PubMed Health⌕ Search

Biomedical subjects

P Catalán

Publications and source records attributed to P Catalán.

At least 19 recordsLinked to original sources
PubMed2005

On the verge of extinction: genetics of the critically endangered Iberian plant species, Borderea chouardii (Dioscoreaceae) and implications for conservation management.

Borderea chouardii is a relictual and dioecious, strictly sexually reproducing, long-living geophyte of the Dioscoreaceae family. Previous biological and demographic studies have indicated the existence of a uniformly distributed panmictic population of this taxon at the southernmost Spanish pre-Pyrenean mountain ranges where it occurs in rather inaccessible crevices of a single limestone cliff. However, individuals of B. chouardii are spatially subdivided into two subpopulations located, respectively, on the upper and lower parts of the cliff, and vertically separated 150 m. Because of its extreme rarity, B. chouardii was the first Iberian taxon to have a specific conservation plan and has been included in several red lists under the category of critically endangered (CR). However, no previous attempts have been conducted to analyse the fine scale evolutionary mechanisms involved in its present microspatial distribution. Genetic diversity and population structure have been investigated through the analysis of neutral hypervariable markers such as simple sequence repeats (SSRs) and randomly amplified polymorphic DNAs (RAPDs) to unravel the impact of life history traits in the differentiation of the two subpopulations. Both types of molecular markers were unequivocal in distinguishing two genetically distinct groups of individuals corresponding to their spatial separation. However, SSRs detected a higher level of subpopulation differentiation (F(ST) = 0.35, R(ST) = 0.32) than RAPDs (F(ST) = 0.21). SSR data indicated significant deviation from random dispersal of genes and genotypes between the two groups, suggesting that mating occurs mainly among individuals within subpopulations, thus, favouring the divergence between the two groups. This microevolutionary differentiation scenario might have been caused by a coupled effect of past genetic drift and reproductive isolation, as a result of strong glacial age bottlenecks and inefficient dispersal system of pollen and seeds, respectively. The identification of such genetic structure in this narrow endemic prompts a modification of the management strategies of its single extant population.

Conservation of Natural Resources↗
PubMed2001

[Yield of transthoracic echocardiography with high frequency transducer in the study of the anterior descending coronary artery].

INTRODUCTION AND OBJECTIVES: This study was performed to evaluate the feasibility and utility of a transthoracic high frequency transducer to detect and measure the left anterior descending coronary artery flow in patients with lesions in this artery or anterior myocardial infarction. MATERIALS AND METHODS: We studied 11 subjects with lesions greater than 75% and another 10 with anterior myocardial infarction. We compared the results with a control group of 18 subjects. An ATL HDI 5000 ultrasound unit with a 5-8 MHz transducer was used to identify the left anterior descending in the anterior interventricular sulcus from an apical four chamber window. We considered that left anterior descending was detected when a diastolic predominant flow pattern was obtained with pulse Doppler. RESULTS: Left anterior descending was detected in 37/39 of cases (94.4%). Patients with coronary lesions showed a decrease in the limit of significance in the diastolic/systolic peak velocity ratios: 2.5 (SD 0.7) vs 1.8 (SD 0.3) with a p = 0.024. Patients with anterior myocardial infarction obtained lower diastolic/systolic peak velocity ratios than controls: 2.5 (SD 0.7) vs 1.4 (SD 0.3) with a p = 0.001. CONCLUSIONS: Left anterior descending coronary artery flow can be assessed by transthoracic high frequency echocardiography in greater than 90% of the cases. Patients with coronary lesions and those with anterior myocardial infarction have a decreased diastolic/systolic peak velocity ratio.

Aged↗
PubMed2001

"Second-look" cytotoxicity: an evaluation of culture plus cytotoxin assay of Clostridium difficile isolates in the laboratory diagnosis of CDAD.

Clostridium difficile is one of the most frequent causes of hospital-acquired diarrhoea. Our objective was to prove that some stool samples with a direct negative cytotoxicity assay may indeed harbour toxigenic C. difficile and that this can be demonstrated by performing a "second-look" cytotoxicity assay using the isolated C. difficile strains. Over an eight-year period (1992-1999), the 8241 stool samples submitted for direct cell culture from patients with suspected C. difficile-associated diarrhoea (CDAD) were simultaneously plated on cycloserine cefoxitin fructose agar. C. difficile strains isolated from samples with a negative direct cell culture assay were re-tested for toxin production "second-look" cell culture assay). Using both methods 6423 samples (78%) were negative. Of the remaining 1818 samples, 127 (7%) yielded C. difficile isolates which were confirmed as non-producers of toxin by both methods, 1437 (85%) were positive in direct cell culture assay, and 254 were positive only after the "second-look" cell culture assay. Thus, our approach allowed us to detect an extra 15% of toxin-producing strains that could have gone undetected otherwise.The combination of direct-cell culture assay, culture for toxigenic C. difficile and "second-look" cell culture assay enhances the potential for diagnosis of CDAD and enables us to be more efficient with our patient care resources.

Bacterial Toxins↗
PubMed2000

[Left ventricular pseudoaneurysm with a fistula to right ventricle following previous repair of septal defect after acute myocardial infarction].

A case of left ventricular pseudoaneurysm with a fistula to right ventricle is presented. It appeared following the repair of a ventricular septal defect after acute myocardial infarction. The left ventricular pseudoaneurysm is associated, in most cases, with acute myocardial infarction. However, we should not forget surgery as aetiology of this pathology. The most frequent post-surgery pseudoaneurysms appear after aneurysmectomy and after mitral valve replacement. They tend to develop fistulas which differ from post acute myocardial infarction pseudoaneurysms. Few cases have been described following the repair of septal defect and none of them complicated with a fistula to right ventricle, as in our case.

Aneurysm, False↗
PubMed1999

Differences in curable STDs between HIV and non-HIV populations in Spain.

The pandemic impact of HIV has changed the clinical spectrum of STDs all over the world. The incidence and frequency of STDs in the different global geographic areas demonstrate the diagnostic and treatment capabilities of various local and national health systems and is simultaneously informing about the sexual behaviours of the population. The purpose of this study was to determine the frequency of curable STDs (herpes, chlamydia, gonorrhoea, syphilis, trichomoniasis) in a hospital-based STD clinic in Madrid, Spain during a 4-year period. Patients were referred mainly from the emergency department, gynecological wards, and family planning (61%) as well as from the HIV-hospital unit (31 beds) and outpatient department (39%). The total number of patients seen was 952 (243 men, 709 women) with an annual average of 238 patients per year. Of these, 139 (14.6%) were HIV-patients and 813 (85.4%) non-HIV patients. In non-HIV patients, STDs were identified in 493 cases (54.2%). In HIV-patients, STDs were diagnosed in 108 cases (77.7%; p < or = 0.001). Two or more STDs were more prevalent in HIV than non-HIV patients. The frequency of STDs in both HIV and non-HIV patients were vulvovaginal candidiasis, 47.8%:57.2%; syphilis, 11.7%:1.4% (p < or = 0.05); gonorrhea, 5.3%:3.9%; Gardnerella vaginosis, 6.3%:4.8%; genital chlamydia, 6.3%:9.06%; trichomoniasis, 17%:6.5% (p < or = 0.05); and genital herpes, 20.2%:5.3% (p < or = 0.05).

Adolescent↗
PubMed1999

Cytopathic effect inhibition assay for determining the in-vitro susceptibility of herpes simplex virus to antiviral agents.

We compare a rapid dilution method for the determination of antiviral susceptibility of herpes simplex virus (HSV) with the plaque reduction assay. A total of 84 HSV clinical isolates were studied by both methods to detect in-vitro resistance to acyclovir and foscarnet. The rapid method showed for the detection of HSV isolates resistant to acyclovir and foscarnet, a sensitivity of 96. 8% and 100% and specificity of 100% and 100%, respectively. This method provides an easy and accurate screening procedure for the susceptibility testing of HSV to antiviral agents.

Acyclovir↗
PubMed1997

Phylogeny of Poaceae subfamily Pooideae based on chloroplast ndhF gene sequences.

Forty-eight representatives of 12 tribes attributed to the subfamily Pooideae s.l. of grasses (Monocots) have been studied by sequencing the more variable 3' end of the chloroplast ndhF gene. Six representatives from 5 different tribes of Poaceae (Oryzeae, Streptogyneae, Bambuseae, Arundineae, Phareae) and from Joinvilleaceae were used as outgroups. Phylogenetic analyses of the data render a monophyletic Pooideae clade and provide an evolutionary hypothesis for all its tribes (Poeae, Aveneae, Bromeae, Triticeae, Brachypodieae, Meliceae, Stipeae, Lygeae, Nardeae, Diarrheneae, Brachyelytreae, Phaenospermatae). The subfamily is composed of two subsets of tribes, a basal group that includes six old lineages or satellite tribes, in which Brachyelytreae is the first diverging branch followed by the Lygeae/Nardeae clade, and a group of six more recently evolved tribes (Pooideae s.s.), in which the divergence of Diarrheneae antedates that of Brachypodieae, sister group to the "core pooids." The character changes found within the sequenced nucleotide positions of the ndhF gene also have proven to be informative at lower hierarchical levels (genus and species) for some tribes.

Base Sequence↗
PubMed1997

Group A streptococcal bacteremia. A 10-year prospective study.

In this paper we present a prospective evaluation of 100 patients with Group A Streptococcal (GAS) bacteremia evaluated in our hospital over a 10-year period. Sixty-two patients were intravenous drug users (IVDU); all but 1 of these had an obvious cutaneous portal of entry related to the injection of illicit drugs. Twenty-seven patients had infectious metastasis, and the presence of septic pulmonary embolism was associated with suppurative phlebitis. Four of these patients had endocarditis. In the non-IVDU group, 24 patients had an underlying disease, and 12 were immunosuppressed. In 14 cases the infection was of hospital acquisition; in 35% infection was related to medical manipulations. Comparing the IVDU and non-IVDU groups, GAS bacteremia in IVDU patients is associated with a more benign outcome, a longer time of evolution before diagnosis, and a lower frequency of septic shock and mortality than in non-IVDU patients. Although in the univariate analysis GAS bacteremia was associated with several variables, in the multivariate analysis only the presence of shock and nosocomial acquisition of the infection were independently associated with a fatal outcome. Fifty-two patients were infected with human immunodeficiency virus (HIV); 5 of these were in the non-IVDU group. During the last 5 years of study, GAS bacteremia in our hospital was 39 times more frequent in HIV-infected patients than in patients without HIV. Nine patients presented clinical criteria corresponding to Streptococcal toxic shock syndrome (STSS), although its incidence was lower in the IVDU group. In the non-IVDU group, STSS was more frequent in patients with a necrotizing portal of entry, an age between 20 and 40 years, women, and when the origin of the infection was the skin or soft tissue. Six patients with STSS died, and death was associated with the presence of necrotizing lesions and lower counts of white cells, platelets, or hemoglobin.

Adolescent↗
PubMed1996

Emergence of teicoplanin-resistant coagulase-negative staphylococci.

Over a period of 5 years we have recovered 32 clinical isolates of coagulase-negative staphylococci (CoNS) exhibiting either decreased levels of susceptibility or true resistance to teicoplanin (MICs, 16 to 128 micrograms/ml); these isolates make up 0.55% of the total CoNS isolated by us. Twenty-nine of the strains were also methicillin resistant, and all were susceptible to vancomycin. Fourteen of the strains were Staphylococcus epidermidis, fourteen were Staphylococcus haemolyticus, and four were Staphylococcus hominis. In one case, a strain of S. haemolyticus was isolated with a vancomycin-resistant, teicoplanin-resistant Enterococcus faecalis strain. All strains were nosocomially acquired and were isolated from 17 different wards. Teicoplanin resistance occurred as a sporadic phenomenon, and none of the isolates were epidemiologically related. The isolates were from 30 patients, 13 of whom presented with true infections (43%). Five (38%) of the 13 patients with true infections had been previously treated with vancomycin. None of the infected patients were previously treated with teicoplanin. The in vivo development of resistance to teicoplanin among CoNS strains limits the therapy of infections by these microorganisms. There is a need for surveillance of nosocomial isolates of CoNS to determine resistance to glycopeptides.

Aged↗
PubMed1996

[Diarrhea associated with Clostridium difficile: one-year experience in a general hospital].

Clostridium difficile is considered the most common cause of nosocomial acquired diarrhoea, with frequencies differing widely from one institution to another. So far, it is a scarcely reported condition in Spain. In the present study 129 episodes of Clostridium difficile associated diarrhoea (CDAD) occurred in 120 patients in a 2,000-bed hospital in 1994 is reported. All cases were diagnosed by demonstrating cytotoxicity on cellular lines (MRC-5) from feces or from the strain isolated from a culture medium (CCFA). The overall incidence was 2.4 episodes every 1,000 admissions. Twenty-eight out of the 120 patients (23%) were HIV-positive patients, that is, an incidence of 30 episodes every 1,000 admissions. No significant differences were observed regarding the presentation and clinical course between HIV-positive and HIV-negative patients, with the exception of the antimicrobial agents used previously. Forty-two percent of patients had undergone surgery and 97% had received antimicrobials in the 8 weeks before the CDAD episode, with an average of 3.3 antibiotics per patient. Out of the 129 episodes, 72.8% were treated correctly. A total of 11.7% of patients responded exclusively to the discontinuation of the antimicrobials that were being administered. Eighty-three patients were treated with specific antibiotics, 59 with oral vancomycin, and 24 with metronidazole. Seventy-six patients (91.5%) responded to the initial therapy, 5 relapsed (6%), and 2 (2.5%) failed. The associated mortality rate was 0.7%. C. difficile can be a relevant cause of nosocomial diarrhoea in our setting, particularly in HIV-positive patients, but also in other patients. Its early diagnosis and appropriate therapy can contribute to decrease a relevant cause of morbidity in inpatients.

Anti-Bacterial Agents↗
PubMed1991

[Alterations in calcium metabolism in patients with active tuberculosis].

BACKGROUND: Abnormalities in phosphocalcic and vitamin D metabolism may develop in patients with active tuberculosis (TB). Their incidence and relationship with the disease is not well known, particularly in our area. We have prospectively evaluated 40 patients with TB [(30 with localized TB (LTB) and 10 with disseminated TB (DTB)]. METHODS: After stabilizing the diet during 4 days, the calcium, phosphorus, magnesium and creatinine balances, blood ionic calcium, plasma intact PTH, 25-hydroxy vitamin D [25(OH)D] and serum 1.25 dihydroxyvitamin D [1.25(OH)2D] were measured. RESULTS: Hypercalcemia was not found in any patient, but 25% had hypercalciuria (HC). The 24-hour urinary excretion of calcium was higher in patients than in controls (3.2 +/- 1.7 mg/kg or 0.10 +/- 0.06 mg/100 ml of GFR vs 2.3 +/- 0.7 mg/kg or 0.08 +/- 0.03 mg/100 ml of GFR, p less than 0.05), basically at the expense of patients with DTB (4.4 +/- 1.8 mg/kg or 0.14 +/- 0.06 mg/10 ml of GFR, p less than 0.005). These had a lower PTH than patients with LTB and controls (12.8 +/- 7.7 vs 18.5 +/- 6.9 vs 19.5 +/- 6.0 pg/ml, p less than 0.05). Independently from the extent of the disease, the patients with HC had a lower PTH (12.6 +/- 6.8 vs 18.5 +/- 6.9 pg/ml, p less than 0.01) and higher serum 1.25(OH)2D (34.5 +/- 10.1 vs 25.0 +/- 7.2 pg/ml, p less than 0.01) than patients without HC. The levels of 25(OH)D were lower in patients with TB than in controls (11.2 +/- 6.0 vs 20.0 +/- 7.0 ng/ml, p less than 0.05), independently from the extent of the disease and the presence or absence of HC. CONCLUSIONS: Patients with tuberculosis may have hypercalcinuria with inadequately high levels of 1.25(OH)2D and low intact PTH. This abnormality appears to be correlated with the extent of the disease.

Adult↗
PubMed1991

25(OH)D levels in diabetic pregnancies relation with neonatal hypocalcemia.

The levels of 25(OH)D have been quantified in 42 insulin diabetic pregnancies (DP) through the three trimesters of pregnancy with a total of 177 determinations. In parallel we quantified this metabolite in 114 normal pregnant women (NP) and also in 116 normal controls (NC). In addition 25(OH)D was quantified in 18 (DP) and 19 (NP) at delivery in the 35-37th week of pregnancy, and ionic calcium was measured in their newborns at 24 h of life. Grouping by trimesters of gestation, the (NP) group had 25(OH)D levels similar to those of (NC) and none showed significant differences between trimesters of pregnancy. (DP) showed in all seasons lower (25(OH)D levels than (NC) but did not have differences in these levels between trimesters of pregnancy. The newborns of (DP) had lower ionic calcium levels than newborns of (NP). Eight newborns of (DP) had hypocalcemia and seven of their mothers showed 25(OH)D levels lower than 10 ng/ml. These findings suggest that lower 25(OH)D levels in (DP) can influence the neonatal hypocalcemia in their newborns.

Adult↗
PubMed1991

[Evaluation of 5 selection criteria for sputum as a valid sample for culture].

We compare five selection criteria to discriminate between good quality expectorated sputum and specimens contaminated with upper respiratory tract secretions. We employed two microscopic methods (Bartlett, Heineman) which rely upon the number of squamo-epithelial cells and polymorphonuclear leucocytes; and a macroscopic method (the Medical Research Council) which evaluates the gross appearance of sputum, with three different criteria for admission established by our own. Three hundred and thirty two sputum were included. We evaluated sensitivity, specificity and predictive values as compared with isolation or not of a potential pathogen. We obtained 72% and 45% sensitivity, and 81% and 86% specificity for Bartlett and Heineman methods respectively. Most restrictive criterion for macroscopic method provided 57% sensitivity and 82% specificity; least restrictive showed 97% sensitivity and 17% specificity. Macroscopic method is a quick, valuable screening for discarding sputum contaminated with upper respiratory tract secretions.

Bacteria↗
PubMed1988

[Parathyroid hormone: perinatal aspects].

Authors have measured parathormone levels in 28 mothers at delivery and their respective newborns at 40-50 hours after birth. They also quantified these levels in umbilical vessels. Control groups was formed by 48 healthy non pregnant women. PTH levels in pregnant women were similar to controls. In umbilical artery these values were higher than in umbilical vein and in both, lower than other groups. Newborns at 40-50 hours after birth showed higher PTH levels than controls and pregnant women at delivery. A positive correlation between the PTH levels of the mother and those of the umbilical vessels is found. PTH levels of the neonate at 40-50 hours after birth correlated with levels of umbilical artery and umbilical vein. They do not observe a hyperparathyroidism at the delivery, although there is a slight decrease in Ca levels. Newborns at 40-50 hours after birth did show an increase in their PTH levels in parallel with hypocalcemia correlation found between PTH levels of the mother and those of the umbilical vessels could suggest a placental transfer for this hormone.

Calcium↗
PubMed1987

[Levels of 25-hydroxycholecalciferol in human serum in all ages: seasonal differences].

The 25-hydroxycholecalciferol (25-HCC) levels have been quantified in 172 normal controls. Three groups were considered: children (0-12 years), younger than 50 year-old adults and older than 50 year-old adults. In order to evaluate the seasonal variations in this metabolite their levels throughout the year were quantified. A negative correlationship was observed between age and 25-HCC levels. Grouping the levels according to maximum and minimum solar irradiation, the children's group showed higher values than the other groups in both seasons, while younger group (under 50 years of age) showed higher levels than the older group only in maximum solar irradiation. The children's and younger people's groups showed significant differences in the 25-HCC levels between the period of maximum and minimum solar irradiation which did not occur in the older group. In our geographic area, age and seasons of the year are factors that may influence 25-HCC levels. Therefore knowledge of these factors is basic for understanding correctly these metabolite levels.

Adult↗
PubMed1987

[Changes in serum and urinary levels of phosphorus in pregnant women, induced by effect of milk supplementation].

It was studied the levels of phosphorus in serum and urine in two groups of pregnant women. One group was advised to follow their usual intake and the other to supplement the diet with 750 ml of milk. A control group of healthy non pregnant women were conformed to the same protocol. Pregnant women that followed their usual intake had the same levels of serum phosphorus and maximum phosphate transport as controls. Pregnant women who had taken milk supplement showed in the second and third trimester of pregnancy significantly lower serum phosphorus and maximum phosphate transport levels than controls and also with respect to pregnant women in the first trimester. It suggests a possible influence of diet on these parameters. Both groups of pregnant women showed hyperphosphaturia through the three trimesters.

Adult↗