Residue depletion of oxytetracycline (OTC) and 4-epi-oxytetracycline (4-epi-OTC) in broiler chicken's claws by liquid chromatography-tandem mass spectrometry (LC-MS/MS).

Antibiotics are widely used in poultry production for the treatment of bacterial diseases. However, residues may remain in products and by-products destined for human consumption or animal feeding. The claws of chickens, which are a by-product of the poultry industry, can directly or indirectly enter the food chain as meals destined to feed other productive animals. Thus, it becomes necessary to determine and quantify antimicrobial residues present in this matrix. The objective of the study was to assess the depletion of oxytetracycline (OTC) and its metabolite 4-epi-OTC in broiler chicken's claws. Claws of 32 broilers treated with a therapeutic dosage of 10% OTC during 7 days were analysed. Samples were taken at days 3, 9, 15 and 19 post-treatment. As for the control group, eight broiler chickens were raised under the same conditions. Extraction was carried out through EDTA-McIlvaine buffer, and clean-up employed a SPE C-18 Sep-Pak®. Instrumental analysis was performed through LC-MS/MS. The concentrations of both analytes were determined in claw samples until day 19 post-treatment. Average concentrations were within the LOD (20 µg kg-1) and LOQ (22 µg kg-1) for OTC and 84 µg kg-1 for 4-epi-OTC. Withdrawal times (WDTs) of 39 days for OTC and 54 days for 4-epi-OTC were established in claws based on 95% confidence. These findings demonstrate that claws can be a source of antimicrobial residue entry into the food chain, since the results showed that OTC and its metabolite can be found in chicken's claws for long periods, even exceeding the average lifespan of a broiler chicken.

Rash y anemia aplásica inducidos por fenitoína: caso clínico / Phenytoin-induced rash and aplastic anemia: case report

Rash is a common side effect associated with antiepileptic drugs. The rate of a phenytoin rash is 5.9 percent and increases to 25 percent in those with another antiepileptic drug rash. Aplastic anemia is an adquired hematopoietic stem-cell disorder characterized by pancytopenia of the peripheral blood and hypocellular bone marrow. The use of phenytoin is associated with a 3.5 fold increased risk of aplastic anemia. We report a case of a 70-year-old woman who developed two severe adverse reactions simultaneously with phenytoin: a maculopapular pruritic rash with involvement of mucous and an aplastic anemia. Both conditions normalized after phenytoin withdrawal.

El rash es un efecto secundario común asociado al uso de fármacos antiepilépticos. La frecuencia de rash con fenitoína se ha estimado en un 5,9 por ciento y asciende a un 25 por ciento en pacientes que han presentado rash con otro fármaco antiepiléptico. La anemia aplásica es una anomalía adquirida de las células madre hematopoyéticas caracterizada por pancitopenia de la sangre periférica y médula ósea hipocelular. Los pacientes tratados con fenitoína presentan un riesgo 3,5 veces mayor de desarrollar anemia aplásica. Presentamos el caso de una mujer de 70 años que desarrolló dos reacciones adversas severas y simultáneas a la fenitoína: un exantema maculopapular pruriginoso con compromiso de mucosas y una anemia aplásica. Ambas condiciones se resolvieron completamente con la suspensión del fármaco.

[Evaluation of children with tuberculosis contact]. / Estudio del niñio en contacto con paciente tuberculoso.

Tuberculosis (TB) is a worldwide infectious disease, caused by Mycobacterium tuberculosis (Koch bacilli), that has re-emerged since the decade of the 80's in relation to the pandemic of HIV infection. Chile has one of the lowest TB prevalence rates in Latin America. In children, TB exhibits some differences from adult disease in terms of pathogenesis, clinical manifestations and probability of progression from the infected state to disease, making it more difficult to diagnose and increasing the likelihood of developing the disease once the infection is acquired. There is a National Program for the Prevention and Control of TB that allows us to develop prevention and chemoprophylaxis strategies. This article summarizes these strategies to guide the study and management of children in contact with TB patients.

Estudio del niño en contacto con paciente tuberculoso / Evaluation of children with tuberculosis contact

La tuberculosis (TBC) es una enfermedad de distribución mundial, producida por Mycobacterium tuberculosis (bacilo de Koch), que ha re-emergido desde la década de los 80 en relación a la pandemia de VIH. Chile es uno de los países latinoamericanos con menores tasas de prevalencia de TBC. En los niños, la TBC presenta algunas características distintas al adulto en cuanto a patogenia, clínica y probabilidad de progresión desde una infección latente a enfermedad, siendo más difícil realizar el diagnóstico y mayor la probabilidad de desarrollar enfermedad una vez infectados. Existe un Programa Nacional de Prevención y Control de la TBC que nos permite plantear estrategias de prevención y quimioprofilaxis. Este artículo esquematiza estas estrategias para orientar el estudio y manejo de niños que entran en contacto con pacientes con TBC.

Tuberculosis (TB) is a worldwide infectious disease, caused by Mycobacterium tuberculosis (Koch bacilli), that has re-emerged since the decade of the 80’s in relation to the pandemic of HIV infection. Chile has one of the lowest TB prevalence rates in Latin America. In children, TB exhibits some differences from adult disease in terms of pathogenesis, clinical manifestations and probability of progression from the infected state to disease, making it more difficult to diagnose and increasing the likelihood of developing the disease once the infection is acquired. There is a National Program for the Prevention and Control of TB that allows us to develop prevention and chemoprophylaxis strategies. This article summarizes these strategies to guide the study and management of children in contact with TB patients.

Manejo del accidente cerebro-vascular isquémico agudo / Acute ischemic stroke therapy

El infarto cerebral es una patología con gran impacto en la salud pública de nuestro país. Al ocluirse el flujo sanguíneo de una arteria cerebral se produce una cascada de eventos moleculares que llevan al daño neuronal. En esta condición, queda un tejido con circulación limítrofe alrededor del infarto, la llamada penumbra isquémica, que es potencialmente recuperable, sólo si se produce rápidamente la reperfusión. La recanalización precoz del vaso ocluído es la terapia más efectiva en el infarto cerebral agudo. En la última década ha habido importantes avances en el manejo de esta patología. Estudios de gran escala han mostrado el beneficio de la trombolisis intravenosa administrada en las primeras tres horas del inicio de los síntomas, el beneficio de la trombolisis intraarterial en las primeras seis horas, el uso de antiplaquetarios en las 48 horas iniciales y la importancia del adecuado manejo de las condiciones médicas asociadas, en unidades especializadas (“stroke unit”), para mejorar el desenlace. Las estrategias actuales se orientan a expandir la ventana terapéutica por sobre las tres horas clásicas y evaluar maniobras que tengan más beneficios en los pacientes de mayor gravedad. El propósito de este artículo es revisar, algunas de estas terapias que parecen más promisorias.

Stroke has a major impact on the public health of our nation. When focal occlusions disrupt blood flow to the brain, a cascade of molecular events ensues that produces cell injury. Tissues with borderline cerebral blood flow comprise the ischemic penumbra, areas of stunned parenchyma surrounding the ischemic core, which have potential for recovery, but only if reperfusion is rapidly established. Early re-canalization of an occluded artery is the most effective treatment for this condition. Over the last decade there have been rapid advances in the management of patients with acute ischemic stroke. Large-scale trials have demonstrated beneficial effects of intravenous thrombolytic treatment delivered within 3 hours of symptom onset, intra-arterial thrombolytic therapy within 6 hour of symptom onset, antiplatelet therapy within 48 hours of symptom onset and other studies have suggested that the supportive medical measures undertaken in Stroke Units also improve patient outcomes. Novel therapeutic strategies are seeking to expand the therapeutic time window to > 3 hours and to more effectively treat patients with a severe infarction. The purpose of this article is to review some of the current therapies for acute ischemic stroke.

Utilidad diagnóstica de un cuestionario de sueño y de la escala de somnolencia de Epworth en el síndrome de apneas/hipopneas obstructivas del sueño (SAHOS) / The usefulness of a sleep questionnaire and the epworth sleep scale in the diagnosis of obstructive sleep apnea syndrome (OSAS)

Introduction: Obstructive sleep apnea syndrome (OSAS) is a common disease associated with significant morbidity, including excessive daytime sleepiness, cardiovascular disease and stroke. Method: We studied prospectively the patients sent to our sleep laboratory for polysomnography (PSG) during 6 months. One-hundred patients were interviewed with a sleep questionnaire, 3 of them were ruled out because the lacking of PSG and 2 who no completed the Epworth sleep scale (ESS). Results: Out of the 95 patients, there were 85 men and 10 women, with a mean age of 47.4 +/- 12.5 years, obesity was found in 42.5 percent, an ESS greater than 11 points was found in 56.8 percent, loud snoring in 93.7 percent, breathing cessation in 68.4 percent, excessive daytime somnolence in 57.9 percent. PSG revealed no OSAS in 14.7 percent, slight OSAS in 27.4 percent, moderate OSAS in 21 percent y severe OSAS in 36.8 percent. Body mass index and breathing cessation reported by the couple had the highest discriminative power with a sensibility of 87 percent and specificity of 50 percent for ruled out severe OSAS. Conclusion: A severe OSAS is less probable when there is absence of breathing cessation during sleep reported by the couple and an IMC <30 Kg/m².

Introducción: El SAHOS presenta una alta prevalencia en estudios internacionales, con importantes repercusiones en los sistemas cardio, cerebrovascular y en la calidad de vida de las personas. Método: Estudiamos prospectivamente a los pacientes enviados para Polisomnografia (PSG) a nuestro laboratorio de sueño, en un período de 6 meses. Previo consentimiento informado, se les aplicó la Escala de Somnolencia de Epworth (EE) y un Cuestionario de Sueño. Fueron entrevistados 100 pacientes, excluyéndose 3 por no haberse realizado PSG y 2 que no completaron la EE. Resultados: Se analizaron 95 pacientes, 89,5 por ciento hombres, edad promedio 47,4 +/- 12,5 años, obesidad en 49,5 por ciento, EE mayor de 11 en 56,8 por ciento, ronquido en 93,7 por ciento, pausas respiratorias en 68,4 por ciento, somnolencia diurna excesiva en 57,9 por ciento, cansancio al despertar en 86,3 por ciento. La PSG no demostró SAHOS en 14,7 por ciento, hubo 27,4 por ciento con SAHOS leve, 21 por ciento> moderado y 36,8 por ciento> severo. Las variables presencia de pausas respiratorias observadas por la pareja e índice de masa corporal (IMC) predicen la ausencia de SAHOS severo, con una sensibilidad de 87 por ciento y especificidad de 50 por ciento. Conclusión: En la evaluación de pacientes con sospecha de SAHOS, la no observación de pausas respiratorias durante el sueño por parte de la pareja y el IMC menor de 30 Kg/m² hacen menos probable que exista un SAHOS severo.

Aplicación de un cuestionario de sueño y la escala de somnolencia de Epworth en un centro de salud familiar / Application of a sleep questionnaire and the Epworth sleepiness scale in a family health center

Introduction: Sleep disorders, especially sleep breathing disorders, have not been well studied in the patients attending a family health center in Chile. Sleep breathing disorders have been linked to cardiovascular and cerebrovascular diseases, which are important causes of morbidity and mortality. Method: We studied a randomized sample of 180 adult patients (135 women and 45 men, with a mean age of 45.6 years) consulting a public family health center with the Epworth Sleepiness Scale and a Sleep Questionnaire which include assessment of obesity medical conditions, medications and smoking habit, blood pressure, sleep habits, snoring, breathing cessation, insomnia, daytime sleepiness and depressive symptomatology Results: Hypertension was found in 37.2 percent, diabetes in 11.1 percent, dislipidemia in 19.4 percent, smoking in 34.4 percent. Body mass index > of30 Kg/m2 was found in 38.3 percent). Twenty five patients (13.9 percent>) had an Epworth score >ofl5. Loud snoring was reported in 56.7 percent>. Breathing cessation was reported by the spouses in 21.7 percent>. Difficulty for sleep initiation was present in 21.7 percent and to maintain sleep in 21.7 percent. Daytime sleepiness was present in 29.4 percent. Twelve patients (6.7 percent) had the highest score in a visual analog scale for daytime somnolence. An affirmative answer for persistent sadness or low mood and loss of interest or pleasure in the last month was reported by 43.8 percent of the patients. Conclusion: It is noteworthy the high frequency of undiagnosed sleep disorders found in a population consulting by others pathologies. These results would be useful for the planning of public health programs which should include sleep disorders.

Introducción: Los trastornos del sueño, especialmente el Síndrome de Apneas del Sueño (SAS), presentan una alta prevalencia internacional, pero no existen estudios en Chile. Método: Durante un período de 6 meses, se ingresó progresivamente una muestra randomizada de 180 pacientes mayores de 18 años (135 mujeres, 45 hombres) que consultaron en un Centro de Salud Familiar, para evaluar la frecuencia de trastornos de sueño con la Escala de Somnolencia de Epworth y un Cuestionario de Sueño especialmente diseñado que incluyó: estado nutricional, enfermedades médicas, uso de medicamentos, tabaco y alcohol, hábitos de sueño, ronquido, pausas respiratorias, insomnio, somnolencia diurna excesiva y síntomas depresivos. Resultados: Se encontró hipertensión arterial en 37,2 por ciento, diabetes en 11,1 por ciento, dislipidemia en 19,4 por ciento y tabaquismo en 34,4 por ciento, IMC > de 30 kg/m2 en 38,3 por ciento, Epworth > 15 en 13,9 por ciento, ronquido en 56,7 por ciento, pausas respiratorias en 21,7 por ciento, somnolencia diurna excesiva en 29,4 por ciento, dificultad en la iniciación (21,7 por ciento) y mantención del sueño (21,7 por ciento). Tristeza persistente y/o pérdida de interés en sus actividades o falta de disfrute en el último mes fue referida por 43,8 por ciento de los pacientes. Conclusión: La alta frecuencia de trastornos del sueño encontrados, hacen necesario incluirlos en la planificación de programas de salud en nuestro país, para su adecuado diagnóstico y tratamiento, especialmente considerando el que algunos de estos trastornos constituyen factores de riesgo para enfermedades vasculares cardíacas y cerebrales.

Ovine Echinococcus granulosus transmission dynamics in the province of Rio Negro, Argentina, 1980-1999.

In this work, the impact of a hydatidosis control programme for dogs on the intermediate ovine host was specifically analysed to determine the levels of prevalence achieved and the dynamics of parasite transmission, as well as to evaluate the quality of diagnostic systems in slaughterhouses. A field study was conducted in four slaughterhouses (Valcheta, Los Menucos, Jacobacci, Bariloche) that process animals coming from all the departments within the work area. The control programme for dogs entailed treating dogs with 5 mg/kg praziquantel at 2-month intervals for 20 years. Sample size was determined with a 10% error margin and a 95% significance level. Harvested viscera (liver, lungs, kidneys) were preserved in 5% formaldehyde and sent to the laboratory for diagnostic confirmation of both positive and negative specimens. The 61% initial prevalence dropped to 18.3% at the end of the 10-year period, observed differences proving significant (Chi-square=15.454, P=0.00). There were statistically significant increases in infection prevalence with age (Pearson's Chi-square=133.61, P=0.00). Overall, 37.2% of hydatidosis cases diagnosed in slaughterhouses were considered non-hydatid by histological study. On the other hand, 1.1% of those diagnosed as healthy were found to be infected with hydatidosis. The number of hydatid cysts per animal increased with age: 0.04 in lambs and 1.22 in adults (linear regression equation, -0.0539+0.0127 x age), whereas the average for the whole period was 3.7% in lambs and 20.5% in adults. Viability studies indicated that 63.8% of parasitised animals had viable cysts, out of which 53.3% were fertile. Diagnosis of infection in sheep made by means of an adjusted statistical design and with histological confirmation of the presumptive diagnosis made in slaughterhouses demonstrated the flaws of the official systems for epidemic surveillance of hydatidosis. However, there was no overall significant difference in slaughterhouse and laboratory data.Ro was 0.53 and could imply a decrease in reproductive capacity of the parasite and steady state extinction.

Síndrome de piernas inquietas: estudi clínico en población general adulta y en pacientes urémicos / Restless legs syndrome: a clinical study in chilean general population and in uremic patients

Background: The restless legs syndrome (RLS) is a movement disorder characterized by an imperative urge to move the legs, associated with paraesthesias, motor restlessness and worsening of symptoms at night with at least partial relief by activity. Its prevalence ranges between 2-15 percent of general adult population and 20-30 percent of uremic patients. Aim: To evaluate the frecuency and the clinical features of RLS in a sample of general adult population and in uremic patients, in Chile, correlating it with biochemical parameters. Method: 100 relatives of outpatients and 166 uremic patients undergoing chronic haemodialysis were interviewed assessing the presence and severity of RLS according to current diagnostic criteria. Biochemical parameters assessed were hematocrit, serum ferritin, phosphate, intact parathyroid hormone (iPTH) levels. Results: 13 percent of the general population sample was affected, 15 percent of them were severe. Forty three cases were found among uremic patients (25.9 percent) (p <0.01 vs general population), 60 percent of them were severe and women were affected with higher frequency (p <0.05) and severity (p <0.01). Four patients presented RLS even during hemodialysis. No correlation was found with biochemical parameters. Most RLS cases had not been diagnosed previously. Conclusions: In our population RLS is common and undetected. It is especially prevalent and severe in uremic patients: we found no evidence that anaemia, iron deficiency or iPTH level play a major pathogenic role. Our findings emphasize the need of greater medical awareness of RLS because available therapy may improve the quality of life

Rate of infection and of reinfection by Echinococcus granulosus in rural dogs of the province of Rio Negro, Argentina.

Hydatidosis (cystic echinococcosis) constitutes a serious public health problem in the Province of Rio Negro, Argentina. In the present work it was intended to evaluate the prevalence of the canine echinococcosis in rural areas of the Province of Rio Negro and studied the reinfection rate in dogs after treatment with Praziquantel during the period 1980-1997. A total of 496 dogs were studied in 18 canine concentrations in order to establish the initial prevalence rate which was 42.3%. From 1980 onward dogs should have been systematically treated with anthelmintic every 2 months in rural areas and every 6 months in urban areas. We estimated that approximately 65% of dogs were treated. To determine the reinfection rate, 476 dogs (1984) and 598 dogs (1996) were studied after anthelmintic treatment during two sequential time periods (0-45; 46-90 days). In both cases treated animals were compared with untreated dogs. Prevalences were 3.5%, 6.7% and 21.3% in 1984 and 0.8%, 4.0% and 10.0% in 1996. For the purpose of surveillance a total number of 21,444 dogs were studied during 18 years. Prevalence of Echinococcus granulosus decreased significantly in the first year from 42.3% to 6.1%.

Activador del plasminógeno tisular intravenoso en el tratamiento del infarto cerebral agudo: factibilidad, seguridad y eficacia en los primeros dos años de práctica clínica / Intravenous tissue plasminogen activator in acute ischemic stroke: feasibility, safety and efficacy in the first 2 years of clinic practice

Background: The only effective therapy for the treatment of acute ischemic stroke is the infusion of tissue plasminogen activator in the first three hours after the onset of symptoms. Aim: To report the experience with tissue plasminogen activator infusion in the treatment of acute ischemic stroke. Patients and methods: Ten males and 10 females, aged 52 to 85 years old with an acute ischemic stroke, admitted within 89 min after the onset of symptoms were studied. Tissue plasminogen activator was infused following the guidelines designed by the National Institute of Neurological Disorders and Stroke (NINDS). Patients were assessed according to Rankin scale after three months of follow up. Results: All patients had normal CAT scans. The delay between the onset of symptoms and the infusion ranged from 75 to 180 min. One patient had a gastrointestinal bleeding due to a gastric ulcer and one patient had a fatal intracranial hemorrhage. After three months of follow up, 38 percent of patients had a good recuperation (Rankin 0 to 1), 33 percent had a mild to moderate disability (Rankin 2 or 3) and 14 percent had a moderate to severe disability (Rankin 4). There was a 15 percent mortality. Conclusions: This series show that treatment of acute ischemic stroke with tissue plasminogen activator is feasible and safe. The obtained results are similar to those reported abroad

Hemorragias cerebrales y angiopatía amiloidea / Cerebral amyloid angiopathy in brains of patients dying of non traumatic cerebral hemorrhages

Background: Cerebral amyloid angiopathy is considered pathogenic in non traumatic cerebral lobar hemorrhages. Aim: To study the frequency of cerebral amyloid angiopathy in brains of patients dying of non traumatic cerebral hemorrhages. Material and methods: Thirty seven brains from patients, 25 men and aged 65ñ10 years old, with cerebral hemorrhages (14 lobar, 18 in basal ganglia and 5 in cerebellum or brainstem) were studied. As controls, the brains of 30 subjects, 14 men and aged 64ñ16 years old, dying of non neurological causes were studied. Deep and cortical vessels were stained with hematoxylin eosin, Gomori, Thioflavin T and Bodian. Definitive cerebral amyloid angiopathy was diagnosed when amyloid deposition was observed in the media of vessels. Results: Twenty six out of 32 patients dying of cerebral hemorrhage and 3 of 21 controls had chronic hypertension. Cerebral amyloid angiopathy was present in 19 of 37 brains of patients with cerebral hemorrhage and 13 of 30 control brains. In patients with hypertension, vascular changes independent of the location and volume of amyloid deposition, were observed. Such changes were dilatation, tortuousness, thickening of walls specially in muscular and adventitia and hyaline degeneration. Thirteen brains with hemorrhage had fibrinoid necrosis and 10 had microaneurysms. Conclusions: In this series of patients, cerebral amyloid deposition was unspecific and its role in the pathogenesis of cerebral hemorrhages was not confirmed. Hypertension was associated with vascular degenerative changes that can lead to cerebral hemorrhages

Neuromielitis óptica: una enfermedad necrotizante del sistema nervioso central / Optic neuromyelitis: a necrotizing disease of the central nervous system

Optic neuromyelitis is characterized by simultaneous or successive necrotizing lesions involving the optic nerves and the spinal cord. We report two females with the disease, aged 30 and 34 years old. In the latter, a neuropathological study was done. Both patients had clinical, neuroradiological and pathological features that differed from those of primary demyelinating syndromes such as multiple sclerosis. These patients illustrate the selectivity of optic nerve and spinal cord lesions. The latter involve mainly pyramidal and Goll tracts while, within the necrotizing lesions of the optic chiasma, the fibers of the unaffected optic nerve are spared. This pattern suggests a selective injury to some population of axons. Blood vessels were not affected in the necrotizing areas and the lesions did not follow a vascular territory, therefore a vascular mechanism causing the disease is unlikely. The clinical and neuropathological features of neuromyelitis optic suggest a selective involvement of some axons

Estudio de ingesta y niveles séricos de cobre como factor de riesgo de enfermedad ateromatosa / Copper intake and blood levels as risk factor for atherosclerosis

Zinc and copper intake, plasma levels and serum lipid levels were measured in 20 patients with cerebrovascular disease, 20 patients with an acute myocardial infarction and 40 subjects hospitalized for elective surgery, that served as controls. Results: Copper and zinc intake was below recommended allowances in all subjects. Serum zinc and copper levels did not differ in the three study groups. In patients with myocardial infarction a weak correlation was found between serum copper and total cholesterol (r = 0.24; p < 0.05) and LDL cholesterol (r = 0.31; p < 0.05). Conclusions: No differences in copper levels were found in subjects with atherosclerosis and controls. The correlation between serum copper and cholesterol deserves further investigation

Crisis isquémicas transitorias en Chile y su relación con el patrón de enfermedad cerebrovascular chileno / Transient ischemic attacks in Chile and it relation with chilean cerebrovascular disease standard

Patients and methods: One hundred forty nine patientes admitted to a Neurology service of a public hospital in Santiago, with an acute stroke, were studied. Patients and close relatives were interrogated about previous symptoms of TIA using a structured questionnaire. Results: One hundred nine patients had an ischemic and 40 patients a hemorrhagic stroke. Twenty patients with ischemic stroke had a history of TIA (18 percent). Fifteen out of 74 patients without a cardiac source of emboli (20 percent) and five out of 354 cases with an embolic source (14 percent) had a TIA preceding their stroke. Three out of 40 patients (8 percent) with hemorrhagic stroke had a history of TIA. Conclusions: This study does not support nor reject the hypothesis of a Chilean pattern of cerebrovascular disease unlike that found in Northern Caucasians

Potenciales evocados somatosensoriales y respuesta sintomática a medicamentos dopaminérgicos en enfermedad de Parkinson / Somatosensory evoked potentials and sintomatic response to dopaminergic drugs in Parkinson's disease

Short latency somatosensory evoked potentials were measured in 10 patients with Parkinson's disease before and after tha administration of Apomorphine 5 mg sc. Eight of these subjects were reassessed after one month of treatment with Levo-dopa. These potentials were measured in other nine subjects before and after one month of treatment with Selegiline 10 mg od. There was a significant increase of frontal potential N30 in nine of 10 subjects that received apomorphine, in seven of 8 patients treated with Levodopa and 7 of 9 patients treated with Selegiline. No changes in N20 parietal potential were observed. During apomorphine test, changes in N30 potential preceded clinical improvement in 6 patients and occurred simultaneously in 3 patients. No changes with apomorphine in N30 potential were observed in 2 healthy males. There was no relationship between electrophysiological changes and duration of disease or motor fluctuations. It is concluded that short latency somatosensory evoked potentials are an objective means of measuring dopaminergic response in patients with Parkinson's disease

Validación de un instrumento de tamizaje para el estudio de la prevalencia de enfermedades cerebrovasculares en la población chilena / Assessment of a screening instrument to study the prevalence of cerebrovascular diseases in the chilean population

We assessed a screening instrument, adapted from a model suggested by WHO, aimed to perform population studies on the prevalence of cerebrovascular disease in Chile. Sixty-two subjects, 31 with cerebrovascular diseases and 31 without, were asked about symptoms and requested to do simple movements by trained interviewers. The results of the instrument were compared with a neurological examination performed by two specialists. Global sensitivity and specificity of the instrument, using WHO evaluation criteria, were 100 and 38.7 percent respectively. When three or more symptoms and one positive sign were considered as cutoff points, global specificity increased to 61 percent and sensitivity decreased to 93 percent. It is concluded that the present instrument is highly sensitive but lacks specificity