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C Martín

Publications and source records attributed to C Martín.

At least 37 records · Page 2Linked to original sources
PubMed2004

Legionnaires' disease clusters associated with travel to Spain during the period January 2001 to July 2003.

Epidemiological surveillance and control of travel associated cases of legionnaires' disease are necessary tasks for public health and collaboration between countries is necessary to do this. Within the framework of the European Surveillance Scheme for Travel Associated Legionnaires' Disease (EWGLINET), European Guidelines for Control and Prevention of Travel Associated Legionnaires' Disease have been produced . This has established the reporting and response criteria when cases or clusters appear. In this paper the analysis of the information corresponding to the 46 reported clusters related to Spain is presented. Data corresponds to the period January 2001 to July 2003.

Adult↗
PubMed2003

Intercalation of [Cr(C2O4)3]3 - complex in mg,al layered double hydroxides.

A Mg,Al layered double hydroxide (LDH) with [Cr(C(2)O(4))(3)](3)(-) anions in the interlayer has been synthesized following two different routes: reconstruction from a mildly calcined Mg,Al-carbonate LDH, and anion exchange from a Mg,Al-nitrate LDH. The solids prepared have been characterized by elemental chemical analysis, powder X-ray diffraction, FT-IR and UV-vis/DR (diffuse reflectance) spectroscopies, thermal methods, nitrogen adsorption at -196 degrees C, and FT-IR monitoring of pyridine adsorption. The results obtained indicate that the most appropriate method is anion exchange, leading to a well crystallized LDH with an interlayer spacing of 10 A. Due to the high pH value (>8) of the solution in the reconstruction method, however, a polyphasic system is obtained, where, in addition to a phase with the LDH structure, amorphous magnesium oxalate and chromium oxohydroxides are also formed due to hydrolysis of the complex. The interlayer complex is stable up to 200 degrees C, but the layered structure is stable up to 330 degrees C, probably because of the presence of interlayer oxalate anions formed during decomposition of the complex. Calcination leads to oxidation of Cr(3+) ions to the six-valent state, which reverts to Cr(3+) when the calcination temperature is further increased.

Journal Article↗
PubMed2003

Epidemiology of tuberculosis on Gran Canaria: a 4 year population study using traditional and molecular approaches.

BACKGROUND: In recent years several population based studies using restriction fragment length polymorphism (RFLP) analysis have shown a higher rate of recent transmission of tuberculosis than previously thought. This study was undertaken to determine the transmission patterns of tuberculosis and the potential causes of recent transmission on the island of Gran Canaria (Spain). METHODS: The strains of all patients diagnosed with tuberculosis confirmed by culture between 1 January 1993 and 31 December 1996 were typed by RFLP using the insertion sequence IS6110. A cluster was defined as two or more isolates with an identical RFLP pattern. Epidemiological linkage through contact tracing was investigated. RESULTS: Of the total of 719 patients, 153 (21.3%) were excluded because there was inadequate bacterial DNA for genotyping (n=129) or the isolates of Mycobacterium tuberculosis had less than five copies of IS6110 (n=24). The isolates from 409 patients (72.3%) were grouped into 78 different clusters with an estimated 58.5% of the cases being due to recent transmission. Young age was the only significant predictor of clustering. Only in 147 (35.9%) of the 409 patients belonging to a cluster could an epidemiological link be found. 111 patients (19.6%) were identified as having had previous contact with a tuberculosis patient and 81 of them (72.9%) belonged to a cluster. The three largest clusters included 75, 49 and 20 patients, respectively. CONCLUSION: Recent transmission is frequent among patients with tuberculosis on Gran Canaria and could be associated with certain aspects of control measures. Some of the clusters described in the study could be due to the prevalence of particular strains of M tuberculosis on the island.

Adult↗
PubMed2002

Immobilized native bacteria as a tool for bioremediation of soils and waters: implementation and modeling.

Based on 3,4-dihydroxyphenylacetate (3,4-DHPA) dioxygenase amino acid sequence and DNA sequence data for homologous genes, two different oligonucleotides were designed. These were assayed to detect 3,4-DHPA related aromatic compound-degrading bacteria in soil samples by using the FISH method. Also, amplification by PCR using a set of ERIC primers was assayed for the detection of Pseudomonas GCH1 strain, which used in the soil bioremediation process. A model was developed to understand and predict the behavior of bacteria and pollutants in a bioremediation system, taking into account fluid dynamics, molecular/cellular scale processes, and biofilm formation.

Alginates↗
PubMed2002

Artichoke cultivars (var. "Blanca de Tudela") under elevated ozone concentrations.

Ozone concentrations rise to phytotoxic levels from spring to autumn at western Mediterranean basin coastal sites, where artichoke is one of the most important crops. Simultaneously, from year to year and especially since the early 1980s, resprouting of the stumps has been decreasing in Valencian Community artichoke plantations. To see if ozone might be playing a role in this decrease, a number of plants were exposed to different levels of ozone. Results of the ozone treatments showed reduced biomass in the offshoots of plants exposed to the highest ozone treatment. The exposure to ambient ozone during the stump-establishment period, when compared to filtered-air conditions, resulted in a reduction in yield when plants were transplanted in the field under ambient ozone concentrations. And when plants were exposed to acute short picks, typical ozone visual injury appeared in the older leaves.

Agriculture↗
PubMed2002

Solid dispersions of diflunisal-PVP: polymorphic and amorphous states of the drug.

Coprecipitates of diflunisal and polyvinylpyrrolidone (PVP K15, K30, and K90) and physical mixtures were studied using x-ray diffraction analysis, infrared (IR) spectroscopy, differential scanning calorimetry (DSC), and hot-stage microscopy. X-ray diffraction results revealed an almost amorphous state, even in coprecipitates with a high content of drug, next to 70%, which was independent of the polymer molecular weight. The IR spectra of 70:30 drug-PVP solid dispersions suggest the formation of diflunisal-PVP hydrogen bonds. For 70:30 drug-polymer ratio, the physical mixture showed linear dissolution kinetics of free crystals, but the corresponding coprecipitates exhibit two different dissolution processes. When the 25:75 drug-polymer dispersion is analyzed by hot-stage microscopy, only solid plates of PVP are observed; the absence of drug particles may be due to a molecular dispersion of the drug into the polymer. Moreover, polymorphic changes of diflunisal were detected in the solid dispersions in comparison with the corresponding physical mixtures, which are always formed by polymorph II. At high concentrations of drug (75:25 and 80:20), x-ray diffraction patterns of solid dispersions showed the partial recrystallization of the drug, displaying the main diffraction peaks of polymorph I when ethanol was used as coprecipitation solvent, whereas diflunisal form IV was obtained in chloroform.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed2002

Molecular epidemiology of tuberculosis in Elche, Spain: a 7-year study.

The epidemiology of tuberculosis in Elche (Spain) was studied by restriction fragment-length polymorphism (RFLP) typing of clinical isolates of Mycobacterium tuberculosis over a 7-year period. A total of 165 isolates was typed and the clinico-epidemiological data of the patients were studied retrospectively. An overall cluster aggregation of 52.4% was found, rising to 71.43% in HIV-positive patients. There was greater aggregation in younger patients, but no statistically significant differences when other variables were analysed. The percentage of aggregation was higher than in other studies in Spain and this may be due to the longer time period of this study. The high percentage of aggregation in young patients and in thosewho were HIV-positive suggests increased recent transmission in both groups.

Adolescent↗
PubMed2001

tert-Butyl hydroperoxide-induced lipid signaling in hepatocytes: involvement of glutathione and free radicals.

tert-Butyl hydroperoxide (TBHP) mobilizes arachidonic acid (AA) from membrane phospholipids in rat hepatocytes under cytotoxic conditions, thus leading to an increase in intracellular AA, which precedes cell death. In the present work, the involvement of lipid peroxidation, thiol status, and reactive oxygen species (ROS) in the intracellular AA accumulation induced by 0.5 mM TBHP was studied in rat hepatocytes. Cells treated with TBHP maintained viability and energy status at 10 min. However, TBHP depleted GSH, as well as inducing lipid peroxidation and ROS formation, detected by dichlorofluorescein (DCF) fluorescence. TBHP also significantly increased (32.5%) the intracellular [14C]-AA from [14C]-AA-labelled hepatocytes. The phospholipase A(2) (PLA(2)) inhibitor, mepacrine, completely inhibited the [14C]-AA response. The addition of antioxidants to the cell suspensions affected the TBHP-induced lipid response differently. The [14C]-AA accumulation correlated directly with ROS and negatively with endogenous GSH. No correlation between [14C]-AA and lipid peroxidation was found. Promethazine prevented lipid peroxidation and did not affect the [14C]-AA increase. We conclude that TBHP stimulates the release of [14C]-AA from membrane phospholipids through a PLA(2)-mediated mechanism. Endogenous GSH and ROS play a major role in this effect, while lipid peroxidation-related events are unlikely to be involved. Results suggest that specific ROS generated in iron-dependent reactions, different from lipid peroxyl radicals, are involved in PLA(2) activation, this process being important in TBHP-induced hepatocyte injury.

Animals↗
PubMed2001

17beta-estradiol affects in vivo the low density lipoprotein composition, particle size, and oxidizability.

The aim of this study was to explore the possible modifications induced by 17beta-estradiol (E(2)) in vivo on low-density lipoprotein (LDL) lipid composition, particle size, and oxidizability. For this purpose, women were recruited from an in vitro fertilization program, ranging their plasma E(2) levels from less than 12 pg/ml to more than 2000 pg/ml at the end of the treatment. The LDL lipid constituents were analyzed by thin layer chromatography and image analysis, and the LDL diameter was calculated from the lipid data. The results showed that high plasma E(2) levels were associated with smaller LDL particles, with lower amounts of free and esterified cholesterol and an increased relative content of alpha-tocopherol. The hormonal treatment produced a remodelation of the LDL acyl composition, rendering a lipoprotein enriched in saturated fatty acids, with a poorer polyunsaturated fatty acid content. These alterations in the physicochemical properties of LDL paralleled changes in the susceptibility of LDL to in vitro oxidation induced by both Cu(2+) and the peroxyl radical generator, 2,2'-azobis (2-amidinopropane), these changes being mainly reflected in a reduced maximum oxidation rate. The in vivo changes in the physicochemical properties of LDL induced by E(2) could explain some of the antiatherogenic actions of estrogens.

Adult↗
PubMed2001

Influence of diuretics on the concentration of proteins and other components of pleural transudates in patients with heart failure.

PURPOSE: Diuretic therapy increases the total protein and lactate dehydrogenase concentrations in pleural fluid in patients with transudates due to heart failure, but the effect of diuresis on other substances in pleural fluid constituents is not known. SUBJECTS AND METHODS: Twenty-one patients with transudative pleural effusions due to congestive heart failure were prospectively studied. Repeated diagnostic thoracentesis (mean +/- SD = 3 +/- 1; range, 2 to 6) was performed until the effusions were radiographically unapparent (5 +/- 2 days). Thirty-one patients with congestive heart failure who underwent only a single thoracentesis after diuretic therapy served as controls. We measured the concentrations of various components of pleural effusions in the serum and in the pleural fluid, and determined the serum-pleural fluid gradient (serum concentration minus pleural fluid concentration) and ratio (serum concentration divided by pleural fluid concentration). RESULTS: The pleural concentrations of most components increased significantly (P <0.001) from the initial specimen to the final specimen: total protein, from 23 +/- 7 g/L to 33 +/- 9 g/L; albumin, from 13 +/- 4 g/L to 18 +/- 6 g/L; lactate dehydrogenase, from 177 +/- 62 U/L to 288 +/- 90 U/L; cholesterol, from 31 +/- 16 mg/dL to 52 +/- 22 mg/dL; and cholinesterase, from 1,304 +/- 616 U/L to 1,884 +/- 674 U/L. Expressed as percentage change, the increases in the serum-pleural fluid gradients for albumin (12% +/- 22%) and total protein (11% +/- 12%) were significantly less than the increases in their concentrations in pleural fluid (albumin, 47% +/- 49%; total protein, 48% +/- 40%) or in their pleural fluid/serum ratios (albumin, 27% +/- 29%; total protein, 38% +/- 34%). CONCLUSIONS: The concentrations of the biochemical components commonly measured in pleural fluid increase progressively during diuretic therapy. Calculation of the serum-pleural fluid gradients for protein and albumin may be the most useful way to distinguish transudates from exudates in patients with congestive heart failure who have undergone diuresis.

Aged↗