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OBJECTIVE: To describe and analyze the relationship between pregnancy-related anxiety, prenatal distress, and individual resilience in pregnant women during the first trimester of pregnancy and compare it with the obstetric variable of parity. METHOD: Quantitative, descriptive, cross-sectional study using non-probabilistic circumstantial sampling. A total of 144 women participated. The Prenatal Distress Questionnaire, the Resilience Scale, and the Pregnancy-Related Anxiety Questionnaire were used. A descriptive analysis with measures of central tendency was performed, and the reliability of the instruments was assessed. RESULTS: The average age was 33.57 years. 58.3% were multiparous and 41.7% primiparous. Anxiety was found in 21.5% and very high levels of resilience in 54.9%. Primiparous women showed higher levels of worry about the future and fear of childbirth than multiparous women. Pregnant women with high resilience showed lower levels of anxiety and stress. CONCLUSION: Pregnant women with higher levels of resilience show less anxiety and stress during the first trimester of pregnancy. Primiparous women show more anxiety and stress than multiparous women.

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ABSTRACT Objective: To describe and analyze the relationship between pregnancy-related anxiety, prenatal distress, and individual resilience in pregnant women during the first trimester of pregnancy and compare it with the obstetric variable of parity. Method: Quantitative, descriptive, cross-sectional study using non-probabilistic circumstantial sampling. A total of 144 women participated. The Prenatal Distress Questionnaire, the Resilience Scale, and the Pregnancy-Related Anxiety Questionnaire were used. A descriptive analysis with measures of central tendency was performed, and the reliability of the instruments was assessed. Results: The average age was 33.57 years. 58.3% were multiparous and 41.7% primiparous. Anxiety was found in 21.5% and very high levels of resilience in 54.9%. Primiparous women showed higher levels of worry about the future and fear of childbirth than multiparous women. Pregnant women with high resilience showed lower levels of anxiety and stress. Conclusion: Pregnant women with higher levels of resilience show less anxiety and stress during the first trimester of pregnancy. Primiparous women show more anxiety and stress than multiparous women.

RESUMO Objetivo: Descrever e analisar a relação entre a ansiedade relacionada à gravidez, o estresse pré-natal e a resiliência individual em mulheres grávidas durante o primeiro trimestre da gravidez e compará-la com a variável obstétrica da paridade. Método: Estudo quantitativo, descritivo, transversal usando amostragem circunstancial não probabilística. Um total de 144 mulheres participaram. Foram utilizados o Questionário de Estresse Pré-natal, a Escala de Resiliência e o Questionário de Ansiedade Relacionada à Gravidez. Foi realizada uma análise descritiva com medidas de tendência central, e a confiabilidade dos instrumentos foi avaliada. Resultados: A idade média foi de 33,57 anos. 58,3% eram multiparas e 41,7% primíparas. Ansiedade foi encontrada em 21,5% e níveis muito altos de resiliência em 54,9%. Mulheres primíparas apresentaram níveis mais altos de preocupação com o futuro e medo do parto do que mulheres multiparas. Mulheres grávidas com alta resiliência mostraram níveis mais baixos de ansiedade e estresse. Conclusões: Mulheres grávidas com níveis mais altos de resiliência apresentam menos ansiedade e estresse durante o primeiro trimestre da gravidez. Mulheres primíparas mostram mais ansiedade e estresse do que mulheres multiparas.

RESUMEN Objetivo: Describir y analizar la relación entre la ansiedad relacionada con el embarazo, el distrés prenatal y la resiliencia individual, en mujeres gestantes durante el primer trimestre de embarazo y compararlo con la variable obstétrica de paridad. Método: Estudio cuantitativo, descriptivo y transversal utilizando muestreo no probabilístico circunstancial. Participaron 144 mujeres. Se emplearon el Cuestionario de Distrés Prenatal, la Escala de Resiliencia y el Cuestionario de Ansiedad Relacionada con el Embarazo. Se realizó un análisis descriptivo con medidas de tendencia central y se evaluó la confiabilidad de los instrumentos. Resultados: La edad promedio fue de 33,57 años. El 58,3% eran multíparas y el 41,7% primíparas. El 21,5% presenta ansiedad y el 54,9% niveles muy altos de resiliencia. Las primíparas mostraron mayores niveles preocupación sobre el futuro y miedo al parto que las multíparas. Las gestantes con alta resiliencia muestran valores más bajos en ansiedad y estrés. Conclusiones: Las gestantes con niveles más elevados de resiliencia manifiestan menos ansiedad y estrés durante el primer trimestre de embarazo. Las primíparas presentan más ansiedad y estrés que las multíparas.

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BACKGROUND: Experimental reports have demonstrated that florfenicol (FFC) exerts potent anti-inflammatory effects, improving survival in a murine endotoxemia model. Considering the anti-inflammatory and immunomodulatory properties of pentoxifylline (PTX) as an adjuvant to enhance the efficacy of antibiotics, the anti-inflammatory effects of the interaction FFC/PTX over the E. coli Lipopolysaccharide (LPS)-induced acute inflammatory response was evaluated in rabbits. METHODS: Twenty-five clinically healthy New Zealand rabbits (3.8 ± 0.2 kg body weight: bw), were distributed into five experimental groups. Group 1 (control): treated with 1 mL/4 kg bw of 0.9% saline solution (SS) intravenously (IV). Group 2 (LPS): treated with an IV dose of 5 µg/kg of LPS. Group 3 (pentoxifylline (PTX) + LPS): treated with an oral dose of 30 mg/kg PTX, followed by an IV dose of 5 µg/kg of LPS 45 min after PTX. Group 4 (Florfenicol (FFC) + LPS): treated with an IM dose of 20 mg/kg of FFC, followed by an IV dose of 5 µg/kg of LPS 45 min after FFC administration. Group 5 (PTX + FFC + LPS): treated with an oral dose of 30 mg/kg of PTX, followed by an IM dose of 20 mg/kg of FFC, and, 45 min after an IV dose of 5 µg/kg of LPS was administered. The anti-inflammatory response was evaluated through changes in plasma levels of interleukins (TNF-α, IL-1ß and IL-6), C-reactive protein (CRP), and body temperature. RESULTS: It has been shown that each drug produced a partial inhibition over the LPS-induced increase in TNF-α, IL-1ß, and CRP. When both drugs were co-administered, a synergistic inhibitory effect on the IL-1ß and CRP plasma concentrations was observed, associated with a synergic antipyretic effect. However, the co-administration of PTX/FFC failed to modify the LPS-induced increase in the TNF-α plasma concentrations. CONCLUSIONS: We concluded that the combination of FFC and PTX in our LPS sepsis models demonstrates immunomodulatory effects. An apparent synergistic effect was observed for the IL-1ß inhibition, which peaks at three hours and then decreases. At the same time, each drug alone was superior in reducing TNF-α levels, while the combination was inferior. However, the peak of TNF-α in this sepsis model was at 12 h. Therefore, in rabbits plasma IL-1ß and TNF-α could be regulated independently, thus, further research is needed to explore the effects of this combination over a more prolonged period.

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This work aimed to assess the effects of the coadministration of pentoxifylline (PTX) on the pharmacokinetic profile of florfenicol (FFC) after intramuscular administration in rabbits. Ten New Zealand white rabbits, 1 year of age and 3.9 ± 0.1 kg body weight, were assigned according to a randomized block design to Group 1 (FFC): treated with 30 mg/kg of FFC intramuscularly, and Group 2 (PTX + FFC) treated with an oral dose of 30 mg/kg PTX 45 min before the intramuscular injection of 30 mg/kg FFC. Blood samples were collected before and at different times between 0.5 and 12.0 h after drug administration. FFC plasma concentrations were determined by high-performance liquid chromatography. Results showed that IM injection of the long-acting formulation of FFC in rabbits resulted in a slow increase in mean plasma concentrations reaching a Cmax of 3.09 ± 0.52 ug/mL at 2.8 ± 0.45 h (Tmax ) after drug administration. While coadministration of PTX and FFC decreased the time to achieve the maximal concentration by modifying the absorption of FFC without changes in the other pharmacokinetic parameters.

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OBJECTIVES: We evaluated the VE and the mutations of the viruses present in the Mexican population at the beginning of 2018. METHODS: We diagnosed influenza in outpatients with a high-performance Rapid Influenza Diagnostic Test (RIDT) qRT-PCR. Descriptive statistics were used to describe the study population, while the chi-square test was used to determine clinical variables. VE was analyzed through a negative test design. We sequenced the hemagglutinin (HA) gene, performed a phylogenetic analysis, and analyzed the nonsynonymous substitutions both in and outside antigenic sites. RESULTS: Of the 240 patients analyzed, 42.5% received the trivalent vaccine, and 37.5% were positive for influenza. The VE for the general population for any influenza virus type or subtype was 37.0%, while the VE for the predominant influenza A(H3N2) subtype was the lowest (19.7%). The phylogenetic analysis of HA showed the co-circulation of clades and subclades 3C.2a1, 3C.2a1b, 3C.2a2, 3C.2a2re, 3C.2a3, and 3C.3a with identities approximately 97-98% similar to the vaccine composition. CONCLUSION: Low VE was related to the co-circulation of multiple clades and subclades of influenza A(H3N2), with sufficient genetic and phenotypic distance to allow for the infection of vaccinated individuals.

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RESUMEN Introducción: Los tiempos de atención médica son un factor relevante para la mortalidad por infarto agudo de miocardio con elevación del segmento ST (IAMCEST). Objetivos: Evaluar los tiempos de reperfusión en pacientes con IAMCEST participantes de un programa de atención médica cardiológica basada en telemedicina en la provincia de La Pampa durante el período transcurrido entre agosto de 2018 y diciembre de 2021. Material y Métodos: Este programa consiste en la protocolización de la atención de los pacientes que cursan un síndrome coronario agudo (SCA) en las diferentes localidades de la provincia, con asistencia cardiológica remota las 24 horas del día, que incluye tanto la asistencia diagnóstica como la coordinación de las medidas terapéuticas, incluyendo la posibilidad de administrar trombolíticos a nivel local, con asistencia remota. Resultados: De un total de 72 IAMCEST evaluados, 44 recibieron como terapia de reperfusión trombolisis, 25 angioplastia primaria, y 3 trombolisis seguida de angioplastia de rescate. De los 47 sujetos que recibieron trombolisis, sólo 5 requirieron de traslado al centro de referencia para realizar este procedimiento. La mediana de tiempo puerta-aguja fue de 24 minutos y el tiempo puerta-balón fue de 105 minutos. El 28% de los sujetos con angioplastia primaria tuvieron un tiempo puerta-balón inferior a los 90 minutos y el 53,2% de los tratados con trombolíticos cumplieron con un tiempo puerta-aguja menor a 30 minutos. Conclusiones: La implementación de un programa de atención descentralizada guiada por telemedicina se asoció a un elevado porcentaje de cumplimento de las metas de implementación de la terapia de reperfusión basada en fibrinolíticos.

ABSTRACT Background: Timing of medical care is a relevant factor for ST-segment elevation myocardial infarction (STEMI) mortality. Objectives: The aim of the present study is to evaluate reperfusion times in STEMI patients participating in a telemedicinebased cardiology care program in the province of La Pampa during the period between August 2018 and December 2021. Methods: This program consists of a protocol for the management of patients with acute coronary syndrome (ACS) in the different locations of the province, with 24-hour remote assistance provided by cardiologists including both diagnostic support and coordination of on-site thrombolysis. Results: Of a total of 72 STEMI patients evaluated, 44 received thrombolysis as reperfusion therapy, 25 received primary percutaneous coronary intervention, and 3 received thrombolysis followed by rescue percutaneous coronary intervention. Of the 47 subjects who received thrombolysis, only 5 required to be transferred to the referral center for this procedure. Median door-to-needle time was 24 minutes and door-to balloon-time was 105 minutes. Twenty-five percent of the subjects had a door-to-balloon time <90 minutes and 53.2% fulfilled a door-to-needle time <30 minutes. Conclusions: The implementation of a telemedicine-guided program for decentralized management of STEMI patients was associated with a high percentage of compliance with the goals of implementing fibrinolytic-based reperfusion therapy.

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Resumen Objetivo: Este estudio se llevó a cabo para valorar las consecuencias de la perforación iatrogénica de la vesícula biliar (PIVB), investigando su asociación con complicaciones posoperatorias, uso de antibióticos y drenajes, duración de la cirugía y estancia posoperatoria. Materiales y Método: Se incluyeron 1.703 pacientes con colecistectomía laparoscópica electiva, divididos en dos grupos: con PIVB (Grupo 1; n = 321) y sin PIVB (Grupo 2; n = 1.382). Se compararon los resultados entre ambos grupos. Resultados: El porcentaje de PIVB fue de 18,85%. El vertido aislado de bilis ocurrió en 241 pacientes (14,15%) y el de bilis y cálculos en 80 pacientes (4,64%). La incidencia de infección del sitio quirúrgico no fue diferente entre ambos grupos. La incidencia de PIVB fue mayor en varones (43,3% vs 31,3%), pacientes con adherencias perivesiculares (17,75% vs. 10,5%) y pacientes con diagnóstico histológico de colecistitis aguda (11,52% vs. 4,92%). La PIVB se asoció significativamente con mayor duración de la cirugía (77,3 vs. 65,4 minutos), mayor uso de drenajes y antibióticos y mayor estancia posoperatoria. No hubo complicaciones tardías. Discusión y Conclusión: La PIVB no aumenta la incidencia de infección, pero se asocia con un mayor uso de drenajes y antibióticos, mayor duración de la cirugía y mayor estancia posoperatoria.

Aim: This study was conducted to evaluate the outcomes in patients with iatrogenic gallbladder perforation (IGP), investigating its association with postoperative complications, use of antibiotics and drains, operative time and postoperative stay. Materials and Method: 1703 patients who underwent elective laparoscopic cholecystectomy were included and divided in two groups: with IGP (Group 1, n = 321) and without IGP (Group 2, n = 1382). We compared the outcomes between both groups. Results: The IGP rate was 18.85%. Isolated bile spillage occurred in 241 patients (14.15%), and stone spillage in 80 patients (4.64%). The incidence of surgical site infections was not different between both groups. The IGP rate was significantly higher in male (43.3% vs 31.3%), in patients with perivesicular adhesions (17.75% vs 10.5%) and in patients with histologic diagnosis of acute cholecystitis (11.52% vs 4.92%). Operative time was significantly longer in patients with IGP (77.3 vs 65.4 minutes). Intraoperative drain and antibiotic use, as well as postoperative stay were, also, significantly higher in patients with IGP. There was not any late complication. Conclusión: Bile and gallstones spillage do not lead to an increase in surgical site infections, but is associated with an increased use of antibiotics and drains, longer operative time and longer postoperative stay.

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Resumen Objetivo: Evaluar la evolución de los niveles séricos de proteína C-reactiva y procalcitonina tras resección hepática. Materiales y Método: Estudio observacional prospectivo, con pacientes con diferentes tipos de resección hepática, sin infección ni complicaciones mayores posoperatorias. Los niveles de proteína C-reactiva y procalcitonina se midieron el día anterior a la cirugía y diariamente, hasta el 7° día, o hasta el alta, lo primero que ocurriera. Resultados: Se incluyeron 42 pacientes. Los niveles de procalcitonina, a las 24 h, correlacionaban significativamente con la duración de la operación (p = 0,04). A las 48 h, los niveles de proteína C-reactiva fueron mayores en las resecciones hepáticas no lobares que en las lobares (p = 0,049). A las 24 h, los niveles de procalcitonina aumentaron más en las hepatectomías mayores que en las menores (p = 0,017). Los niveles de procalcitonina fueron significativamente menores en los pacientes con abordaje laparoscópico en los 4 primeros días. Conclusión: La resección hepática produce un aumento de los niveles séricos de proteína C-reactiva y procalcitonina, pero con menor intensidad si el abordaje es laparoscópico. Los niveles séricos de proteína C-reactiva tienden a ser mayores en las hepatectomías menos extensas, mientras que los de procalcitonina tienden a ser mayores en las más extensas.

Aim: To evaluate the postoperative evolution of C-reactive protein and procalcitonin after hepatic resection. Materials and Method: Prospective observational study, including patients with different types of hepatic resection, without infectious or major postoperative complications. Procalcitonin and C-reactive protein serum levels were measured on the day prior to surgery and every day after surgery until the seventh postoperative day. Results: Forty-two patients were included. There was a significant correlation between procalcitonin levels at 24 hours after surgery and the overall length of surgery (p = 0.04). C-reactive protein was higher in nonlobar hepatectomies than in lobar hepatectomies 48 hours after surgery (p = 0.049). Procalcitonin was higher in major hepatectomies than in minor hepatectomies 24 hours after surgery (p = 0.017). Procalcitonin levels were significantly lower in patients with laparoscopic approach in the first four postoperative days. Conclusion: Hepatic resection increases the serum levels of C-reactive protein and procalcitonin, but with less intensity if the approach is laparoscopic. C-reactive protein levels tend to be higher in less extensive hepatectomies and procalcitonin levels tend to be higher in more extensive resections.

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Reptiles are important models for understanding fundamental aspects of physiological ecology and for assessing how environmental change can impact biodiversity. Abiotic factors (micro-environmental temperatures, operative temperatures, thermal quality) may vary geographically along an altitudinal and latitudinal gradient, and therefore the different thermal resources available for thermoregulation also vary. Comparative analyses among populations provide an opportunity to understand how variation in abiotic factors can affect different ecophysiological traits of a species at different geographical points. Our objective was to carry out a comparative study between two populations of Pristidactylus scapulatus in the Puna region of Argentina, providing the first data available on thermal ecophysiology, thermoregulatory efficiency and locomotor performance of the species. We determined field body temperature, micro-environmental temperatures and operative temperatures. In the laboratory, we measured preferred temperatures and calculated the index of thermoregulatory efficiency. In addition, we recorded critical temperature (minimum and maximum) and we estimated the thermal sensitivity of locomotion by measuring sprint speed at different body temperatures; based on these data we calculated the optimal temperature for performance, the optimal performance breadth and thermal safety margin. Air temperatures and operative temperatures were different between sites. However, we only found differences between populations in the minimum critical temperatures, with these being lower at higher latitude. We note that P. scapulatus populations adjust optimal temperatures of performance to field body temperatures and preferred temperatures, which could reduce the costs of thermoregulation in lizards with limited daily activity and who inhabit sites with variable and unpredictable environment temperatures. We conclude that Pristidactylus scapulatus has thermal sensitivity in locomotor performance, is a moderate thermoregulator with respect to the environment and is a eurithermic lizard, which has thermal flexibility in the cold.

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OBJECTIVE: Fructooligosaccharides (FOS) are prebiotic substances that have been extensively incorporated in different products of food industry mostly for their bifidogenic properties and economic value. The main commercial FOS production comes from the biotransformation of sucrose and intracellular and extracellular microbial enzymes-fructosyltransferases (FTase). Aspergillus oryzae IPT-301 produces FTase. In order to increase its production, this study focuses on evaluating the effects of different agitation speed and aeration rates which affect yields in a stirred tank bioreactor. RESULTS: Agitation had more influence on cell growth than aeration. The maximum intracellular FTase activity and the volumetric productivity of total intracellular FTase were obtained at 800 rpm and 0.75 vvm, and reached values of 2100 U g-1 and 667 U dm-3 h-1, respectively. The agitation speed had a strong influence on the activity of extracellular FTase produced which reached the maximum amount of 53 U cm-3. The higher value of total activity obtained was 22,831 U dm-3 at 0.75 vvm and 800 rpm. CONCLUSION: Aeration rates and agitation speed showed strong influence upon the growth and production of fructosyltransferase from Aspergillus oryzae IPT-301 in media containing sucrose as carbon source. The control of aeration rate and agitation speed can be a valuable fermentation strategy to improve enzyme production.

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OBJECTIVE: To evaluate the relationship between C reactive protein and procalcitonin levels and the appearance of post-operative intraabdominal infection, in patients with pancreaticoduodenectomy due to pancreatic cancer. METHOD: A prospective observational study, including 35 patients, was made. Procalcitonin and C reactive protein were measured before surgery, as well as 24, 48 and 72 h after the surgical procedure. Patients were divided in two groups, with and without intraabdominal infection. RESULTS: Six patients (17.1%) presented post-operative intraabdominal infection. Both, procalcitonin and C reactive protein, increased in all patients after surgery, but there were no significant differences between the two groups. However, the ratio between the C reactive protein concentrations on post-operative day 3 and the concentrations on post-operative day 1 was significantly increased in the group of patients with intraabdominal infection. The predictive positive value and the predictive negative value for this ratio were 60% and 95%, respectively, for a cut-off point of 2.3. CONCLUSIONS: The ratio between C reactive protein value on post-operative day 3 and the value on post-operative day 1 is a good predictor of post-operative intraabdominal infection after pancreaticoduodenectomy.

OBJETIVO: Evaluar la relación entre los valores de proteína C reactiva y de procalcitonina y la aparición de infección intraabdominal posoperatoria en pacientes con duodenopancreatectomía por cáncer de páncreas. MÉTODO: Estudio prospectivo observacional que incluye 35 pacientes. Ambos parámetros se midieron antes de la cirugía y a las 24, 48 y 72 horas de la intervención. Los pacientes se dividieron en dos grupos: con y sin infección intraabdominal. RESULTADOS: Seis pacientes (17.1%) tuvieron infección intraabdominal. Ambos parámetros aumentaron en todos los pacientes tras la cirugía, pero no hubo diferencias significativas entre los dos grupos. Sin embargo, el cociente entre los valores de proteína C reactiva en el día 3 y los valores en el día 1 de posoperatorio era significativamente mayor en los pacientes con infección intraabdominal, con un valor predictivo positivo del 60% y un valor predictivo negativo del 95%, para un punto de corte de 2.3. CONCLUSIONES: El cociente entre las concentraciones séricas de proteína C reactiva en el tercer día y en el primer día de posoperatorio es un buen predictor de infección intraabdominal posoperatoria después de una duodenopancreatectomía.

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Varón de 32 años que consulta por dos meses de palpitaciones episódicas en los últimos dos meses. El examen físico solo reveló extrasístoles aisladas. El ecocardiograma mostró que el miocardio no era homogéneo en su contraste y definición, con diversas imágenes de trabeculación y anfractuosidades o grietas en el miocardio de las paredes del ventrículo izquierdo, engrosamiento del subendocardio a nivel del segmento no compacto: y, el eco-Doppler a color mostró la penetración sanguínea dentro de las anfractuosidades. Estos signos fueron compatibles con un miocardio no compacto o espongiforme, por lo que se revisa la literatura a propósito de este inusual caso.

A 32 year-old male consulted because of episodic palpitations in the past two months. The physical examination revealed only isolated premature ventricular contractions. The Echocardiogram showed that the myocardium was not homogeneous in its contrast and sharpness with various images of trabeculation and fissures in the myocardium walls of the left ventricle, thickening of the subendocardial wall at the noncompaction segment; and, color Doppler eco showed blood penetration into the fissures. These signs were compatible with a non-compaction or spongiform cardiomyopathy, so a review the of the literature with regard to this unusual case was done.

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The ArCIS-UNR® arsenic and fluoride removal system which consists of a coagulation-adsorption process with initial pH adjustment and two filtration stages (up-flow gravel roughing filtration and rapid filtration), has been already described in previous studies. This process has been successfully implemented in full-scale plants in Argentina, with fluoride and total arsenic concentrations in raw water up to 2 mg/L and 200 µg/L, respectively. The aim of the present study is to optimize fluoride removal when it is >2.0 mg/L. The modifications proposed were to decrease the pH level to 6.4-6.6 at the roughing filter inlet and increase the pH level to 7.2-7.6 at the rapid filter inlet to decrease residual aluminum concentration. Laboratory and pilot scale studies were performed using natural water with fluoride concentrations ranging from 2.4 to 3.2 mg/L and arsenic concentrations from 60 to 90 µg/L. An optimal combination of operational parameters and the coagulant dose (polyaluminum chloride, PACl) was found, to achieve final concentrations of fluoride, arsenic and aluminum in treated water lower than those set by the regulations in force. Filtration run time was 10 to 12 hours; research studies are necessary to extend this period.

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RESUMEN La Autoridad Reguladora de Cuba lleva a cabo un programa de fomento y desarrollo de la cultura de seguridad radiológica en el país dada la reconocida contribución que tiene el factor humano en la ocurrencia de sucesos radiológicos. El programa incluye nuevas prácticas e iniciativas reguladoras para elevar el nivel de cultura de seguridad en Cuba como la reciente implementación de un método de trabajo denominado Sistema de Análisis, Diseminación y Aprendizaje de Sucesos e Incidentes Radiológicos (ADASIR), cuyo objetivo es incrementar el conocimiento sobre los sucesos ocurridos dentro o fuera del país para evitar su repetición en el territorio nacional. Expertos nacionales y de la Autoridad Reguladora realizan un pormenorizado análisis de esos eventos, identificando posibles causas raíces, barreras falladas y otros datos de interés nacional. Los resultados del debate son documentados y enviados a entidades, autoridades y organizaciones profesionales acompañados de una lista de chequeo para la autoevaluación institucional. El presente trabajo expone en detalle las características y los resultados de esta novedosa experiencia de la Autoridad Reguladora cubana.

ABSTRACT The Cuban Regulatory Authority is carrying out a National Program intended to foster and develop a Safety Culture taking into account the wide recognition of the human factors contribution to radiological events. The program includes the introduction of new regulatory practices and initiatives in order to increase the safety culture in Cuban facilities. The most recent of those initiatives is the System for Radiological Event Analysis, Dissemination and Learning, called ADASIR (acronym for the System’s name in Spanish). The main purpose of this system is to provide a better understanding and knowledge of any radiological event reported both in the country and abroad, thus reducing the possibility of occurrence of a similar event in our facilities. A team of regulatory and external experts make together a detailed review of all available information on the event and identify possible root causes, failed barriers and other important data of national interest. The results of such review are documented and sent to any Cuban facilities or organizations where these events can occur, considering the equipment and practices they have. The document includes an specific checklist which could be used by the facilities to make a self-assessment and evaluate their strength and weakness to similar events. This paper presents the main characteristics and results of this new experience of Cuban Regulatory Authority.

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RESUMEN El trabajo presenta los resultados del Análisis Probabilista de Seguridad al proceso de tratamiento de radioterapia con un acelerador lineal de uso médico desarrollado por el Foro Iberoamericano de Organismos Reguladores Radiológicos y Nucleares. Se evaluaron las exposiciones accidentales potenciales durante el proceso de tratamiento del paciente, los trabajadores y miembros del público, aunque el énfasis del estudio se orientó hacia los pacientes. El método de análisis de modos de fallos y efectos se utilizó para definir los sucesos iniciadores de accidentes y los métodos de árboles de sucesos y árboles de fallo para determinar las secuencias accidentales que se pueden producir. Una vez cuantificada la frecuencia de ocurrencia de las secuencias accidentales se realizaron análisis de importancia para determinar los sucesos más significativos desde el punto de vista de la seguridad y se identificaron los principales contribuyentes al riesgo, así como las recomendaciones de seguridad más apropiadas para reducirlo.

ABSTRACT This paper presents the results of the Probabilistic Safety Assessment to the radiotherapy treatment with an Electron Linear Accelerator for Medical Use, which was conducted in the framework of the Iberian-American Forum of Radiological and Nuclear Regulatory Agencies. Potential accidental exposures during the treatment of patients, workers and members of the public were assessed, although the study was mainly focused on patients. The methodology of failure modes and effects analysis was used to define accident initiating events and methods of event tree and fault tree analysis to determine the accident sequences that may occur. After quantifying the frequency of occurrence of the accident sequences, an important analysis was carried out in order to determine the most significant events from the point of view of safety. The major contributors to risk were identified as well as the most appropriate safety recommendations to reduce it.

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The role of quorum sensing (QS) in the response of Pseudomonas aeruginosa to UVA radiation was investigated in the PAO1 strain and derivatives defective in the synthesis of the QS signals 3OC12-HSL (lasI strain), C4-HSL (rhlI strain) or both (lasI rhlI strain). Cell viability measurements demonstrated that the double mutant was significantly more sensitive to UVA than single mutants, which in turn showed reduced cell survival with regard to the PAO1 strain. Irradiation under nitrogen atmosphere and chemiluminescence measurements indicated the oxidative nature of the UVA-induced damage. The activity of the antioxidant enzymes catalase and superoxide dismutase was assayed in these strains before and after irradiation, and a strong correlation between catalase levels and UVA sensitivity was observed. When a sublethal UVA dose was applied to PAO1, a growth delay was observed and this mechanism depended on the rhl system. Moreover, low doses of UVA irradiation triplicated the level of C4-HSL in log PAO1 cells. It is concluded that QS is fundamental in the defense against the toxic effects of UVA in P. aeruginosa. The induction of the QS system by UVA independently of cell density could function as an adaptative strategy to withstand this hostile environmental condition.

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Aspergillus oryzae IPT-301, previously reported as a ¥â-fructofuranosidase producing microorganism, was successfully mutated using UV irradiation at 253.7 nm followed by the screening of survivors resistant to certain stress conditions. Strains were first subjected to the ¥â-fructofuranosidase activity assay using a portion from the colony grown in Petri dish as the enzyme source. Seven mutants with fructofuranosidase activity values relative to the parent culture between 140 -190 percent were selected from survivors grown at temperature of 40¨¬C or 0.018 percent (w/v) sodium dodecyl sulfate concentration. They were cultivated on a rotary shaker to characterize mycelium and extracellular fructosyltransferase activities. Three mutants named IPT-745, IPT-746 and IPT-748 showed the highest amount of mycelium activity whose values increased 1.5 -1.8 fold, compared with the parent strain. It was found that more than 55 percent of total enzyme activity (mycelium- plus extracellular- activity) from these strains was detected in the mycelium fraction. Only one mutant, IPT-747, exceeded the amount of extracellular enzyme exhibited by the parent strain (1.5 times). This mutant also showed the highest value of total fructosyltransferase activity.

Asunto(s)

RESUMEN

Aspergillus oryzae IPT-301, previously reported as a ß-fructofuranosidase producing microorganism, was successfully mutated using UV irradiation at 253.7 nm followed by the screening of survivors resistant to certain stress conditions. Strains were first subjected to the ß-fructofuranosidase activity assay using a portion from the colony grown in Petri dish as the enzyme source. Seven mutants with ß-fructofuranosidase activity values relative to the parent culture between 140 - 190% were selected from survivors grown at temperature of 40ºC or 0.018% (w/v) sodium dodecyl sulfate concentration. They were cultivated on a rotary shaker to characterize mycelium and extracellular fructosyltransferase activities. Three mutants named IPT-745, IPT-746 and IPT-748 showed the highest amount of mycelium activity whose values increased 1.5 - 1.8 fold, compared with the parent strain. It was found that more than 55% of total enzyme activity (mycelium- plus extracellular- activity) from these strains was detected in the mycelium fraction. Only one mutant, IPT-747, exceeded the amount of extracellular enzyme exhibited by the parent strain (1.5 times). This mutant also showed the highest value of total fructosyltransferase activity.

RESUMEN

Aspergillus oryzae IPT-301, previously reported as a -fructofuranosidase producing microorganism, was successfully mutated using UV irradiation at 253.7 nm followed by the screening of survivors resistant to certain stress conditions. Strains were first subjected to the -fructofuranosidase activity assay using a portion from the colony grown in Petri dish as the enzyme source. Seven mutants with fructofuranosidase activity values relative to the parent culture between 140 -190% were selected from survivors grown at temperature of 40ºC or 0.018% (w/v) sodium dodecyl sulfate concentration. They were cultivated on a rotary shaker to characterize mycelium and extracellular fructosyltransferase activities. Three mutants named IPT-745, IPT-746 and IPT-748 showed the highest amount of mycelium activity whose values increased 1.5 -1.8 fold, compared with the parent strain. It was found that more than 55% of total enzyme activity (mycelium- plus extracellular- activity) from these strains was detected in the mycelium fraction. Only one mutant, IPT-747, exceeded the amount of extracellular enzyme exhibited by the parent strain (1.5 times). This mutant also showed the highest value of total fructosyltransferase activity.

RESUMEN

Seventeen different strains of filamentous fungi were grown in batch cultures to compare their abilities for the production of beta-fructofuranosidase. Three of them, Aspergillus oryzae IPT-301, Aspergillus niger ATCC 20611 and strain IPT-615, showed high production with total fructosyltransferase activity higher than 12,500 units l(-1). In addition, the beta-fructofuranosidases of those strains have a high fructosyltransferase activity-to-hydrolytic activity ratio. The temperature and pH effects on the sucrose-beta-fructofuranosidase reaction rate were studied using a 2(2) factorial experimental design. The comparative analysis of the tested variable coefficients shows that the variable pH contributes mostly to the changes in the fructosyltransferase and hydrolytic rates and in the V (t)/V (h) ratio. At 40 and 50 degrees C, there were no significant differences between the fructosyltransferase and hydrolytic velocities of these enzymes.

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