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Biomedical subjects

J Pastor

Publications and source records attributed to J Pastor.

At least 55 records · Page 3Linked to original sources
PubMed1999

ERP correlates of phoneme perception in speech and sound contexts.

To address the question of the existence of a phonetic module for speech perception, event-related potentials were recorded using a 32 channel system in subjects performing a detection task where the target was the ambiguous, noise-like phoneme /f/ presented either among syllables (speech context) or among environmental sounds (non-speech context). Significant context effects were observed on the N2/P3 complex elicited by the target. In particular, a well localized N2b (250-280 ms) appeared at the left temporoparietal sites on the difference wave between contexts as the result of an enhanced negativity when the target was presented among non-speech stimuli. These findings suggest the involvement of the left temporoparietal region in autonomous, modular processes of speech perception.

Acoustic Stimulation↗
PubMed1999

Suramin treatment in hormone- and chemotherapy-refractory prostate cancer.

OBJECTIVES: Suramin, a polysulfonated naphtylurea with anti-growth factor activity, was used in the treatment of metastatic, hormone- and chemotherapy-refractory prostate cancer. Recent studies have proved the effect of suramin on prostate cancer. METHODS: Between March 1990 and January 1994, 27 patients with metastatic prostate cancer were enrolled in this study. Treatment regimen consisted of a loading phase, allowing patients to reach suramin serum levels between 180 and 250 microg/mL using a suramin dose of 1.4 g/m2 at 3-day intervals. Constant suramin serum levels were maintained by a 0.5 to 1-g/m2 dose every 7 to 10 days. Because previous studies showed suramin to have serious toxicity, compromised organ status was excluded by repeated examinations. RESULTS: Six patients did not complete the suramin loading phase because of side effects and were removed from the study. With an average cumulative suramin dose of 14.2 g, 33% of the assessable patients (7 of 21) experienced a more than 50% reduction of prostate-specific antigen (PSA) and/or alkaline phosphatase (AP) serum levels. Mean survival in these suramin-responsive patients was 495 days. Two of these patients experienced a remarkable reduction of metastases in bone scan examinations. Another 48% of the patients (10 of 21) had essentially unchanged AP and PSA serum levels during suramin treatment, indicating stable disease. Mean survival of these patients was 341 days. In 4 patients undergoing suramin treatment, continuous clinical progression of the disease was observed (mean survival 79 days). Toxicity was less or comparable to prior reported studies; the most common side effects were polyneuropathy, allergic skin rash, and vortex keratopathy. CONCLUSIONS: Suramin has limited, but significant, efficacy even in chemotherapy- and hormone-refractory prostate cancer, without serious toxicity.

Aged↗
PubMed1999

[The prognosis following surgical resection of small-cell nonanaplastic bronchogenic carcinoma according to the new staging guideline: an analysis of 1433 patients].

OBJECTIVE: To validate current guidelines for staging bronchogenic lung carcinoma. METHODS: Between 1969 and 1996, small-cell non-anaplastic tumors of bronchogenic carcinoma classified by the recently proposed TNM guidelines of the Spanish Society of Pneumology and Chest Surgery (SEPAR) were resected from 1,433 patients. We used the Kaplan-Meier method to calculate survival and compared the curves using a log-rank test. RESULTS: A stage IA classification was given to 142 patients and IB to 575. Thirty-seven cases were classified IIA and 336 were IIB. Of the latter, 177 were T2N1M0 and 159 were T3N0M0. Two hundred forty-eight patients were in stage IIIA, 54 T3N1M0, 23 T1N2M0, 120 T2N2M0 and 51 T3N2M0. Ninety-five stage IIIB patients were classified as follows: 37 T4N0M0, 35 T4N1M0, and 23 T4N2M0. Five-year survival for IA patients, at 75% was significantly better than the 60% rate for IB patients (p = 0.0021). Likewise, the prognosis for stage IIA, where five-year survival was 57%, was significantly better than for IIB at 39% (p = 0.0434). The prognosis for patients classified as T1NM0 was better than for those classified as T2N1M0, which was 38% (p = 0.0320). The survival of those classified as T3N0M0 (42%) was not significantly different from that of T1N1M0 (p = 0.1754) or T2N1M0 (p = 0.5360) patients. We found no significant difference between T1N1M0 and stage IB (p = 0.3847) patients. Among stage III patients, we observed no difference in survival between stage IIIA and IIIB (p = 0.1914). In stage IIIA, patients classified as T3N2M0 had a significantly lower rate of survival (p = 0.0399). The presence of mediastinal ganglia in stage IIIB was associated with a lower survival rate (p = 0.0328). CONCLUSION: The new guidelines for staging non-small cell anaplastic lung carcinoma do not provide consistent prognoses for homogeneous groups of patients, at least not in certain categories.

Carcinoma, Bronchogenic↗
PubMed1999

[Resection of bronchogenic carcinoma invading the diaphragm].

The prognosis for survival when small cell non-anaplastic bronchogenic carcinoma (SCN-ABC) invades the diaphragm has not been clearly established because the diagnosis is rare. We report a series of eight patients who underwent full resection of SCN-ABC with diaphragm invasion. One died during the postoperative period. Mean survival was eight months for the remaining seven and no patient lived five years. All died as a result of remote metastasis. Given these results, we question whether surgery is the most appropriate treatment for these patients.

Aged↗
PubMed1999

Urinary cotinine and exposure to parental smoking in a population of children with asthma.

BACKGROUND: Studies of the effects of tobacco smoke often rely on reported exposure to cigarette smoke, a measure that is subject to bias. We describe here the relationship between parental smoking exposure as assessed by urinary cotinine excretion and lung function in children with asthma. METHODS: We studied 90 children 4-14 years of age, who reported a confirmed diagnosis or symptoms of asthma. In each child, we assessed baseline pulmonary function (spirometry) and bronchial responsiveness to carbachol stimulation. Urinary cotinine was measured by HPLC with ultraviolet detection. RESULTS: Urinary cotinine concentrations in the children were significantly correlated (P <0.001) with the number of cigarettes the parents, especially the mothers, smoked. Bronchial responsiveness to carbachol (but not spirometry test results) was correlated (P <0.03) with urinary cotinine in the children. CONCLUSION: Passive smoke exposure increases the bronchial responsiveness to carbachol in asthmatic children.

Adolescent↗
PubMed1998

Method for simultaneous measurements of traces of heptadeuterated cholesterol and cholesterol by gas chromatography-mass spectrometry: application in humans.

An assay was developed to quantify deuterated cholesterol (used as a tracer) and cholesterol using gas chromatography-mass spectrometry. Ergosterol and epicoprostanol were used as internal standards. Deuterated cholesterol was quantified by comparing its peak area to that of epicoprostanol and cholesterol to ergosterol. The mean absolute recovery in spiked serum was 99.96%; the precision was in the range 0.16-10.9% and accuracy 90.4-100%; the limit of detection in plasma was 3x10(-5) mmol l(-1). Using two internal standards, the method described herein seems particularly suitable for application in humans i.e., measuring traces of deuterated cholesterol (range: 0-6.26 x 10(-4) mmol l(-1)) along with natural cholesterol (range: 0.065-4.42 mmol l(-1)) in human plasma and lipid fractions postprandially.

Cholesterol↗
PubMed1998

Rapid and sensitive high-performance liquid chromatographic determination of nicotine and cotinine in nonsmoker human and rat urines.

A simple reversed-phase high-performance liquid chromatographic method with paired-ion and UV detection has been developed for the rapid quantification of urinary nicotine and cotinine. A one-step solid-liquid extraction on Extrelut was used. Separation from endogenous substances was achieved with a decreasing flow-rate. With 20 ml of urine for extraction, the limit of quantification was 0.5 ng/ml for cotinine and 5 ng/ml for nicotine; linearity was obtained from 50 to 5000 ng/ml. The intra- and inter-day coefficients of variation were less than 9% for cotinine and 30% for nicotine. Average recoveries for cotinine were 92-100% and 47-86% for nicotine. The present method was applied to the urine analysis of smokers, nonsmoker children, and experimental animals.

Adolescent↗
PubMed1998

Evaluation of a haematological analyser (Sysmex F-800) with equine blood.

A semiautomatic electronic blood cell counter (Sysmex F-800) was evaluated with equine blood, according to the protocol of the International Committee for Standardization in Haematology (ICSH, 1984). The precision and overall reproducibility were acceptable for all the parameters studied except for the platelet count, in which a coefficient of variation of 18.8% and 21.7% was obtained for within and between batch precision and 26.76% for overall reproducibility. Carry-over for the haematocrit value and platelet count was unsatisfactory, thus the use of a blank diluent sample between different analyses was necessary. Linearity of the analyser was acceptable in the range studied. A total of 100 equine blood samples were studied with the Sysmex F-800 and the manual method. The correlations between both Methods were acceptable for all the parameters. In the storage study, the red blood cell count and the haemoglobin concentration were the parameters with longest stability (72 h) at 4 degrees C and 25 degrees C. Platelet count decreased significantly at 3 h post-extraction in those samples stored at 4 degrees C. During the evaluation period, Sysmex F-800 was easy to handle and it is well suited for routine equine blood cell analysis.

Animals↗
PubMed1998

The stress response to repeated capture in mouflon (Ovis ammon): physiological, haematological and biochemical parameters.

Two groups of mouflons (Ovis ammon) were held in captivity to study the effects of repeated capture on physiological, haematological and biochemical parameters. The first one (Group I) was of 6 mouflons captured in the wild, while the second (Group II) was also of 6 mouflons, but which had been in captivity for 3 years. In Group I, body temperature, mature neutrophil count and lactate increased during activity, while red blood cells, haemoglobin, ALT, AST, total lipid, phospholipids, cholesterol, BUN, creatinine, phosphorus and zinc decreased at different times during the study period. In Group II, few statistical differences were observed. Most of these changes were related to stress and reflected a lack of adaptation to repeated handling.

Animals↗
PubMed1998

Nasal granuloma caused by Scedosporium apiospermum in a dog.

A 10-month-old male American Staffordshire terrier was presented to the Autonomous University of Barcelona Veterinary Teaching Hospital because of a 6-month history of a mucopurulent bilateral nasal discharge. The dog had not responded to antibiotics. A follow-up X ray revealed a mixed pattern of osteolysis and increased radiodensity confined to the nasal cavity. Histologic sections of the biopsy specimens revealed the presence of granules containing numerous septate hyphae that were hyaline to pale brown and smooth, one-celled, subspherical-to-elongate conidia that were hyaline to brownish green, and bacteria. Cultures yielded numerous colonies belonging to Scedosporium apiospermum. Susceptibility tests were performed on the isolated strain. The isolate was sensitive to ketoconazole, intermediate to clotrimazole, and resistant to amphotericin B, 5-fluorocytosine, fluconazole, and itraconazole. The dog was treated with oral ketoconazole. During the treatment a general improvement in the lesions was observed. To our knowledge, S. apiospermum has not been implicated previously as an etiologic agent of nasal disease in dogs. This report provides its first description as such.

Animals↗
PubMed1998

Chronic rhinitis associated with herpesviral infection in captive spur-thighed tortoises from Spain.

An epidemic of chronic rhinitis in a population of 50 captive spur-thighed tortoises (Testudo graeca graeca) from Palafrugell (Girona, Spain) is described, in which eight animals died and 12 were euthanatized to perform necropsies and post-mortem studies. The main clinical sign was a bilateral, seromucous rhinitis often accompanied by stomatitis and glossitis. Hematology and serum biochemistry were performed in 33 of the 50 ill animals and in 29 healthy tortoises from three disease-free populations. Lymphocyte count, aspartate aminotransferase (AST) activity, and alpha-globulin levels were significantly higher in the animals from the sick population. The heterophil count was significantly lower in the sick animals. Some of the diseased tortoises also showed a normocytic-normochromic anemia. Lesions were restricted to the respiratory system and oral cavity. Marked epithelial hyperplasia and presence of a severe mixed inflammatory infiltrate in the epithelium of the oral, nasal, and tracheal mucosae were observed. Electron microscopy demonstrated the presence of intracytoplasmic and intranuclear viral particles of the size, shape, and distribution pattern typical of a herpesvirus.

Alpha-Globulins↗
PubMed1998

Effects of lithium heparin and tripotassium EDTA on hematologic values of Hermann's tortoises (Testudo hermanni).

In an effort to define the effect(s) of lithium heparin and tripotassium EDTA on various hematologic parameters in Testudo hermanni, we collected blood samples from 29 clinically healthy adult individuals of both sexes. Portions of each blood sample were transferred to tubes containing either lithium heparin or tripotassium EDTA. The following determinations were made on samples of blood from each anticoagulant: red and white cell counts, packed cell volume, hemoglobin concentration, red cell indices, and differential white cell counts. Due to hemolysis, hematocrits could not be determined from blood samples in EDTA. Further, red blood cell counts were lower in the EDTA samples than in the heparin samples, again due to hemolysis associated with EDTA. However, EDTA did not appear to interfere with hemoglobin determinations. Heparin blood samples provided more optimal blood smears than did EDTA samples, thus differential leucocyte counts were determined only from smears taken from heparin blood samples. Further, thrombocyte and leucocyte aggregation was not observed with heparin use. Thus, heparin is considered the anticoagulant of choice in chelonians for determining red blood cell counts, erythrocyte indices, and hematocrits. When May-Grunwald-Giemsa stain was compared with Diff-Quick, thrombocytes could be more easily differentiated from lymphocytes using the May-Brunwald-Giemsa stain. Heterophil granules seemed to coalese more when Diff-Quick was used. Eosinophils, basophils, and monocytes were similar in appearance with both staining methods.

Animals↗
PubMed1998

[Polyneuropathy in patients with periodic leg movements during sleep].

INTRODUCTION: Periodic legs movements of sleep (PLMS) are rhythmic, standard and repetitive contractions of muscles of the extremities during the sleep. It is known that the patients with restless legs syndrome (RLS) have disorders during the sleep: increase in the latency of the sleep, increased number of arousal, etc.; most of them have also periodic movements of the legs during the sleep. OBJECTIVE: The relationship of the periodic movements of the legs during the sleep with polyneuropathy is not clear. Some authors have found evidence of electrophysiological and pathological of signs of axonal mild polyneuropathy in patients with restless legs syndrome. In this work, we evaluated nine patients that were diagnosed of PLMS, to determine the prevalence of neuropathy in such sample. METHOD: Polysomnography of nocturnal sleep of 7-8 hours was performed, including electromyographic recording of both anterior tibialis muscles; and electroneurographic study of peroneal, sural, ulnar and median nerves. DISCUSSION: Just in none of the nine studied cases were obtained electrophysiological signs of neuropathy; though it has been able to demonstrate the existence of mild alteration of the peripheral nervous system, fundamentally of sensory character; nevertheless, C we think that it would have to be studied the existence of polyneuropathy in all the patients with PLMS in order to discard potentially tractable organic causes.

Adult↗
PubMed1997

Synthesis of epothilones A and B in solid and solution phase.

Epothilones A and B, two compounds that have been recently isolated from myxobacterium Sorangium cellulosum strain 90, have generated intense interest among chemists, biologists and clinicians owing to the structural complexity, unusual mechanism of interaction with microtubules and anticancer potential of these molecules. Like taxol, they exhibit cytotoxicity against tumour cells by inducing microtubule assembly and stabilization, even in taxol-resistant cell lines. Following the structural elucidation of these molecules by X-ray crystallography in 1996, several syntheses of epothilones A and B have been reported, indicative of the potential importance of these molecules in the cancer field. Here we report the first solid-phase synthesis of epothilone A, the total synthesis of epothilone B, and the generation of a small epothilone library. The solid-phase synthesis applied here to epothilone A could open up new possibilities in natural-product synthesis and, together with solution-phase synthesis of other epothilones, paves the way for the generation of large combinatorial libraries of these important molecules for biological screening.

Antineoplastic Agents↗