Biomarcadores etológicos no invasivos de estrés ambiental: estudio comparativo en dos teleosteos de ecosistemas de la región pampeana argentina

Mediante un dispositivo de registro automático se estudió el efecto de la exposición a soluciones subletales de Cd2+ (0.3 mg. L'1) sobre algunos parámetros etológicos de juveniles de Cyprinus carpió (carpa común) y de Astyanax fasciatus (“mojarra”). Se evaluó el efecto del metal sobre la actividad natatoria total y las preferencias altitudinales y laterales de los peces. Los tres parámetros se registraron simultáneamente mediante un dispositivo original. Se evaluaron los niveles “normales” o estándar de dichos parámetros (los peces en agua potable, control) y los alcanzados por los mismos individuos tras su exposición al tóxico de referencia (Cd). El metal provocó una depresión de la actividad natatoria total alcanzando una magnitud comparable en ambas especies. La preferencia altitudinal, también resultó modificada: C. carpió se halló con mayor frecuencia en la capa superior de los acuarios mientras que A. fasciatus se ubicó en las inferiores. En cuanto a la preferencia lateral, los individuos de ambas especies evitaron la franja vertical donde se producía el goteo de la solución de Cd; si bien esta respuesta espacial de los animales no siguió un patrón definido fue más marcada en las carpas. Todas las respuestas se pusieron de manifiesto inmediatamente después de haberse iniciado la exposición al Cd. El método resultó sensible y apto para el seguimiento de los parámetros etológicos seleccionados. Se concluye que la actividad natatoria y la ubicación espacial de las especies estudiadas, entre otros indicadores, pueden ser considerados como biomarcadores de toxicidad acuática.By means of an automatic recording device, the eífects of the exposure to sublethal Solutions of Cd2+ (0.3 mg. L2) on some ethological parameters of juvenile Cyprinus carpió (common carp) and Astyanaxfasciatus. The effect of the metal was evaluated through three parameters: the total swimming activity and the spatial (lateral and altitudinal) preferences, relative to Controls (fish kept in tap water); they were registered simultaneously by means oían original device. There were determined successively the “normal” or standard levels of those parameters in control fish and those reached by the same individuáis aftertheir exposure to thereferencetoxic (Cd). In both species the metal caused a depression of the total swimming activity in a comparable magnitude. The altitudinal preference was also modified: C. carpió was found more frequently in the superior layer of the aquaria while A. fasciatus was found in the inferior ones. For the lateral preference, the individuáis of both species showed an avoidance behavior of the site of the aquaria where the Cd Solutions was dripping. This response of the animáis didn't follow a defined pattem, but was more marked in the carps. All the evaluated responses to the toxic were detected immediately after the beginning of the exposure to Cd. The method proved to be sensitive and apt for the monitoring of the measured behavioural parameters which makes it a promising tool for biomonitoring purposes. We concluded that the swimming activity and the spatial location preferences of the studied species, among other, may be considered as biomarkers of aquatic toxicity

Understanding the reasons behind the low utilisation of thrombolysis in stroke

Background Thrombolysis remains the only approved therapy for acute ischaemic stroke (AIS); however, its utilisation is reported to be low. Aims This study aimed to determine the reasons for the low utilisation of thrombolysis in clinical practice. Method Five metropolitan hospitals comprising two tertiary referral centres and three district hospitals conducted a retrospective, cross-sectional study. Researchers identified patients discharged with a principal diagnosis of AIS over a 12-month time period (July 2009-July 2010), and reviewed the medical record of systematically chosen samples. Results The research team reviewed a total of 521 records (48.8% females, mean age 74.4 ±14 years, age range 5-102 years) from the 1261 AIS patients. Sixty-nine per cent of AIS patients failed to meet eligibility criteria to receive thrombolysis because individuals arrived at the hospital later than 4.5 hours after the onset of symptoms. The factors found to be positively associated with late arrival included confusion at onset, absence of a witness at onset and waiting for improvement of symptoms. However, factors negatively associated with late arrival encompassed facial droop, slurred speech and immediately calling an ambulance. Only 14.7% of the patients arriving within 4.5 hours received thrombolysis. The main reasons for exclusion included such factors as rapidly improving symptoms (28.2%), minor symptoms (17.2%), patient receiving therapeutic anticoagulation (6.7%) and severe stroke (5.5%). Conclusion A late patient presentation represents the most significant barrier to utilising thrombolysis in the acute stroke setting. Thrombolysis continues to be currently underutilised in potentially eligible patients, and additional research is needed to identify more precise criteria for selecting patients for thrombolysis

Dual-Band Transmitter and Receiver with Bowtie-Antenna in 0.13 μm SiGe BiCMOS for Gas Spectroscopy at 222 - 270 GHz

This paper presents a transmitter (TX) and a receiver (RX) with bowtie-antenna and silicon lens for gas spectroscopy at 222-270 GHz, which are fabricated in IHP’s 0.13 μm SiGe BiCMOS technology. The TX and RX use two integrated local oscillators for 222 – 256 GHz and 250 – 270 GHz, which are switched for dual-band operation. Due to its directivity of about 27 dBi, the single integrated bowtie-antenna with silicon lens enables an EIRP of about 25 dBm for the TX, and therefore a considerably higher EIRP for the 2-band TX compared to previously reported systems. The double sideband noise temperature of the RX is 20,000 K (18.5 dB noise figure) as measured by the Y-factor method. Absorption spectroscopy of gaseous methanol is used as a measure for the performance of the gas spectroscopy system with TX- and RX-modules

Positive surgical margin during radical prostatectomy: overview of sampling methods for frozen sections and techniques for the secondary resection of the neurovascular bundles

Objective: The aim of the paper is to provide an overview of intraoperative sampling methods for frozen section (FS) analysis and of surgical techniques for a secondary neurovascular bundle (NVB) resection, as the method of surgical margin (SM) sampling and the management of a positive SM (PSM) at the nerve-sparing (NS) area are under evaluated issues. FS analysis during radical prostatectomy (RP) can help to tailor the plane of dissection based on cancer extension and thus extend the indications for NS surgery. Evidence Acquisition: We performed a PubMed/Medical Literature Analysis and Retrieval System Online (MEDLINE), Web of Science, Cochrane Library, and Elton B. Stephens Co. (EBSCO)host search to include articles published in the last decade, evaluating FS analysis in the NS area and surgical attempts to convert a PSM to a negative status. Evidence Synthesis: Overall, 19 papers met our inclusion criteria. The ways to collect samples for FS analysis included: systematic (analysing the whole posterolateral aspect of the prostate specimen, i.e., neurovascular structure-adjacent frozen-section examination [NeuroSAFE]); magnetic resonance imaging (MRI)-guided (biopsies from MRI-suspicious areas, retrieved by the surgeon in a cognitive way); and random biopsies from the soft periprostatic tissues. Techniques to address a PSM in the NS area included: full resection of the spared NVB, from its caudal to cranial aspect, often including the rectolateral part of the Denonvilliers’ fascia; partial resection of the NVB, in cases where sampling attempts to localise a PSM; incremental approach, meaning a partial or full resection that extends until no prostate tissue is found in the soft periprostatic environment. Conclusions: There is no homogeneity in prostate sampling for FS analysis, although most recent evidence is moving toward a systematic sampling of the entire NS area. The management of a PSM is variable and can be affected by the sampling strategy (difficult localisation of the persisting tumour at the NVB). The difficult identification of the exact soft tissue location contiguous to a PSM could be considered as the critical point of FS analysis and of spared-NVB management

Evaluación toxicológica no invasiva del cadmio: modificaciones de biomarcadores conductuales en <i>Cyprinus carpio</i>

Se describe un dispositivo que permite evaluar simultáneamente varios parámetros conductuales de peces en cautiverio. Se informan los resultados preliminares alcanzados al exponer juveniles (3-4 g) de la carpa común (Cyprinus carpio) a dos soluciones subletales de de Cd2+ (0.3 y 0.5 mg/L), determinándose los cambios en su actividad natatoria (expresada cuantitativamente mediante un Indice de actividad relativa, Ia) y en sus preferencias altitudinal y lateral en los acuarios. La actividad natatoria total se redujo significativamente a la concentración más elevada del metal, retornando a los niveles basales registrados en el período Control luego de transferir los peces a medio sin el metal. La preferencia altitudinal, resultó modificada, encontrándose que los peces expuestos al metal se hallaban la mayor cantidad de tiempo en la capa superior de los acuarios. En cuanto a la preferencia lateral el resultado más importante fue la evidencia de que los mismos peces evitaban la sección correspondiente al sitio de goteo de la solución de Cadmio, sin hallarse un patrón particular de distribución en el resto de las secciones de los acuarios. Los cambios en la actividad natatoria total y en la preferencia altitudinal de los peces fueron reversibles; en cambio, la alteración en la preferencia lateral no se modificó luego del reemplazo de las soluciones de Cd por medios limpios.Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) - Instituto de Limnología "Dr. Raul A. Ringuelet" (ILPLA

Evaluación toxicológica no invasiva del cadmio: modificaciones de biomarcadores conductuales en Cyprinus carpio

Se describe un dispositivo que permite evaluar simultáneamente varios parámetros conductuales de peces en cautiverio. Se informan los resultados preliminares alcanzados al exponer juveniles (3-4 g) de la carpa común (Cyprinus carpio) a dos soluciones subletales de de Cd2+ (0.3 y 0.5 mg/L), determinándose los cambios en su actividad natatoria (expresada cuantitativamente mediante un Indice de actividad relativa, Ia) y en sus preferencias altitudinal y lateral en los acuarios. La actividad natatoria total se redujo significativamente a la concentración más elevada del metal, retornando a los niveles basales registrados en el período Control luego de transferir los peces a medio sin el metal. La preferencia altitudinal, resultó modificada, encontrándose que los peces expuestos al metal se hallaban la mayor cantidad de tiempo en la capa superior de los acuarios. En cuanto a la preferencia lateral el resultado más importante fue la evidencia de que los mismos peces evitaban la sección correspondiente al sitio de goteo de la solución de Cadmio, sin hallarse un patrón particular de distribución en el resto de las secciones de los acuarios. Los cambios en la actividad natatoria total y en la preferencia altitudinal de los peces fueron reversibles; en cambio, la alteración en la preferencia lateral no se modificó luego del reemplazo de las soluciones de Cd por medios limpios.Trabajo presentado en II Jornadas sobre Ecología y Manejo de Ecosistemas Acuáticos Pampeanos (EMEAP) (La Plata, 2002)

Cambios en la velocidad de nado como indicador del efecto tóxico del cadmio en Astyanax fasciatus y Australoheros facetum

Numerous studies have shown that the swimming performance parameters of fish may be useful indicators of their environmental stress. The swimming speed was evaluated in two Pampean species and its alteration as a result of their exposure to sublethal Cadmium concentrations. The swimming speed was calculated from a daily registry of the distance and the time of displacement of fish by means of special software. Juveniles specimens of Astyanax fasciatus and Australoheros facetum were used in the assays; fish were acclimated during 7 days in aereated fresh-water (FW), at constant temperature (20 ± 1ºC) and photoperiod (12D:12N). The experimental design contemplated three successive periods: Control (4 days in FW), Exposure (4 days in FW + 0.3 and 0.5 mg Cd L-1) and Recovery (7 days in FW); simultaneously the speed of individuals maintained in FW during 15 days (CoP) was determined. The swimming speed in both species increased in the Exposure period. After transfer to clean media (Recovery period), the altered values in A. facetum, exhibited a slight tendency to recovery (but without reaching the basal values registered in the Control period). In A. fasciatus a clear cut recovery response was registered in fish exposed to 0.3 mg. L-1 while in animals exposed to the highest concentration of Cd no recovery was registered. These differences were interpreted as evidences of dissimilar uptake and depuration rates of the toxic.Instituto de Limnología "Raúl A. Ringuelet

Cambios en la velocidad de nado como indicador del efecto tóxico del cadmio en Astyanax fasciatus y Australoheros facetum

Numerous studies have shown that the swimming performance parameters of fish may be useful indicators of their environmental stress. The swimming speed was evaluated in two Pampean species and its alteration as a result of their exposure to sublethal Cadmium concentrations. The swimming speed was calculated from a daily registry of the distance and the time of displacement of fish by means of special software. Juveniles specimens of Astyanax fasciatus and Australoheros facetum were used in the assays; fish were acclimated during 7 days in aereated fresh-water (FW), at constant temperature (20 ± 1ºC) and photoperiod (12D:12N). The experimental design contemplated three successive periods: Control (4 days in FW), Exposure (4 days in FW + 0.3 and 0.5 mg Cd L-1) and Recovery (7 days in FW); simultaneously the speed of individuals maintained in FW during 15 days (CoP) was determined. The swimming speed in both species increased in the Exposure period. After transfer to clean media (Recovery period), the altered values in A. facetum, exhibited a slight tendency to recovery (but without reaching the basal values registered in the Control period). In A. fasciatus a clear cut recovery response was registered in fish exposed to 0.3 mg. L-1 while in animals exposed to the highest concentration of Cd no recovery was registered. These differences were interpreted as evidences of dissimilar uptake and depuration rates of the toxic.Instituto de Limnología "Raúl A. Ringuelet

Cambios en la velocidad de nado como indicador del efecto tóxico del cadmio en Astyanax fasciatus y Australoheros facetum

Numerous studies have shown that the swimming performance parameters of fish may be useful indicators of their environmental stress. The swimming speed was evaluated in two Pampean species and its alteration as a result of their exposure to sublethal Cadmium concentrations. The swimming speed was calculated from a daily registry of the distance and the time of displacement of fish by means of special software. Juveniles specimens of Astyanax fasciatus and Australoheros facetum were used in the assays; fish were acclimated during 7 days in aereated fresh-water (FW), at constant temperature (20 ± 1ºC) and photoperiod (12D:12N). The experimental design contemplated three successive periods: Control (4 days in FW), Exposure (4 days in FW + 0.3 and 0.5 mg Cd L-1) and Recovery (7 days in FW); simultaneously the speed of individuals maintained in FW during 15 days (CoP) was determined. The swimming speed in both species increased in the Exposure period. After transfer to clean media (Recovery period), the altered values in A. facetum, exhibited a slight tendency to recovery (but without reaching the basal values registered in the Control period). In A. fasciatus a clear cut recovery response was registered in fish exposed to 0.3 mg. L-1 while in animals exposed to the highest concentration of Cd no recovery was registered. These differences were interpreted as evidences of dissimilar uptake and depuration rates of the toxic.Instituto de Limnología "Raúl A. Ringuelet

Examining Delay Intervals in the Diagnosis and Treatment of Primary Open Angle Glaucoma in an Egyptian Population and Its Impact on Lifestyle

Purpose. To examine causes as well as extent of delay in diagnosis and treatment of primary open angle glaucoma patients in a sample of Egyptians. Patients and Methods. 440 patients with primary open angle glaucoma were interviewed to evaluate delay in their diagnosis and treatment. The extent and cause of delay were investigated. The total delay interval, if any, was correlated with socioeconomic and other factors. Results. The median total delay was one year, with 50% of patients having a total delay of 1 year or less, of which 25% exhibited zero total delay. 25% of patients had a delay ranging from 1 to 3 years, and 25% had a total delay ranging from 3 to 27 years. Diagnostic delay accounted for 43.03% of cases. Longer delays were met in patients with certain socioeconomic factors. Patients with a positive family history of glaucoma displayed shorter delay periods. Conclusion. Significant delay in the diagnosis and treatment of glaucoma was found. Poor socioeconomic status seems to hinder timely diagnosis and treatment of POAG. Certain socioeconomic factors seem to correlate with the extent of delay. More effort is thus needed to subsidize the cost of investigations and treatment for glaucoma patients