Mahmoud Salah Khalil

Students’ perception towards the problem based learning tutorial session in a system-based hybrid curriculum

Objectives: To evaluate students’ perception towards the problem based learning (PBL) session in a system-based hybrid curriculum. Methods: We conducted a cross-sectional study in the College of Medicine, King Saud University, Saudi Arabia at the end of the 2012-2013 academic year. The survey questionnaire was self-administered, and examined perceptions of PBL session benefits, appropriate running of sessions, and tutor’s roles. Results: Out of 510 students, 275 (53.9%) completed the questionnaire. Most of the students reported that PBL sessions were helpful in understanding basic sciences concepts (p=0.04). In addition, they agreed that PBL sessions increased their knowledge of basic sciences (p=0.01). Most students reported that PBL sessions encouraged self-directed learning, collaborative learning, and improved decision making skills. However, 54.5% of students reported lack of proper training before starting the PBL sessions, and only 25.1% of students agreed that the teaching staff are well prepared to run the sessions. Most students used the internet (93.1%), lecture notes (76.7%), and books (64.4%) as learning resources. Most students reported repetition of topics between PBL sessions and lectures (p=0.07). Conclusion: The study highlighted the significant role of PBL in a system-based hybrid curriculum and helped students improve their knowledge and different learning skills. Students and staff training is required before the utilizing the PBL as an instructional method.

The relationship between non-functioning distractors and item difficulty of multiple choice questions: A descriptive analysis

Objectives: This study investigates the relationship between the presence of non-functioning distractors (NFDs) and the difficulty index of multiple choice questions (MCQs). Materials and Methods: The number of NFDs and difficulty index were correlated for each MCQ of Family Medicine Examination, College of Medicine, King Saud University (KSU) in three consecutive years (2010, 2011 and 2012). Results: The MCQs with more NFDs showed high difficulty index as compared to MCQs having less NFDs. The pattern of increasing difficulty index was 1NFD Conclusion: MCQs with a higher number of NFDs are easier than those with lower number of NFDs.

Effectiveness of longitudinal faculty development programs on MCQs items writing skills: A follow-up study

This study examines the long-term impact of the faculty development programs on the multiple choice question (MCQ) items’ quality leading to study its effect on the students’ overall competency level during their yearly academic assessment. A series of longitudinal highly constructed faculty development workshops were conducted to improve the quality of the MCQs items writing skills. A total of 2207 MCQs were constructed by 58 participants for the assessment of 882 students’ cognitive competency level during the academic years 2012–2015. The MCQs were analyzed for the difficulty index (P-value), discriminating index (DI), presence/absence of item writing flaws (IWFs), and non-functioning distractors (NFDs), Bloom’s taxonomy cognitive levels, test reliability, and the rate of students’ scoring. Significant improvement in the difficulty index and DI were noticed during each successive academic year. Easy and poor discriminating questions, NFDs and IWFs were decreased significantly, whereas distractor efficiency (DE) mean score and high cognitive level (K2) questions were increased substantially during the each successive academic year. Improved MCQs’ quality leaded to increased competency level of the borderline students. Overall, the longitudinal faculty development workshops help in improving the quality of the MCQs items writing skills of the faculty that leads to students’ high competency levels.

Histological and immunohistochemical effects of L-arginine and silymarin on TNBS-induced inflammatory bowel disease in rats.

Inflammatory bowel disease (IBD) is a chronic disease that affects quality of life. Various mediators are involved in IBD pathogenesis including inducible nitric oxide synthase (iNOS), nuclear factor kappa B (NF-κB), cytochrome c, heat shock protein 70 (HSP70) and tumor necrosis factor (TNF)-α. L-Arginine (L-Arg) can be depleted in IBD, and silymarin inhibits neutrophil infiltration, NF-κB, and TNF-α, which have crucial roles in inducing IBD. This study aimed to investigate whether silymarin and L-Arg supplementation decreases IBD progression in trinitrobenzine-sulfonic acid (TNBS)-induced colitis. Fifty adult male albino rats were randomized into five groups (10 animals per group): Group I rats orally received 100 mg silymarin/kg body weight once daily; Group II rats orally received 2 mg L-Arg/100 g body weight in 5 mL distilled water once daily; Group III rats rectally received 0.85 mL TNBS in 50% ethanol to induce colitis; Group IV rats were treated similar to group III and, on recovery from anesthesia, received silymarin as described for group I; and Group V rats were treated similar to group III and, on recovery from anesthesia, received L-Arg as described for group II. On day 7, the rats were anesthetized, and blood samples were collected to determine the serum concentrations of TNF-α. Laparotomy and total colectomy were performed for macroscopic, histological, and immunohistochemical investigations. The results showed that silymarin and L-Arg macroscopically and microscopically ameliorated TNBS-induced colitis; significantly decreased the serum levels of TNF-α; inhibited the colonic expression of iNOS, NF-κB, and cytochrome c; and increased expression of HSP70. Our results suggest that these complementary medicines could be used to supplement current treatments for IBD.

Histological and Immunohistochemical Basis of the Effect of Aminoguanidine on Renal Changes Associated with Hemorrhagic Shock in a Rat Model

Acute kidney failure is the main cause of death among patients with severe trauma due to massive blood loss and hemorrhagic shock (HS). Renal cell injury is caused by tissue ischemia. Renal ischemia initiates a complex and interconnected chain of events resulting in cell injury and renal cell necrosis. Nitric oxide plays a crucial role in renal function and can be inhibited by aminoguanidine (AG). We studied whether AG can ameliorate pathological renal changes associated with HS syndrome in a rat model and explored the AG protection mechanism. Rats were intraperitoneally injected with heparin sodium and mean arterial blood pressure was monitored. Animals were divided into three groups: control (without hemorrhage), with or without intra-arterially injected AG; HS (blood continuously withdrawn or reinfused to maintain an MABP of 35–40 mmHg); and HS with AG. We found that AG decreased plasma concentrations of urea, creatinine, and nitrates; ameliorated histological changes of HS-induced rats; and decreased the expressions of inducible nitrogen oxide synthase (iNOS), proapoptotic protein (BAX), and vitamin D receptors (VDR). AG ameliorated kidney injury by inhibiting iNOS resulting in decreased BAX and VDR expressions. Therefore, a therapeutic strategy targeting AG may provide new insights into kidney injury during severe shock.

Does coenzyme-Q have a protective effect against atorvastatin induced myopathy? A histopathological and immunohistochemical study in albino rats

INTRODUCTION In addition to their lipid-lowering effect, statins have pleiotropic effects that may extend their use to the treatment and prevention of various other diseases such as cancer, osteoporosis, multiple sclerosis, rheumatoid arthritis, type 2 diabetes, and Alzheimers disease. Consequently, the number of patients taking statins is expected to increase. A side effect of statins, statin-induced myopathy, which may result from reduced muscular coenzyme Q10 levels, limits their use. The current study investigates if supplementing with CoQ10 could ameliorate statin induced myopathy. MATERIALS AND METHODS Forty adult male albino rats were randomized into 4 groups, with 10 rats per group. The following was administered to the rats using oral gavage for 4 weeks: Group 1: 2 ml of 0.5% carboxymethyl cellulose once daily. Group 2: 100 mg/kg/ day coenzyme Q10 dissolved in 2 ml of cotton seed oil. Group 3: 10 mg/kg once daily atorvastatin dissolved in 0.5% carboxymethyl cellulose. Group 4: concomitantly received CoQ10 and atorvastatin similar to groups 2 and 3 respectively. Plasma creatine kinase levels were measured by using spectrophotometer. The right extensor digitorum longus muscle sections were stained for histological (Haematoxylin & Eosin, Masson trichrome and Phosphotungstic acid haematoxylin) and immunohistochemical (cytochrome C and Bax) examinations. Quantitative measures of cytochrome C and Bax were carried out using image analyzer. RESULTS Atorvastatin induced increased total creatine kinase, skeletal muscle variations in the sizes and shapes, necrosis, disorganization, nuclear pyknosis, karyorrhexis, karyolysis, dismantled plasma membrane, excess collagen fibers and lipid deposition in addition to loss of cross striation. Atorvastatin increased the intensity of the immune-positive reactions of cytochrome C and Bax. These changes were ameliorated by concomitantly giving coenzyme Q10. CONCLUSION CoQ10 may ameliorate atorvastatin induced skeletal muscle injury.

Vitamin D3 May Ameliorate the Ketoconazole Induced Adrenal Injury: Histological and Immunohistochemical Studies on Albino Rats.

Ketoconazole (KZ) is used widely for treating the superficial, systemic fungal activities and hyperandrogenemic states. Its uses are limited by its deleterious effect on histological structure and function of the adrenal cortex. This study investigates whether vitamin D3 supplement can ameliorate the morphological changes induced by KZ. Thirty four adult male albino rats were randomized into control group (Group I) which was subdivided into: control 1 (n=7) and control 2 (n=7): In control 1, rats were intraperitoneal (I.P) injected once with 1 ml of polyethylene glycol-400 for 15 consecutive days and control 2 rats were injected I.P with (1 μg/kg) of vitamin D3 for the same period. Group II (n=10): rats were I.P injected with KZ (10 mg/100 g of body weight) once daily for 15 days; Group III (n=10): rats were I.P concomitantly injected with KZ and vitamin D3 similar doses to animals in groups II and control 2 respectively. Blood samples were collected to determine plasma ACTH, corticosterone and aldosterone levels. The right adrenal specimens sections were stained with Haematoxylin & Eosin and Masson Trichrome for histological studies and treated with Bax, Ubiquitin and vitamin D receptors for immunohistochemical studies. KZ induced adrenal cortical morphological changes in forms of disturbed adrenocorticocyte cytological architecture, nuclear changes, and intracellular lipid accumulation. KZ also increased adrenal Bax and Ub but decreased the vitamin D receptors immunopositive staining expression, in addition to increased plasma ACTH as well as decreased corticosterone and aldosterone levels. These changes were ameliorated by supplementing with vitamin D3.

No Evidence of Association of the Arg72Pro p53 Gene Polymorphism with Cancer Risk in the Saudi Population: a Meta-Analysis.

BACKGROUND Earlier studies on the association between p53 codon 72 Arg>Pro polymorphism and cancer risk were inconclusive and conflicting for the Saudi population. Therefore, we performed a meta-analysis to investigate the relationship between the codon 72 Arg>Pro polymorphism and overall cancer risk in Saudi Arabia. MATERIALS AND METHODS We searched all eligible published studies and data were pooled together to perform the meta-analysis. Pooled odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated for homozygous, heterozygous, dominant and recessive genetic models. RESULTS A total of five eligible published studies covering 502 cancer cases and 784 healthy controls were included in the meta-analysis. No publication bias was detected in this study. The results suggested that the variant (Pro vs Arg: p=0.960; OR=1.004, 95% CI=0.852-1.183), homozygous (Pro.Pro vs Arg.Arg: p=0.970; OR=1.006, 95% CI=0.729-1.390), heterozygous (Arg.Pro vs Arg.Arg: p=0.473; OR=0.783, 95% CI=0.402-1.527) carriers were not associated with overall cancer risk. Similarly, dominant (Pro.Pro+Pro.Arg vs Arg.Arg: p=0.632; OR=0.886, 95% CI=0.540-1.454) and recessive (Pro.Pro vs Pro.Arg+Arg.Arg: p=0.269; OR=1.163, 95%CI=0.890-1.521) models also did not indicate increased risk of cancer. CONCLUSIONS The current meta-analysis suggests that the codon 72 Arg>Pro polymorphism of the p53 gene might not contribute to cancer susceptibility in Saudi population. Future well designed large case control studies are needed to validate our findings.