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BACKGROUND: The Aspergillus Galactomannan Ag Virclia® (GMVClia) test is a monotest and automated galactomannan technique based on chemiluminescent immunoassay (CLIA). AIM: To evaluate the performance of the GM-VClia test in serum and bronchioalveolar lavage (BAL) samples previously processed with the Platelia ™ Aspergillus EIA kit (GM-Plat). METHODS: 56 samples of serum 40 from BAL (some of them with galactomaman determination in both samples), from patients with pulmonary diseases, hematological diseases, SLE, Covid-19 and tumors, among others, were studied. Thirteen patients had invasive aspergillosis (1 proven and 12 probable). RESULTS: The correlation between both methods for serum and BAL was r = 0.8861 p < 0.0001 and r = 0.6368 p < 0.001, respectively. There was a global concordance of 67.7% (65/96), being 85.7% (48/56) in sera and 42.5.0% (14/49) in BAL. By raising the cut-off point in LBA by GM-VClia, the agreement increased to 85.7%. CONCLUSION: A greater correlation and concordance was observed in sera than in BAL. The GM-VClia kit had a higher sensitivity and NPV than the GM-Plat kit. The disadvantages of GM-VClia are the "doubtful" category, which makes interpretation difficult and that with the current cut-off points in LBA the correlation with GM-Plat is lower. The advantages are its greater sensitivity, ease of processing and faster results.

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INTRODUCCIÓN: La prueba Aspergillus galactomannan Ag Virclia® (GM-VClia) es una técnica de galactomanano monotest, auto-matizada, basada en inmunoensayo quimioluminiscente (CLIA). OBJETIVO: Evaluar el desempeño del test de GM-VClia en muestras de suero y lavado bronquioalveolar (LBA) procesadas previamente con el kit Platelia™ Aspergillus EIA (GM-Plat). MATERIALES Y MÉTODOS: Se estudiaron 56 muestras de suero y 40 de LBA, correspondientes a un total de 59 pacientes (algunos con determinación de galactomamano en ambas muestras) con enfermedades pulmonares, hematológicas, LES, Covid-19 y tumores, entre otros. Trece pacientes tuvieron aspergilosis invasora (1 probada y 12 probables). RESULTADOS: La correlación entre ambos métodos para suero y LBA fue r = 0,8861 p < 0,0001 y r = 0,6368 p < 0,001, respectivamente. Hubo una concordancia global de 67,7% (65/96), siendo de 85,7% (48/56) en sueros y 42,5,0% (14/49) en LBA. Al subir el punto de corte en LBA por GM-VClia la concordancia aumentó a 85,7%. CONCLUSIONES: Se observó una mayor correlación y concordancia en sueros que en LBA. El kit GM-VClia presentó una mayor sensibilidad y valor predictor negativo (VPN), que el kit GM-Plat. Las desventajas de GM-VClia, la constituyen la categoría "dudoso", que dificulta la interpretación y que, con los puntos de corte actuales en LBA, la correlación con GM-Plat es menor. Las ventajas son su mayor sensibilidad, facilidad de procesamiento y una mayor rapidez en los resultados.

BACKGROUND: The Aspergillus Galactomannan Ag Virclia® (GMVClia) test is a monotest and automated galactomannan technique based on chemiluminescent immunoassay (CLIA). AIM: To evaluate the performance of the GM-VClia test in serum and bronchioalveolar lavage (BAL) samples previously processed with the Platelia ™ Aspergillus EIA kit (GM-Plat). METHODS: 56 samples of serum 40 from BAL (some of them with galactomaman determination in both samples), from patients with pulmonary diseases, hematological diseases, SLE, Covid-19 and tumors, among others, were studied. Thirteen patients had invasive aspergillosis (1 proven and 12 probable). RESULTS: The correlation between both methods for serum and BAL was r = 0.8861 p < 0.0001 and r = 0.6368 p < 0.001, respectively. There was a global concordance of 67.7% (65/96), being 85.7% (48/56) in sera and 42.5.0% (14/49) in BAL. By raising the cut-off point in LBA by GM-VClia, the agreement increased to 85.7%. CONCLUSION: A greater correlation and concordance was observed in sera than in BAL. The GM-VClia kit had a higher sensitivity and NPV than the GM-Plat kit. The disadvantages of GM-VClia are the "doubtful" category, which makes interpretation difficult and that with the current cut-off points in LBA the correlation with GM-Plat is lower. The advantages are its greater sensitivity, ease of processing and faster results.

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PURPOSE: To evaluate the learning curve of the simplified fluoroscopic biplanar (0-90º) puncture technique for percutaneous nephrolithotomy. METHODS: We prospectively evaluated patients with renal stones treated with percutaneous nephrolithotomy by a single institution's fellows employing the simplified bi-planar (0-90º) fluoroscopic puncture technique for renal access. The learning curve was assessed with the fluoroscopic screening time and the percutaneous renal puncture time. Data obtained were compared to a subset of patients operated by a senior surgeon. RESULTS: Eighty-nine patients were included in the study. Forty patients were operated by fellow-1, 39 by fellow-2, and 10 patients by the senior surgeon. Demographic data of all patients between groups were homogeneous, with no difference in gender (p = 0.432), age (p = 0.92), stone volume (p = 0.78), puncture laterality (p = 0.755), and body mass index (p = 0.365). The mean puncture time was 7.5, 4, and 3.1 min for fellow-1, fellow-2, and expert, respectively. The mean fluoroscopic screening time for the puncture was 10, 11, and 5.1 s for fellow-1, fellow-2, and the expert, respectively. Stone cases, both fellows needed to complete 10 procedures to match the senior surgeon in the mean puncture time (p = 0.046); meanwhile, the fluoroscopic screening time was equal even before to complete 10 procedures. CONCLUSION: This study suggests that with the simplified biplanar (0-90º) puncture technique, the fluoroscopic screening time used in the learning process is brief. A novice fellow could require to complete ten cases to flatten the learning curve treating complex stone cases, and a flat learning curve is seen since the beginning when treating simple renal stones.

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Spider community inventories have relatively well-established standardized collecting protocols. Such protocols set rules for the orderly acquisition of samples to estimate community parameters and to establish comparisons between areas. These methods have been tested worldwide, providing useful data for inventory planning and optimal sampling allocation efforts. The taxonomic counterpart of biodiversity inventories has received considerably less attention. Species lists and their relative abundances are the only link between the community parameters resulting from a biotic inventory and the biology of the species that live there. However, this connection is lost or speculative at best for species only partially identified (e. g., to genus but not to species). This link is particularly important for diverse tropical regions were many taxa are undescribed or little known such as spiders. One approach to this problem has been the development of biodiversity inventory websites that document the morphology of the species with digital images organized as standard views. Their main contributions are the dissemination of phenotypic data for species difficult to identify or new with the assignment of species codes, allowing species comparisons between areas regardless of their taxonomic status. The present paper describes a protocol to produce these websites almost automatically. This protocol was successfully applied to 237 species from a tropical primary forest in Mexico. The time and infrastructure required for the documentation of these species are discussed. Taxonomic information in terms of identification challenges, possible new species, and potential nomenclatural issues is described. In addition, the conventional community parameters (e. g., inventory completeness, species richness estimations, sampling intensity) are also calculated and compared through time and between methods. An optimized version for sampling allocation effort per season is presented and compared with protocols optimized for other tropical forests.

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Resumen Antecedentes: el proceso rehabilitador orientado a la recuperación motora posterior a un Ataque Cerebro Vascular (ACV), es un proceso complejo asociado con la aparición de signos positivos y negativos posterior a un daño de moto neurona superior (MNS). Objetivo: describir cuales son las efectos de la espasticidad en el proceso rehabilitador posterior a un ACV. Material y método: se realizó una revisión narrativa, a través de un plan de búsqueda por parte de tres revisores, explorando la base de datos PubMed, donde se utilizaron los términos MesH: Spasticity AND Motor Recovery AND Stroke, los límites de búsqueda fueron revisiones y ensayos clínicos en humanos y animales, publicados en los últimos 10 años con textos completos en inglés y español. Resultado: 71 artículos que cumplían con los criterios de búsqueda, fueron identificados, se seleccionaron 21 (16 ensayos clínicos y 5 revisiones), los que fueron analizados a través de las guías Caspe y se utilizaron para la confección de esta revisión. Conclusión: si bien existe amplia evidencia científica, esta no es concluyente, planteando que la espasticidad es fuente de compromiso funcional y discapacidad, pero no siempre es perjudicial, ya sus efectos pueden ser beneficiosos y en ocasiones no necesita tratamiento.

Background and Aim: The rehabilitation process oriented to motor recovery after a stroke is a complex process associated with the appearance of positive and negative signs after motor neuron damage. The aim was to describe the effects of spasticity in the rehabilitation process after a stroke. Methods: Three reviewers, exploring the PubMed database, carried out, a narrative review through a search plan, the terms MesH: Spasticity AND Motor Recovery AND Stroke were used; the search limits were reviews and clinical trials in humans and animals, published in the last 10 years with full texts in English and Spanish. Results: Seventy-one articles that met the search criteria were identified, 21 were selected (16 clinical trials and 5 reviews), which were analyzed through the CASPE guide and used for the preparation of this review. Conclusion: Although there is broad scientific evidence, this is not conclusive, stating that spasticity is a source of functional commitment and disability, but it is not always harmful, and its effects can be beneficial and sometimes do not need treatment.

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Seven new species of the genus Chrysometa Simon are described: C. citlaltepetl n. sp., C. triangulosa n. sp., C. rosarium n. sp., C. atotonilco n. sp., C. xamaticpac n. sp. C. puya n. sp. and C. sagicuta n. sp. Species identities were evaluated and sexes for each species matched with a fragment of the cytochrome c oxidase subunit I. These data were analyzed with maximum likelihood and the resulting cladograms separated all species with high support values (95-100) and an average distance of 0.093 %. The genetic signal also agreed with the diagnostic morphological features used to separate these taxa. The sex matching results discovered that the female of C. chipinque Levi actually belongs to C. puya n. sp.; the correct female of C. chipinque is here described for the first time. A redescription of the male of C. chipinque and the female of C. puya is also provided. All species were collected as part of a faunistic inventory from two oak forests near Pico de Orizaba Volcano National Park. A total of 399 adult specimens, 209 females and 195 males, were sorted and identified. Most individuals were collected from medium height vegetation by beating trays and from high vegetation by direct collecting at night. High resolution images for all species are available at www.unamfcaracnolab.com. Finally, the functional anatomy of the epigynum for the species described here is discussed.

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Little is known about the diversity of parasites of the deep-sea fish of the world's oceans. Here, a new species of monogenean parasite of the deep-sea skate Gurgesiella furvescens is described. Specimens of parasites were obtained from the skin of two specimens of the dusky finless skate, G. furvescens (Rajidae), in the vicinity of Valparaiso (33°S, 72°W), central Chile, from midwater trawl fishing at depths of 350-450 m. Both morphological and molecular analyses were conducted to provide a full description of the new species, named Acanthocotyle gurgesiella. For the molecular analyses, nuclear large subunit (LSU) rDNA and the mitochondrial gene cytochrome c oxidase 1 (COI) were used. From the morphological analysis and a comparison with the known species of the genus, A. gurgesiella can be identified by a combination of morphological characteristics, including the number of testes, number of radial rows of sclerites in the pseudohaptor, aperture of the genital pore and shape of the vitelline follicles. The results from the DNA analysis indicated that A. gurgesiella has a genetic divergence of 3.2-3.7% (LSU rDNA gene) from A. urolophi, the only congener species for which molecular data are available.

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The genetic population structure and genetic diversity of yellowtail kingfish Seriola lalandi from the coastal south-eastern Pacific Ocean (SEP) were evaluated at spatiotemporal scale in order to understand the ecology of this species. Between 2012 and 2015, temporal and spatial population genetic structure and a low genetic diversity were detected in S. lalandi from SEP. These results suggest that S. lalandi specimens arriving annually from offshore to the SEP coast could come from at least two genetically distinct populations, revealing a particular life strategy (i.e. reproductive or habitat segregation) for this fish species. Therefore, the SEP coast might constitute a point of population mixing for this species. Additionally, the low genetic diversity of S. lalandi in the SEP could be a result of a founder effect or overfishing. Regardless of the process explaining the genetic diversity and structure of S. lalandi in this geographical area, this new information should be considered in order to implement successful fishery management of this resource in the South Pacific.

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Introducción: La Suprarrenalectomía quirúrgica es el tratamiento de elección en lesiones tumorales de la glándula suprarrenal mayores de 4 cm o aquellos que resulten funcionales. La técnica laparoscópica esta asociada a menor sangrado, morbilidad perioperatoria y estadía hospitalaria. El apoyo del abordaje single-port (LESS) se asocia además a menor dolor y mejores resultados estéticos, pero conlleva a una mayor complejidad técnica, sin embargo esta dificultad puede ser eliminada con el apoyo robótico, conservando los beneficios de la técnica single port.(AU)

Introduction: Surgical adrenalectomy is the treatment of choice in tumors of the adrenal gland larger than 4 cm or those that are functional. The laparoscopic technique is associated with less bleeding, perioperative morbidity and hospital stay. The support of the single-port approach (LESS) is also associated with less pain and better aesthetic results, but it leads to greater technical complexity, however this difficulty can be eliminated with robotic support, while retaining the benefits of the single port technique.

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INTRODUCCIÓN: La fractura de cadera (FC) es la causa más frecuente de hospitalización en servicios de urgencia ortopédicos. La mayoría ocurre en pacientes ancianos con mala calidad ósea y trauma menor. La pérdida de los reflejos protectores y reducción de la fortaleza ósea son factores de riesgo. OBJETIVO: Caracterizar epidemiológicamente los egresos quirúrgicos por FC en Hospital de Victoria 2009-2013, respecto a antecedentes nacionales, no existen registros previos, así generar información cuantitativa para decisiones administrativas. MATERIALES Y MÉTODO: Estudio cuantitativo, descriptivo y retrospectivo de corte transversal, realizado en Hospital de Victoria, Chile, durante enero-febrero 2014. Se utiliza la tabla digitalizada de Diagnósticos de Egresos Quirúrgicos entre 2009-2013. Para los criterios de inclusión, se usa la Clasificación Internacional de EnfermedadesCIE-10, seleccionando Coxartrosis, Fractura del cuello femoral, pertrocanteriana, subtrocanteriana;de los cuales los intervenidos quirúrgicamente, excluyendo los no quirúrgicos. El análisis se realizacon Microsoft Office Excel© 2007 y EPIDAT© 3,1. El estudio es aprobado por el Comité de Ética de la Universidad Mayor, Temuco, Chile. RESULTADOS: Se obtiene N= 204 con promedio de 75años, la mayoría mujeres. Del total, el 75 por ciento son fracturas del cuello femoral, y en la mayoría se usa osteosíntesis. Por otro lado, el 22 por ciento se diagnostica de coxartrosis, y todas reciben endoprótesis. DISCUSIÓN: Existe un incremento del grupo de adultos mayores como de incidencia de FC. La incidencia total a nivel países de riesgo bajo, y a nivel provinciales moderado. Determina que la patología es de mayor riesgo en Malleco respecto al nacional

INTRODUCTION: Hip fracture (HF) is the most frequent cause of hospitalization in emergency orthopedic services. They usually occur in elderly patients with poor bone quality and lower trauma. The loss of protective and reduced bone strength reflexes are risk factors. OBJECTIVE: To characterize the epidemiological profile of surgical discharges with diagnosis of HF, Hospital of Victoria, 2009-2013, regarding national background, of which there are no previous records, thus generate quantitative information for making management decisions. MATERIALS AND METHODS: a quantitative, descriptive and retrospective cross-sectional study, carried out in Hospital of Victoria, Chile, during January February 2014. It is used the digitalized Table of Diagnostics of Surgical Expenses of 2009-2013. The International Classification of Diseases ICD-10 is used for the inclusion criteria, and are selected: Coxarthrosis, Fracture of the femoral neck, pertrochanteric, and subtrochanteric; of which only surgically. Excluding non-surgical. The analysis is performed with Microsoft Office Excel 2007 and EPIDAT © © 3.1. The study is approved by the Ethics Committee of the Universidad Mayor, Temuco, Chile. RESULTS: N= 204 is obtained, mostly women, mean 75.5 years. Of the total, 75.5 percent are femoral neck fractures, of which67.5 percent is used osteosynthesis. Furthermore, 22.1 percent were diagnosed with coxarthrosis, and all of them receiving endoprosthesis. DISCUSSION: There is a constant increase in the elderly group and incidence of HF. The national overall incidence was set as low risk, but atlocal level, it is moderate. It determines that the condition is riskier in the Province of Malleco rather than the national level

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INTRODUCTION: Extracorporeal Shock Wave Lithotripsy (ESWL) is currently the recommended treatment for intra-renal calculi smaller than 2 cm. However the low Stone Free Rate (SFR) in lower pole calculi gives rise to new techniques, such us retrograde intrarenal surgery (RIRS), for improve the surgery outcomes. OBJECTIVE: To compare the efficacy of a treatment with ESWL with RIRS, in terms of SFR after surgery, in patients with kidney stones up to 15 mm in the lower pole. MATERIAL AND METHODS: A prospective study was carried out in order to assess the results of ESWL and RIRS in patients with lower pole stones less than 15 mm. Among a total of 55 patients, 31 were underwent to ESWL (Group 1) and the remaining 24 to RIRS (Group 2). Clinical data recorded, including general characteristics of each patient, were: calculi size, side, operative time, complications according to Clavien scale, SFR and the presence of residual fragments at 2 months post-treatment assessed by a CT scan. STATA 11 was used to perform the statistical analysis. RESULTS: There were no differences for general descriptors among groups with the exception of a significantly longer operative time for RIRS. The rates of SFR and residual fragments lesser than 3 mm. were lower in the RIRS group than in ESWL ones. RIRS also showed a lower rate of clinically significant fragments (0% vs 42.3%. P < .05). In the subgroup of patients with stones between 10/15 mm RIRS showed higher SFR (75% vs. 41.2%) and a lower rate of stones>3 mm (0% vs. 58.8%), being statistically significant (P < .05). Clavien III or higher complications were not reported in any of the groups. CONCLUSIONS: In the treatment of lower pole stone RIRS has the same results than ESWL in terms of SFR. Regarding absence of a clinically significant residual fragment, RIRS was superior to ESWL. A bigger sample size is required in order to confirm this results.

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Two new species, Encotyllabe cheilodactyli and Encotyllabe antofagastensis (Monogenea: Capsalidae), have been found in the pharyngeal plates of Cheilodactylus variegatus and Anisotremus scapularis, respectively, in northern Chile (23°38'N, 70°24'W). Descriptions of the new species were based on morphometric and molecular evidence. Both species differ from previously described species of the genus by a combination of characteristics, including the size and relative position of the testes and the shapes of the major and small hamulus. In addition, E. cheilodactyli is unique among the known species of Encotyllabe due to the testes crossing the equatorial line of the body proper, and E. antofagastensis is unique among the known species of Encotyllabe due to its penis structure and anatomy leading to the genital pore. The analysis of the cytochrome c oxidase I gene as well as morphometric analyses demonstrated that the specimens belonged to 2 different species.

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The electrochemical oxidation (EO) treatment in water of three conazole fungicides, myclobutanil, triadimefon and propiconazole, has been carried out at constant current using a BDD/SS system. First, solutions of each fungicide were electrolyzed to assess the effect of the experimental parameters such as current, pH and fungicide concentration on the decay of each compound and total organic carbon abatement. Then a careful analysis of the degradation by-products was made by high performance liquid chromatography, ion chromatography and gas chromatography coupled with mass spectrometry in order to provide a detailed discussion on the original reaction pathways. Thus, during the degradation of conazole fungicides by the electrochemical oxidation process, aromatic intermediates, aliphatic carboxylic acids and Cl(-) were detected prior to their complete mineralization to CO2 while NO3(-) anions remained in the treated solution. This is an essential preliminary step towards the applicability of the EO processes for the treatment of wastewater containing conazole fungicides.

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La nefrolitectomía percutánea (NLP) es una técnica establecida para el tratamiento de nefrolitiasis de gran tamaño que finaliza dejando una nefrostomía para hemostasia, drenaje y facilitar una eventual revisión. Nuestro grupo publicó recientemente un estudio prospectivo y randomizado que demostró la factibilidad y seguridad de realizar NLP “tubeless” (sin nefrostomía y con catéter pigtail) en un grupo seleccionado de pacientes (sin litiasis residual ni sangrado intra operatorio significativo, con acceso percutáneo único y tiempo operatorio menor a 2 horas).Objetivo: Comparar el uso de catéter ureteral tipo pigtail versus catéter ureteral externalizado por 24 horas en pacientes sometidos a NLP “tubeless”. Métodos: Sesenta y ocho pacientes sometidos a NLP ¨tubeless” fueron prospectivamente randomizados para el uso de catéter pigtail (Grupo 1) o catéter ureteral externalizado por una noche (Grupo 2). Se evaluó el dolor pos operatorio, estadía hospitalaria, caída del hematocrito y desarrollo de hematomas perirrenales objetivados por tomografía axial computarizada no contrastada. Para el análisis estadístico un p value <0,05 fue considerado significativo. Resultados: Los grupos fueron comparables en edad, distribución de sexo, índice de masa corporal y carga litiásica. No difirieron en dolor pos operatorio ni incidencia de hematomas. El Grupo 1 tuvo una estadía hospitalaria y una caída del hematocrito significativamente mayor. Conclusión: Los resultados sugieren que ambas conductas son factibles y seguras. La mayor estadía hospitalaria del Grupo 1 y la posterior necesidad de cistoscopia para retirar el catéter pigtail favorecen el uso de catéteres ureterales externalizados. Además se validan los criterios utilizados para la aplicación de la técnica tubeless en NLP...

Percutaneous nephrolithotomy (PNL) is an established technique for the management of big renal calculi that finishes leaving a nephrostomy tube to provide hemostasia, drainage and access for a second look when needed. We have recently published a prospective and randomized study demonstrating the feasibility and safety of performing “tubeless” PNL (without nephrostomy and leaving a pigtail catheter) in a selected group of patients (no significant residual lithiasis nor significant intraoperative bleeding, single access and less of 2 hours of surgery).Objective: Compare the use of pigtail catheter versus night-externalized ureteral catheter in patients subjected to “tubeless” PNL. Methods: Sixty eight patients undergoing “tubeless” PNL were prospectively randomized for the use of pigtail catheter (Group 1) or 24 hours-externalized ureteral catheter (Group 2).Postoperative pain, hospital stay length, hematocrit drop and evidence of peri-renal hematomas in non-enhanced computarized tomography were evaluated. For statistical analysis a p value <0.05 was considered significant. Results: Groups were similar in age, sex distribution, body mass index and stone burden. No differences in postoperative pain or incidence of hematomas were observed. Group 1 had a longer hospital stay and a greater hematocrit drop. Conclusion: These results suggest that both alternatives are feasible and safe. The longer hospital stay in Group 1 and the further need of cystoscopy to remove the pigtail catheter favors the use of 24 hours-externalized ureteral catheter. In addition, we validate our intraoperative criteria for performing “tubeless” PNL...

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INTRODUCTION: Female urethral stenosis is not a very common pathology and its treatment is controversial. Therapeutic options vary from urethral dilatation and internal urethrotomy to other more complex reconstructive surgical techniques. The use of oral mucosa grafts to treat urethral stenosis has provided excellent long-term results in men, however there are few studies on their use in female urethral stenosis. We present our experience in the management of urethral stenosis using dorsal oral mucosa grafting. MATERIALS AND METHODS: We present 2 cases of female patients with a history of repeated urinary tract infections associated with low obstructive uropathy. In both cases, we encountered distal urethral stenosis, where both were treated with urethral plasty by means of dorsal oral mucosa grafting. RESULTS: The surgery took place without complications. Hospitalization time was 24 hours in both cases. The catheter was removed on the tenth postoperative day. The urethrocystography showed good urethral calibre with no signs of urinary fistula. After a mean follow-up of 18 months, neither patient presented symptoms of low obstructive uropathy or urinary incontinence. CONCLUSIONS: Urethroplasty with dorsal oral mucosa grafting is a reproducible and effective therapeutic option for the treatment of urethral stenosis in women.

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Soluble oligomers of the amyloid-ß peptide (AßOs) accumulate in Alzheimer's disease (AD) brain and have been implicated in mechanisms of pathogenesis. The neurotoxicity of AßOs appears to be, at least in part, due to dysregulation of glutamate signaling. Here, we show that AßOs promote extracellular accumulation of glutamate and d-serine, a co-agonist at glutamate receptors of the N-methyl-d-aspartate subtype (NMDARs), in hippocampal neuronal cultures. The increase in extracellular glutamate levels induced by AßOs was blocked by the sodium channel blocker tetrodotoxin (TTX), by the NMDAR blocker (+)-5-methyl-10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5,10-imine maleate (MK-801) and by removal of Ca(2+) from the extracellular medium, indicating dependence on excitatory neuronal activity. AßOs enhanced both the release of pre-synaptic vesicles labeled by FM1-43 and spontaneous post-synaptic activity measured by whole-cell patch-clamp. Activation of inhibitory GABA(A) receptors by taurine blocked the increase in extracellular glutamate levels, suggesting that selective pharmacological inhibition of neuronal activity can counteract the impact of AbOs on glutamate dyshomeostasis. Results reveal a novel mechanism by which Ab oligomers promote abnormal release of glutamate in hippocampal neurons, which may contribute to dysregulation of excitatory signaling in the brain.

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Currents mediated by calcium-activated chloride channels (CaCCs), observed for the first time in Xenopus oocytes, have been recorded in many cells and tissues ranging from different types of neurons to epithelial and muscle cells. CaCCs play a role in the regulation of excitability in neurons including sensory receptors. In addition, they are crucial mediators of chloride movements in epithelial cells where their activity regulates electrolyte and fluid transport. The roles of CaCCs, particularly in epithelia, are briefly reviewed with emphasis on their function in secretory epithelia. The recent identification by three independent groups, using different strategies, of TMEM16A as the molecular counterpart of the CaCC is discussed. TMEM16A is part of a family that has 10 other members in mice. The discovery of the potential TMEM16 anion channel activity opens the way for the molecular investigation of the role of these anion channels in specific cells and in organ physiology and pathophysiology. The identification of TMEM16A protein as a CaCC chloride channel molecule represents a great triumph of scientific perseverance and ingenuity. The varied approaches used by the three independent research groups also augur well for the solidity of the discovery.

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Currents mediated by calcium-activated chloride channels (CaCCs), observed for the first time in Xenopus oocytes, have been recorded in many cells and tissues ranging from different types of neurons to epithelial and muscle cells. CaCCs play a role in the regulation of excitability in neurons including sensory receptors. In addition, they are crucial mediators of chloride movements in epithelial cells where their activity regulates electrolyte and fluid transport. The roles of CaCCs, particularly in epithelia, are briefly reviewed with emphasis on their function in secretory epithelia. The recent identification by three independent groups, using different strategies, of TMEM16A as the molecular counterpart of the CaCC is discussed. TMEM16A is part of a family that has 10 other members in mice. The discovery of the potential TMEM16 anion channel activity opens the way for the molecular investigation of the role of these anion channels in specific cells and in organ physiology and pathophysiology. The identification of TMEM16A protein as a CaCC chloride channel molecule represents a great triumph of scientific perseverance and ingenuity. The varied approaches used by the three independent research groups also augur well for the solidity of the discovery.

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