identified, preferably nonlinear characteristics with respect to the probability of organ confined tumor, to generate better predictive models using neural networks.

Aged↗

PubMed1999

[Deep nonpenetrating sclerectomy and open angle glaucoma. Intermediate results from the first operated patients].

PURPOSE: The aim of this retropective study is to evaluate and to compare in glaucoma patients, the mid-term results of the non penetrating deep-sclerectomy (NPDS) with collagen implant or with per operative application of 5 fluorouracile (5 FU). MATERIAL AND METHODS: The aim of the NPDS, a new filtering surgical procedure, is to remove under a scleral flap the Schlemm's canal and the juxtacanalicular trabecular meshwork responsible for the outflow resistance in order to obtain a sub-conjunctival filtration of the aqueous humor with no opening of the anterior chamber. Forty-two open angle glaucoma patients with uncontrolled intra-ocular pressure and with no risk factor of bleb fibrosis, underwent a NPDS. In 27 eyes (group 1) a sponge soaked with 5 FU (50 mg/ml) was applied for 5 minutes in the scleral bed, and in 15 eyes (group-2) a collagen implant (Staar*) was sutured in the scleral bed. A complete ophthalmologic examination was performed on days 1, 8, months 1,2,3 and each 3 months until the end of the follow-up. In case of increased IOP, goniopuncture with the Nd: YAG laser was performed at any time of the post operative period. RESULTS: The mean intra-ocular pressure (IOP) significantly decreased from 23.5 +/- 5.1 mmHg to 15.5 +/- 2.9 at 11.1 +/- 5.6 months follow-up (group 1, p < 10(-3)) and from 22.6 +/- 6.9 Hg to 16.2 +/- 3.9 mmHg at 8.8, 3.6 months follow-up (group 2, p < 10(-3)) with a significant decrease in the medical treatment (p < 10(-3)). The Kaplan Meier probability of success (IOP < or = 20 mmHg without treatment and with no visual field deterioration) at 6 and 12 months was similar in both groups: 57.3% (group 1) and 66.0% (group 2) with a mean decrease in IOP of 30%. Goniopuncture had to be performed in more than one third of case in each group and was effective to control the IOP in half of the cases. No complication related to hypotony or inflammation occured in the post operative period. CONCLUSION: NPDS is an interesting alternative to the classical trabeculectomy since the post operative complications are markedly reduced. However, the mid-term control in IOP appears to be slightly lower. The use of a collagen device does not lead to better control in IOP as compared to the use of a sponge of 5 FU.

Administration, Topical↗

PubMed1997

[Early diagnosis of cancer of the prostate. 5-year analysis].

The authors present the results obtained using a program for early diagnosis in symptomatic patients, within a specific population area. The effectiveness of this diagnosis program for prostate cancer, which is expected to be used also for diagnosis of less advanced stages, is established with the analysis of results obtained in 1000 patients: 42.5% positive biopsies. Biopsy indication in case of suspicious rectal examination and/or PSA over 10 ng/ml is considered useful. There are more reservations towards this indication with PSA values between 4 and 10 ng/ml, where evaluation of other complementary options is considered necessary.

Adult↗

PubMed1997

[Value and sequence of the biopsy of the seminal vesicles and laparoscopic pelvic lymphadenectomy in the staging of cancer of the prostate].

OBJECTIVE: To establish the current indication in our milieu of seminal vesicles (s.v.) biopsy and laparoscopic pelvic lymphadenectomy in prostate cancer. MATERIAL AND METHODS: The prospective study of s.v. biopsy includes 128 patients. Overall efficacy of the technical procedure, incidence of seminal infiltration in relation to clinical staging, PSA, Gleason or the association of both are all analyzed. The second part of the project involves a retrospective statistical study applied to the lymphadenectomy series over a period of 10 years on 202 cases (69 laparoscopic and 133 open ceiling), analyzing several risk factors for nodular invasion. RESULTS: Seminal and nodular infiltration was related to clinical stage, PSA and Gleason. PSA > 20 and Gleason > or = 7 is clinically the most useful association for the diagnosis of seminal infiltration. Increased PSA and Gleason involved greater nodular infiltration; the optimal cut-off point is 40 and 7 respectively. CONCLUSIONS: S.V. biopsy should be performed in T3 stage or in earlier stages with PSA greater or equal to 20 and/or Gleason greater or equal to 7. If biopsy is tumour negative, laparoscopic lymphadenectomy should be performed at T3 stage (regardless of PSA or Gleason), and in < T3 with PSA greater or equal to 40, Gleason greater or equal to 8 and when Gleason is 7 and PSA > 20.

Aged↗

PubMed1995

Clinical and anatomopathological study of 2000 cryptorchid testes.

OBJECTIVE: To establish whether age at the time of surgery and location of the testes help to determine the anatomopathological lesions. PATIENTS AND METHODS: Between 1972 and 1992 surgery was performed on 2000 testes in 1342 children, 658 of whom had bilateral cryptorchidism. The clinical, surgical and anatomopathological records were reviewed. RESULTS: Parametric and non-parametric tests failed to reveal any relation between the tubular fertility index or tubular diameter and the time of surgery or testicular location. CONCLUSION: We cannot recommend a particular age at which surgery should be performed, in relation to the anatomopathological damage.

Adolescent↗

PubMed1994

Outcome of patients with diabetes and unstable angina. A subgroup analysis in the Spanish Multicentre Trial of trifusal in unstable angina. Grupo de Estudio del Trifusal en la Angina Inestable.

We analyzed the clinical characteristics of the 58 diabetic and 218 nondiabetic patients enrolled in the Spanish multicentre trial of trifusal in unstable angina. After 6 months of follow-up, 25 suffered from myocardial infarction or death, 10 of which were diabetics (17.2%) and 15 nondiabetics (6.9%) (P = 0.0146). This difference remained significant after multivariate analysis. We conclude that diabetes is an independent predictor of adverse outcome in patients with medically treated unstable angina.

Aged↗

PubMed1993

Protective effect of triflusal against acute myocardial infarction in patients with unstable angina: results of a Spanish multicenter trial. Grupo de Estudio del Triflusal en la Angina Inestable.

A multicenter, double-blind, placebo-controlled study was carried out to evaluate the effect of a new antiplatelet agent, triflusal (2-acetoxy-4-trifluoromethyl benzoic acid), in the prevention of nonfatal myocardial infarction and cardiac or vascular death (principal end-points) in patients with unstable angina. 281 patients were randomly assigned to triflusal (300 mg t.i.d.; n = 143) or placebo (n = 138). After 6 months of treatment, the incidence of nonfatal acute myocardial infarction was significantly lower in the triflusal than in the placebo group: 6 patients (4.2%) versus 17 (12.3%), p = 0.013. The low number of deaths (2/143 triflusal versus 0/138 placebo recipients) hampered statistical analysis of mortality rates. The need for revascularization was similar in the two groups: 24 patients (16.8%) in the triflusal group and 28 (20.3%) in the placebo group, p = 0.449. In conclusion, the results show that treatment with triflusal can reduce the incidence of myocardial infarction in patients with unstable angina.

Administration, Oral↗

PubMed1992

Determination of heavy metals in human liver.

The levels of Cr (2.49 +/- 0.89 ppm), Mn (5.08 +/- 1.60 ppm), Ni (1.81 +/- 0.95 ppm) and Pb (4.43 +/- 3.12 ppm) were measured in dessicated liver from 44 cases of sudden traumatic death considered as representative of the general population in our area, after ruling out the presence of any underlying disease. Atomic absorption spectrophotometry and electrothermal atomization was carried out after hot, acid digestion, of the dessicated samples. After cancelling the influence of age and cause of death, a significant, positive correlation between Cr/Mn (P = 0.0009; R = 0.493) and Cr/Ni (P = 0.0245; R = 0.347) levels was found.

Adult↗

PubMed1992

Short-term effects of celiprolol on blood pressure and left ventricular performance in hypertensive cardiomyopathy.

Celiprolol (C) is a new selective beta 1-blocker with partial beta 2-agonistic activity. The purpose of this study was to explore its antihypertensive efficacy and its short-term effect on systemic vascular resistances (SVR), cardiac output (CO), left ventricular ejection fraction (LVEF), and left ventricular diastolic performance (LVDP). The Doppler technique was used. In an open-label study, 20 hypertensive patients (15 males, 5 females, age range of 29-68 years) with left ventricular hypertrophy detected by echography were daily treated with 400 mg of C in a single dose, for a period of 4 weeks. C reduced significantly the systolic blood pressure (SBP) and the diastolic blood pressure (DBP) (158 +/- 12 vs. 142 +/- 11 mm Hg, p < 0.05 and 101 +/- 6 vs. 87 +/- 4 mm Hg, p < 0.001, respectively) with a decrease in heart rate (74 +/- 12 vs. 67 +/- 8 beats/min, p = NS). The SVR decreased significantly (2,050 +/- 22 vs. 1,495 +/- 23 dyn/s/cm5, p < 0.001) with a slight but not significant increase in the CO (4.5 +/- 0.69 vs. 5.11 +/- 0.82 L/min). The LVEF did not decrease significantly (58 +/- 5 vs. 56.9 +/- 6%, p = NS) while the LVDP was modified favorably, significantly reducing the early diastolic deceleration time (EDDT) (199 +/- 61 vs. 132 +/- 80 ms, p < 0.01) and reducing the isovolumetric relaxation time (IVRT) (167 +/- 16 vs. 117 +/- 23 ms, p < 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1991

A multicenter double-blind study comparing lovastatin and gemfibrozil in the treatment of primary hypercholesterolemia.

The efficacy and tolerability of lovastatin and gemfibrozil were compared in a randomized double-blind 12-week study including 182 patients with primary hypercholesterolemia, from 7 hospitals in Spain. Inclusion criteria were total-cholesterol of at least 250 mg/dl and triglycerides less than 350 mg/dl. Patients were stratified in two groups: group 1, cholesterol less than 300 mg/dl, and group II, cholesterol equal to or more than 300 mg/dl. Patients were randomized to gemfibrozil (600 mg b.i.d.) or lovastatin (20 mg q.p.m., group I and 40 mg q.p.m., group II). If after 6 weeks of treatment cholesterol remained above 200 mg/dl, lovastatin does were doubled. In group I, lovastatin decreased cholesterol by 20%, LDL-C by 28%, and triglycerides by 17%, and increased HDL-C by 8%. In group II the results were: -26%, -33%, -19% and +6% respectively. The corresponding results with gemfibrozil were: -8%, -9%, -28% and +14% (group I); and -13%, -14%, -33% and +9% (group II). In both groups, lovastatin was more effective in reducing cholesterol and LDL-C (P less than 0.001) and gemfibrozil in reducing triglycerides (P less than 0.05 group I and P less than 0.01 group II). Both drugs were well tolerated. Thus, lovastatin and gemfibrozil are effective lipid-lowering agents; lovastatin has more pronounced effects in patients with hypercholesterolemia.

Adult↗

PubMed1990

Bisoprolol in the treatment of chronic stable angina pectoris.

The purpose of the study was to assess the efficacy and tolerance of the beta1-selective beta-adrenoceptor-blocking agent bisoprolol in patients with chronic stable angina pectoris. A total of 236 outpatients (158 male and 78 female) over 21 years of age (mean age of 57 years and 60 years for men and women, respectively) were included in an open trial of 4 weeks duration. A total of 32.5% of the patients were smokers. After a washout period of at least 1 week, patients were initially treated with 10 mg of bisoprolol o.d. for 2 weeks, after which the dose could be adjusted to 5, 15, or 20 mg in accordance with clinical criteria (efficacy, tolerance). Eighty-eight percent of the patients were maintained on 10 mg of bisoprolol. The frequency of angina attacks was reduced in 89% of all patients: 56% became free of angina attacks. There were no differences in response as related to age and smoking habits. Bisoprolol was well tolerated. Beta-blocker-specific side effects were observed in 12 patients (5.1%). In conclusion, bisoprolol administered once daily appears to be an effective and safe antianginal agent.

Adrenergic beta-Antagonists↗

PubMed1990

[Escape rhythms after ablation of the atrioventricular junction and implantation of a pacemaker].

Escape rhythms characteristics after successful catheter ablation of the atrioventricular junction and intentional complete heart block were compared with those due to others etiologies as well as the advantage of the posterior implantation of a rate responsive pacemaker (VVIR). In 22 patients, 9 men and 13 women, with permanent AV block after fulguration and follow-up periods from 4 to 58 months, escape rhythms data studied during the procedure and at short and long-term periods, showed the following characteristics: 1) Classical parameters of valuation are not as a whole useful to evaluate subsidiary escape rhythms after electrical fulguration of the atrioventricular junction system. 2) The QRS morphology of the escape rhythm exhibited frequently right or left bundle branch block and specially the former. 3) Spontaneous variability of the escape rhythm recovery time makes this parameter unreliable. 4) Electrophysiological parameters previous to the shock and energy delivery do not predict the origin and characteristics of the subsidiary escape rhythms. 5) Active ventricular arrhythmias appearing immediately postshock are unrelated with any subsequent complication. 6) Permanent pacing increases pacemaker dependency at least temporarily. In 15 of 22 patients, a rate responsive multiprogrammable pacemaker controlled by QT interval was implanted. Cardiac performance and life-quality was improved in these patients due to the addition of several factors: 1) Control of the tachyarrhythmias. 2) Elimination of antiarrhythmic drugs and their side-effects on ventricular function. 3) Self-regulation of cardiac rate through permanent stimulation with a QT sensitive rate responsive pacemaker.

Adult↗

PubMed1988

Pathological spectrum of the lung in cases of violent death: Part I. Lesion classification.

The results are presented of the pathological study of the lungs in 66 cases of violent death observing the more frequent types of lesions and establishing 4 different groups of postlesioned pulmonary condition. 1. Inflammatory alveolar lesions without a diffused interstitial involvement (IAL) including contusions or direct aggressions, lobular pneumonias, or bronchopneumonias with a predominance of intra-alveolar inflammatory exudation. 2. Inflammatory alveolar lesions with a diffuse interstitial involvement (IALW) including generalized affectation of the parenchyma with lesions in the capillary structure of the wall. 3. Edemohemorrhagic lesions (EHL) presenting phenomena of capillary congestion with hematic extravasation and interstitial and intra-alveolar edema, without inflammatory involvement. This is the most numerous group and it can constitute the preliminary stage of any other. 4. Unspecific chronic lesions (UCL) not related to the cause of death, being chronically inflammatory and fibrotic alterations of limited interest in our study. We emphasize the importance of the inflammatory involvement of the alveolar wall in the pathogenia of diffuse alveolar damage (DAD) and the aggravation of pulmonary lesions by capillary structure alteration, direct lesion of alveolar epithelium, presence of macrophages, and liberation of certain intracellular enzymes.

Asphyxia↗

PubMed1988

Pathological spectrum of the lung in cases of violent death: Part II. Clinicopathologic correlation.

The correlation between the type of pathological lesion of the lung and the circumstances which encompass their evolution in 66 cases of violent death have been examined. Pulmonary lesions have been classified into four groups. 1. Inflammatory alveolar lesions without a diffuse interstitial involvement (IAL) which result from direct aggressions in subjects of advanced age. 2. Inflammatory alveolar lesions with a diffuse interstitial affectation (IALW) which are more frequent in younger subjects having a higher defense capacity and with severe lesions requiring admission to an intensive care unit. 3. Edemohemorrhagic lesions (EHL) appearing as a precocious lesion at any age. 4. Unspecific chronic lesions (UCL) previous to the aggression and without any relationship to death. The most obvious feature noted was the frequent occurrence of certain types of acute pulmonary lesions indicative of the rapid and extensive capacity of the lung to react to a lesion agent even when death follows rapidly after the aggression. The scarcity of acute interstitial lesions among the older group can be related to a diminution of biological defense activity leading to a less vigorous response; on the contrary, diffuse lesions of the wall seem to be related to an excess of defense mechanisms, determined more by age, severity of lesion, and type of medical assistance received than by a specific type of aggression.

Adult↗

PubMed1987

[IgA nephropathy in childhood].

We review our experience on IgA nephropathy (Berger's disease), defined as the IgA mesangial deposit in the absence of systemic disease. Following these criteria ten patients have been diagnosed which amount to 10% of all biopsied glomerulonephritis in our centre during 1977-1985. These ten patients have been controlled for periods of time ranging from 4 months to 7 years (means = 3 years). After that time, 2 patients have chronic renal failure, in contrast with other pediatric series in which the prognosis is less severe.

Biopsy↗

PubMed1986

Almost total absence of the left ventricular myocardium with dextro-transposition of the great arteries.

The term parchment heart is used to describe partial to nearly complete loss of ventricular myocardium. We report the first case of transposition of the great arteries with almost total absence of left ventricular myocardium. The latter was not recognized and the child underwent Mustard's operation at four months of age. He died on the operating table. At necropsy, the left ventricular wall was 1 mm in thickness; microscopic examination revealed few myocardial fibers within edematous connective tissue.

Heart Defects, Congenital↗