Search

Nada Al-Yousuf,1 Ebtisam Al Alawi,2 Abdulhameed Mahmood,3 Amani Alzayani,4 Hajer Al Sawad,4 Hasan Alsetri,5 Jalal Al-Mousawi,6 Khatoon Ali,4 Maryam Al Khayat,4 Reem Naser4 1Department of Ophthalmology, King Abdulla Medical City, Manama, Bahrain; 2The Eye Center, Manama, Bahrain; 3Department of Ophthalmology, Prince Sultan Military Medical City, Riyadh, Saudi Arabia; 4Department of Ophthalmology, Salmaniya Medical Complex, Manama, Bahrain; 5Department of Chemistry and Biochemistry, University of California, Los Angeles, CA, USA; 6Al-Mousawi Specialist Center, Manama, BahrainCorrespondence: Nada Al-YousufDepartment of Ophthalmology, King Abdulla Medical City, P.O. Box 26671, Adliya, BahrainTel +973 77310071Fax +973 77310001Email nyousuf10@gmail.comPurpose: To study the changing indications for Penetrating keratoplasty in Bahrain and to compare them with published data.Patients and Methods: A Retrospective review of available records of patients who underwent penetrating keratoplasty at a tertiary center in Bahrain (1996− 2015). The trend of each indication was analyzed. The study was subdivided into three periods for correlation purposes. Pearson Coefficient r and the p values were used for interpretation of data. The results were compared with similar studies.Results: A total of 298 patients underwent keratoplasty in the study period, which is from 1996 until 2015 (missing data 2009– 2011). Keratoconus was found to be the leading indication, accounting for 33% of the total cases, followed by trachoma 27%, followed by aphakic and pseudophakic bullous keratopathies 13%. Trachoma showed a statistically significant decreasing trend (p < 0.001), Keratoconus had an increasing trend (p< 0.001). Bullous keratopathy showed an increasing trend (p = 0.001) with an abrupt rise after 2012.Conclusion: Corneal scarring due to old trachoma was the leading indication for keratoplasty 20 years ago in Bahrain. However, due to improvement of health awareness, hygiene, and the socioeconomic status, this has regressed with keratoconus becoming the leading indication from 2002 onwards. A surge of bullous keratopathy was noted after 2012, placing it as the second commonest indication. This may be due to the introduction of phacoemulsification technique for cataract surgery, and perhaps because the nature of the institute being a teaching hospital. Keratoconus is the leading indication and showed an increasing trend. It is recommended to perform a keratoconus screening program for early detection and prevention.Keywords: keratoconus, bullous keratopathies, corneal graft, indications, cornea transplant, trachoma

Deyaa Mansouri,1 Ebtehal Khayat,2 Mohannad Khayat,3 Muteb Aboawja,4 Areej Aseeri,5 Faisal Banah,6 Khulood Alsiary,7 Lama Abdulaziz Rammal,7 Adel D Almalki,8 Mohammed Hasaballah9 1Hera General Hospital, Mecca, Saudi Arabia; 2Joint Program of Family Medicine, Mecca, Saudi Arabia; 3Joint Program of Community Medicine, Mecca, Saudi Arabia; 4King Faisal Medical City, Abha, Saudi Arabia; 5King Fahad Military Medical Complex, Dhahran, Saudi Arabia; 6Armed Hospital Southen Rigon, KhamisMushait, Saudi Arabia; 7King Abdulaziz Medical City, Jeddah, Saudi Arabia; 8King Salman Bin Abdulaziz Hospital, Riyadh, Saudi Arabia; 9King Faisal Hospital, Mecca, Saudi ArabiaCorrespondence: Deyaa MansouriHera General Hospital, Mecca, Saudi ArabiaEmail dr_deyaa@hotmail.comPurpose: The study aims to assess current practices of patients with diabetes to control blood glucose levels during Ramadan.Patients and Methods: A cross-sectional approach has been used for collecting data through a structured and interview-based questionnaire to assess the association between self-monitoring of blood glucose (SMBG) and hypoglycemia. The questionnaire has recorded information about demographics, duration of diabetes, and treatment of diabetes, and hypoglycemia complications faced during Ramadan. The primary outcomes of this study include frequency of SMBG during fasting in Ramadan and association of SMBG and hypoglycemia and break of fasting. However, the secondary outcomes include medications, glycemic control, and other influencing factors. The data was analyzed using Statistical Package of Social Sciences (SPSS) version 20.Results: The findings have shown that the majority of the patients used a combination of metformin+sulphonylurea (23.02%) following metformin+insulin (20.86%), insulin (12.94%), and metformin (8.63%). Whereas diet control, high or low blood sugar, insulin dose adjustment in fasting conditions were the most influential factors during Ramadan when the blood sugar levels were tested. Majority of the patients monitored their blood glucose level during pre-iftar (56.8%) following to hypoglycemia (30.2%), post-iftar (29.4%), and rarely monitored in afternoon (3.5%) despite that only 10.1% monitored their blood glucose on a daily basis. Patients who had symptoms of hypoglycemia and had to break their fasting at least once were 41% and 27.2%, respectively. There is a significant association between age and gender with symptoms of low blood sugar level. Additionally, a significant association between blood sugar monitoring and high blood sugar level has been shown (p=0.041), indicating that lack in daily blood sugar monitoring can increase the blood sugar level of a patient during Ramadan.Conclusion: The present study has helped in providing better understanding about the self-monitoring of blood glucose level and hypoglycemia. Furthermore, it also emphasizes the pre-Ramadan education about when to break their fasting along with frequency and timing of SMBG.Keywords: glycemic control, insulin, medication, metformin, sulphonylurea

Osama Abdelhakim Aly Ahmed,1,2 Ahmed Samir Zidan,1,3 Maan Khayat4 1Department of Pharmaceutics and Industrial Pharmacy, Faculty of Pharmacy, King Abdulaziz University, Jeddah, Saudi Arabia; 2Department of Pharmaceutics and Industrial Pharmacy, Faculty of Pharmacy, Minia University, Minia, Egypt; 3Department of Pharmaceutics and Industrial Pharmacy, Faculty of Pharmacy, Zagazig University, Zagazig, Egypt; 4Department of Pharmaceutical Chemistry, Faculty of Pharmacy, King Abdulaziz University, Jeddah, Saudi Arabia Objectives: The study aims at applying pharmaceutical nanotechnology and D-optimal fractional factorial design to screen and optimize the high-risk variables affecting the performance of a complex drug delivery system consisting of glimepiride–Zein nanoparticles and inclusion of the optimized formula with thermoresponsive triblock copolymers in in situ gel. Methods: Sixteen nanoparticle formulations were prepared by liquid–liquid phase separation method according to the D-optimal fractional factorial design encompassing five variables at two levels. The responses investigated were glimepiride entrapment capacity (EC), particle size and size distribution, zeta potential, and in vitro drug release from the prepared nanoparticles. Furthermore, the feasibility of embedding the optimized Zein-based glimepiride nanoparticles within thermoresponsive triblock copolymers poly(lactide-co-glycolide)-block-poly(ethylene glycol)-block-poly(lactide-co-glycolide) in in situ gel was evaluated for controlling glimepiride release rate. Results: Through the systematic optimization phase, improvement of glimepiride EC of 33.6%, nanoparticle size of 120.9 nm with a skewness value of 0.2, zeta potential of 11.1 mV, and sustained release features of 3.3% and 17.3% drug released after 2 and 24 hours, respectively, were obtained. These desirability functions were obtained at Zein and glimepiride loadings of 50 and 75 mg, respectively, utilizing didodecyldimethylammonium bromide as a stabilizer at 0.1% and 90% ethanol as a common solvent. Moreover, incorporating this optimized formulation in triblock copolymers-based in situ gel demonstrated pseudoplastic behavior with reduction of drug release rate as the concentration of polymer increased. Conclusion: This approach to control the release of glimepiride using Zein nanoparticles/triblock copolymers-based in situ gel forming intramuscular implants could be useful for improving diabetes treatment effectiveness. Keywords: glimepiride, Zein, nanoparticles, quality by design, in situ implants

This study investigated the heat transfer characteristics of nanofluid nucleate and film boiling experimentally. To this end, Al2O3 and SiO2 deionized water-based nanofluids were prepared with three volumetric concentrations of 0.1%, 0.3%, and 0.5%. Boiling experiments were conducted on a circular and polished copper surface with a diameter of 25 mm. The results illustrated that the addition of nanoparticles to the base fluid reduced the heat transfer coefficient of nucleate boiling. Boiling of nanofluids elevated surface wettability and the critical heat flux was significantly higher than that of pure deionized water. The Al2O3 deionized water-based nanofluid with a volumetric concentration of 0.5% had the best performance, with a critical heat flux of 44.56% higher than that of pure deionized water. The presence of nanoparticles in the deionized water-based nanofluid improved the heat transfer coefficient of film boiling. As demonstrated by the results, the stable film boiling for nanofluids began with a more significant difference in wall superheat temperature than pure deionized water. Among the investigated concentrations, the volumetric concentration of 0.5% yielded the best performance for both nanofluids such that the minimum heat fluxes of Al2O3 and SiO2 deionized water-based nanofluids increased by 35.01% and 34.40%, respectively, compared to pure deionized water. [ABSTRACT FROM AUTHOR]

The purpose of this study was to demonstrate the feasibility of percutaneous fluoroscopically-guided transcervical retrograde access into the thoracic duct following unsuccessful transabdominal cisterna chyli cannulation to perform thoracic duct embolization for the treatment of chylothorax. Five patients, including three (60%) women and two (40%) men, with median age of 62 years, underwent percutaneous transcervical thoracic duct access and embolization after failed transabdominal cisterna chyli cannulation for the treatment of chylothorax. In all patients, fluoroscopically-guided percutaneous transcervical retrograde access into the distal thoracic duct was achieved using a 21-gauge needle and an 0.018-inch wire. Following advancement of a microcatheter, retrograde lymphangiography was performed to identify the location of thoracic duct injury. A combination of 2:1 ethiodized oil to cyanoacrylate mixtures, platinum microcoils, or stent-grafts were used to treat the chylous leaks. Technical successes, procedure durations, fluoroscopy times, blood losses, immediate adverse events, clinical successes, and follow-up durations were recorded. Technical success was defined as cannulation of the distal thoracic duct using a transcervical approach followed by treatment of the thoracic duct injury. Adverse events were classified according to the Society of Interventional Radiology guidelines. Clinical success was defined as resolution of the presenting chylothorax. Percutaneous transcervical retrograde thoracic duct access and treatment was technically successful in all patients (n=5). Median procedure duration was 173 minutes (range: 136-347 minutes) with a median fluoroscopy time of 94.7 minutes (range: 47-125 minutes). Median blood loss was 10 mL (range: 5-20 mL). No minor or major adverse occurred. Clinical success was achieved in all patients (n=5). Median follow-up was 372 days (range: 67-661 days). Percutaneous fluoroscopicallyguided transcervical retrograde thoracic duct access is an effective and safe method to perform thoracic duct embolization following unsuccessful transabdominal cisterna chyli cannulation for the treatment of chylothorax. [ABSTRACT FROM AUTHOR]

Plastic bronchitis is a poorly understood and uncommon diagnosis, arising from multiple etiologies. Traditional treatment consists of steroids and vasodilators, with thoracic duct embolization emerging as a new procedural therapy. Herein, abnormal lymphatic vessels were noted on lymphangiography in an adult patient with debilitating plastic bronchitis, but anterograde lymphatic access was not feasible due to the patient's morbid obesity and non-visualization of retroperitoneal lymphatics. After trans-venous thoracic duct access could not be established, direct transcervical thoracic duct access was performed. A thoracic duct stent-graft was placed, excluding the abnormal bronchial lymphatics and maintaining physiologic anterograde flow through the central lymphatics. At three-month follow-up, the patient's condition had resolved. [ABSTRACT FROM AUTHOR]

In this study, a three-dimensional and non-isothermal model of a polymer electrolyte membrane (PEM) fuel cell according to the multiphase mixture method was employed to analyze the influence of microporous layer (MPL) characteristics on water saturation and fuel cell performance. The modeled domain is divided into several regions comprising bipolar plate, gas channels, gas diffusion layers (GDLs), catalyst layers and polymer electrolyte membrane. A microporous layer has been sandwiched between the cathode GDL and the catalyst layer. In order to validate the model, the results were compared with the experimental data and a good agreement was observed. The results show that by placing the microporous layer between GDL and catalyst layer, a discontinuity appears in the liquid saturation and the species concentration at the contact surface of the layers. Therefore, the liquid water distribution in porous layers alongside the performance of the fuel cell largely depends on both structural and wetting properties of MPL. According to the results obtained, increasing the MPL porosity leads to decrease in the liquid water saturation, thereby improving the cell performance, while increasing the MPL thickness reduces the cell performance. Moreover, an MPL with a higher contact angle and gas permeability enhances the fuel cell performance due to the facilitation of water removal and reactant transport. [ABSTRACT FROM AUTHOR]

In this paper, an assumption used in the recent work of the author and his contributors considers the long-term concrete damage of the Dez arch dam as a homogeneous and isotropic process, was investigated in more detail and was adjusted. To this end, the vertical dam sections were divided into nine and six subsections along the thickness and height directions of the dam, respectively. In each subsection, a transversely isotropic damaged elastic constitutive law was considered for diagnostic analyses. Following the previous authors’ mentioned work, an optimization procedure (minimization of a certain error function) accompanied with an inverse thermal analysis was carried out. That analysis was performed within the framework of finite element (FE) method. Mentioned error function was defined as the sum of the squared residuals. Residuals were set as difference between nodal recorded displacements with inverse pendulums of the dam and the corresponding computed ones with the proposed model. Parameters considered as unknowns in the present inverse analysis, which have contributions in that above-mentioned error function, were the five independent elastic moduli presented in the formulation of the earlier mentioned transversely isotropic damaged elastic constitutive law: two Young’s moduli: one in the planes parallel to the up and down stream surfaces of the dam, called in-plane and the other in the perpendicular planes to those planes, named out-of-plane Young’s modulus; two Poisson’s ratios (in-plane and out-of-plane); and one shear modulus (out-of-plane). These parameters were identified performing numerous thermal inverse analyses. Obtained results revealed that the long-term damage of concrete of the Dez dam is a heterogeneous and anisotropic phenomenon because that the magnitude of the mentioned error function was obtained smaller than the corresponding value in the previous study which had been performed before based on the homogeneous and isotropic damage evolution assumption. [ABSTRACT FROM AUTHOR]

The article describes the case of a male patient who presented with severe early infantile encephalopathy resulting from early post-zygotic WDR45 somatic mutation. Topics discussed include brief clinical description of the patient, the confirmation of the mutation by Sanger sequencing, the analysis of the mutation in the patient's lymphocytes by microfluidic digital polymerase chain reaction (PCR) array technique, and the recommended treatment approach for WDR45 male patients.

In the present paper, conceptual duct shape design for kinetic energy extraction with hydrokinetic turbines is discussed. The goal is to find a single-passage axisymmetric geometry that holds stable flow with maximum kinetic energy flux at duct throat. For finding the optimum duct shape, the fluid flow was numerically simulated in a wedge shaped space with Flow-Simulation Software. In a multi-stage conceptual design, tabulated configurations were employed to study each geometrical characteristic separately. These include curvature of profile camber, trailing edge shape, profile tip shape, and duct exit cross sectional area. The revolved profile of each duct consists of a well constrained composite curve with few degrees of freedom. The Sketcher environment of SolidWorks Software provides a feasible method of rebuilding constrained curves. Duct shape optimization was performed based on successive flow simulation and approximation of optimum geometric dimension at optimum flow condition. The drag coefficients were compared with available experiments. Based on the numerical simulations with needle shaped leading edge, the duct throat velocity can be increased. Inversely, the flow blockage can reduce the kinetic energy flux at duct throat. The optimum duct shape has shown the greatest frictional drag coefficient and the minimum flow separation. [ABSTRACT FROM AUTHOR]