A Model for Computer Supported Learning in Undergraduate Education

Reflecting on an earlier observation by Dr. Herb Thompson (Department of Economics) that most of us had to teach ourselves how to teach* , I realized early on in my career that the best way to describe my role as a teacher is that of a learning facilitator. Sometimes that entails leading the way, and other times it requires pointing directions and getting out of the way

A Comparative Study on the Active Constituents, Antioxidant Capacity and Anti-Cancer Activity of Cruciferous Vegetable Residues

أجريت هذه الدراسة لتقييم كفاءة وفعالية مخلفات أربعة أنواع من خضروات العائلة الصليبية (البراسيكا) تم ستخلاصهم بمذيبين (الميانولي  - المائي) وهم كاتالي البروكولي ، كرنب بروكسل ، القرنبيط ، الفجل الأحمر. وتم تقييم المستخلصات من حيث محتواها الكلي من المركبات الفعالة مثل الفينولات و الفلاڤونيدات والتانينات وڤيتامين سي واتعرف عليها بالـ HPLC ودراسة نشاطاتها المضادة للأكسدة بأكثر من طريقة مثل الـ DPPH· والـ Fe2+-chelating والـ Reducing power وكذلك دراسة كفاءتها في كبح جماح ومنع إنتشار وتكاثر ثلاثة أنواع من الخلايا السرطانية للإنسان علي النطاق المعملي مثل خلايا سرطان الكبد HePG2 و خلايا سرطان القولون HTC116 وخلايا سرطان الثدي MCF7. أظهرت النتائج أن المستخلص الميثانولي لمخلفات البروكولي وكرنب بروكسيل أعطي أعلي محتوي من المركبات الفعالة و أعلي نشاط مضاد للأكسدة في كبح جماح الشق الحر الـ DPPH· و وأعلي قدرات إختزلية ضد الحديديك الـ Reducing power. بينما أظهر المستخلص المائي لكل من كرنب بروكسيل والقرنبيط اعلى نشاط في عملية خلب الحديدوز الـ Fe2+-chelating. أكد تحليل HPLC للتعرف علي المركبات الفينولية الموجودة في مستخلصات مخلفات خضروات البراسيكا التي تم التعرف عليها أن المستخلص الميثانولي يمتلك كميات مرتفعة من الكاتشين والروتين والكيوماريك والبنزويك و الليتيولين. كما أظهر المستخلص الميثانولي لمخلفات كرنب بروكسيل تأثيراً مثبطاً و مانع للإنتشار وقاتل مع كافة أنواع الخلايا السرطانية وكان ذلك متبوعاً بالبروكولي والفجل الاحمر على التوالي. أكدت هذه النتائج أن مخلفات كرنب بروكسيل تحتوي على مركبات كيميائية فعالة يمكنها أن تمنع تكاثر الخلايا السرطانية. لذلك ، اقترحت هذه النتائج أن مخلفات خضروات البراسيكا يمكن إستخدامها كمضادات أكسدة قوية ومضادة لإنتشار الخلايا السرطانية وذلك في تطبيقات الصناعات الغذائية و الدوائية.This study is pointed out to estimate the effectiveness of two solvents in the extraction and evaluating the active ingredients and their antioxidant activity as well as anti-cancer efficiency. Therefore, residues from four different Brassica vegetables viz. broccoli, Brussels sprout, cauliflower, and red cherry radish were extracted using two procedures methods: methanolic and water crude extracts. Methanol extracts showed the highest content of total phenolic (TP), total flavonoids (TF), and total tannins (TT) for broccoli and Brussels sprouts residues. Methanolic extract of broccoli and Brussels sprouts residues showed the highest DPPH· scavenging activity (IC50 = 15.39 and 18.64 µg/ml). The methanol and water extracts of Brussels sprout residues showed the highest chelating activity (IC50 = 11.77 and 5.94 µg/ml) and exhibited the highest reducing power (EC50 =14.38 and 20.18 µg/ml) with broccoli respectively. The HPLC analysis of phenolic compounds confirmed that the methanol extract of all the residues examined possessed high amounts of catchine, rutin, cumaric, benzoic, and luteolin. The methanol extract at 100 µg/ml of Brussels sprouts residues displayed a rise cytotoxic effect on HePG2 (80.40%), MCF7 (75.49%) and HCT116 (22.74%) followed by broccoli and red cherry radish, respectively. This result confirmed that Brussels sprouts residue contain effective chemical compounds that can inhibit the proliferation of cancer cells. Therefore, these results proposed that those Brassica vegetable residues might be beneficial as a potent antioxidant and anticancer agents and strongly recommended as fixing in constituent's food applications and pharmaceutical industries

Low Incidence of Androgen Receptor Mutation Among Egyptian Children with Androgen Resistance

Introduction: In Egypt, disorders of sex development (DSD) constitute a significant entity among the birth defect list. Previous studies have reported that end organ androgen unresponsiveness, i.e. Androgen resistance, was the most prevalent underlying mechanism among Egyptian 46,XY DSD cases. Based on cytogenetic and hormonal diagnostic criteria as well as few sporadic case reports, it was proposed that androgen receptor (AR) defects [i.e. Androgen insensitivity syndrome (AIS), OMIM#300068] might constitute a major etiology within this category. However, this has never been systematically ascertained through an AR molecular diagnostic approach. Aim of the Work: The current study aimed to assess the role of AR mutations as an underlying etiology among a sample of Egyptian 46,XY DSD pediatric patients presenting with androgen end organ unresponsiveness. Patients and Method: In the current study, 21 children [ag

Evaluation of cytotoxic activity of live toxoplasma gondii tachyzoites and toxoplasma antigen on MCF-7 human breast cancer cell line

The aim of this study was to investigate the cytotoxic potency of live Toxoplasma gondii tachyzoites as well as Toxoplasma antigen on MCF-7 human breast cancer cell line. Cancer cell lines are considered an essential preliminary step towards in-vitro investigation of the potential antineoplastic impact of novel chemotherapeutic agents. Pathogens, including viruses, bacteria, and parasites are noticeably under investigation, considering their potential antineoplastic activity. Some have attained a steady position in the clinical field as hepatitis B virus, human papilloma virus and BCG immunization. Toxoplasma gondii is an apicomplexan parasite with promising antineoplastic activity. In this study, live Toxoplasma tachyzoites provoked a direct cytotoxic effect on MCF-7 in a dose dependent manner, while Toxoplasma antigen didn’t induce such impact. Skipping the direct cytotoxic effect of Toxoplasma antigen doesn’t totally divert the possible antineoplastic activity of Toxoplasma antigen. Potential alternative immune mediated mechanisms could be an alternative. Further in-vivo studies in different cancer models are mandatory to investigate the underlying mechanisms of antineoplastic activity of Toxoplasma gondi

High-power operation of quantum-dot semiconductor disk laser at 1180 nm

In this letter, we report on a high-power operation of an optically pumped quantum-dot semiconductor disk laser designed for emission at 1180 nm. As a consequence of the optimization of the operation conditions, a record-high continuous-wave output power exceeding 7 W is obtained for this wavelength at a heat-sink temperature of 2 °C. A wavelength tuning over a range of 37 nm is achieved using a birefringent filter inside the cavity

Recent advances in the field of vertical-external-cavity surface-emitting lasers

Vertical-external-cavity surface-emitting lasers (VECSELs) have proved to be versatile lasers which allow for various emission schemes which on the one hand include remarkably high-power multi-mode or single-frequency continuouswave operation, and on the other hand two-color as well as mode-locked emission. Particularly, the combination of semiconductor gain medium and external cavity provides a unique access to high-brightness output, a high beam quality and wavelength flexibility. Moreover, the exploitation of intra-cavity frequency conversion further extends the achievable radiation wavelength, spanning a spectral range from the UV to the THz. In this work, recent advances in the field of VECSELs are summarized and the demonstration of self-mode-locking (SML) VECSELs with sub-ps pulses is highlighted. Thereby, we present studies which were not only performed for a quantum-well-based VECSEL, but also for a quantum-dot VECSEL

The interplay between oat beta glucan, gut microbiota and gut-liver axis in treatment of obesity associated non-alcoholic steatohepatitis and Type II diabetes mellitus

14-22Dietary fibers regulate host health through various mechanisms related to their physicochemical structure and physiological properties in the gut. The interplay between diet, gut microbiota and human host appear to play a significant role in pathogenesis of obesity associated complications. This study was designed to unravel oat beta glucan modulatory effect on non-alcoholic steatohepatitis and type II diabetes mellitus in high fat fed rats and to explain possible pathomechanics involving gut microbiota and gut liver axis. Sixty male albino rats were included and randomly divided into four equal groups: control group; positive control group; diet induced obesity group; oat beta glucan treated group. All were subjected to assessment of glycemic profile; liver enzymes; serum trimethylamine-N-oxide levels; hepatic G-protein coupled receptor 43 relative gene expression. Histopathological examination of hepatic tissue was performed. Results revealed that oat beta glucan administration improved the biochemical changes. The histopathological findings confirmed the biochemical changes. Gut microbiota appeared to be highly implicated via its metabolites short chain fatty acids and trimethylamine. Our conclusion was that oat beta glucan was a successful compliance in the management strategy of hepatic steatosis and diabetes mellitus via modulating a number of gut microbial products

Remote Ischaemic Conditioning in STEMI Patients in Sub-Saharan AFRICA: Rationale and Study Design for the RIC-AFRICA Trial

Purpose: Despite evidence of myocardial infarct size reduction in animal studies, remote ischaemic conditioning (RIC) failed to improve clinical outcomes in the large CONDI-2/ERIC-PPCI trial. Potential reasons include that the predominantly low-risk study participants all received timely optimal reperfusion therapy by primary percutaneous coronary intervention (PPCI). Whether RIC can improve clinical outcomes in higher-risk STEMI patients in environments with poor access to early reperfusion or PPCI will be investigated in the RIC-AFRICA trial. // Methods: The RIC-AFRICA study is a sub-Saharan African multi-centre, randomized, double-blind, sham-controlled clinical trial designed to test the impact of RIC on the composite endpoint of 30-day mortality and heart failure in 1200 adult STEMI patients without access to PPCI. Randomized participants will be stratified by whether or not they receive thrombolytic therapy within 12 h or arrive outside the thrombolytic window (12–24 h). Participants will receive either RIC (four 5-min cycles of inflation [20 mmHg above systolic blood pressure] and deflation of an automated blood pressure cuff placed on the upper arm) or sham control (similar protocol but with low-pressure inflation of 20 mmHg and deflation) within 1 h of thrombolysis and applied daily for the next 2 days. STEMI patients arriving greater than 24 h after chest pain but within 72 h will be recruited to participate in a concurrently running independent observational arm. // Conclusion: The RIC-AFRICA trial will determine whether RIC can reduce rates of death and heart failure in higher-risk sub-optimally reperfused STEMI patients, thereby providing a low-cost, non-invasive therapy for improving health outcomes

Guidelines for the establishment and functioning of Animal Ethics Commitees (Institutional Animal Care and Use Committees) in Africa.

Animals are used for scientific purposes across Africa to benefit humans, animals or the environment. Nonetheless, ethical and regulatory oversight remains limited in many parts of the continent. To strengthen this governance framework, the Pan-African Network for Laboratory Animal Science and Ethics brought together experts from 12 African countries to create an Africa-centric practical guide to facilitate the establishment and appropriate functioning of Institutional Animal Ethics Committees across Africa. The Guidelines are based on universal principles for the care and use of sentient animals for scientific purposes, with consideration of the cultural, religious, political and socio-economic diversity in Africa. They focus on 11 key elements, including responsibilities of institutions and of the Institutional Official; composition of the Committee; its responsibilities, functioning and authority; ethical application and review processes; oversight and monitoring of animal care and use and of training and competence; quality assurance; and the roles of other responsible parties. The intent is for African institutions to adopt and adapt the guidelines, aligning with existing national legislation and standards where relevant, thus ensuring incorporation into practice. More broadly, the Guidelines form an essential component of the growing discourse in Africa regarding moral considerations of, and appropriate standards for, the care and use of animals for scientific purposes. The increased establishment of appropriately functioning animal ethics committees and robust ethical review procedures across Africa will enhance research quality and culture, strengthen societal awareness of animals as sentient beings, improve animal well-being, bolster standards of animal care and use, and contribute to sustainable socio-economic development