A new series of acylhydrazones derived from metribuzin with modulated herbicidal activity.

This paper reports the preparation and herbicidal evaluation of a small library of acylhydrazones based on the synthetic herbicide metribuzin. The hydrazone linkage easily obtained by reaction of metribuzin with aliphatic and aromatic aldehydes, masks efficiently the exocyclic amino group, thereby altering significantly H-bonding with the receptor and increasing the lipophilicity relative to the parent herbicide. The structures of all compounds, including key stereochemical issues on conformation and E/Z configuration around the C[bond, double bond]N bond were thoroughly elucidated by spectroscopic methods, and unambiguously corroborated by X-ray diffraction analysis. The herbicidal assays using an aliphatic and an aromatic acylhydrazone were performed on tomato and rapeseed plants grown in greenhouse. Our results demonstrate, regardless of rate application, that such acylhydrazone formulations do not alter the selectivity of metribuzin. Moreover, the herbicide activity was even higher in the alkyl derivative than that achieved by commercial metribuzin, thus suggesting that this substance can be applied with no need of combination with chemical coadjuvants, unlike most formulations of commercially available herbicides. Therefore, the study shows the promising effect of chemical derivatization of a common herbicide as metribuzin, to improve the herbicide activity without compromising selectivity, and allowing the farmers its use in crop protection safely and effectively.

Tumor de Wilms en displasia renal multiquística

RESUMEN Introducción: La displasia renal multiquística es una anomalía congénita caracterizada por un riñón afuncional con quistes de diferentes tamaños. Es considerada como una anomalía del desarrollo, aunque se han descrito casos hereditarios. Se ha puntualizado la degeneración maligna de esta displasia, pero su asociación es muy rara. Objetivo: Describir una paciente con tumor de Wilms asociado a una displasia renal multiquística. Presentación del caso: Paciente de sexo femenino y 10 años de edad que los ultrasonidos prenatales no detectaron anomalías del tracto urinario y a los 7 años un estudio ecográfico detectó quistes en el riñón izquierdo. No cumplió el seguimiento clínico y ultrasonográfico indicado y abandonó la consulta; los 10 años asistió al médico por síntomas respiratorios agudos y al palpar el abdomen se comprobó masa en flanco izquierdo de consistencia leñosa, no dolorosa y con contacto lumbar. Se realizó biopsia renal y se diagnosticó tumor de Wilms, se impuso tratamiento citostático y se realizó nefrectomía que confirmó el diagnóstico. Entre los antecedentes familiares se informa un hermano fallecido antes de las 72 horas de nacido por displasia renal multiquística bilateral y madre con nefropatía por reflujo vesicoureteral. Conclusiones: La paciente que se describe reúne tres características raras: un tumor maligno asociado a una displasia renal multiquística, la posibilidad hereditaria por el antecedente del hermano con la displasia bilateral y un tumor de Wilms a los 10 años de edad, lo que demuestra la importancia del seguimiento en estos pacientes.

ABSTRACT Introduction: Multicystic renal dysplasia is a congenital anomaly characterized by an afunctional kidney with cysts of different sizes. It is considered a developmental abnormality, although hereditary cases have been described. The malignant degeneration of this dysplasia has been pointed out, but its association is very rare. Objective: Describe a patient with Wilms tumor associated with multicystic renal dysplasia. Case Presentation: 10-year-old female patient to whom prenatal ultrasounds did not detect urinary tract abnormalities and at age 7 an ultrasound study detected cysts in the left kidney. She did not comply with the indicated clinical and ultrasonographic follow-up and left the consultation; at 10 years old, she attended the doctor for acute respiratory symptoms and when palpating the abdomen there was a mass on the left flank of woody consistency, not painful and with lumbar contact. A renal biopsy was conducted and Wilms tumor was diagnosed; cytostatic treatment was indicated, and a nephrectomy was performed that confirmed the diagnosis. Among the family history is reported a brother who died before 72 hours of birth due to bilateral multicystic renal dysplasia and a mother with nephropathy by vesicoureteral reflux. Conclusions: The described patient has three rare characteristics: a malignant tumor associated with multicystic renal dysplasia, the hereditary possibility due to the sibling's history of bilateral dysplasia, and a Wilms tumor at 10 years of age, which demonstrates the importance of follow-up in these patients.

Comportamiento diurno de cetáceos en el Área de Conservación Guanacaste, Costa Rica

Introducción: Tres especies de cetáceos, el delfín manchado pantropical (Stenella attenuata attenuata), el delfín nariz de botella (Tursiops truncatus) y la ballena jorobada (Megaptera novaeangliae) son un componente importante de la fauna marina del Área de Conservación Guanacaste. Sin embargo, la información biológica básica sobre el comportamiento y la presencia de estas especies sigue siendo escasa. Objetivo: El objetivo de este estudio es determinar el comportamiento diurno de los cetáceos en el sector marino de la ACG y en sus áreas adyacentes. Métodos: Se muestreó el Pacífico norte de Costa Rica desde Bahía Salinas hasta las Islas Murciélago, incluyendo el Golfo de Santa Elena, entre mayo de 2005 y mayo de 2006. Se utilizó el método de escaneo de comportamiento para identificar el comportamiento general de los grupos. Resultados: Se registraron encuentros para tres especies en un total de 36 avistamientos, pero solo con un tiempo considerable para dos especies, S. attenuata y M. novaeangliae. Los delfines manchados exhibieron una amplia variedad de comportamientos en la temporada de lluvias. La búsqueda de alimento (X2 = 29.42; g.l. = 1; P < 0.001) y los viajes (X2 = 38.33; g.l. = 1; P < 0.001) aumentaron significativamente en la época de lluvias. Los comportamientos predominantes para la ballena jorobada fueron la asociación madre-cría, social y de viaje; este último fue mayor en la época de lluvias (X2 = 78.16; g.l. = 1; P < 0.001). Conclusiones: En la zona, los cetáceos presentaron comportamientos como forrajeo y madre-cría, lo que significa que el área puede clasificarse como un hábitat crítico para estas especies de cetáceos, de mayor importancia para especies altamente migratorias como las ballenas jorobadas.

Introduction: Three species of cetaceans, the pantropical spotted dolphin (Stenella attenuata attenuata), the bottlenose dolphin (Tursiops truncatus) and the humpback whale (Megaptera novaeangliae), are important components of the marine fauna of the Guanacaste Conservation Area (ACG). However, basic biological information on the behavior and occurrence of these species remains scarce. Objective: The objective of this study is to determine the diurnal behavior of the three-mentioned species in the ACG. Methods: The north Pacific of Costa Rica, from Bahía Salinas to the Marine Sector of ACG was sampled between May 2005 and May 2006. The behavior scanning method was used to identify the general behavior of the cetacean groups. Results: Encounters were recorded for the three species, in a total of 36 sightings, but only for S. attenuata and M. novaeangliae for considerable periods of time. Stenella attenuata exhibited a wide variety of behaviors, being foraging (X2 = 29.42; d.f. = 1; P < 0.001) and travelling (X2 = 38.33; d.f. = 1; P < 0.001) significantly higher during the rainy season. Predominant behaviors for the humpback whale were mother-calf association, social and travelling; being the latter higher during the rainy season (X2 = 78.16; d.f. = 1; P < 0.001). Conclusions: Behaviors such as foraging and mother-calf were the most representative among species and the most frequent. This suggests that the area can be considered as a critical habitat for these species of cetaceans, with particular importance for highly migratory species such as humpback whales.

Impact of mid Eocene greenhouse warming on America's southernmost floras.

A major climate shift took place about 40 Myr ago-the Middle Eocene Climatic Optimum or MECO-triggered by a significant rise of atmospheric CO2 concentrations. The biotic response to this MECO is well documented in the marine realm, but poorly explored in adjacent landmasses. Here, we quantify the response of the floras from America's southernmost latitudes based on the analysis of terrestrially derived spores and pollen grains from the mid-late Eocene (~46-34 Myr) of southern Patagonia. Robust nonparametric estimators indicate that floras in southern Patagonia were in average ~40% more diverse during the MECO than pre-MECO and post-MECO intervals. The high atmospheric CO2 and increasing temperatures may have favored the combination of neotropical migrants with Gondwanan species, explaining in part the high diversity that we observed during the MECO. Our reconstructed biota reflects a greenhouse world and offers a climatic and ecological deep time scenario of an ice-free sub-Antarctic realm.

Brown bear communication hubs: patterns and correlates of tree rubbing and pedal marking at a long-term marking site.

Chemical communication is important for many species of mammals. Male brown bears, Ursus arctos, mark trees with a secretion from glands located on their back. The recent discovery of pedal glands and pedal-marking at a site used for tree-rubbing led us to hypothesize that both types of marking form part of a more complex communication system. We describe the patterns of chemical communication used by different age and sex classes, including differences in the roles of these classes as information providers or receivers over four years at a long-term marking site. Using video recordings from a camera trap, we registered a total of 285 bear-visits and 419 behavioral events associated with chemical communication. Bears visited the site more frequently during the mating season, during which communication behaviors were more frequent. A typical visit by male bears consisted of sniffing the depressions where animals pedal mark, performing pedal-marking, sniffing the tree, and, finally, rubbing against the trunk of the tree. Adult males performed most pedal- and tree-marking (95% and 66% of the cases, respectively). Males pedal-marked and tree-rubbed in 81% and 48% of their visits and sniffed the pedal marks and the tree in 23% and 59% of visits, respectively. Adult females never pedal marked, and juveniles did so at very low frequencies. Females rubbed against the tree in just 9% of their visits; they sniffed the tree and the pedal marks in 51% and 21% of their visits, respectively. All sex and age classes performed pedal- and tree-sniffing. There were significant associations between behaviors indicating that different behaviors tended to occur during the same visit and were more likely if another individual had recently visited. These associations leading to repeated marking of the site can promote the establishment of long-term marking sites. Marking sites defined by trees and the trails leading to them seem to act as communication hubs that brown bears use to share and obtain important information at population level.

How the environmental fate of clomazone in rice fields is influenced by amendment with olive-mill waste under different regimes of irrigation and tillage.

BACKGROUND: Irrigation and tillage systems alone or in combination with organic amendments can strongly influence soil properties, which in turn may also modify the environmental fate of any pesticides applied. This study was aimed at determining how amendment with composted olive-mill waste (W) influenced leaching, sorption, and persistence of the herbicide clomazone in rice field soils under different tillage and irrigation management practices. The field trial conducted covered 3 years in succession, with six treatments: irrigation by sprinkler and conventional tillage without (ST) or with W application (80 Mg ha-1 ) (STW), irrigation by sprinkler but no tillage (SNT), irrigation by sprinkler but no tillage with W application (SNTW), and continuous flooding irrigation and tillage without (FT) and with W application (FTW). RESULTS: Application of W significantly increased the adsorption of clomazone to soil in the first and third years. In the first year, the persistence of clomazone under aerobic (t1/2  = 33.1-36.3 days) and anaerobic incubation conditions (t1/2  = 3.43-10.8 days) decreased after W application to t1/2 values in the ranges 18.1-29.7 and 3.06-5.44 days, respectively. However, in the third year, although clomazone persistence increased significantly in SNT and ST when W was applied under both incubation conditions, it decreased significantly in FT management under anaerobic incubation conditions. The addition of W led to less leaching of clomazone, particularly for the FT case where the herbicide leaching losses were 2.8 and 2.6 times lower in the first and third years after W addition, respectively. CONCLUSIONS: Using W as an organic amendment could be regarded as an invaluable strategy to reduce water contamination by clomazone in rice production, especially under traditional tillage and flooding management. © 2019 Society of Chemical Industry.

Environmental fate of bensulfuron-methyl and MCPA in aerobic and anaerobic rice-cropping systems.

Bensulfuron-methyl (BM) and 4-chloro-2-methylphenoxyacetic acid (MCPA) are herbicides widely used in rice agroecosystems, and are commonly found in their environments, especially in water resources. The objective of this study was to evaluate the sorption-desorption, leaching, and dissipation of BM and MCPA under aerobic and anaerobic rice cropping conditions. For this purpose, a three-year field experiment was conducted in SW Spain using four management systems: aerobic with sprinkler irrigation and tillage (ST), sprinkler irrigation and no-tillage (SNT), long-term sprinkler irrigation and no-tillage (SNTLT), and anaerobic with flooding and tillage (FT). At the end of the experiment, the partition coefficients (Kd-values) in ST were (2.7, 3.1, and 3.9) and (1.2, 1.5, and 1.9) times significantly lower than the values in {SNT, SNTLT, and FT} for BM and MCPA, respectively. Greater sorption was related to lower values of soil pH for both herbicides and to higher contents in humic acids for BM and fulvic acids for MCPA. The persistence was much longer for BM (t1/2 = 26.9-52.1 days) than for MCPA (t1/2 = 1.54-21.1 days) in all management systems, and both herbicides' dissipation rates were generally greater under aerobic than under anaerobic conditions. The mobility of MCPA was much greater than that of BM. Compared with SNT and SNTLT, leaching losses of the applied BM were greater by 51% for ST, and of the applied MCPA by 55% and 99% for ST and FT, respectively. Therefore, only aerobic rice production with no-tillage in the short- or long-terms could be considered as alternative management strategies with which to reduce water contamination by BM and MCPA in rice-growing environments.

A Training Program in Working Alliance Communication Skills.

The current paper presents the results from two studies. The first study examined the effectiveness of a training program designed to enhance medical residents' working alliance communication skills. The second study surveyed patients to examine if the resident training program resulted in significantly improved adherence and satisfaction for their patients. The first study used an experimental design, and 104 residents were randomly assigned to one of two groups: one group received working alliance training and the other served as a control and received no training. In the second study, after the training was completed, we surveyed one patient treated by each of the residents who participated in the first study to assess differences by resident group on patient self-reported adherence and satisfaction. In all, 68 patients participated and these patients were blind to whether the resident had participated in the training. For the first study, post-test data for the two groups showed that residents in the training group reported higher working alliance skills than residents in the control group. For the second study, patients cared for by residents who participated in the training reported better adherence and higher satisfaction with treatment than patients of residents in the control group. Thus, the training program appears to enhance residents' working alliance communication skills and is related to self-reported improvement in patient adherence and satisfaction. Further research is warranted to better understand these findings.

Tumor estromal gastrointestinal / Gastrointestinal stromal tumor

Introducción: el tumor estromal gastrointestinal es un raro tumor pediátrico que asienta generalmente en estómago en el 50 % de los casos, seguida de su localización en intestino delgado. En el intestino grueso es más rara, al igual que en esófago. Puede ir desde una forma benigna a una forma maligna de la enfermedad. Existe una gran cantidad de factores predisponentes, pero se le concede gran valor a la predisposición hereditaria y a las mutaciones, y también se asocia a la neurofibromatosis tipo 1. Se manifiesta clínicamente con sangrado digestivo oculto, anemia y vómitos. Se describen molestias digestivas y dolor abdominal.Presentación del caso: se presenta a la comunidad médica el caso de un paciente masculino, de 15 años de edad, mestizo, con un tumor estromal en la pared gástrica posterior al nivel de la curvatura mayor, muy cerca del píloro. El tumor fue resecado quirúrgicamente mediante laparotomía, pero el diagnóstico inicial y toma de biopsia se realizó por vía de cirugía de mínimo acceso. El paciente actualmente está bajo vigilancia estrecha.Conclusión: existen pocos casos publicados de tumor estromal gastrointestinal en Pediatría y se resalta la importancia de la cirugía en el control de la enfermedad(AU)

Ecology and management of the invasive lionfish Pterois volitans/miles complex (Perciformes: Scorpaenidae) in Southern Costa Rica.

Invasive species alter ecosystem integrity and functioning and are considered one of the major threats to biodiversity on a global scale. The indopacific lionfish (Plerois volitans [Linnaeus, 1758] / miles [Bennet, 1882] complex) is the first non-native marine fish that has established itself in the Western Atlantic. It was first reported in Florida in the 1980s and then spread across the entire Caribbean in subsequent years. In Costa Rica, lionfish were first sighted by the end of 2008 and are now present in all South Caribbean reefs. Lionfish are a major problem for local fisherman by displacing native fish species. The aim of this study was to determine population density, size and diet of lionfish populations at four study sites along the Southern Caribbean coast of Costa Rica. Two of the sites were located inside the National Park Cahuita where regular lionfish removal occurs, whereas the other two study sides do not experiment this kind of management. Total length and wet weight of >450 lionfish individuals were determined between March and June 2011. Three relative metrics of prey quantity (percent number, percent frequency, and percent weight) were compared from approximately 300 lionfish caught with the polespear in shallow waters (<7 m depth). Population density was assessed weekly through visual transect surveys. Our results showed that lionfish preyed mostly upon teleosts and crustaceans. Teleosts dominated lionfish diet in percent frequency (71%) and percent weight (85%), whereas crustaceans had the highest percent number (58%). The top five teleost families of dietary importance were Pomacentridae, Acanthuridae, Blennidae, Labridae and Serranidae. The average total length (+/- SD) of lionfish was 18.7 (+/- 5.7)cm and varied significantly between sites (p<0.001). Mean density of lionfish was 92fish/ha with no significant differences between sites. Smallest fish and lowest densities were found at the two sites inside the National Park Cahuita. Despite management efforts on a regional scale, nationwide efforts are ineffective and lionfish control activities are poorly implemented. We conclude that there is an urgent need to develop an improved institutional framework for local lionfish control that promotes effective coordination among the relevant stakeholders in order to deal with invasive lionfish in Costa Rica.

Agregación costera de tortugas marinas en aguas del Pacífico Sur de Costa Rica / Coastal aggregation of marine turtles in waters of the South Pacific of Costa Rica

Resumen El Pacífico Sur de Costa Rica ha sido identificado como un sitio importante para la reproducción de cuatro especies de tortugas marinas. Las amenazas que éstas sufren han originado iniciativas de conservación y estudio en la zona, especialmente en playas de anidación. Sin embargo, información sobre su presencia en el agua (donde pasan la mayor parte de su vida) es escasa. Por esta razón, este estudio analiza la información recolectada como parte de un proyecto de monitoreo de tortugas marinas de la Fundación Keto, en la zona comprendida entre el Parque Nacional Marino Ballena y la Reserva Biológica Isla del Caño. Entre los años 2009 y 2011, se registraron 447 avistamientos de tortugas (la mayoría fuera de las áreas de conservación) pertenecientes a tres especies: Lepidochelys olivacea, Chelonia mydas, y Eretmochelys imbricata. Se registraron avistamientos durante todos los meses del año, siendo L. olivacea la especie con más individuos observados. Se identificaron dos áreas (a profundidades menores a 10m) importantes para la presencia de E. imbricata. Este es el primer aporte científico que documenta la presencia exacta, considerable y continua en el tiempo de tres especies de tortugas marinas frente a las costas del Cantón de Osa, Puntarenas, Costa Rica.

Abstract The southern Pacific coast of Costa Rica has been identified as an important place for the reproduction of four species of marine turtles. This presence, coupled with threats to the survival of the species, has encouraged the establishment of conservation initiatives and the study of these animals in the region, especially in nesting areas. Nonetheless, information on their presence in the water (where they spend most of their life) is scarce. For this reason, this study analyses data from a three years of a marine turtle monitoring program by Fundación Keto in the area between the Marino Ballena National Park and the Caño Island Biological Reserve, and presents the temporal and spatial distribution of the observed individuals. During this period, a total of 447 turtle (sightings per sampling effort=0.36 individuals-hr-1), of three different species were observed: Lepidochelys olivacea, Chelonia Mydas, and Eretmochelys imbricata. Sightings have been recorded during all months of the year, with L. olivacea as the species most commonly observed, especially outside of protected areas; this species presented a clear mating period in the months of July and August. E. imbricata was the species observed closer to the shore, and at a shallower site, possibly indicating an important foraging area for juvenile individuals. This is the first study to address the consistent and permanent presence of three species of marine turtles in the waters off the coast of Cantón de Osa in the southern Pacific coast of Costa Rica. Rev. Biol. Trop. 63 (Suppl. 1): 1-8. Epub 2015 April 01.

Ecology and management of the invasive lionfish Pterois volitans/miles complex (Perciformes: Scorpaenidae) in Southern Costa Rica / Ecología y manejo del pez león Pterois volitans/miles complex (Perciformes: Scorpanidae) en el Caribe sur de Costa Rica

Invasive species alter ecosystem integrity and functioning and are considered one of the major threats to biodiversity on a global scale. The indopacific lionfish (Pterois volitans [Linnaeus, 1758] / miles [Bennet, 1882] complex) is the first non-native marine fish that has established itself in the Western Atlantic. It was first reported in Florida in the 1980s and then spread across the entire Caribbean in subsequent years. In Costa Rica, lionfish were first sighted by the end of 2008 and are now present in all South Caribbean reefs. Lionfish are a major problem for local fisherman by displacing native fish species. The aim of this study was to determine population density, size and diet of lionfish populations at four study sites along the Southern Caribbean coast of Costa Rica. Two of the sites were located inside the National Park Cahuita where regular lionfish removal occurs, whereas the other two study sides do not experiment this kind of management. Total length and wet weight of >450 lionfish individuals were determined between March and June 2011. Three relative metrics of prey quantity (percent number, percent frequency, and percent weight) were compared from ~300 lionfish caught with the polespear in shallow waters (<7m depth). Population density was assessed weekly through visual transect surveys. Our results showed that lionfish preyed mostly upon teleosts and crustaceans. Teleosts dominated lionfish diet in percent frequency (71%) and percent weight (85%), whereas crustaceans had the highest percent number (58%). The top five teleost families of dietary importance were Pomacentridae, Acanthuridae, Blennidae, Labridae and Serranidae. The average total length (±SD) of lionfish was 18.7(±5.7)cm and varied significantly between sites (p<0.001). Mean density of lionfish was 92fish/ha with no significant differences between sites. Smallest fish and lowest densities were found at the two sites inside the National Park Cahuita. Despite management efforts on a regional scale, nationwide efforts are ineffective and lionfish control activities are poorly implemented. We conclude that there is an urgent need to develop an improved institutional framework for local lionfish control that promotes effective coordination among the relevant stakeholders in order to deal with invasive lionfish in Costa Rica.

Las especies invasoras alteran la integridad y el funcionamiento de los ecosistemas y se consideran una de las mayores amenazas para la biodiversidad a nivel global. El pez león (Pterois volitans [Linnaeus, 1758]/ miles [Bennet, 1882] complex) del Indo-Pacífico es el primer pez marino no-nativo que se ha establecido en el Atlántico oeste. Fue reportado por primera vez en Florida en los años 80´s y se propagó en todo el Caribe en los años subsiguientes. En Costa Rica, el pez león se reporto por primera vez a finales del 2008 y hoy en día se encuentra en todos los arrecifes del Caribe Sur. El pez león es un grave problema para los pescadores locales por desplazar a los recursos pesqueros nativos. El objetivo de este estudio fue determinar la densidad poblacional, talla y la dieta de las poblaciones del pez león en cuatro sitios de muestreo a lo largo de la costa del Caribe Sur de Costa Rica. Dos de los sitios fueron localizados dentro del Parque Nacional Cahuita donde se efectúan remociones periódicos del pez león, mientras que los otros dos sitios no experimenten este tipo de manejo. Se midieron la longitud total y el peso fresco de >450 individuos entre marzo y junio 2011. Se compararon tres medidas relativas para el análisis estomacal (composición por número, por frecuencia y por peso) de ~300 individuos capturados con un arpón marino en las aguas someras (<7m profundidad). La densidad poblacional fue estimada a partir de transectos visuales semanales. Nuestros resultados muestran que el pez león se alimentó principalmente de teleósteos y crustáceos. Los teleósteos dominaron la dieta en cuanto a composición por frecuencia (71%) y composición por peso (85%), mientras que los crustáceos prevalecieron en cuanto a composición por número (58%). Las cinco familias más importantes en la dieta del pez león fueron los Pomacentridae, Acanthuridae, Blennidae, Labridae y Serranidae. La longitud total media (±DE) fue 18.7(±5.7)cm y varió significativamente entre los sitios (p<0.001). La densidad media fue de 92 peces/ha y no fue estadísticamente diferente entre los sitios. Los peces con la menor talla y las densidades poblacionales más bajas fueron encontrados en los dos sitios dentro del Parque Nacional Cahuita. A pesar de los esfuerzos de manejo que existen a nivel regional, las estrategias nacionales son deficientes y las actividades para el control de la especie invasiva son escasos en Costa Rica. Es preciso desarrollar un marco institucional para el control local del pez león que incluye todo los implicados y que promueva la coordinación efectiva entre ellos.

Leiomioma gástrico / Gastric leiomyoma

El leiomioma gástrico es un tumor intramural, extramucoso, localizado, en la mayoría de los casos, en el tubo digestivo superior, a nivel del tercio distal del esófago y porción superior del estómago. Puede afectar ambos sexos, pero es muy raro en la edad pediátrica. Aumenta su incidencia a partir de la quinta y sexta década de la vida, y son de tamaño variable. Se presenta el caso de un paciente masculino, de 10 años de edad, blanco, con un leiomioma a nivel de la pared gástrica, que fue resuelto quirúrgicamente con resección completa de la masa tumoral que comprometía gran parte de la curvatura mayor gástrica mediante laparotomía, pero el diagnóstico inicial y toma de biopsia se realizó por vía endoscópica(AU)

Gastric leiomyoma is an intramural, extramucosal tumor that is mostly located in the upper digestive tube, at the distal third of the esophagus and the upper portion of the stomach. It may affect both sexes but it is very unusual at pediatric ages. Its incidence is higher from the 50 and 60 years of age on, with variable sizes. This is the case of a male 10 years-old Caucasian child, who had leiomyoma inside his gastric wall and was operated on through laparotomy to completely remove the tumor mass that endangered a large part of the major gastric curvature. The initial diagnosis and the biopsy were based on endoscopic procedures(AU)

Leiomioma gástrico / Gastric leiomyoma

El leiomioma gástrico es un tumor intramural, extramucoso, localizado, en la mayoría de los casos, en el tubo digestivo superior, a nivel del tercio distal del esófago y porción superior del estómago. Puede afectar ambos sexos, pero es muy raro en la edad pediátrica. Aumenta su incidencia a partir de la quinta y sexta década de la vida, y son de tamaño variable. Se presenta el caso de un paciente masculino, de 10 años de edad, blanco, con un leiomioma a nivel de la pared gástrica, que fue resuelto quirúrgicamente con resección completa de la masa tumoral que comprometía gran parte de la curvatura mayor gástrica mediante laparotomía, pero el diagnóstico inicial y toma de biopsia se realizó por vía endoscópica.

Gastric leiomyoma is an intramural, extramucosal tumor that is mostly located in the upper digestive tube, at the distal third of the esophagus and the upper portion of the stomach. It may affect both sexes but it is very unusual at pediatric ages. Its incidence is higher from the 50 and 60 years of age on, with variable sizes. This is the case of a male 10 years-old Caucasian child, who had leiomyoma inside his gastric wall and was operated on through laparotomy to completely remove the tumor mass that endangered a large part of the major gastric curvature. The initial diagnosis and the biopsy were based on endoscopic procedures.

Comparison of a Validated LC/MS/MS Method with a Validated GC/MS Method for the Analysis of Zeranol and its Related Mycotoxin Residues in Bovine Urine Samples Collected During Argentina's Residue Monitoring Control Program (2005-2012).

The use of zeranol (ZRL), a resorcylic acid lactone, in food animal production has been banned in Argentina since 2004. To enforce this regulation, a GC/MS method developed by the official laboratory was used to confirm ZRL, taleranol, and α- and ß-zearalenol from suspect samples. A few years later, a more sensitive LC/MS/MS method was also developed for testing these four analytes plus zearalenone. Both methods were validated according to local standards that are equivalent to 657/2002/EC, and the GC/MS method was accredited under ISO/International Electrotechnical Commission 17025. This paper describes the analytical methods, compares their performances, and presents conclusions derived from their results. When these methods were used on national control plans in which about 1262 samples were analyzed annually over the 2005-2011 sampling period, the incidence rate for noncompliant samples analyzed by GC/MS ranged from 0.3 to 4%. Of the 1500 samples analyzed in 2012 by both methods, the noncompliance incidence rate was only 0.3%.

[Inshore cetaceans from the North and South Pacific coast of Costa Rica]. / Cetáceos de las aguas costeras del Pacífico norte y sur de Costa Rica.

Twenty nine cetacean species occur in Costa Rican waters but extensive research has been conducted only for three species. The latter shows there is a lack of general and local information about these mammals, even when the country, has shown a remarkable growth in whale watching activities. The increasing use of marine resources in coastal areas has also developed the need to determine the occurrence of cetaceans in areas showing high tourist presence, in order to propose sound conservation measures. In this study, environmental variables were determined and subsequently related to the presence of the species recorded, out of 166 sightings, between 2005 and 2006. The species with highest proportion of sightings were Stenella attenuata (68%), followed by Megaptera novaeangliae (13%) and Tursiops truncatus (10%). The presence of spotted dolphins is related to changes in salinity and water transparency, while that of the humpback whale was related to wave height (Beaufort scale) and water temperature. The presence of seven species of cetaceans was confirmed in two coastal areas of the Pacific coast of Costa Rica, from which three are present throughout the year. Environmental variables were found related to the presence of at least two species.

Cetáceos de las aguas costeras del Pacífico norte y sur de Costa Rica

Inshore cetaceans from the North and South Pacific coast of Costa Rica. Twenty nine cetacean species occur in Costa Rican waters but extensive research has been conducted only for three species. The latter shows there is a lack of general and local information about these mammals, even when the country, has shown a remarkable growth in whale watching activities. The increasing use of marine resources in coastal areas has also developed the need to determine the occurrence of cetaceans in areas showing high tourist presence, in order to propose sound conservation measures. In this study, environmental variables were determined and subsequently related to the presence of the species recorded, out of 166 sightings, between 2005 and 2006. The species with highest proportion of sightings were Stenella attenuata (68%), followed by Megaptera novaeangliae (13%) and Tursiops truncatus (10%). The presence of spotted dolphins is related to changes in salinity and water transparency, while that of the humpback whale was related to wave height (Beaufort scale) and water temperature. The presence of seven species of cetaceans was confirmed in two coastal areas of the Pacific coast of Costa Rica, from which three are present throughout the year. Environmental variables were found related to the presence of at least two species. Rev. Biol. Trop. 59 (1): 283-290. Epub 2011 March 01.

De las 29 especies de cetáceos presentes en Costa Rica, se han realizado investigaciones exhaustivas solamente para tres especies. Lo anterior evidencia la poca información general existente sobre cetáceos, a pesar de que Costa Rica posee un notable crecimiento de actividades de avistamiento. Debido al uso que se está generando en las zonas costeras, cada vez se hace más necesario determinar la ocurrencia de cetáceos en zonas de alta actividad turística, con el fin de proponer medidas de conservación. En el presente estudio, se determinaron variables ambientales que estaban relacionadas con la presencia de especies registradas, a partir de 166 avistamientos entre el 2005 y 2006. Las especies con mayor proporción de avistamientos fueron Stenella attenuata (68%), seguida por Megaptera novaeangliae (13%) y Tursiops truncatus (10%). La presencia del delfín manchado se relaciona con cambios de salinidad y trasparencia del agua, mientras que la de la ballena jorobada estuvo relacionada con el oleaje y la temperatura superficial del agua. Se confirma la presencia de 7 especies de cetáceos en dos zonas costeras del Pacífico de Costa Rica, de las cuales tres están presentes a lo largo del año. Se encontraron variables ambientales relacionadas con la presencia de al menos dos especies.

Conservación del ombusillo, planta amenazada de la provincia de Buenos Aires, Argentina / Conserving ombusillo, an endangered plant from the province of Buenos Aires, Argentina

Phytolacca tetramera Hauman "ombusillo", es una especie vegetal endémica del SE de la Provincia de Buenos Aires, Argentina, que se halla en peligro crítico de extinción. Su principal factor de amenaza es la reducción del hábitat por acción antrópica. Esta especie presenta principios activos fungicidas y, posiblemente, dada su afinidad con otras especies del mismo género, presente compuestos antivirales, antitumorales, bactericidas e insecticidas. Se realizaron ensayos de macropropagación con distintas concentraciones de reguladores de crecimiento de tipo auxínicos que muestran claramente un enraizamiento óptimo correspondiente a segmentos de ejes aéreos vegetales “estacas” sometidas a 300 ppm de ácido indol butírico y a segmentos de tallos subterráneos sin aplicación de hormonas. Así mismo, se realizaron ensayos de germinación, en condiciones de luz y de oscuridad, comprobándose que las semillas presentan fotoblastismo positivo con un porcentaje de germinación del 65%, el cual disminuye enormemente luego del año de cosecha.

Phytolacca tetramera Hauman "ombusillo" is an endemic plant species which is in critical danger of becoming extinct; it comes from the south-east of the province of Buenos Aires. The main factor threatening this species is the reduction of its natural environment by antropic action.This species has antifungal properties and, due to its relationship with other species from the same genus, it could also have antiviral, antitumour, antibacterial and insecticidal compounds. Macropropagation experiments were carried out using different concentrations of auxinic growth regulators. Segements of aerial axis “stakes” treated with 300 ppm of indol-butiric acid and segments of underground stems without hormonal treatment provided optimum rooting. Germination experiments in dark and light conditions were also carried out, finding that seeds showed positive photoblastisme with a 65% germination rate which declined considerably after the crop had been harvested.