A versatile robotic platform for the design of natural, three-dimensional reaching and grasping tasks in monkeys.

OBJECTIVE: Translational studies on motor control and neurological disorders require detailed monitoring of sensorimotor components of natural limb movements in relevant animal models. However, available experimental tools do not provide a sufficiently rich repertoire of behavioral signals. Here, we developed a robotic platform that enables the monitoring of kinematics, interaction forces, and neurophysiological signals during user-defined upper limb tasks for monkeys. APPROACH: We configured the platform to position instrumented objects in a three-dimensional workspace and provide an interactive dynamic force-field. MAIN RESULTS: We show the relevance of our platform for fundamental and translational studies with three example applications. First, we study the kinematics of natural grasp in response to variable interaction forces. We then show simultaneous and independent encoding of kinematic and forces in single unit intra-cortical recordings from sensorimotor cortical areas. Lastly, we demonstrate the relevance of our platform to develop clinically relevant brain computer interfaces in a kinematically unconstrained motor task. SIGNIFICANCE: Our versatile control structure does not depend on the specific robotic arm used and allows for the design and implementation of a variety of tasks that can support both fundamental and translational studies of motor control.

Litiasis urinaria y su relación con el consumo de aguas duras en la comuna de Maipú / Urinary lithiasis and its relation to the consumption of hard water in the Maipu Borough

INTRODUCCIÓN: La litiasis urinaria es una patología frecuente, que afecta principalmente a adultos en edad productiva, y que en el último tiempo ha presentado un aumento en la incidencia global. Cerca del 80 % de los cálculos se componen mayoritariamente de calcio. Existe controversia en la literatura sobre el rol que podría tener el consumo de aguas con altos índices de dureza y el riesgo de padecer litiasis. El objetivo de este estudio es identificar una posible asociación entre dureza de agua para consumos e incidencia de litiasis urinaria en la poblacion de Maipú. MATERIALES Y METODOS: Se incluyen en el estudio todos los pacientes atendidos por urólogos en forma ambulatoria electiva en el Hospital El Carmen de Maipú, por diagnóstico de litiasis urinaria, en los años 2015 y 2016, que residen en la comuna. Se georreferenciaron de acuerdo a sus direcciones en los distintos sectores de distribución de agua potable.Se realizó análisis fisicoquímico de muestras de agua extraídas de cada sector para determinar su dureza. Se estudiaron a través del índice de correlación de Pearson las posibles asociaciones entre dureza del agua e incidencia de litiasis. RESULTADOS: La dureza promedio del agua de Maipú es de 484 mg/L de CaCO3, valor que se encuentra por sobre el promedio regional y nacional. La incidencia anual de litiasis en la poblacion estudiada fue de 4,4 casos/10.000 habitantes, valor similar al promedio nacional. El índice de correlación de Pearson entre dureza de agua e incidencia anual fue de -0,51. CONCLUSIONES: No fue posible establecer una relación causal entre dureza de agua e incidencia de litiasis en la población estudiada. Se sugiere avanzar en esta misma línea con estudios futuros de casos y controles.AU

INTRODUCTION: Urinary lithiasis is a frequent pathology, which mainly affects adults in a productive age, and which-in recent times- has increased in terms of global incidence. About 80 % of the stones are composed mainly of calcium.There is controversy in literature addressing the possible relation amongst water consumption with high hardnessindexes and the risk of lithiasis. The objective of this study is to identify a possible association between water hardnessfor consumption and urinary lithiasis incidence in the Maipu population. MATERIALS AND METHODS: All patients assisted by urologists on an elective ambulatory basis, at the El Carmen Hospital in Maipú, diagnosed with urinary lithiasis, in the years 2015 and 2016, and who reside in the Borough have been included in the study. They were georeferenced according to their address in the different drinking water distribution areas. Physiochemical analysis of water samples extracted from each sector was carried out to determine its hardness. The possible associations between hardness of water and incidence of lithiasis were studied through the Pearson correlation index. RESULTS: The average water hardness in Maipu is 484 mg / L of CaCO3, a value that is above the regional and national average. The annual incidence of lithiasis in the studied population was 4.4 cases / 10,000 inhabitants, a value that is similar to the national average. The Pearson correlation index between water hardness and annual incidence was -0.51. CONCLUSIONS: It was not possible to establish a causal relation between water hardness and incidence of lithiasis in the studied population. It is suggested to advance in this same line with future case and control studies.

Peritonitis bacteriana espontánea por Listeria monocytogenes en un paciente con cirrosis hepática: reporte de un caso / Spontaneous bacterial peritonitis due to Listeria monocytogenes in a patient with cirrhosis: case report

Spontaneous bacterial peritonitis (SBP) is a frequent and severe complication in cirrhotic patients. Listeria monocytogenes is a rare cause of SBP, which should be suspected in individuals with impaired immunity such as advanced liver disease and inadequate response to standard antibiotic therapy. We report a case of a 72 year-old patient with liver cirrhosis secondary to alcohol consumption, asymptomatic carrier of Hepatitis B virus, diabetes Type II and coronary artery disease; who is admitted with a diagnosis of hepatic encephalopathy and suspicion of spontaneous bacterial peritonitis receiving empiric antibiotic treatment with ceftriaxona. Initially he showed clinical response but a few days later he got worse. Ascitic culture confirmed infection by Listeria monocytogenes. Antibiotic treatment was adjusted but patient continued deteriorating progressively, and finally died due to renal dysfunction.

La peritonitis bacteriana espontánea (PBE) es una complicación frecuente y grave en los pacientes cirróticos. Listeria monocytogenes es una causa poco frecuente de PBE, que debe sospecharse en individuos con inmunidad alterada como es la enfermedad hepática avanzada y con respuesta inadecuada a terapia antibiótica habitual. Presentamos el caso de un paciente de 72 años con antecedentes de cirrosis hepática secundaria a consumo de alcohol, portador asintomático del virus de la Hepatitis B (VHB), diabético tipo II y cardiópata coronario. Se hospitaliza por encefalopatía hepática secundaria a PBE, recibe tratamiento antibiótico empírico con ceftriaxona con respuesta clínica inicial y deterioro posterior. Cultivo de líquido ascítico confirma infección por Listeria monocytogenes. Pese a ajuste de tratamiento antibiótico, continúa empeorando y finalmente fallece por disfunción renal.

Actualización en el manejo de la hemorragia digestiva alta variceal / Update on the management of variceal upper gastrointestinal bleeding

Variceal bleeding is a severe complication of portal hypertension, associated to hepatic cirrhosis. It is more frequent in esophageal varices than in gastric varices. The first-line treatment is resuscitation, careful intravenous saline fluids infusions, prophylactic antibiotics and early combined use of vasoactive drugs and endoscopic therapy. Despite these measures, haemostasis failure is of 20 percent after 6 weeks. In these patients, the second-line treatment is transjugular intrahepatic portosystemic shunt (TIPS), procedure that requires an interventional radiologist. Therapeutic options are evaluated for bleeding esophageal varices, such as TIPS with covered stent as first-line treatment, portosystemic shunt surgery in Child-Pugh A patients as alternative to TIPS, the use of recombinant FVII in massive bleeding established by endoscopy and selfexpandable metallic stent in Child-Pugh B-C patients, instead of balloon. For gastric varices the use of balloon retrograde transvenous occlusion (BRTO) is described.

El sangrado variceal es una complicación grave de la hipertensión portal asociada a cirrosis hepática. Es más frecuente en várices esofágicas que gástricas. Como primera línea de tratamiento está la resucitación, volemización cuidadosa, profilaxis antibiótica y el uso combinado precoz de drogas vasoactivas junto a terapia endoscópica. A pesar de estas medidas, la hemostasia fracasa hasta en 20 por ciento a 6 semanas. En estos pacientes, la segunda línea de tratamiento es el Cortocircuito intrahepático portosistémico transyugular (Transjugular Intrahepatic Portosystemic Shunt- TIPS), procedimiento que requiere la participación de un radiólogo intervencionista. Se evalúan opciones terapéuticas para várices esofágicas sangrantes como el TIPS con stent recubierto usado de primera línea, la cirugía de shunt portosistémico en pacientes Child A como alternativa al TIPS, el uso de FVII recombinante en sangrado variceal masivo detectado mediante endoscopia, y el stent metálico autoexpandible en Child B-C en vez de balón. Para várices gástricas se describe el uso del balón oclusivo retrógrado transvenoso (B-RTO).

Biopsia hepática percutánea en pacientes ambulatorios: experiencia clínica de 23 casos / Percutaneous liver biopsy in ambulatory patients: clinic experience of 23 cases

La biopsia hepática sigue siendo importante en el diagnóstico de enfermedades del hígado, apareciendo las complicaciones del procedimiento dentro de las primeras horas, siendo necesario 4-6 horas de observación para su realización. Objetivos: Presentar nuestra casuística y protocolo de 23 casos de biopsia hepática percutánea en régimen ambulatorio. Materiales y Métodos: Revisión de fichas clínicas de pacientes a los que se les realizó el procedimiento. Se analizaron variables demográficas, exámenes de laboratorio, razón de indicación de biopsia y complicaciones mayores y menores durante fase hospitalaria y ambulatoria. Resultados: La edad promedio fue de 53,2 años. 69,56 por ciento eran mujeres y 30,4 por ciento hombres. El menor recuento plaquetario fue de 105.000 x mm3. No se observaron complicaciones mayores, y las menores ocurrieron en 91 por ciento en el período de observación y el 61 por ciento de ellas en las primeras dos horas. Conclusiones: Para la realización de biopsia hepática en pacientes ambulatorios, un período de observación hospitalaria de 5 horas parece ser suficiente, dado que en éste se pesquisan la mayoría de las complicaciones de una población bien seleccionada, permitiendo plantear la realización de este procedimiento en forma ambulatoria en nuestro país.

Hepatic biopsy is important in the diagnosis of hepatic diseases. The potential complications may appear in the first hours after the procedure, therefore it is necessary to consider a period of 4-6 hours of observation. Objectives: To present our protocol and 23 cases of percutaneous liver biopsies in ambulatory regime. Materials and Methods: Review of case histories (case report forms) of the patients that were subjected to the procedure. Demographic variables, laboratory tests, reasons for biopsy, and major and minor complications during hospitalization and ambulatory phase. Results: Average age was 53.2 years; of these, 69.56 percent were women and 30.4 percent men. The lowest plaquetary count was 105.000 x mm3. No major complications were observed, and some of them occurred in a 91 percent during the observation period, and 61 percent during the first two hours. Conclusions: A period of clinical observation of 5 hours seems enough for a biopsy in ambulatory patients. It is during this period when the majority of complications are observed in a well-selected population. This supports the idea of performing this procedure in an ambulatory or outpatient basis on our country.

Melanoma anorrectal primario: una causa infrecuente de rectorragia en el adulto mayor / Primary anorectal melanoma: an uncommon source of rectal bleeding in the elderly

El melanoma anorrectal primario es un tumor maligno muy infrecuente y con un pobre pronóstico. Se presenta un paciente de 66 años con rectorragia, en el cual el diagnóstico de melanoma anorrectal se efectuó por colonoscopia e histología. Se trató mediante una resección abdominoperineal. Se efectúa revisión de la literatura.

Primary anorectal melanoma is a very rare malignant tumor, with poor prognosis. A 66 years old man presenting with rectal bleeding is reported. The diagnosis of anorectal melanoma was confirmed by colonoscopy and histological findings. An abdominoperineal resection was performed. A review of the literature is presented.

Assessment of person-to-person transmission of hantavirus pulmonary syndrome in a Chilean hospital setting.

Person-to-person transmission of Andes hantavirus among healthcare workers was reported in Argentina for the first time in 1996. To determine whether such transmission of the virus occurred during a 1997 outbreak of hantavirus pulmonary syndrome (HPS) in southern Chile due to Andes virus, we conducted a serological and epidemiological study in the Coyhaique Regional Hospital, where the majority of HPS patients were admitted. Workers in every department of the hospital were evaluated for immunoglobulin G (IgG) and IgM hantavirus antibodies using the enzyme-linked immunosorbent assay (ELISA). A standardized questionnaire was used to determine the type and extent of exposure to HPS patients, as well as other potential risk factors and previous febrile respiratory illnesses requiring hospitalization. Less than half (44%) reported always using gloves when touching patients or their secretions; respiratory protection was not used. Of the 319 participants (87.9% of those eligible), 12 (3.7%) had IgG antibodies. This finding is consistent with the antibody prevalence in the community in which the participants lived. Of the 12 positive healthcare workers, six reported contact with HPS patients. A similar exposure was found in those who tested negative [6/140 (4%) compared to 6/179 (3%), P = 0.66]. There was no significant difference in the types of hospital activities performed or the number of hospitalizations for febrile respiratory illnesses between antibody-positive and antibody-negative individuals. These data suggest that there was no person-to-person transmission among healthcare workers during a recent outbreak of HPS in Southern Chile in 1997, despite the inconsistent use of any precautions against transmission.