Scielo RSS <![CDATA[Revista médica de Chile]]> https://scielo.conicyt.cl/rss.php?pid=0034-988720000008&lang=pt vol. 128 num. 8 lang. pt <![CDATA[SciELO Logo]]> https://scielo.conicyt.cl/img/en/fbpelogp.gif https://scielo.conicyt.cl <![CDATA[<I>Neuropeptide Y contribution to the physiology of human sympathetic co transmission.</I>: <I>Studies in saphenous vein biopsies</I>]]> https://scielo.conicyt.cl/scielo.php?script=sci_arttext&pid=S0034-98872000000800001&lng=pt&nrm=iso&tlng=pt Background: It is known that the sympathetic varicosities co-store and co-release norepinephrine (NE) together with adenosine S-triphosphate (ATP) and neuropeptide Y (NPY). Aim: To describe the chemical characterisation of stored and released NPY from the varicosities of sympathetic nerve terminals surrounding segments of the human saphenous vein, and the vasomotor activity of rings electrically depolarized or contracted by the exogenous application of the co-transmitters. Material and methods: Saphenous vein tissues were obtained from patients undergoing elective cardiac revascularization surgery. Results: The chromatographic profile of NPY extracted from biopsies is identical to a chemical standard of human NPY. Upon electrical depolarisation of the perivascular sympathetic nerve terminals, we demonstrated the release of NPY to the superfusion media, which did not exceed a 1% of its stored content. The release of the peptide is sensitive to guanethidine, and to extracellular calcium, suggesting that the mechanism of its release is exocytotic in nature. The electrically evoked release of NPY is dependent on the frequency and duration of the electrical pulses. Phenoxybenzamine reduces the electrically evoked release of NPY. Exogenous application of NE and ATP contract saphenous vein rings; the simultaneous application of NE plus ATP causes a synergic response, effect which is further potentiated by the joint co-application of 10 nM NPY. Conclusions: Present results highlight the role of NPY as a sympathetic co-transmitter in the regulation of human vascular tone. (Rev Méd Chile 2000; 128: 829-38). <![CDATA[<I>Impact of antiretroviral therapy in mortality of Chilean HIV (+) patients</I>: <I>a case-control study</I>]]> https://scielo.conicyt.cl/scielo.php?script=sci_arttext&pid=S0034-98872000000800002&lng=pt&nrm=iso&tlng=pt Background: Combined antiretroviral therapy (AVR) has shown a protective effect (PE) on morbidity and survival in HIV (+) patients of industrialised countries where triple-drug therapy (ARV-3) is standard. In Chile the public health system began providing double-drug therapy in 1997 (ARV-2) with 2 reverse transcriptase inhibitors. Aim: To assess the impact of ARV in morbimortality of HIV (+) patients in Chile after a year of follow up. Patients and methods: Retrospective case-control (1:1) study. Cases were 97 patients followed during 1997 for 6 or more months and dying during that period. Each case had a control of the same gender and CDC stage, similar age and CD4 count, but surviving a same period of follow up. A comparison of ARV before and during follow up (rate and type) was done. P carinii prophylaxis, pneumococcal immunization at baseline or follow up, frequency of hospital admissions and occurrence of opportunistic infections in both groups were assessed. Odds ratio (OR) for mortality, hospitalisation and opportunistic infections in ARV user, as well as treatment PE were calculated. Results: Twenty four (24.7%) cases and sixty six (68%) controls received ARV during follow up (p< 0.001), OR was 0.15 (CI 95% 0.08-0.3), p < 0.001, the PE was 6.6 for ARV users versus non users, among cases 19 patients received ARV-2 and five received ARV-3. Among controls, 41 patients received ARV-2 and 25 received ARV-3. These differences established an OR of 0.20 (CI 95% 0.09-0.04) and a PE of 5 for ARV-2 versus no ARV. For ARV-3 compared with no ARV the OR was 0.08 (CI 95% 0.003-0.26), and the PE 12.5. Fifty three (54.6%) cases and 13 (13.4%) controls required hospital admission, OR 0.49 (CI 95% 0.25-0.94), p=0.03, and PE of 2.04 of ARV versus no ARV; 82 (85.3%) cases and 50 (51%) controls had opportunistic infections, OR 0.5 (CI 95% 0.26-0.96), p=0.03 and PE of 2 for ARV versus no ARV. There were no significant differences in prior ARV, prophylaxis and immunisation between cases and controls. Conclusions: This study showed the high impact of ARV in short term morbimortality of HIV(+) patients and the need to implement antiretroviral therapy to all patients as an official health policy. This study did not answer the question of the role, if any, of weaker-than standard antiretroviral therapy. (Rev Méd Chile 2000; 128: 839-45). <![CDATA[<I>Cisapride does not modify prolonged Q-T interval in patients with liver cirrhosis</I>]]> https://scielo.conicyt.cl/scielo.php?script=sci_arttext&pid=S0034-98872000000800003&lng=pt&nrm=iso&tlng=pt Background: Abnormal small bowel motility, observed in liver cirrhosis, can be reversed with cisapride. Since both cisapride and liver disease are associated with prolonged QT interval, the possibility of adverse cardiovascular effects might be expected with cisapride treatment in these patients. Aim: To evaluate QT interval and other electrocardiographic changes during long term treatment with cisapride in cirrhotic patients. Patients and methods: Forty seven cirrhotic patients were studied. Electrocardiogram was recorded and the QT interval corrected according to Bazzett’s formula was determined (normal value <0.44 s). Seventeen patients were treated with cisapride, 10 mg tid for seven months and electrocardiographic controls were performed at the end of the treatment. Results: The mean corrected QT interval was 0.46 ± 0.03 s (range 0.4-0.53). 34 patients (64%) had QTc prolongation (0.47 ± 0,02 s). Statistically significant higher values of QTc were observed in patients at Child Pugh stage B and C compared to stage A. No statistically significant difference according to the etiology of liver disease, were observed. No changes in mean QTc duration were observed during cisapride treatment. Conclusions: In spite that a prolonged QTc was a frequent finding in our serie of selected patients, no cardiovascular adverse effects were observed with long term cisapride treatment. (Rev Méd Chile 2000; 128: 847-52). <![CDATA[<I>Secondary ionizing radiation generated by analog and digital coronary cineangiographic equipment</I>: <I>Influence of external protection devices</I>]]> https://scielo.conicyt.cl/scielo.php?script=sci_arttext&pid=S0034-98872000000800004&lng=pt&nrm=iso&tlng=pt Background: Exposure to ionizing radiation is a known hazard of radiological procedures. Aim: To compare the emission of secondary ionizing radiation from two coronary angiographic equipments, one with digital and the other with analog image generation. To evaluate the effectiveness of external radiological protection devices. Material and methods: Environmental and fluoroscopy generated radiation in the cephalic region of the patient was measured during diagnostic coronary angiographies. Ionizing radiation generated in anterior left oblique projection (ALO) and in anterior right oblique projection (ARO) were measured with and without leaded protections. In 19 patients (group 1), a digital equipment was used and in 21 (group 2), an analog equipment. Results: Header radiation for groups 1 and 2 was 1194 ± 337 and 364 ± 222 µGray/h respectively (p<0.001). During fluoroscopy and with leaded protection generated radiation for groups 1 and 2 was 612 ± 947 and 70 ± 61 µGray/h respectively (p<0.001). For ALO projection, generated radiation for groups 1 and 2 was 105 ± 47 and 71 ± 192 µGray/h respectively (p<0.001). During filming the radiation for ALO projection for groups 1 and 2 was 7252 ± 9569 and 1671 ± 2038 µGray/h respectively (p = 0.03). Out of the protection zone, registered radiation during fluoroscopy for groups 1 and 2 was 2800 ± 1741 and 1318 ± 954 µGray/h respectively (p < 0.001); during filming, the figures were 15500 ± 5840 and 18961 ± 10599 µGray/h respectively (NS). Conclusions: Digital radiological equipment has a lower level of ionizing radiation emission than the analog equipment. (Rev Méd Chile 2000; 128: 853-62). <![CDATA[<I>Presence of integrons and their relationships with the resistance to third generation cephalosporins among nosocomial isolates of Acinetobacter baumannii</I>]]> https://scielo.conicyt.cl/scielo.php?script=sci_arttext&pid=S0034-98872000000800005&lng=pt&nrm=iso&tlng=pt Background: Acinetobacter baumannii is an important etiological agent causing nosocomial infections. High level of resistance for different kind of antimicrobials has been observed, including ß-lactam antibiotics. This feature, chromosomal or plasmid encoded, has been associated to integrons harbouring antibiotic resistance gene cassettes. Aims: To investigate the presence of integrons among clinical isolates resistant to third generation cephalosporins (3GC). Material and methods: One hundred A. baumannii strains isolated from several Chilean hospitals were included in this study. Minimal inhibitory concentrations (MIC) of 3GC by an agar dilution method were carried out. Integrons class 1, 2 and 3 were investigated by colony blot hybridisation and confirmed by PCR. Results: High level of resistance to all assayed 3GC was observed. On the other hand, integrón class 2 was the most prevalent (77% of isolates) followed by integron class 1 (52%). Forty six percent of isolates hybridised with probes for both of them. However, no positive hybridisation was detected for integron class 3. Conclusions: Nevertheless, most isolates harboured one or both class of integron; there was no direct relationship between the presence of these genetic structures and the resistance to this kind of ß-lactam antibiotics. (Rev Méd Chile 2000; 128: 863-7 ). <![CDATA[<I>Treatment of hirsutism with spironolactone and with spironolactone plus dexamethasone</I>]]> https://scielo.conicyt.cl/scielo.php?script=sci_arttext&pid=S0034-98872000000800006&lng=pt&nrm=iso&tlng=pt Background: Spironolactone has an anti androgenic effect, inhibiting the binding of androgens to their receptor. This antagonistic effect is the basis for the use of spironolactone in the treatment of hirsutism. Aim: To study the effectiveness and safety of spironolactone in the treatment of hirsute women and of the association of spironolactone plus dexamethasone in the treatment of hirsutism with glucocorticoid sensitive hyperandrogenism. Patients and method: Sixteen women (group 1) with peripheral hirsutism (defined as those with normal androgens levels, normal menstrual cycles and ovulation) and 24 women (group 2) with glucocorticoid sensitive hyperandrogenic hirsutism were studied. Group 1 was treated with spironolactone 50 mg bid and group 2 with same spironolactone dose plus dexamethasone 0.5 mg at 23 h during one month and 0.25 mg thereafter. Patients were followed during one year. Results: After one year of treatment, a 54% reduction in Moncada hirsutism escore was observed in group 1 and 52% reduction in group 2. Observed secondary effects of spironolactone were increases in diuresis, fatigability, acne aggravation and seborrhea in two patients. Two additional patients had spotting. No secondary effect attributable to glucocorticoid use were observed. Conclusions: Spironolactone is effective and safe in the treatment of hirsutism. Androgenic supression did no increases its effectiveness, underscoring the peripheral anti androgenic activity os spironolactone. (Rev Méd Chile 2000; 128: 868-75). <![CDATA[<I>Salivary gland scintigraphy and lip biopsy in patients with Sjögren syndrome and normal controls</I>]]> https://scielo.conicyt.cl/scielo.php?script=sci_arttext&pid=S0034-98872000000800007&lng=pt&nrm=iso&tlng=pt Background: Salivary gland scintigraphy allows a non invasive, morphological and functional assessment of parotid and submaxillary salivary glands. Aim: To describe the main features of salivary gland scintigraphy in patients with Sjögren syndrome, rheumatic fibromyalgia and normal controls and compare the results with lip biopsy. Patients and methods: Sixty one normal controls, 66 patients with Sjögren syndrome and 18 patients with rheumatic fibromyalgia were studied. For the diagnosis of Sjögren syndrome and fibromyalgia rheumatica, the Modified European and American College of Rheumatology criteria were used, respectively. Lip biopsies were obtained in 52 patients with Sjögren syndrome. Scintigraphy was done with a gamma camera and computer after the administration of 99mTc-pertechnetate, obtaining images during 30 min and creating time/activity curves. Scintigraphy was classified as normal, with mild or severe alterations. Results: Scintigraphy was normal in 74% of control subjects and in 26%, it had mild alterations. In 72% of patients with rheumatic fibromyalgia, scintigraphy was normal whereas in 28%, it had mild alterations. In 27% of patients with Sjögren syndrome, scintigraphy was normal, in 27% it had mild alterations and in 46%, severe alterations. There was a positive and significant correlation between pathological alterations of salivary glands and scintigraphic alterations (r=0.642, p < 0.001). Conclusions: Severe scintigraphic alterations of salivary glands strongly support the diagnosis of Sjögren syndrome. Mild alterations are non specific and a normal scintigraphy does not exclude the diagnosis. (Rev Méd Chile 2000; 128: 877-86 ). <![CDATA[<I>Clinical features of 29 patients with hepatocellular carcinoma</I>]]> https://scielo.conicyt.cl/scielo.php?script=sci_arttext&pid=S0034-98872000000800008&lng=pt&nrm=iso&tlng=pt Background: Hepatocellular carcinoma is the most frequent primary tumor of the liver. It is associated to chronic liver diseases and has a high prevalence in some regions of Africa and Asia. Aim: To describe the clinical characteristics of patients with hepatocellular carcinoma, admitted to two hospitals of the IX region of southern Chile. Material and methods: Prospective study of 29 consecutive patients admitted to two hospitals in Temuco, Chile. Clinical features, laboratory values and viral markers were analyzed. Results: Eighteen patients were male and ages ranged from 29 to 75 years old. The most frequent presenting symptom was abdominal pain in 21 patients. Seven subjects had a history of alcoholism. Serum bilirubin values ranged from 0.1 to 15.8 mg/dl, alkaline phosphatases ranged from 171 to 3476 U/l, ASAT from 24 to 5400 U/l and alpha feto protein from 1.4 to 350 ng/ml. Two patients had a positive hepatitis B surface antigen and all had negative hepatitis C virus antibodies. Mean tumoral diameter was 9.6 cm and the most common presentation was nodular. Mean survival after the diagnosis was 6.3 months. Conclusions: These patients with hepatocellular carcinoma have a low frequency of positive viral markers and tumors of large sizes on presentation. (Rev Méd Chile 2000; 128: 887-95). <![CDATA[<I>Thyroid hemiagenesis associated to Basedow-Graves disease.</I>: <I>Report of one case</I>]]> https://scielo.conicyt.cl/scielo.php?script=sci_arttext&pid=S0034-98872000000800009&lng=pt&nrm=iso&tlng=pt We report a 35 years old female with left lobe thyroid hemiagenesis who initially was euthyroid and then developed hyperthyroidism due to Graves disease. Hemiagenesis of the thyroid gland is a rare anomaly with an uncertain incidence; up to now 256 cases have been reported. The detection is often made by either clinical symptoms of thyroid dysfunction, by imaginological studies or surgical/pathological procedures. No explanation has been given for the development of this anomaly; left lobe aplasia and predominance of occurrence in women have been most frequently reported. (Rev Méd Chile 2000; 128: 896-8). <![CDATA[<I>Pulmonary thromboembolism associated to antiphospholipid syndrome and systemic lupus erythematosus.</I>]]> https://scielo.conicyt.cl/scielo.php?script=sci_arttext&pid=S0034-98872000000800010&lng=pt&nrm=iso&tlng=pt The association between systemic lupus erythematosus and antiphospholipid syndrome can cause several complications. We report a 45 years old woman, treated with steroids for a systemic lupus erythematosus. She presented with a clinical picture of a lupus pneumonitis and, subsequently, with the picture of a pulmonary thromboembolism. The diagnosis was confirmed by helicoidal computed axial tomography. The patient was treated with anticoagulants, with a favourable outcome. (Rev Méd Chile 2000; 128: 899-903) <![CDATA[<I>Patients right, in the frame of medical care quality</I>]]> https://scielo.conicyt.cl/scielo.php?script=sci_arttext&pid=S0034-98872000000800011&lng=pt&nrm=iso&tlng=pt Quality in health care is a patient’s right. This concept has become progressively acknowledged and demanding since it gains relevancy in planning and delivery of medical care. Defining quality -and other factors that condition and modify it- as a value in medical practice, allows the recognition of the important role that this characteristic has in that setting and how significant it is for clinical decision making. Any reduction in the quality of medicine, by distorting bioethical principles, changes it from a desirable good into a fallacy. (Rev Méd Chile 2000; 128: 904-10) <![CDATA[<I>Achievements and challenges of the expanded immunization program in the Americas</I>]]> https://scielo.conicyt.cl/scielo.php?script=sci_arttext&pid=S0034-98872000000800012&lng=pt&nrm=iso&tlng=pt The Expanded Program on Immunization (EPI) was initiated in 1974 in The Americas, based on the WHA 2757 resolution passed by the World Assembly of Health. Its purpose was to improve immunization coverage and to decrease morbidity and mortality caused by vaccine preventable diseases through vaccination. Specific goals were to eradicate in determined time periods poliomyelitis, measles, neonatal tetanus, to eliminate tuberculous meningitis in children four years and younger, diphtheria, and tetanus. This article presents up to date information on vaccination coverage trends between 1990 and 1998 in 13 countries of the American Region, briefly describes implementation of surveillance programs required for appropriate monitoring of vaccine impact, and discusses the changes observed in morbidity attributable to vaccine preventable disease in these countries during four periods, 1968 before the existence of EPI, 1978, four years after its introduction, 1988 and 1998. Although much remains to be done, the impact of EPI in the Americas has been outstanding in decreasing morbidity caused by vaccine preventable diseases. (Rev Méd Chile 2000; 128: 911-22). <![CDATA[<I>Cardiac rehabilitation as a first step in the secondary prevention of coronary heart disease</I>]]> https://scielo.conicyt.cl/scielo.php?script=sci_arttext&pid=S0034-98872000000800013&lng=pt&nrm=iso&tlng=pt Despite that coronary heart disease is still the major cause of death in the industrialized countries and in some with emerging economies, a steady decline in the mortality for coronary heart disease has been observed in the last 30 years. This has been attributed predominantly to a reduction in smoking and in the cholesterol blood levels, two of the major risks factors for coronary heart disease. Cardiac rehabilitation programs represent today one of the most cost effective interventions to reduce the morbidity and mortality after a coronary event. They offer a unique opportunity to guide a patient immediately after an acute coronary episode through the inpatient care to the outpatient environment. In these programs a strong emphasis is made in the educational aspects of secondary prevention of coronary heart disease as well as in motivating patients to achieve life long lasting behavioral changes impacting on the major risk factors (smoking cessation, regular exercise, weight control, etc). The current subutilization of the Cardiac Rehabilitation Programs appears to be related to a variety of factors that include, among others, financial restraints and cultural values and perceptions with reference to health care (Rev Méd Chile 2000; 128: 923-34). <![CDATA[<I>Interim analysis in clinical trials</I>: <I>a methodological guide</I>]]> https://scielo.conicyt.cl/scielo.php?script=sci_arttext&pid=S0034-98872000000800014&lng=pt&nrm=iso&tlng=pt Interim analysis of data accumulated in clinical trials is one aspect of the monitoring of the study progress. It is usually done to assess whether there are significant differences in efficacy between the experimental and control treatment groups, in order to decide whether to stop or no the trial prematurely. Among many reasons for early interruption of a trial is the ethical consideration that subjects should not be exposed to an unsafe, inferior or ineffective treatment. Statistical methods suited for doing interim analysis, that allow to control the probability of incorrectly rejecting the null hypothesis of no treatment differences, are often not well understood by researchers. In this article we present an intuitive, non-mathematical explanation and review of the statistical methods for doing interim analysis in clinical trials along with an illustrative example of the application of the methods on a hypothetical dataset (Rev Méd Chile 2000; 128: 935-41). <![CDATA[<I>Two cases of primary aldosteronism diagnosed in Talca, Chile</I>]]> https://scielo.conicyt.cl/scielo.php?script=sci_arttext&pid=S0034-98872000000800015&lng=pt&nrm=iso&tlng=pt Interim analysis of data accumulated in clinical trials is one aspect of the monitoring of the study progress. It is usually done to assess whether there are significant differences in efficacy between the experimental and control treatment groups, in order to decide whether to stop or no the trial prematurely. Among many reasons for early interruption of a trial is the ethical consideration that subjects should not be exposed to an unsafe, inferior or ineffective treatment. Statistical methods suited for doing interim analysis, that allow to control the probability of incorrectly rejecting the null hypothesis of no treatment differences, are often not well understood by researchers. In this article we present an intuitive, non-mathematical explanation and review of the statistical methods for doing interim analysis in clinical trials along with an illustrative example of the application of the methods on a hypothetical dataset (Rev Méd Chile 2000; 128: 935-41). <![CDATA[Recuerdo del Dr. Oke France Soto]]> https://scielo.conicyt.cl/scielo.php?script=sci_arttext&pid=S0034-98872000000800016&lng=pt&nrm=iso&tlng=pt Interim analysis of data accumulated in clinical trials is one aspect of the monitoring of the study progress. It is usually done to assess whether there are significant differences in efficacy between the experimental and control treatment groups, in order to decide whether to stop or no the trial prematurely. Among many reasons for early interruption of a trial is the ethical consideration that subjects should not be exposed to an unsafe, inferior or ineffective treatment. Statistical methods suited for doing interim analysis, that allow to control the probability of incorrectly rejecting the null hypothesis of no treatment differences, are often not well understood by researchers. In this article we present an intuitive, non-mathematical explanation and review of the statistical methods for doing interim analysis in clinical trials along with an illustrative example of the application of the methods on a hypothetical dataset (Rev Méd Chile 2000; 128: 935-41).