Scielo RSS <![CDATA[Revista médica de Chile]]> http://www.scielo.cl/rss.php?pid=0034-988720000004&lang=es vol. 128 num. 4 lang. es <![CDATA[SciELO Logo]]> http://www.scielo.cl/img/en/fbpelogp.gif http://www.scielo.cl <![CDATA[La autoría en los manuscritos publicados en revistas biomédicas]]> http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0034-98872000000400001&lng=es&nrm=iso&tlng=es Multiauthorship shows an increasing trend in biomedical and other scientific journals. A main concern for editors, reviewers and readers is to find out whether all individuals enlisted as authors actually fulfill criteria for authorship as defined in the document "Uniform Requirements for Manuscripts Submitted to Biomedical Journals". Revista Médica de Chile is addressing this relevant topic with a combined strategy: (1) A retrospective analysis of the manuscripts published in the recent decades in the Revista will quantify and illustrate the local trend in multiauthorship; (2) A "Statement of accountability": signed by all authors in manuscripts submitted to the Revista, is in use since 1997; and (3) A new form of this "Statement of accountability" requests all authors to identify their personal involvement in the work represented by the manuscript. This information will be available to every person participating in the editorial assessment of the manuscript (editors and external reviewers) but during a trial period of six months authors will be allowed to object the publication of this data, stating the reasons for this objection. After six months the editors will evaluate the information collected and the self-declared role of every author enlisted. The terms "Authors" and "Main author" will continue being used to designate participants because "contributor" (replacement alternative proposed by Rennie et al., currently in use by several leading general medical journals) has a different main meaning in Spanish than in English and it might have a negative effect. (Rev Méd Chile 2000;128: 363-6) <![CDATA[Tratamiento de la infección por <I>Helicobacter pylori</I> en pacientes con úlcera duodenal: Estudio de costo-beneficio]]> http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0034-98872000000400002&lng=es&nrm=iso&tlng=es Background: Epidemiological differences suggest that treatments for H. pylori eradication should be locally validated. Aim: To perform a cost benefit study of different treatment options for H. pylori infection. Patients and methods: One hundred and sixty-seven patients with active duodenal ulcer and H. pylori infection who completed a 2-week treatment with one of the following regimens were included: famotidine plus amoxycillin plus metronidazole (FAM), omeprazole plus amoxycillin plus tinidazole (OAT) or lansoprazole plus clarithromycin plus amoxycillin in 3 (LAC1) or 2 (LAC2) daily doses. We compared efficacy, adverse effects and cost. Results: Eradication rate was 74.6, 72.9, 96.4 y 91.7% for FAM, OAT, LAC1 and LAC2 respectively (p<0.05). Direct cost ranged from US$ 50 for FAM to US$ 220 for LAC1. A decision analysis was carried out in a model including direct and indirect costs and considering retreatment with antibiotics after the first treatment failure and one-year treatment with H2-blockers in case of a second failure. FAM was selected as the most cost-effective option, with an estimated cost of about US$ 300 ± 148 per patient. However, cost associated to LAC2 was very similar (US$ 320 ± 58) and the lower standard deviation suggests less variation. Sensitivity analyses, considering reasonable fluctuation in parameters such as eradication rate, cost and follow-up period suggest that a regimen containing a proton pump inhibitor, clarithromycin and amoxycillin may be the most cost-effective treatment. Conclusions: These results should be confirmed in other settings, specially in ordinary clinical practice, far from clinical research. (Rev Méd Chile 2000; 128: 367-77) <![CDATA[Inmunosenescencia: pruebas cutáneas de hipersensibilidad retardada en adultos mayores chilenos autovalentes]]> http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0034-98872000000400003&lng=es&nrm=iso&tlng=es Background: Delayed cutaneous hypersensitivity tests are a globally accepted test to assess cellular immunity in vivo. The quality and quantity of the response to these type of tests, varies in different populations. Aim: To study delayed cutaneous hypersensitivity in a group of healthy Chilean elders. Material and methods: Forty two elders (32 male), aged 60 to 76 years old were studied. Multitest-CMI® was applied in the left forearm. This test allows the subcutaneous administration of seven antigens and a glycerin control. Results were compared with those of a group of young adults studied by the authors. Results: Among males there was a mean of 2.7 ± 1.4 positive responses compared with women, that had 1.7 ± 1 positive responses (p= 0.016). The sum of response diameters was 4.2 ± 1.5 and 3.6 ± 1.9 mm in men and women respectively (p = NS). Compared to young adults, elderly women had a lower response to tetanus and diphtheria toxoids and men had a lower response to diphtheria and Proteus mirabilis. Conclusions: Elderly people have a less intense response to delayed cutaneous hypersensitivity tests than young adults. This response must be assessed in each population to account for regional variability. (Rev Méd Chile 2000; 128: 379-86). <![CDATA[Efecto de dosis bajas de calcitonina sobre la remodelación ósea en mujeres postmenopáusicas con alto recambio]]> http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0034-98872000000400004&lng=es&nrm=iso&tlng=es Background: Calcitonin is specially indicated for the treatment of osteoporosis in women that cannot receive estrogen replacement therapy or that have a high bone turnover rate. Aim: To study the effects of low intranasal calcitonin doses on bone remodeling in postmenopausal women with a high bone turnover. Patients and methods: Forty one healthy women aged 56 ± 6 years old, with a mean lapse after menopause of 7.6 ± 6.5 years and with a high bone turnover rate, evidenced by an urinary hydroxyproline (mg/dl)/creatinine (g/dl) ratio of 52.4 ± 7.2, were studied. They were randomly assigned to receive 100 or 50 U/calcitonin thrice a week during 3 months or to a control group that received placebo. All received 500 mg/day calcium carbonate. Urinary hydroxyproline/creatinine ratio was measured a 0, 15, 30, 60 and 90 days. Plasma bone fraction of alkanine phosphatases was measured at 0, 30 and 90 days. Results: Initial urinary hydroxyproline/creatinine ratio and plasma bone fraction of alkanine phosphatases were similar in all study groups and there was no change in these parameters during the study period. Conclusions: Intranasal calcitonin in doses of 100 U thrice a week or less, does not modify accelerated bone turnover in postmenopausal women. (Rev Méd Chile 2000; 128: 387-91) <![CDATA[Mortalidad por anomalías congénitas en Chile (1969-1997)]]> http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0034-98872000000400005&lng=es&nrm=iso&tlng=es Background: Congenital malformations are defined as those structural, metabolic or functional defects found at birth. Aim: To study the mortality due to congenital malformations in Chile between 1969 and 1997, their type, individual, temporal and geographic variations. Material and Methods: A descriptive analisis of deaths registered by the National Statistics Institute and the Ministry of Health. Means, frequencies, raw and adjusted rates were calculated and inferences for some variables were carried out. Results: Between 1969 and 1997 ther was tendency towards a reduction in rates of mortality due to congenital malformations and an increment in their relative importance. During the period, the risk for chromosome (98%) and osteomuscular (67%) malformations increased. Men and children of less than one year had the higher risk. In 1995, 1167 deaths due to congenital malformations were registered, 90% in children of less than 5 years. Higher risks occurred in urban zones (with a rate of 8.25 per 100.000) in the third region (rate 11.59) and second region (rate 11.2). Most deaths occurred in hospitals (85%). Main causes of death were circulatory system, central nervous system and chromosome malformations. Conclusions: The differences in regional deaths due to congenital malformations suggests specific risks that deserve further study. (Rev Méd Chile 2000; 128: 392-98). <![CDATA[Malformaciones congénitas y exposición a pesticidas]]> http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0034-98872000000400006&lng=es&nrm=iso&tlng=es Background: Chronic pesticide exposure is a recognized risk for human health. The frequency of congenital malformations in exposed people, can be used for epidemiological studies assessing reproductive risk secondary to toxic exposure. Aim: To study the association between the incidence of congenital malformations and parent’s exposure to pesticides. Material and methods: A prospective study of cases and controls. The exposure could be caused by occupational activities or residence around fumigated crops. The records of cases and controls from the surveillance carried out in the Hospital Regional de Rancagua were analyzed. This hospital is active member of a collaborative study of congenital malformations in Latin America. Results: In two years there was a total of 453 newborns (18 stillborn) with congenital malformations, with an incidence of 41.24 ‰. Considering only children born alive, the paired analysis of cases and controls showed an association of congenital malformations with a history of maternal exposure, with an attributable fraction of 54.4%. Conclusions: These results, showing an association between pesticide exposure and congenital malformations, should be analyzed in the future by a logistic regression test. (Rev Méd Chile 2000; 128: 399-404) <![CDATA[Cáncer tiroideo.: Comunicación de 85 casos]]> http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0034-98872000000400007&lng=es&nrm=iso&tlng=es Background: Thyroid cancer is the most frequent endocrine cancer with important implications in terms of diagnosis and treatment. Aim: to report a population of patients with thyroid cancer diagnosed by pathological studies of the surgical piece. Patients and methods: Eighty five patients (68 female) with the definitive diagnosis of thyroid cancer were studied. Clinical, imaginological, cytological and pathological findings were analyzed. Results: The age range of patients was 10 to 77 years old. Sixty nine patients had ultrasonographic studies which showed a solid nodule in 84%, mixed solid-cystic area in 14.5% and a purely cystic nodule in 1.5% of the cases. Nineteen patients had non specific calcifications. Fine needle aspiration cytology was negative for malignancy in eight patients (false negative rate of 9.9%). The average size of the nodules was of 2.8 ± 1.6 cm). Six nodules measured less than one cm (microcarcinoma). In the initial surgical procedure, 13 patients had lymph node metastases, 2 of them had a primary tumor of 1 cm and 5 patients had Graves’s Disease. Frozen biopsies during operation had 9 false negative results for cancer (10.6%). Pathology showed 64 cases of papillary cancer (75%), 14 of follicular (16.5%), two were Hurthle cell cancer (2.4%), three were medullary (3.5%), and two anaplastic (2.4%). Conclusions: in our experience, thyroid cancer is more common in women, solid lesions predominate in the ultrasonography and calcifications are frequently found. The tumor size is variable and the most frequent pathological type corresponds to differentiated cancers. Using the definitive pathological study as the standard, the diagnostic sensitivity of fine needle cytology was 90.1%, and of frozen section 89.4%. (Rev Méd Chile 2000; 128: 405-10). <![CDATA[El uso de técnicas de biología molecular en los artículos publicados en la Revista Médica de Chile]]> http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0034-98872000000400008&lng=es&nrm=iso&tlng=es Background: Molecular biology is a new branch of biological sciences, with novel laboratory techniques that are being progressively applied into biomedical and clinical research and, furthermore, into medical practice. Aims: To evaluate the use of molecular biology techniques in Chilean biomedical and clinical research and its evolution in the recent decade. Methods: All papers published as research articles, clinical experiences or case reports, in Revista Médica de Chile, during two time periods: 1987-1989 and 1997-1999, were reviewed to find out whether molecular biology techniques had been used or not. This journal publishes roughly 40% of papers generated in Chile, in biomedical or clinical topics, while another 15% appears in foreign journals. Results: Among 341 papers published in 1987-1989, 57 (16.7%) had used one or more molecular biology techniques; in contrast, among 318 papers published in 1997-1999, 91 (28.8%) had used them (p<0.001). Most papers using molecular biology techniques were research articles. Immunology, genetics, endocrinology, hematology, hepatology and rheumatology were the specialties providing a greater number and proportion of papers using molecular biology techniques. Chilean universities were the main institutions sponsoring these articles and FONDECYT (the Chilean Government Research Granting Office) was the main source of funding. The University of Chile (State-owned) provided most centers where these publications had been generated, followed by the Pontifical Catholic University of Chile. Conclusions: Molecular biology techniques have been rapidly and progressively incorporated as research tools in biomedicine and clinical medicine, in Chile. At the present time, these techniques are predominantly used in research conducted in University settings and funded by Governmental research grants. (Rev Méd Chile 2000;128: 411-18). <![CDATA[Detección y caracterización por ultrasonido de cuerpos extraños de partes blandas]]> http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0034-98872000000400009&lng=es&nrm=iso&tlng=es Background: Soft tissue foreign bodies are a frequent cause of consultation in emergency rooms. It is difficult to verify their existence since conventional radiology only detects radio opaque objects. Ultrasound can be a useful diagnostic procedure. Aim: To report our experience in the detection of soft tissue foreign bodies by ultrasound examination. Patients and methods: The ultrasonographic appearance of vegetables, glass and plastic, metal, bone and stones was studied in gelatin preparations. In a second stage, 52 patients (27 male, aged 3 to 88 years old) were studied, in whom the presence of a soft tissue foreign body was confirmed surgically. Results: The mean error of the procedure for the assessment of foreign body size was 0.2 mm in vitro and 0.5 mm in vivo. The deepness and involved planes were correctly diagnosed in 96%, the number of fragments were diagnosed correctly in 94% of cases. The type of foreign body was identified correctly in 77% of cases and complications were detected in 100% of cases. Conclusions: Ultrasound is a sensitive and accurate method for the detection of soft tissue foreign bodies. (Rev Méd Chile 2000; 128: 419-424). <![CDATA[Apnea severa: signo precoz de neumonía por <I>Pneumocystis carinii</I> en un lactante VIH negativo]]> http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0034-98872000000400010&lng=es&nrm=iso&tlng=es A few reports in the medical literature suggest an association between Pneumocystis caring and apnea in small infants. This patient, a 1 month 20 days old, HIV negative, infant girl weighing 2,000 grams was admitted to hospital after presenting a severe episode of apnea with cyanosis and bradicardia. She progressively developed bronchopneumonia by P. carinii that required prolonged mechanical ventilation with high ventilatory parameters. The clinical course of this patient illustrates that apnea can be an early sign of P. carinii infection in small infants. Early diagnosis and specific therapy might prevent morbidity and mortality and also decrease the length of hospitalization. (Rev Méd Chile 2000; 128: 425-429). <![CDATA[Distribución de los recursos financieros de acuerdo con la productividad (determinada por bibliometría) en los Laboratorios de Investigación Médica del Hospital de Clínicas, de la Facultad de Medicina de la Universidad de San Pablo (Brasil)]]> http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0034-98872000000400011&lng=es&nrm=iso&tlng=es A challenge that research managers have to face is how to "reallocate" agency budgets in order to bring them in line with the results of performance reviews. Research policies must develop a strategic plan describing their goals, devise yardsticks to measure their progress, and tie that performance to allocate research funds with some degree of priority. Though Brazil already has a substantial presence in world’s science, scientific enterprise must be used to strengthen it. The first step should be to raise standards in Brazilian science by concentrating the resources on supporting excellence. A strategy to judge biomedical research productivity should include tactics to disclose whether the resulting publications have appeared in the field’s most respected, peer-reviewed journals. A pilot project to road-test the above-discussed ideas on performance measurements was conducted at the Laboratories of Medical Research (Clinical Hospital, University of São Paulo School of Medicine). These Laboratories perform a vast proportion of biomedical research at the country’s largest University. This article illustrates that confidence in fairness and consistency with which funds are now being allocated has helped to improve productivity, thus showing that this strategy is fruitful. (Rev Méd Chile 2000; 128: 431-6). <![CDATA[Nutrición molecular, papel del sistema PPAR en el metabolismo lipídico y su importancia en obesidad y diabetes mellitus: <I>regulation of lipid metabolism by peroxisome proliferator activated receptors (PPAR). Their relatioship to obesity and diabetes mellitus</I>]]> http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0034-98872000000400012&lng=es&nrm=iso&tlng=es PPARs are transcription factors belonging to the super family of hormonal receptors. Their activity is regulated by fibrates, thiazolidinediones, certain anti inflammatory drugs and fatty acid derivatives, present in food. PPAR isoforms play a central role in lipid homeostasis, regulating anabolic (PPARg) and catabolic (PPARa) pathways of lipid metabolism. Additionally, these receptors participate in glucose homeostasis, influence cellular proliferation and differentiation and participate in inflammatory processes. The effects of PPARs on oxidative substrate partitioning suggests that they have a relevant role in the development of obesity and insulin resistance. (Rev Méd Chile 2000; 128: 437-46). <![CDATA[Susceptibilidad a la infección por virus varicela-zoster, en embarazadas adolescentes del área norte de Santiago]]> http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0034-98872000000400013&lng=es&nrm=iso&tlng=es PPARs are transcription factors belonging to the super family of hormonal receptors. Their activity is regulated by fibrates, thiazolidinediones, certain anti inflammatory drugs and fatty acid derivatives, present in food. PPAR isoforms play a central role in lipid homeostasis, regulating anabolic (PPARg) and catabolic (PPARa) pathways of lipid metabolism. Additionally, these receptors participate in glucose homeostasis, influence cellular proliferation and differentiation and participate in inflammatory processes. The effects of PPARs on oxidative substrate partitioning suggests that they have a relevant role in the development of obesity and insulin resistance. (Rev Méd Chile 2000; 128: 437-46). http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0034-98872000000400014&lng=es&nrm=iso&tlng=es <![CDATA[XXI Congreso Chileno de Medicina Interna, 1999: Resúmenes de Trabajos Libres]]> http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0034-98872000000400015&lng=es&nrm=iso&tlng=es PPARs are transcription factors belonging to the super family of hormonal receptors. Their activity is regulated by fibrates, thiazolidinediones, certain anti inflammatory drugs and fatty acid derivatives, present in food. PPAR isoforms play a central role in lipid homeostasis, regulating anabolic (PPARg) and catabolic (PPARa) pathways of lipid metabolism. Additionally, these receptors participate in glucose homeostasis, influence cellular proliferation and differentiation and participate in inflammatory processes. The effects of PPARs on oxidative substrate partitioning suggests that they have a relevant role in the development of obesity and insulin resistance. (Rev Méd Chile 2000; 128: 437-46).