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D Herrera

Publications and source records attributed to D Herrera.

36 records · Page 2Linked to original sources
PubMed1998

[Elective noninvasive test in the diagnosis of coronary disease in the aged].

BACKGROUND AND PURPOSE: The purpose of this study was to determine the best noninvasive test to diagnose coronary artery disease in the elderly. PATTERNS AND METHODS: We conducted a study on 56 elderly patients (> 65 years) with chest pain and no previous history of coronary artery disease. They underwent exercise stress test, dipyridamole echocardiography (0.84 mg/kg), dobutamine echocardiography (up to a total dose of 40 microgram/kg/min and atropine when it was necessary), dobutamine MIBI-SPECT and coronary angiography. RESULTS: Angiography detected significant coronary artery disease in 41 patients. All tests used in this study had a similar sensitivity (conclusive exercise stress test 87%, dipyridamole echocardiography 83%, dobutamine echocardiography 80% and MIBI-SPECT 87%; p = NS). Coronary angiography did not identify significant lesions in 15 patients. Specificity of conclusive exercise stress test, dipyridamole and dobutamine echocardiography was similar (75%, 100% and 93% respectively; p = NS). However, the specificity of stress echocardiography was higher than that of scintigraphy (100% vs 66%; p = 0.02 for dipyridamole echocardiography and 93% vs 66%; p = 0.07 for dobutamine echocardiography). Diagnostic accuracy of each test was similar. CONCLUSIONS: Exercise stress test remains the non invasive diagnostic test of choice to detect coronary disease in the elderly. If this test is inconclusive, both stress echocardiography and isotopic studies are useful, although the specificity of stress echocardiography is higher than that of scintigraphy.

Aged↗
PubMed1997

Oxidation products of cholesteryl linoleate are resistant to hydrolysis in macrophages, form complexes with proteins, and are present in human atherosclerotic lesions.

Accumulation of the insoluble lipid-protein complex, ceroid, is a characteristic of atherosclerotic plaques. To determine whether deficient processing of cholesteryl esters in oxidized (ox) low density lipoprotein (LDL) contributes to ceroid formation, we studied the hydrolysis of internalized [3H] cholesteryl linoleate (CL) in oxLDL by mouse peritoneal macrophages (MPM). The hydrolysis by MPM of [3H]CL incorporated into oxLDL or LDL did not differ, suggesting that products of lipid and/or apoB oxidation had no impact on the lysosomal hydrolysis of [3H]CL. To evaluate the hydrolysis of oxCL by MPM, we subjected extensively ox[3H]CL to fractionation by TLC. The predominant fraction (D) consisted of sterols and oxysterols esterified to scission products of oxidized fatty acids containing terminal carbonyl groups, i.e., lipid core aldehydes. The extent of hydrolysis of [3H]-fraction D by MPM cultures, as well as by MPM extracts at pH 4.0, was significantly reduced when compared to the hydrolysis of intact [3H]CL. Fraction D also formed complexes with serum proteins, and the purified core aldehyde, cholesteryl 9-oxononanoate reacted with epsilon-amino group of lysines. Finally, several cholesteryl ester aldehydes were detected in lipid extracts of human atheroma. These results suggest that decomposition products of extensively oxidized cholesteryl linoleate that are also present in atherosclerotic lesions, are not adequately degraded by mouse peritoneal macrophage lysosomes and could interact with proteins to form ceroid.

Aldehydes↗
PubMed1996

Interregional foodborne salmonellosis outbreak due to powdered infant formula contaminated with lactose-fermenting Salmonella virchow.

Spain's Salmonella surveillance system backed by regionally-based epidemiologists around the country made it possible to detect and halt the spread of a foodborne salmonellosis outbreak due to powdered infant formula contaminated with a lactose-fermenting strain of Salmonella virchow. Forty-eight cases involving children, mostly under 7 months old, were detected in 14 out of Spain's 17 Regions. The outbreak started in January and ended in June 1994. All cases were microbiologically confirmed. The implicated strain had a 3.6 kb plasmid, was susceptible to all antimicrobials tested except nitrofurantoin and was phagetype 4a. Isolates from 8 of 24 Brand "A" milk samples tested had the same characteristics as case isolates. All affected/suspect batches of Brand "A" milk were destroyed and the product withdrawn from sale, which led to the end of the outbreak. This incident underscores the importance of maintaining surveillance systems able to detect and prevent foodborne outbreaks and alert to the possibility of isolating unusual lactose-fermenting Salmonella serotypes in especially sensitive food products.

Animals↗
PubMed1995

Hematological reconstitution and gene therapy: retroviral transfer of the bacterial beta-galactosidase activity into human hematopoietic CD34+ cell populations and into T lymphocytes derived from the peripheral blood.

We report the possibility to transfer marker genes coding for beta-galactosidase activity using retroviral vectors into human peripheral blood CD34+ cells, peripheral blood T-lymphocytes and into the growth factor-dependent human hematopoietic cell line TF-1. Using the MFG-nisLacZ and the FLac vector and various packaging cell lines, we demonstrated retroviral transfer and high expression of a bacterial beta-galactosidase activity induced by the nisLacZ gene or the Sh-ble/LacZ gene. Kinetics of expression of the transgenes were analyzed both in primary cells and cell lines. Absence of cytotoxicity related to the expression of the bacterial beta-galactosidase was assessed in both cell types. These results open interesting prospectives for the use of the beta-galactosidase activity to mark and follow the fate of genetically modified cells isolated from patients prior to reimplantation.

Antigens, CD↗
PubMed1994

Retroviral transfer of the nlsLacZ gene into human CD34+ cell populations and into TF-1 cells: future prospects in gene therapy.

Few data are available concerning behavior of reimplanted human hematopoietic cells after autologous stem cell transplantation. This paper reports the possibility to transfer gene markers coding for beta-galactosidase (beta-Gal) activity by retroviral vectors into a human leukemic growth factor-dependent cell line, TF-1, and into human hematopoietic progenitors isolated from peripheral blood or bone marrow. Using various combinations of retroviral vectors and packaging cell lines, we demonstrated high expression of a bacterial beta-Gal activity induced by the LacZ gene, the nlsLacZ gene, or the Sh-ble/LacZ gene, in human hematopoietic cells. The expression of the nlsLacZ construct was stable until the end of the culture in infected CD34+ cell-enriched cell populations, and a slow decrease of transgene expression was observed in a transduced TF-1 cell population during a 1-year long-term culture. Data obtained with the nlsLacZ gene demonstrate that both retroviral transfer and corresponding gene expression were not found to modify the pattern of cell proliferation and differentiation. These results open interesting prospectives for the use of the nlsLacZ gene to mark and follow the fate of progenitor cells isolated from patients with cancers prior to reimplantation.

Animals↗
PubMed1994

[Tricuspid endocarditis caused by penicillin-resistant Staphylococcus aureus: 2 cases in parenteral drug addicts].

BACKGROUND: Staphylococcus aureus is the main causal agent of infectious endocarditis (IE) in intravenous drug addicts (IVDA) with most of the strains, isolated in Spain being resistant to penicillin and sensitive to methycillin, although the latter condition varied in recent years. Two cases of IE caused by S. aureus strains sensitive to penicillin in IVDA are presented. METHODS: All bacteremia episodes diagnosed in the Hospital General Penitenciario (Madrid) over a 33-month period (March 1991 to December 1993) were prospectively studied. Special attention was given to patients diagnosed of IE. Blood cultures were processed according to the usual technique by a non radiometric system. RESULTS: One hundred and four bacteremias were detected with 14 being produced by S. aureus. Ten episodes of the total number of bacteremias fulfilled criteria for IE with 2 being produced by strains of S. aureus sensitive to penicillin (CMI < 0.06 mu/ml). Both patients had coinfection by HIV. The clinical evolution prior to diagnosis was prolonged although clinical and microbiologic cure were achieved with intravenous beta-lactam antibiotics treatment, without complications. CONCLUSIONS: Despite the low incidence of the isolation of Staphylococcus aureus sensitive to penicillin (< 3%) recently observed in Spain, strains producing severe infections, showing patterns of sensitivity such as those found during the preantibiotic era, may still be isolated.

Adult↗
PubMed1978

Inherited congenital normofunctional testicular hyperplasia and mental deficiency. A corroborative study.

Three 46,XY unrelated individuals out of 84 postpubertal male inpatients with severe mental deficiency in a psychiatric hospital were found to have megalorchidia and macrogenitosomia. One of the cases had a similarly affected brother. Endocrine studies were performed in two of the cases with similar results. Normal plasma levels of pituitary gonadotropins were found. A normal testicular function was demonstrated by the finding of normal: (a) baseline plasma testosterone levels and a significant rise following human chorionic gonadotropin administration, (b) sperm analysis, and (c) morphology and cell architecture of the testes. These results were compatible with normofunctional testicular hyperplasia confirming previous observations and allowing the definite individualization of a syndrome with mental deficiency probably due to an X-linked recessive mutation.

Adult↗
PubMedDate not supplied

[Estimating the completeness of AIDS reporting in Spain].

OBJECTIVE: To evaluate AIDS case reporting in the Spanish regions as compared with the AIDS deaths registered in mortality statistics, in order to identify possible deviations indicative of underreporting. METHODS: We carried out an ecological analysis taking each region as a unit. We compared incidence and mortality obtained from the AIDS reporting system with the HIV/AIDS deaths obtained from the mortality statistics of the Spanish Institute for Statistics. The 1986-1998 period was analysed globally, then the analysis was repeated for the 1995-1998 period. RESULTS: In the 1986-1998 period there was a good correlation (r = 0.93) between the AIDS incidence rates and HIV/AIDS mortality rates obtained from death statistics. Some regions presented an AIDS incidence lower than expected according to their mortality rate when it was compared with the national average, with Asturias (27%), Comunidad Valenciana (26%), Andalucia (20%), Ceuta (18%) and Cantabria (13%) standing out. Taking as a reference the five regions with the highest completeness, the underreporting in Spain was of 13%. In the 1995-1998 period these deviations increased moderately. In the 1986-1998 period, 18.9% less deaths were notified to the AIDS reporting system in comparison with death statistics, showing a great variability between regions. CONCLUSIONS: In Spain the reporting level of AIDS cases is acceptable for the aims of surveillance, although in some regions measures to improve it should be taken. The notification of deaths to the AIDS reporting system presents great deficiencies.

Acquired Immunodeficiency Syndrome↗
PubMedDate not supplied

[Chickenpox outbreak in Herrera del Duque, Badajoz, Spain].

INTRODUCTION: Chickenpox is a worldwide disease with high morbidity but few complications, although complications can be sevre in immunocompromised individuals and healthy adults. The annual chickenpox rate declared to the National Notification Disease Surveillance System is approximately 5 cases per 1,000 inhabitants in Extremadura (Spain). The aim of this study was to identify and describe the characteristics and cost of an epidemic outbreak of chickenpox in Extremadura. METHODS: Between November 2000 and March 2001, a descriptive study was performed. Cases of chickenpox were actively sought in a cohort of schoolchildren in Herrera del Duque (Badajoz). The protocols of the Monitoring Network of the Autonomous Community of Extremadura was used for case definition. Microbiological confirmation was performed by isolation of the virus and the presence of IgM and IgG markers in serum. We analyzed the direct and indirect tangible costs as well as the intangible costs of the outbreak. RESULTS: Seventy-five cases were identified, of which 94.7% occurred in children aged between 1-9 years, mainly boys. The attack rate was 18.5 cases per 1,000 inhabitants and 68.2% occurred in children aged less than 10 years charing a home. The clinical course was benign, without hospital admissions or complications. A total of 71.6% of children aged between 3 and 8 years were susceptible. A possible temporary aggregation of cases in the school was analyzed and a relative risk of 5.01 (p < 0.0001) was obtained. The virus was isolated in the 4 vesicle samples studied and serology was positive (IgM) in the 9 serum samples studied. The total cost of the outbreak was of 927,21 e, with a mean of 12,53 e per case and 205 school days lost. CONCLUSION: A chickenpox outbreack was confirmed in Herrera del Duque, with person-to-person transmission, affecting children aged between 1 and 9 years. The high susceptibility of the pupils, the characteristics of teaching, and the meetings prior to the carnivals played a determining role in the transmission of the epidemic. The estimated cost of this outbreak was 76% less than the cost that would have been generated by single-dose vaccination of the 75 individuals who contracted the disease.

Chickenpox↗
PubMedDate not supplied

[Estimation of the use of seat belts: an observational study and a telephone survey].

OBJECTIVE: To estimate the prevalence of safety-belt use in a telephone survey and an observational survey. PATIENTS AND METHODS: Observational survey. Trained interviewers studied 4,067 front-seat occupants, at ten intersections of Madrid, according to "National Highway Traffic Safety Administration" guidelines. TELEPHONE SURVEY: We selected 433 front seat occupants from the Madrid city residential telephone directory. The questionnaire was completed by trained interviewers. RESULTS: Prevalence by the observational survey was 58.5%, and was significantly higher at interurban intersections (OR = 2.1) than city intersections. In the telephone survey, the overall prevalence was 94% at interurban area and 64% at city area and it was associated with no history of lines and positive opinion of effectiveness of safety belts. CONCLUSIONS: The safety belt prevalence observed is low, especially in the urban area. The telephone survey overestimates the safety belt use, but contributes with useful information for planning strategies.

Adult↗
PubMedDate not supplied

Associated release of magnesium and phosphorus from active and abandoned dairy soils.

Dairy manure application to soils can result in phosphorus (P)-related degradation of water quality. The P in these manure-impacted soils can be labile even years after abandonment and under conditions normally associated with high P stability. Failure of P to stabilize with time compounds the environmental consequences of dairy manure disposal, especially on sandy soils. The objectives of this study were to compare chemical characteristics of active and abandoned dairy manure-impacted soils and minimally impacted soils and to assess the continuous release of P in relation to sparingly soluble salts using repeated water extractions, X-ray diffraction, and speciation modeling of column leachates. Soil samples from Ap horizons were collected from nine highly manure-impacted (total P > 1000 mg P kg(-1) soil) areas on four active and five abandoned dairies and four minimally impacted soils (total P < 200 mg P kg(-1) soil). Soil extracts were analyzed for electrical conductivity (EC), soluble reactive phosphorus (SRP), Ca, Mg, Na, and K. The EC of the soil solutions decreased as active dairy > abandoned dairy > minimally impacted soils. Release of Mg and SRP were significantly correlated (r2 = 0.68) and did not decline after abandonment; Ca release was not correlated with SRP (r2 = 0.01), and declined significantly (p < 0.05) after abandonment. Speciation data from column leachates suggested that Mg-P phases and/or the most soluble Ca-P phases could control P solution activities. An implication of this study is that P stabilization via crystallization of calcium phosphates (even at near-neutral pH) may be preempted by Mg-P association. Thus, mechanisms to minimize P release may require P-retaining soil amendments or management of animal rations to eliminate Mg-P formation.

Animals↗
PubMedDate not supplied

[Comparative study of Salmonella and Campylobacter infections in Huesca. 1996-1999].

BACKGROUND: The Salmonella and Campylobacter genera are the main bacterial agents causing enteritis in humans in the developed countries. The purpose of this paper is to study the descriptive characteristics of the cases of infection by Salmonella and by Campylobacter and to describe their trend and seasonal variance in the province of Huesca for the 1996-1999 period. METHOD: The sources of information were the Hospital Microbiological Laboratories (HML's) which conduct coproculture analyses of both outpatients and inpatients. The municipality is taken as the reference unit for plotting the space distribution. For the study of the trend, a multiplicative determinist model is used for grouping the data into four-week periods. RESULTS: A total of 781 cases of infection by Salmonella and 654 cases of infection by Campylobacter have been included, respectively showing mean annual rates of 95 and 79.5 x 10(5) inhabitants. The enteritis by Campylobacter occurs mainly in children under five years of age (73.4%), as compared to the 35.5% of the cases of salmonellosis. The situation is the reverse in the case of the hospital admission percentages, hospitalization due to salmonellosis hence being nearly five times greater. Both of these genera are of a clear-cut seasonal nature, showing a marked peak in the month of August. CONCLUSIONS: A growing trend in the number of positive isolations for both of these organisms and a clear seasonality in the summertime have been found.

Adolescent↗
PubMedDate not supplied

[Relation between pulmonary tuberculosis and the urinary tract].

We have studied 48 children that presented lung tuberculosis together with the effects tuberculosis has on the urinary apparatus. Clinical, laboratory and radiotherapeutic studies were made in order to confirm the diagnosis which was etiologically confirmed in only two cases. In order to make a good diagnosis it is necessary to use a good technique for urine collection with serial cultures corresponding to four consecutive days and the radiological study of the kidney and its afferent ducts. It is an illness more common than what is thought. It is necessary to know how to detect it and it is very important to have it "in mind" when dealing with any generalized tuberculosis disease: (miliary tuberculosis, meningoencephalitic tuberculosis, etc.). With this article, it has been our purpose to contribute to review and to bring up to data the clinical and pathophysiological concepts of this disease.

Child↗