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This article reports on an action research study that assessed the influence of cognitive and metacognitive strategies-based feedback in the oral performance of a group of 6th grade students at a public school in Medellin, Colombia. Researchers analyzed students' oral performance through assessment and self-assessment rubrics, applied inventories to students before and after giving them the strategies-based feedback, and interviewed all students and one parent. Results showed that strategies based feedback supported by previous strategies instruction can help students both increase the use of strategies and improve their oral performance.

Resumen: Introducción y objetivo: La epidemia de SARS-CoV-2 representa un riesgo especial para los pacientes en hemodiálisis (HD) por sus comorbilidades, y el cursar con una inflamación más severa con menos síntomas y peor evolución. Nuestro objetivo fue conocer las características clínicas y bioquímicas de los pacientes en hemodiálisis (HD) que presentaron cuadro sospechoso de COVID-19 (por sus siglas en inglés de Corona Virus Disease – 2019), sus factores de riesgo y desenlace. Material y métodos: Estudio de reporte de casos, retrospectivo, observacional, en los pacientes en HD sospechosos de COVID-19. Registrándose comorbilidades, clínica, laboratorio, prueba de transcripción reversa cuantitativa de la reacción en cadena de polimerasa (RT-qPCR) para SARS-COV-2 y desenlace. Se realizó estadística descriptiva y análisis de regresión lineal y logístico. Resultados: De 1.514 personas que recibían tratamiento de HD, 248 pacientes presentaron sintomatología sospechosa de COVID-19 (106 positivos, 83 negativos y 59 sospechosos por PCR), mediana de edad de 51 años (RI 36-63 años), 54,8% masculinos, hipertensión (87,5%), hemoglobina de 8,9 g (RI 7,5-10,6 g); la sintomatología de tos, fiebre y disnea (65,7, 64,5 y 53,2% respectivamente). El porcentaje de letalidad en el grupo de los pacientes con RT-qPCR positiva fue de 29,24%. Conclusiones: La tasa de mortalidad y letalidad es alta en este tipo de población. El grupo etario, el sexo y las comorbilidades cardiometabólicas se comportan similar al resto de la población no renal. El estado bioquímico preexistente no marca una diferencia en el desenlace. La sintomatología predominante es respiratoria. Abstract: Introduction and objective: The SARS-CoV-2 epidemic represents a special risk for patients on hemodialysis (HD) due to their comorbidities and the fact that they often have a more severe case of inflammation with fewer symptoms and a worse evolution and outcome. The aim of this study was to detect the clinical and biochemical characteristics of patients on hemodialysis (HD) who presented a suspicious involvement of COVID-19 (Corona Virus Disease – 2019), their risk factors and specific outcomes. Material and methods: This is a retrospective, observational case report study in HD patients suspected of having COVID-19. Records pointed to comorbidities, clinical and laboratory tests, quantitative reverse transcription polymerase chain reaction (RT-qPCR) tests for SARS-COV-2 and outcomes. Descriptive statistics and linear and logistic regression analyses were performed. Results: Of the total number of HD patients (1514), 248 HD patients were suspected to have COVID-19 (106 were positive, 83 were negative and 59 suspected using PCR testing); the median age was 51 years (IR 36-63 years), 54.8% were males, had hypertension (87.5%), with a hemoglobin count of 8.9 g (IR 7.5-10.6 g) and symptoms such as cough, fever and dyspnea (65.7, 64.5 and 53.2%, respectively). The fatality rate in the group of patients with positive RT-qPCR was 29.24%. Conclusions: The mortality and fatality rate is often high in this population. The age group, sex, and cardio-metabolic comorbidities behave similarly to the rest of the non-renal population. Pre-existing biochemical status does not make a difference in the outcome. The predominant symptomatology was pulmonary in nature.

Copyright of Revista U.D.C.A Actualidad & Divulgación Científica is the property of Universidad de Ciencias Aplicadas y Ambientales U.D.C.A and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The Wnt-β-catenin and PI3K-AKT-FOXO3a pathways have a central role in cancer. AKT phosporylates FOXO3a, relocating it from the cell nucleus to the cytoplasm, an effect that is reversed by PI3K and AKT inhibitors. Simultaneous hyperactivation of the Wnt-β-catenin pathway and inhibition of PI3K-AKT signaling promote nuclear accumulation of β-catenin and FOXO3a, respectively, promoting cell scattering and metastasis by regulating a defined set of target genes. Indeed, the anti-tumoral AKT inhibitor API-2 promotes nuclear FOXO3a accumulation and metastasis of cells with high nuclear β-catenin content. Nuclear β-catenin confers resistance to the FOXO3a-mediated apoptosis induced by PI3K and AKT inhibitors in patient-derived primary cultures and in corresponding xenograft tumors in mice. This resistance is reversed by XAV-939, an inhibitor of Wnt-β-catenin signaling. In the presence of high nuclear β-catenin content, activation of FOXO3a by PI3K or AKT inhibitors makes it behave as a metastasis inductor rather than a proapoptotic tumor suppressor. We show that it is possible to evaluate the β-catenin status of patients' carcinomas and the response of patient-derived cells to target-directed drugs that accumulate FOXO3a in the nucleus before deciding on a course of treatment. We propose that this evaluation could be essential to the provision of a safer and more effective personalized treatment., Colon cancer is a leading cause of death worldwide1. Although surgical resection combined with adjuvant therapy is efficient at the early stages of disease, subsequent relapse and metastasis often occur. [...]

Transient focal cerebral ischemia in the rat alters vessel properties, and spontaneously hypertensive rats (SHR) show a poorer outcome after ischemia. In the present study we examined the role of hypertension on vessel properties after ischemia-reperfusion. The right middle cerebral artery (MCA) was occluded (90 min) and reperfused (24 h) in SHR (n = 12) and Wistar-Kyoto rats (WKY; n = 11). Sham-operated rats (SHR, n = 10; WKY, n = 10) were used as controls. The structural, mechanical, and myogenic properties of the MCA were assessed by pressure myography. Nuclei distribution and elastin content and organization were analyzed by confocal microscopy. Infarct volume was larger in SHR than in WKY rats. Ischemia-reperfusion induced adventitial hypertrophy associated with an increase in the total number of adventitial cells. In addition, fenestrae area and arterial distensibility increased and myogenic tone decreased in the MCA of WKY rats after ischemiare-perfusion. Hypertension per se induced hypertrophic inward remodeling. Ischemia-reperfusion decreased the cross-sectional area of the MCA in SHR, without significant changes in distensibility, despite an increase in fenestrae area. In addition, MCA myogenic properties were not altered after ischemia-reperfusion in SHR. Our results indicate that in normotensive rats, MCA develops a compensatory mechanism (i.e., enhanced distensibility and decreased myogenic tone) that counteracts the effect of ischemia-reperfusion and ensures correct cerebral irrigation. These compensatory mechanisms are lost in hypertension, thereby explaining, at least in part, the greater infarct volume observed in SHR. cerebral blood flow; hypertension doi:10.1152/ajpheart.00165.2007

Background: Iron dyshomeostasis appears to be an early event in the Alzheimer's continuum. However, little is known how incipient cerebral iron deposition affects brain structure and function in cognitively unimpaired (CU) individuals. Here, we assessed the relationship between mean intensities in subcortical nuclei, a proxy measure for iron content, and regional cortical thickness as well as brain metabolism in middle‐aged CU individuals and sought for interactions with biomarkers of Alzheimer's pathology. Method: We included 288 CU adults from the ALFA+ cohort (Table 1). Mean intensities were quantified from T2‐weighted magnetic resonance images in 18 a priori defined subcortical nuclei. Due to the high correlations among regional intensities, we performed a principal component analysis to obtain a single measurement of cerebral iron load (Table 2). Cortical thickness (CT) of the "Alzheimer's disease (AD) signature" composite region of interest (ROI) was assessed using FreeSurfer v6.0. [18F]fluorodeoxyglucose (FDG) PET scans were used to calculate the standardized uptake value ratio (SUVr) within a meta ROI. We created separate general linear models where cortical thickness and PET meta‐ROIs were the dependent variables, while the first principal component (PC1), age, sex, APOE‐ε4 status, and education level were entered as predictors. In additional models, CSF levels of amyloid‐beta ratio (Aβ42/40) and phosphorylated tau (p‐tau) were entered as covariates. We also tested the interaction between PC1 and CSF Aβ42/40 and p‐Tau status. Statistical significance was set at p<0.05. Result: PC1 explained 47.64% of the variance of mean intensities in subcortical regions with lower values denoting higher iron concentration. Lower PC1 values were negatively associated with AD‐signature thickness (p=0.004), but not with brain glucose metabolism in the meta ROI (p=0.936). (Table 3. Figure 1). These results remained unchanged once AD core CSF biomarkers were entered into the model. No significant interactions with abnormal levels of CSF Aβ or p‐Tau were revealed with AD‐signature thickness or brain metabolism. Conclusion: In CU individuals, higher content of iron deposition is associated with reduced thickness, but not glucose metabolism, in cortical areas that typically show atrophy early in the Alzheimer's continuum. This association was not modified by the presence of altered biomarkers of AD pathology. [ABSTRACT FROM AUTHOR]

Hamstring muscle injuries are the most prevalent among athletes who engage in sprinting activities. Their most frequent location is where the long head of the biceps femoris joins with the semitendinosus muscle to form the conjoint hamstring tendon. Just distal to this area, an additional group of fibers of the semitendinosus originate from medial aspect of biceps femoris. The objective of this study was to analyze the morphological characteristics of this union and to discuss its potential role in hamstring tears. Anatomical dissection was performed on 35 thighs. Samples obtained from this region were sectioned and stained with Masson's trichrome for further histological evaluation. A group of fibers from the semitendinosus muscle originating from the long head of the biceps femoris were observed in all 35 specimens. This origin was located 67 ± 12 mm from the ischial tuberosity and was 32 ± 14 mm in length. This group of muscle fibers had a width of 10.9 ± 5.3 mm and a thickness in the anteroposterior axis of 3.2 ± 1.4 mm. Its pennation angle was 9.2 ± 1.5 degrees. Microscopic examination showed muscle cells from both muscles contacting interposed tendinous tissue. In conclusion, fibers of the semitendinosus muscle consistently arise from the proximal aspect of the long head of biceps femoris. The morphological characteristics of this junction have functional implications. The horizontal component of the semitendinosus vector could pull the long head of the biceps femoris medially during its shortening—lengthening cycle, rendering it an intrinsic risk factor for hamstring injuries. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of the current study is twofold. First, to investigate the variability of the petrotympanic fissure's (PTF) morphology in anatomized human cadaveric specimens using multi-detector computed tomography (MDCT), and second, to compare the resulting measurements to investigate the possibilities of applying MDCT in the determination of PTF morphology in living humans. Methods: Specimens (n = 15) containing the temporal bone and TMJ were obtained from embalmed adult female (53.3%) and male (46.7%) cadavers and imaged using a helical 16-row scanner. Afterwards, cryosections were obtained and morphometric parameters were measured. Degree of agreement between both determinations was investigated and morphometric variables were also compared between PTF types. Results: Three different types of PTF were identified. Type 1 was a wide tunnel-shaped structure. It was found in 20% of the cases. Type 2 was wide in the entrance but gradually narrows to the tympanic cavity. It was found in 46.7% of specimens. Finally, type 3, which was observed in 33.3% of the cases, was wide at the entrance of the mandibular fossa, followed by a middle region with flat-shaped tunnel structure and a narrow exit. The PTF's vertical diameters at the mandibular fossa, midpoint, and tympanic cavity and the width at the mandibular fossa all were significantly greater in type 1 specimens. Conclusions: MDCT is suitable for investigating the variable morphology of human PTF and its association with middle ear's and TMJ pathologies. [ABSTRACT FROM AUTHOR]

The development of increasingly sophisticated methods to acquire high-resolution images has led to the generation of large collections of biomedical imaging data, including images of tissues and organs. Many of the current machine learning methods that aim to extract biological knowledge from histopathological images require several data preprocessing stages, creating an overhead before the proper analysis. Here we present PyHIST (https://github.com/manuel-munoz-aguirre/PyHIST), an easy-to-use, open source whole slide histological image tissue segmentation and preprocessing command-line tool aimed at tile generation for machine learning applications. From a given input image, the PyHIST pipeline i) optionally rescales the image to a different resolution, ii) produces a mask for the input image which separates the background from the tissue, and iii) generates individual image tiles with tissue content. Author summary: Histopathology images are an essential tool to assess and quantify tissue composition and its relationship to disease. The digitization of slides and the decreasing costs of computation and data storage have fueled the development of new computational methods, especially in the field of machine learning. These methods seek to make use of the histopathological patterns encoded in these slides with the aim of aiding clinicians in healthcare decision-making, as well as researchers in tissue biology. However, in order to prepare digital slides for usage in machine learning applications, researchers usually need to develop custom scripts from scratch in order to reshape the image data in a way that is suitable to train a model, slowing down the development process. With PyHIST, we provide a toolbox for researchers that work in the intersection of machine learning, biology and histology to effortlessly preprocess whole slide images into image tiles in a standardized manner for usage in external applications. [ABSTRACT FROM AUTHOR]

Copyright of Revista Medica del IMSS is the property of Direccion de Prestaciones Medicas - IMSS and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: Excessive blood loss is a relevant complication of partial liver resection. Topical hemostatic agents have proven useful to improve the control of the bleeding in this among other surgical indications. Until now all of these products have been based on the action of thrombin. In contrast TT-173 is a new topical hemostatic agent based on recombinant tissue factor naturally incorporated into membrane vesicles. This work sought to assess the efficacy and toxicity of TT-173 in an animal model of liver resection. Materials and Methods: Procoagulant activity of 0.15, 0.41, and 1 mg of TT-173 was evaluated in pigs subjected the resection of hepatic lobe margins. The most effective of these doses was also compared against thrombin. In addition, the toxicity, local tolerance, systemic absorption, and immunogenicity of the product were investigated in rats subjected to liver biopsy lesion. Results: The three doses of TT-173 evaluated significantly reduced the bleeding time in liver lesions. The highest dose of product was significantly more effective than the others and thrombin. Application of high doses of TT-173 in rats did not cause any local or systemic alterations. Absorption into blood stream was negligible and no immunogenic reaction against the product was detected. Conclusions: TT-173 shows favorable pharmacodynamic properties for improving hemostasis in partial liver resection which support further investigation of the product in this surgical indication. [ABSTRACT FROM AUTHOR]

External appearance is the main aesthetic outcome in patients who undergo surgical procedures. Scars located in exposed areas, such as the neck and face, are important for patients. There are at least eight instruments that are used to evaluate postoperative scars, but few fulfil standard methodological conditions. The Patient Scar Assessment Questionnaire (PSAQ) was designed and validated using psychometric methodology. However, this scale has not been translated or validated in the Spanish language. The aim of this study was to undergo a cross‐cultural adaptation and psychometric validation of the PSAQ scale to the Spanish language in patients who underwent head and neck surgery. We followed The Professional Society for Health Economics and Outcomes Research (ISPOR) guidelines for the translation and validation of health‐related scales. Forward and back translations were made by independent translators. We included adult patients who underwent thyroidectomy, parathyroidectomy, parotidectomy, and neck dissection. For the psychometric validation, we used a principal axis exploratory factor analysis with oblimin rotation. A reliability test involving Cronbachs alpha and the item‐total correlation was performed and for the convergent/concurrent validity, we selected the Spanish version of the Vancouver Scar Scale. A total of 180 patients were recruited. Factor analysis showed a five‐factor solution. Cronbachs alpha for the subscales was >0.7. The comparison between the PSAQ appearance subscale and the VSS demonstrated a high correlation (rho = − 0.89). In a sample of 62 patients, the test‐retest evaluation showed high correlation (0.74‐0.99). Our study supports the Spanish version of the PSAQ as a valid, reliable, and reproducible tool to assess the perception and impact of neck scars in Spanish‐speaking patients who undergo head and neck surgery. [ABSTRACT FROM AUTHOR]