Resultados del primer registro nacional de fibrosis pulmonar idiopática en Chile / Results of the first national register of idiopathic pulmonary fibrosis in Chile

INTRODUCCIÓN: La FPI es la neumonía intersticial idiopática más común, con cifras de incidencia y prevalencia que varían en el mundo por la poco uniforme manera de recolectar casos en los diferentes estudios. No hay cifras publicadas sobre la epidemiología de la FPI en Chile ni Latinoamérica. Se hace relevante conocerlas por la carga sanitaria que representan los pacientes con FPI y por la aprobación reciente de drogas antifibróticas de alto costo. El objetivo de este estudio fue realizar un registro de pacientes con FPI atendidos por neumólogos chilenos de diversos regiones del país, con los medios diagnósticos que habitualmente utilizan en la vida real. PACIENTES Y MÉTODOS: Se utilizó una encuesta electrónica en línea diseñada por el grupo de enfermedades pulmonares difusas del Instituto Nacional del Tórax para registro de pacientes con diagnóstico de FPI según criterios ATS/ERS/JRS/ALAT desde junio de 2015 a junio de 2017. RESULTADOS: 40 de los 200 neumólogos invitados enviaron casos de FPI de las 13 regiones del país, completando un total de 700 pacientes. 2/3 eran casos antiguos, un número similar de hombres y mujeres, 73% tienen patrón definitivo de UIP (Usual Interstitial Pneumonia) en tomografía axial computarizada, la mayoría eran pacientes sobre 60 años y en solo 16% se solicitó biopsia para diagnóstico. CONCLUSIONES: Un registro de 700 casos representa un número muy importante de pacientes con FPI en Chile que nos permite acercarnos a la caracterización de la cohorte y a fortalecer una red de especialistas dedicados al cuidado de estos pacientes y sus familias.

INTRODUCTION: Idiopathic pulmonary fibrosis is the most common idiopathic interstitial pneumonia, with incidence and prevalence figures varying worldwide because of the inconsistent way of collecting cases in different studies. There are no published figures on the epidemiology of IPF in Chile or Latin America. It is relevant to know them because of the health burden of patients with IPF and the recent approval for treatment purposes of high cost antifibrotic drugs. The objective of this study was to develop a clinical registry of patients with IPF treated by Chilean pulmonologists from different regions of the country, using the diagnostic means they usually use in real life. PATIENTS AND METHODS: An online electronic survey was designed by the group of diffuse pulmonary diseases of the "Instituto Nacional del Tórax" to register patients with diagnosis of IPF from June 2015 to June 2017 according to ATS/ERS/JRS/ALAT criteria. RESULTS: 40 of the 200 invited pulmonologists sent IPF cases from the country's 13 regions, completing a total of 700 patients. 2/3 were old cases, a similar number of men and women, 73% had definitive UIP pattern in CT, the majority were patients over 60 years old and in only 16% biopsy was requested for diagnosis. CONCLUSIONS: A register of 700 cases represents a very important number of patients with IPF in Chile that allows us to approach the characterization of the cohort and to strengthen a network of specialists dedicated to the care of these patients and their families.

OMENTAL INFARCTION: SURGICAL or CONSERVATIVE TREATMENT? A CASE REPORTS and CASE SERIES SYSTEMATIC REVIEW.

BACKGROUND: Omental infarction (OI) is an infrequent cause of acute abdominal pain and there is no consensus on whether conservative or surgical treatment is the best strategy when performing positive CT diagnosis. OBJECTIVES: To assess which of the two treatments is the most commonly adopted and compare outcomes in terms of success rate in resolution of symptoms and hospital length of stay. ELIGIBILITY CRITERIA: Case report and case series of patients with abdominal pain and positive diagnosis by CT of omental infarction. DATA SOURCES: PubMed, Science Direct and Google Scholar in combination with cross-referencing searches and manual searches of eligible articles from January 2000 to June 2018. PARTICIPANTS: Patients older than 18 years of age. METHODS: Patient characteristics and results were summarized descriptively. Categorical variables were assessed by chisquare test or Fischer's exact test, and continuous variables by the Wilcoxon-Mann-Whitney or Kruskal-Wallis test. Risk factors for failure of the conservative management were identified using multivariate logistic regression. RESULTS: 90 articles were included in the final analysis (146 patients). 107 patients (73.3%) received conservative treatment with a failure rate of 15.9% (patients needing surgery) and 39 patients (26.7%) received surgery as first treatment. The mean hospital length of stay was 5.1 days for the conservative treatment group and 2.5 days for the surgery group with statistically significant differences (p = 0.00). Younger age and white blood cells count ≥12000/µl were predictive factors of conservative treatment failure. CONCLUSIONS: Although conservative treatment is effective in most patients, surgery has advantages in terms of hospital length of stay.

Programa de prevención de las bacteriemias asociadas a catéteres venosos centrales / Program for prevention of central venous catheter-related bacteremia

Introducción: Las infecciones son las complicaciones más importantes asociadas al uso de los Catéteres Venosos Centrales (CVC), representan un riesgo 20 veces mayor de bacteriemias que los catéteres venosos periféricos. El objetivo de este estudio fue evaluar el efecto de la implementación de un paquete de medidas o "bundle" en las infecciones asociadas a catéteres venosos centrales (BACT- CVC) en la Unidad de Cuidados Intensivos del Hospital Garrahan (UCI). Métodos: El Programa de Intervención para disminuir las bacteriemias asociadas a catéteres venosos centrales requirió de la aplicación de cuatro paquetes de medidas y un subprograma para aumentar la adherencia a la higiene de manos. Se aplicó en todas las UCI, pero en el presente estudio se presenta como modelo de referencia el que se llevó a cabo en una de ellas. Período del estudio: se compararon 2 períodos: basal (1º Agosto de 2008 - 31 de Diciembre de 2009) y intervención (1º de Enero 2010 al 31 de Diciembre de 2011). La tasa de BACT - CVC se calculó en concordancia con los protocolos utilizados por el sistema NHSN - CDC de los Estados Unidos y el sistema nacional VIHDA. La base de datos utilizada para el estudio fue el software provisto por el programa VIHDA. Se compararon las tasas de BACT - CVC en el período previo y posterior a las intervenciones realizadas. Para el análisis estadístico se utilizó el programa EPIINFO. Se consideró estadísticamente significativo un valor de p < 0.05. Resultados: en el primer período (Agosto 2008 - Diciembre 2009) se produjeron un total de 44 BACT - CVC, con una tasa promedio de 9.64 BACT-CVC por 1000 días-catéter versus 17 BACT - CVC, tasa promedio de 4.41 BACT-CVC por 1000 días-catéter en el período en que se desarrolla el programa de intervención. Esta disminución resulta estadísticamente significativa (Chi cuadrado; valor P= 0,0048; RR 0,46; IC 95%: 0,26 - 0,80). Conclusiones: La aplicación de los combos y el subprograma para mejorar la adherencia a la higiene de manos según orientación de la OMS y aplicando Estrategias Multimodales, resultaron en una mejora significativa en la tasa de BACT- CVC (AU)

Introduction: Infections are the main complication associated with the use of central venous catheters (CVC), accounting for an infection risk about 20 times that of peripheral venous catheters. The aim of this study was to assess the effect of the implementation of sets of measures or "bundle" for the prevention of CVC-associated bacteremia (CVC-BACT) in the ICU. Methods: The intervention program for the reduction of CVC-BACT consisted of four sets of measures and a sub-program to increase adherence to hand hygiene. Bundle use was started in all PICUs, however, in this study implementation of the program in one of them was used as a reference model. Study period: Two periods were compared: Baseline (August 1, 2008 ­ December 31, 2009) and intervention (January 1, 2010 ­ December 31, 2011). The CVC-BACT rate was calculated according to the NHSN-CDC protocols of the United States and the Argentine VIHDA system. For the data base of the study software provided by the VIHDA program was used. CVC-BACT rates before and after the intervention period were calculated. For statistical analysis the EPIINFO program was used. A p < 0.05 was considered significant. Results: In the first period (August 2008 - December 2009) 44 CVC-BACT occurred, with a mean CVC-BACT rate of 9.64 per 1000 catheter days versus 17 CVC-BACT, mean CVC-BACT rate of 4.41 per 1000 catheter days, in the intervention period. This decrease was statistically significant (Chi square 7.94; p = 0.0048; RR 0.46; 95% CI: 0.26 ­ 0.80). Conclusions: Bundle use and the subprogram for better adherence to hand hygiene, according to WHO guidelines and applying multimodal strategies, resulted in a significantly lower CVC-BACT rate (AU)

Development of liver fibrosis during aging: effects of caloric restriction.

Liver is the central metabolic organ of the body and diet is considered one of the main environmental factors that can impact on aging liver. In the elderly stage liver function is relatively well conserved although there are a variety of not well defined morphological changes related to liver fibrosis which is commonly associated with an inflammatory state. The aim of this paper is to study these alterations during the physiological process of aging in Wistar rats and also test if caloric restriction (CR) could ameliorate them. As fibrosis is associated to hepatic stellate cell (HSC) function we also analyzed these cells during aging. Livers from five groups of male Wistar rats (3-, 8-, 24-months old ad libitum and 8- and 24-months caloric restricted rats) were used in this study. Histological analysis, expression of genes implicated in liver fibrosis and the status of inflammatory step-pathways as p38 mitogen-activated protein kinase (p38-MAPK), c-Jun N-terminal kinase (JNK) and the nuclear factor kappa B (NFkB) isoforms, p50 and p65, in cytosolic and nuclear fractions were performed. During elderly, associated with morphological change of HSC, there is a progressive increase in collagen deposition due to an inhibition in collagen degradation. Higher expression of cytokines and the activation of inflammatory pathways are associated with aging. CR ameliorates these circumstances being more effective when it started in middle age. In conclusion elderly stage is associated to a mild fibrotic and inflammatory state in the liver which could be ameliorated after CR.

Bloqueo poplíteo para reducciones ortopédicas de extremidad inferior / Popliteal block for inferior extremity orthopedic reductions

Popliteal sciatic block is considered a good alternative analgesia for performing leg, ankle or foot’s fracture reduction at an emergency room. We hypothesized that performing the procedure in prone position rather than supine is better tolerated by the patients. Since 1995, we have used popliteal sciatic block carried out in both positions. Our study consists in 507 patients with fractures of the involved segment of the lower limb who presented at the emergency room from 1998 to 2008. All of them were treated with closed reduction and immobilization under popliteal sciatic block analgesia. The Procedure was performed by orthopedic surgeons guided by an anesthesiologist. 22.5 ml of lidocaine at 1.33 percent was used for obtaining paresthesia. Pain outcome was evaluated using the Visual Analog Scale (VAS) and by patient and surgeon questionnaire. Patient and surgeon’s satisfaction was 90 percent and 94 percent, respectively. Our series reports a simple, reliable and safe analgesia technique for closed fracture’s reduction of the lower limb at the emergency department.

Para reducciones de fracturas de pierna, tobillo y pie generalmente basta un bloqueo ciático, que realizado en la posición prona, produce dolor e incomodidad al paciente. Desde el año 1995 utilizamos en nuestro hospital el bloqueo poplíteo vía posterior en posición supina para estos procedimientos. Se analiza la experiencia de 10 años con 507 pacientes con lesiones del segmento a los cuales se les practicó reducción de su fractura con bloqueo poplíteo realizado por residentes de Ortopedia y Traumatología capacitados y supervisados por anestesiólogos. Se utilizó lidocaína 22,5 ml al 1,33 por ciento obteniéndose parestesias. La evaluación se realizó mediante escala EVA y encuesta al operador y paciente. El 90 por ciento de los pacientes y el 94 por ciento de los operadores dan una evaluación positiva del procedimiento. La técnica siendo simple, confiable y segura proporciona una excelente anestesia para reducciones de la extremidad inferior.

Bloqueo iliofascial continuo en artroplastia total de rodilla: comparación con la analgesia epidural continua / Continuous iliofascial block in total knee arthroplasty: comparison with continuous epidural analgesia

Introducción: La artroplastia total de rodilla (ART) induce dolor posoperatorio moderado a severo. El objetivo de este ensayo clínico fue comparar la analgesia posoperatoria del bloqueo femoral iliofascial continuo (BIFC) con la analgesia epidural continua (AEPIC) en pacientes sometidos a ATR. Pacientes y métodos: Ensayo clínico, prospectivo, aleatorizado, en pacientes ASA I a III estables, divididos en dos grupos. Grupo 1: anestesia espinal (AE) + BIFC con infusión de bupivacaína (B) 0,1 por ciento en infusión continua (IC) a 10 ml/h. Grupo 2: anestesia combinada espinal-epidural + AEPIC con B a 0,1 por ciento en IC a 8 ml/h. Se registraron: el dolor posoperatorio según la escala visual análoga, tanto en reposo (EVA estático) como en movimiento (EVA dinámico), cada 3 h y durante 24 h; el consumo de morfina endovenosa (EV) y la incidencia de efectos adversos (EA). Se consideró un valor p < 0,05 como estadísticamente significativo. Resultados: Fueron incluidos 30 pacientes, 15 en cada grupo. No hubo diferencias entre los grupos con respecto a edad, peso, índice de masa corporal, sexo, estado ASA, duración de la cirugía, consumo de morfina EV e incidencia de EA. Los EVA posoperatorio, tanto estático como dinámico, fueron similares en ambos grupos de estudio. Hubo una significativa mayor proporción de hipotensión arterial en el grupo AEPIC. Conclusión: El BIFC y la AEPIC proporcionan una analgesia eficiente y de similar calidad a pacientes sometidos a ATR. El BIFC presenta menor incidencia de complicaciones hemodinámicas en el período posoperatorio. Ambas técnicas permiten una rehabilitación precoz y segura.

Introduction: Total knee arthroplasty (TKA) induces mild to severe postoperative pain. The purpose of this clinical study was to compare the postoperative analgesic efficacy of an iliofascial femoral block (IFFB) versus continuous epidural analgesia (CEA) for the control of postoperative pain after total knee arthroplasty (TKA). Patients and Methods: A prospective, randomized study of 30 stable patients, ASA Class I- III. They were divided into two groups of 15 patients. Group 1 (n = 15) IFFB: continuous infusion (CI) of bupivacaine (B) 0.1 percent at 10 ml/h; Group 2 (n = 15) CEA: CI of B 0.1 percent at 8 ml/h. In the postoperative period the pain was measured every 3 hours using the visual analogue scale (VAS) for 24 h, assessing pain during movement (dynamic pain) and absolute stillness (static pain). The consumption of IV morphine and the incidence of undesirable effects were noted. A value of p < 0.05 was considered statistically significant. Results: The 2 groups were comparable in age, weight, corporal mass index, sex, and ASA class. No difference was noted between the 2 groups in the VAS score both dynamic and static. The consumption of morphine was similar in the 2 groups. The IFFB group had less significant incidence of arterial hypotension in the first 24 h. Conclusions: The IFFB provides a good postoperative analgesia comparable with the CEA. The IFFB provided less incidence of arterial hypotension.

Introdução: A artroplastia total de joelho (ART) induz dor pósoperatória moderada a severa. O objetivo deste ensaio clínico foi comparar a analgesia pós-operatória do bloqueio femoral iliofascial contínuo (BIFC) com a analgesia epidural contínua (AEPIC) em pacientes submetidos a ATR. Pacientes e métodos: Ensaio clínico, prospectivo, randomizado, em pacientes ASA I a III estáveis, divididos em dois grupos. Grupo 1: Anestesia espinhal (AE) + BIFC com infusão de bupivacaína (B) 0,1 por cento em infusão contínua (IC) a 10 ml/h. Grupo 2: Anestesia combinada espinhalepidural + AEPIC com B a 0,1 por cento em IC a 8 ml/h. Foram registrados: a dor pós-operatória medida pela escala visual análoga, tanto em repouso (EVA estático) como em movimento (EVA dinâmico), a cada 3 h e durante 24 h; o consumo de morfina endovenosa (EV) e a incidência de efeitos adversos (EA). Considerou-se um valor p < 0,05 como estatisticamente significativo. Resultados: Foram incluídos 30 pacientes, 15 em cada grupo. Não houve diferenças entre os grupos no que diz respeito a idade, peso, índice de massa corporal, sexo, estado ASA, duração da cirurgia, consumo de morfina EV e incidência de EA. Os EVA pós-operatório, tanto estático como dinâmico, foram similares em ambos grupos de estudo. Os casos de hipotensão arterial foram significativamente mais importante no grupo AEPIC. Conclusão: O BIFC e a AEPIC proporcionam uma analgesia eficaz e de qualidade similar a pacientes submetidos a ATR. A incidência de complicações hemodinâmicas no período pós-operatório é menor no BIFC. Ambas técnicas permitem uma reabilitação precoce e segura.

Tissue-specific PAI-1 gene expression and glycosylation pattern in insulin-resistant old rats.

Increased levels of plasminogen activator inhibitor-1 (PAI-1) have been associated with obesity, aging, insulin resistance, and type 2 diabetes, conditions that contribute to increased cardiovascular risk. PAI-1 is expressed in a variety of tissues, but the cellular origin of plasma PAI-1 is unknown. To link insulin resistance, aging, and cardiovascular disease, we examined the expression and glycosylation pattern of PAI-1 in liver and white adipose tissue (WAT) from adult (3 mo) and insulin-resistant old (24 mo) Wistar rats. Glycosylated PAI-1 protein was also purified by affinity chromatography from endothelial culture supernatans to analyze its inhibitory activity. We also analyzed the contribution of adipocytes and stromal vascular cells from WAT to PAI-1 levels with aging. Aging caused a significant increase of PAI-1 mRNA (P < 0.001) in WAT that was predominantly due to the adipocytes and not to stroma-vascular cells, while there was no modification in liver from aged rats. Moreover, PAI-1 expression increased during preadipocyte differentiation (P < 0.001). Furthermore, we found a tissue-dependent PAI-1 glycosylation pattern: adipose tissue only expresses the glycosylated PAI-1 form, whereas the liver mainly expresses the nonglycosylated form. Finally, we also found evidences suggesting that the glycosylated PAI-1 form shows higher inhibitory activity than the nonglycosylated. Our data suggest that WAT may be a major source of the elevated plasma levels of PAI-1 in insulin-resistant old rats. Additionally, the high degree of PAI-1 glycosylation and activity, together with the significant increase in visceral fat in old rats, may well contribute to an increased cardiovascular risk associated with insulin-resistant states.

La inervación sensitiva segmentaria dermatomas, miotomas y esclerotomas / The segmentary sensitive innervation: dermatomes, myotomes and sclerotomes

Los mapas de dermatomas, miotomas y esclerotomas son usados por los neurólogos y por los anestesiólogos regionalistas en su práctica clínica habitual. La determinación de la sensibilidad de las diferentes estructuras del cuerpo humano se inició en el siglo 19, continúa hasta nuestros días y en general los nuevos métodos empleados para la determinación de la sensibilidad han corroborado las investigaciones de los primitivos autores. Al analizar la historia de la confección de mapas de sensibilidad de piel, músculo y hueso encontramos a todas las grandes figuras de la Neurología involucradas de una u otra forma en la investigación de este tema fascinante y observamos como el ingenio, la investigación sistemática y también el análisis de enfermedades y malformaciones, que permiten objetivar dermatomas y esclerotomas de otra manera invisibles, han permitido avanzar cada vez más en la confección de estos mapas. Debe tenerse presente que todos los mapas de dermatomas están compuestos de muchas observaciones individuales, ya que en cada persona se determinan sólo unos pocos dermatomas. Por esta razón todos los mapas que muestran dermatomas para todo el cuerpo deben ser vistos como aproximaciones que no toman en cuenta las variaciones individuales. Además a pesar de que generalmente se asume el dermatoma como una definición anatómica los mapas en uso han sido determinados por métodos fisiológicos. Todo lo anterior unido al hecho que se han usado métodos diferentes por cada investigador puede explicar las variaciones que se observan entre diferentes autores.

Correlation between dental maturation and bone growth markers in paediatric patients.

AIM: Many studies have been made to evaluate the growth, development and maturation of cervical vertebrae. These studies make clear how those vertebrae have growth patterns and centre of ossification similar to those in carpal bones, therefore cervical vertebrae can be used to determine bone age. The aim of the present study is the observation of cervical vertebrae in cephalometric radiographs to determine the bone age in a paediatric population and relate it to dental maturation. MATERIALS AND METHODS: The sample was composed of 203 children from Madrid, aged between 2 and 10 years. There were 86 males and 117 females, in each case a panoramic was taken to determine dental calcification using Demirjian method and a cephalometric radiograph was taken to evaluate cervical vertebrae maturation. Different vertical and horizontal dimensions were measured to determine maturation. RESULTS: The results show that there is a positive relationship between age and size of cervical vertebrae. The average horizontal measurements of the third, fourth and fifth cervical vertebrae presented statistically significant differences in size (p<0.05), being larger in boys than in girls. Statistical correlation was found between dental maturation and increased left vertical measures from third (C3VI) and fourth cervical vertebrae (C4VI), as well as middle vertical measure from fourth cervical vertebra (C4VMD). CONCLUSION: Significant changes in size were observed only in vertical measurements and the predictive measurements for dental maturation were C4VI, C4VMD and C3VI.

Differential gene expression of insulin receptor isoforms A and B and insulin receptor substrates 1, 2 and 3 in rat tissues: modulation by aging and differentiation in rat adipose tissue.

The insulin receptor (IR) occurs as two alternatively spliced isoforms, IR-A (exon 11-) and IR-B (exon 11+), which exhibit functional differences and are expressed in a tissue-specific manner. The IR substrate (IRS) proteins 1, 2 and 3 also differ in function and tissue distribution. Here we show the differential gene expression of IRs and IRSs in several rat target tissues of insulin action. IR-B is significantly higher than IR-A in epididymal white adipose tissue and adipogenesis induces a shift in the alternatively spliced species of IR from the A to the B isoform. Moreover, since aging in the rat is associated with the development of insulin resistance we looked for alterations of expression of these proteins in adipocytes from old rats. Our results reveal that there is a specific decrease in the expression of the IR-B isoform, as well as both mRNA and protein levels of IR, IRS-1 and IRS-3 being significantly decreased, in epididymal adipose tissue from old compared with adult rats. It is concluded that the down-regulation of early components of the insulin transduction pathway in a primary insulin target tissue could be related to the insulin resistance of aging.

Ageing increases SOCS-3 expression in rat hypothalamus: effects of food restriction.

Aged Wistar rats are characterized by leptin and insulin resistance. The expression of SOCS-3 in hypothalamus increases with ageing. Food restriction during 3 months decreases obesity Lee index in aged rats with respect to their ad libitum aged-mates and brings serum leptin concentrations to values close to those of young rats. Food restriction partially reverts the increases in SOCS-3 mRNA levels associated with ageing. These results suggest that SOCS-3 may be a mediator of hypothalamic leptin resistance in the aged Wistar rat and that the hyperleptinemia associated with ageing is, at least in part, responsible for the increase of SOCS-3 expression in hypothalamus.

Decreased leptin uptake in hypothalamic nuclei with ageing in Wistar rats.

Leptin interacts with specific receptors in hypothalamic nuclei and modulates energy balance. Growing evidence has shown the association of obesity and hyperleptinaemia with non-insulin-dependent diabetes mellitus and insulin resistance. The aged Wistar rat shows peripheral insulin resistance in the absence of obesity and alterations of glucose homeostasis. However, it is not known whether, in these animals, the leptin action is altered. Here we studied the effect of ageing on plasma leptin concentration and the ability of hypothalamic nuclei to capture i.c.v.-injected digoxigenin-labelled leptin. Our data indicate that 24-month-old animals are hyperleptinaemic. However, daily food intake was greater in old animals, suggesting that they are leptin resistant. Leptin uptake in the hypothalamus was reduced in old rats. This uptake was a receptor-mediated process as demonstrated by displacement. Leptin accumulation in hypothalamic nuclei was partially colocalized with neuropeptide Y fibres. Immunohistochemical and western blot analyses showed a lower amount of the long form of leptin receptors in the hypothalamus of aged rats. Analysis by RT-PCR also demonstrated a decreased expression of leptin receptor mRNA in old animals. We conclude that the lower leptin uptake may be explained, at least in part, by a decreased amount of receptors in hypothalamic neurones of the aged rats.

Purification and characterization of a digestive cathepsin D proteinase isolated from Tribolium castaneum larvae (Herbst).

A digestive proteinase was isolated from larval extracts of Tribolium castaneum. The enzyme was partially purified using gel-filtration and ion-exchange chromatography. It is an acidic proteinase with a maximal activity at pH 3. Considering its inhibition by Pepstatin A, plus its selectivity to hydrolyze hemoglobin but not bovine serum albumin, it was classified as Cathepsin D proteinase. Its relative molecular weight is 22 kDa and it shows a high sensitivity to temperature. Unlike other cathepsin D found in animals, this enzyme is free of carbohydrate, and its activity is not affected by the presence of different anions which are known to affect the activity of plant aspartic proteinases.

Purification, characterization, and complete amino acid sequence of a trypsin inhibitor from amaranth (Amaranthus hypochondriacus) seeds.

A protein proteinase inhibitor was purified from a seed extract of amaranth (Amaranthus hypochondriacus) by precipitation with (NH4)2SO4, gel-filtration chromatography, ion-exchange chromatography, and reverse-phase high-performance liquid chromatography. It is a 69-amino acid protein with a high content of valine, arginine, and glutamic acid, but lacking in methionine. The inhibitor has a relative molecular weight of 7400 and an isoelectric point of 7.5. It is a serine proteinase inhibitor that recognizes chymotrypsin, trypsin, and trypsin-like proteinase activities extracted from larvae of the insect Prostephanus truncatus. This inhibitor belongs to the potato-I inhibitor family, showing the closest homology (59.5%) with the Lycopersicum peruvianum trypsin inhibitor, and (51%) with the proteinase inhibitor 5 extracted from the seeds of Cucurbita maxima. The position of the lysine-aspartic acid residues present in the active site of the amaranth inhibitor are found in almost the same relative position as in the inhibitor from C. maxima.

Contaminación por ruido en pabellón / Noise pollution in the operating room

La contaminación por ruido es una realidad en nuestro medio. El nivel de ruido intraoperatorio se aproxima a los 75 dBA como promedio. Estos niveles son superiores a los mínimos que producen alteraciones en diversos sistemas del organismo. En las clínicas privadas los ambientes son menos ruidosos que en los hospitales estatales, probablemente por menor presión asistencial y por una construcción más moderna. Es recomendable mantener el mínimo personal necesario ya que el nivel de ruido aumenta proporcionalmente al número de personas; evitar conversaciones innecesarias y alejar las fuentes de ruido de los pacientes y del personal

Sex chromosome polymorphism in Oryzomys longicaudatus philippii (Rodentia, Cricetidae).

Oryzomys longicaudatus philippii has a diploid number 2N = 56 (N.F. = 70). A polymorphism of X-chromosomes is described and a duplication as causal mechanism is postulated. The degree of chromosomal differences among the 4 karyological forms of O. longicaudatus and between those forms with O. l. philippii, enable us to postulate the level of full species for all of them.