PubMed Health⌕ Search

Biomedical subjects

M J Gómez

Publications and source records attributed to M J Gómez.

At least 19 recordsLinked to original sources
PubMed2006

Pilot survey monitoring pharmaceuticals and related compounds in a sewage treatment plant located on the Mediterranean coast.

A one-year monitoring study was performed to evaluate the occurrence, persistence and fate of a group of 14 organic compounds in a sewage treatment plant (STP) located in the south of Spain. These results are part of a more extensive study, financed by the Spanish Ministry of Research with the aim to evaluate the traceability of new pollutants on the Mediterranean coast and to determine the removal efficiency of sewage treatment plants (STP) for these pollutants. The compounds which have been analyzed include pharmaceuticals of various therapeutic categories (ibuprofen, acetaminophen, dipyrone, diclofenac, carbamazepine and codeine), pesticides (chlorfenvinfos and permethrin), caffeine, triclosan, bisphenol A and three of their more relevant metabolites (1,7-dimethylxanthine, carbamazepine 10,11-epoxide and 2,7/2,8-dichlorodibenzo-p-dioxin). An SPE/GC-MS multi-residue analytical method was developed and validated to facilitate simultaneous determination of these compounds in both influent and effluent wastewater. The method provided mean recoveries higher than 75%, with the exception of 2,7/2,8-dichlorodibenzo-p-dioxin, dipyrone and permethrin which exhibited recoveries lower than 22%. The overall variability of the method was below 14%. The method detection limit (LOD) was between 1 and 100 ng l(-1) and precision, which was calculated as relative standard deviation (RSD), ranged from 1.8% to 11.2%. The application of the proposed method has allowed the identification of all the target compounds at mean concentrations which ranged from 0.12 to 134 microg l(-1) in the influent and from 0.09 to 18.0 microg l(-1) in the effluent. The removal efficiencies of the STP for these compounds varied from 20% (carbamazepine) to 99% (acetaminophen), but in all cases resulted insufficient in order to avoid their presence in treated water and subsequently in the environment.

Environmental Monitoring↗
PubMed2005

Skin tests with native, depigmented and glutaraldehyde polymerized allergen extracts.

INTRODUCTION: Dose-response skin prick tests are an important tool to standardise allergen extracts and to evaluate changes in skin test response as a consequence of allergen modifications. OBJECTIVES: To evaluate in vivo and in vitro characteristics of 3 different types of extracts of Phleumpratense, Olea europaea, Parietaria judaica and Dermatophagoides pteronyssinus. MATERIAL AND METHODS: Three types of extracts were used: native unmodified extracts (N), depigmented extracts (DP) (extracts subjected to a mild acid treatment under controlled conditions and dialysis), and a depigmented glutaraldehyde polymerised extract (DPP). Adult patients were skin tested in duplicate with the 3 types of extracts. The dose-response relationship between the geometric mean of the wheal areas and the allergen concentrations was calculated for each patient using regression line analysis. The amount of freeze-dried allergen preparation needed to produce the same wheal size as histamine was calculated in each patient (individual 10 HEP) and for each of the 3 types of extracts. In vitro analysis consisted of major allergen determinations and specific IgE and IgG inhibitions. RESULTS: The respective 10 HEP values for N, DP and DPP preparations were 0.20 mg, 0.15 and 2.11 for D. pteronyssinus. For P. pratense, these values were 0.02 mg, 0.02 and 0.99; for O. europaea 0.15, 0.44 and 4.9; and for P. judaica 0.01, 0.008 and 1.78 mg. CONCLUSIONS: The polymerised depigmented extracts are significantly less allergenic than the corresponding native and depigmented extracts. This could provide a greater safety margin for the administration of higher doses of immunotherapy in a shorter period of time.

Adult↗
PubMed2004

Comparative study of analytical methods involving gas chromatography-mass spectrometry after derivatization and gas chromatography-tandem mass spectrometry for the determination of selected endocrine disrupting compounds in wastewaters.

Two GC-MS methods, based on the application of N,O-bis(trimethylsilyl)trifluoroacetamide-derivatization-GC-MS (selected-ion monitoring) and GC-MS-MS without derivatization, respectively, were optimised and applied to the determination of a group of five selected endocrine disrupting compounds (EDCs) in wastewaters. Both methods included solid-phase extraction with Oasis HLB cartridges allowing an enrichment factor for wastewater samples of 100-fold. The investigated EDCs were estrone, 17beta-estradiol, 17alpha-ethynylestradiol, 4-tert-octylphenol and bisphenol A. Results obtained from the validation studies yielded comparable results in both cases. Recoveries in spiked wastewaters at 50 ng/l were higher than 90% for all the compounds, except for 4-tert-octylphenol (75%). Repeatability and reproducibility were adequate, varying from 1.6 to 14%, except for estrone which reproducibility was 28% when the derivatization-GC-MS method was applied. Limits of detection calculated ranged from 2.5 to 27.5 ng/l with differences between both methods from 1.1 (estrone) to 10.4 (bisphenol A) times. Both methods were successfully applied to the analysis of the target compounds in sewage treatment plant influents and effluents. Traces of bisphenol A, 4-tert-octylphenol, estrone and 17beta-estradiol were detected at concentration levels ranging from 13.3 to 1105.2 ng/l.

Endocrine Glands↗
PubMed2004

Enumeration of Clostridium perfringens spores in groundwater samples: comparison of six culture media.

In order to investigate the ability of Fluorocult-supplemented TSC agar (TSCF (Fluorocult supplemented TSC-agar): prepared from Tryptose Sulfite Cycloserine Agar Base (Merck), D-cycloserine (Fluka Chemika, USA), and fluorocult TSC-Agar supplement (Merck)) for detecting spores of Clostridium perfringens in water, we analyzed groundwater samples, pretreated by heating to 80 degrees C/5 min, using this fluorogenic medium together with five other media: mCP agar (Panreac; Cultimed), TSC agar (Merck, Germany), TSN agar (Merck), and SPS agar (BBL, USA) by the membrane filtration technique, and Wilson-Blair agar (WB) following the still-in-force Spanish official method. Variance analysis of the data obtained shows statistically significant differences in the counts obtained between media employed in this work. The C. perfringens spore counts on mCP agar were significantly lower (P<0.05) than the corresponding values of TSC, TSCF, SPS, and WB media. No statistically significant differences were found between C. perfringens spore counts on TSCF compared with those of other methods used. On the other hand, the identification of typical and atypical colonies isolated from all media demonstrated that fluorogenic TSC agar was the most specific medium for C. perfringens spore recovery in groundwater samples. Additionally, the results obtained indicate that mCP agar, which is the reference method in the European Union, is not suitable medium for recovering C. perfringens spores from groundwater samples.

Clostridium perfringens↗
PubMed2004

Tissue factor expression is decreased in monocytes obtained from blood during Mediterranean or high carbohydrate diets.

BACKGROUND: Mediterranean and high carbohydrate diets play a dominant role in the prevention of atherosclerosis as a result of their lipid lowering effect. However, diets can also have a protective effect in other ways, such as modulating tissue factor expression in circulating monocytes. METHODS AND RESULTS: Forty-one subjects participated in this randomised crossover study consisting of three dietary periods: a saturated fat enriched diet (SFA), a low fat and high carbohydrate diet (CHO), and a Mediterranean diet. Plasma levels of total cholesterol, triglycerides, low density lipoprotein (LDL-C) and high density lipoprotein (HDL-C) were determined at the end of each dietary period, as was the expression of tissue factor (TF) in circulating monocytes isolated from blood samples. Total cholesterol, LDL-C, HDL-C and TF expression were lower after the Mediterranean and high carbohydrate diets than after the SFA diet, and there was a positive correlation between LDL-C levels and monocyte TF expression. CONCLUSIONS: High carbohydrate and Mediterranean diets reduce the expression of TF in circulating monocytes.

Adult↗
PubMed2001

Evaluation of fluorogenic TSC agar for recovering Clostridium perfringens in groundwater samples.

Clostridium perfringens is widely recognised as a reliable water pollution indicator. Since several media can be employed for the membrane filtration enumeration of this microorganism, the main aim of this work was to investigate the ability of fluorocult-supplemented TSC-agar (Merck) for recovering Cl. perfringens from public springs used for direct human consumption. Cl. perfringens recovery was also performed on mCP agar (Cultimed) according to Directive 98/83 as well as on TSC-Agar (Merck), TSN-Agar (Merck) and SPS-Agar (BBL) media. Variance analysis of data obtained showed no statistically significant differences in the counts obtained among all media employed in this work. However, the Cl. perfringens recovery efficiencies with TSC and fluorogenic TSC agars were significantly greater (P = < 0.05) than the corresponding values of mCP and TSN media. On the other hand, the identification of typical and atypical colonies isolated from all media demonstrated that fluorogenic TSC agar was the most specific medium for Cl. perfringens recovery in groundwater samples (85.3% of typical colonies and 82.8% of atypical colonies confirmed). In summary, the membrane filtration technique with fluorogenic TSC agar showed the best performance characteristics of all the media tested as judged by their recovery efficiency and specificity in these water samples.

Agar↗
PubMed2001

Evaluation of Coli-ID and MUG Plus media for recovering Escherichia coli and other coliform bacteria from groundwater samples.

Several chromogenic media for detecting coliform bacteria in water are commercially available including Coli ID medium (ID) (bioMérieux) and MUG Plus cefsulodin agar (MP) (Laboratorios Microkit, S.L.). Since little is known about the performance of these media, we have evaluated their usefulness for recovering Escherichia coli and other coliform organisms in groundwaters used for direct human consumption. Variance analysis of obtained data showed that no statistically significant differences in counts of E. coli and other coliforms on ID and MP media compared with reference methods. However, the evaluation of sensitivity and recovery efficiency of both media showed that the two chromogenic media were more sensitive and significantly more efficient (P = < 0.05) than reference medium for detecting coliforms in groundwater. However, the identification of 400 typical and atypical colonies isolated from ID and MP media demonstrated a higher specificity when using ID for coliforms and E. coli. In summary, the two chromogenic media evaluated could be used as alternative methods to reference media for detecting and recovering coliform bacteria in groundwater samples. MP agar was more sensitive and efficient than ID agar whereas the latter was more specific and selective.

Agar↗
PubMed2001

[Bacteriological techniques for the design and identification of Mycobacterium tuberculosis].

This review summarizes the classic bacteriologic techniques used to diagnose M. tuberculosis and others mycobacterial infection. This methodology involves special methods such as staining, recovery in culture media and identification by phenotypic and biochemical characteristics. New methods for rapid diagnosis are been developed and the laboratories should be alert in order to incorporated them in their routine.

Bacterial Typing Techniques↗
PubMed2000

Utility of fluorine-18-fluorodeoxyglucose positron emission tomography in differentiated thyroid carcinoma with negative radioiodine scans and elevated serum thyroglobulin levels.

BACKGROUND: This study aimed to determine the role of fluorine-18-fluorodeoxyglucose positron emission tomography (FDG-PET) in the follow-up of patients who underwent total thyroidectomy and iodine-131 ((131)I) ablation therapy for differentiated thyroid cancer and presented increased thyroglobulin levels with negative (131)I and thallium-201 ((201)Tl) scans. METHODS: Two patients with follicular carcinoma and eight with papillary tumors underwent total thyroidectomy and (131)I therapy until the (131)I scan was negative. (131)I and (201)Tl scans were performed with negative results in all cases, while serum thyroglobulin measurements were all positive with negative thyroglobulin autoantibodies. One week after the (131)I scans, all the patients underwent FDG-PET whole-body scans. RESULTS: The FDG-PET scan detected in 4 patients, a single focal increase of FDG uptake in one lymph node metastasis (subsequently confirmed histologically); in 1 patient, multiple pathological focal uptakes in brain, neck, and chest; and in 1 patient, two mild focal uptakes in the mediastinum, close to the tracheal branch. In 2 other patients, pathological FDG uptakes in cervical spine and mediastinum were not confirmed by other imaging techniques, and in the 2 remaining patients the scan results were inconclusive. The sensitivity of FDG-PET whole-body scan for detecting metastatic thyroid cancer was 60%. CONCLUSIONS: This study indicates that the FDG-PET whole-body scan is a useful tool in the follow-up of patients with differentiated thyroid cancer, negative (131)I and (201)Tl scans and elevated serum thyroglobulin levels. The FDG-PET scan detects metastatic disease in 60% of patients with differentiated thyroid cancer, enabling surgical therapy to be performed on accessible lesions.

Adenocarcinoma, Follicular↗
PubMed2000

GP frequent attendance in Liverpool and Granada: the impact of depressive symptoms.

BACKGROUND: Frequent attendance in general practice increases workload and affects doctor-patient relationships. It is a complex phenomenon, but patients' psychological problems appear to be important. AIM: To assess whether frequent attendance is more likely to be associated with depressive symptoms than with physical health problems. METHOD: The study was carried out in two general practices: one in Liverpool and one in Granada. Subjects comprised 127 frequent attenders (FAs) plus 175 matched controls, stratified by age and sex. Measures included demographic factors, Beck Depression Inventory (BDI), self-reported health, and current health problems classified by ICHPPC-2 criteria. RESULTS: Seventy-five (59%) FAs had a BDI score > or = 13, compared with 9 (5%) controls (odds ratio [OR] = 26.6, 95% confidence interval [CI] = 12.4 to 56.8, P < 0.001). A total of 136 (78%) controls reported their health to be good or excellent, compared with 40 (31%) FAs (OR = 7.6, 95% CI = 4.5 to 12.7, P < 0.001). Respiratory problems were present in 50 (39%) FAs and 47 (27%) controls (chi 2 = 6.992, P < 0.03). Depression rates were similar in Liverpool and Granada, although Liverpool subjects were less likely to report good health. On logistic regression, BDI status was the major predictor of frequent attendance (OR = 17.18, 95% CI = 7.54 to 39.01). Self-reported ill health (OR = 2.67, 95% CI = 1.40 to 5.10) and respiratory problems (OR = 2.20, 95% CI = 1.11 to 4.37) were also associated with frequent attendance. CONCLUSION: Depressive symptoms were the major predictor of frequent attendance in this study. Clinical and research activity should therefore concentrate on the identification and management of psychological problems among FAs in general practice.

Adolescent↗
PubMed1999

The Body Attitude Test: validation of the Spanish version.

A Spanish version of the Body Attitude Test (BAT) is presented. It was validated with 165 eating disorder patients (79 anorexia nervosa, 86 bulimia nervosa) and 220 schoolgirls from the general population. Factor analysis allowed the extraction of four factors, as in the original questionnaire, but with different item loadings on each. Taken together, these four factors accounted for 67.1% of the variance. The alpha reliability coefficient was 0.92 in both groups. The test-retest reliability with a one-week interval was 0.91 in a subgroup of 34 eating disorder patients and in a subgroup of 43 girls from the general population. The difference between the mean scores of the girls from the general population and the anorexics on one hand and the bulimics on the other was highly significant (p < 0.0001). On the basis of the discriminant validity study, the use of a cut-off point of 41--which gives a sensitivity of 75.1% and a specificity of 72.7%--is recommended.

Adolescent↗
PubMed1998

Ectopic potassium uptake in trk1 trk2 mutants of Saccharomyces cerevisiae correlates with a highly hyperpolarized membrane potential.

Null trk1 trk2 mutants of Saccharomyces cerevisiae exhibit a low-affinity uptake of K+ and Rb+. We show that this low-affinity Rb+ uptake is mediated by several independent transporters, and that trk1Delta cells and especially trk1Delta trk2Delta cells are highly hyperpolarized. Differences in the membrane potentials were assessed for sensitivity to hygromycin B and by flow cytometric analyses of cellular DiOC6(3) fluorescence. On the basis of the latter analyses, it is proposed that Trk1p and Trk2p are involved in the control of the membrane potential, preventing excessive hyperpolarizations. K+ starvation and nitrogen starvation hyperpolarize both TRK1 TRK2 and trk1Delta trk2Delta cells, thus suggesting that other proteins, in addition to Trk1p and Trk2p, participate in the control of the membrane potential. The HAK1 K+ transporter from Schwanniomyces occidentalis suppresses the K+-defective transport of trk1Delta trk2Delta cells but not the high hyperpolarization, and the HKT1 K+ transporter from wheat suppresses both defects, in the presence of Na+. We discuss the mechanism involved in the control of the membrane potential by Trk1p and Trk2p and the causal relationship between the high membrane potential (negative inside) of trk1Delta trk2Delta cells and its ectopic transport of alkali cations.

Biological Transport↗
PubMed1998

Discrimination between monomorphic and polymorphic ventricular tachycardia using cycle length variability measured by wavelet transform analysis.

The objective of this study was to assess the capability of wavelet transform (WT) analysis to differentiate between monomorphic (MVTs) and polymorphic ventricular tachycardias (PVTs) in a canine model and to relate these results to epicardial isochronal maps on a beat-by-beat basis. Unipolar electrograms were simultaneously recorded from the surface of both ventricles with a 127-lead sock electrode array in 24 open-chest anesthetized dogs. The sampling frequency was 500 Hz. Atrioventricular block was induced by formaldehyde injection into the atrioventricular node. The left anterior descending coronary artery was occluded for 60 minutes under ventricular pacing (140 stimuli/min) followed by reperfusion. Ventricular tachycardias were obtained during reperfusion and during left stellate ganglion stimulation. After visual selection, a total of 97 segments of 2,048 samples (4.096 seconds) were extracted and classified as 67 MVTs and 30 PVTs. A parameter based on the cycle length variability was defined in the second scale of the WT decomposition, normalized by its mean value. Similar assessment of cycle length variability was performed based on the detection of the point of most rapid change in potential with a negative slope in excess of -0.5 mV/ms in each individual electrogram to test the accuracy of the results obtained with the WT parameter. The WT parameter correctly identified 97% MVT and 83.3% PVT segments, for an overall accuracy of 92.8%. Beat-by-beat epicardial maps of MVT displayed a cluster of sites of initial activation close to the reperfusion area, while the sites of breakthrough from beats during PVT were much more dispersed over both ventricles. A strong and significant correlation was found between the number of electrodes with the earliest epicardial activation and the WT parameter (r = .78, P < .0001). To test the accuracy of the results obtained, a comparison was performed between the WT parameter (0.082 +/- 0.007) and the cycle length variability, estimated as the normalized standard deviation of the intervals between individual electrograms (0.076 +/- 0.006). No significant differences were shown (P = .0022), and a strong linear correlation was found between both measurements (Pearson correlation coefficient, .966). It is concluded that WT analysis discriminated accurately between MVT and PVT, and a quantitative relation was found with the spatial dispersion of sites of earliest epicardial activation. The WT results strongly correlated with those obtained by another method of estimating cycle length variability. Methodologically, the strength of the WT lies in the complementary information that could be extracted from the processing of electrograms to enhance the detection/discrimination of different types of arrhythmias.

Animals↗
PubMed1998

[The postantibiotic effect of amoxicillin/clavulanic acid on Streptococcus pneumoniae strains of different serotypes and penicillin sensitivity].

Amoxicillin and clavulanic acid, combined in a 4:1 ratio, caused a significant (longer than 0.5 hours) postantibiotic effect (PAE) for the S. pneumoniae stains tested. These strains were from a different serotype (3, 6 and 9) and also had different susceptibility to penicillin. The duration of the PAE depended both on the strain and the amoxicillin/clavulanic acid concentration used. It is significant that for the serotype 9 strain, which was both penicillin and amoxicillin resistant, the duration of the PAE was between 1.5 and 2.2 hours. These results agree with those observed by other authors as to the effectiveness of amoxicillin/clavulanic acid against S.pneumoniae.

Amoxicillin-Potassium Clavulanate Combination↗
PubMed1996

Therapeutic effects of CDP-choline in Alzheimer's disease. Cognition, brain mapping, cerebrovascular hemodynamics, and immune factors.

CDP-choline was given to patients with Alzheimer's disease (AD) at a daily dose of 1000 mg/day p.o. for one month. This compound slightly improved mental performance, tended to reduce theta activity in fronto-temporal regions, increasing alpha power in occipital areas, and enhanced cerebrovascular perfusion by increasing blood flow velocity and reducing pulsatility and resistance indexes. In addition, CDP-choline diminished histamine and interleukin-1 levels in blood and serum, respectively, and increased plasma TNF.

Aged↗
PubMed1996

The capacity to transport potassium influences sodium tolerance in Saccharomyces cerevisiae.

The capacity to transport potassium and to discriminate between the different alkali cations has been found to affect sodium tolerance in Saccharomyces cerevisiae. Mutants with a defective capacity to transport K+ were more sensitive to high concentrations of Na+ because they accumulated more Na+ and less K+ than wild-type cells which showed high discrimination between K+ and Na+.

Carrier Proteins↗
PubMed1996

The effect of ovariectomy on depressed contractions to phenylephrine and KCl and increased relaxation to acetylcholine in isolated aortic rings of female compared to male rabbits.

1. Differences in vascular responses to phenylephrine, acetylcholine (ACh) and potassium chloride (KCl) were studied in rabbit aorta from female and male rabbits, in the absence and presence of an inhibitor of nitric oxide (NO) production, NG-nitro-L-arginine methyl ester (L-NAME, 100 microM). 2. Phenylephrine and KCl-induced contractions, were significantly reduced in amplitude (P < 0.01) in the rings from female rabbits compared to those from male rabbits. 3. ACh-induced relaxation was greater (P < 0.01) in aortic rings from females than from males. 4. Incubation of the rings with L-NAME abolished the phenylephrine-induced contraction differences between rings from male and female rabbits. 5. Ovariectomy eliminated the differences in vascular responses to phenylephrine, KCl and ACh of aortic rings from the female rabbits. 6. Both basal and ACh-stimulated release of nitrites from aortic rings was greater (P < 0.01) in vascular tissue from female than male rabbits. 7. These results indicate that differences in vascular reactivity in aortic rings from male and female rabbits may be associated with a higher release of NO, resulting in an increased vasodilator response in the female rabbits.

Acetylcholine↗