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Nitrate and Nitrogen Oxides: Sources, Health Effects and Their Remediation

Hakeem KR, Sabir M, Ozturk M, Akhtar MS, Ibrahim FH

Rev Environ Contam Toxicol, 2017;242:183-217.
PMID: 27734212 DOI: 10.1007/398_2016_11

Increased use of nitrogenous (N) fertilizers in agriculture has significantly altered the global N-cycle because they release nitrogenous gases of environmental concerns. The emission of nitrous oxide (N2O) contributes to the global greenhouse gas accumulation and the stratospheric ozone depletion. In addition, it causes nitrate leaching problem deteriorating ground water quality. The nitrate toxicity has been reported in a number of studies showing the health hazards like methemoglobinemia in infants and is a potent cause of cancer. Despite these evident negative environmental as well as health impacts, consumption of N fertilizer cannot be reduced in view of the food security for the teeming growing world population. Various agronomic and genetic modifications have been practiced to tackle this problem. Some agronomic techniques adopted include split application of N, use of slow-release fertilizers, nitrification inhibitors and encouraging the use of organic manure over chemical fertilizers. As a matter of fact, the use of chemical means to remediate nitrate from the environment is very difficult and costly. Particularly, removal of nitrate from water is difficult task because it is chemically non-reactive in dilute aqueous solutions. Hence, the use of biological means for nitrate remediation offers a promising strategy to minimize the ill effects of nitrates and nitrites. One of the important goals to reduce N-fertilizer application can be effectively achieved by choosing N-efficient genotypes. This will ensure the optimum uptake of applied N in a balanced manner and exploring the molecular mechanisms for their uptake as well as metabolism in assimilatory pathways. The objectives of this paper are to evaluate the interrelations which exist in the terrestrial ecosystems between the plant type and characteristics of nutrient uptake and analyze the global consumption and demand for fertilizer nitrogen in relation to cereal production, evaluate the various methods used to determine nitrogen use efficincy (NUE), determine NUE for the major cereals grown across large agroclimatic regions, determine the key factors that control NUE, and finally analyze various strategies available to improve the use efficiency of fertilizer nitrogen.
Risk factors for high death and loss-to-follow-up rates among patients with multidrug-resistant tuberculosis at a programmatic management unit

Javaid A, Shaheen Z, Shafqat M, Khan AH, Ahmad N

Am J Infect Control, 2017 Feb 01;45(2):190-193.
PMID: 27769706 DOI: 10.1016/j.ajic.2016.07.026

Among 186 retrospectively evaluated patients with multidrug-resistant tuberculosis, 33.9% were cured, 6.6% completed treatment, 25% died, 18.3% were lost to follow-up, 2.2% failed treatment, and 13.8% were still undergoing treatment by the end of the study period. Rural residence was a risk factor for loss to follow-up (odds ratio [OR], 3.315; P = .016), whereas baseline body weight <40 kg (OR, 2.175; P = .042) and resistance to ofloxacin (OR, 2.889; P = .025) were risk factors for death. Despite programmatic management, treatment outcomes of the current cohort were distressing.
Fulltext Barriers and strategies to improve influenza vaccination in Pakistan

Farrukh MJ, Ming LC, Zaidi STR, Khan TM

J Infect Public Health, 2017 Nov-Dec;10(6):881-883.
PMID: 28185822 DOI: 10.1016/j.jiph.2016.11.021

Influenza vaccination is strongly recommended by World Health Organisation on a yearly basis. The rate of immunization in Pakistan is suboptimal. High cost, traditional norms, customs and low levels of education in Pakistan are preventing people from getting vaccinated. It is timely to include influenza vaccination in the expanded programme on immunization (EPI), which is a disease prevention programme aiming to eradicate preventable diseases through subsidized or free immunization. The Ministry of National Health Services, Regulation and Coordination, Government of Pakistan should launch a national influenza vaccine policy in view of this current situation and oversee its implementation. Healthcare professionals should promote influenza vaccination and focus on high risk groups such as the elderly, pregnant women and children. Convincing and educating family members regarding immunization of pregnant women and follow-up with parents regarding a second influenza shot for their children will further improve vaccination rates in Pakistan.
Fulltext Finite Element Analysis of Single Cell Stiffness Measurements Using PZT-Integrated Buckling Nanoneedles

Rad MA, Tijjani AS, Ahmad MR, Auwal SM

Sensors (Basel), 2016 Dec 23;17(1).
PMID: 28025571 DOI: 10.3390/s17010014

This paper proposes a new technique for real-time single cell stiffness measurement using lead zirconate titanate (PZT)-integrated buckling nanoneedles. The PZT and the buckling part of the nanoneedle have been modelled and validated using the ABAQUS software. The two parts are integrated together to function as a single unit. After calibration, the stiffness, Young's modulus, Poisson's ratio and sensitivity of the PZT-integrated buckling nanoneedle have been determined to be 0.7100 N·m-1, 123.4700 GPa, 0.3000 and 0.0693 V·m·N-1, respectively. Three Saccharomyces cerevisiae cells have been modelled and validated based on compression tests. The average global stiffness and Young's modulus of the cells are determined to be 10.8867 ± 0.0094 N·m-1 and 110.7033 ± 0.0081 MPa, respectively. The nanoneedle and the cell have been assembled to measure the local stiffness of the single Saccharomyces cerevisiae cells The local stiffness, Young's modulus and PZT output voltage of the three different size Saccharomyces cerevisiae have been determined at different environmental conditions. We investigated that, at low temperature the stiffness value is low to adapt to the change in the environmental condition. As a result, Saccharomyces cerevisiae becomes vulnerable to viral and bacterial attacks. Therefore, the proposed technique will serve as a quick and accurate process to diagnose diseases at early stage in a cell for effective treatment.
Could an automated machine replace the pharmacist?

Khan MU, Ahmad A, Malik S, Balkrishnan R

Res Social Adm Pharm, 2016 11 18;13(2):399.
PMID: 27884658 DOI: 10.1016/j.sapharm.2016.10.019
Fulltext Cadmium-109 Radioisotope Adsorption onto Polypyrrole Coated Sawdust of Dryobalanops aromatic: Kinetics and Adsorption Isotherms Modelling

Olatunji MA, Khandaker MU, Amin YM, Mahmud HN

PLoS One, 2016;11(10):e0164119.
PMID: 27706232 DOI: 10.1371/journal.pone.0164119

A radiotracer study was conducted to investigate the removal characteristics of cadmium (109Cd) from aqueous solution by polypyrrole/ sawdust composite. Several factors such as solution pH, sorbent dosage, initial concentration, contact time, temperature and interfering metal ions were found to have influence on the adsorption process. The kinetics of adsorption was relatively fast, reaching equilibrium within 3 hours. A lowering of the solution pH reduced the removal efficiency from 99.3 to ~ 46.7% and an ambient temperature of 25°C was found to be optimum for maximum adsorption. The presence of sodium and potassium ions inhibited 109Cd removal from its aqueous solution. The experimental data for 109Cd adsorption showed a very good agreement with the Langmuir isotherm and a pseudo-first order kinetic model. The surface condition of the adsorbent before and after cadmium loading was investigated using BET, FESEM and FTIR. Considering the low cost of the precursor's materials and the toxicity of 109Cd radioactive metal, polypyrrole synthesized on the sawdust of Dryobalanops aromatic could be used as an efficient adsorbent for the removal of 109Cd radioisotope from radionuclide-containing effluents.
Identification and future description of warming signatures over Pakistan with special emphasis on evolution of CO2 levels and temperature during the first decade of the twenty-first century

Haider K, Khokhar MF, Chishtie F, RazzaqKhan W, Hakeem KR

Environ Sci Pollut Res Int, 2017 Mar;24(8):7617-7629.
PMID: 28120226 DOI: 10.1007/s11356-016-8359-5

Like other developing countries, Pakistan is also facing changes in temperature per decade and other climatic abnormalities like droughts and torrential rains. In order to assess and identify the extent of temperature change over Pakistan, the whole Pakistan was divided into five climatic zones ranging from very cold to hot and dry climates. Similarly, seasons in Pakistan are defined on the basis of monsoon variability as winter, pre-monsoon, monsoon, and post-monsoon. This study primarily focuses on the comparison of surface temperature observations from Pakistan Meteorological Department (PMD) network with PRECIS (Providing Regional Climates for Impacts Studies) model simulations. Results indicate that PRECIS underestimates the temperature in Northern Pakistan and during the winter season. However, there exists a fair agreement between PRECIS output and observed datasets in the lower plain and hot areas of the country. An absolute increase of 0.07 °C is observed in the mean temperature over Pakistan during the time period of 1951-2010. Especially, the increase is more significant (0.7 °C) during the last 14 years (1997-2010). Moreover, SCIAMACHY observations were used to explore the evolution of atmospheric CO2 levels in comparison to temperature over Pakistan. CO2 levels have shown an increasing trend during the first decade of the twenty-first century.
Leptin and calorie intake among different nicotine dependent groups

Suhaimi MZ, Sanip Z, Jan HJ, Yusoff HM

Ann Saudi Med, 2016;36(6):404-408.
PMID: 27920412

BACKGROUND: Exposure to nicotine via tobacco smoking may influence leptin release and decrease food intake among smokers. However, the effect of nicotine exposure on leptin and food intake among different nicotine dependent groups is unclear.
OBJECTIVE: We aimed to measure leptin and calorie intake among different nicotine dependent groups.
DESIGN: Cross-sectional study.
SETTING: Research department in school of medical sciences.
PATIENTS AND METHODS: Subjects were selected by purposive (non-probability) sampling and categorized as having low, moderate and high nicotine dependency based on the Fagerstrom Test for Nicotine Dependence (FTND) score. Diet was recorded by interview. Anthropometry, blood pressure, body composition, lipid profile, and physical activity level were measured accordingly. Fasting serum leptin was measured using a commercial ELISA kit.
MAIN OUTCOME MEASURE(S): Nicotine dependency, 24-hour diet, clinical anthropometric and clinical measurements.
RESULTS: In 107 Malay male smokers leptin concentration was inversely correlated with nicotine dependence. However, body weight, smoking period, blood pressure, body composition, lipid profile and physical activity level were not significantly different among low, moderately and highly dependent smoking groups. Leptin concentration and total calorie intake were also not significantly different among these groups.
CONCLUSION: Leptin concentration was inversely correlated with nicotine dependence, but leptin concentration and total calorie intake status were not significantly different among our different nicotine dependency subjects.
LIMITATIONS: Purposive sampling for subject recruitment and inaccurate information in the self-administered questionnaire.
Source Determination of Red Gel Pen Inks using Raman Spectroscopy and Attenuated Total Reflectance Fourier Transform Infrared Spectroscopy combined with Pearson's Product Moment Correlation Coefficients and Principal Component Analysis

Mohamad Asri MN, Mat Desa WNS, Ismail D

J Forensic Sci, 2018 Jan;63(1):285-291.
PMID: 28480527 DOI: 10.1111/1556-4029.13522

The potential combination of two nondestructive techniques, that is, Raman spectroscopy (RS) and attenuated total reflectance-fourier transform infrared (ATR-FTIR) spectroscopy with Pearson's product moment correlation (PPMC) coefficient (r) and principal component analysis (PCA) to determine the actual source of red gel pen ink used to write a simulated threatening note, was examined. Eighteen (18) red gel pens purchased from Japan and Malaysia from November to December 2014 where one of the pens was used to write a simulated threatening note were analyzed using RS and ATR-FTIR spectroscopy, respectively. The spectra of all the red gel pen inks including the ink deposited on the simulated threatening note gathered from the RS and ATR-FTIR analyses were subjected to PPMC coefficient (r) calculation and principal component analysis (PCA). The coefficients r = 0.9985 and r = 0.9912 for pairwise combination of RS and ATR-FTIR spectra respectively and similarities in terms of PC1 and PC2 scores of one of the inks to the ink deposited on the simulated threatening note substantiated the feasibility of combining RS and ATR-FTIR spectroscopy with PPMC coefficient (r) and PCA for successful source determination of red gel pen inks. The development of pigment spectral library had allowed the ink deposited on the threatening note to be identified as XSL Poppy Red (CI Pigment Red 112).
Fulltext Extracellular Xylanopectinolytic Enzymes by Bacillus subtilis ADI1 from EFB's Compost

Nawawi MH, Mohamad R, Tahir PM, Saad WZ

Int Sch Res Notices, 2017;2017:7831954.
PMID: 28523288 DOI: 10.1155/2017/7831954

Microbial xylanase and pectinase are two extremely valuable enzymes, which have captivated much attention. This can be seen from the increased demand for these enzymes by many industrial sectors. This study investigates the isolation and screening of extracellular xylanopectinolytic enzymes-producing bacteria in a submerged fermentation (SmF). Samples are collected from the compost of empty fruit bunch (EFB) at Biocompost Pilot Plant, located at Biorefinery Plant, Universiti Putra Malaysia. From the experiment, out of 20 isolates, 11 isolates show xylanase or/and pectinase activity, and only one isolate (EFB-11) shows the concurrent activities of xylanase and pectinase. These activities are selected for enzyme production under submerged fermentation (quantitative screening). At the 72nd hour of incubation, xylanase and pectinase show the highest production, which ranges about 42.33 U/mL and 62.17 U/mL (with low amount of cellulase present), supplemented with 2% (w/v) of rice bran as carbon source at incubation temperature level, which is 30°C. Meanwhile, the pH of media is shifted to 8.42, which indicates that EFB-11 isolate is alkalotolerant bacteria and identified as Bacillus subtilis ADI1. This strain proves to have potential in agroindustrial bioconversion and has a promising ability to scale up to an industrial scale.
Fulltext The effect of inbreeding and larval feeding regime on immature development of Aedes albopictus

Jong ZW, Kassim NFA, Naziri MA, Webb CE

J Vector Ecol, 2017 06;42(1):105-112.
PMID: 28504428 DOI: 10.1111/jvec.12244

The fundamental approach to the biological control of Aedes albopictus requires the mass rearing of mosquitoes and the release of highly competitive adults in the field. As the fitness of adults is highly dependent on the development of immatures, we aimed to identify the minimum feeding regime required to produce viable and competitive adults by evaluating three response parameters: development duration, immature mortality, and adult wing length. Our study suggests at least 0.60 mg/larva/day of larval diet composed of dog food, dried beef liver, yeast, and milk powder in a weight ratio of 2:1:1:1 is required to maximize adult fitness. With standardized protocols in mass rearing, intensive studies can be readily conducted on mosquito colonies to facilitate comparisons across laboratories. This study also evaluated the differences in response of laboratory and field strains under different feeding regimes. We found that strain alone did not exert substantial effects on all response parameters. However, the field strain exhibited significantly lower immature mortality than the laboratory strain under the minimum feeding regime. Females and males of the laboratory strain had longer wing lengths under nutritional constraint due to the higher mortality that resulted in reduced interactions with the remaining larvae. Meanwhile, the field strain exhibited heterogeneous duration of immature development compared with the laboratory strain. The disparities demonstrated by the two strains in this study suggest the effect of inbreeding surfaced after a long term of laboratory colonization. Despite the trade-offs resulting from laboratory colonization, the competitiveness of the laboratory strain of Ae. albopictus is comparable to the field strain, provided the larvae are fed optimally.
Fulltext Transient Behavior in Variable Geometry Industrial Gas Turbines: A Comprehensive Overview of Pertinent Modeling Techniques

Hashmi MB, Lemma TA, Ahsan S, Rahman S

Entropy (Basel), 2021 Feb 22;23(2).
PMID: 33671488 DOI: 10.3390/e23020250

Generally, industrial gas turbines (IGT) face transient behavior during start-up, load change, shutdown and variations in ambient conditions. These transient conditions shift engine thermal equilibrium from one steady state to another steady state. In turn, various aero-thermal and mechanical stresses are developed that are adverse for engine's reliability, availability, and overall health. The transient behavior needs to be accurately predicted since it is highly related to low cycle fatigue and early failures, especially in the hot regions of the gas turbine. In the present paper, several critical aspects related to transient behavior and its modeling are reviewed and studied from the point of view of identifying potential research gaps within the context of fault detection and diagnostics (FDD) under dynamic conditions. Among the considered topics are, (i) general transient regimes and pertinent model formulation techniques, (ii) control mechanism for part-load operation, (iii) developing a database of variable geometry inlet guide vanes (VIGVs) and variable bleed valves (VBVs) schedules along with selection framework, and (iv) data compilation of shaft's polar moment of inertia for different types of engine's configurations. This comprehensive literature document, considering all the aspects of transient behavior and its associated modeling techniques will serve as an anchor point for the future researchers, gas turbine operators and design engineers for effective prognostics, FDD and predictive condition monitoring for variable geometry IGT.
Fulltext Experience of physicians during COVID-19 in a developing country: a qualitative study of Pakistan

Haq W, Said F, Batool S, Awais HM

J Infect Dev Ctries, 2021 03 07;15(2):191-197.
PMID: 33690199 DOI: 10.3855/jidc.13954

COVID-19 spread rapidly and jeopardised the physicians with not only treatment but also with limited resources and new working style. This study aimed to investigate the experience of physicians in Pakistan as frontline workers for the treatment of COVID-19 patients. The study employed a qualitative design and used Haas's adaptation of Colaizzi method for analysis. The respondents for the interview were selected based on purposive sampling and only those physicians were contacted who were treating COVID-19 patients in Lahore, Pakistan. The results of the study revealed many challenges faced by Pakistani physicians which included physical and psychological stress due to the treatment of COVID-19 patients. Moreover, infrastructural flaws have added in the vulnerabilities of the physicians. In developing countries, the fight is much harder for physicians as evidenced by their first-hand experience. The policymakers in developing countries especially in Pakistan can direct policies facilitating physicians to reduce their physical and psychological stress as well as increasing resources for the treatment of COVID-19 patients.
Fulltext Public Knowledge and Adherence to Hand Hygienic Guidelines for the Prevention of SARS-CoV-2 Transmission: A Cross-sectional Survey from Pakistan

Yaseen MO, Saif A, Khan TM, Yaseen M

Disaster Med Public Health Prep, 2022 Oct;16(5):1922-1928.
PMID: 33762050 DOI: 10.1017/dmp.2021.92

OBJECTIVE: Good hand hygienic practices are considered an important factor to curb the transmission and emergence of SARS-CoV -2. Various studies, conducted previously during the outbreaks of SARS-CoV and MERS-CoV, have ascertained the effectiveness of adopting good hand hygienic practices to curb the emergence of these viruses. This study aims to explore public hand hygienic practices during the peak pandemic period.
METHOD: A descriptive cross-sectional study was conducted among the general population of Pakistan to investigate the knowledge and perception about hand hygiene, self-reported hand hygiene practices, adherence to hand hygienic guidelines, and barriers to optimal hand hygiene. Kruskal-Wallis test, Mann-Whitney U test, and Regression model were used for statistical analysis.
RESULTS: There was a significant difference in area-based knowledge (P = 0.026), beliefs (P = 0.027), and practices (P = 0.002) regarding hand hygiene. The results of regression analysis revealed that people in urban areas were more likely to have better knowledge (β = 0.108, CI = 0.076 - 0.05, P = 0.008) and better adherence (β = 0.115, CI = 0.514 - 2.68, P = 0.004) to hand hygienic practices.
CONCLUSION: Advertisements on television and other electronic media with appealing slogans could be effective in making people more compliant to optimal hand hygienic practices.
In silico approach for Post-SELEX DNA aptamers: A mini-review

Ahmad NA, Mohamed Zulkifli R, Hussin H, Nadri MH

J Mol Graph Model, 2021 06;105:107872.
PMID: 33765525 DOI: 10.1016/j.jmgm.2021.107872

Aptamers are short oligonucleotides that possess high specificity and affinity against their target. Generated via Systematic Evolution of Ligands by Exponential Enrichment, (SELEX) in vitro, they were screened and enriched. This review covering the study utilizing bioinformatics tools to analyze primary sequence, secondary and tertiary structure prediction, as well as docking simulation for various aptamers and their ligand interaction. Literature was pooled from Web of Science (WoS) and Scopus databases until December 18, 2020 using specific search string related to DNA aptamers, in silico, structure prediction, and docking simulation. Out of 330 published articles, 38 articles were assessed in the analysis based on the predefined inclusion and exclusion criteria. It was found that Mfold and RNA Composer web server is the most popular tool in secondary and tertiary structure prediction of DNA aptamers, respectively. Meanwhile, in docking simulation, ZDOCK and AutoDock are preferred to analyze binding interaction in the aptamer-ligand complex. This review reports a brief framework of recent developments of in silico approaches that provide predictive structural information of ssDNA aptamer.
Fulltext Health System Governance for the Integration of Mental Health Services into Primary Health Care in the Sub-Saharan Africa and South Asia Region: A Systematic Review

Abd Rahim A, Abdul Manaf R, Juni MH, Ibrahim N

Inquiry, 2021 7 20;58:469580211028579.
PMID: 34275346 DOI: 10.1177/00469580211028579

Governance has been highlighted as an important building block underpinning the process of mental health integration into primary healthcare. This qualitative systematic review aims to identify the governance issues faced by countries in the Sub-Saharan Africa and South Asia Region in the implementation of integrated primary mental healthcare. PRISMA guideline was used to conduct a systematic search of relevant studies from 4 online databases that were filtered according to inclusion and exclusion criteria. Using the Critical Appraisal Skills Program (CASP) Qualitative Checklist, a quality appraisal of the selected articles was performed. By drawing upon institutional theory, data was extracted based on a pre-constructed matrix. The CERQual approach synthesized evidence and rank confidence level as low, moderate or high for 5 key findings. From 567 references identified, a total of 8 studies were included. Respondents were policymakers or implementers involved in integrated primary mental healthcare from the national, state, and district level. Overall, the main governance issues identified were a lack of leadership and mental health prioritization; inadequate financing and human resource capacity; and negative mental health perceptions/attitudes. The implication of the findings is that such issues must be addressed for long-term health system performance. This can also improve policymaking for better integration of primary mental health services into the health systems of countries in the Sub-Saharan and South Asia region.
Fulltext Metabolite Profiling of Malaysian Gracilaria edulis Reveals Eplerenone as Novel Antibacterial Compound for Drug Repurposing Against MDR Bacteria

Asghar A, Tan YC, Shahid M, Yow YY, Lahiri C

Front Microbiol, 2021;12:653562.
PMID: 34276590 DOI: 10.3389/fmicb.2021.653562

With a continuous threat of antimicrobial resistance on human health worldwide, efforts for new alternatives are ongoing for the management of bacterial infectious diseases. Natural products of land and sea, being conceived to be having fewer side effects, pose themselves as a welcome relief. In this respect, we have taken a scaffolded approach to unearthing the almost unexplored chemical constituents of Malaysian red seaweed, Gracilaria edulis. Essentially, a preliminary evaluation of the ethyl acetate and acetone solvent extracts, among a series of six such, revealed potential antibacterial activity against six MDR species namely, Klebsiella pneumoniae, Pseudomonas aeruginosa, Salmonella enterica, methicillin-resistant Staphylococcus aureus (MRSA), Streptococcus pyogenes, and Bacillus subtilis. Detailed analyses of the inlying chemical constituents, through LC-MS and GC-MS chromatographic separation, revealed a library of metabolic compounds. These were led for further virtual screening against selected key role playing proteins in the virulence of the aforesaid bacteria. To this end, detailed predictive pharmacological analyses added up to reinforce Eplerenone as a natural alternative from the plethora of plausible bioactives. Our work adds the ongoing effort to re-discover and repurpose biochemical compounds to combat the antimicrobial resistance offered by the Gram-positive and the -negative bacterial species.
Ficus deltoidea: Potential inhibitor of pro-inflammatory mediators in lipopolysaccharide-induced activation of microglial cells

Zolkiffly SZI, Stanslas J, Abdul Hamid H, Mehat MZ

J Ethnopharmacol, 2021 Oct 28;279:114309.
PMID: 34119609 DOI: 10.1016/j.jep.2021.114309

ETHNOPHARMACOLOGICAL RELEVANCE: Ficus deltoidea Jack (FD) is widely consumed in traditional medicine as a treatment for various diseases in Malaysia. Each part of the plant such as its leave, stem, fruit and root are used traditionally to treat different types of diseases. Vitexin and isovitexin are bioactive compounds abundantly found in the leaves of FD that possessed many pharmacological properties including neuroprotection. Nonetheless, its effects on key events in neuroinflammation are unknown.
AIM OF THE STUDY: To determine the inhibitory properties of FD aqueous extract on pro-inflammatory mediators involved in lipopolysaccharide (LPS)-induced microglial cells.
METHODS: Vitexin and isovitexin in the extract were quantified via high performance liquid chromatography (HPLC). The extract was evaluated for its cytotoxicity activity via 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Pre-treatment with the extract on LPS-induced microglial cells was done to determine its antioxidant and anti-neuroinflammatory properties by measuring the level of reactive oxygen species (ROS), nitric oxide (NO), tumour necrosis factor alpha (TNF-α), interleukin-1β (IL-1β) and interleukin-6 (IL-6) via 2'-7'-dichlorofluorescin diacetate (DCFDA) assay, Griess assay and Western blot respectively.
RESULTS: The extract at all tested concentrations (0.1 μg/mL, 1 μg/mL, 10 μg/mL, 100 μg/mL) were not cytotoxic as the percentage viability of microglial cells were all above ~80%. At the highest concentration (100 μg/mL), the extract significantly reduced the formation of ROS, NO, TNF-α, IL-1β and IL-6 in microglial cells induced by LPS.
CONCLUSION: The extract showed neuroprotective effects by attenuating the levels of pro-inflammatory and cytotoxic factors in LPS-induced microglial cells, possibly by mediating the nuclear factor-kappa B (NF-κB) signalling pathway.
Antiretrovirals shortage in Kenya amid COVID-19

Ullah I, Hassan W, Tahir MJ, Ahmed A

J Med Virol, 2021 Oct;93(10):5689-5690.
PMID: 34143897 DOI: 10.1002/jmv.27134
Fulltext Coatings in Decellularized Vascular Scaffolds for the Establishment of a Functional Endothelium: A Scoping Review of Vascular Graft Refinement

Heng JW, Yazid MD, Abdul Rahman MR, Sulaiman N

Front Cardiovasc Med, 2021;8:677588.
PMID: 34395554 DOI: 10.3389/fcvm.2021.677588

Developments in tissue engineering techniques have allowed for the creation of biocompatible, non-immunogenic alternative vascular grafts through the decellularization of existing tissues. With an ever-growing number of patients requiring life-saving vascular bypass grafting surgeries, the production of functional small diameter decellularized vascular scaffolds has never been more important. However, current implementations of small diameter decellularized vascular grafts face numerous clinical challenges attributed to premature graft failure as a consequence of common failure mechanisms such as acute thrombogenesis and intimal hyperplasia resulting from insufficient endothelial coverage on the graft lumen. This review summarizes some of the surface modifying coating agents currently used to improve the re-endothelialization efficiency and endothelial cell persistence in decellularized vascular scaffolds that could be applied in producing a better patency small diameter vascular graft. A comprehensive search yielding 192 publications was conducted in the PubMed, Scopus, Web of Science, and Ovid electronic databases. Careful screening and removal of unrelated publications and duplicate entries resulted in a total of 16 publications, which were discussed in this review. Selected publications demonstrate that the utilization of surface coating agents can induce endothelial cell adhesion, migration, and proliferation therefore leads to increased re-endothelialization efficiency. Unfortunately, the large variance in methodologies complicates comparison of coating effects between studies. Thus far, coating decellularized tissue gave encouraging results. These developments in re-endothelialization could be incorporated in the fabrication of functional, off-the-shelf alternative small diameter vascular scaffolds.

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