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Fulltext Prevalence and factors associated with secondhand smoke exposure among Malaysian adolescents

Ghazali SM, Huey TC, Cheong KC, Li LH, Fadhli M, Yusoff M, et al.

Tob Induc Dis, 2019;17:22.
PMID: 31582933 DOI: 10.18332/tid/102728

INTRODUCTION: Exposure to secondhand smoke (SHS) has been proven to be detrimental to health. However, there is little information on SHS exposure among Malaysian adolescents. This study aims to assess the magnitude of and factors associated with SHS exposure among school-going adolescents in Malaysia.
METHODS: We performed secondary analysis on data from 25461 respondents of the Global School Health Survey in Malaysia. Descriptive analyses and multivariable logistic regression were performed to determine factors associated with SHS exposure.
RESULTS: Respondents were adolescents of mean age 14.84 (SD=1.45) years, 50.2% of which were male and 49.8% female. Approximately four in ten respondents were exposed to SHS in the past week (41.5%). SHS exposure was significantly higher among respondents who smoked than among non-smokers (85.8% vs 35.7%, p<0.001). The likelihood of exposure to SHS was higher among smoking adolescents (Adjusted OR=1.66, 95% CI: 1.07-2.56) and non-smoking adolescents (AOR=3.15, 95% CI: 1.48-4.71) who had at least one smoking parent/guardian regardless of their own smoking status. Male adolescents had higher risk of SHS exposure compared to their female counterparts (current smoker AOR=1.66, 95% CI: 1.07-2.56; non-smoker AOR=1.50, 95% CI: 1.12-2.00) and increased with age, regardless of their smoking status.
CONCLUSIONS: Our findings suggest that prevalence of exposure to SHS among school-going adolescents in Malaysia is high. Parents should be advised to stop smoking or abstain from smoking in the presence of their children. Education programmes are recommended to increase awareness on avoidance of SHS as well as smoking cessation interventions for both adolescents and their parents.
Fulltext Different vascular healing process between bioabsorbable polymer-coated everolimus-eluting stents versus bioresorbable vascular scaffolds via optical coherence tomography and coronary angioscopy (the ENHANCE study: ENdothelial Healing Assessment with Novel Coronary tEchnology)

Wan Ahmad WA, Nakayoshi T, Mahmood Zuhdi AS, Ismail MD, Zainal Abidin I, Ino Y, et al.

Heart Vessels, 2020 Apr;35(4):463-473.
PMID: 31587103 DOI: 10.1007/s00380-019-01516-9

Recent clinical trials have raised concerns about the safety and efficacy of ABSORB™ bioresorbable vascular scaffolds (BVS). The difference in the vascular healing process between SYNERGY™ bioabsorbable polymer-coated everolimus-eluting stents (BP-EES) and BVS remains unclear. The aim of the ENHANCE study was to compare vascular healing on BP-EES versus BVS by optical coherence tomography (OCT) and coronary angioscopy (CAS) at 4- and 12-month follow-ups. This is a prospective, non-randomized, single center clinical trial. Thirteen eligible patients with multivessel disease were enrolled. BP-EES and BVS were simultaneously implanted in the same patients, but in different coronary vessels. Imaging follow-up with both OCT and CAS was completed in 11 patients at 12 months. Neointimal coverage rates were similar between the two groups based on OCT measurements. The neointimal thickness of BP-EES was significantly thicker at the 12th month than at the 4th month, whereas the neointimal thickness of BVS did not change between the measurements taken at the 4th and 12th month. Existence of intra-stent thrombus was significantly higher in the BVS group, compared to the BP-EES group. On the other hand, CAS revealed that red-thrombi and yellow-plaque were more frequently observed in BVS at 4 months and up to 12-month follow-ups than in BP-EES. These findings suggested that the evidence of instability remained up to 12 months in the vascular healing with BVS, compared to that with BP-EES. Vascular healing of the stented wall was recognized at the very early phase after BP-EES implantation. However, vascular healing with BVS was still incomplete after 12 months.
Characterization and expression in Pichia pastoris of a raw starch degrading glucoamylase (GA2) derived from Aspergillus flavus NSH9

Karim KMR, Husaini A, Sing NN, Tasnim T, Mohd Sinang F, Hussain H, et al.

Protein Expr Purif, 2019 12;164:105462.
PMID: 31351992 DOI: 10.1016/j.pep.2019.105462

The Aspergillus flavus NSH9 gene, encoding a pH and thermostable glucoamylase with a starch binding domain (SBD), was expressed in Pichia pastoris to produce recombinant glucoamylase (rGA2). The full-length glucoamylase gene (2039 bp), and cDNA (1839 bp) encode a 612 amino acid protein most similar to glucoamylase from Aspergillus oryzae RIB40; the first 19 amino acids are presumed to be a signal peptide for secretion, and the SBD is at the C-terminal. The cDNA was successfully secreted by Pichia at 8.23 U mL-1, and the rGA2 was found to be: a 80 kDa monomer, stable from pH 3.0-9.0, with optimum catalytic activity at pH 5.0, active at temperatures up to 80°C (rGA2 retained 58% of its activity after 60 min of incubation at 70°C), and metal ions such as Na+, K+, Ca++ and Mg++ enhanced rGA2 enzyme activity. The starch degrading ability of rGA2 was also observed on raw sago starch and where prolonged incubation generated larger, deeper, holes on the starch granules, indicating rGA2 is an excellent candidate for industrial starch processing applications.
Fulltext Contribution of Genetic Polymorphisms of Inflammation Response Genes on Sporadic Colorectal Cancer Predisposition Risk in Malaysian Patients - A Case Control Study

Ankathil R, Mustapha MA, Abdul Aziz AA, Mohd Shahpudin SN, Zakaria AD, Abu Hassan MR, et al.

Asian Pac J Cancer Prev, 2019 06 01;20(6):1621-1632.
PMID: 31244280 DOI: 10.31557/APJCP.2019.20.6.1621

AIM: To investigate the frequencies and association of polymorphic genotypes of IL-8 -251 T>A, TNF-α -308
G>A, ICAM-1 K469E, ICAM-1 R241G, IL-6 -174 G>C, and PPAR-γ 34 C>G in modulating susceptibility risk in
Malaysian colorectal cancer (CRC) patients. Methods: In this case-control study, peripheral blood samples of 560
study subjects (280 CRC patients and 280 controls) were collected, DNA extracted and genotyped using PCR-RFLP
and Allele Specific PCR. The association between polymorphic genotype and CRC susceptibility risk was determined
using Logistic Regression analysis deriving Odds ratio (OR) and 95% CI. Results: On comparing the frequencies of
genotypes of all single nucleotide polymorphisms ( SNPs ) in patients and controls, the homozygous variant genotypes
IL-8 -251 AA and TNF-α -308 AA and variant A alleles were significantly higher in CRC patients. Investigation on
the association of the variant alleles and genotypes singly, with susceptibility risk showed the homozygous variant A
alleles and genotypes IL-8 -251 AA and TNF-α -308 AA to be at higher risk for CRC predisposition. Analysis based
on age, gender and smoking habits showed that the polymorphisms IL8 -251 T>A and TNF – α 308 G>A contribute
to a significantly higher risk among male and female who are more than 50 years and for smokers in this population.
Conclusion: We observed an association between variant allele and genotypes of IL-8-251 T>A and TNF-α-308
G>A polymorphisms and CRC susceptibility risk in Malaysian patients. These two SNPs in inflammatory response
genes which undoubtedly contribute to individual risks to CRC susceptibility may be considered as potential genetic
predisposition factors for CRC in Malaysian population.
Fulltext Detection of dengue using PAMAM dendrimer integrated tapered optical fiber sensor

Mustapha Kamil Y, Al-Rekabi SH, Yaacob MH, Syahir A, Chee HY, Mahdi MA, et al.

Sci Rep, 2019 09 17;9(1):13483.
PMID: 31530893 DOI: 10.1038/s41598-019-49891-7

The exponential escalation of dengue cases has indeed become a global health crisis. This work elaborates on the development of a biofunctionalized tapered optical fiber (TOF) based sensor with the integration of polyamidoamine (PAMAM) dendrimer for the detection of dengue E protein. The dimension of the TOF generated an evanescent field that was sensitive to any changes in the external medium while the integration of PAMAM promoted more adhesion of bio-recognition molecules; anti-DENV II E protein antibodies; that were complementary to the targeted protein. This in return created more active sites for the absorption of DENV II E proteins onto the tapered region. The resolution and detection limit of the sensor are 19.53 nm/nM and 1 pM, respectively with Kd = 1.02 × 10-10 M.
Synthesis of benzotriazoles derivatives and their dual potential as α-amylase and α-glucosidase inhibitors in vitro: Structure-activity relationship, molecular docking, and kinetic studies

Hameed S, Kanwal, Seraj F, Rafique R, Chigurupati S, Wadood A, et al.

Eur J Med Chem, 2019 Dec 01;183:111677.
PMID: 31514061 DOI: 10.1016/j.ejmech.2019.111677

Benzotriazoles (4-6) were synthesized which were further reacted with different substituted benzoic acids and phenacyl bromides to synthesize benzotriazole derivatives (7-40). The synthetic compounds (7-40) were characterized via different spectroscopic techniques including EI-MS, HREI-MS, 1H-, and 13C NMR. These molecules were examined for their anti-hyperglycemic potential hence were evaluated for α-glucosidase and α-amylase inhibitory activities. All benzotriazoles displayed moderate to good inhibitory activity in the range of IC50 values of 2.00-5.6 and 2.04-5.72 μM against α-glucosidase and α-amylase enzymes, respectively. The synthetic compounds were divided into two categories "A" and "B", in order to understand the structure-activity relationship. Compounds 25 (IC50 = 2.41 ± 1.31 μM), (IC50 = 2.5 ± 1.21 μM), 36 (IC50 = 2.12 ± 1.35 μM), (IC50 = 2.21 ± 1.08 μM), and 37 (IC50 = 2.00 ± 1.22 μM), (IC50 = 2.04 ± 1.4 μM) with chloro substitution/s at aryl ring were found to be most active against α-glucosidase and α-amylase enzymes. Molecular docking studies on all compounds were performed which revealed that chloro substitutions are playing a pivotal role in the binding interactions. The enzyme inhibition mode was also studied and the kinetic studies revealed that the synthetic molecules have shown competitive mode of inhibition against α-amylase and non-competitive mode of inhibition against α-glucosidase enzyme.
Partial remission in type 1 diabetes and associated factors: Analysis based on the insulin dose-adjusted hemoglobin A1c in children and adolescents from a regional diabetes center, Auckland, New Zealand

Chiavaroli V, Derraik JGB, Jalaludin MY, Albert BB, Ramkumar S, Cutfield WS, et al.

Pediatr Diabetes, 2019 11;20(7):892-900.
PMID: 31237756 DOI: 10.1111/pedi.12881

BACKGROUND: Partial remission (PREM) by the insulin dose-adjusted HbA1c (IDAA1c) method has not been evaluated for the combined associations of ethnicity and socioeconomic status in children and adolescents with type 1 diabetes (T1D).
OBJECTIVE: To investigate prevalence and predictors of PREM defined by IDAA1c.
METHODS: Six hundred fourteen of 678 children (aged <15 years) with new-onset T1D (2000-2013) from a regional pediatric diabetes service (Auckland, New Zealand).
RESULTS: Overall rate of PREM at 3 months was 42.4%, and lower in Māori/Pacific children (28.6%; P = .006) and those of other ethnicities (28.8%; P = .030) compared with New Zealand Europeans (50.4%). Comparing the most and least deprived socioeconomic quintiles, the odds of PREM were lower among the most deprived (adjusted odds ratio [aOR] 0.44; P = .019). Lower rates of PREM were seen in children aged 0 to 4.9 years (23.8%) and 10 to 14 years (40.9%) than in children aged 5 to 9.9 years (57.4%; P
Methodology and Representativeness of the Adolescent Health Survey 2017 in Malaysia

Awaluddin SM, Ibrahim Wong N, Rodzlan Hasani WS, Omar MA, Mohd Yusoff MF, Nik Abd Rashid NR, et al.

Asia Pac J Public Health, 2019 11;31(8_suppl):8S-17S.
PMID: 31226891 DOI: 10.1177/1010539519854884

Health risk behaviors and mental health problems are associated with morbidity and premature mortality among adolescents. Understanding the magnitude of the problem may improve adolescent health status. The Adolescent Health Survey was conducted to collect data on health risk behaviors among Malaysian school-going adolescents using self-administered questionnaires. A 2-stage stratified cluster sampling design was used and samplings weights were calculated to ensure representativeness to the general population. A total of 27 497 out of 30 823 school-going adolescents completed the questionnaires, yielded an 89.2% overall response rate. The methodology was robust to ensure valid estimation on the prevalence of health problems among Malaysian school-going adolescents.
Synthesis of new indazole based dual inhibitors of α-glucosidase and α-amylase enzymes, their in vitro, in silico and kinetics studies

Rafique R, Khan KM, Arshia, Kanwal, Chigurupati S, Wadood A, et al.

Bioorg Chem, 2020 01;94:103195.
PMID: 31451297 DOI: 10.1016/j.bioorg.2019.103195

The current study describes the discovery of novel inhibitors of α-glucosidase and α-amylase enzymes. For that purpose, new hybrid analogs of N-hydrazinecarbothioamide substituted indazoles 4-18 were synthesized and fully characterized by EI-MS, FAB-MS, HRFAB-MS, 1H-, and 13C NMR spectroscopic techniques. Stereochemistry of the imine double bond was established by NOESY measurements. All derivatives 4-18 with their intermediates 1-3, were evaluated for in vitro α-glucosidase and α-amylase enzyme inhibition. It is worth mentioning that all synthetic compounds showed good inhibition potential in the range of 1.54 ± 0.02-4.89 ± 0.02 µM for α-glucosidase and for α-amylase 1.42 ± 0.04-4.5 ± 0.18 µM in comparison with the standard acarbose (IC50 value of 1.36 ± 0.01 µM). In silico studies were carried out to rationalize the mode of binding interaction of ligands with the active site of enzymes. Moreover, enzyme inhibitory kinetic characterization was also performed to understand the mechanism of enzyme inhibition.
Fulltext Awareness on breast cancer screening in Malaysia: a cross sectional study

Lee MS, 'Azmiyaty Amar Ma' Ruf C, Nadhirah Izhar DP, Nafisah Ishak S, Wan Jamaluddin WS, Ya'acob SNM, et al.

Biomedicine (Taipei), 2019 Sep;9(3):18.
PMID: 31453799 DOI: 10.1051/bmdcn/2019090318

INTRODUCTION: The increasing rate of breast cancer (BC) incidence in Malaysia hints a lack of awareness among Malaysians. One (1) woman out of nineteen (19) is at risk with BC and almost up to fifty percent (50%) of women diagnosed with BC were reported to be under the age of fifty (50). Our main concern is to study the level of awareness among the women on risk factors, clinical manifestations, diagnosis, preventions and treatments.
METHOD: A cross-sectional study was conducted exclusively among women in the public with total sample of three hundred and forty six (346), questionnaires were distributed using a simple random technique. Data was collected and analyzed by student T test in SPPS version 20.
RESULTS: Our study reveals insufficient awareness on BC. Overall, awareness on risk factors is inadequate, but good knowledge on the importance of family history and diet as risk factors are discovered. Awareness on the cause and clinical manifestations of BC is required for improvement. As for treatment, alternatives especially surgery and chemotherapy are unclear to public, public is remotely unwitting on cessation of smoking to prevent BC at the early stage.
CONCLUSION: Malaysian has spaces for improvement on awareness of BC in terms of risk factors, clinical manifestations, diagnosis, treatment and prevention. Early detection can be achieved with good awareness because it leads to better prognosis and lower mortality.
Thermo-catalytic decomposition of polystyrene waste: Comparative analysis using different kinetic models

Ali G, Nisar J, Iqbal M, Shah A, Abbas M, Shah MR, et al.

Waste Manag Res, 2019 Aug 13.
PMID: 31405341 DOI: 10.1177/0734242X19865339

Due to a huge increase in polymer production, a tremendous increase in municipal solid waste is observed. Every year the existing landfills for disposal of waste polymers decrease and the effective recycling techniques for waste polymers are getting more and more important. In this work pyrolysis of waste polystyrene was performed in the presence of a laboratory synthesized copper oxide. The samples were pyrolyzed at different heating rates that is, 5°Cmin-1, 10°Cmin-1, 15°Cmin-1 and 20°Cmin-1 in a thermogravimetric analyzer in inert atmosphere using nitrogen. Thermogravimetric data were interpreted using various model fitting (Coats-Redfern) and model free methods (Ozawa-Flynn-Wall, Kissinger-Akahira-Sunose and Friedman). Thermodynamic parameters for the reaction were also determined. The activation energy calculated applying Coats-Redfern, Ozawa-Flynn-Wall, Kissinger-Akahira-Sunose and Friedman models were found in the ranges 105-148.48 kJmol-1, 99.41-140.52 kJmol-1, 103.67-149.15 kJmol-1 and 99.93-141.25 kJmol-1, respectively. The lowest activation energy for polystyrene degradation in the presence of copper oxide indicates the suitability of catalyst for the decomposition reaction to take place at lower temperature. Moreover, the obtained kinetics and thermodynamic parameters would be very helpful in determining the reaction mechanism of the solid waste in a real system.
Synthesis of oxadiazole-coupled-thiadiazole derivatives as a potent β-glucuronidase inhibitors and their molecular docking study

Taha M, Imran S, Alomari M, Rahim F, Wadood A, Mosaddik A, et al.

Bioorg Med Chem, 2019 07 15;27(14):3145-3155.
PMID: 31196753 DOI: 10.1016/j.bmc.2019.05.049

A new series of oxadiazole with thiadiazole moiety (6-27) were synthesized, characterized by different spectroscopic techniques and evaluated for β-glucuronidase inhibitory potential. Sixteen analogs such as 6, 7, 8, 9, 10, 12, 13, 14, 17, 18, 20, 23, 24, 25, 26 and 27 showed IC50 values in the range of 0.96 ± 0.01 to 46.46 ± 1.10 μM, and hence were found to have excellent inhibitory potential in comparison to standard d-saccharic acid 1,4-lactone (IC50 = 48.4 ± 1.25 μM). Two analogs such as 16 and 19 showed moderate inhibitory potential while analogs 11, 15, 21 and 22 were found inactive. Our study identifies new series of potent β-glucuronidase inhibitors for further investigation. Structure activity relationships were established for all compounds which showed that the activity is varied due to different substituents on benzene ring. The interaction of the compounds with enzyme active site were confirmed with the help of docking studies, which reveals that the electron withdrawing group and hydroxy group make the molecules more favorable for enzyme inhibition.
Fulltext Improving Performance of Electrospun Nylon 6,6 Nanofiber Membrane for Produced Water Filtration via Solvent Vapor Treatment

Abd Halim NS, Wirzal MDH, Bilad MR, Md Nordin NAH, Adi Putra Z, Sambudi NS, et al.

Polymers (Basel), 2019 Dec 17;11(12).
PMID: 31861059 DOI: 10.3390/polym11122117

Electrospun nanofiber membrane (NFM) has a high potential to be applied as a filter for produced water treatment due to its highly porous structure and great permeability. However, it faces fouling issues and has low mechanical properties, which reduces the performance and lifespan of the membrane. NFM has a low integrity and the fine mat easily detaches from the sheet. In this study, nylon 6,6 was selected as the polymer since it offers great hydrophilicity. In order to increase mechanical strength and separation performance of NFM, solvent vapor treatment was implemented where the vapor induces the fusion of fibers. The fabricated nylon 6,6 NFMs were treated with different exposure times of formic acid vapor. Results show that solvent vapor treatment helps to induce the fusion of overlapping fibers. The optimum exposure time for solvent vapor is 5 h to offer full retention of dispersed oil (100% of oil rejection), has 62% higher in tensile strength (1950 MPa) compared to untreated nylon 6,6 NFM (738 MPa), and has the final permeability closest to the untreated nylon 6,6 NFM (733 L/m2.h.bar). It also took more time to get fouled (220 min) compared to untreated NFM (160 min).
Functional and structural analyses of an expansin-like protein from the antarctic yeast Glaciozyma antarctica PI12 reveal strategies of nutrient scavenging in the sea ice environment

Mohamad Nor N, Hashim NHF, Quay DHX, Mahadi NM, Illias RM, Abu Bakar FD, et al.

Int J Biol Macromol, 2020 Feb 01;144:231-241.
PMID: 31843615 DOI: 10.1016/j.ijbiomac.2019.12.099

Genome data mining of the Antarctic yeast, Glaciozyma antarctica PI12 revealed an expansin-like protein encoding sequence (GaEXLX1). The GaEXLX1 protein is 24.8 kDa with a high alkaline pI of 9.81. Homology modeling of GaEXLX1 showed complete D1 and D2 domains of a conventional expansin. The protein exhibited 36% sequence similarity to Clavibacter michiganensis EXLX1 (PDB: 4JCW). Subsequently, a recombinant GaEXLX1 protein was produced using Escherichia coli expression system. Incubation with Avicel, filter paper and cotton fiber showed that the protein can disrupt the surface of crystalline and pure cellulose, suggesting a cell wall modification activity usually exhibited by expansin-like proteins. Binding assays displayed that GaEXLX1 can bind to polymeric substrates, including those postulated to be present in the sea ice ecosystem such as crab chitin and moss lichenan. GaEXLX1 may assist in the recognition and loosening of these substrates in the sea ice prior to hydrolysis by other extracellular enzymes. Similar loosening mechanism to classical expansin-like protein has been postulated for this psychrophilic protein based on several conserved residues of GaEXLX1 involved in binding interaction identified by docking analyses.
Fulltext Amino Anthraquinone: Synthesis, Characterization, and Its Application as an Active Material in Environmental Sensors

Ali S, Tahir M, Mehboob N, Wahab F, J Langford S, Mohd Said S, et al.

Materials (Basel), 2020 Feb 21;13(4).
PMID: 32098037 DOI: 10.3390/ma13040960

This work reports synthesis, thin film characterizations, and study of an organic semiconductor 2-aminoanthraquinone (AAq) for humidity and temperature sensing applications. The morphological and phase studies of AAq thin films are carried out by scanning electron microscope (SEM), atomic force microscope (AFM), and X-ray diffraction (XRD) analysis. To study the sensing properties of AAq, a surface type Au/AAq/Au sensor is fabricated by thermally depositing a 60 nm layer of AAq at a pressure of ~10-5 mbar on a pre-patterned gold (Au) electrodes with inter-electrode gap of 45 µm. To measure sensing capability of the Au/AAq/Au device, the variations in its capacitance and resistance are studied as a function of humidity and temperature. The Au/AAq/Au device measures and exhibits a linear change in capacitance and resistance when relative humidity (%RH) and temperature are varied. The AAq is a hydrophobic material which makes it one of the best candidates to be used as an active material in humidity sensors; on the other hand, its high melting point (575 K) is another appealing property that enables it for its potential applications in temperature sensors.
Fulltext Reverse vaccinology approach for the identification and characterization of outer membrane proteins of Shigella flexneri as potential cellular- and antibody-dependent vaccine candidates

Leow CY, Kazi A, Hisyam Ismail CMK, Chuah C, Lim BH, Leow CH, et al.

Clin Exp Vaccine Res, 2020 Jan;9(1):15-25.
PMID: 32095437 DOI: 10.7774/cevr.2020.9.1.15

Purpose: In the developing world, bacillary dysentery is one of the most common communicable diarrheal infections. There are approximately 169 million cases of shigellosis reported worldwide. The disease is transmitted by a group of Gram-negative intracellular enterobacteria known as Shigella flexneri, S. sonnei, S. dysenteriae, and S. boydii. Conventional treatment regimens for Shigella have been less effective due to the development of resistant strains against antibiotics. Therefore, an effective vaccine for the long term control of Shigella transmission is urgently needed.
Materials and Methods: In this study, a reverse vaccinology approach was employed to identify most conserved and immunogenic outer membrane proteins (OMPs) of S. flexneri 2a.
Results: Five OMPs including fepA, ompC, nlpD_1, tolC, and nlpD_2 were identified as potential vaccine candidates. Protein-protein interactions analysis using STRING software (https://string-db.org/) revealed that five of these OMPs may potentially interact with other intracellular proteins which are involved in beta-lactam resistance pathway. B- and T-cell epitopes of the selected OMPs were predicted using BCPred as well as Propred I and Propred (http://crdd.osdd.net/raghava/propred/), respectively. Each of these OMPs contains regions which are capable to induce B- and T-cell immune responses.
Conclusion: Analysis acquired from this study showed that five selected OMPs have great potential for vaccine development against S. flexneri infection. The predicted immunogenic epitopes can also be used for development of peptide vaccines or multi-epitope vaccines against human shigellosis. Reverse vaccinology is a promising strategy for the discovery of potential vaccine candidates which can be used for future vaccine development against global persistent infections.
Fulltext Patterned Membrane in an Energy-Efficient Tilted Panel Filtration System for Fouling Control in Activated Sludge Filtration

Osman A, Mat Nawi NI, Samsuri S, Bilad MR, Shamsuddin N, Khan AL, et al.

Polymers (Basel), 2020 Feb 12;12(2).
PMID: 32059397 DOI: 10.3390/polym12020432

A membrane bioreactor enhances the overall biological performance of a conventional activated sludge system for wastewater treatment by producing high-quality effluent suitable for reuse. However, membrane fouling hinders the widespread application of membrane bioreactors by reducing the hydraulic performance, shortening membrane lifespan, and increasing the operational costs for membrane fouling management. This study assesses the combined effect of membrane surface corrugation and a tilted panel in enhancing the impact of air bubbling for membrane fouling control in activated sludge filtration, applicable for membrane bioreactors. The filterability performance of such a system was further tested under variable parameters: Filtration cycle, aeration rate, and intermittent aeration. Results show that a combination of surface corrugation and panel tilting enhances the impact of aeration and leads to 87% permeance increment. The results of the parametric study shows that the highest permeance was achieved under short filtration-relaxation cycle of 5 min, high aeration rate of 1.5 L/min, and short switching period of 2.5 min, to yield the permeances of 465 ± 18, 447 ± 2, and 369 ± 9 L/(m2h bar), respectively. The high permeances lead to higher operational flux that helps to lower the membrane area as well as energy consumption. Initial estimation of the fully aerated system yields the energy input of 0.152 kWh/m3, much lower than data from the full-scale references of <0.4 kWh/m3. Further energy savings and a lower system footprint can still be achieved by applying the two-sided panel with a switching system, which will be addressed in the future.
Effect of gasotransmitters treatment on expression of hypertension, vascular and cardiac remodeling and hypertensive nephropathy genes in left ventricular hypertrophy

Ahmad A, Riaz Z, Sattar MA, Khan SA, John EJ, Rashid S, et al.

Gene, 2020 May 05;737:144479.
PMID: 32068124 DOI: 10.1016/j.gene.2020.144479

BACKGROUND: Cardiac and renal dysfunction are often co-morbid pathologies leading to worsening prognosis resulting in difficulty in therapy of left ventricular hypertrophy (LVH). The aim of the current study was to determine the changes in expression of human ortholog genes of hypertension, vascular and cardiac remodeling and hypertensive nephropathy phenotypes under normal, disease and upon treatment with gasotransmitter including H2S (hydrogen sulphide), NO (nitric oxide) and combined (H2S + NO).
METHODS: A total of 72 Wistar Kyoto rats (with equivalent male and female animals) were recruited in the present study where LVH rat models were treated with H2S and NO individually as well as with both combined. Cardiac and renal physical indices were recorded and relative gene expression were quantified.
RESULTS: Both cardiac and renal physical indices were significantly modified with individual as well as combined H2S + NO treatment in control and LVH rats. Expression analysis revealed, hypertension, vascular remodeling genes ACE, TNFα and IGF1, mRNAs to be significantly higher (P ≤ 0.05) in the myocardia and renal tissues of LVH rats, while individual and combined H2S + NO treatment resulted in lowering the gene expression to normal/near to normal levels. The cardiac remodeling genes MYH7, TGFβ, SMAD4 and BRG1 expression were significantly up-regulated (P ≤ 0.05) in the myocardia of LVH where the combined H2S + NO treatment resulted in normal/near to normal expression more effectively as compared to individual treatments. In addition individual as well as combined H2S and NO treatment significantly decreased PKD1 expression in renal tissue, which was up-regulated in LVH rats (P ≤ 0.05).
CONCLUSIONS: The reduction in hemodynamic parameters and cardiac indices as well as alteration in gene expression on treatment of LVH rat model indicates important therapeutic potential of combined treatment with H2S + NO gasotransmitters in hypertension and cardiac hypertrophy when present as co-morbidity with renal complications.
Fulltext A Systematic Approach to the Design and Characterization of A Smart Insole for Detecting Vertical Ground Reaction Force (vGRF) in Gait Analysis

Tahir AM, Chowdhury MEH, Khandakar A, Al-Hamouz S, Abdalla M, Awadallah S, et al.

Sensors (Basel), 2020 Feb 11;20(4).
PMID: 32053914 DOI: 10.3390/s20040957

Gait analysis is a systematic study of human locomotion, which can be utilized in variousapplications, such as rehabilitation, clinical diagnostics and sports activities. The various limitationssuch as cost, non-portability, long setup time, post-processing time etc., of the current gait analysistechniques have made them unfeasible for individual use. This led to an increase in research interestin developing smart insoles where wearable sensors can be employed to detect vertical groundreaction forces (vGRF) and other gait variables. Smart insoles are flexible, portable and comfortablefor gait analysis, and can monitor plantar pressure frequently through embedded sensors thatconvert the applied pressure to an electrical signal that can be displayed and analyzed further.Several research teams are still working to improve the insoles' features such as size, sensitivity ofinsoles sensors, durability, and the intelligence of insoles to monitor and control subjects' gait bydetecting various complications providing recommendation to enhance walking performance. Eventhough systematic sensor calibration approaches have been followed by different teams to calibrateinsoles' sensor, expensive calibration devices were used for calibration such as universal testingmachines or infrared motion capture cameras equipped in motion analysis labs. This paper providesa systematic design and characterization procedure for three different pressure sensors: forcesensitiveresistors (FSRs), ceramic piezoelectric sensors, and flexible piezoelectric sensors that canbe used for detecting vGRF using a smart insole. A simple calibration method based on a load cellis presented as an alternative to the expensive calibration techniques. In addition, to evaluate theperformance of the different sensors as a component for the smart insole, the acquired vGRF fromdifferent insoles were used to compare them. The results showed that the FSR is the most effectivesensor among the three sensors for smart insole applications, whereas the piezoelectric sensors canbe utilized in detecting the start and end of the gait cycle. This study will be useful for any researchgroup in replicating the design of a customized smart insole for gait analysis.
Overview performance of lanthanide oxide catalysts in methanation reaction for natural gas production

Rosid SJM, Toemen S, Iqbal MMA, Bakar WAWA, Mokhtar WNAW, Aziz MMA

Environ Sci Pollut Res Int, 2019 Dec;26(36):36124-36140.
PMID: 31748998 DOI: 10.1007/s11356-019-06607-8

A rapid growth in the development of power generation and transportation sectors would result in an increase in the carbon dioxide (CO2) concentration in the atmosphere. As it will continue to play a vital role in meeting current and future needs, significant efforts have been made to address this problem. Over the past few years, extensive studies on the development of heterogeneous catalysts for CO2 methanation have been investigated and reported in the literatures. In this paper, a comprehensive overview of methanation research studies over lanthanide oxide catalysts has been reviewed. The utilisation of lanthanide oxides as CO2 methanation catalysts performed an outstanding result of CO2 conversion and improvised the conversion of acidity from CO2 gas to CH4 gas. The innovations of catalysts towards the reaction were discussed in details including the influence of preparation methods, the structure-activity relationships as well as the mechanism with the purpose of outlining the pathways for future development of the methanation process.

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