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The EMI Classroom Assessment Practices questionnaire was developed and administered to 40 EMI (English as a Medium of Instruction) university teachers in Taiwan with the aim of meeting EMI teachers' needs to conduct learning-oriented classroom assessment. The questionnaire surveyed the teachers in terms of their assessment practices in EMI and their self-perceived skills in these practices. The effects of the medium of instruction (English vs. Chinese) and teacher- and course-related variables related to assessment practices were also examined. The results revealed a high correlation between techniques that were less commonly practiced and those in which the teachers felt less skilled, signaling the possibility that assessment practices in the EMI classroom were dominated by the teachers' familiarity with techniques rather than by instructional objectives. In addition, the teachers perceived themselves to be less skilled in certain learning-oriented assessment practices, such as self-assessment and designing test items that assess higher-level cognitive abilities. Compared with courses taught in Chinese, EMI courses showed a tendency to involve fewer classroom interactions and to assess students' higher-order abilities less often, elements which are critical to the emergence of learning. Although the EMI teachers were aware of students' difficulties with English, these difficulties were not commonly taken into consideration, and accommodations were seldom made. Finally, the teachers' assessment practices were found to be mediated by variables such as discipline, course size, and the teachers' focus of assessment. The findings of this investigation have implications for the development and implementation of useful training programs in support of EMI teachers' professional development in assessment. [ABSTRACT FROM AUTHOR]

Abstract Background Age-related neurodegenerative diseases share a number of important pathological features, such as accumulation of misfolded proteins as amyloid oligomers and fibrils. Recent evidence suggests that soluble amyloid oligomers and not the insoluble amyloid fibrils may represent the primary pathological species of protein aggregates. Results We have produced several monoclonal antibodies that specifically recognize prefibrillar oligomers and do not recognize amyloid fibrils, monomer or natively folded proteins. Like the polyclonal antisera, the individual monoclonals recognize generic epitopes that do not depend on a specific linear amino acid sequence, but they display distinct preferences for different subsets of prefibrillar oligomers. Immunological analysis of a number of different prefibrillar Aβ oligomer preparations show that structural polymorphisms exist in Aβ prefibrillar oligomers that can be distinguished on the basis of their reactivity with monoclonal antibodies. Western blot analysis demonstrates that the conformers defined by the monoclonal antibodies have distinct size distributions, indicating that oligomer structure varies with size. The different conformational types of Aβ prefibrillar oligomers can serve as they serve as templates for monomer addition, indicating that they seed the conversion of Aβ monomer into more prefibrillar oligomers of the same type. Conclusions These results indicate that distinct structural variants or conformers of prefibrillar Aβ oligomers exist that are capable of seeding their own replication. These conformers may be analogous to different strains of prions.

Background: Blood or bone marrow transplantation (BMT) survivors with frailty are at a higher risk of subsequent mortality. Longitudinal trends in the frailty state are not known and could help identify vulnerable subpopulations at risk of subsequent adverse events. Methods: This study included a cohort of 470 autologous and allogeneic BMT recipients who had survived ≥2 years after BMT and completed a baseline questionnaire (t1) at a median of 7.3 years after BMT and a follow‐up questionnaire (t2) 13.2 years after t1. The main outcome was change in frailty state between t1 and t2. Frailty phenotype was defined as exhibiting ≥3 of the following characteristics: clinically underweight, exhaustion, low energy expenditure, slow walking speed, and muscle weakness. The following categories of change in frailty state were evaluated: worsened, improved, and stable. Results: Of the 470 participants, 36.4% were aged ≥60 years at t1, and 50.6% were men. The prevalence of frailty increased from 4.8% at t1 to 9.6% at t2. Worsening was observed in 18.8% of patients, and improvement was reported in 9.7%. Pre‐BMT exposure to vincristine (odds ratio [OR], 2.1; 95% CI, 1.3‐3.39) was associated with worsening. Female sex (OR, 1.5; 95% CI, 0.93‐2.4) was associated with a trend toward worsening. Pre‐BMT exposure to vincristine (OR, 2.79; 95% CI, 1.44‐5.43), a history of chronic graft‐versus‐host disease (OR, 2.58; 95% CI, 1.2‐5.5), and grade 3 and 4 chronic health conditions at t1 (OR, 2.1; 95% CI, 1.08‐4.33) were associated with frailty at t2. Conclusions: In a cohort of BMT survivors who were followed longitudinally for a median of 20.6 years from BMT, the frailty status worsened for approximately20% over a 13‐year timespan. BMT survivors who are at risk for worsening frailty could benefit from targeted interventions. In bone marrow transplantation survivors who were followed for a median of 13 years, the prevalence of frailty increased from 4.8% to 9.6%. Exposure to vincristine before bone marrow transplantation was associated with 2.1 times greater odds (95% CI, 1.3‐3.39 greater odds) of a worsening frailty state. [ABSTRACT FROM AUTHOR]

Abstract Background Amyloid-related degenerative diseases are associated with the accumulation of misfolded proteins as amyloid fibrils in tissue. In Alzheimer disease (AD), amyloid accumulates in several distinct types of insoluble plaque deposits, intracellular Aβ and as soluble oligomers and the relationships between these deposits and their pathological significance remains unclear. Conformation dependent antibodies have been reported that specifically recognize distinct assembly states of amyloids, including prefibrillar oligomers and fibrils. Results We immunized rabbits with a morphologically homogeneous population of Aβ42 fibrils. The resulting immune serum (OC) specifically recognizes fibrils, but not random coil monomer or prefibrillar oligomers, indicating fibrils display a distinct conformation dependent epitope that is absent in prefibrillar oligomers. The fibril epitope is also displayed by fibrils of other types of amyloids, indicating that the epitope is a generic feature of the polypeptide backbone. The fibril specific antibody also recognizes 100,000 × G soluble fibrillar oligomers ranging in size from dimer to greater than 250 kDa on western blots. The fibrillar oligomers recognized by OC are immunologically distinct from prefibrillar oligomers recognized by A11, even though their sizes overlap broadly, indicating that size is not a reliable indicator of oligomer conformation. The immune response to prefibrillar oligomers and fibrils is not sequence specific and antisera of the same specificity are produced in response to immunization with islet amyloid polypeptide prefibrillar oligomer mimics and fibrils. The fibril specific antibodies stain all types of amyloid deposits in human AD brain. Diffuse amyloid deposits stain intensely with anti-fibril antibody although they are thioflavin S negative, suggesting that they are indeed fibrillar in conformation. OC also stains islet amyloid deposits in transgenic mouse models of type II diabetes, demonstrating its generic specificity for amyloid fibrils. Conclusion Since the fibril specific antibodies are conformation dependent, sequence-independent, and recognize epitopes that are distinct from those present in prefibrillar oligomers, they may have broad utility for detecting and characterizing the accumulation of amyloid fibrils and fibrillar type oligomers in degenerative diseases.

The development of a well-defined Fe catalyst and its application to the regio- and stereoselective 1,4-hydrosilylation of 1,3-dienes is reported. The study provides the first example of accessing a characterized low-valent Fe catalyst by controlled reductive elimination from a readily accessible Fe precatalyst.

Background & Aims Loss of claudin 18 (CLDN18), a membrane-spanning tight junction protein, occurs during early stages of development of gastric cancer and associates with shorter survival times of patients. We investigated whether loss of CLDN18 occurs in mice that develop intraepithelial neoplasia with invasive glands due to infection with Helicobacter pylori , and whether loss is sufficient to promote the development of similar lesions in mice with or without H pylori infection. Methods We performed immunohistochemical analyses in levels of CLDN18 in archived tissues from B6:129 mice infected with H pylori for 6 to 15 months. We analyzed gastric tissues from B6:129S5- Cldn18 tm1Lex/Mmucd mice, in which the CLDN18 gene was disrupted in gastric tissues (CLDN18 -knockout mice), or from control mice with a full-length CLDN18 gene (CLDN18 +/+; B6:129S5/SvEvBrd) or heterozygous disruption of CLDN18 (CLDN18 +/−; B6:129S5/SvEvBrd) that were infected with H pylori SS1 or PMSS1 at 6 weeks of age and tissues collected for analysis at 20 and 30 weeks after infection. Tissues from CLDN18 -knockout mice and control mice with full-length CLDN18 gene expression were also analyzed without infection at 7 weeks and 2 years after birth. Tissues from control and CLDN18 -knockout mice were analyzed by electron microscopy, stained by conventional methods and analyzed for histopathology, prepared by laser capture microdissection and analyzed by RNAseq, and immunostained for lineage markers, proliferation markers, and stem cell markers and analyzed by super-resolution or conventional confocal microscopy. Results CLDN18 had a basolateral rather than apical tight junction localization in gastric epithelial cells. B6:129 mice infected with H pylori , which developed intraepithelial neoplasia with invasive glands, had increasing levels of CLDN18 loss over time compared with uninfected mice. In B6:129 mice infected with H pylori compared with uninfected mice, CLDN18 was first lost from most gastric glands followed by disrupted and reduced expression in the gastric neck and in surface cells. Gastric tissues from CLDN18-knockout mice had low levels of inflammation but increased cell proliferation, expressed markers of intestinalized proliferative spasmolytic polypeptide-expressing metaplasia, and had defects in signal transduction pathways including p53 and STAT signaling by 7 weeks after birth compared with full-length CLDN18 gene control mice. By 20 to 30 weeks after birth, gastric tissues from uninfected CLDN18-knockout mice developed intraepithelial neoplasia that invaded the submucosa; by 2 years, gastric tissues contained large and focally dysplastic polypoid tumors with invasive glands that invaded the serosa. Conclusions H pylori infection of B6:129 mice reduced the expression of CLDN18 early in gastric cancer progression, similar to previous observations from human gastric tissues. CLDN18 regulates cell lineage differentiation and cellular signaling in mouse stomach; CLDN18-knockout mice develop intraepithelial neoplasia and then large and focally dysplastic polypoid tumors in the absence of H pylori infection. Graphical abstract [ABSTRACT FROM AUTHOR]