Postexamination item analysis of undergraduate pediatric multiple-choice questions exam: implications for developing a validated question Bank.

INTRODUCTION: Item analysis (IA) is widely used to assess the quality of multiple-choice questions (MCQs). The objective of this study was to perform a comprehensive quantitative and qualitative item analysis of two types of MCQs: single best answer (SBA) and extended matching questions (EMQs) currently in use in the Final Pediatrics undergraduate exam. METHODOLOGY: A descriptive cross-sectional study was conducted. We analyzed 42 SBA and 4 EMQ administered to 247 fifth-year medical students. The exam was held at the Pediatrics Department, Qena Faculty of Medicine, Egypt, in the 2020-2021 academic year. Quantitative item analysis included item difficulty (P), discrimination (D), distractor efficiency (DE), and test reliability. Qualitative item analysis included evaluation of the levels of cognitive skills and conformity of test items with item writing guidelines. RESULTS: The mean score was 55.04 ± 9.8 out of 81. Approximately 76.2% of SBA items assessed low cognitive skills, and 75% of EMQ items assessed higher-order cognitive skills. The proportions of items with an acceptable range of difficulty (0.3-0.7) on the SBA and EMQ were 23.80 and 16.67%, respectively. The proportions of SBA and EMQ with acceptable ranges of discrimination (> 0.2) were 83.3 and 75%, respectively. The reliability coefficient (KR20) of the test was 0.84. CONCLUSION: Our study will help medical teachers identify the quality of SBA and EMQ, which should be included to develop a validated question bank, as well as questions that need revision and remediation for subsequent use.

Modulation of autophagy, apoptosis and oxidative stress: a clue for repurposing metformin in photoaging.

Long-term sun exposure is the commonest cause of photoaging, where mutual interplay between autophagy, oxidative stress, and apoptosis is incriminated. In combating photoaging, pharmacological approaches targeted to modulate autophagy are currently gaining more ground. This study aimed to examine repurposing metformin use in such context with or without the antioxidant coenzyme Q10 (coQ10) in ultraviolet A (UVA) irradiation-induced skin damage. The study was conducted on 70 female CD1 mice that were randomly assigned into seven groups (10/group): normal control, vehicle-treated-UVA-exposed mice, three metformin UVA-exposed groups (Topical 1 and 10%, and oral 300 mg/kg), topical coQ10 (1%)-treated mice, and combined oral metformin with topical coQ10-treated UVA-exposed mice. After UVA-exposure for 10 weeks (3 times/week), macroscopic signs of photoaging were evaluated. Mice were then euthanized, and the skin was harvested for biochemical estimation of markers for oxidative stress, inflammation, matrix breakdown, and lysosomal function. Histopathological signs of photoaging were also evaluated with immunohistochemical detection of associated changes in autophagic and apoptotic markers. Metformin, mainly by topical application, improved clinical and histologic signs of photoaging. This was associated with suppression of the elevated oxidative stress, IL-6, matrix metalloproteinase 1, and caspase, with induction of cathepsin D and subsequent change in anti-LC3 and P62 staining in skin tissue. In addition to metformin antioxidant, anti-inflammatory, and antiapoptotic activities, its anti-photoaging effect is mainly attributed to enhancing autophagic flux by inducing cathepsin D. Its protective effect is boosted by coQ10, which supports their potential use in photoaging.

Differential Modulation of Autophagy Contributes to the Protective Effects of Resveratrol and Co-Enzyme Q10 in Photoaged Mice.

BACKGROUND: In photoaging, the accumulation of ultraviolet (UV)-induced oxidative damage leads to the characteristic hallmarks of aging. Here arises the importance of autophagy as a cellular degradation process that cleans the cells of defective or aged organelles and macromolecules, thus maintaining cellular homeostasis. In spite of this, the exact impact of autophagy in photoaging is still elusive. OBJECTIVE: To evaluate the protective effects of resveratrol and/or co-enzyme-Q10 against the UVA-induced alterations and to explore the role of autophagy in their proposed benefits. METHODS: Sixty female mice were randomly divided into normal control, untreated UVA-exposed, resveratrol (50mg/kg), co-enzyme-Q10 (100mg/kg), and resveratrol/co-enzyme-Q10-treated UVA-- exposed groups. Clinical signs of photoaging were evaluated using a modified grading score and the pinch test. Skin malondialdehyde and reduced glutathione were assessed as markers of oxidative stress. Tissues were examined for histopathological signs of photodamage, and autophagic changes were determined by immunohistochemical detection of LC3 and P62 in the different cells of the skin. RESULTS: UVA-exposure increased the oxidative stress with subsequent epidermal and dermal injury. This was associated with the stimulation of autophagy in the keratinocytes and inhibition of autophagic flux in the fibroblasts and infiltrating macrophages. Both drugs corrected the impaired pinch test, macro-and microscopic changes, and exhibited distinct staining patterns with anti-LC3 and P62 in the different cell types denoting autophagic modulation. CONCLUSION: Changes in autophagic flux are strongly implicated in photoaging associated skin damage and the differential modulation of autophagy by resveratrol and, to a lesser extent by Co-enzyme- Q10, is partially involved in their therapeutic benefits.