Displaying publications 61 - 80 of 106 in total

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  1. Molecularly imprinted polymer for the removal of diclofenac from water: Synthesis and characterization
    Samah NA, Sánchez-Martín MJ, Sebastián RM, Valiente M, López-Mesas M
    Sci Total Environ, 2018 Aug 01;631-632:1534-1543.
    PMID: 29727977 DOI: 10.1016/j.scitotenv.2018.03.087
    Contaminants of Emerging Concerns (CECs) have been introduced as one type of recalcitrant pollutant sources in water. In this study, the non-steroidal anti-inflammatory drug diclofenac (DCF) has been removed from water solutions using Molecularly Imprinted Polymer (MIP), synthetized via bulk polymerization with allylthiourea (AT) as the functional monomer and using DCF as template (MIP-DCF). DCF detection has been performed by UV spectrophotometer. From the kinetic study in batch mode, approximately 100% of removal is observed by using 10mg of MIP-DCF, with an initial concentration of 5mg/L of DCF at pH7, within 3min and agitated at 25°C. In continuous flow mode study, using a cartridge pre-packed with 10mg of MIP-DCF, a high adsorption capacity of 160mgDCF/g MIP was obtained. To study the porosity of MIPs, scanning electron microscopy (SEM) has been used. In order to characterize the chemical interaction between monomer and template, the pre-polymerization mixture for MIP and DCF has also been studied by 1H NMR. One of the chemical shift observed has been related to the formation of a complex between amine protons of thiourea group of AT with carboxylic acid on DCF. In conclusion, the developed MIP works as a good adsorbent for DCF removal, and is selective to DCF in the presence of indomethacin and ibuprofen.
    Matched MeSH terms: Proton Magnetic Resonance Spectroscopy
  2. Multinuclear MR and multilevel data processing: an insight into morphologic assessment of in vivo knee articular cartilage
    Hani AF, Kumar D, Malik AS, Walter N, Razak R, Kiflie A
    Acad Radiol, 2015 Jan;22(1):93-104.
    PMID: 25481518 DOI: 10.1016/j.acra.2014.08.008
    Quantitative assessment of knee articular cartilage (AC) morphology using magnetic resonance (MR) imaging requires an accurate segmentation and 3D reconstruction. However, automatic AC segmentation and 3D reconstruction from hydrogen-based MR images alone is challenging because of inhomogeneous intensities, shape irregularity, and low contrast existing in the cartilage region. Thus, the objective of this research was to provide an insight into morphologic assessment of AC using multilevel data processing of multinuclear ((23)Na and (1)H) MR knee images.
    Matched MeSH terms: Proton Magnetic Resonance Spectroscopy/methods*
  3. Multiple crystallization as a potential strategy for efficient recovery of succinic acid following fermentation with immobilized cells
    Luthfi AAI, Tan JP, Isa NFAM, Bukhari NA, Shah SSM, Mahmod SS, et al.
    Bioprocess Biosyst Eng, 2020 Jul;43(7):1153-1169.
    PMID: 32095989 DOI: 10.1007/s00449-020-02311-x
    This study aimed to enhance the crystallizability of bio-based succinic acid for its efficient recovery while maintaining the end product at the highest purity. Immobilization of Actinobacillus succinogenes was initially evaluated based on three different carriers: volcanic glass, clay pebbles, and silica particles. The adsorption capacity of metabolites with a low concentration (10 g/L) and a high concentration (40 g/L) was investigated. It was demonstrated that clay pebbles adsorbed the least succinic acid (
    Matched MeSH terms: Proton Magnetic Resonance Spectroscopy
  4. N,N-dimethylhexadecyl carboxymethyl chitosan as a potential carrier agent for rotenone
    Kamari A, Aljafree NF, Yusoff SN
    Int J Biol Macromol, 2016 Jul;88:263-72.
    PMID: 27041651 DOI: 10.1016/j.ijbiomac.2016.03.071
    In this study, an amphiphilic chitosan derivative namely N,N-dimethylhexadecyl carboxymethyl chitosan (DCMC) was synthesised and applied for the first time as a carrier agent for rotenone. The physical and chemical properties of DCMC were characterised by using Fourier Transform Infrared Spectrometer (FTIR), Proton Nuclear Magnetic Resonance Spectrometer ((1)H NMR), CHN-O Elemental Analyser, Thermogravimetric Analyser (TGA) and Differential Scanning Calorimeter (DSC). DCMC was soluble in acidic (except pH 4), neutral and basic media with percent of transmittance (%T) values ranged from 67.2 to 99.4%. The critical micelle concentration (CMC) was determined as 0.095mg/mL. Transmission Electron Microscopy (TEM) analysis confirmed that DCMC has formed self-aggregates and exhibited spherical shape with the size of 65.5-137.0nm. The encapsulation efficiency (EE) and loading capacity (LC) of DCMC micelles with different weight ratios (DCMC:rotenone; 5:1, 50:1 and 100:1) were determined by using High Performance Liquid Chromatography (HPLC). The weight ratio of 100:1 gave the best EE with the value of more than 95.0%. DCMC micelles performed an excellent ability to control the release of rotenone, of which 99.0% of rotenone was released within 48h. Overall, DCMC has several key features to be an effective carrier agent for pesticide formulations.
    Matched MeSH terms: Proton Magnetic Resonance Spectroscopy
  5. Fulltext NMR-Based Metabolomics Profiling for Radical Scavenging and Anti-Aging Properties of Selected Herbs
    Hussin M, Abdul Hamid A, Abas F, Ramli NS, Jaafar AH, Roowi S, et al.
    Molecules, 2019 Sep 03;24(17).
    PMID: 31484470 DOI: 10.3390/molecules24173208
    Herbs that are usually recognized as medicinal plants are well known for their therapeutic effects and are traditionally used to treat numerous diseases, including aging. This study aimed to evaluate the metabolite variations among six selected herbs namely Curcurmalonga, Oenanthejavanica, Vitex negundo, Plucheaindica, Cosmoscaudatus and Persicariaminus using proton nuclear magnetic resonance (1H-NMR) coupled with multivariate data analysis (MVDA). The free radical scavenging activity of the extract was measured by 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2-azinobis(3-ethyl-benzothiazoline-6-sulfonic acid) (ABTS) and oxygen radical absorbance capacity (ORAC) assay. The anti-aging property was characterized by anti-elastase and anti-collagenase inhibitory activities. The results revealed that P. minus showed the highest radical scavenging activities and anti-aging properties. The partial least squares (PLS) biplot indicated the presence of potent metabolites in P. minus such as quercetin, quercetin-3-O-rhamnoside (quercitrin), myricetin derivatives, catechin, isorhamnetin, astragalin and apigenin. It can be concluded that P. minus can be considered as a potential source for an anti-aging ingredient and also a good free radical eradicator. Therefore, P. minus could be used in future development in anti-aging researches and medicinal ingredient preparations.
    Matched MeSH terms: Proton Magnetic Resonance Spectroscopy
  6. Neurometabolites Alteration in the Acute Phase of Mild Traumatic Brain Injury (mTBI): An In Vivo Proton Magnetic Resonance Spectroscopy (1H-MRS) Study
    Veeramuthu V, Seow P, Narayanan V, Wong JHD, Tan LK, Hernowo AT, et al.
    Acad Radiol, 2018 09;25(9):1167-1177.
    PMID: 29449141 DOI: 10.1016/j.acra.2018.01.005
    RATIONALE AND OBJECTIVES: Magnetic resonance spectroscopy is a noninvasive imaging technique that allows for reliable assessment of microscopic changes in brain cytoarchitecture, neuronal injuries, and neurochemical changes resultant from traumatic insults. We aimed to evaluate the acute alteration of neurometabolites in complicated and uncomplicated mild traumatic brain injury (mTBI) patients in comparison to control subjects using proton magnetic resonance spectroscopy (1H magnetic resonance spectroscopy).

    MATERIAL AND METHODS: Forty-eight subjects (23 complicated mTBI [cmTBI] patients, 12 uncomplicated mTBI [umTBI] patients, and 13 controls) underwent magnetic resonance imaging scan with additional single voxel spectroscopy sequence. Magnetic resonance imaging scans for patients were done at an average of 10 hours (standard deviation 4.26) post injury. The single voxel spectroscopy adjacent to side of injury and noninjury regions were analysed to obtain absolute concentrations and ratio relative to creatine of the neurometabolites. One-way analysis of variance was performed to compare neurometabolite concentrations of the three groups, and a correlation study was done between the neurometabolite concentration and Glasgow Coma Scale.

    RESULTS: Significant difference was found in ratio of N-acetylaspartate to creatine (NAA/Cr + PCr) (χ2(2) = 0.22, P 

    Matched MeSH terms: Proton Magnetic Resonance Spectroscopy*
  7. Fulltext New cholinesterase inhibitory constituents from Lonicera quinquelocularis
    Khan D, Khan HU, Khan F, Khan S, Badshah S, Khan AS, et al.
    PLoS One, 2014;9(4):e94952.
    PMID: 24733024 DOI: 10.1371/journal.pone.0094952
    A phytochemical investigation on the ethyl acetate soluble fraction of Lonicera quinquelocularis (whole plant) led to the first time isolation of one new phthalate; bis(7-acetoxy-2-ethyl-5-methylheptyl) phthalate (3) and two new benzoates; neopentyl-4-ethoxy-3, 5-bis (3-methyl-2-butenyl benzoate (4) and neopentyl-4-hydroxy-3, 5-bis (3-methyl-2-butenyl benzoate (5) along with two known compounds bis (2-ethylhexyl phthalate (1) and dioctyl phthalate (2). Their structures were established on the basis of spectroscopic analysis and by comparison with available data in the literature. All the compounds (1-5) were tested for their acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory activities in dose dependent manner. The IC50 (50% inhibitory effect) values of compounds 3 and 5 against AChE were 1.65 and 3.43 µM while the values obtained against BChE were 5.98 and 9.84 µM respectively. Compounds 2 and 4 showed weak inhibition profile.
    Matched MeSH terms: Proton Magnetic Resonance Spectroscopy
  8. Fulltext Novel Bi-heterocycles as Potent Inhibitors of Urease and Less Cytotoxic Agents: 3-({5-((2-Amino-1,3-thiazol-4-yl)methyl)-1,3,4-oxadiazol-2-yl}sulfanyl)-N-(un/substituted-phenyl)propanamides
    Abbasi MA, Ramzan MS, Ur-Rehman A, Siddiqui SZ, Hassan M, Ali Shah SA, et al.
    Iran J Pharm Res, 2020;19(1):487-506.
    PMID: 32922502 DOI: 10.22037/ijpr.2019.13084.11362
    The synthesis of a novel series of bi-heterocyclic propanamides, 7a-l, was accomplished by S-substitution of 5-[(2-amino-1,3-thiazol-4-yl)methyl]-1,3,4-oxadiazol-2-thiol (3). The synthesis was initiated from ethyl 2-(2-amino-1,3-thiazol-4-yl)acetate (1) which was converted to corresponding hydrazide, 2, by hydrazine hydrate in methanol. The refluxing of hydrazide, 2, with carbon disulfide in basic medium, resulted in 5-[(2-amino-1,3-thiazol-4-yl)methyl]-1,3,4-oxadiazol-2-thiol (3). A series of electrophiles, 6a-l, was synthesized by stirring un/substituted anilines (4a-l) with 3-bromopropanoyl chloride (5) in a basic aqueous medium. Finally, the targeted compounds, 7a-l, were acquired by stirring 3 with newly synthesized electrophiles, 6a-l, in DMF using LiH as a base and an activator. The structures of these bi-heterocyclic propanamides were confirmed through spectroscopic techniques, such as IR, 1H-NMR, 13C-NMR, and EI-MS. These molecules were tested for their urease inhibitory potential, whereby, the whole series exhibited very promising activity against this enzyme. Their cytotoxic behavior was ascertained through hemolysis and it was observed that all these were less cytotoxic agents. The in-silico molecular docking analysis of these molecules was also in full agreement with their in-vitro enzyme inhibition data.
    Matched MeSH terms: Proton Magnetic Resonance Spectroscopy
  9. Optimization of microencapsulation process for self-healing polymeric material
    Then S, Gan SN, Noor Hayaty Abu Kasim
    Sains Malaysiana, 2011;40:1179-1186.
    A series of poly(urea-formaldehyde) (PUF) microcapsules filled with dicyclopentadiene (DCPD) was successfully prepared by in situ polymerization. The effect of diverse process parameters and ingredients on the morphology of the microcapsules was observed by SEM, optical microscopy (OM) and digital microscopy. Different techniques for the characterization of the chemical structure and the core content were considered such as FT-IR and 1H-NMR as well as the characterization of thermal properties by DSC. High yields of free flowing powder of spherical microcapsules were produced. The synthesized microcapsules can be incorporated into another polymeric host material. In the event the host material cracks due to excessive stress or strong impact, the microcapsules would rupture to release the DCPD, which could polymerize to repair the crack.
    Matched MeSH terms: Proton Magnetic Resonance Spectroscopy
  10. Fulltext PRELIMINARY STUDY OF 4-ARMS POLY(CAPROLACTONE) STAR- SHAPED POLYMER: SYNTHESIS AND CHARACTERIZATION
    Siti Hajar Ahmad Shariff, Mohamad Wafiuddin Ismail
    Journal of Academia Universiti Teknologi MARA Negeri Sembilan, 2021;9(1):127-138.
    MyJurnal
    Star-shaped polymers have vast potential in bioapplication due to their architecture. In this study, the suitability of ring opening polymerization (ROP) technique to synthesis star-shaped poly(caprolactone) and the thermal properties of the synthesized star-shaped polymers were demonstrated. The 4 -arm star- shaped of poly(caprolactone) (4s PCL) with -OH terminal and average molecular weight (Mn) of 5000, 10000, and 15000 g/mol were synthesized via ROP of ԑ-caprolactone (ԑ-CL) using a symmetric pentaerythritol (PET) as the core. Different molecular weights were obtained by using different ratios of ԑ-CL and PET in the presence of catalyst, stannous octoate (Sn(Oct)2). The FTIR spectra showed the presence of bands of methylene group of polymer repeating chain which confirm ROP of the ԑ- caprolactone. The average molecular weight (Mn) determined from proton nuclear magnetic resonance (1H NMR) analysis showed that all 4s PCL have approximately the same molecular weight as the theoretical values. All polymers obtained had high yield with >85%. Thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) analysis showed that there were no significance different in the thermal properties of the synthesized polymers. A single step degradation for all 4s PCL was observed and the crystallization melting point of the polymers was within the range of melting point of PCL.
    Matched MeSH terms: Proton Magnetic Resonance Spectroscopy
  11. Fulltext Pellet diameter of Ganoderma lucidum in a repeated-batch fermentation for the trio total production of biomass-exopolysaccharide-endopolysaccharide and its anti-oral cancer beta-glucan response
    Abdullah NR, Sharif F, Azizan NH, Hafidz IFM, Supramani S, Usuldin SRA, et al.
    AIMS Microbiol, 2020;6(4):379-400.
    PMID: 33364534 DOI: 10.3934/microbiol.2020023
    The pellet morphology and diameter range (DR) of Ganoderma lucidum were observed in a repeated-batch fermentation (RBF) for the trio total production of biomass, exopolysaccharide (EPS) and endopolysaccharide (ENS). Two factors were involved in RBF; broth replacement ratio (BRR: 60%, 75% and 90%) and broth replacement time point (BRTP: log, transition and stationary phase) in days. In RBF, 34.31 g/L of biomass favoured small-compact pellets with DR of 20.67 µm< d < 24.00 µm (75% BRR, day 11 of BRTP). EPS production of 4.34 g/L was prone to ovoid-starburst pellets with DR of 34.33 µm< d <35.67 µm (75% BRR, day 13 of BRTP). Meanwhile, the highest 2.43 g/L of ENS production favoured large-hollow pellets with DR of 34.00 µm< d < 38.67 µm (90% BRR, day 13 of BRTP). In addition, RBF successfully shortened the biomass-EPS-ENS fermentation period (31, 33 and 35 days) from batch to 5 days, in seven consecutive cycles of RBF. In a FTIR detection, β-glucan (BG) from EPS and ENS extracts were associated with β-glycosidic linkages (2925 cm-1, 1635 cm-1, 1077 cm-1, 920 cm-1 and 800 cm-1 wavelengths) with similar 1H NMR spectral behaviour (4.58, 3.87 and 3.81 ppm). Meanwhile, 4 mg/L of BG gave negative cytotoxic effects on normal gingival cell line (hGF) but induced antiproliferation (IC50 = 0.23 mg/mL) against cancerous oral Asian cellosaurus cell line (ORL-48). Together, this study proved that G. lucidum mycelial pellets could withstand seven cycles of long fermentation condition and possessed anti-oral cancer beta-glucan, which suits large-scale natural drug fermentation.
    Matched MeSH terms: Proton Magnetic Resonance Spectroscopy
  12. Penghasilan poliol minyak sawit olein secara hidrolisis selanjar dan berkelompok
    Darfizzi Derawi, Jumat Salimon
    Sains Malaysiana, 2013;42:1121-1129.
    Sebatian poliol minyak sawit olein (di-hidroksi-POo) (70% hasil) disintesis melalui pembukaan gelang oksirana minyak sawit olein terepoksida (EPOo) secara hidrolisis selanjar dan berkelompok. Hasil optimum pembukaan gelang oksirana (97.2%) bagi kedua-dua tindak balas selama 90 min (tindak balas selanjar) dan 75 min (tindak balas berkelompok) dengan menggunakan mangkin asid perklorik 3% v/wt. Spektrum transformasi Fourier inframerah (FTIR) di-hidroksi-POo menunjukkan kehadiran puncak lebar getaran regangan kumpulan hidroksil pada nombor gelombang 3429 cm-1, menunjukkan sebatian poliol telah berjaya dihasilkan. Spektrum resonan magnetik nukleus-karbon (13C-NMR) di-hidroksi-POo telah menunjukkan kehadiran puncak karbon yang terikat dengan kumpulan hidroksil (74.5 ppm). Spektrum resonan magnetik nukleus-proton (1H-NMR) di-hidroksi-POo telah menunjukkan kehadiran puncak proton yang terikat pada karbon poliol (3.4 ppm) dan proton pada kumpulan hidroksil (4.6 ppm). Kelikatan kinematik produk poliol (nilai hidroksil sebanyak 110.7 mgKOH/g minyak) adalah 1435.2 cSt (40oC) dan 55.2 cSt (100oC) dengan indeks kelikatan 78.
    Matched MeSH terms: Proton Magnetic Resonance Spectroscopy
  13. Pharmacometabolomics analysis of plasma to phenotype clopidogrel high on treatment platelets reactivity in coronary artery disease patients
    Amin AM, Sheau Chin L, Teh CH, Mostafa H, Mohamed Noor DA, Abdul Kader MASK, et al.
    Eur J Pharm Sci, 2018 May 30;117:351-361.
    PMID: 29526765 DOI: 10.1016/j.ejps.2018.03.011
    Dual antiplatelet therapy (DAPT) of clopidogrel and aspirin is crucial for coronary artery disease (CAD) patients undergoing percutaneous coronary intervention (PCI). However, some patients may endure clopidogrel high on treatment platelets reactivity (HTPR) which may cause thromboembolic events. Clopidogrel HTPR is multifactorial with some genetic and non-genetic factors contributing to it. We aimed to use nuclear magnetic resonance (1H NMR) pharmacometabolomics analysis of plasma to investigate this multifactorial and identify metabolic phenotypes and pathways associated with clopidogrel HTPR. Blood samples were collected from 71 CAD patients planned for interventional angiographic procedure (IAP) before the administration of clopidogrel 600 mg loading dose (LD) and 6 h after the LD. Platelets function testing was done 6 h post-LD using VerifyNow® P2Y12 assay. Pre-dose and post-dose plasma samples were analysed using 1H NMR. Multivariate statistical analysis was used to indicate the discriminating metabolites. Two metabotypes, each with 34 metabolites (pre-dose and post-dose) were associated with clopidogrel HTPR. Pathway analysis of these metabotypes revealed that aminoacyl-tRNA biosynthesis, nitrogen metabolism and glycine-serine-threonine metabolism are the most perturbed metabolic pathways associated with clopidogrel HTPR. Furthermore, the identified biomarkers indicated that clopidogrel HTPR is multifactorial where the metabolic phenotypes of insulin resistance, type two diabetes mellitus, obesity, gut-microbiota and heart failure are associated with it. Pharmacometabolomics analysis of plasma revealed new insights on the implicated metabolic pathways and the predisposing factors of clopidogrel HTPR.
    Matched MeSH terms: Proton Magnetic Resonance Spectroscopy*
  14. Plasma and urine metabolite profiling reveals the protective effect of Clinacanthus nutans in an ovalbumin-induced anaphylaxis model: 1H-NMR metabolomics approach
    Khoo LW, Audrey Kow SF, Maulidiani M, Lee MT, Tan CP, Shaari K, et al.
    J Pharm Biomed Anal, 2018 Sep 05;158:438-450.
    PMID: 29957507 DOI: 10.1016/j.jpba.2018.06.038
    The present study sought to identify the key biomarkers and pathways involved in the induction of allergic sensitization to ovalbumin and to elucidate the potential anti-anaphylaxis property of Clinacanthus nutans (Burm. f.) Lindau water leaf extract, a Southeast Asia herb in an in vivo ovalbumin-induced active systemic anaphylaxis model evaluated by 1H-NMR metabolomics. The results revealed that carbohydrate metabolism (glucose, myo-inositol, galactarate) and lipid metabolism (glycerol, choline, sn-glycero-3-phosphocholine) are the key requisites for the induction of anaphylaxis reaction. Sensitized rats treated with 2000 mg/kg bw C. nutans extract before ovalbumin challenge showed a positive correlation with the normal group and was negatively related to the induced group. Further 1H-NMR analysis in complement with Kyoto Encyclopedia of Genes and Genomes (KEGG) reveals the protective effect of C. nutans extract against ovalbumin-induced anaphylaxis through the down-regulation of lipid metabolism (choline, sn-glycero-3-phosphocholine), carbohydrate and signal transduction system (glucose, myo-inositol, galactarate) and up-regulation of citrate cycle intermediates (citrate, 2-oxoglutarate, succinate), propanoate metabolism (1,2-propanediol), amino acid metabolism (betaine, N,N-dimethylglycine, methylguanidine, valine) and nucleotide metabolism (malonate, allantoin). In summary, this study reports for the first time, C. nutans water extract is a potential anti-anaphylactic agent and 1H-NMR metabolomics is a great alternative analytical tool to explicate the mechanism of action of anaphylaxis.
    Matched MeSH terms: Proton Magnetic Resonance Spectroscopy/instrumentation; Proton Magnetic Resonance Spectroscopy/methods*
  15. Fulltext Potentially Bioactive Metabolites from Pineapple Waste Extracts and Their Antioxidant and α-Glucosidase Inhibitory Activities by 1H NMR
    Azizan A, Xin LA, Abdul Hamid NA, Maulidiani M, Mediani A, Abdul Ghafar SZ, et al.
    Foods, 2020 Feb 11;9(2).
    PMID: 32053982 DOI: 10.3390/foods9020173
    Pineapple (Ananascomosus) waste is a promising source of metabolites for therapeutics, functional foods, and cosmeceutical applications. This study strives to characterize the complete metabolite profiles of a variety of MD2 pineapple waste extracts. Metabolomics strategies were utilized to identify bioactive metabolites of this variety prepared with different solvent ratios. Each pineapple waste extract was first screened for total phenolic content, 2,2-diphenyl-1-picrylhydrazyl free radical scavenging, nitric oxide scavenging, and α-glucosidase inhibitory activities. The highest TPC was found in all samples of the peel, crown, and core extracted using a 50% ethanol ratio, even though the results were fairly significant than those obtained for other ethanol ratios. Additionally, crown extracted with a 100% ethanol ratio demonstrated the highest potency in DPPH and NO scavenging activity, with IC50 values of 296.31 and 338.52 µg/mL, respectively. Peel extracted with 100% ethanol exhibited the highest α-glucosidase inhibitory activity with an IC50 value of 92.95 µg/mL. Then, the extracts were analyzed and the data from 1H NMR were processed using multivariate data analysis. A partial least squares and correlogram plot suggested that 3-methylglutaric acid, threonine, valine, and α-linolenic acid were the main contributors to the antioxidant activities, whereas epicatechin was responsible for the α-glucosidase inhibitory activity. Relative quantification further supported that 100% crown extract was among the extracts that possessed the most abundant potential metabolites. The present study demonstrated that the crown and peel parts of MD2 pineapple extracted with 100% ethanol are potentially natural sources of antioxidants and α-glucosidase inhibitors, respectively.
    Matched MeSH terms: Proton Magnetic Resonance Spectroscopy
  16. Fulltext Prospective role of mitochondrial apoptotic pathway in mediating GMG-ITC to reduce cytotoxicity in H2O2-induced oxidative stress in differentiated SH-SY5Y cells
    Jaafaru MS, Nordin N, Rosli R, Shaari K, Bako HY, Noor NM, et al.
    Biomed Pharmacother, 2019 Nov;119:109445.
    PMID: 31541852 DOI: 10.1016/j.biopha.2019.109445
    The antioxidant and neuroprotective activity of Glucomoringin isothiocyanate (GMG-ITC) have been reported in in vivo and in vitro models of neurodegenerative diseases. However, its neuroprotective role via mitochondrial-dependent pathway in a noxious environment remains unknown. The main objective of the present study was to unveil the mitochondrial apoptotic genes' profile and prospectively link with neuroprotective activity of GMG-ITC through its ROS scavenging. The results showed that pre-treatment of differentiated SH-SY5Y cells with 1.25 μg/mL purified isolated GMG-ITC, significantly reduced reactive oxygen species (ROS) production level, compared to H2O2 control group, as evidenced by flow cytometry-based evaluation of ROS generation. Presence of GMG-ITC prior to development of oxidative stress condition, downregulated the expression of cyt-c, p53, Apaf-1, Bax, CASP3, CASP8 and CASP9 genes with concurrent upregulation of Bcl-2 gene in mitochondrial apoptotic signalling pathway. Protein Multiplex revealed significant decreased in cyt-c, p53, Apaf-1, Bax, CASP8 and CASP9 due to GMG-ITC pre-treatment in oxidative stress condition. The present findings speculated that pre-treatment with GMG-ITC may alleviate oxidative stress condition in neuronal cells by reducing ROS production level and protect the cells against apoptosis via neurodegenerative disease potential pathways.
    Matched MeSH terms: Proton Magnetic Resonance Spectroscopy
  17. Recovery of cellulose fibers from oil palm empty fruit bunch for pulp and paper using green delignification approach
    Yiin CL, Ho S, Yusup S, Quitain AT, Chan YH, Loy ACM, et al.
    Bioresour Technol, 2019 Oct;290:121797.
    PMID: 31327691 DOI: 10.1016/j.biortech.2019.121797
    The aim of this work was to recover the cellulose fibers from EFB using low-transition-temperature-mixtures (LTTMs) as a green delignification approach. The hydrogen bonding of LTTMs observed in 1H NMR tends to disrupt the three-dimensional structure of lignin and further remove the lignin from EFB. Delignification process of EFB strands and EFB powder were performed using standard l-malic acid and cactus malic acid-LTTMs. The recovered cactus malic acid-LTTMs showed higher glucose concentration of 8.07 mg/mL than the recovered l-malic acid LTTMs (4.15 mg/mL). This implies that cactus malic acid-LTTMs had higher delignification efficiency which led to higher amount of cellulose hydrolyzed into glucose. The cactus malic acid-LTTMs-delignified EFB was the most feasible fibers for making paper due to its lowest kappa number of 69.84. The LTTMs-delignified EFB has great potential to be used for making specialty papers in pulp and paper industry.
    Matched MeSH terms: Proton Magnetic Resonance Spectroscopy
  18. Report - Synthesis of new antibacterial agents encompassing tosyl, piperidine, propanamide and 1,3,4-oxadiazole functionalities
    Sattar A, Aziz-Ur-Rehman -, Abbasi MA, Siddiqui SZ, Rasool S, Ali Shah SA
    Pak J Pharm Sci, 2020 Jul;33(4):1697-1705.
    PMID: 33583804
    A series of propanamide compounds 6a-l was derived by N-substitution reactions, encompassing tosyl, piperidine and 1,3,4-oxadiazole moieties. The intended array of compounds 6a-l was afforded by a series of five steps reaction scheme. 1-Tosylpiperidin-4-carboxylate (1) was synthesized by the reaction of tosyl chloride (a) with ethyl isonipecotate (b) under mild basic conditions. Compound 1 was subjected to nucleophillic substitution by hydrazine to synthesize 1-tosylpiperidin-4-carbohydrazide (2). The compound, 5-(1-tosylpiperidin-4-yl)-1,3,4-oxadiazole-2-thiol (3) was synthesized by intermolecular cyclization of compound 2 by CS2 under strong basic conditions. The target compounds, 6a-l, were finally synthesized from 3 by reacting with different electrophiles, 5a-l, in an aprotic polar solvent with sodium hydride as an activator. The different propanamoyl electrophiles, 5a-l, were synthesized by the reaction of different aromatic and aliphatic amines, 4a-l, with 3-bromopropionyl chloride under mild basic conditions. The structural elucidation was carried out using modern spectroscopic techniques including IR, 1H-NMR and EI-MS. The antibacterial potential of synthesized compounds was assessed against five bacterial strains. Compounds 6a, 6c, 6d, 6e and 6f were found to be potent antibacterial agents.
    Matched MeSH terms: Proton Magnetic Resonance Spectroscopy
  19. Revealing metabolic and biochemical variations via 1H NMR metabolomics in streptozotocin-nicotinamide-induced diabetic rats treated with metformin
    Zolkeflee NKZ, Wong PL, Maulidiani M, Ramli NS, Azlan A, Mediani A, et al.
    Biochem Biophys Res Commun, 2024 May 14;708:149778.
    PMID: 38507867 DOI: 10.1016/j.bbrc.2024.149778
    The increasing prevalence of lean diabetes has prompted the generation of animal models that mimic metabolic disease in humans. This study aimed to determine the optimum streptozotocin-nicotinamide (STZ-NA) dosage ratio to elicit lean diabetic features in a rat model. It also used a proton nuclear magnetic resonance (1H NMR) urinary metabolomics approach to identify the metabolic effect of metformin treatment on this novel rat model. Three different STZ-NA dosage regimens (by body weight: Group A: 110 mg/kg NA and 45 mg/kg STZ; Group B: 180 mg/kg NA and 65 mg/kg STZ and Group C: 120 mg/kg NA and 60 mg/kg STZ) were administered to Sprague-Dawley rats along with oral metformin. Group A diabetic rats (A-DC) showed favorable serum biochemical analyses and a more positive response toward oral metformin administration relative to the other STZ-NA dosage ratio groups. Orthogonal partial least squares-discriminant analysis (OPLS-DA) revealed that glucose, citrate, pyruvate, hippurate, and methylnicotinamide differentiating the OPLS-DA of A-MTF rats (Group A diabetic rats treated with metformin) and A-DC model rats. Subsequent metabolic pathway analyses revealed that metformin treatment was associated with improvement in dysfunctions caused by STZ-NA induction, including carbohydrate metabolism, cofactor metabolism, and vitamin and amino acid metabolism. In conclusion, our results identify the best STZ-NA dosage ratio for a rat model to exhibit lean type 2 diabetic features with optimum sensitivity to metformin treatment. The data presented here could be informative to improve our understanding of non-obese diabetes in humans through the identification of possible activated metabolic pathways in the STZ-NA-induced diabetic rats model.
    Matched MeSH terms: Proton Magnetic Resonance Spectroscopy
  20. Self-assembly of a robust hydrogen-bonded octylphosphonate network on cesium lead bromide perovskite nanocrystals for light-emitting diodes
    Brown AAM, Hooper TJN, Veldhuis SA, Chin XY, Bruno A, Vashishtha P, et al.
    Nanoscale, 2019 Jul 07;11(25):12370-12380.
    PMID: 31215940 DOI: 10.1039/c9nr02566a
    We report the self-assembly of an extensive inter-ligand hydrogen-bonding network of octylphosphonates on the surface of cesium lead bromide nanocrystals (CsPbBr3 NCs). The post-synthetic addition of octylphosphonic acid to oleic acid/oleylamine-capped CsPbBr3 NCs promoted the attachment of octylphosphonate to the NC surface, while the remaining oleylammonium ligands maintained the high dispersability of the NCs in non-polar solvent. Through powerful 2D solid-state 31P-1H NMR, we demonstrated that an ethyl acetate/acetonitrile purification regime was crucial for initiating the self-assembly of extensive octylphosphonate chains. Octylphosphonate ligands were found to preferentially bind in a monodentate mode through P-O-, leaving polar P[double bond, length as m-dash]O and P-OH groups free to form inter-ligand hydrogen bonds. The octylphosphonate ligand network strongly passivated the nanocrystal surface, yielding a fully-purified CsPbBr3 NC ink with PLQY of 62%, over 3 times higher than untreated NCs. We translated this to LED devices, achieving maximum external quantum efficiency and luminance of 7.74% and 1022 cd m-2 with OPA treatment, as opposed to 3.59% and 229 cd m-2 for untreated CsPbBr3 NCs. This represents one of the highest efficiency LEDs obtained for all-inorganic CsPbBr3 NCs, accomplished through simple, effective passivation and purification processes. The robust binding of octylphosphonates to the perovskite lattice, and specifically their ability to interlink through hydrogen bonding, offers a promising passivation approach which could potentially be beneficial across a breadth of halide perovskite optoelectronic applications.
    Matched MeSH terms: Proton Magnetic Resonance Spectroscopy
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