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J Ramos

Publications and source records attributed to J Ramos.

At least 91 records · Page 5Linked to original sources
PubMed1996

Atopy and nonspecific bronchial responsiveness. A population-based assessment. Spanish Group of the European Community Respiratory Health Survey.

The relative importance of specific immunoresponse in explaining nonspecific bronchial responsiveness (BR) has scarcely been examined. We provide quantitative estimates of the proportion of BR attributable to specific atopy to different common aeroallergens. We used data from a cross-sectional study on a random sample of the general population 20 to 44 yr of age from five Spanish areas. There were 1,816 participants who performed a methacholine challenge and had atopy assessed. BR was defined as a 20% or more fall in FEV1. Atopy was assessed by measuring serum-specific IgE or skin tests to cat, Dermatophagoides pteronyssinus, Cladosporium, Alternaria, timothy grass, olive, birch, Parietaria, or ragweed. The strongest associations between BR and specific IgE response were against timothy grass (prevalence rate ratio = 1.78; 95% confidence interval 1.2 to 2.6), Dermatophagoides pteronyssinus = 1.64 (1.2 to 2.2), and olive = 2.36 (1.5 to 3.7), all after adjustment by age, sex, area of residence, smoking, and a positive response to any of the other eight allergens measured. The population attributable risk of BR for a positive response to any of the nine allergens measured was 20.96% (10.2 to 43.2%) when adjusting for area of residence, age, sex, and smoking. Nonspecific bronchial responsiveness in the general population was found to be related to atopy against single specific allergens, but the population risk attributable to atopy may be lower than previously suggested.

Adult↗
PubMed1996

[Value of percutaneous hepatic biopsy in the diagnosis of presumed benign tumors of the liver].

The purpose of this study was to assess the accuracy of guided hepatic biopsy (GHB) and imaging techniques for presumed benign liver tumours and to determine their impact on surgical treatment. The study was carried out retrospectively in a surgical series of 15 consecutive patients with presumed benign liver tumours. The final diagnosis was 8 cases of focal nodular hyperplasia (FNH), 6 hepatic adenomas (HA) and one association FNH-HA. No morbidity was related to guided hepatic biopsy. All FNH detected on radiologic imaging or pathological examination of the biopsy specimen were true positive diagnoses. This study demonstrates that combined results of imaging techniques and percutaneous GHB could correctly diagnose three quarters of FNH before surgery. GHB is also useful when MRI imaging is indeterminate allowing a conservative approach for undiagnosed FNH.

Adenoma, Liver Cell↗
PubMed1995

Fps1, a yeast member of the MIP family of channel proteins, is a facilitator for glycerol uptake and efflux and is inactive under osmotic stress.

The Saccharomyces cerevisiae FPS1 gene, which encodes a channel protein belonging to the MIP family, has been isolated previously as a multicopy suppressor of the growth defect of the fdp1 mutant (allelic to GGS1/TPS1) on fermentable sugars. Here we show that overexpression of FPS1 enhances glycerol production. Enhanced glycerol production caused by overexpression of GPD1 encoding glycerol-3-phosphate dehydrogenase also suppressed the growth defect of ggs1/tps1 delta mutants, suggesting a novel role for glycerol production in the control of glycolysis. The suppression of ggs1/tps1 delta mutants by GPD1 depends on the presence of Fps1. Mutants lacking Fps1 accumulate a greater part of the glycerol intracellularly, indicating that Fps1 is involved in glycerol efflux. Glycerol-uptake experiments showed that the permeability of the yeast plasma membrane for glycerol consists of an Fps1-independent component probably due to simple diffusion and of an Fps1-dependent component representing facilitated diffusion. The Escherichia coli glycerol facilitator expressed in a yeast fps1 delta mutant can restore the characteristics of glycerol uptake, production and distribution fully, but restores only partially growth of a ggs1/tps1 delta fps1 delta double mutant on glucose. Fps1 appears to be closed under hyperosmotic stress when survival depends on intracellular accumulation of glycerol and apparently opens rapidly when osmostress is lifted. The osmostress-induced High Osmolarity Glycerol (HOG) response pathway is not required for inactivation of Fps1. We conclude that Fps1 is a regulated yeast glycerol facilitator controlling glycerol production and cytosolic concentration, and might have additional functions.

Aquaporins↗
PubMed1995

Control of glucose influx into glycolysis and pleiotropic effects studied in different isogenic sets of Saccharomyces cerevisiae mutants in trehalose biosynthesis.

The GGS1/TPS1 gene of the yeast Saccharomyces cerevisiae encodes the trehalose-6-phosphate synthase subunit of the trehalose synthase complex. Mutants defective in GGS1/TPS1 have been isolated repeatedly and they showed variable pleiotropic phenotypes, in particular with respect to trehalose content, ability to grow on fermentable sugars, glucose-induced signaling and sporulation capacity. We have introduced the fdp1, cif1, byp1 and glc6 alleles and the ggs1/tps1 deletion into three different wild-type strains, M5, SP1 and W303-1A. This set of strains will aid further studies on the molecular basis of the complex pleiotropic phenotypes of ggs1/tps1 mutants. The phenotypes conferred by specific alleles were clearly dependent on the genetic background and also differed for some of the alleles. Our results show that the lethality caused by single gene deletion in one genetic background can become undetectable in another background. The sporulation defect of ggs1/tps1 diploids was neither due to a deficiency in G1 arrest, nor to the inability to accumulate trehalose. Ggs1/tps1 delta mutants were very sensitive to glucose and fructose, even in the presence of a 100-fold higher galactose concentration. Fifty-percent inhibition occurred at concentrations similar to the Km values of glucose and fructose transport. The inhibitory effect of glucose in the presence of a large excess of galactose argues against an overactive glycolytic flux as the cause of the growth defect. Deletion of genes of the glucose carrier family shifted the 50% growth inhibition to higher sugar concentrations. This finding allows for a novel approach to estimate the relevance of the many putative glucose carrier genes in S. cerevisiae. We also show that the GGS1/TPS1 gene product is not only required for the transition from respirative to fermentative metabolism but continuously during logarithmic growth on glucose, in spite of the absence of trehalose under such conditions.

Cell Division↗
PubMed1995

Effect of spatial ability and sex on EEG power in high school students.

Performance at eight cognitive tests and EEG spectral power at rest was computed in 2 groups of men and women, between 17 and 21 years of age, with extreme degrees of spatial ability (SA) evaluated by the spatial relations subtest of the DAT: a low spatial ability group (10 men, 10 women) with scores below percentile 30 and a high spatial ability group (10 men, 10 women) with scores above percentile 80. Ten EEG artifact free samples, 4.096 sec each, were analyzed and absolute (AP) and relative power (RP) were obtained for 5 frequency bands using an FFT. EEG was submitted to principal component analysis and two way ANOVAs. High SA showed lower AP in the entire spectrum with eyes open and closed, and lower alpha 1 RP with eyes open than low SA group regardless of sex. The difference between low and high SA was better explained by high alpha AP at all derivations and high theta AP at right derivations and at left central and occipital regions. Women showed higher beta 1 and beta 2 AP at all derivations except at temporal regions than men regardless of SA scores.

Adolescent↗
PubMed1995

Depot leuprolide acetate versus danazol for treatment of pelvic endometriosis: changes in vertebral bone mass and serum estradiol and calcitonin.

OBJECTIVE: To determine changes in trabecular vertebral bone mass, serum E2, and serum calcitonin during and after therapy of pelvic endometriosis with depot leuprolide acetate (LA) or danazol. DESIGN: Prospective, randomized, double-blind study. SETTING: Academic university hospital and department of obstetrics and gynecology. PATIENTS: Twelve women with symptomatic pelvic endometriosis diagnosed and staged by laparoscopy. INTERVENTIONS: All patients received blinded treatment with either 3.75 mg JM depot LA given every month and daily placebo tablets (n = 6) or 800 mg oral danazol daily with a monthly placebo injection (n = 6) for 24 weeks. MAIN OUTCOME MEASURES: Quantitated computerized tomography of bone density of thoracic 12 to lumbar 4 vertebral bodies were determined before, at the end of 24 weeks of treatment, and 6 and 12 months after completing treatment. Gain or loss of bone mass was based against pretreatment levels. Serial serum levels of E2 and calcitonin before, throughout, and after therapy were compared with changes in bone mass. RESULTS: Bone loss with LA was 14.0% +/- 0.5% (mean +/- SEM), recovering to a deficit of 4.2% +/- 3.8% and 3.3%, 6 and 12 months after stopping therapy. Danazol increased bone by 5.4% +/- 2.2%, with a further gain to 8.2% +/- 3.5% and 7.5%, 6 and 12 months after stopping treatment. Serum E2 levels usually were < 25 pg/mL (conversion factor to SI unit, 3.671) with LA but > 47.3 pg/mL with danazol. Calcitonin levels did not change significantly with either treatment. CONCLUSION: Depot LA produced marked sustained hypoestrogenemia and significant bone loss with incomplete recovery 1 year after stopping treatment. Danazol maintained normoestrogenemia and increased bone mass with the gain maintained even 1 year after stopping therapy.

Adult↗
PubMed1995

Inter- and intrahemispheric EEG correlation during sleep and wakefulness.

Inter- (INTERr) and intrahemispheric (INTRAr) electroencephalographic (EEG) correlations were assessed in eight young male adults during wakefulness with eyes closed before going to sleep, and during stage 2, stage 4 and paradoxical sleep (PS) on the second night spent at the laboratory. Pearson product-moment correlations were calculated between EEG signals of every pair of electrodes (C3, C4, F3, F4, T3, T4) for six bands and for every 0.5 Hz from 1.5 to 15 Hz. Previous results of higher INTERr during sleep compared to during wakefulness were confirmed for the delta and theta bands during stage 2 sleep and PS and for sleep spindles during stage 2 sleep. The present results extend these findings to INTERr between F3 and F4 and during stage 4 sleep. INTRAr of 1.5-6.5 and 11-15 Hz was significantly higher during stages 2 and 4, whereas during PS INTRAr did not change. These data show that cortical changes during sleep are also observed in functional differentiation between cortical sites. Inter- and intrahemispheric differentiation is attenuated during stage 2 and 4 sleep, whereas during PS only inter-hemispheric differentiation is attenuated but intrahemispheric differentiation maintains similar levels of wakefulness. The attenuation of cortical differentiation may be of relevance for the understanding of mental activity changes during sleep.

Adult↗
PubMed1995

Small hepatocellular carcinoma in patients undergoing liver transplantation: detection with CT after injection of iodized oil.

PURPOSE: To assess computed tomography (CT) with iodized oil for depiction of small hepatocellular carcinoma (HCC) before liver transplantation. MATERIALS AND METHODS: Thirty-five consecutive cirrhotic patients underwent CT with iodized oil to determine the presence, number, size, and location of possible nodules. All patients underwent liver transplantation within 4 months after CT. Explanted livers were cut in 8-mm slices that corresponded to axial CT scan planes. Comparison between CT staging and pathologic findings was made. RESULTS: Pathologic studies showed 17 HCC nodules (diameter, 0.9-4.0 cm) in nine of the 35 livers. CT depicted nine of these 17 nodules. Lesion-by-lesion analysis revealed a sensitivity of 53%; CT falsely depicted three additional nodules not confirmed with pathologic findings. Patient-by-patient analysis revealed an 89% sensitivity and an 88% specificity. CONCLUSION: CT with iodized oil, when assessed lesion by lesion, has a low sensitivity. These results must be considered when liver resection is proposed for HCC.

Carcinoma, Hepatocellular↗
PubMed1995

Cross hepatotoxicity between tricyclic antidepressants and phenothiazines.

OBJECTIVE: To describe a case of cross hepatotoxicity between tricyclic antidepressants and phenothiazines. PATIENT: A woman who developed three episodes of drug-induced hepatitis within 3 years as a result of successive treatment with two tricyclic antidepressants, trimipramine and desipramine, and one neuroleptic derivative, cyamemazine. INTERVENTIONS: The drugs were withdrawn after the patient experienced liver dysfunction, although bromazepam was later administered with no side effects. RESULTS: After three episodes of drug-induced hepatitis the patient's serum aspartate aminotransferase and alanine aminotransferase levels returned to normal when the tricyclic antidepressants and cyamemazine were withdrawn. CONCLUSIONS: Trimipramine, desipramine and cyamemazine are related by their chemical structures which include a tricyclic ring. This suggests that this chemical moiety might be involved in the hepatotoxicity of tricyclic antidepressants and phenothiazine derivatives.

Aged↗
PubMed1995

Effect of total sleep deprivation on reaction time and waking EEG activity in man.

Nine paid volunteers were sleep deprived over a period of 40 hours. Every 2 hours during total sleep deprivation (TSD) and after recovery sleep, oral temperature (OT), reaction time (RT) in a vigilance task and electroencephalogram (EEG) with eyes open and closed (C3, C4, T3 and T4) were recorded. Ten artifact-free samples from each condition were Fourier transformed. Absolute power was calculated for six bands. Analyses of variance with deprivation and time of day as factors showed the following significant results: 1) TSD induced an increase in RT, of theta power in all derivations, of beta power in both centrals and a decrease of alpha power with eyes closed; OT was not affected. 2) All bands showed a peak of power at 1800 hours, 2 hours in advance of the OT acrophase at 2000 hours. All variables recovered baseline values after 1 night of sleep. Significant linear correlations of hours of wakefulness with EEG and RT, and of EEG power with OT and RT, were observed. The present findings show a linear increase in EEG power and RT with TSD, and a diurnal oscillation of EEG power, which is independent of TSD.

Adult↗
PubMed1995

[Amyloidosis of the gallbladder. An unusual localization].

We report a rare case of amyloidosis of the gallbladder in a 60-year-old man. This amyloidosis was associated with hepatic amyloidosis and pancreatic adenocarcinoma. To our knowledge, this is the second case reported in the literature and the first associated with neoplastic pathology.

Adenocarcinoma↗