Displaying publications 21 - 40 of 120 in total

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  1. Contreras-Jodar A, Nayan NH, Hamzaoui S, Caja G, Salama AAK
    PLoS One, 2019;14(2):e0202457.
    PMID: 30735497 DOI: 10.1371/journal.pone.0202457
    The aim of the study is to identify the candidate biomarkers of heat stress (HS) in the urine of lactating dairy goats through the application of proton Nuclear Magnetic Resonance (1H NMR)-based metabolomic analysis. Dairy does (n = 16) in mid-lactation were submitted to thermal neutral (TN; indoors; 15 to 20°C; 40 to 45% humidity) or HS (climatic chamber; 37°C day, 30°C night; 40% humidity) conditions according to a crossover design (2 periods of 21 days). Thermophysiological traits and lactational performances were recorded and milk composition analyzed during each period. Urine samples were collected at day 15 of each period for 1H NMR spectroscopy analysis. Principal component analysis (PCA) and partial least square-discriminant analysis (PLS-DA) assessment with cross validation were used to identify the goat urinary metabolome from the Human Metabolome Data Base. HS increased rectal temperature (1.2°C), respiratory rate (3.5-fold) and water intake (74%), but decreased feed intake (35%) and body weight (5%) of the lactating does. No differences were detected in milk yield, but HS decreased the milk contents of fat (9%), protein (16%) and lactose (5%). Metabolomics allowed separating TN and HS urinary clusters by PLS-DA. Most discriminating metabolites were hippurate and other phenylalanine (Phe) derivative compounds, which increased in HS vs. TN does. The greater excretion of these gut-derived toxic compounds indicated that HS induced a harmful gastrointestinal microbiota overgrowth, which should have sequestered aromatic amino acids for their metabolism and decreased the synthesis of neurotransmitters and thyroid hormones, with a negative impact on milk yield and composition. In conclusion, HS markedly changed the thermophysiological traits and lactational performances of dairy goats, which were translated into their urinary metabolomic profile through the presence of gut-derived toxic compounds. Hippurate and other Phe-derivative compounds are suggested as urinary biomarkers to detect heat-stressed dairy animals in practice.
    Matched MeSH terms: Protons
  2. Norasikin Ab Azis, Mohd Saleh Ahmad Kamal, Zurain Radjeni, Ahmed Mediani, Renu Agarwal
    MyJurnal
    Introduction: This study examined the association of losartan induced changes in urinary
    metabolomic profile with the changes in blood pressure (BP) and renin-angiotensinaldosterone system (RAAS) in spontaneously hypertensive rats (SHR). Methods: Male SHR
    were administered with either 0.5 mL of distilled water (control group, n=6) or 10 mg.kg-1 of
    losartan (group 2, n=6) daily by oral gavage for 4 weeks. Body weight, BP, food and water
    intake were measured weekly. At week 4, urine was collected for urinary electrolyte analysis
    and metabolite profiling, after which the animals were euthanised by decapitation and blood
    was collected for analysis of components of RAAS and electrolyte concentrations. Urine
    metabolite profile of SHR was determined using proton nuclear magnetic resonance (
    1H-NMR)
    spectrometry combined with multivariate data analysis. Results: At week 4, losartan-treated
    SHR had significantly lower BP than non-treated SHR. There were no differences in water
    and food intake, body weight, serum and urinary electrolyte concentrations or in their urinary
    excretions between the two groups. No differences were evident in the components of RAAS
    except that the angiotensinogen level was significantly higher in losartan-treated SHR
    compared to non-treated SHR. Orthogonal partial least squares discriminant analysis (OPLSDA) showed clear separation of urinary metabolites between control and losartan-treated
    SHR. Losartan-treated SHR group was separated from the control group by changes in the
    intermediates involved in glycine, serine and threonine metabolism. Conclusion:
    Antihypertensive effect of losartan in SHR seems to be associated with changes in urinary
    metabolite profile, particularly involving the metabolism of glycine, serine and threonine.
    Matched MeSH terms: Protons
  3. 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: Protons
  4. Brela MZ, Wójcik MJ, Witek ŁJ, Boczar M, Wrona E, Hashim R, et al.
    J Phys Chem B, 2016 04 28;120(16):3854-62.
    PMID: 27045959 DOI: 10.1021/acs.jpcb.6b01601
    In this study, the proton dynamics of hydrogen bonds for two forms of crystalline aspirin was investigated by the Born-Oppenheimer molecular dynamics (BOMD) method. Analysis of the geometrical parameters of hydrogen bonds using BOMD reveals significant differences in hydrogen bonding between the two crystalline forms of aspirin, Form I and Form II. Analysis of the trajectory for Form I shows spontaneous proton transfer in cyclic dimers, which is absent in Form II. Quantization of the O-H stretching modes allows a detailed discussion on the strength of hydrogen-bonding interactions. The focal point of our study is examination of the hydrogen bond characteristics in the crystal structure and clarification of the influence of hydrogen bonding on the presence of the two crystalline forms of aspirin. In the BOMD method, thermal motions were taken into account. Solving the Schrödinger equation for the snapshots of 2D proton potentials, extracted from MD, gives the best agreement with IR spectra. The character of medium-strong hydrogen bonds in Form I of aspirin was compared with that of weaker hydrogen bonds in aspirin Form II. Two proton minima are present in the potential function for the hydrogen bonds in Form I. The band contours, calculated by using one- and two-dimensional O-H quantization, reflect the differences in the hydrogen bond strengths between the two crystalline forms of aspirin, as well as the strong hydrogen bonding in the cyclic dimers of Form I and the medium-strong hydrogen bonding in Form II.
    Matched MeSH terms: Protons*
  5. Oon YS, Ong SA, Ho LN, Wong YS, Oon YL, Lehl HK, et al.
    J Hazard Mater, 2017 Mar 05;325:170-177.
    PMID: 27931001 DOI: 10.1016/j.jhazmat.2016.11.074
    Monoazo and diazo dyes [New coccine (NC), Acid orange 7 (AO7), Reactive red 120 (RR120) and Reactive green 19 (RG19)] were employed as electron acceptors in the abiotic cathode of microbial fuel cell. The electrons and protons generated from microbial organic oxidation at the anode which were utilized for electrochemical azo dye reduction at the cathodic chamber was successfully demonstrated. When NC was employed as the electron acceptor, the chemical oxygen demand (COD) removal and dye decolourisation efficiencies obtained at the anodic and cathodic chamber were 73±3% and 95.1±1.1%, respectively. This study demonstrated that the decolourisation rates of monoazo dyes were ∼50% higher than diazo dyes. The maximum power density in relation to NC decolourisation was 20.64mW/m2, corresponding to current density of 120.24mA/m2. The decolourisation rate and power output of different azo dyes were in the order of NC>AO7>RR120>RG19. The findings revealed that the structure of dye influenced the decolourisation and power performance of MFC. Azo dye with electron-withdrawing group at para substituent to azo bond would draw electrons from azo bond; hence the azo dye became more electrophilic and more favourable for dye reduction.
    Matched MeSH terms: Protons
  6. Kakkar S, Kumar S, Lim SM, Ramasamy K, Mani V, Shah SAA, et al.
    Chem Cent J, 2018 Dec 04;12(1):130.
    PMID: 30515643 DOI: 10.1186/s13065-018-0499-x
    BACKGROUND: In view of wide range of biological activities of oxazole, a new series of oxazole analogues was synthesized and its chemical structures were confirmed by spectral data (Proton/Carbon-NMR, IR, MS etc.). The synthesized oxazole derivatives were screened for their antimicrobial and antiproliferative activities.

    RESULTS AND DISCUSSION: The antimicrobial activity was performed against selected fungal and bacterial strains using tube dilution method. The antiproliferative potential was evaluated against human colorectal carcinoma (HCT116) and oestrogen- positive human breast carcinoma (MCF7) cancer cell lines using Sulforhodamine B assay and, results were compared to standard drugs, 5-fluorouracil and tamoxifen, respectively.

    CONCLUSION: The performed antimicrobial activity indicated that compounds 3, 5, 6, 8 and 14 showed promising activity against selected microbial species. Antiproliferative screening found compound 14 to be the most potent compound against HCT116 (IC50 = 71.8 µM), whereas Compound 6 was the most potent against MCF7 (IC50 = 74.1 µM). Further, the molecular docking study has been carried to find out the interaction between active oxazole compounds with CDK8 (HCT116) and ER-α (MCF7) proteins indicated that compound 14 and 6 showed good dock score with better potency within the ATP binding pocket and may be used as a lead for rational drug designing of the anticancer molecule.

    Matched MeSH terms: Protons
  7. Aziz SB, Abdulwahid RT, Hamsan MH, Brza MA, Abdullah RM, Kadir MFZ, et al.
    Molecules, 2019 Sep 27;24(19).
    PMID: 31569650 DOI: 10.3390/molecules24193508
    In this report, a facile solution casting technique was used to fabricate polymer blend electrolytes of chitosan (CS):poly (ethylene oxide) (PEO):NH4SCN with high electrochemical stability (2.43V). Fourier transform infrared (FTIR) spectroscopy was used to investigate the polymer electrolyte formation. For the electrochemical property analysis, cyclic voltammetry (CV), linear sweep voltammetry (LSV), and electrochemical impedance spectroscopy (EIS) techniques were carried out. Referring to the FTIR spectra, a complex formation between the added salt and CS:PEO was deduced by considering the decreasing and shifting of FTIR bands intensity in terms of functional groups. The CS:PEO:NH4SCN electrolyte was found to be electrochemically stable as the applied voltage linearly swept up to 2.43V. The cyclic voltammogram has presented a wide potential window without showing any sign of redox peaks on the electrode surface. The proved mechanisms of charge storage in these fabricated systems were found to be double layer charging. The EIS analysis showed the existence of bulk resistance, wherein the semicircle diameter decreased with increasing salt concentration. The calculated maximum DC conductivity value was observed to be 2.11 × 10-4 S/cm for CS:PEO incorporated with 40 wt% of NH4SCN salt. The charged species in CS:PEO:NH4SCN electrolytes were considered to be predominantly ionic in nature. This was verified from transference number analysis (TNM), in which ion and electron transference numbers were found to be tion = 0.954 and tel = 0.045, respectively. The results obtained for both ion transference number and DC conductivity implied the possibility of fabricating electrolytes for electrochemical double layer capacitor (EDLC) device application. The specific capacitance of the fabricated EDLC was obtained from the area under the curve of the CV plot.
    Matched MeSH terms: Protons*
  8. Kadhum AAH, Mohamad AB, Hammed LA, Al-Amiery AA, San NH, Musa AY
    Materials (Basel), 2014 Jun 05;7(6):4335-4348.
    PMID: 28788680 DOI: 10.3390/ma7064335
    A new coumarin derivative, N,N'-((2E,2'E)-2,2'-(1,4-phenylenebis (methanylylidene))bis(hydrazinecarbonothioyl))bis(2-oxo-2H-chromene-3-carboxamide) PMBH, was synthesized and its chemical structure was elucidated and confirmed using spectroscopic techniques (Infrared spectroscopy IR, Proton nuclear magnetic resonance, (1)H-NMR and carbon-13 nuclear magnetic resonance (13)C-NMR). The corrosion inhibition effect of PMBH on mild steel in 1.0 M HCl was investigated using corrosion potential (ECORR), potentiodynamic polarization, electrochemical impedance spectroscopy (EIS), and electrochemical frequency modulation (EFM) measurements. The obtained results indicated that PMBH has promising inhibitive effects on the corrosion of mild steel in 1.0 M HCl across all of the conditions examined. Scanning electron microscopy (SEM) was used to investigate the morphology of the mild steel before and after immersion in 1.0 M HCl solution containing 0.5 mM of PMBH. Surface analysis revealed improvement of corrosion resistance in presence of PMBH.
    Matched MeSH terms: Protons
  9. Tabbakh F, Hosmane NS, Tajudin SM, Ghorashi AH, Morshedian N
    Sci Rep, 2022 Oct 18;12(1):17404.
    PMID: 36258012 DOI: 10.1038/s41598-022-22429-0
    There are two major problems in proton therapy. (1) In comparison with the gamma-ray therapy, proton therapy has only ~ 10% greater biological effectiveness, and (2) the risk of the secondary neutrons in proton therapy is another unsolved problem. In this report, the increase of biological effectiveness in proton therapy has been evaluated with better performance than 11B in the presence of two proposed nanomaterials of 157GdF4 and 157Gd doped carbon with the thermal neutron reduction due to the presence of 157Gd isotope. The present study is based on the microanalysis calculations using GEANT4 Monte Carlo tool and GEANT4-DNA package for the strand breaks measurement. It was found that the proposed method will increase the effectiveness corresponding to the alpha particles by more than 100% and also, potentially will decrease the thermal neutrons fluence, significantly. Also, in this work, a discussion is presented on a significant contribution of the secondary alpha particles in total effectiveness in proton therapy.
    Matched MeSH terms: Protons
  10. Khairi M, Zakaria F, Supar R, Mohd Z
    Med J Malaysia, 2024 Mar;79(Suppl 1):74-81.
    PMID: 38555889
    INTRODUCTION: Motion and pulsation artifacts are the most prominent types of artifacts in Magnetic Resonance Imaging (MRI) of the shoulder. Therefore, this study examined the Periodically Rotating Overlapping Parallel Lines with Enhanced Reconstruction (PROPELLER) technique with small flex coil (SFC) and dedicated shoulder coil (DSC) for the reduction of motion and pulsation artifacts. The signalto- noise ratio (SNR) and contrast-to-noise ratio (CNR) of the standard proton density fat saturation (PDFS) pulse sequence and the PROPELLER proton density fat saturation (PROPELLER PDFS) pulse sequence were also evaluated.

    MATERIALS AND METHODS: Eighteen (18) participants who met the inclusion and exclusion criteria were scanned using a standard non-contrast MRI shoulder protocol including the PDFS pulse sequence and the PROPELLER PDFS pulse sequence using a small flex coil and a dedicated shoulder coil. Two experienced musculoskeletal (MSK) radiologists evaluated and graded the presence of artifacts on the MR images and the SNR and CNR were measured quantitatively.

    RESULTS: The non-parametric Wilcoxon Signed Rank test revealed a significant reduction in motion and pulsation artifacts between the PROPELLER PDFS pulse sequence and the standard PDFS pulse sequence. In addition, the nonparametric Mann-Whitney U test revealed that the mean rank of SNR for the standard sequence was statistically significant when compared to the PROPELLER sequence for both coil types. The CNR of the PROPELLER sequence was statistically significant between fat-fluid, bone-fluid, bonetendon, bone-muscle, and muscle-fluid when using SFC and DSC.

    CONCLUSION: This study proved that the PROPELLER-PDFS pulse sequence effectively eliminates motion and pulsation artifacts, regardless of the coils utilised. The PROPELLERPDFS pulse sequence can therefore be implemented into the standard MRI shoulder procedure.

    Matched MeSH terms: Protons*
  11. Wun FML, Muhd Hafizi Zainal, Syahidah Mohd Tahir, Ishak B. Ahmad, Mohammad B. Kassim
    Sains Malaysiana, 2018;47:923-929.
    The presence of two different chromophores in benzothiazole molecule namely benzothiazole and aromatic rings lead to
    interesting chemical and biological properties that attract more researches on the compounds. Three new benzothiazolylbenzoythiourea
    compounds namely 1-(1,3-benzothiazol-2-yl)-3-(benzoylthiourea) (BBT), 1-(1,3-benzothiazol-2-yl)-3-
    (4-chlorobenzoylthiourea) (BBT-4Cl) and 1-(1,3-benzothiazol-2-yl)-3-(4-methoxybenzoylthiourea) (BBT-4OCH3
    ) with
    different electron withdrawing substituents (R) at the para positions on the benzene ring of benzoylthiourea ring have
    been synthesized from the reaction of R-benzoyl isothiocyanate (R= H, Cl, and OCH3
    ) and 2-aminobenzothiazole. The
    compounds were characterized by spectroscopic techniques (infrared, 1
    H proton NMR and UV-Vis). The IR spectra showed
    the frequency signals of n (C=O), n (C=S), n (N-H) at 1664-1673, 1238-1249 and 3031-3055 cm-1, respectively. The 1
    H
    proton NMR spectra showed the presence of N-H amine and amide signals in the region of (12.14-12.35) and (14.17-14.43)
    ppm, respectively. The proton signals of the two benzothiazole and benzoylthiourea moieties appear at 7.08-8.16 ppm.
    A theoretical study based on Density Functional Theory (DFT) and Time-Dependent (TD) DFT was conducted to optimize
    the geometrical structure and investigate the electronic properties of title compounds. The highest occupied molecular
    orbital (HOMO) was found on the benzothiazole moiety; while, the lowest-unoccupied molecular orbital (LUMO) was
    located at the benzoylthiourea fragment. The DFT optimized structures possessed an intramolecular hydrogen bonding
    and the types of para substituents used influenced the properties of hydrogen bonding.
    Matched MeSH terms: Protons
  12. Siti Hajar Ahmad Shariff, Mohamad Wafiuddin Ismail
    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: Protons
  13. Yahya N, Manan HA
    Support Care Cancer, 2021 Jun;29(6):3035-3047.
    PMID: 33040284 DOI: 10.1007/s00520-020-05808-z
    BACKGROUND: Proton therapy (PT), frequently utilised to treat paediatric brain tumour (PBT) patients, eliminates exit dose and minimises dose to healthy tissues that theoretically can mitigate treatment-related effects including cognitive deficits. As clinical outcome data are emerging, we aimed to systematically review current evidence of cognitive changes following PT of PBT.

    MATERIALS AND METHODS: We searched PubMed and Scopus electronic databases to identify eligible reports on cognitive changes following PT of PBT according to PRISMA guidelines. Reports were extracted for information on demographics and cognitive outcomes. Then, they were systematically reviewed based on three themes: (1) comparison with photon therapy, (2) comparison with baseline cognitive measures, to population normative mean or radiotherapy-naïve PBT patients and (3) effects of dose distribution to cognition.

    RESULTS: Thirteen reports (median size (range): 70 (12-144)) were included. Four reports compared the cognitive outcome between PBT patients treated with proton to photon therapy and nine compared with baseline/normative mean/radiotherapy naïve from which two reported the effects of dose distribution. Reports found significantly poorer cognitive outcome among patients treated with photon therapy compared with proton therapy especially in general cognition and working memory. Craniospinal irradiation (CSI) was consistently associated with poorer cognitive outcome while focal therapy was associated with minor cognitive change/difference. In limited reports available, higher doses to the hippocampus and temporal lobes were implicated to larger cognitive change.

    CONCLUSION: Available evidence suggests that PT causes less cognitive deficits compared with photon therapy. Children who underwent focal therapy with proton were consistently shown to have low risk of cognitive deficit suggesting the need for future studies to separate them from CSI. Evidence on the effect of dose distribution to cognition in PT is yet to mature.

    Matched MeSH terms: Protons
  14. Zetty Shafiqa Othman, Nurul Huda Abd Karim, Saiful Irwan Zubairi, Nur Hasyareeda Hassan, Mamoru Koketsu
    Sains Malaysiana, 2018;47:1473-1482.
    [BMIM]OTf and alcohol-based DES combination with a selected organic solvent (acetone and acetonitrile) have
    been proven to efficiently extracting rotenone (isoflavonoid biopesticide) compound compared to individual organic
    solvents. Their efficiency builds up interest to study the solvent-solute interaction that occurs between both selected
    solvent systems with rotenone. The interaction study was analyzed using FTIR, 1D-NMR and 2D- NMR (NOESY, HMBC).
    Correlation portrayed by NOESY and HMBC of [BMIM]OTf - standard rotenone mixture predicted probable hydrogen
    bonding between the oxygen of rotenone with acidic proton C2-H of [BMIM]OTf. While for the alcohol-based DESrotenone
    mixture, the correlation shows probable interaction to occur between methyl and methoxy group rotenone
    with the hydroxyl group of 1,4-butanediol. In conclusion, potential hydrogen bonding that occurs between solvent
    and solute aid towards the solvent efficiency in extracting rotenone compound while emphasizing on the low cost and
    green mediated solvent systems.
    Matched MeSH terms: Protons
  15. Noviany N, Samadi A, Yuliyan N, Hadi S, Aziz M, Purwitasari N, et al.
    Phytochem Lett, 2020 Feb;35:211-215.
    PMID: 32863985 DOI: 10.1016/j.phytol.2019.12.008
    A new 2-arylbenzofuran, sesbagrandiflorain C (1), together with four known compounds, 2-(3,4-dihydroxy-2-methoxyphenyl)-4-hydroxy-6-methoxybenzofuran-3-carbaldehyde (2), 2-(4-hydroxy-2-methoxyphenyl)-5,6-dimethoxybenzofuran-3-carboxaldehyde (3), sesbagrandiflorain A (4) and sesbagrandiflorain B (5), have been isolated from the stem bark of an Indonesian plant, Sesbania grandiflora (L.) Pers. The chemical structure of compound 1 was elucidated by UV, IR, MS, and NMR spectroscopic techniques. The proton and carbon NMR resonances of 1 were also compared with the predicted chemical shifts obtained from DFT quantum mechanical calculations with Gaussian. None of the compounds showed antibacterial activity against Bacillus subtilis, Escherichia coli, Mycobacterium smegmatis, Pseudomonas aeruginosa, and Staphylococcus aureus in an agar diffusion assay. However, sesbagrandiflorains A (4) and B (5) exhibited moderate activity against Mycobacterium tuberculosis H37Rv. In addition, compounds 1 - 5 have moderate cytotoxicity against HeLa, HepG2, and MCF-7 cancer cell lines.
    Matched MeSH terms: Protons
  16. 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: Protons
  17. Salehmin MNI, Hil Me MF, Daud WRW, Mohd Yasin NH, Abu Bakar MH, Sulong AB, et al.
    Sci Total Environ, 2023 Jan 10;855:158527.
    PMID: 36096221 DOI: 10.1016/j.scitotenv.2022.158527
    Microbial electrodialysis cells (MEDCs) offer simultaneous wastewater treatment, water desalination, and hydrogen production. In a conventional design of MEDCs, the overall performance is retarded by the accumulation of protons on the anode due to the integration of an anion exchange membrane (AEM). The accumulation of protons reduces the anolyte pH to become acidic, affecting the microbial viability and thus limiting the charge carrier needed for the cathodic reaction. This study has modified the conventional MEDC with an internal proton migration pathway, known as the internal proton migration pathway-MEDC (IP-MEDC). Simulation tests under abiotic conditions demonstrated that the pH changes in the anolyte and catholyte of IP-MEDC were smaller than the pH changes in the anolyte and catholyte without the proton pathways. Under biotic conditions, the performance of the IP-MEDC agreed well with the simulation test, showing a significantly higher chemical oxygen demand (COD) removal rate, desalination rate, and hydrogen production than without the migration pathway. This result is supported by the lowest charge transfer resistance shown by EIS analysis and the abundance of microbes on the bioanode through field emission scanning electron microscopy (FESEM) observation. However, hydrogen production was diminished in the second-fed batch cycle, presumably due to the active diffusion of high Cl¯ concentrations from desalination to the anode chamber, which was detrimental to microbial growth. Enlarging the anode volume by threefold improved the COD removal rate and hydrogen production rate by 1.7- and 3.4-fold, respectively, owing to the dilution effect of Cl¯ in the anode. This implied that the dilution effect satisfies both the microbial viability and conductivity. This study also suggests that the anolyte and catholyte replacement frequencies can be reduced, typically at a prolonged hydraulic retention time, thus minimizing the operating cost (e.g., solution pumping). The use of a high concentration of NaCl (35 g L-1) in the desalination chamber and catholyte provides a condition that is close to practicality.
    Matched MeSH terms: Protons
  18. Mediani A, Abas F, Maulidiani M, Abu Bakar Sajak A, Khatib A, Tan CP, et al.
    J Physiol Biochem, 2018 May 15.
    PMID: 29766441 DOI: 10.1007/s13105-018-0631-3
    Diabetes mellitus (DM) is a chronic disease that can affect metabolism of glucose and other metabolites. In this study, the normal- and obese-diabetic rats were compared to understand the diabetes disorders of type 1 and 2 diabetes mellitus. This was done by evaluating their urine metabolites using proton nuclear magnetic resonance (1H NMR)-based metabolomics and comparing with controls at different time points, considering the induction periods of obesity and diabetes. The biochemical parameters of the serum were also investigated. The obese-diabetic model was developed by feeding the rats a high-fat diet and inducing diabetic conditions with a low dose of streptozotocin (STZ) (25 mg/kg bw). However, the normal rats were induced by a high dose of STZ (55 mg/kg bw). A partial least squares discriminant analysis (PLS-DA) model showed the biomarkers of both DM types compared to control. The synthesis and degradation of ketone bodies, tricarboxylic (TCA) cycles, and amino acid pathways were the ones most involved in the variation with the highest impact. The diabetic groups also exhibited a noticeable increase in the plasma glucose level and lipid profile disorders compared to the control. There was also an increase in the plasma cholesterol and low-density lipoprotein (LDL) levels and a decline in the high-density lipoprotein (HDL) of diabetic rats. The normal-diabetic rats exhibited the highest effect of all parameters compared to the obese-diabetic rats in the advancement of the DM period. This finding can build a platform to understand the metabolic and biochemical complications of both types of DM and can generate ideas for finding targeted drugs.
    Matched MeSH terms: Protons
  19. Abdul-Hamid NA, Mediani A, Maulidiani M, Shadid K, Ismail IS, Abas F, et al.
    J Food Sci Technol, 2018 Apr;55(4):1541-1551.
    PMID: 29606769 DOI: 10.1007/s13197-018-3073-6
    The aim of this study was to examine the variation in metabolite constituents of five commercial varieties of date fruits; Ajwa, Safawi and Ambar which originated from Madinah, the Iranian Bam and Tunisian Deglet Noor. The differences of metabolome were investigated using proton nuclear magnetic resonance (1H NMR) spectroscopy combined with multivariate data analysis (MVDA). Principal Component Analysis (PCA) revealed clear separation between the date varieties. The Tunisian Deglet Noor demonstrated distinct cluster from the rest of the palm date samples based on the metabolite composition as shown by the pattern observed in Hierarchical Clustering Analysis (HCA) and PCA. Deglet Noor exhibited a significant higher level of sucrose (δ 5.40) and fructose (δ 4.16) in comparison with the other four varieties which can be associated with the distinctive sweet taste of this variety. Dates originated from Madinah and Tunisia exhibited a contrast manner in the amount of xylose and moisture content. These two aspects may contribute towards the soft texture of Tunisian dates. All Madinah dates were found to contain phenolic compounds which were well established as great antioxidant and anti-inflammatory agent. Ajwa dates exerted greater effect in inhibiting the generation of nitric oxide (NO) from the stimulated RAW264.7 cells at 95.37% inhibition. Succinic acid was suggested to have the most significant correlation with the trend of NO inhibitory shown by the selected date palm varieties.
    Matched MeSH terms: Protons
  20. Abdul Wahab MF, Mohamad Ghani NI, Kuppuswamy R
    Forensic Sci Int, 2012 Nov 30;223(1-3):53-63.
    PMID: 22955030 DOI: 10.1016/j.forsciint.2012.07.020
    Most of the automotive companies use cast iron for their engine blocks. Restoration of obliterated number on these iron surfaces by chemical etching is known to be quite difficult. Heating of the obliterated surface using oxyacetylene flame is an alternative recovery treatment suggested in literature and used in practice. However chemical etching has been established to be the most sensitive technique for detection of metal deformation present under stamped serial numbers. Hence, the current work investigated the suitability of some common etchants on cast iron surfaces with a view to determining the most suitable one for revealing the obliterated marks. The reagents tested were mostly copper containing Fry's reagent and its modifications. Two cast iron engine blocks (3.29%C and 3.1%C) of two cars--a Proton Saga and a Toyota--were utilized for the experiments. The engine blocks were cut into several small plates and each plate was stamped with some numerical characters at 8 kN load using Instron Table Mounted Universal Testing Machine. The depth of stamping impression varied between 0.2 mm and 0.3 mm. The stamped number was completely ground off manually using a metal file. The grounded surface was then polished smooth using emery papers and etched with a few selected reagents mostly by swabbing. Experimental results showed that a modified Fry's composition consisting of 4 5g CuCl(2), 100 mL HCl, and 180 mL H(2)O restored the number with better contrast at a reasonably shorter time. The above reagent is a slightly modified form of one of the Fry's original compositions--45 g CuCl(2), 180 mL HCl, and 100 mL H(2)O. Quite importantly the proposed reagent restored the original stamped numbers of both Proton and Toyota cars and also a Mitsubishi car that had been obliterated. The most widely used Fry's composition (90 g CuCl(2), 120 mL HCl and 100 mL H(2)O), although recovered the obliterated number, did not cause the desired contrast.
    Matched MeSH terms: Protons
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