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Background: Student-centered learning strategy increases the likelihood of graduation of competent, self-dependent, and problem-solving physicians. The University of Bisha, College of Medicine (UBCOM) adopted self-directed learning (SDL) represented by problem-based learning (PBL), and directed self-learning (DSL) represented by team-based learning (TBL). Aim: To compare the students' performance in SDL and DSL among UBCOM students. Methodology: A total of 502 multiple choice questions (MCQs) from the mid-course and final exams were collected by the relevant subject experts from nine courses during the period from September 2020 till June 2023 that adopted PBL and TBL; 247 MCQs related to PBL and 255 related to TBL. Psychometric analysis was used to determine difficult, easy, and optimum questions (≤25%, ≥90%, and 26-89%, respectively). Point biserial as <0.19, 0.20-0.29, 0.30-0.39, and >0.40 which indicate poor, marginal, good, and excellent point biserial, respectively. Finally, the number of functional distractors was attempted by >5% of the candidates. Results: No significant differences were noted for the students' performance in MCQs related to PBL (representing self-directed, small group learning tool), and TBL (representing directed-self, large group learning tool) regarding difficulty index (DI), point biserial, and distractors functionality. Conclusion: It has been observed that there is no difference in students' performance whether PBL or TBL is used for learning Basic Medical Science courses. Small group learning such as PBL needs more resources in comparison to large group learning as in TBL, therefore any institute can decide on the adopted learning strategy depending on its resources and the number of students.

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Reductions of green gas emissions and the reuse/recycling of industrial byproducts are important for the mitigation of the environmental impact of the construction industry. The replacement of ordinary Portland cement (OPC) is a concrete binder with industrial byproducts that possess sufficient cementitious and pozzolanic properties, such as ground granulated blast furnace slag (GBS) and fly ash. This critical review analyzes the effect of some of the most critical parameters on the development of the compressive strength of concrete or mortar that consists of combinations of alkali-activated GBS and fly ash as binders. The review includes the effects of the curing environment, the proportions of GBS and fly ash in the binder, and the concentration of the alkaline activator on strength development. The article also reviews the effect of exposure as well as the age of samples at the time of exposure to acidic media on the development of concrete strength. The effect of acidic media on mechanical properties was found to depend not only on the type of acid but also on the alkaline activator solution, proportions of GBS and fly ash in the binder, and the age of the sample at the time of exposure, among other factors. As a focused review, the article pinpoints important findings such as the change in compressive strength over time when mortar/concrete is cured in an environment that permits the loss of moisture versus curing in a system that retains the alkaline solution and keeps reactants available for hydration and the development of geopolymerization products. The relative contents of slag and fly ash in blended activators have a significant impact on strength development. Research methods used include a critical review of the literature, a comparison of reported research findings, and identifying reasons for agreement or disagreement of findings.

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Prostate cancer is the second most common cancer diagnosed in men and the fifth-leading cause of cancer death in men worldwide. Like any solid tumor, the hypoxic microenvironment of prostatic cancer drives hypoxia-inducible factors (HIFs) to mediate cell adaptions to hypoxic conditions. HIFs direct different signaling pathways such as PI3K/Akt/mTOR, NOX, and Wnt/ß-Catenin to tumor progression depending on the degree of hypoxia. HIFs regulate cytoskeleton protein expression, promoting epithelial-mesenchymal transition (EMT), which occurs when cancer cells lose cell-to-cell adhesions and start invasion and metastasis. Through activating pathways, the hypoxic microenvironment maintains the self-renewal, potency, and anti-apoptotic function of prostate cancer cells and induces tumor metastasis and transformation. These pathways could serve as a potential target for prostate cancer therapy. HIFs increase the expression of androgen receptors on cancer cells maintaining the growth and survival of prostate cancer and the development of its castration resistance. In this review, we elaborate on the role of hypoxia in prostatic cancer pathogenesis and different hypoxia-induced mechanisms.

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The effect of submerging geopolymer mortar samples in highly acidic solution for 7-, 28-, and 90-days on stability of mass and the development of compressive strength development was assessed experimentally. The mortar binder consisted of GGBS or blends of GGBS and fly ash activated using combinations of NaOH and Na2SiO3 solutions, and samples were cured in room temperature. It was found that maintaining mortar samples continuously under sulfuric acid doesn't cause reduction compressive strength or mass from one age to the other, up to 90 days. While decalcification, delaumination, and formation of calcium salts due to sulfate attack may have affected mass and strength, submerging samples under water supported formation of geopolymerization products C-A-S-H and N-A-S-H, and consequently increased the mass and compressive strength of cubic mortar samples with fly ash + GGBS blended binder. The resistance of mortar to sulfuric acid remained consistent when mortars were prepared using GGBS:fly ash ratio of 3:1, equal amounts of GGBS and fly ash, and GGBS as sole binder. When geopolymer mortar samples made with each of the three binders was left exposed to air after casting, compressive strength increased from 7- to 28-days after casting, but at 90-days, all mortar samples experienced decrease in compressive strength relative to the 28-day values. The relatively high content of GGBS (≥ 50%) and absence of curing water in relatively dry conditions caused shrinkage cracking and decrease in compressive strength.

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INTRODUCTION: The published studies discussing the prognostic factors for expected sexual function after coronary artery bypass graft (CABG) are still limited. AIM: Examining the correlation between the European System for Cardiac Operative Risk Evaluation (EuroSCORE) and the abridged form of International Index of Erectile Function questionnaire (IIEF-5), as a quick and inexpensive tool for the cardiologist to predict the sexual function after CABG. MAIN OUTCOME MEASURES: Validated standardized questionnaire commonly used by cardiologists in identifying appropriate weight to various risk factors related to adult cardiac operations. METHODS: Preoperatively patients were evaluated as regards to the sexual function by (IIEF-5) and pharmaco-penile duplex ultrasound. Moreover all patients were evaluated bu EuroSCORE. Six months after surgery, the erectile function of all patients was revaluated according to the same preoperative procedures. The patients were categorized with EuroSCORE as follows: The low-risk group (EuroSCORE 0­2), the medium-risk group (EuroSCORE 3­5), and the high-risk group (EuroSCORE 6 plus). RESULTS: The EuroSCORE was negatively correlated with the IIEF-5 score (r = -0.224, P = 0.025 or rs = -0.259, P = 0.009). Moreover, low-risk patients had significantly higher IIEF-5 scores compared with medium-risk patients (mean standard deviation = 15.27 6.03 vs. 12.18 6.07, P < 0.05). CONCLUSIONS: There is an inverse correlation between the components of EuroSCORE and the IIEF-5 score. Patients with higher EuroSCORE had lower IIEF-5 scores and vice versa. The EuroSCORE is a useful, quick, and inexpensive tool that allows prediction of ED in those patients with coronary artery disease patients who are undergoing CABG.

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INTRODUCTION: A strong association between cardiovascular risk factors and erectile dysfunction (ED) was suggested. Coronary artery bypass grafting (CABG) is the gold standard for surgical myocardial revascularization. AIM: We herein evaluate the impact of vascular risk factors on postoperative sexual functions in patients undergo CABG. MAIN OUTCOME MEASURES: ED severity by the International Index of Erectile Function (IIEF-5) and penile duplex study. METHODS: The present study included 100 patients who underwent CABG. The patients were evaluated by an abridged form of the IIEF-5 questionnaire, followed by CABG. Six months after surgery the erectile function of all patients was re-evaluated utilizing the IIEF-5. RESULTS: Number of risk factors was significantly associated with postoperative change in IIEF-5 score (P = 0.02). A post hoc analysis of the association revealed that patients with one risk factor were significantly more likely to have increased IIEF-5 scores (N = 18), whereas those with two or more risk factors were significantly more likely to have decreased IIEF-5 scores (N = 21, P < 0.05). Furthermore, those with no risk factors were significantly more likely to be stable (N = 8) compared with those with more than two risk factors, who were more likely to have decreased scores (P < 0.05). The hierarchical logistic regression results showed that when examining all risk factors simultaneously, because of multicollinearity, only hyperlipidemia was significantly associated with postoperative ED (odds ratio [OR] = 11.33, confidence interval [CI] = 1.25, 102.82). Frequency of intercourse was also significantly associated with postoperative ED after controlling for risk factors (OR = 0.71, CI = 0.52, 0.97). CONCLUSIONS: This data clearly shows that the number of cardiovascular risk factors is an essential predictive factor for sexual function following surgery. Only hyperlipidemia may play a predictive role for the future sexual function of patients undergo CABG.

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INTRODUCTION: Erectile dysfunction and ischemic heart disease are common health problems that affect elderly individuals. Despite advances in treatment strategies, cardiopulmonary bypass (CPB) has been used for coronary artery bypass grafting (CABG) for over three decades for surgical myocardial revascularization. AIM: To discuss the difference between the on pump and the newer alternative-the off-pump CABG (OPCABG) surgery-on the sexual function. METHODS: This prospective study included 100 patients who underwent CABG. MAIN OUTCOME MEASURES: The patients were evaluated by an abridged form of International Index of Erectile Function questionnaire (IIEF-5), Pharmaco-Penile Duplex Ultrasound and finally by the European System for Cardiac Operative Risk Evaluation. The patients were underwent either on-pump CABG or OPCABG. Six months after surgery, the erectile function was revaluated according to the same preoperative measures. RESULTS: Patients included in the study were classified into two matched groups: group I-patients who underwent on-pump CABG (N = 50); and group II-patients who underwent OPCABG (N = 50). The frequency of intercourse was significantly higher in OPCABG (P < 0.05) after surgery. The mean +/- standard deviation of the IIEF-5 scores of the on-pump group postoperatively became 12.48 +/- 7.19 whereas it became 15.88 +/- 6.67 in the off-pump group (P < 0.05). Moreover, the number of patients who reported postoperative improvement of their IIEF-5 score was significantly higher in OPCABG group (N = 23) compared with the conventional on-pump CABG group (N = 13) (P < 0.05). There was no significant change in the duplex ultrasound after surgery between both groups. CONCLUSIONS: The OPCABG has a diminished impact on the sexual function of patients compared with the conventional on-pump CABG. Therefore, the type of operation can be considered a predictive factor of sexual function following CAB surgery.

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