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Fulltext Building Resilient communities: Techno-economic assessment of standalone off-grid PV powered net zero energy (NZE) villages

Arif S, Taweekun J, Ali HM, Ahmed A, Bhutto AA

Heliyon, 2023 Nov;9(11):e21426.
PMID: 38027710 DOI: 10.1016/j.heliyon.2023.e21426

The use of renewable energy resources for off-grid electricity production has gained more importance in recent decades for meeting the energy needs of remote areas, even with limited resources. This research aims to provide an optimized and cost-effective approach for generating electricity in rural areas. By using current methodology, a stand alone energy source of PV is designed for development of NZE village. Solar irradiance of the selected location is 6.16 kWh/m2/day while the estimated electric load data for whole village is 64.259 kWh. Electric load and solar irradiance of the loaction is used in the Hybrid Optimization Model for Electric Renewable (HOMER) to design and analyze the techno-economic feasibility of the stand alone PV system to meet the load requirements. The study obtained the total Net Present Cost (NPC) of $0.511 M and the Cost Of Electricity (COE) is 2.26$/unit through the HOMER analysis, which is further refined by performing sensitivity analysis using parameters such as PV panel price, battery price, solar irradiance, variations in electric load and discount rates. According to the results, system is feasibile by annual electricity production of 30,078 kWh with initial capital investment of $0.434 M. This analysis compared the system performance and showed that it is economically and technically viable to meet the complete electricity needs of the village with a payback period of 7.2 years. Research can be utilized for policy making and implementation of NZE approach in remote areas by the government.
Appraisal of latex glove proteins in the induction of sensitivity to multiple latex allergens

Yeang HY, Chow KS, Yusof F, Arif SA, Chew NP, Loke YH

J Investig Allergol Clin Immunol, 2000 Jul-Aug;10(4):215-22.
PMID: 11039838

Six Hevea brasiliensis latex protein allergens, Hevb 1, Hev b 2, Hev b 3, Hev b 4, and two variants of Hev b 7 (7b and 7c), were purified from Hevea latex, while a seventh protein, Hev b 5, was prepared in recombinant form. The presence of these proteins in glove extracts was indicated by their respective antibodies in the serum of rabbits immunized against the extracts. The relative propensities of IgE binding to the individual latex allergens were compared using sera from latex-allergic patients. IgE recognition of Hev b 4, Hev b 7b, Hev b 5 and Hev b 2 was most frequently encountered, with 75, 61, 31 and 28%, respectively, of the patient sera reacting. Sensitivity to multiple latex proteins was common, and out of the 31 seropositive patients, 23 (74%/ ) had IgE against at least two latex allergens, while 12 (39%) had IgE specific for at least three allergens. Statistical analysis of the data suggested that many patients might have acquired sensitivity to Hev b 2, Hev b 4 and Hev b 7b from a common source. (e.g., from latex products). On the other hand, sensitivity to Hev b 5 and to Hev b 7c were interrelated. It is plausible that sensitivity to these two proteins might have been acquired from sources other than latex products (e.g., from certain foods).
Molecular cloning and immunoglobulin E reactivity of a natural rubber latex lecithinase homologue, the major allergenic component of Hev b 4

Sunderasan E, Bahari A, Arif SA, Zainal Z, Hamilton RG, Yeang HY

Clin Exp Allergy, 2005 Nov;35(11):1490-5.
PMID: 16297147 DOI: 10.1111/j.1365-2222.2005.02371.x

BACKGROUND:
Hev b 4 is an allergenic natural rubber latex (NRL) protein complex that is reactive in skin prick tests and in vitro immunoassays. On SDS-polyacrylamide gel electrophoresis (SDS-PAGE), Hev b 4 is discerned predominantly at 53-55 kDa together with a 57 kDa minor component previously identified as a cyanogenic glucosidase. Of the 13 NRL allergens recognized by the International Union of Immunological Societies, the 53-55 kDa Hev b 4 major protein is the only candidate that lacks complete cDNA and protein sequence information.

OBJECTIVE:
We sought to clone the transcript encoding the Hev b 4 major protein, and characterize the native protein and its recombinant form in relation to IgE binding.

METHODS:
The 5'/3' rapid amplification of cDNA ends method was employed to obtain the complete cDNA of the Hev b 4 major protein. A recombinant form of the protein was over-expressed in Escherichia coli. The native Hev b 4 major protein was deglycosylated by trifluoromethane sulphonic acid. Western immunoblots of the native, deglycosylated and recombinant proteins were performed using both polyclonal antibodies and sera from latex-allergic patients.

RESULTS:
The cDNA encoding the Hev b 4 major protein was cloned. Its open reading frame matched lecithinases in the conserved domain database and contained 10 predicted glycosylation sites. Detection of glycans on the Hev b 4 lecithinase homologue confirmed it to be a glycoprotein. The deglycosylated lecithinase homologue was discerned at 40 kDa on SDS-PAGE, this being comparable to the 38.53 kDa mass predicted by its cDNA. Deglycosylation of the lecithinase homologue resulted in the loss of IgE recognition, although reactivity to polyclonal rabbit anti-Hev b 4 was retained. IgE from latex-allergic patients also failed to recognize the non-glycosylated E. coli recombinant lecithinase homologue.

CONCLUSION:
The IgE epitopes of the Hev b 4 lecithinase homologue reside mainly in its carbohydrate moiety, which also account for the discrepancy between the observed molecular weight of the protein and the value calculated from its cDNA.
Fulltext Adsorption and Kinetics Studies of Cr (VI) by Graphene Oxide and Reduced Graphene Oxide-Zinc Oxide Nanocomposite

Naseem T, Bibi F, Arif S, Waseem M, Haq S, Azra MN, et al.

Molecules, 2022 Oct 22;27(21).
PMID: 36363976 DOI: 10.3390/molecules27217152

In this work, graphene oxide (GO) and its reduced graphene oxide-zinc oxide nanocomposite (rGO-ZnO) was used for the removal of Cr (VI) from aqueous medium. By employing a variety of characterization techniques, morphological and structural properties of the adsorbents were determined. The adsorption study was done by varying concentration, temperature, pH, time, and amount of adsorbent. The results obtained confirmed that rGO-ZnO is a more economical and promising adsorbent for removing Cr (VI) as compared to GO. Kinetic study was also performed, which suggested that sorption of Cr (VI) follows the pseudo-first-order model. For equilibrium study, non-linear Langmuir was found a better fitted model than its linearized form. The maximum adsorption capacity calculated for GO and rGO-ZnO nanocomposite were 19.49 mg/g and 25.45 mg/g, respectively. Endothermic and spontaneous nature of adsorption was detected with positive values of ΔS (change in entropy), which reflects the structural changes happening at the liquid/solid interface.
Molecular docking studies of bioactive compounds from Annona muricata Linn as potential inhibitors for Bcl-2, Bcl-w and Mcl-1 antiapoptotic proteins

Mohamad Rosdi MN, Mohd Arif S, Abu Bakar MH, Razali SA, Mohamed Zulkifli R, Ya'akob H

Apoptosis, 2018 01;23(1):27-40.
PMID: 29204721 DOI: 10.1007/s10495-017-1434-7

Annona muricata Linn or usually identified as soursop is a potential anticancer plant that has been widely reported to contain valuable chemopreventive agents known as annonaceous acetogenins. The antiproliferative and anticancer activities of this tropical and subtropical plant have been demonstrated in cell culture and animal studies. A. muricata L. exerts inhibition against numerous types of cancer cells, involving multiple mechanism of actions such as apoptosis, a programmed cell death that are mainly regulated by Bcl-2 family of proteins. Nonetheless, the binding mode and the molecular interactions of the plant's bioactive constituents have not yet been unveiled for most of these mechanisms. In the current study, we aim to elucidate the binding interaction of ten bioactive phytochemicals of A. muricata L. to three Bcl-2 family of antiapoptotic proteins viz. Bcl-2, Bcl-w and Mcl-1 using an in silico molecular docking analysis software, Autodock 4.2. The stability of the complex with highest affinity was evaluated using MD simulation. We compared the docking analysis of these substances with pre-clinical Bcl-2 inhibitor namely obatoclax. The study identified the potential chemopreventive agent among the bioactive compounds. We also characterized the important interacting residues of protein targets which involve in the binding interaction. Results displayed that anonaine, a benzylisoquinoline alkaloid, showed a high affinity towards the Bcl-2, thus indicating that this compound is a potent inhibitor of the Bcl-2 antiapoptotic family of proteins.
Allergen concentration in natural rubber latex

Yeang HY, Hamilton RG, Bernstein DI, Arif SA, Chow KS, Loke YH, et al.

Clin Exp Allergy, 2006 Aug;36(8):1078-86.
PMID: 16911364 DOI: 10.1111/j.1365-2222.2006.02531.x

BACKGROUND:
Hevea brasiliensis latex serum is commonly used as the in vivo and in vitro reference antigen for latex allergy diagnosis as it contains the full complement of latex allergens.

OBJECTIVE:
This study quantifies the concentrations of the significant allergens in latex serum and examines its suitability as an antigen source in latex allergy diagnosis and immunotherapy.

METHODS:
The serum phase was extracted from centrifuged latex that was repeatedly freeze-thawed or glycerinated. Quantitation of latex allergens was performed by two-site immunoenzymetric assays. The abundance of RNA transcripts of the latex allergens was estimated from the number of their clones in an Expressed Sequence Tags library.

RESULTS:
The latex allergens, Hev b 1, 2, 3, 4, 5, 6, 7 and 13, were detected in freeze-thawed and glycerinated latex serum at levels ranging from 75 (Hev b 6) to 0.06 nmol/mg total proteins (Hev b 4). Hev b 6 content in the latex was up to a thousand times higher than the other seven latex allergens, depending on source and/or preparation procedure. Allergen concentration was reflected in the abundance of mRNA transcripts. When used as the antigen, latex serum may bias the outcome of latex allergy diagnostic tests towards sensitization to Hev b 6. Tests that make use of latex serum may fail to detect latex-specific IgE reactivity in subjects who are sensitized only to allergens that are present at low concentrations.

CONCLUSION:
Latex allergy diagnostics and immunotherapy that use whole latex serum as the antigen source may not be optimal because of the marked imbalance of its constituent allergens.
Fulltext How Are We Educating Future Physicians and Pharmacists in Pakistan? A Survey of the Medical and Pharmacy Student's Perception on Learning and Preparedness to Assume Future Roles in Antibiotic Use and Resistance

Mubarak N, Arif S, Irshad M, Aqeel RM, Khalid A, Ijaz UEB, et al.

Antibiotics (Basel), 2021 Oct 03;10(10).
PMID: 34680785 DOI: 10.3390/antibiotics10101204

BACKGROUND: Medical and pharmacy students are future healthcare professionals who will be on the forefront in dealing with antibiotics in hospitals or community settings. Whether the current medical and pharmacy education in Pakistan prepares students to take future roles in antibiotic use remains an under-researched area.
AIM: This study aims to compare medical and pharmacy students' perceived preparedness, learning practices and usefulness of the education and training on antibiotic use and resistance imparted during undergraduate studies in Pakistan.
DESIGN AND SETTING: It was amulti-centre cross-sectional survey of medical and pharmacy colleges in Punjab, Pakistan.
METHOD: A self-administered questionnaire was used to collect data from final year medical and pharmacy students. Descriptive statistics were used for categorical variables while independent t-test and One-way ANOVA computed group differences.
RESULT: Nine hundred forty-eight respondents (526 medical and 422 pharmacy students) completed the survey from 26 medical and 19 pharmacy colleges. Majority (76.1%) of the pharmacy students had not completed a clinical rotation in infectious diseases. The top three most often used sources of learning antibiotic use and resistance were the same among the medical and the pharmacy students; included textbooks, Wikipedia, and smart phone apps. Overall self-perceived preparedness scores showed no significant difference between pharmacy and medical students. The least prepared areas by medical and pharmacy students included transition from intravenous to oral antibiotics and interpretation of antibiograms. Both medical and pharmacy students found problem solving sessions attended by a small group of students to be the most useful (very useful) teaching methodology to learn antibiotic use and resistance.
CONCLUSIONS: Differences exist between medical and pharmacy students in educational resources used, topics covered during undergraduate degree. To curb the growing antibiotic misuse and resistance, the concerned authorities should undertake targeted educational reforms to ensure that future physicians and pharmacists can play a pivotal role in rationalizing the use of antibiotics.
Fulltext Pattern and associated factors of COVID-19 knowledge, attitude and practice (KAP) among COVID-19-comorbid patients: a systematic review and meta-analysis

Rehman AU, Tasleem Z, Muhammad SA, Rasool MF, Shah S, Jabeen G, et al.

Front Public Health, 2024;12:1365744.
PMID: 39494082 DOI: 10.3389/fpubh.2024.1365744

BACKGROUND: The COVID-19 comorbid population is at higher risk of developing severe health issues like acute respiratory distress syndrome, coagulation syndrome, metabolic acidosis, and septic shock, potentially leading to patient death. Patients' knowledge, attitudes, and practices (KAP) significantly influence their response to the pandemic and aid in enhancing health policy implementation.
OBJECTIVE: To identify and evaluate the pattern and associated factors to COVID-19 knowledge, attitude, and practice among individuals with comorbidities.
METHODOLOGY: The systematic review followed the PRISMA guidelines. Relevant studies assessing the KAP of comorbid patients were retrieved by carefully searching the PubMed and Google Scholar databases. The appraisal tool for cross-sectional studies was used to determine the quality of the included studies and the risk of biases.
RESULTS: Eighteen studies met the inclusion criteria and were included in the review. The pooled sample size of the included studies was 9,104. Different comorbidities reported in the studies include hypertension, diabetes, psychological disorders, and cancer. Pooled analysis showed that 65% of patients showed good knowledge, 57% of patients showed a positive attitude and 51% of patients followed good practices to manage the COVID-19 in presence of their comorbid condition. Significant factors impacting knowledge, attitude and practice in COVID-19 comorbid patients were ethnicity OR 1.78 [95% CI 1.35-2.32]; educational status 3.2 [2.79-3.58]; urban residence 2.43 [1.65-3.02]; employment Status 1.67[1.34-2.12]; financial Status 4.02[3.66-4.38]; occupation 3.65[3.31-4.25]; information Source 2.64[2.19-3.26]; comorbidity 3.28[2.78-3.61]; and duration of chronic illness 1.59[1.31-2.04].
CONCLUSION: Comorbid COVID-19 patients showed good knowledge, positive attitude and good practice towards the management of the disease.