Sinteza i biološka evaluacija nekih pirimidina, pirimido[2,1-b][1,3]tiazina i tiazolo[3,2-a]pirimidin derivata

4,6-Diamino-1H-pyrimidine-2-thione (1) was used for the preparation of the pyrimidine derivatives 2-5. Compound 5 was cyclized to produce pyrimido[2,1-b][1,3]thiazine derivatives 6, which was condensed with p-chlorobenzaldehyde to give compound 7. The latter compound was reacted with hydroxylamine to give isoxazolo[4,5-d]thiazino[2,3-a]pyrimidines 8. Compound 8b was treated with 2-chloroethyl methyl ether to afford compound 9. Similarly, compound 3 was reacted with chloroacetic acid to give thiazolo[3,2-a]pyrimidine 10, which was condensed with p-chlorobenzaldehyde to give compound 11. Compound 11 was condensed with hydroxylamine to give isoxazolo[4,5-d]thiazolo[2,3-a]pyrimidine 12. Compound 12b was treated with 2-chloroethyl methyl ether to afford compound 13. The biological evaluation of some prepared products showed that many of them revealed promising antimicrobial activity.4,6-Diamino-1H-pirimidin-2-tion (1) upotrebljen je kao ishodni spoj u sintezi derivata pirimidina 2-5. Spoj 5 je cikliziran u pirimido[2,1-b][1,3]tiazin derivat 6, koji je kondenziran s p-klorbenzaldehidom u spoj 7. Produkt 7 je u reakciji s hidroksilaminom dao izoksazol[4,5-d]tiazino[2,3-a]pirimidin 8. Spoj 8b je u reakciji s 2-kloretil metil eterom dao spoj 9. Slično je spoj 3 reagirao s kloroctenom kiselinom i dao tiazol[3,2-a]pirimidin 10, koji je kondenziran s p-klorbenzaldehidom u produkt 11. Spoj 11 je kondenzacijom s hidroksilaminom dao izoksazol[4,5-d]tiazolo[2,3-a]pirimidin 12. Spoj 12b je s 2-kloretil metil eterom dao produkt 13. Biološka evaluacija pokazuje da neki od sintetiziranih produkata imaju antimikrobno djelovanje

Morphological and molecular characterization of L-methioninase producing Aspergillus species

Six species of L-methioninase producing Aspergillus species, isolated from Egyptian soil, were selected for comprehensive morphotypic and molecular characterization. Based on morphological and physiological features, these isolates were identified as Aspergillus flavipes, Aspergillus carneus, Aspergillus flavus, Aspergillus tamari, Aspergillus oryzae, and Aspergillus parasiticus. Regarding to the maximum enzyme productivity by A. flavipes, it was selected as authentic strain for ribosomal ribonucleic acid (rRNA) primer design. Using primer combinations for 18S rRNA and internal transcribed spacers (ITS)1 amplification, these isolates gave the same polymerase chain reaction (PCR) amplicon size, revealing the relative molecular identity. Moreover, using ITS2 primers, among the six isolates, Aspergillus flavipes EK and A. carneus displayed PCR products on agarose gel, approving the actual morphological and biochemical similarities of these two isolates, A. flavipes group. By sequencing of ITS1-5.8S-ITS2 region, blasting and alignment from the data base, A. flavipes EK showed a typical identity to gene bank deposited A. flavipes isolates. The rRNA sequence of A. flavipes EK was deposited to genbank under accession number JF831014.Key words: Aspergillus, morphological descriptions, 18 S rRNA, internal transcribed spacers (ITS) regions

The impact of information/decision support systems (I/DSS) in debt management: The Egyptian experience.

The introduction of technology-based tools into developing countries is usually impeded by a number of potential problems. The problems become murkier when the context of the issue, such as external debt management, where technology is to be used, does not have a standard textbook of rules and procedures to follow. The principle problems encountered during the course of our research for this thesis hinged the issue of possible inapplicability of information technology (IT), especially information and decision support systems (I/DSS). This is also the case for other tools and techniques built and used by developed countries in the developing world. The great deal of difference in the context of use; content of the systems; and the attitudes of the parties involved in the process forms the basis for our argument. The research was intended to draw on the lessons learned by the Cabinet Information and Decision Support Center (IDSC) during the introduction I/DSS for improving the decision making process in developing countries. Moreover, the research intended to tackle the issue of using I/DSS in a totally new context, other than for very structured purposes such as manufacturing and the like, and a challenging environment such as those in developing countries where difficulties of implementation and use are more in context, content and cultural issues than technological ones. The research would then show implications, identify problems and challenges and try to develop generalizations and recommendations. The research, since its initial phases, had to consider the forces of centralization versus decentralization and the organizational structure of decision making especially at the top level. Other issues such as I/DSS project planning and implementation; organizational dynamics and the research at the organizational level related to national policy; and technical information systems development were taken into consideration. This experience could be viewed as a documentation phase where the Egyptian Cabinet IDSC and the Central Bank of Egypt (CBE) together hove built, implemented and sustained state-of-the-art I/DSS in the process of establishing a powerful Egyptian debt management office. The analysis of these experiences displays many lessons for the implementation of sophisticated systems under conditions of extreme difficulty. It offers insight into a number of problems that concern designers, implementors, users, and researchers in I/DSS use in managing development planning and socio-economic change especially in developing countries. It also delves into important aspects related to project planning and implementation, organizational dynamics and the effective use of accurate, timely and relevant information in development planning. We conclude this thesis with on analytical framework that gives detailed methods and guidelines for future implementation of similar programs in developing countries that might wish to benefit from the experience of the Cabinet of Egypt IDSC

Popularity of the Consumption of Dietary Supplements and its Associated Factors among Students in an Egyptian University: A Cross-sectional Study

BACKGROUND: Dietary supplements (DS) use has substantially become prevalent worldwide. However, a limited number of studies have addressed the consumption of DS among college students. AIM: The objective of the study was to explore the prevalence of DS use among college students in an Egyptian college, their motives for DS use, and the association with sociodemographic and lifestyle factors. METHODS: A cross-sectional study was conducted on 180 (18–25 years) college students at Helwan University. A self-administered questionnaire that included sociodemographic and lifestyle characteristics, DS use, commonly used types, reasons for use, and sources of information was employed. RESULTS: More than two-thirds of the participants (117 students) have used DS with no difference among sex except for the types and motives for use (p < 0.001). The most used types were amino acids and proteins, multivitamins and minerals, and weight-loss herbals. Male students mainly used amino acids and proteins (54.7%), multivitamins, and minerals (17.2%), for building muscles (50%), gaining more energy (14%), and maintaining good health (14%). Female students consumed multivitamins and minerals (35.8%), weight-loss herbals (28.3%), for health promotion (34%) and weight management (28.3%). The main sources of information were the internet, health-care providers, and coaches. Male users depended primarily on the internet; however, female users received information from health-care providers (p < 0.001). Practicing exercise, non-smoking, and dietary patterns were associated with DS use. CONCLUSION: DS use is remarkably common among college students in Egypt since their freshmen year. The findings highlight an urgent need to raise students’ awareness regarding the appropriate use of DS from reliable sources to control DS use and prevent adverse effects

One-pot multi-component synthesis of tetrahydroquinazolinones via Biginelli condensation using molecular iodine as a catalyst

Tetrahydroquinazolinone derivatives were synthesized in moderate to high yields via one‐pot three component Biginelli reaction of dimedone, urea or thiourea and corresponding aromatic aldehydes in the presence of molecular iodine as an efficient catalyst, in ethanol under reflux conditions. This protocol offers several advantages including good yields of products and easy experimental work‐up procedure

Antioxidant, antimicrobial and anti-cancer properties of silver nanoparticles biosynthesized using artichoke waste extract

In the present work, a green method for biosynthesis of silver nanoparticles (AgNPs) from artichoke processing is proposed. The formation of AgNPs spectrophotometrically confirmed by appearance of maximum peak at 430 nm. Transmission electron microscope revealed AgNPs with different shapes and average particle size (88.94 nm). Phytochemical and gas chromatography results indicated the presence of important compounds especially phenols and flavonoids in artichoke waste extract. AgNPs were tested to determine their potential antioxidant, antibacterial and anticancer activities. The results showed that AgNPs have high antioxidant capacity. Antibacterial test showed that AgNPs were capable of inhibiting Staphylococcus aureus, Bacillus cereus, Escherichia coli and Salmonella. AgNPs showed anticancer activity against breast cancer cell line with a decline in cells viability with increase of AgNPs concentration and IC50 (144.29μmole/ml). Based on these results and the benefits of phytochemicals detected in artichoke waste extract, this waste could be effectively used for silver nanoparticles preparation

Effect of FSW Parameters on The Microstructure and Mechanical Properties of T-joints between Dissimilar Al-Alloys

The main purpose of this research is to develop T-joints between the aluminum AA 2024-T4 and AA 7075-T6 using friction stir welding.  The effect of tool geometries, tool traveling speed, and rotational rate in the welded T-joints were investigated and discussed. Three different tools were used with different shoulder to pin ratios 3.28, 3.36, and 4.31. After optimization, the best tool dimension has used with the different rotational and welding speeds. Three tool traverse speeds of 50, 75, and 100 mm/min were used. Two rotation rates of 800 rpm and 1000 rpm were applied. After FSW, at a number of the above FSW parameters' combinations, macrostructure and microstructure analyses were done using optical microscopy. In order to have an insight into the mechanical properties, hardness measurements and tensile testing were carried out. Using small shoulder to pin ratio produced visually unacceptable T-joint. Opposite happened by using the tool with 4.31 of shoulder to pin ratio. Furthermore, the results showed sound T-welds with no obvious defects at high rotational rate of 1000 rpm with the two used traveling speeds. Asymmetric temperature distribution was observed between the two sides, advance side (AS) and retreating side (RS

Assessment of Quality of Life among Beta-Thalassemia Major Patients Attending the Hematology Outpatient Clinics at Cairo University Hospital

AIM: This paper aimed at assessing the quality of life (QoL) among beta (β)-thalassemia major patients using the short-form-36questionnaire (SF-36) and determining the factors associated with it. METHODS: A cross-sectional study was conducted among β-thalassemia major patients who were attending the hematology outpatient clinic at Cairo University Hospital using the consecutive sampling technique. Data were collected between October 2016 and March 2017. The QoL was assessed for patients aged ≥17 years. During the study period, a total number of 112 patients were included for participation. RESULTS: The mean age of the studied group was 18.32 ± 1.33 years. Most of the included patients (93.63%) had 1 monthly blood transfusion. The mean total score of SF-36 was 44.90 ± 7.54. Among the QoL domains of the studied patients, the “general health perception” domain was the most affected one with a mean score of (add the value of the score here), while the “vitality” domain was the least affected one. No statistically significant difference was reported between males and females regarding different QoL domains except for the “vitality” domain which mean score was significantly higher in males compared to females (p = 0.05). The age at onset of the disease and at first blood transfusion was the most documented factors to be positively correlated with the QoL among the studied patients. CONCLUSION: This study revealed that the QoL in thalassemia major patients is compromised. QoL assessment should be performed for all thalassemia patients to determine and implement the necessary interventions that focus on the affected domains

Establishing and characterizing a permanent magnet system for the prototype of NIS's Kibble balance

The Kibble balance experiment is used to redefine the kilogram as a unit of mass based on the Planck constant. To demonstrate and understand the basic principle of the Kibble balance, the National Institute of Standards (NIS)-Egypt has constructed a prototype Kibble balance that can measure gram-level masses with 0.01% relative uncertainty. Through the construction of this prototype, the challenges can be studied and addressed to overcome the weaknesses of NIS’s prototype. This study presents the design and construction of the prototype Kibble balance. It also focuses on the design and performance of the magnetic system, which is a crucial element of the Kibble balance. Analytical modeling and finite element analysis were used to evaluate and improve the magnet system. Several other aspects were also discussed, including the yoke’s material and enhancing the magnetic profile within the air gap of the magnet system. Over a vertical distance of 30 mm inside the air gap, the magnetic flux density was found to be 0.3 T, and the uniformity was found to be 8 x 10 -5