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Biomedical subjects

L de la Fuente

Publications and source records attributed to L de la Fuente.

At least 19 recordsLinked to original sources

Rapid growth of cartilage rudiments may generate perichondrial structures by mechanical induction.

Experimental and theoretical research suggest that mechanical stimuli may play a role in morphogenesis. We investigated whether theoretically predicted patterns of stress and strain generated during the growth of a skeletal condensation are similar to in vivo expression patterns of chondrogenic and osteogenic genes. The analysis showed that predicted patterns of compressive hydrostatic stress (pressure) correspond to the expression patterns of chondrogenic genes, and predicted patterns of tensile strain correspond to the expression patterns of osteogenic genes. Furthermore, the results of iterative application of the analysis suggest that stresses and strains generated by the growing condensation could promote the formation and refinement of stiff tissue surrounding the condensation, a prediction that is in agreement with an observed increase in collagen bundling surrounding the cartilage condensation, as indicated by picro-sirius red staining. These results are consistent with mechanical stimuli playing an inductive or maintenance role in the developing cartilage and associated perichondrium and bone collar. This theoretical analysis provides insight into the potential importance of mechanical stimuli during the growth of skeletogenic condensations.

Animals↗

Evaluating the impact of methadone maintenance programmes on mortality due to overdose and aids in a cohort of heroin users in Spain.

AIMS: To assess the relationship between methadone treatment (MT) and overdose and HIV/AIDS mortality among heroin users resident in Barcelona city. DESIGN: All patients who started treatment in any treatment centre between 1992 and 1997 were included in a cohort the first time they were admitted for heroin addiction treatment. Follow-up controls were carried out every 9 months, on average, until 31 December 1999. Variables, both constant and varying over time, were fitted into Cox regression models. FINDINGS: The study recruited 5049 patients, which provided 23,048.2 person-years. Fifty per cent were in MT during the study period; of the total cohort 1005 patients died: 38.4% due to AIDS, 34.7% to overdose and 27% to other causes. Overall mortality decreased from 5.9 deaths per 100 person-years in 1992 to 1.6 in 1999. Globally, life expectancy at birth was 39 years, 38 years lower than that of the general population. The main factor for overdose mortality was not being in MT at the time of death [relative ratio (RR) = 7.1]; other factors were being a current injector at baseline and being HIV positive. For AIDS mortality, the main factor was the calendar year (RR for 1996 versus 1999 = 4.6), the next major factor was more than 10 years of heroin consumption, followed by not being in MT, being unemployed, then having a prison record. CONCLUSIONS: The observed mortality decline could be linked to the effectiveness of low-threshold MT. The life expectancy of heroin users increased by 21 years during the study period.

Acquired Immunodeficiency Syndrome↗

Altered dose-to-effect of propofol due to pharmacokinetics in rats with experimental diabetes mellitus.

Pathology related alterations in the pharmacokinetics or the pharmacodynamics of propofol could contribute to the observed large variability in the hypnotic dose. We have tested the influence of diabetes mellitus on the induction dose and the pharmacokinetics and pharmacodynamics of propofol in rats. Diabetes was induced in rats by administration of streptozotocin (60 mg kg(-1), i. p.) while control rats received vehicle intraperitoneally. All animals had glucose, cholesterol, triglycerides and albumin levels measured. In-vitro protein binding was determined by ultrafiltration. Rats were randomly split into set 1 (dose-concentration-effect study) with control and streptozotocin rats, and set 2 (pharmacokinetic study), with control and streptozotocin rats. Rats in the effect set received either a variable infusion of 6 mg kg(-1) min(-1) propofol until onset (induction dose) of the hypnotic effect (loss of the righting reflex), or a 15 mg kg(-1) bolus to assess offset time (recovery of the righting reflex). Blood (C(blood)) and brain (C(brain)) propofol concentrations at onset and offset were assayed by HPLC. In the pharmacokinetic study, propofol was administered intravenously at 6 mg kg(-1) min(-1) for 2 min. Arterial blood samples were collected between 0.5 and 540 min and assayed for propofol. A mixed effects compartmental pharmacokinetic modelling method (NONMEM) was used to analyse the observations and variabilities. The dose necessary for onset differed between streptozotocin and controls, and so did the pharmacokinetics with two- and three-compartment descriptions, respectively. C(blood) and C(brain) at onset and offset were similar, possibly rejecting changes in pharmacodynamics. The total and unbound volume of distribution was significantly lower in the streptozotocin group with no differences in clearance (CL) between streptozotocin and controls, (mean (inter-animal CV%)) CL = 0.026 (17%) and 0.025 (62%) L min(-1), respectively. Individual Bayes Vd(ss) (volume of distribution at steady state) were different, (mean (s. d.)) Vd(ss) = 7.7 (2.67) and 1.11 (0.09) L, respectively. The pharmacokinetic model was validated by comparison with the data from set 1. Simulations of total and unbound C(blood), for both groups, at the hypnotic dose for the controls, revealed differences throughout the time course of the pharmacokinetics. The difference observed in the induction dose of propofol to streptozotocin and control rats was due to alterations in the pharmacokinetics, secondary to the pathology.

Anesthetics, Intravenous↗

Development of a multilocus sequence typing method for analysis of Listeria monocytogenes clones.

This study is a first step in the development of multilocus sequence typing (MLST) method for Listeria monocytogenes. Nine housekeeping genes were analyzed in a set of 62 strains isolated from different sources and geographic locations in Spain. These strains were previously characterized by pulsed-field gel electrophoresis (PFGE). Because of low diversity, two loci were discarded from the study. The sequence analysis of the seven remaining genes showed 29 different allelic combinations, with 22 of them represented by only one strain. The results of this sequence analysis were generally consistent with those of PFGE. Because MLST allows the easy comparison and exchange of results obtained in different laboratories, the future application of this new molecular method could be a useful tool for the listeriosis surveillance systems that will allow the identification and distribution of analysis of L. monocytogenes clones in the environment.

Alleles↗

[Clinical and functional analysis of long-term results of uvulopalatopharyngoplasty].

In order to evaluate the clinical and functional effectiveness of uvulopalatopharyngoplasty (UPPP) in chronic roncopathy, we studied the subjective improvement of operated patients and compared to pulsioximetry findings before and after surgery. A follow-up was made on 72 patients entitled of chronic roncopathy--51 with obstructive sleep apnea syndrome (OSAS) and 21 with simple snoring-, for a mean period of time of 41 months. Preoperatory study included on ENT exploration, fibre optic endoscopy, Müller maneuver, pharyngeal CT, value of daytime sleepiness with Epworth's scale, espirometry and pulsioximetry, and the postoperatory study included of pulsioximetry and a health questionnaire over snoring and daytime sleepiness. Snoring improved or disappeared in 13 of 21 patients (61.8%), and daytime sleepiness did it in 26 of 39 (66.6%). Therapeutic failure in snoring was mainly due to an increase in the body mass index. After UPPP in OSAS, only 21 patients (41.1%) showed all positive response criteria (decrease into ODI > or = 50% or in absolute values < 6, CT 90% < 1%, and SaO2 Min > or = 85%). UPPP failed in long term evaluation in the rest of individuals. Patient selection is mandatory to optimize clinical response of UPPP for snoring, without OSAS success depends on body mass index, respiratory disturbances ratios and the eventual presence of another upper airways collapses below velopharyngeal segment.

Adult↗

Sociodemographic characteristics and HIV risk behaviour patterns of male sex workers in Madrid, Spain.

This paper describes the sociodemographic and work characteristics, prevalence of HIV infection and associated risk behaviours among male sex workers (MSWs) in Madrid (Spain). Using an anonymous semi-structured questionnaire, educators attached to a mobile unit under a street-based prostitution programme surveyed 84 MSWs from several Madrid areas. Of the total surveyed: 35% were immigrants, mean age was 23 years, mean period in prostitution was four years; 21% had no primary education; 16% had injected drugs at some time; 11% reported private sexual relationships exclusively with women; 89% always used condoms in anal practices with clients; and 41% were in sexual relationships with their partners. Only 11% had ever used fortified condoms. In the preceding month, 37% had experienced condom failure, 82% without having used any lubricant. In all, 67% reported having undergone HIV testing, with a higher percentage of positive results among injecting (60%) versus non-injecting drug users (17%). Immigrants had a lower level of education, made less use of condoms, had more condom failures and, in their private lives, a greater proportion reported sexual relationships exclusively with women. In Spain, MSWs should be included in HIV prevention programmes, which ought to be specifically adapted to immigrants. Priority should be given to reducing the condom failure rate in anal intercourse, by improving access to fortified condoms.

Adolescent↗

[Trends in the number of human immunodeficiency virus infected persons and AIDS cases in Spain: 1980-1998].

BACKGROUND: To describe the trend in the number of HIV-infected persons and the number of AIDS cases in Spain between 1980 and 1998. SUBJECTS AND METHODS: The following information was used: annual incidence of AIDS taken from the National Registry, AIDS deaths taken from the same registry and from the Registry of Vital Statistics, HIV seroprevalence in studies in sentinel populations, HIV incidence in cohorts of exposed persons, and reports of HIV infections in the registries existing in the autonomous communities. We considered three events of interest--HIV infection, AIDS and death--which were related using back-projection and compartmental models. RESULTS: HIV spread rapidly in Spain during the years 1980. Transmission subsequently declined by more than 50% to figures that probably do not exceed 6,000 new infections in 1998. The incidence of AIDS increased to more than 7,000 new cases in 1994 and has since declined to some 4,000 cases in 1998. The level of AIDS mortality has always been lower than the incidence; it increased up to 1995 and then dropped to less than half in subsequent years. The number of living persons infected with HIV, including AIDS cases, arose until the early years 1990 and has since remained steady at about 125,000 persons. The number of cases of living persons with AIDS has increased continuously, and is estimated at about 19,000 through the end of 1998. CONCLUSIONS: The recent trend in new infections, AIDS cases and deaths is favourable, while the number of infected living persons remains very high.

Acquired Immunodeficiency Syndrome↗

In vitro susceptibilities of 400 Spanish isolates of Neisseria gonorrhoeae to gemifloxacin and 11 other antimicrobial agents.

The in vitro activity of gemifloxacin versus those of 11 other antimicrobial agents against 400 strains of Neisseria gonorrhoeae was determined by microdilution with supplemented GC agar. A total of 37.5% of the strains were beta-lactamase positive. A total of 70 and 6.4% of the beta-lactamase-negative strains exhibited intermediate and high-level penicillin resistance, respectively. Ceftriaxone and gemifloxacin were the most active drugs (MICs at which 90% of isolates are inhibited, 0.01 versus 0.007 microg/ml, respectively), with 100% of strains inhibited by 0.12 microg/ml.

Anti-Bacterial Agents↗

[Susceptibility to antimicrobial drugs used in the prophylaxis of meningococcal disease: situation after an epidemic wave].

In the early 1990s a rise in the incidence of meningococcal disease was observed in Galicia, Spain, most cases of which were caused by serogroup C meningococcal strains. As part of the epidemiological analysis of this epidemic wave, two studies of asymptomatic carriers of neisseria meningitidis were carried out: the first took place during the period of maximum incidence and coincided with a massive immunization campaign (December 1996 to January 1997); and the second was conducted one year later (January 1998). A total of 1234 meningococcal strains were isolated in both studies (789 in the first and 445 in the second study) and the susceptibility to rifampin, ciprofloxacin, ceftriaxone and sulfadiazine was determined. The susceptibility to rifampin, ciprofloxacin and cetriaxone was high among the strains isolated in both studies. For sulfadiazine, the percentage of resistant strains was 92.6% for the first and 86.3% for the second study.

Adolescent↗

[The prevalence of human immunodeficiency virus infection and the risk behaviors in the heroin addicts of Barcelona, Madrid and Seville: an example of the advantages of centering studies on addicts and not just on intravenous users].

BACKGROUND: The switch from intravenous heroin administration to smoking of heroin might be changed the trends in the prevalence of HIV infection and risk behaviours among Spanish users. SUBJECTS AND METHODS: Cross-sectional study of 909 regular heroin users, recruited within and outside of drug treatment centres. The prevalence of HIV infection and risk behaviours were studied in the whole sample and among injectors. RESULTS: The proportion of heroin users who had ever injected was 86.7% in Barcelona, 71.1% in Madrid and 56.1% in Seville, while the proportion of those who had injected in the last 30 days was 79.7, 35.6 and 29.2%, respectively. The prevalence of HIV infection among users who had ever injected was 46.2% in Barcelona, 39.6% in Madrid and 47.1% in Seville; in the total population of heroin users the prevalence was 40, 31.1 and 28%, respectively. Among current injectors, 10.9% in Barcelona, 13.9% in Madrid and 23.6% in Seville reported they had injected with used syringes in the last 30 days, while the corresponding proportion among the total population of users was 8.7, 4.9 and 6.9%, respectively. Moreover, 19.2% of injectors in Barcelona, 16.7% in Madrid and 16.9% in Seville admitted to injecting drugs which had been diluted in syringes previously used by others in the last 30 days; of this group, over half stated they had not injected with used syringes during that period. CONCLUSIONS: The prevalence of HIV infection and risk behaviours among heroin users differs depending on whether all users or only injectors are considered. This suggests that the transition from injecting to smoking is one of the major factors contributing to the control of the HIV epidemic in Spain. This contribution, which has little to do with regional prevention policies, must be taken into account when comparing their effectiveness.

Adult↗

Drug and alcohol consumption and sexual risk behaviour among young adults: results from a national survey.

To study the association of the consumption of alcohol and other psychoactive drugs with sexual risk behaviour for HIV infection, data from a representative sample of the Spanish population aged 18-39 years were analysed. A national household survey was carried out in 1996 using a combination of face-to-face interviews and self-administered questionnaires. The survey included 5253 subjects aged 18-39 years who provided information on alcohol and drug consumption, number of sexual partners and condom use with the steady partner and with casual partners in the 12 months before the survey. Of those surveyed, 27.4% had been drunk at least once and 20.5% had consumed drugs. Both behaviours were associated with male sex, younger age, higher educational level, being single and having had more than one sexual partner. In the logistic regression analysis adjusting for the sociodemographic variables, the greater frequency of drunkenness and cannabis use were associated with having more than one sexual partner. Regular condom use was significantly less frequent among cocaine users and more frequent among opiate users, but was not associated with the use of other drugs. Sexual risk behaviour (i.e. more than one partner and failure to use a condom regularly) was more frequent among persons who had been drunk or used cannabis or cocaine. Excessive consumption of alcohol, and cannabis and cocaine use are independently associated with sexual behaviour involving greater risk of HIV infection or transmission.

Adolescent↗

[Acute respiratory problems and cocaine or heroine smoking].

BACKGROUND: To explore if cocaine or heroin smoking was positively associated to acute respiratory complications (ARC). SUBJECTS AND METHODS: We collected data from medical records for 717 cocaine users who were attended in 14 hospital emergency rooms. The association was studied by logistic regression. RESULTS: The most frequent ARC were respiratory infections and complications with chest pain or dyspnea. Cocaine smokers (OR = 3.3; CI 95% = 1.5-6.9) and cocaine sniffers (OR = 2.5; CI 95% = 1.1-5.6) had greater risk of ARC than cocaine injectors. Heroin smokers (OR = 3.5; COI 95% = 1.8-7.0) and heroin sniffers (OR = 2.8; CI 95% = 1.4-5.6) had greater risk of ARC than non heroin users. CONCLUSIONS: These results suggest that cocaine or heroin smoking increases the risk of ARC.

Acute Disease↗

Clinical course, microbiologic profile, and diagnosis of periannular complications in prosthetic valve endocarditis.

Whether periannular extension of prosthetic valve endocarditis (abscesses, pseudoaneurysms, fistulas) is related to the etiologic agent, the clinical course and the prognosis is still unknown. Likewise, transesophageal echocardiographic accuracy in detecting periannular complications in prosthetic recipients remains unsettled. We retrospectively analyzed data from 87 patients with anatomically proven prosthetic valve endocarditis who underwent a transesophageal echocardiographic examination. Periannular complications (30 abscesses, 18 pseudoaneurysms, 8 fistulas; 8 with >1) were found in 46 patients; results were compared with the remaining 41 without complications. Transesophageal echocardiography correctly identified 27 abscesses (90%) and all pseudoaneurysms and fistulas. One diagnosis of pseudoaneurysm by echocardiography was not found at surgery. No statistical differences were found regarding age, sex, type of prosthesis (mechanical vs biologic), and etiologic agent. Periannular complications were more frequent in aortic location (70% vs 20% in mitral position; p <0.001) and in early (within 6 months after surgery) endocarditis (63% vs 38% in late endocarditis; p = 0.04). The same percentage of patients from both groups underwent surgery (98% with and 90% without complications). At discharge, 62% and 67% of patients were alive, respectively. Thus, periannular complications in prosthetic valve endocarditis are more frequent in aortic location and within 6 months after surgery. Neither the type of prosthesis nor the etiologic agent are related to the presence of periannular complications. Short-term prognosis in patients who underwent surgery is not affected by the presence of periannular complications.

Abscess↗

Association between educational level and health related quality of life in Spanish adults.

OBJECTIVE: To analyse differences in health by educational level in Spanish adults by comparing the health dimensions of the SF-36 Heath Survey. DESIGN: Data were taken from the National Survey on Drug Use carried out in February 1996. The information was collected by home personal interview. In addition to measuring the use of legal and illegal drugs and their associated health risks, the health status of the Spanish population was analysed using the Spanish version of the SF-36 Health Survey. MAIN OUTCOME MEASURE: Absolute and standardised differences between mean score on each dimension of the SF-36 Health Survey in each educational group with respect to the group with the highest educational level. RESULTS: Perceived health status declines with decreasing educational level, except in women with second level education who have a higher mean rating than women with third level education on various health dimensions. The absolute differences in perceived health between the different categories of educational level and the reference category become larger with increasing age. The greatest differences by educational level in both men and women were found in mental health and general health among persons 25 to 44 years of age, and in physical function and general health among those 45 to 64 years. In persons aged 65 or older, the greatest differences are seen in physical function and vitality in men, and in bodily pain and emotional role in women. CONCLUSIONS: The influence of educational level on the different dimensions of perceived health may vary by sex.

Adolescent↗

[Population reference values of the Spanish version of the Health Questionnaire SF-36].

BACKGROUND: Perceived health status measurements reference values an important information source for health services research. Population-based norms have been proposed to increase their interpretability. In this paper, we have obtained the norms of the Spanish version of the SF-36 Health Survey and have compared them with US norms the questionnaire. MATERIAL AND METHODS: Data were obtained in the home interview survey on drug consumption (February 1996). This is a cross-sectional study of a multi-stage, stratified random sample of non-institutionalized individuals 15 and older residents in Spain. The final sample included 9,984 individuals, but the analysis is based on those individuals 18 or older (n = 9,151). Personal home interviews were carried out. Information included: the SF-36, legal and illegal drugs consumption, and socio-demographic data, among others. Central trend and dispersion statistics were estimated for each of the SF-36 dimension scores according to gender and age group. Cronbach's alpha coefficients were calculated to estimate the reliability of scores. RESULTS: For most SF-36 dimensions, scores were higher (better) among men and among younger age groups (p < 0.01). There was a monotonic score gradient by age which was more intense for physical function and bodily pain. All Cronbach's alpha coefficients were higher than 0.7 (ranging from 0.78 to 0.96). Spanish norms were very similar to those obtained in the US. CONCLUSIONS: Results presented should be considered the population-based norms of the Spanish version of the SF-36 Health Survey and may be useful for interpreting the questionnaire scores. These norms, which are very similar to the original US questionnaire both in absolute values and in the gender and age group distribution patterns, should be carefully used. Considerations for use discussed in the paper should be taken into account.

Adolescent↗