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E Medina

Publications and source records attributed to E Medina.

At least 19 recordsLinked to original sources
PubMed1995

[Importance of HDL cholesterol determination in the evaluation of coronary risk in clinical practice].

OBJECTIVE: To validate to what extent the isolated determination of total Cholesterol (TC) is effective when seeking to predict coronary risk. DESIGN: An observational crossover study of the analytic determinations of the clinics which systematically request TC and HDL-Cholesterol (HDL)--case-finding method. SETTING: Health Centre. PARTICIPANTS: 631 analytic determinations, with samples from people who attended a Health Centre between May and November 1992, were studied. MEASUREMENTS AND MAIN RESULTS: As proof of certainty the Atherogenic Index (AI) was used for the relative risks (RR) of suffering a coronary event in line with the Framingham study. The confidence limits (CL) were calculated to 95% in order to quantify random error and permit comparison. On varying the cut-off points of TC the indicators changed, being more sensitive (S) and less specific (E) with the lower figures: 180 mg/dl, RR > 1, S = 97.5% (CL: 100-94.7) and E = 30.5% (36.8-24.2); RR > 2, S = 100%, E = 22.1% (26.9-17.3) and RR > 3, S = 100%, E = 20.8% (25.3-16.3). As values of TC increase, S diminishes and E increases: 250 mg/dl, RR > 1, S = 48.3% (57.2-39.4), E = 87.2% (91.8-82.6); RR > 2, S = 58.6% (76.5-40.7), E = 77.2% (82-72.4) and RR > 3, S = 63.6% (92-35.2), E = 75.3% (80.1-70.5). CONCLUSIONS: HDL must be determined if TC is -200 mg/dl. If everyone with RR > 2 is to be detected, HDL-cholesterol from TC > or = 180 mg/dl must be measured.

Adult↗
PubMed1995

Liver transplantation in patients with Budd-Chiari syndrome.

Patients with Budd-Chiari syndrome (obstruction of the hepatic veins) and associated hepatic insufficiency may be candidates for orthotopic liver transplantation (OLT). In our series of 405 OLT patients, 3 were transplanted due to Budd-Chiari syndrome (0.7%). The indication for liver transplantation in these patients was severe hepatic insufficiency (chronic in two and acute in the third one). Morphologic study of the obstructions revealed apparently different causes, including thrombi, membranous webs in hepatic veins, and hydatid cyst compression. The surgical technique employed in these transplantations was similar to that for other etiologies. Due to its implications for the future course of OLT, it is important to determine the exact etiology of Budd-Chiari syndrome in the pretransplant period and to treat the patients with early and long-term anticoagulant therapy to avoid syndrome recurrence.

Adolescent↗
PubMed1995

[Medical care in Santiago, 1993].

Results of morbidity and medical care surveys performed in Santiago in 1993-94 are presented in this paper. The study has been done in an aleatory population sample of 4,700 people coming from 1,000 dwellings. Main results are as following: The Health National Fund (FONASA) is the most important financing medical care's agency in Santiago (49% out of total population). A majority of medical services are given in private offices or clinics. Medical care systems show significant differences among the studied city districts. A significant direct correlation between people's income and private practice is noticed. One half of acute diseases had medical care and the other half used self care practices; the proportion of medical care is 29% in the case of chronic disease patients. National Health Service eligible people show a significant higher morbidity rate and medical consultation rate than other groups. Lack of medical care mainly depends on low severity of illness episodes or lack of symptoms in chronic disease conditions. In 12% out of total cases, lack of medical care was due to problems in the medical care systems. The quality of care was judged "good or excellent" by 82% of the people, "fair" by 9%, and "bad or deficient" by the remaining 8%. Personal expenditures due to health care are high, one third depending on medical care and two thirds on dental care. In the case of medical care the reasons for expenditures are linked to chronic diseases (60%), acute diseases (28%), injuries and health examinations (15%). Main activities causing personal disbursements are the purchase of drugs (44%), medical visits (30%), laboratory tests (13%) and hospital charges (7%).(ABSTRACT TRUNCATED AT 250 WORDS)

Chile↗
PubMed1995

[Does the antisecretory agent used affect the evolution of upper digestive hemorrhage?].

OBJECTIVE: To investigate whether omeprazole has improved morbidity-mortality among patients with upper gastrointestinal bleeding of non-variceal origin in comparison with ranitidine. MATERIAL AND METHODS: Prospective, randomized and open study. We study 519 consecutive patients admitted to our Service between June 1991 and January 1993 for upper gastrointestinal bleeding of peptic origin, dividing the patients into two randomized groups that were homogeneous in terms of age, sex, previous history of gastric disease and upper gastrointestinal bleeding, intake of non-steroidal antiinflammatory drugs, and the severity of bleeding on admittance. Thus, Group A consisted of 252 patients treated immediately upon arrival at the emergency ward with 50 mg intravenous ranitidine, followed by a further 50 mg every 6 hours. Group B in turn consisted of 267 patients initially given a bolus dose of 80 mg omeprazole intravenously, followed by an additional 40 mg every 8 hours for 48 hours. Forty mg were subsequently administered every 12 hours until hospital discharge. Endoscopy was performed in all cases within the first 24 hours following admittance, those patients with active upper gastrointestinal bleeding resulted from Forrest-type ulcer of subjected to endoscopic sclerotherapy were excluded. RESULTS: Duodenal ulcer was the most common cause of bleeding, followed by gastric ulcer and acute lesions of the mucosa. Emphasis should be placed on the high incidence of previous non-steroidal antiinflammatory drug intake in our series (54.5%). We encountered no statistically significant differences between the two groups on comparing bleeding stigmata, transfusion requirements, recurrences, emergency surgery, the duration of hospital stay, and mortality. CONCLUSIONS: Both drugs were found to possess a similar efficacy in treating upper gastrointestinal bleeding of peptic origin.

Adolescent↗
PubMed1995

[Prevalence of digestive symptoms in normal adult women and its association with cholelithiasis].

The aim of this work was to study the prevalence of biliary diseases and digestive symptoms in normal adult women. Four hundred nineteen women were chosen; of these 145 were discarded due to previous gastrointestinal diseases (20), previous gastrointestinal complaints (38) and previous cholecystectomy (85). Two hundred seventy six women were subjected to abdominal ultrasound examination; of these 53 had cholelithiasis and in three a gallbladder cancer was suspected (and confirmed by surgery). Considering women with previous cholecystectomy, cholelithiasis and gallbladder cancer, a 33.6% prevalence of biliary diseases can be inferred. An interrogation about gastrointestinal symptoms was performed to women subjected to ultrasound examinations, by 2 professionals unaware of ultrasound results. A high frequency of pyrosis, food intolerance and constipation was found, not observing differences between women with or without cholelithiasis. However, these last women had a higher frequency of upper abdominal pain. Both groups had also a high rate of previous surgical procedures.

Adult↗
PubMed1994

Lymphocyte activation in HIV-1 infection. II. Functional defects of CD28- T cells.

OBJECTIVES AND DESIGN: The expression of the accessory molecule CD28 was compared in various populations of T and natural killer (NK) cells from HIV-1-negative and HIV-1-positive individuals and correlated with activation using mitogens in vitro. METHODS: Multiparameter flow cytometric analysis using combinations of CD3 CD28 and other markers was performed together with absolute cell counting in peripheral blood. Blast transformation and proliferative responses were also quantitated using the Cytoronabsolute after stimulation with phytohaemagglutinin (PHA) and anti-CD3. CD28- cells were also purified to confirm the observations. RESULTS: In HIV-1-negative individuals > 90% of CD3+ T cells were CD28+ and responded to stimulation, while CD3- CD16+ CD57+ NK-like cells were CD28- and failed to respond. In HIV-1-positive individuals the expression of CD28 was greatly reduced and the proportion of CD3+CD28- T cells expanded. CD8 lymphocytosis was caused entirely by the accumulation of CD28- T cells and many of these expressed activation markers human lymphocyte antigen-DR, CD38 and CD45RO on their membrane and molecules such as TIA-1 and perforin, associated with cytolytic function, in their cytoplasm. The strong positive correlation (r = 0.66) between the lack of CD28 expression and the poor proliferation from HIV-1-positive individuals was confirmed by demonstrating that only CD28+ cells transformed into lymphoblasts and proliferated. Although the CD28- including CD3+ T cells transiently expressed CD25 (interleukin-2R alpha), they did not undergo blastogenesis or activation measured by bromodeoxyuridine uptake and died after 3-4 days in culture. These observations were confirmed in costimulation experiments with anti-CD2 and anti-CD28. CONCLUSION: In HIV-1 infection activated CD3+CD28- T cells accumulate but are unresponsive to mitogens and anti-CD28. These cells appear to represent terminally differentiated effector cells which fail to respond to further stimuli because of the absence of a CD28 second signal.

Adult↗
PubMed1994

Flow cytometric analysis of the stimulatory response of T cell subsets from normal and HIV-1+ individuals to various mitogenic stimuli in vitro.

A novel technique is described which allows the study of the responses of T cell subpopulations stimulated in bulk cultures without interfering with cell-cell interactions. The number and phenotype of lymphoblasts developing following stimulation with phytohaemagglutinin (PHA), anti-CD3, staphylococcal protein A (SPA) and pokeweed mitogen (PWM) was determined in HIV-1- and HIV-1+ patients using a new five-parameter flow cytometric method. We found that normal T cells responded faster to PHA than to any of the other mitogens tested. The peak of the PHA response occurred on day 3, followed by anti-CD3 and SPA on day 4 and PWM mitogen on day 5. Although PHA and anti-CD3 stimulated up to 95% and 80% of lymphocytes, respectively, SPA and PWM stimulated only 40% and 30% of cells, respectively. A defective T cell response was observed in lymphocytes cultured from asymptomatic HIV-1+ patients compared with negative controls. This loss of response was related to a selective mortality of T cells following mitogenic stimulation, referred to as activation-associated lymphocyte death (AALD). The results showed that stronger mitogens (PHA and anti-CD3) induced AALD in a larger proportion (50-60%) of T cells than weaker mitogens such as SPA and PWM (30-40%), and that AALD affected different lymphocyte subsets to different extents. AALD occurred more frequently in total CD8+ and CD45RO+ T cells compared with CD4+ and CD45RA+ T cells, but memory CD4+ T cells were the population most severely affected in samples from HIV-1+ donors.

Acquired Immunodeficiency Syndrome↗
PubMed1994

Recurrence rate after accessory pathway ablation.

OBJECTIVE: To evaluate characteristics of patients and accessory pathways as well as additional technical factors involved in the reappearance of accessory pathway conduction after successful ablation. DESIGN: Analysis of recurrences after radiofrequency ablation. SETTING: 163 consecutive patients with 167 accessory pathways. SUBJECTS: 97 men and 66 women with a mean (SD) age of 36 (14) range (11 to 75) years. RESULTS: After a mean (SD) follow up of 14 (7) range (2 to 27) months, conduction recurred in 13 out of 167 (7.8%) accessory pathways. The initial manifestation of recurrence was circus movement tachycardia in 7 patients and reappearance of delta waves on a 12 lead electrocardiogram in 6 patients. The interval to the return of accessory pathway conduction ranged from 3 hours to 90 days. Age, sex, presence of multiple accessory pathways, criteria to determine the target ablation site, number and duration of radiofrequency applications, and cumulative energy did not significantly differ between the groups with recurrence and without. Recurrence was less common with concealed accessory pathways (2/44) than with overt accessory pathways (11/110). The difference was not significant. The only variable to influence the recurrences in this study group was the location of the accessory pathway. Reappearance of conduction through right sided accessory pathways occurred significantly more often than through left sided ones (8/40 v 5/114, P = 0.01). CONCLUSION: After radiofrequency ablation the recurrence rate of accessory pathways is low and there are no predictors of the risk of reappearance of conduction apart from the right sided location of the accessory pathway.

Adolescent↗
PubMed1994

[Attitudes and behaviour concerning tobacco use among physicians from Santiago].

The aim of this work was to study the prevalence, behavior and opinions towards smoking in a sample of 288 physicians from Santiago, stratified according to sex and specialty. The WHO Europe questionnaire was applied and smoker was defined as the person that consumed one or more cigarettes per day. Thirty six percent of the sample (40.2% of men and 23.8% of women) smoked an average of 9 cigarettes per day, compared to the figure of 28.3% obtained in a similar study in 1983. Fifty percent of smokers felt that they will not quit. No differences in knowledge about problems associated to smoking or forbidding smoking in hospitals, were observed between smokers and non-smokers. A majority of smokers did not smoke in front of their patients and did not allow smoking in their private clinics. It is concluded that, although a high proportion of physicians continue to smoke, their opinions and behavior will support smoking cessation efforts.

Adult↗
PubMed1994

[Characteristics and management of morbidity in Santiago 1993].

Results of morbidity and medical care surveys of the Santiago's population are presented in this paper. A random sample of 1,000 dwellings with 4,700 people was selected and studied 3 times, in 1993 and 1994. All health events (acute and chronic morbidity, health examinations, dental care) and main features of medical care were registered in the interviews which covered a 2-week period each time. The population sample had similar characteristics than the results of the last Population and Dwellings Chilean Census. Health events were registered with high frequency: 56% of the families had one or more members with chronic disease; 51% with acute diseases; 46% with emotional troubles; 24% had dental care; 17% health examination and 6% different types of injuries. Frequency of medical care during the fortnight period was 5.6% out of total population of acute diseases; 1.0% of injuries; 4.9% for chronic diseases, 3.9% of health examinations and 5.6% of dental care. Frequency of diseases was significantly higher among women (50%) than in men (33%) and in poor people than in higher socioeconomic levels. Most of the acute disease were respiratory illnesses followed by communicable diseases, skin troubles and rheumatologic disorders. The most important detected chronic diseases were blood hypertension, diabetes mellitus, bronchial asthma and alcoholic addiction.(ABSTRACT TRUNCATED AT 250 WORDS)

Accidents↗
PubMed1994

[Celebration of the 50th anniversary of the School of Public Health of the University of Chile].

The joined initiative of the University of Chile, the Health institutions, the Bacteriological Institute and the Rockefeller Foundation support allowed the creation of the School of Public Health. A group of skilled and talented young specialists gave rise to the School, as an expression of the need to refurbish the medical care of the forties. The aim of the School was to communicate the scientific basis of sanitary practice, to study national problems and to group people that can contribute to improve the health status of the country. During fifty years, the number of Chilean and foreign students expanded considerably. During these five decades the School has trained 1588 specialists (459 foreigners) in Public Health. The School was awarded by WHO in 1988 in recognition of its outstanding contributions to Public Health. It is difficult to make adequate decisions at the present time, due to the complexity of Chilean health situation, that is going through an epidemiological and demographic transition. A systematic effort to investigate and to train people in public health and health administration is mandatory. These are the principal tasks of the School, that maintains its fifty years tradition left by its founders.

Chile↗
PubMed1992

[Clinical course characteristics of gastric cancer 1958-1990].

The clinical, surgical and histopathologic characteristics of patients with gastric cancer were compared among 3 consecutive periods from 1958 to 1990. A significant increase in the frequency of location at the upper third of the stomach, a greater proportion of resectable lesions, an increasing tendency towards extended total gastrectomy and a significant increase in the frequency of undifferentiated or diffuse carcinoma were observed. A change in pathogenetic factors along the years may be involved in the differences described.

Adult↗
PubMed1992

[A cooperative study on early and intermediate gastric cancer: clinical, diagnostic and therapeutic aspects].

A cooperative study involving 13 hospitals in Chile allowed the analysis of 353 patients with gastric cancer in early stages. 82 cancers were located at the mucosal level, 151 at the submucosa and 120 reached the muscular layer. There were no differences in age and sex among these groups. Compared to early stage, patients with intermediate stage had a greater incidence of bleeding, anemia and undernutrition and exhibited lower body weight. Endoscopy had a higher diagnostic yield compared to radiological study. The diagnosis was confirmed by biopsy in 95% of patients. Total or subtotal gastrectomy was performed according to the location of the lesion, with a low operative mortality rate. Early gastric cancer accounts for 8 to 10% of all patients with gastric cancer undergoing surgical treatment.

Adult↗
PubMed1992

[Hospitalization in Chile: a critical analysis].

Main features of hospital stay in Chile are analyzed with special regard to incidence, geographic, sex and age variations, main causes and trends observed in the last decades. The annual admission rate in 1989 was 107 per 1000, twice the overall Latin American rate. Wide variations are observed among geographical areas, with relatively low use of hospital beds in the capital city of Santiago. Hospital needs differ for men and women and according to age, being greater for infants, older people and women of childbearing age. Near two thirds of the needs are related to pregnancy. Admissions for traumatic, digestive, respiratory, urinary and gynecological problems are also frequent. Accidents are the main cause for hospital admission among males, while tumor is foremost among women. During the last 30 years the hospitalization rate has remained stable while the case fatality rate has decreased. Different factors influencing the frequency and features of hospital stay are discussed.

Adolescent↗
PubMed1992

[Chilean hospitals: availability and productivity of the public and private sectors].

Hospital bed availability, trends in number of beds, productivity and administrative aspects in the public and private hospital sectors are analyzed. At present, there are 3.3 beds per 1000 population in Chile. This represents a decrease from previous figures, in spite of increasing demands derived from population aging and greater birth assistance needs. Overall productivity of the hospital system is reflected in 31 annual admissions per bed, an average hospital stay of 8 days and a 75% occupancy rate. The National Health Service System is responsible for 76% of admissions. However, it takes care of more than 90% of bed needs for tuberculosis patients and more than 80% for hospital birth assistance, complications of pregnancy, perinatal disease, communicable diseases, respiratory illnesses, miscarriages and skin diseases. The private sector takes care of more than 40% of rheumatic and musculo skeletal diseases and more than one third of mental health problems. The National Health Service, compared to the private sector, exhibits a greater occupancy rate with an average stay only one day longer. Complexities of hospital administration, new world trends and the relation to external economic resources are discussed.

Bed Occupancy↗