Browse publications by year: 2020

  1. Amran M, Fediuk R, Vatin N, Lee YH, Murali G, Ozbakkaloglu T, et al.
    Materials (Basel), 2020 Sep 28;13(19).
    PMID: 32998362 DOI: 10.3390/ma13194323
    Foamed concrete (FC) is a high-quality building material with densities from 300 to 1850 kg/m3, which can have potential use in civil engineering, both as insulation from heat and sound, and for load-bearing structures. However, due to the nature of the cement material and its high porosity, FC is very weak in withstanding tensile loads; therefore, it often cracks in a plastic state, during shrinkage while drying, and also in a solid state. This paper is the first comprehensive review of the use of man-made and natural fibres to produce fibre-reinforced foamed concrete (FRFC). For this purpose, various foaming agents, fibres and other components that can serve as a basis for FRFC are reviewed and discussed in detail. Several factors have been found to affect the mechanical properties of FRFC, namely: fresh and hardened densities, particle size distribution, percentage of pozzolanic material used and volume of chemical foam agent. It was found that the rheological properties of the FRFC mix are influenced by the properties of both fibres and foam; therefore, it is necessary to apply an additional dosage of a foam agent to enhance the adhesion and cohesion between the foam agent and the cementitious filler in comparison with materials without fibres. Various types of fibres allow the reduction of by autogenous shrinkage a factor of 1.2-1.8 and drying shrinkage by a factor of 1.3-1.8. Incorporation of fibres leads to only a slight increase in the compressive strength of foamed concrete; however, it can significantly improve the flexural strength (up to 4 times), tensile strength (up to 3 times) and impact strength (up to 6 times). At the same time, the addition of fibres leads to practically no change in the heat and sound insulation characteristics of foamed concrete and this is basically depended on the type of fibres used such as Nylon and aramid fibres. Thus, FRFC having the presented set of properties has applications in various areas of construction, both in the construction of load-bearing and enclosing structures.
    MeSH terms: Tissue Adhesions; Construction Materials; Dietary Fiber; Hot Temperature; Nylons; Particle Size; Plastics; Polymers; Tensile Strength; Porosity; Weight-Bearing; Compressive Strength
  2. Ismail I, Arliyani, Jalil Z, Mursal, Olaiya NG, Abdullah CK, et al.
    Polymers (Basel), 2020 Sep 28;12(10).
    PMID: 32998404 DOI: 10.3390/polym12102236
    Conventionally, panel boards are produced with material flex or microparticle with P.U. or U.F. as adhesives. However, in this study, nanoparticle with epoxy resin as an adhesive was used to produce nanoboard. Coconut shell nanoparticle composite with epoxy resin as an adhesive was prepared using a compression molding technique. The coconut shell particles were originally 200 mesh size and then milled mechanically with a ball mill for the duration of 10, 20, 30, and 40 h (milling times) to produce nanoparticles. The composition ratio of the composite is 85 vol.% of coconut shell and 15 vol.% of epoxy resin. The formation of nanoparticles was observed with transmission electron microscopy (TEM). The mechanical, physical, and microstructure properties of the composite were examined with X-ray diffraction, scanning electron microscopy, atomic force microscopy, and universal testing machine. The results established that the properties of the composite (microstructures, mechanical, and physical) are influenced by the duration of milling of coconut shell particles. The modulus and flexural strength of the composite improved with an increase in the milling time. The density, thickness swelling, and porosity of the composite were also influenced by the milling times. The result suggested that the composite properties were influenced by the particle size of the coconut shell. The coconut shell nanoparticle composite can be used in the manufacturing of hybrid panels and board.
    MeSH terms: Adhesives; Cocos; Epoxy Resins; Microscopy, Electron, Scanning; Particle Size; Pressure; Surgical Mesh; X-Ray Diffraction; Porosity; Microscopy, Atomic Force; Microscopy, Electron, Transmission; Nanoparticles; Cell-Derived Microparticles
  3. Mohd Shukor NA, Seman N
    Sci Rep, 2020 Sep 30;10(1):16115.
    PMID: 32999315 DOI: 10.1038/s41598-020-72444-2
    This study focuses on the effect of different dielectric properties in the design of 3-dB planar branch line coupler (BLC) using RT5880, RO4350, TMM4 and RT6010, particularly at high frequency of 26 GHz, the fifth generation (5G) operating frequency. The analysis conducted in this study is based on the dielectric constant, loss tangent and quality factor (Q-factor) associated with the dielectric properties of the substrate materials. Accordingly, the substrate that displayed the best performance for high frequency application had the lowest dielectric constant, lowest loss tangent and highest Q-factor (i.e., RT5880), and it was chosen to enhance our proposed 3-dB BLC. This enhanced 3-dB BLC was designed with the inclusion of microstrip-slot stub impedance at each port for bandwidth enhancement, and the proposed prototype had dimensions of 29.9 mm × 19.9 mm. The design and analysis of the proposed 3-dB BLC were accomplished by employing CST Microwave Studio. The performance of scattering parameters and the phase difference of the proposed BLC were then assessed and verified through laboratory measurement.
  4. Foong LC, Chai JY, Ho ASH, Yeo BPH, Lim YM, Tam SM
    Sci Rep, 2020 09 30;10(1):16123.
    PMID: 32999341 DOI: 10.1038/s41598-020-72997-2
    Impatiens balsamina L. is a tropical ornamental and traditional medicinal herb rich in natural compounds, especially 2-methoxy-1,4-naphthoquinone (MNQ) which is a bioactive compound with tested anticancer activities. Characterization of key genes involved in the shikimate and 1,4-dihydroxy-2-naphthoate (DHNA) pathways responsible for MNQ biosynthesis and their expression profiles in I. balsamina will facilitate adoption of genetic/metabolic engineering or synthetic biology approaches to further increase production for pre-commercialization. In this study, HPLC analysis showed that MNQ was present in significantly higher quantities in the capsule pericarps throughout three developmental stages (early-, mature- and postbreaker stages) whilst its immediate precursor, 2-hydroxy-1,4-naphthoquinone (lawsone) was mainly detected in mature leaves. Transcriptomes of I. balsamina derived from leaf, flower, and three capsule developmental stages were generated, totalling 59.643 Gb of raw reads that were assembled into 94,659 unigenes (595,828 transcripts). A total of 73.96% of unigenes were functionally annotated against seven public databases and 50,786 differentially expressed genes (DEGs) were identified. Expression profiles of 20 selected genes from four major secondary metabolism pathways were studied and validated using qRT-PCR method. Majority of the DHNA pathway genes were found to be significantly upregulated in early stage capsule compared to flower and leaf, suggesting tissue-specific synthesis of MNQ. Correlation analysis identified 11 candidate unigenes related to three enzymes (NADH-quinone oxidoreductase, UDP-glycosyltransferases and S-adenosylmethionine-dependent O-methyltransferase) important in the final steps of MNQ biosynthesis based on genes expression profiles consistent with MNQ content. This study provides the first molecular insight into the dynamics of MNQ biosynthesis and accumulation across different tissues of I. balsamina and serves as a valuable resource to facilitate further manipulation to increase production of MNQ.
    MeSH terms: Naphthoquinones/metabolism*; Plants, Medicinal/genetics; Plants, Medicinal/metabolism; Gene Expression Regulation, Plant/genetics; Plant Leaves/genetics; Plant Leaves/metabolism; Gene Expression Profiling/methods; Impatiens/genetics*; Impatiens/metabolism; Flowers/genetics; Flowers/metabolism; Molecular Sequence Annotation/methods; Transcriptome/genetics*; Gene Ontology
  5. Ng FL, Phang SM, Lan BL, Kalavally V, Thong CH, Chong KT, et al.
    Sci Rep, 2020 09 30;10(1):16105.
    PMID: 32999346 DOI: 10.1038/s41598-020-72823-9
    The biophotovoltaic cell (BPV) is deemed to be a potent green energy device as it demonstrates the generation of renewable energy from microalgae; however, inadequate electron generation from microalgae is a significant impediment for functional employment of these cells. The photosynthetic process is not only affected by the temperature, CO2 concentration and light intensity but also the spectrum of light. Thus, a detailed understanding of the influences of light spectrum is essential. Accordingly, we developed spectrally optimized light using programmable LED arrays (PLA)s to study the effect on algae growth and bioelectricity generation. Chlorella is a green microalga and contains chlorophyll-a (chl-a), which is the major light harvesting pigment that absorbs light in the blue and red spectrum. In this study, Chlorella is grown under a PLA which can optimally simulate the absorption spectrum of the pigments in Chlorella. This experiment investigated the growth, photosynthetic performance and bioelectricity generation of Chlorella when exposed to an optimally-tuned light spectrum. The algal BPV performed better under PLA with a peak power output of 0.581 mW m-2 for immobilized BPV device on day 8, which is an increase of 188% compared to operation under a conventional white LED light source. The photosynthetic performance, as measured using pulse amplitude modulation (PAM) fluorometry, showed that the optimized spectrum from the PLA gave an increase of 72% in the rETRmax value (190.5 μmol electrons m-2 s-1), compared with the conventional white light source. Highest algal biomass (1100 mg L-1) was achieved in the immobilized system on day eight, which translates to a carbon fixation of 550 mg carbon L-1. When artificial light is used for the BPV system, it should be optimized with the light spectrum and intensity best suited to the absorption capability of the pigments in the cells. Optimum artificial light source with algal BPV device can be integrated into a power management system for low power application (eg. environment sensor for indoor agriculture system).
  6. Babu MGR, Kadavigere R, Koteshwara P, Sathian B, Rai KS
    Sci Rep, 2020 09 30;10(1):16177.
    PMID: 32999361 DOI: 10.1038/s41598-020-73221-x
    Studies provide evidence that practicing meditation enhances neural plasticity in reward processing areas of brain. No studies till date, provide evidence of such changes in Rajyoga meditation (RM) practitioners. The present study aimed to identify grey matter volume (GMV) changes in reward processing areas of brain and its association with happiness scores in RM practitioners compared to non-meditators. Structural MRI of selected participants matched for age, gender and handedness (n = 40/group) were analyzed using voxel-based morphometric method and Oxford Happiness Questionnaire (OHQ) scores were correlated. Significant increase in OHQ happiness scores were observed in RM practitioners compared to non-meditators. Whereas, a trend towards significance was observed in more experienced RM practitioners, on correlating OHQ scores with hours of meditation experience. Additionally, in RM practitioners, higher GMV were observed in reward processing centers-right superior frontal gyrus, left inferior orbitofrontal cortex (OFC) and bilateral precuneus. Multiple regression analysis showed significant association between OHQ scores of RM practitioners and reward processing regions right superior frontal gyrus, left middle OFC, right insula and left anterior cingulate cortex. Further, with increasing hours of RM practice, a significant positive association was observed in bilateral ventral pallidum. These findings indicate that RM practice enhances GMV in reward processing regions associated with happiness.
    MeSH terms: Adult; Brain Mapping; Female; Happiness*; Humans; Magnetic Resonance Imaging; Male; Middle Aged; Neuronal Plasticity/physiology*; Organ Size; Reward*; Meditation/psychology*
  7. Jamshed S, Bhagavathula AS, Zeeshan Qadar SM, Alauddin U, Shamim S, Hasan S
    Hosp Pharm, 2020 Oct;55(5):292-305.
    PMID: 32999499 DOI: 10.1177/0018578719893378
    Background: Gastroesophageal reflux disease (GERD) is a common gastrointestinal disorder that results from regurgitation of acid from the stomach into the esophagus. Treatment available for GERD includes lifestyle changes, antacids, histamine-2 receptor antagonists (H2RAs), proton pump inhibitors (PPIs), and anti-reflux surgery. Aim: The aim of this review is to assess the cost-effectiveness of the use of PPIs in the long-term management of patients with GERD. Method: We searched in PubMed to identify related original articles with close consideration based on inclusion and exclusion criteria to choose the best studies for this narrative review. The first section compares the cost-effectiveness of PPIs with H2RAs in long-term heartburn management. The other sections shall only discuss the cost-effectiveness of PPIs in 5 different strategies, namely, continuous (step-up, step-down, and maintenance), on-demand, and intermittent therapies. Results: Of 55 articles published, 10 studies published from 2000 to 2015 were included. Overall, PPIs are more effective in relieving heartburn in comparison with ranitidine. The use of PPIs in managing heartburn in long-term consumption of nonsteroidal anti-inflammatory drug (NSAID) has higher cost compared with H2RA. However, if the decision-maker is willing to pay more than US$174 788.60 per extra quality-adjusted life year (QALY), then the optimal strategy is traditional NSAID (tNSAID) and PPIs. The probability of being cost-effective was also highest for NSAID and PPI co-therapy users. On-demand PPI treatment strategy showed dominant with an incremental cost-effectiveness ratio of US$2197 per QALY gained and was most effective and cost saving compared with all the other treatments. The average cost-effectiveness ratio was lower for rabeprazole therapy than for ranitidine therapy. Conclusion: Our review revealed that long-term treatment with PPIs is effective but costly. To achieve long-term cost-effective approach, we recommend on-demand approach to treat heartburn symptoms, but if the symptoms persist, treatment with continuous step-down therapy should be applied.
  8. Brandt MJ, Kuppens T, Spears R, Andrighetto L, Autin F, Babincak P, et al.
    Eur J Soc Psychol, 2020 Aug;50(5):921-942.
    PMID: 32999511 DOI: 10.1002/ejsp.2694
    The relationships between subjective status and perceived legitimacy are important for understanding the extent to which people with low status are complicit in their oppression. We use novel data from 66 samples and 30 countries (N = 12,788) and find that people with higher status see the social system as more legitimate than those with lower status, but there is variation across people and countries. The association between subjective status and perceived legitimacy was never negative at any levels of eight moderator variables, although the positive association was sometimes reduced. Although not always consistent with hypotheses, group identification, self-esteem, and beliefs in social mobility were all associated with perceived legitimacy among people who have low subjective status. These findings enrich our understanding of the relationship between social status and legitimacy.
  9. Loh HH, Kamaruddin NA
    Ann Acad Med Singap, 2020 Jul;49(7):468-476.
    PMID: 33000110
    During Ramadan, Muslims fast from sunrise (Sahur) to sunset (Iftar) and are required to abstain from food and fluids, including oral and injectable medications. Patients with diabetes who fast during Ramadan are at risk of developing hyperglycemia with increased risk of ketoacidosis, hypoglycemia, dehydration and thrombosis. Pre-Ramadan education and preparation of a fasting patient are essential to reduce severe complications. This review paper summarizes studies to date on oral and injectable medications available for patients with type 2 diabetes during Ramadan fasting, as well as recommendations on management of these patients during Ramadan. Although there is limited data on the use of Metformin, Acarbose and Thiazolidinedione in Ramadan, they appear to be safe. Sulphonylurea, especially Glibenclamide, is associated with higher risk of hypoglycemia during Ramadan fasting, hence may need adjustment in dosing and timing. The incretin group and SGLT2 inhibitor use during Ramadan fasting is associated with low risk of hypoglycemia with no increased adverse events. Insulin regimes need to be individualized for patients who fast during Ramadan.
    MeSH terms: Dehydration; Diabetes Mellitus, Type 2; Glyburide; Humans; Hyperglycemia; Hypoglycemia; Islam; Ketosis; Metformin; Sulfonylurea Compounds; Thrombosis; Acarbose; Thiazolidinediones; Sodium-Glucose Transporter 2; Incretins
  10. Teng S, Khong KW, Pahlevan Sharif S, Ahmed A
    JMIR Public Health Surveill, 2020 10 01;6(4):e19618.
    PMID: 33001036 DOI: 10.2196/19618
    BACKGROUND: Poor nutrition and food selection lead to health issues such as obesity, cardiovascular disease, diabetes, and cancer. This study of YouTube comments aims to uncover patterns of food choices and the factors driving them, in addition to exploring the sentiments of healthy eating in networked communities.

    OBJECTIVE: The objectives of the study are to explore the determinants, motives, and barriers to healthy eating behaviors in online communities and provide insight into YouTube video commenters' perceptions and sentiments of healthy eating through text mining techniques.

    METHODS: This paper applied text mining techniques to identify and categorize meaningful healthy eating determinants. These determinants were then incorporated into hypothetically defined constructs that reflect their thematic and sentimental nature in order to test our proposed model using a variance-based structural equation modeling procedure.

    RESULTS: With a dataset of 4654 comments extracted from YouTube videos in the context of Malaysia, we apply a text mining method to analyze the perceptions and behavior of healthy eating. There were 10 clusters identified with regard to food ingredients, food price, food choice, food portion, well-being, cooking, and culture in the concept of healthy eating. The structural equation modeling results show that clusters are positively associated with healthy eating with all P values less than .001, indicating a statistical significance of the study results. People hold complex and multifaceted beliefs about healthy eating in the context of YouTube videos. Fruits and vegetables are the epitome of healthy foods. Despite having a favorable perception of healthy eating, people may not purchase commonly recognized healthy food if it has a premium price. People associate healthy eating with weight concerns. Food taste, variety, and availability are identified as reasons why Malaysians cannot act on eating healthily.

    CONCLUSIONS: This study offers significant value to the existing literature of health-related studies by investigating the rich and diverse social media data gleaned from YouTube. This research integrated text mining analytics with predictive modeling techniques to identify thematic constructs and analyze the sentiments of healthy eating.

    MeSH terms: Cardiovascular Diseases; Cooking; Diabetes Mellitus; Feeding Behavior; Food Preferences; Fruit; Humans; Malaysia; Motivation; Neoplasms; Obesity; Perception; Taste; Vegetables; Data Mining; Social Media
  11. Toh S, Yew DCM, Choong JJ, Chong TL, Harky A
    J Card Surg, 2020 Dec;35(12):3432-3439.
    PMID: 33001480 DOI: 10.1111/jocs.15070
    OBJECTIVE: We sought to compare clinical outcomes in patients with acute type A aortic dissection that undergone surgical repair during in-hours (IH) versus out-of-hours (OOH).

    METHODS: An electronic literature search was done till March 2020 to include studies with comparative cohorts of IH versus OOH. Primary outcomes were 30-day mortality, stroke, and reoperation for bleeding; secondary outcomes were acute kidney injury, total hospital stay, and intensive care unit stay.

    RESULTS: Six articles with a total of 3744 patients met the inclusion criteria. Mean age was similar, 60 ± 12 versus 60 ± 13 in IH versus OOH (p = .25). Aortic root and total arch replacement were similar in both cohorts, 22% in IH versus 25% in OOH (risk ratio [RR], 1.10; 95% confidence interval [CI: 0.78, 1.55]; p = .58) and 29% in IH versus 32% in OOH (RR, 0.96; 95% CI [0.89, 1.04], p = .37) respectively. Reoperation for bleeding and stroke rate were similar, with 18% in IH versus 23% in OOH (RR, 0.89; 95% CI [0.73, 1.08]; p = .24), and 12% in IH versus 13% in OOH (RR, 0.83; 95% CI [0.66, 1.03]; p = .09) respectively. Thirty-day mortality was significantly lower in IH (RR, 0.81; 95% CI [0.72, 0.90]; p = .0001).

    CONCLUSION: There was higher 30-day mortality rate during OOH surgery, yet this difference diminished following sensitivity analysis. There were no significant differences in major postoperative outcomes. Therefore, operating on such cases should be decided on clinical priority without delay.

    MeSH terms: Humans; Reoperation; Odds Ratio; After-Hours Care*
  12. Ahmed S, Kreft A, Chowdhury EH, Hossain SM, Galle PR, Neumann H
    PLoS One, 2020;15(10):e0239814.
    PMID: 33002048 DOI: 10.1371/journal.pone.0239814
    BACKGROUND AND STUDY AIMS: Despite major technical advancements, endoscopic surveillance for detecting premalignant lesions in Barrett's esophagus is challenging because of their flat appearance with only subtle morphological changes. Molecular endoscopic imaging (MEI) using nanoparticles (NPs), coupled with fluorescently labeled antibody permits visualization of disease-specific molecular alterations. The aim of this ex vivo study was to assess the diagnostic applicability of MEI with NPs to detect Barrett's metaplasia.

    PATIENTS AND METHODS: Seven patients undergoing endoscopic surveillance of known Barrett's esophagus were recruited. Freshly resected biopsy specimens were incubated with NPs coupled with FITC labeled Muc-2 antibodies and examined with MEI. Fluorescence intensity from Barrett's mucosa and control specimens were compared, followed by histological confirmation.

    RESULTS: Fluorescence signals, indicating the presence of goblet cells, were noted for traditional MEI using Muc-2 antibodies in Barrett's intestinal metaplasia. Significantly stronger fluorescence signals were achieved with NPs coupled with FITC-conjugated Muc-2 antibodies. The results of MEI with NPs for the prediction of Barrett's metaplasia correlated with the final histopathological examination in all the cases.

    CONCLUSIONS: Highly-specific NPs detected Barrett's metaplasia more efficiently than conventional MEI in this first feasibility study. MEI was as effective as standard histopathology for identifying Muc-2 containing goblet cells for diagnosis of Barrett's metaplasia. (DRKS-ID: DRKS00017747).

    MeSH terms: Aged; Antibodies/immunology; Antibodies/chemistry; Barrett Esophagus/pathology; Endoscopy/methods*; Humans; Middle Aged; Mucins/immunology; Fluorescein-5-isothiocyanate/chemistry; Nanoconjugates/chemistry*; Optical Imaging/methods*
  13. Tan LT, Nathan AM, Jayanath S, Eg KP, Thavagnanam S, Lum LCS, et al.
    Pediatr Pulmonol, 2020 12;55(12):3477-3486.
    PMID: 33002341 DOI: 10.1002/ppul.25083
    BACKGROUND: Provision of home mechanical ventilation (HMV) to children with chronic respiratory insufficiency enhances growth and quality of life. The hypothesis was that health-related quality of life (HRQoL) and the development of these children were poorer than in healthy children.

    OBJECTIVES: To determine the HRQoL and developmental outcome of children on HMV.

    METHODS: This cross-sectional study used the TNO-AZL Preschool children's Quality Of Life (TAPQOL; <5 years old) and Health Utilities Index (HUI) 2/3 (≥5 years old) to assess the quality of life and the Schedule of Growing Skills-II to assess development. Instruments were used on children currently or previously on HMV (≥3 months) and compared with age and sex-matched controls.

    RESULTS: Sixty-five patients and 130 controls were recruited. Patients' median (interquartile range) age was 3.12 (1.65, 5.81) years. Patients had significantly lower TAPQOL scores in the domains of lung, liveliness, positive mood, social functioning, motor functioning, and communication, and lower HUI 2/3 scores in hearing, sensation, pain, speech, mobility, ambulatory, dexterity, and self-care domains. The developmental outcome of patients was poorer in all domains. However, patients had fewer behavioral problems. Those with respiratory tract disease and without comorbidities had better HRQoL and developmental scores. Having a parent as the primary caregiver was associated with better speech and language skills.

    CONCLUSIONS: HRQoL and the developmental outcome are lower in children on HMV compared to controls. Children with respiratory tract disease and without comorbidities have a better outcome. Parents play a crucial role in the acquisition of speech.

    MeSH terms: Child, Preschool; Cross-Sectional Studies; Developing Countries; Female; Humans; Male; Parents; Quality of Life*; Respiration, Artificial*; Comorbidity; Caregivers
  14. Anwar F, Saleem U, Ahmad B, Ashraf M, Rehman AU, Froeyen M, et al.
    Comput Biol Chem, 2020 Dec;89:107378.
    PMID: 33002716 DOI: 10.1016/j.compbiolchem.2020.107378
    Neurodegenerative diseases have complex etiology and pose a challenge to scientists to develop simple and cost-effective synthetic compounds as potential drug candidates for such diseases. Here, we report an extension of our previously published in silico screening, where we selected four new compounds as AChE inhibitors. Further, based on favorable binding possess, MD simulation and MMGBSA, two most promising compounds (3a and 3b) were selected, keeping in view the ease of synthesis and cost-effectiveness. Due to the critical role of BChE, LOX and α-glucosidase in neurodegeneration, the selected compounds were also screened against these enzymes. The IC50 values of 3a against AChE and BChE found to be 12.53 and 352.42 μM, respectively. Moderate to slight inhibitions of 45.26 % and 28.68 % were presented by 3a against LOX and α-glucosidase, respectively, at 0.5 mM. Insignificant inhibitions were observed with 3b against the four selected enzymes. Further, in vivo trial demonstrated that 3a could significantly diminish AChE levels in the mice brain as compared to the control. These findings were in agreement with the histopathological analysis of the brain tissues. The results corroborate that selected compounds could serve as a potential lead for further development and optimization as AChE inhibitors to achieve cost-effective anti-Alzheimer's drugs.
    MeSH terms: Acetylcholinesterase/metabolism*; Alzheimer Disease/drug therapy; Alzheimer Disease/enzymology; Animals; Brain/drug effects; Butyrylcholinesterase/metabolism; Cholinesterase Inhibitors/chemical synthesis; Cholinesterase Inhibitors/metabolism; Cholinesterase Inhibitors/pharmacology*; Female; Male; Naphthalenes/chemical synthesis; Naphthalenes/metabolism; Naphthalenes/pharmacology*; Thermodynamics; Mice; Molecular Dynamics Simulation; Molecular Docking Simulation
  15. Gazali AM, Schroderus AM, Näntö-Salonen K, Rintamäki R, Pihlajamäki J, Knip M, et al.
    Diabetologia, 2020 11;63(11):2396-2409.
    PMID: 32880687 DOI: 10.1007/s00125-020-05257-7
    AIMS/HYPOTHESIS: Mucosal-associated invariant T (MAIT) cells are innate-like T cells that recognise derivatives of bacterial riboflavin metabolites presented by MHC-Ib-related protein 1 (MR1) molecules and are important effector cells for mucosal immunity. Their development can be influenced by the intestinal microbiome. Since the development of type 1 diabetes has been associated with changes in the gut microbiome, this can be hypothesised to lead to alterations in circulating MAIT cells. Accordingly, peripheral blood MAIT cell alterations have been reported previously in patients with type 1 diabetes. However, a comprehensive analysis of the frequency and phenotype of circulating MAIT cells at different stages of type 1 diabetes progression is currently lacking.

    METHODS: We analysed the frequency, phenotype and functionality of peripheral blood MAIT cells, as well as γδ T cells, invariant natural killer T (iNKT) cells and natural killer (NK) cells with flow cytometry in a cross-sectional paediatric cohort (aged 2-15) consisting of 51 children with newly diagnosed type 1 diabetes, 27 autoantibody-positive (AAb+) at-risk children, and 113 healthy control children of similar age and HLA class II background. The frequency of MAIT cells was also assessed in a separate cross-sectional adult cohort (aged 19-39) of 33 adults with established type 1 diabetes and 37 healthy individuals of similar age.

    RESULTS: Children with newly diagnosed type 1 diabetes displayed a proportional increase of CD8-CD27- MAIT cells compared with healthy control children (median 4.6% vs 3.1% of MAIT cells, respectively, p = 0.004), which was associated with reduced expression of C-C chemokine receptor (CCR)5 (median 90.0% vs 94.3% of MAIT cells, p = 0.02) and β7 integrin (median 73.5% vs 81.7% of MAIT cells, p = 0.004), as well as decreased production of IFN-γ (median 57.1% vs 69.3% of MAIT cells, p = 0.04) by the MAIT cells. The frequency of MAIT cells was also decreased in AAb+ children who later progressed to type 1 diabetes compared with healthy control children (median 0.44% vs 0.96% of CD3+ T cells, p = 0.04), as well as in adult patients with a short duration of type 1 diabetes (less than 6 years after diagnosis) compared with control individuals (median 0.87% vs 2.19% of CD3+ T cells, p = 0.007). No alterations in γδ T cell, iNKT cell or NK cell frequencies were observed in children with type 1 diabetes or in AAb+ children, with the exception of an increased frequency of IL-17A+ γδ T cells in children with newly diagnosed diabetes compared with healthy control children (median 1.58% vs 1.09% of γδ T cells, p = 0.002).

    CONCLUSIONS/INTERPRETATION: Changes in the frequency and phenotype of circulating MAIT cells were detectable before, at the onset and after diagnosis of type 1 diabetes in cross-sectional cohorts. Our results suggest a possible temporal association between peripheral blood MAIT cell alterations and the clinical onset of type 1 diabetes. Graphical abstract.

    MeSH terms: Gastrointestinal Microbiome; Adolescent; Adult; Aged; Child; Child, Preschool; Cross-Sectional Studies; Diabetes Mellitus, Type 1; Flow Cytometry; Humans; Killer Cells, Natural; Phenotype; Riboflavin; Cohort Studies; CD8-Positive T-Lymphocytes; Immunity, Mucosal; Receptors, Chemokine; Chemokines, CC; Interleukin-17; Integrin beta Chains; Natural Killer T-Cells; Young Adult; Mucosal-Associated Invariant T Cells
  16. Lange E, Lozano AI, Jones NC, Hoffmann SV, Kumar S, Śmiałek MA, et al.
    J Phys Chem A, 2020 Sep 30.
    PMID: 32941031 DOI: 10.1021/acs.jpca.0c06615
    We investigate the methanol absorption spectrum in the range 5.5-10.8 eV to provide accurate and absolute cross-sections values. The main goal of this study is to provide a comprehensive analysis of methanol electronic-state spectroscopy by employing high-resolution vacuum ultraviolet (VUV) photoabsorption measurements together with state-of-the-art quantum chemical calculation methods. The VUV spectrum reveals several new features that are not previously reported in literature, for n > 3 in the transitions (nsσ(a') ← (2a″)) (1A' ← X̃1A') and (nsσ, npσ, npσ', ndσ ← (7a')) (1A' ← X̃1A'), and with particular relevance to vibrational progressions of the CH3 rocking mode, v11'(a″), mode in the (3pπ(a″) ← (2a″)) (21A' ← X̃1A') absorption band at 8.318 eV. The measured absolute photoabsorption cross-sections have subsequently been used to calculate the photolysis lifetime of methanol in the Earth's atmosphere from the ground level up to the limit of the stratosphere (50 km altitude). This shows that solar photolysis plays a negligible role in the removal of methanol from the lower atmosphere compared with competing sink mechanisms. Torsional potential energy scans, as a function of the internal rotation angle for the ground and first Rydberg states, have also been calculated as part of this investigation.
    MeSH terms: Methanol; Altitude; Atmosphere; Goals; Photolysis; Rotation; Spectrum Analysis; Vacuum; Vibration
  17. Sapuan SM, Aulia HS, Ilyas RA, Atiqah A, Dele-Afolabi TT, Nurazzi MN, et al.
    Polymers (Basel), 2020 Sep 27;12(10).
    PMID: 32992450 DOI: 10.3390/polym12102211
    This work represents a study to investigate the mechanical properties of longitudinal basalt/woven-glass-fiber-reinforced unsaturated polyester-resin hybrid composites. The hybridization of basalt and glass fiber enhanced the mechanical properties of hybrid composites. The unsaturated polyester resin (UP), basalt (B) and glass fibers (GF) were fabricated using the hand lay-up method in six formulations (UP, GF, B7.5/G22.5, B15/G15, B22.5/G7.5 and B) to produce the composites, respectively. This study showed that the addition of basalt to glass-fiber-reinforced unsaturated polyester resin increased its density, tensile and flexural properties. The tensile strength of the B22.5/G7.5 hybrid composites increased by 213.92 MPa compared to neat UP, which was 8.14 MPa. Scanning electron microscopy analysis was used to observe the fracture mode and fiber pullout of the hybrid composites.
    MeSH terms: Dental Materials; Glass; Microscopy, Electron, Scanning; Polyesters; Tensile Strength; Silicates
  18. Nazrin A, Sapuan SM, Zuhri MYM
    Polymers (Basel), 2020 Sep 27;12(10).
    PMID: 32992514 DOI: 10.3390/polym12102216
    In this paper, sugar palm nanocellulose fibre-reinforced thermoplastic starch (TPS)/poly (lactic acid) (PLA) blend bionanocomposites were prepared using melt blending and compression moulding with different TPS concentrations (20%, 30%, 40%, 60%, and 80%) and constant sugar palm nanocellulose fibres (0.5%). The physical, mechanical, thermal, and water barrier properties were investigated. The SEM images indicated different TPS loading effects with the morphology of the blend bionanocomposites due to their immiscibility. A high content of TPS led to agglomeration, while a lower content resulted in the presence of cracks and voids. The 20% TPS loading reduced the tensile strength from 49.08 to 19.45 MPa and flexural strength from 79.60 to 35.38 MPa. The thermal stability of the blend bionanocomposites was reduced as the TPS loading increased. The thickness swelling, which corresponded to the water absorption, demonstrated an increasing trend with the increased addition of TPS loading.
    MeSH terms: Dietary Fiber; Plant Extracts; Polyesters; Starch; Tensile Strength; Water; Lactic Acid
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