Preparation and Characterization of Poly(methyl methacrylate) Particles by Combined Dispersion and Emulsion Polymerization

Ibrahim Badr,Hadjira Lahmar,Chariya Kaewsaneha,Salima Saidi-Besbes,Abdelhamid Elaissari 한국고분자학회 2018 Macromolecular Research Vol.26 No.9

Monodispersed poly(methyl methacrylate) (PMMA) nanoparticles were synthesized by combined dispersion and emulsion polymerization, using aqueous alcohol (methanol/water) as the dispersion medium. The influence of the dispersion medium ratio, stabilizer concentration, and initiator type and concentration on the colloidal stability, particle size, size distribution, and %conversion, was investigated. Submicron PMMA particles with a size of approximately 760 nm with a narrow size distribution, high conversion (91%) and good stability throughout the polymerization were obtained using a 50/50 methanol/water ratio, 1wt% 2,2’-azobisisobutyronitrile (based on monomer), and 1wt% polyvinylpyrrolidone (based on medium). With increasing the polarity of the dispersion medium (30/70 methanol/water ratio), the size and conversion of PMMA particles decreased to 345 nm and 72%, respectively.

Maxillomandibular Advancement and Upper Airway Stimulation: Extrapharyngeal Surgery for Obstructive Sleep Apnea

유명상,Badr Ibrahim,Robert Wayne Riley,Stanley Yung Chuan Liu 대한이비인후과학회 2020 Clinical and Experimental Otorhinolaryngology Vol.13 No.3

There are many ways to categorize surgery for obstructive sleep apnea (OSA), one of which is to distinguish between intrapharyngeal and extrapharyngeal procedures. While the general otolaryngologist treating OSA is familiar with intrapharyngeal procedures, such as uvulopalatopharyngoplasty and tongue base reduction, extrapharyngeal sleep operations such as maxillomandibular advancement (MMA) and upper airway stimulation (UAS) have evolved rapidly in the recent decade and deserve a dedicated review. MMA and UAS have both shown predictable high success rates with low morbidity. Each approach has unique strengths and limitations, and for the most complex of OSA patients, the two in combination complement each other. Extrapharyngeal airway operations are critical for achieving favorable outcomes for sleep surgeons.

Factors affecting in vitro embryo production: insights into dromedary camel

Adel R. Moawad,Ibrahim M. Ghoneim,Gamal M. Darwish,Magdy R. Badr,Diya A. El-Badry,Abou Bakr A. EL-Wishy 한국동물생명공학회(구 한국동물번식학회) 2020 Journal of Animal Reproduction and Biotechnology Vol.35 No.2

The Dromedary camel (Camelus dromedaries) is an important species because of its ability to produce good quality meat, milk, and fibers under harsh environmental conditions. Camels are also crucial for transportation, racing, and as draft animals in agriculture. Therefore, dromedary camels play a critical role in the economy for millions of people living in the arid part of the world. The inherent capability of camels to produce meat and milk is highly correlated with their reproductive performance. Compared with other domestic species, the reproductive efficiency in camelids is low. Although recent reproductive technologies such as in vitro fertilization (IVF) and somatic cell nuclear transfer (SCNT) have been successfully applied to camelids and the birth of live offspring following these technologies has been reported; in vitro embryo production (IVP) has lagged in this species. The development of the IVP system for dromedary camels may be a useful tool for the genetic improvement of this species. IVP in farm animals includes three main steps; in vitro maturation (IVM) of an oocyte, IVF of a matured oocyte, and in vitro culture (IVC) of fertilized oocyte up to the blastocyst stage. This review aims to summarize various factors that influence oocyte quality, IVM, and in vitro embryo development in dromedary camel.

Factors affecting in vitro embryo production: insights into dromedary camel

Adel R. Moawad,Ibrahim M. Ghoneim,Gamal M. Darwish,Magdy R. Badr,Diya A. El-Badry,Abou Bakr A. EL-Wishy 사단법인 한국동물생명공학회 2020 한국동물생명공학회지 Vol.35 No.2

The Dromedary camel (Camelus dromedaries) is an important species because of its ability to produce good quality meat, milk, and fibers under harsh environmental conditions. Camels are also crucial for transportation, racing, and as draft animals in agriculture. Therefore, dromedary camels play a critical role in the economy for millions of people living in the arid part of the world. The inherent capability of camels to produce meat and milk is highly correlated with their reproductive performance. Compared with other domestic species, the reproductive efficiency in camelids is low. Although recent reproductive technologies such as in vitro fertilization (IVF) and somatic cell nuclear transfer (SCNT) have been successfully applied to camelids and the birth of live offspring following these technologies has been reported; in vitro embryo production (IVP) has lagged in this species. The development of the IVP system for dromedary camels may be a useful tool for the genetic improvement of this species. IVP in farm animals includes three main steps; in vitro maturation (IVM) of an oocyte, IVF of a matured oocyte, and in vitro culture (IVC) of fertilized oocyte up to the blastocyst stage. This review aims to summarize various factors that influence oocyte quality, IVM, and in vitro embryo development in dromedary camel.

Influence of a New Dietary Supplement on the Parameters of Functional Preparation, Working Capacity and Processes of Renewal in Athletes at the Work Performance in the Anaerobic-Glycolytic Zone of Energy-Supply

( S. Oliynyk ),( V. Sazonov ),( V. Shevchenko ),( S. Semenov ),( Mansour Bin Ibrahim Sulaiman ),( Arwa M. Badr El-Din ) 체육과학연구원 2010 International Journal of Applied Sports Sciences Vol.22 No.2

The authors have conducted the study on the influence of a new dietary supplement "Antilactate" (DS "Antilactate") on the parameters of working capacity and functional preparation of skilled athletes at a test load of sub-maximum power in the anaerobic zone of energy-supply and on the after-load renewal processes. Sixteen male athletes participating in Greco-Roman style wrestling were involved in the study; 10 men made up a test group, and six a control one. The study was conducted during the "crash" microcycle at the special preparatory stage of the base period. The duration of the microcycle, which was aimed at the improvement of athlete performance, was 7 days. The training loads during the mentioned microcycle were provided mostly at the account of anaerobic glycolytic mechanisms of energy-supply. The athletes from the test group were taking the DS "Antilactate" on a 7-day course. A daily dosage of the DS "Antilactate" substance - malate mono[(2-dimethylamino)ethyl ether] of succinic acid - made up 2.0 g. The athletes from the control group were taking a placebo under a similar pattern. To evaluate the working capacity and the preparation level of the tested athletes, we used a 30-second Wingate bicycle ergometer anaerobic test, which was conducted twice - at the start of the microcycle, during which the athletes were taking the DS "Antilactate" or the placebo, and at its termination. The development of renewal processes following the test load implementation was evaluated under the indices of lactate, urea, after-products of lipid peroxidation, hemoglobin and erythrocyte content in the athlete`s capillary blood. It was determined that a course (over a period of 7 days) administration of the DS "Antilactate" during the "crash" microcycle at the special preparatory period did not exert a significant influence on the parameters of working capacity and functional preparation of the athletes who performed work at sub-maximum power in the anaerobic zone of physical loads. Meanwhile, the intake of the tested dietary supplement would promote body restoration after anaerobic glycolytic loads at sub-maximum power, which was proved by the rise in the rate of the blood lactate elimination during a leisure period following the performance of test loads, absence of blood hemoglobin decrease and excessive activation of lipid peroxidation specified by intensive training loads in the athletes from the test group, who administered the DS "Antilactate". The findings allow us to consider it appropriate to employ this parapharmaceutical in the practice of skilled athletes practicing different sports with the predominant glycolytic mechanism of work energy-supply.