Experimental and theoretical performance evaluation of parabolic trough mirror as solar thermal concentrator to thermoelectric generators

This paper presents the prospects of harnessing radiative heat from the sun with a parabolic trough mirror, as a solar thermal concentrator, in comparison to the mathematical model and experimental quartz-halogen concentrator model for the electrical energy conversion utilizing thermoelectric generators (TEG). The construction and design of TEG-setup along with Parabolic trough mirrors and quartz-halogen lamps are presented. The Parabolic trough mirror used as a focal point at a distance of 19.05 cm. With eight quartz-halogen concentrated heat, the maximum performance achieved at ΔT of 11.8 K, Voc of 292 mV and Isc of 95.8 mA, recorded at the concentrated hot-side surface temperature of 317.8 K. When compared to the natural solar concentrated heat, higher temperature of 473.15 K at the hot-side surface temperature of TG was achieved. It is concluded that the heat concentration of the parabolic mirror increases with an increase in the intensity of heat using natural solar radiations. The Voc of 1.76 V and Isc of 1.1 A at a temperature difference of 110 K were measured, which are in good agreement with validated mathematical results. The parabolic through mirror utilized is smaller in size and thus collected lesser sun rays than the larger dish style mirror, and hence the heat in the focal point was very low, for better results, parabolic trough mirror with higher surface area would be important for future experiments

A novel Ph-sensitive liposome to trigger delivery of afatinib to cancer cells: Impact on lung cancer therapy

A novel drug delivery system based on cationic (CL) and pH-sensitive liposomes (PSL) for tyrosine kinase inhibitor afatinib (AFT) were developed to enhance tumor-targetability against NSCLC cells and therapeutic effect. Optimal lipid to drug ratio was selected to prepare AFT-loaded PSL and CL with desirable physiochemical properties based on particle size, drug encapsulation efficiency (EE%), stability and release profiles. Moreover, antitumor activity was performed in vitro on human lung cancer cells (H-1975) using a WST-1 assay and Annexin-V apoptosis assay. The mean particle size of the liposomes was less than 100 nm, and EE% was more than 50% with lipid to drug ratio of 1:0.5. Stability data showed that PSL and CL were physically stable for 1 months at 4 and 25oC. In vitro drug release study demonstrated the sustained release of AFT at pH 7.5; while PSL exhibited fast drug release in pH 5.5. This effect revealed that PSL showed pH-sensitive release behaviors. In addition, the in vitro cytotoxicity study was employed for AFT-loaded PSL due to optimal characterizations. Thus, in vitro anticancer activity revealed that AFT loaded-PSL triggered apoptosis in H-1975 cells. In addition, the inhibitory effect towards H-1975 and HCC-827 was observed, indicating, which indicated high antitumor activity of AFT-loaded PSL. Then, PSL might potentially create practical clinical strategies for better targetability and delivery of AFT for treatment of lung cancer

The role of hepatic progenitor cells in predicting response to therapy in Egyptian patients with chronic hepatitis C, genotype 4

Background: Interferon therapy is used as a line of treatment of chronic hepatitis C virus (HCV) in several areas of the world including Egypt.Objective: Our aim was to investigate the value of hepatic progenitor cells (HPCs) in predicting response of patients with chronic HCV, genotype 4 to pegylated interferon (PEGIFN) plus ribavirin (RBV) therapy.Methods: Pre-treatment liver biopsies obtained from 110 patients with chronic HCV, genotype 4 were examined immunohisto- chemically for HPCs using cytokeratin19. The mean number of HPCs as ductular reaction (DR) and as isolated progenitor cells (IPCs) was counted in each case. The patients were classified into: those with sustained virological response (SVR) and those who did not achieve SVR. The results were compared between the two groups. Also, the relationships between HPCs and other clinico-pathologic variables were estimated using multivariate analysis.Results: The mean number of HPCs was the only independent predictor of therapeutic response, being significantly higher in non-responders (P = 0 for DR and P = 0.03 for IPCs). On the other hand, fibrosis stage and steatosis were the only independent factors which showed a significant direct association with the mean number of HPCs in the form of DR and IPCs (P = 0 for each).Conclusion: The number of HPCs provides prognostic information in chronic HCV since it is significantly associated with stage of fibrosis. More importantly, it can be used as a marker to predict response of patients with chronic HCV to PEGIFN plus RBV therapy.Keywords: Chronic hepatitis C, genotype 4, response to therapy, hepatic progenitor cells

Surgical management of atrial myxoma and study of its inflammatory status: A single center study

Background: Cardiac myxomas are rare tumors mostly located in the left atrium, less often in right atrium and occasionally in all heart chambers. The aim of the present study is to report on the early outcomes and expression of inflammatory markers associated with the surgical treatment of myxoma patients between years 2018 up to 2023. Methods: The study included thirteen patients diagnosed with atrial myxoma. Five patients were retrospective cases under follow up and eight patients underwent prospective surgery. All patients were diagnosed by transthoracic echocardiography, then underwent median sternotomy for complete tumor resection. Left atrial myxoma was found in eleven cases while right atrial myxoma were found in two cases. Blood samples were obtained pre- and post-operatively from the eight prospective cases to determine the protein levels inflammatory markers IL-6 and TNF-α in addition to mRNA levels of IL-6. Results: Female patients represented 69.23% of total patients. Shortness of breath was involved in 61.53%, palpitation in 15.38% and atrial fibrillation in 15.38%. of patients. Mean tumor size was 3.75±1.6 cm. No recurrence or mortality were recorded and only one case of wound infection was found (7.69%). Biochemical results revealed significant increase (p<0.05) in IL-6 levels pre-operatively (99.25 ± 8.78 pg/mL) compared to post-operatively (41.13 ± 10.40 pg/mL). Moreover, IL-6 gene expression showed down-regulation in post-operative blood samples (p<0.05). In addition, TNF-α levels were significantly increased (p<0.05) pre-operatively (97.5 ± 16.34 pg/mL) compared to post-operatively (42.38 ± 8.03 pg/mL). Conclusion: Transthoracic echocardiography is the best diagnostic tool for myxoma diagnosis, median sternotomy with complete tumor resection decrease the rate of recurrence and mortality. Moreover, cardiac myxomas are associated with a distinct inflammatory state, evident by increased circulating inflammatory mediators as IL-6 and TNF-α which may act as markers in follow up to avoid recurrence

Modern eminence and concise critique of solar thermal energy and vacuum insulation technologies for sustainable low-carbon infrastructure

A concise critique on harnessing the abundant solar thermal energy and improvement with vacuum insulation for the utilization and conversion is presented. This research implicates that the world is becoming a global solar smart city prompted by increasing daily demand of energy by the global population and land-use. Amongst all the renewable energy resources available, solar thermal energy collectors (STC) are the most copious because it is accessible in both direct and indirect modes with global solar thermal capacity in operation in 2019 was 479 GWth and annual energy yield estimated to be 389 TWh. Hybridization has been found to be the only way of improving the existing performance of (STC) such as hybrid photovoltaic thermal (PVT) with phase-change material (PCM) for energy storage and magneto-thermoelectric generators (MTEGs) and/or vacuum insulated TEG (VTEG) for waste heat energy conversion to electrical power. The concentrating solar power (CSP) technologies were also precisely studied and yet parabolic trough collector, dish sterling and solar tower are amongst the top solar thermal heat energy harvesters and its electrical power generation has also been comprehended. The modern eminence of vacuum insulation technologies on thermal comfort and sound insulation in sustainable low-carbon buildings is presented. The research implicates that there is still a scope of improving the building and construction sector and target to achieve not only zero-energy buildings (ZEB) but generating-energy buildings (GEB). A concise critique on vacuum insulated smart glazed windows is presented and the review implicates that the hybridization with PV and TEG and novelty in the constructional materials of vacuum glazing (VG) and translucent vacuum insulation panel (TVIP) are vital in the realistic move towards the GEB. The future of vacuum insulation is not only limited to GEB but vital applications occur in medical, imaging, mechatronics and manufacturing industries

Population‐based cohort study of outcomes following cholecystectomy for benign gallbladder diseases

Background The aim was to describe the management of benign gallbladder disease and identify characteristics associated with all‐cause 30‐day readmissions and complications in a prospective population‐based cohort. Methods Data were collected on consecutive patients undergoing cholecystectomy in acute UK and Irish hospitals between 1 March and 1 May 2014. Potential explanatory variables influencing all‐cause 30‐day readmissions and complications were analysed by means of multilevel, multivariable logistic regression modelling using a two‐level hierarchical structure with patients (level 1) nested within hospitals (level 2). Results Data were collected on 8909 patients undergoing cholecystectomy from 167 hospitals. Some 1451 cholecystectomies (16·3 per cent) were performed as an emergency, 4165 (46·8 per cent) as elective operations, and 3293 patients (37·0 per cent) had had at least one previous emergency admission, but had surgery on a delayed basis. The readmission and complication rates at 30 days were 7·1 per cent (633 of 8909) and 10·8 per cent (962 of 8909) respectively. Both readmissions and complications were independently associated with increasing ASA fitness grade, duration of surgery, and increasing numbers of emergency admissions with gallbladder disease before cholecystectomy. No identifiable hospital characteristics were linked to readmissions and complications. Conclusion Readmissions and complications following cholecystectomy are common and associated with patient and disease characteristics

The role of hepatic progenitor cells in predicting response to therapy in Egyptian patients with chronic hepatitis C, genotype 4

Background: Interferon therapy is used as a line of treatment of chronic hepatitis C virus (HCV) in several areas of the world including Egypt. Objective: Our aim was to investigate the value of hepatic progenitor cells (HPCs) in predicting response of patients with chronic HCV, genotype 4 to pegylated interferon (PEGIFN) plus ribavirin (RBV) therapy. Methods: Pre-treatment liver biopsies obtained from 110 patients with chronic HCV, genotype 4 were examined immunohistochemically for HPCs using cytokeratin19. The mean number of HPCs as ductular reaction (DR) and as isolated progenitor cells (IPCs) was counted in each case. The patients were classified into: those with sustained virological response (SVR) and those who did not achieve SVR. The results were compared between the two groups. Also, the relationships between HPCs and other clinico-pathologic variables were estimated using multivariate analysis. Results: The mean number of HPCs was the only independent predictor of therapeutic response, being significantly higher in non-responders (P = 0 for DR and P = 0.03 for IPCs). On the other hand, fibrosis stage and steatosis were the only independent factors which showed a significant direct association with the mean number of HPCs in the form of DR and IPCs (P = 0 for each). Conclusion: The number of HPCs provides prognostic information in chronic HCV since it is significantly associated with stage of fibrosis. More importantly, it can be used as a marker to predict response of patients with chronic HCV to PEGIFN plus RBV therapy. DOI: https://dx.doi.org/10.4314/ahs.v19i1.14 Cite as: Helal T El A, Radwan NA, Mahmoud HA, Zaki AME, Ahmed NS, Wahib AAA, et al. The role of hepatic progenitor cells in predicting response to therapy in Egyptian patients with chronic hepatitis C, genotype 4. Afri Health Sci. 2019;19(1). 1411-1421. https://dx.doi.org/10.4314/ahs.v19i1.1

Knowledge and Perception Towards Psychotropic Drugs Among the General Population in Saudi Arabia

Eatedal M Al-Shareef,1 Alaa M Kadah Salim,1 Nada M Al-Farrah,1 Bader M Al-Murad,1 Adnan A Moallem,1 Mohammed A Radwan,1 Salman Hakami,2 Asim M Alshanberi,1,3 Mohammed Shaikhomer,4 Safaa M Alsanosi5 1General Medicine Program, Batterjee Medical College, Jeddah, 21442, Saudi Arabia; 2Department of Psychiatry, Mental Health Hospital, Ministry of Health, Jeddah, Saudi Arabia; 3Department of Community Medicine and Pilgrims Health Care, Faculty of Medicine, Umm Al Qura University, Makkah, Saudi Arabia; 4Department of Internal Medicine, Faculty of Medicine, King Abdulaziz University, Jeddah, Saudi Arabia; 5Department of Pharmacology and Toxicology Faculty of Medicine, Umm Al Qura University, Makkah, Saudi ArabiaCorrespondence: Safaa M Alsanosi, Email [email protected]: Mental health is crucial to overall well-being. Despite an increase in mental disorders over the past few decades, public awareness remains slow-growing, and stigmatization towards psychotropic medications persists. Therefore, this study aimed to identify knowledge and perceptions of psychotropic drugs among the general population in the Makkah Region, Saudi Arabia.Methods: A questionnaire-based cross-sectional study was conducted among adults aged 18 years old and older, living in the Makkah Region, Saudi Arabia, from 1 January to 30 April 2024. Descriptive statistics were used to describe participants’ characteristics, and categorical variables were reported as frequencies and percentages. A Chi-square test was used to examine the relationships between variables.Results: A total of 717 participants were involved in the study: (52%) were from Jeddah, (25.9%) were from Taif, and (22%) were from Makkah. The mean age was 33.9 years, and 67.1% were females. Among the participants, (20.8%) had experienced a psychiatric illness, (41.7%) had a member of the family who suffered from a psychiatric illness, (39.5%) had a family member who used a psychiatric drug, and only 25 (7%) had a child suffering from a psychiatric illness. Specifically, 20.8% of those with a psychiatric illness demonstrated good knowledge (P=0.001), 16.1% of those with a family history of psychiatric illness had good knowledge (P=0.007), 16.3% with family use of psychiatric drugs had good knowledge (P=0.006), and 24.5% of those who used psychiatric drugs had high knowledge (P=0.001). Overall, (40.6%) of participants had a low level of knowledge and perception about psychotropic drugs, (47.8%) had a moderate knowledge and perception level, and only (11.6%) had high knowledge and perception.Conclusion: Psychological well-being is crucial for health, but misconceptions persist, acting as barriers that impede people from seeking and accepting necessary psychiatric care. The findings highlight the need for targeted public education and healthcare professional training to improve Confirmed understanding and reduce stigma around psychotropic drugs in Saudi Arabia. A multifaceted approach involving policy development, community outreach, and ongoing research is essential for enhancing mental health outcomes and treatment accessibility.Keywords: knowledge, perception, psychotropic drugs, Saudi Arabi