Adeno-Associated Virus 8-Mediated Gene Therapy for Choroideremia: Preclinical Studies in in Vitro ind in Vivo Models

Choroideremia (CHM) is a slowly progressive X-linked retinal degeneration that results ultimately in total blindness due to loss of photoreceptors, retinal pigment epithelium, and choroid. CHM, the gene implicated in choroideremia, encodes Rab escort protein-1 (REP-1), which is involved in the post-translational activation via prenylation of Rab proteins. We evaluated AAV8.CBA.hCHM, a human CHM encoding recombinant adeno-associated virus serotype 8 (rAAV8) vector, which targets retinal cells efficiently, for therapeutic effect and safety in vitro and in vivo in a murine model of CHM. In vitro studies assayed the ability of the vector to produce functional REP-1 protein in established cell lines and in CHM patient derived primary fibroblasts. Assays included Western blots, immunofluorescent labeling, and a REP-1 functional assay which measured the ability of exogenous REP-1 to prenylate Rab proteins. The in vivo work used unilateral subretinal delivery of AAV8.hCHM to treat a murine model of CHM, with the effects of treatment evaluated with pupillometry, ophthalmoscopy, histology, and immunofluorescence analysis. The contralateral eye was treated with an AAV8.EGFP control. The results of the in vitro analysis demonstrated that the AAV8.CBA.hCHM vector was capable of inducing robust expression of REP-1 protein in a dose-responsive fashion in cultured cells, with the prenylation assay indicating that the exogenous REP-1 protein produced was capable of assisting in the activation of Rab proteins. This functional assay was also applied to CHM patient fibroblasts transduced with an AAV serotype 2 version of the vector and demonstrated that exogenous REP-1 produced in these cells was functional. The in vivo subretinal treatment of CHM mice with AAV8.CBA.hCHM resulted in the improvement of pupillary response in the treated eyes of some animals, as well as slowing of progression as judged by ophthalmoscopy. Histology of treated animals showed properly localized expression of human REP-1 and a significant improvement in outer retina health as determined by an increase in the thickness of the outer nuclear layer in treated eyes compared to controls. Combined, these results indicate that transduction with AAV8.CBA.hCHM reduces the biochemical and pathogenic defects in CHM both in vitro and in vivo and supports the application of AAV8 vectors in CHM gene therapy

Written corrective feedback: preferences and justifications of teachers and students in a Thai context

This study investigates the preferences and justifications of teachers and students on written corrective feedback (WCF) at a tertiary institution in Thailand and is aimed at expanding on prior similar studies conducted with smaller data sets in different contexts. Quantitative and qualitative questionnaire data were collected from 262 intermediate students and 21 teachers in order to test two hypotheses: (1) teachers’ and students’ WCF preferences would differ significantly, and (2) their justifications for their preferences would differ significantly. The hypotheses were confirmed: teachers rated indirect feedback with metalinguistic comment as being most useful while students most preferred direct feedback with metalinguistic comment. This trend extended to all types of direct feedback being preferred by students while teachers preferred all types of indirect feedback. The most common explanation for the teachers’ preferences was the development of metacognitive skills, while accuracy was the greatest concern for students. The pedagogical implications of the results regarding expectations, student agency, and self-efficacy are discussed

An Analysis on English Comprehension

Books and Buddies is a program run by Spread the Word Nevada (StWN) designed to help students who struggle with reading. As part of the program, students are given pre and post tests which measure comprehension, accuracy, and words correct per minute (WCPM). A data set was provided that included students\u27 scores on the pre and post test, as well as some general demographic information. A Python program was created to perform linear regressions on subsets of the data, measured on the three attributes listed above. The data was also divided into various categories for the sake of the regressions. This includes improvements based on the number of sessions attended and improvement per grade level. Alongisde the linear regressions, a paired sample mean t-test was performed to test for the significance of the student improvement