Dose Determination of Activated Charcoal in Management of Amitriptyline-Induced Poisoning by Reversed-Phase High-Performance Liquid Chromatography

Purpose: To assess the doses of activated charcoal currently used in the management of acute amitriptyline-induced drug poisoning and explore the possibility of using lower doses.Methods: Albino male Wistar rats, weighing 200 ± 20 g, were used for the study. The animals were divided into four groups of eight animals each. The concentration of amitriptyline in rat plasma was measured by high performance liquid chromatography (HPLC) for dose determination of activated charcoal. Chromatograms were established with acetonitrile: 70 mM KH2PO4 buffer (60: 40, v/v) solvent system on an Xterna® ms C18 SUM column (5 μm, 3.9 × 150 mm) and pH was adjusted to 4.5 with ortho-phosphoric acid. Mobile phase flow rate was 1 ml/min and ultraviolet (UV) detection was at 293 nm. Validation of the method was performed to determine its selectivity, linearity, precision, as well as limits of detection (LOD) and of quantification (LOQ).Results: Standard curves were linear, r2 = 0.996, for amitriptyline over the concentration range 10 - 60 ng/ml. Recovery (98.3 to 100.85 %) was in the selected concentration range of 10 - 60 ng/ml. The LOD and LOQ of the method for amitriptyline were 0.109 and 0.332 μg/ml, respectively. The validated method was successfully applied to measure plasma concentrations of amitriptyline and to measure the doses of activated charcoal currently used in the management of acute amitriptyline drug poisoning.Conclusion: The proposed RP-HPLC method enables determination of amitriptyline with good separation and resolution of the chromatographic peaks. Validation revealed that the method is sensitive, accurate and selective. Using half of the standard dose of the activated charcoal gave a comparable effect to the standard dose in reducing drug concentration in the blood. While, using quarter of the standard dose of activated charcoal does not have a cleared effect.Keywords: Amitriptyline, Activated charcoal, Drug poisoning, Reversed-phase high-performance liquid chromatograph

A supervisory loop approach to fulfill workspace constraints in redundant robots

An approach based on geometric invariance and sliding mode ideas is proposed for redundancy resolution in robotic systems to fulfill configuration and workspace constraints caused by robot mechanical limits, collision avoidance, industrial security, etc. Some interesting features of the proposal are that: (1) it can be interpreted as a limit case of the classical potential field-based approach for collision avoidance which requires using variable structure control concepts, (2) it allows reaching the limit surface of the constraints smoothly, depending on a free design parameter, and (3) it can be easily added as a supervisory block to pre-existing redundancy resolution schemes. The algorithm is evaluated in simulation on a 6R planar robot and on the freely accessible 6R robot model PUMA-560, for which the main features of the method are illustrated.This research is partially supported by DISICOM project PROM-ETEO 2008/088 of Generalitat Valenciana (Spain), research project DPI2011-27845-C02-01 of the Spanish Government (Spain), Technical University of Valencia (Spain), and the Argentinian Government (UNLP 11I127, CONICET PIP 112-200801-0, ANPCyT PICT 2007 00535).Gracia Calandin, LI.; Sala, A.; Garelli, F. (2012). A supervisory loop approach to fulfill workspace constraints in redundant robots. Robotics and Autonomous Systems. 60(1):1-15. https://doi.org/10.1016/j.robot.2011.07.008S11560

The Burden of Obesity in Saudi Arabia: A Real-World Cost-of-Illness Study

Mouaddh Abdulmalik Nagi,1,2 Ziyad Saeed Almalki,3,* Montarat Thavorncharoensap,4,5,* Sermsiri Sangroongruangsri,4 Saowalak Turongkaravee,4 Usa Chaikledkaew,4,5 Abdulhadi M Alqahtani,6 Lamis S AlSharif,6 Ibrahim A Alsubaihi,7 Abdulaziz I Alzarea,8 Mohammed M Alsultan9 1Doctor of Philosophy Program in Social, Economic, and Administrative Pharmacy, Department of Pharmacy, Faculty of Pharmacy, Mahidol University, Bangkok, Thailand; 2Department of Pharmacy, Faculty of Medical Sciences, Aljanad University for Science and Technology, Taiz, Yemen; 3Department of Clinical Pharmacy, Prince Sattam bin Abdulaziz University, Riyadh - Al-Kharj, Saudi Arabia; 4Department of Pharmacy, Faculty of Pharmacy, Mahidol University, Bangkok, Thailand; 5Mahidol University Health Technology Assessment (MUHTA) Graduate Program, Mahidol University, Bangkok, Thailand; 6Clinical Research Department, Research Center, King Fahad Medical City, Riyadh, Saudi Arabia; 7Department of Clinical Trials Support and Development, Saudi National Institute of Health, Riyadh, Saudi Arabia; 8Department of Clinical Pharmacy, Al-Jouf University College of Pharmacy, Sakaka, Saudi Arabia; 9Department of Pharmacy Practice, College of Clinical Pharmacy, Imam Abdulrahman bin Faisal University, Dammam, Saudi Arabia*These authors contributed equally to this workCorrespondence: Ziyad Saeed Almalki, Department of Clinical Pharmacy, Prince Sattam bin Abdulaziz University, P.O. Box: 173, Riyadh - Al-Kharj, 11942, Saudi Arabia, Email [email protected] Montarat Thavorncharoensap, Department of Pharmacy, Faculty of Pharmacy, Mahidol University, Bangkok, 10400, Thailand, Email [email protected]: The rising prevalence of obesity in the Kingdom of Saudi Arabia (KSA) poses a significant public health challenge. Estimates of the economic cost of obesity are crucial for prioritizing healthcare interventions, guiding policy choices, and justifying budget allocations aimed at reducing obesity prevalence. This study aimed to estimate the cost of obesity in the KSA in 2022.Methods: A prevalence-based cost-of-illness approach was used to determine the cost of obesity. This analysis encompasses 29 diseases, namely obesity and twenty-eight diseases attributable to obesity. Both direct and indirect costs were considered. The annual cost of treatment for each obesity-attributable disease was obtained from the hospital records of one tertiary hospital in the KSA. Data on direct non-medical costs were obtained from the patient survey. The human capital approach was used to estimate the indirect costs of morbidity and mortality.Results: The total economic burden of obesity (2022 values) was estimated at US$116.85 billion from a societal perspective and US$109.67 billion from a healthcare system perspective. From a societal perspective, the total direct medical cost accounted for the largest portion of the total cost (94%). In terms of direct medical costs, the cost of treating diseases attributable to obesity was substantially greater than the cost of treating obesity itself. According to the sensitivity analysis, the total cost ranged from 3.4% of the country’s Gross domestic product (GDP) when the unit cost of treatment was reduced by 74% to 9.5% of the country’s GDP when the prevalence of obesity and its comorbidities was reduced by 5%.Conclusion: Obesity imposes a substantial economic burden on the healthcare system and society in the KSA. Interventions aimed at promoting healthier lifestyles to reduce the prevalence and incidence of obesity and its comorbidities are highly warranted to alleviate the impact of obesity in the country.Keywords: body mass index, cost-of-illness, economic burden, obesity, Saudi Arabi

K-differenced vector random fields

Click on the DOI link to access the article (may not be free).A thin-tailed vector random field, referred to as a K-differenced vector random field, is introduced. Its finite-dimensional densities are the differences of two Besse! functions of second order, whenever they exist, and its finite-dimensional characteristic functions have simple closed forms as the differences of two power functions or logarithm functions. Its finite-dimensional distributions have thin tails, even thinner than those of a Gaussian one, and it reduces to a Linnik or Laplace vector random field in a limiting case. As one of its most valuable properties, a K-differencexl vector random field is characterized by its mean and covariance matrix functions just like a Gaussian one. Some covariance matrix structures are constructed in this paper for not only the K-differenced vector random field, but also for other second-order elliptically contoured vector random fields. Properties of the multivariate K-differenced distribution are also studied

A learning skills course for the 1st year medical students: an experience at a Saudi medical school

Imran A Siddiqui,1 Khalid A Bin Abdulrahman,2 Mohammed A Alsultan3 1Department of Medical Education and Postgraduate Studies, Saudi Commission for Health Specialties, Riyadh, Saudi Arabia; 2College of Medicine, Al-Imam Muhammad Ibn Saud Islamic University (IMSIU), Riyadh, Saudi Arabia; 3College of Medicine, King Saud bin Abdulaziz University for Health Sciences, Riyadh, Saudi Arabia Background: Every year nearly 1,500 students enter into medical program after passing high school and national aptitude exams. However, many students experience frustration, failure, and psychological morbidities like stress, depression, and anxiety because they are not aware of their learning styles or do not have effective learning skills and strategies. The College of Medicine of Al-Imam Muhammad ibn Saud Islamic University has adopted the outcome based, community oriented, Spiral Curriculum. Although the curriculum is innovative, on the other hand, it is very demanding. Objective: The purpose of this paper is to share educational structure and evaluation results of the course on effective learning and study skills for the 1st year medical students. Methods: To prepare our students in order to cope with this demanding but promising curriculum, we conducted an effective and comprehensive learning skills course for 16 weeks in the first semester of year 1 in the medical program. Performance of each student was assessed and the course evaluation was done by students at the end of the course. Results: The attendance of the students throughout the course was over 90%. The average performance of students in the summative assessment was 78% and the course was generally liked by the students. Discussion: Students overall had a positive attitude toward the learning skills course. Majority of the students showed interest in attending the sessions regularly and realized the significance of this course to improve their learning skills. Keywords: medical students, learning skills, Saudi student

Optimal placement of reclosers in a radial distribution system for reliability improvement

There is a need for the optimal positioning of protective devices to maximize customers satisfaction per their demands. Such arrangement advances the distribution system reliability to maximum achievable. Thus, radial distribution system (RDS) reliability can be improved by placing reclosers at suitable feeder sections. This article presents comprehensive details of an attempt to determine the reclosers’ optimal location in an RDS to maximize the utility profit by reliability improvement. Assessment of different reliability indices such as SAIDI, SAIFI, CAIFI, CAIDI, etc., with recloser placement, exhibits a considerable improvement in these indices in contrast with the absence of recloser. Consequently, a new bidirectional formulation has been proposed for the optimized arrangement of reclosers’. This formulation efficiently handles the bidirectional power flow, resulting from distributed generation (DG) unit (s) in the system. The proposed model has been solved for a test system by utilizing the Genetic algorithm (GA) optimization method. Later, test results conclude that reclosers’ optimal placement contributes significantly towards utility profit with minimum investment and outage costs.Full Tex

Awareness, Beliefs, and Psychological Impact of Patients with Alopecia Areata in Saudi Arabia: A Multi-Center Study

Nasser Abdullah Almulhim,1 Heba Yousef Alojail,2 Mohammed Abdullah Aljughayman,2,* Fatimah Hussain Almarri,2,* Norah Hamad Alsultan,1,* Latifah Adel Albash,1,* Sara Khalid Almukhaimar,1,* Ali Abduljalil Alkhamis,1,* Mohammed Abdullah Albaqshi,1,* Amnah Ali Alkhawajah1,* 1College of Medicine, King Faisal University, Alahsa, Saudi Arabia; 2Department of Dermatology, King Faisal University, Alahsa, Saudi Arabia*These authors contributed equally to this workCorrespondence: Amnah Ali Alkhawajah, College of Medicine, King Faisal University, Alahsa, Saudi Arabia, Tel +966551364812, Email [email protected]: Alopecia Areata (AA) is a complex autoimmune condition characterized by long-term inflammatory non-scarring patches of hair loss on the face, scalp, and body. Its development involves a combination of genetic, immunological, and environmental factors, making it challenging to understand and treat. This study aims to assess the awareness, beliefs, and psychological impact of patients with Alopecia Areata.Patients and Methods: This cross-sectional study was conducted in Eastern and Central provinces of Saudi Arabia and utilized online questionnaires to evaluate knowledge, beliefs, and psychological effects of patients with Alopecia Areata. These questionnaires were distributed using social media platforms.Results: This study enrolled 248 patients with Alopecia Areata (AA), of whom 38.7% were aged 31– 40 years and 55.2% were males. The majority were Saudis (98.4%), married (54%), and residing in the Central Region (60.1%). Nearly half (48.8%) were employed in non-medical fields, and 30.6% were vocational school graduates. Healthcare providers were the main source of AA information (52.8%), with most patients aware of AA’s seriousness, curability, and quality of life impact, though many had low knowledge and experienced negative psychological effects such as shyness, anxiety, and depression.Conclusion: Despite low self-rated knowledge, most patients recognized AA as serious and requiring treatment. Psychological well-being was heavily impacted by AA severity, quality of life, disease duration, and treatment efficacy. Although many patients showed improved AA status and good medication compliance, adverse psychological effects persisted, highlighting the need for larger studies to better understand and address these issues.Keywords: alopecia areata, dermatology, knowledge, Middle East, mental health, surve

Synergistic amplification of catalytic hydrogen generation by a thin-film conducting polymer composite

This work reports a composite of polyIJ3,4-ethylenedioxythiophene) (PEDOT) that is notably more catalytically active for hydrogen generation than the industry-standard benchmark catalyst, Pt, under the same conditions. A PEDOT thin-film containing nanoparticulate Ni (nano-Ni) and reduced graphene oxide (rGO) in the specific molar ratio of 5.6 (C; PEDOT) : 1 (Ni) : 5.2 (C; other), (photo)catalytically generated H2 at 3.6 mA cm−2 (including ca. 0.2 mA cm−2 due to the light illumination) after 3 h at −0.75 V (vs. Ag/AgCl) in 0.05 M H2SO4/0.2 M Na2SO4 under 0.25 sun. A control nano-Ni/rGO film containing the same quantities of nano-Ni and rGO but without any PEDOT, yielded 2.1 mA cm−2, indicating that the PEDOT synergistically amplified the above result by 71%. Other ratios of the above PEDOT composite produced notably lower activities. Control PEDOT, PEDOT/nano-Ni, and PEDOT/rGO films were an order of magnitude less catalytically active. A control bare Pt electrode produced only 2.2 mA cm−2 under the same conditions. Studies suggested the origin of the synergistic amplification to involve the PEDOT electrically connecting the largest number of active sites by the shortest, most efficient pathways for hole transport. These results confirm the proposition that thin-film conducting polymers involving very specific, optimum ratios of catalyst density to thickness may synergistically amplify catalysis