Displaying publications 121 - 140 of 165 in total

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  1. Annuar, W.A., Abdullah, H.
    Ann Dent, 2003;10(1):-.
    MyJurnal
    This study is conducted to compare two resin luting cements (Rely XTMARC,3M and Compolute™ESPE) on their microleakage with one composite inlay system (Filtek™ Z250 Universal Restorative Materials, 3M). Thirty conventional inlays, Class II MOIDO cavity with gingival margin I mm above the cementoenamel junction, were prepared in premolar teeth. The composite inlays were fabricated directly on the prepared teeth using layering technique. Fifteen of the inlays were cemented with RelyTMX ARC and fifteen with Compolute™ (ESPE). The specimens were kept at 370 C for 10 days before thermocycling and immersed in methylene blue 2% solution for 24 hours. The teeth were sectioned mesio-distally. The site and degree of leakage of each section was scored using a visual scoring system under a stereomicroscope at a magnification of 1.5X. Results showed that there was no significant difference in'leakage extent (p>O.05), between Rely X™ARC and Compolute™. For both materials, leakage occurred most commonly within the enamel surface and between the cement-tooth interfaces. None of the leakage occurred between inlay - cement interface. There is no significant difference in the extent of leakage between Rely XTMARC compared to Compolute™.
    Matched MeSH terms: Methylene Blue
  2. Fatimah I, Prakoso NI, Sahroni I, Musawwa MM, Sim YL, Kooli F, et al.
    Heliyon, 2019 Nov;5(11):e02766.
    PMID: 31844705 DOI: 10.1016/j.heliyon.2019.e02766
    In this work, TiO2/SiO2 composite photocatalysts were prepared using biogenic silica extracted from bamboo leaves and titanium tetraisopropoxide as a titania precursor via a sol-gel mechanism. A study of the physicochemical properties of materials as a function of their titanium dioxide content was conducted using Fourier transform infrared spectroscopy, a scanning electron microscope, a diffuse reflectance ultraviolet-visible (UV-vis) spectrophotometer, and a gas sorption analyzer. The relationship between physicochemical parameters and photocatalytic performance was evaluated using the methylene blue (MB) photocatalytic degradation process under UV irradiation with and without the addition of H2O2 as an oxidant. The results demonstrated that increasing the TiO2 helps enhance the parameters of specific surface area, the pore volume, and the particle size of titanium dioxide, while the band gap energy reaches a maximum of 3.21 eV for 40% and 60% Ti content. The composites exhibit photocatalytic activity with the MB degradation with increasing photocatalytic efficiency since the composites with 40 and 60% wt. of TiO2 demonstrated the higher degradation rate compared with TiO2 in the presence and absence of H2O2. This higher rate is correlated with the higher specific surface area and band gap energy compared with those of TiO2.
    Matched MeSH terms: Methylene Blue
  3. Norazlina Hamzah, Faraizah Abd. Karim, Ahzad Hadi Ahmad, Narazah Mohd Yusoff
    MyJurnal
    Photochemical treatment is one of the pathogen inactivation method to treat plasma, part of a proactive approach used for blood and blood component safety. Three photochemical treatments that have been used were methylene blue, riboflavin and psoralen treatment. This study was done on Fresh Frozen Plasma (FFP) to evaluate the treatment effects of psoralen, methylene blue and riboflavin on coagulation factors level. Methods: FFP was collected from apheresis plasma units and kept at 22oC to 24oC. A sum of 90 apheresis plasma units and segments were used, separated from each bag and a part used as controls, placed in a -30oC freezer for storage, thawed, and coagulation proteins function was evaluated before and after treatment, at immediate, 30 days and 270 days storage. Results: Significant differences in fibrinogen and coagulation factor levels between before and after treatment with methylene blue, psoralen and riboflavin. However, most of the mean values in treated plasma were within reference ranges. Methylene blue treated FFP showed the lowest changes in fibrinogen and other coagulation factors level whilst riboflavin treated FFP demonstrated the highest changes in coagulation proteins concentrations especially for fibrinogen, FV, FVIII, FIX and FXII. However, FXIII showed the best recovery for all three photochemical methods with reduction level of 3% to 8% compared to pre-treatment. Storage time comparison of immediate, 30 days and 270 days was inconclusive. Conclusion: The coagulation proteins in psoralen treated FFP and MB-FFP were adequately preserved, where MB-FFP showed better preservation than other two photochemical treatments.
    Matched MeSH terms: Methylene Blue
  4. Ibrahim I, Lim HN, Huang NM
    Mikrochim Acta, 2019 06 14;186(7):452.
    PMID: 31201543 DOI: 10.1007/s00604-019-3547-x
    A multi-functional hybrid of cellulose acetate with cadmium sulfide and Methylene blue (CA/CdS/MB) in a bead composition was synthesized and investigated as a photosensor-adsorbent for the rapid, selective, and sensitive detection, and adsorption of Cu(II) ions. These hybrid CA-modified beads are composed of multiple adsorption active sites and possess a surface area of 58 cm2 g-1. They are an efficient adsorbent with a maximum adsorption capacity of 0.57 mg g-1. Photoelectrochemical (PEC) detection of Cu(II) was accomplished by modifying the beads on a glassy carbon electrode. The beads containing 20 mmol of sulfur displayed the widest linear analytical range (0.1-290 nM) and the lowest detection limit (16.9 nM) for Cu(II) with high selectivity and reliable reproducibility. The successful application of the beads has provided a new insight for the selection of a responsive photoactive material for a PEC assay, as well as an effective adsorbent material for Cu(II) ions. Graphical abstract A multi-functional hybrid of cellulose acetate with cadmium sulfide and Methylene blue (CA/CdS/MB) in a bead composition was synthesized and investigated as a photosensor-adsorbent for the rapid, selective and sensitive detection and adsorption of Cu(II) ions.
    Matched MeSH terms: Methylene Blue
  5. Jun LY, Karri RR, Mubarak NM, Yon LS, Bing CH, Khalid M, et al.
    Environ Pollut, 2020 Apr;259:113940.
    PMID: 31931415 DOI: 10.1016/j.envpol.2020.113940
    Jicama peroxidase (JP) was covalently immobilized onto functionalized multi-walled carbon nanotube (MWCNT) Buckypaper/Polyvinyl alcohol (BP/PVA) membrane and employed for degradation of methylene blue dye. The parameters of the isotherm and kinetic models are estimating using ant colony optimization (ACO), which do not meddle the non-linearity form of the respective models. The proposed inverse modelling through ACO optimization was implemented, and the parameters were evaluated to minimize the non-linear error functions. The adsorption of MB dye onto JP-immobilized BP/PVA membrane follows Freundlich isotherm model (R2 = 0.99) and the pseudo 1st order or 2nd kinetic model (R2 = 0.980 & 0.968 respectively). The model predictions from the parameters estimated by ACO resulted values close the experimental values, thus inferring that this approach captured the inherent characteristics of MB adsorption. Moreover, the thermodynamic studies indicated that the adsorption was favourable, spontaneous, and exothermic in nature. The comprehensive structural analyses have confirmed the successful binding of peroxidase onto BP/PVA membrane, as well as the effective MB dye removal using immobilized JP membrane. Compared to BP/PVA membrane, the reusability test revealed that JP-immobilized BP/PVA membrane has better dye removal performances as it can retain 64% of its dye removal efficiency even after eight consecutive cycles. Therefore, the experimental results along with modelling results demonstrated that JP-immobilized BP/PVA membrane is expected to bring notable impacts for the development of effective green and sustainable wastewater treatment technologies.
    Matched MeSH terms: Methylene Blue
  6. Wan Mat Khalir WKA, Shameli K, Jazayeri SD, Othman NA, Che Jusoh NW, Mohd Hassan N
    Nanomaterials (Basel), 2020 Jun 03;10(6).
    PMID: 32503127 DOI: 10.3390/nano10061104
    It is believed of great interest to incorporate silver nanoparticles (Ag-NPs) into stable supported materials using biological methods to control the adverse properties of nanoscale particles. In this study, in-situ biofabrication of Ag-NPs using Entada spiralis (E. spiralis) aqueous extract in Ceiba pentandra (C. pentandra) fiber as supporting material was used in which, the E. spiralis extract acted as both reducing and stabilizing agents to incorporate Ag-NPs in the C. pentandra fiber. The properties of Ag-NPs incorporated in the C. pentandra fiber (C. pentandra/Ag-NPs) were characterized using UV-visible spectroscopy (UV-vis), X-ray Diffraction (XRD), Field Emission Transmission Electron Microscope (FETEM), Scanning Electron Microscope (Scanning Electron Microscope (SEM), Energy Dispersive X-ray (EDX), Brunauer-Emmett-Teller (BET), Thermogravimetric (TGA) and Fourier Transform Infrared (FTIR) analyses. The average size of Ag-NPs measured using FETEM image was 4.74 nm spherical in shape. The C. pentandra/Ag-NPs was easily separated after application, and could control the release of Ag-NPs to the environment due to its strong attachment in C. pentandra fiber. The C. pentandra/Ag-NPs exposed good qualitative and quantitative antibacterial activities against Staphylococcus aureus (ATCC 25923), Enterococcus faecalis (ATCC 29212), Escherichia coli (ATCC 25922) and Proteus vulgaris (ATCC 33420). The dye catalytic properties of C. pentandra/Ag-NPs revealed the dye reduction time in which it was completed within 4 min for 20 mg/L rhodamine B and 20 min for 20 mg/L methylene blue dye, respectively. Based on the results, it is evident that C. pentandra/Ag-NPs are potentially promising to be applied in wound healing, textile, wastewater treatment, food packaging, labeling and biomedical fields.
    Matched MeSH terms: Methylene Blue
  7. Akhtar K, Ali F, Sohni S, Kamal T, Asiri AM, Bakhsh EM, et al.
    Environ Sci Pollut Res Int, 2020 Jan;27(1):823-836.
    PMID: 31811610 DOI: 10.1007/s11356-019-06908-y
    Lignocellulosic biomass waste is a cheap, eco-friendly, and sustainable raw material for a wide array of applications. In the present study, an easy, fast, and economically feasible route has been proposed for the preparation of different zero-valent metal nanoparticles (ZV-MNPs) based on Cu, Co, Ag, and Ni NPs using empty fruit bunch (EFB) biomass residue as support material. The catalytic efficiency of ZV-MNPs/EFB catalyst was investigated against five model pollutants, such as methyl orange (MO), congo red (CR), methylene blue (MB), acridine orange (AO), and 4-nitrophenol (4-NP) using NaBH4 as a source of hydrogen and electron. Comparative study revealed that among as-prepared ZV-MNPs/EFB catalysts, Cu-NPs immobilized onto EFB (Cu/EFB) exhibited maximum catalytic efficiency towards pollutant abasement. Degradation reactions were highly efficient, and were completed within a short time (4 min) in case of MO, CR, and MB, whilst AO and 4-NP were reduced in less than 15 min. Kinetic investigation revealed that the degradation rate of model pollutants accorded with pseudo-first order model. Furthermore, supported catalysts were easily recovered after the completion of experiment by simply pulling the catalyst from reaction system. Recyclability tests performed on Cu/EFB revealed that more than 97% of the reduction was achieved in case of MO dye for four successive cycles of reuse. The as-prepared heterostructure showed multifunctional properties, such as enhanced uptake of contaminants, high catalytic efficiency, and easy recovery, hence, offers great prospects in wastewater purification.
    Matched MeSH terms: Methylene Blue
  8. Jawad AH, Abdulhameed AS, Khadiran T, ALOthman ZA, Wilson LD, Algburi S
    Int J Phytoremediation, 2024;26(5):727-739.
    PMID: 37817463 DOI: 10.1080/15226514.2023.2262040
    In this study, the focus was on utilizing tropical plant biomass waste, specifically bamboo (BB), as a sustainable precursor for the production of activated carbon (BBAC) via pyrolysis-induced K2CO3 activation. The potential application of BBAC as an effective adsorbent for the removal of methylene blue (MB) dye from aqueous solutions was investigated. Response surface methodology (RSM) was employed to evaluate key adsorption characteristics, which included BBAC dosage (A: 0.02-0.08 g/L), pH (B: 4-10), and time (C: 2-8 min). The adsorption isotherm analysis revealed that the adsorption of MB followed the Freundlich model. Moreover, the kinetic data were well-described by the pseudo-second-order model, suggesting the role of a chemisorption process. The BBAC demonstrated a notable MB adsorption capacity of 195.8 mg/g, highlighting its effectiveness as an adsorbent. Multiple mechanisms were identified as controlling factors in MB adsorption by BBAC, including electrostatic forces, π-π stacking, and H-bonding interactions. The findings of this study indicate that BBAC derived from bamboo has the potential to be a promising adsorbent for the treatment of wastewater containing organic dyes. The employment of sustainable precursors like bamboo for activated carbon production contributes to environmentally friendly waste management practices and offers a solution for the remediation of dye-contaminated wastewater.
    Matched MeSH terms: Methylene Blue
  9. Reghioua A, Atia D, Hamidi A, Jawad AH, Abdulhameed AS, Mbuvi HM
    Int J Biol Macromol, 2024 Apr;263(Pt 1):130304.
    PMID: 38382796 DOI: 10.1016/j.ijbiomac.2024.130304
    This present work targets the production of an eco-friendly adsorbent (hereinafter KA/CEL) from kaolin clay functionalized with cellulose extract obtained from peanut shells. The adsorbents were used for decolorization of two different types of organic dyes (cationic: methylene blue, MB; anionic: Congo red, CR) from an aqueous environment. Several analytical methods, including Brunauer-Emmett-Teller (surface properties), Fourier Transforms infrared (functionality), scanning electron microscope, Energy dispersive X-Ray (morphology), and pHpzc test (surface charge), were used to attain the physicochemical characteristics of KA/CEL. The Box-Behnken Design (BBD) was applied to determine the crucial factors affecting adsorption performance. These included cellulose loading at 25 %, an adsorbent dose of 0.06 g, solution pH set at 10 for MB and 7 for CR, a temperature of 45 °C, and contact times of 12.5 min for MB and 20 min for CR dye. The adsorption data exhibited better agreement with the pseudo-second-order kinetic and Freundlich models. The Langmuir model estimated the monolayer capacity to be 291.5 mg/g for MB and 130.7 mg/g for CR at a temperature of 45 °C. This study's pivotal finding underscores the promising potential of KA/CEL as an effective adsorbent for treating wastewater contaminated with organic dyes.
    Matched MeSH terms: Methylene Blue
  10. Sani MH, Zakaria ZA, Balan T, Teh LK, Salleh MZ
    PMID: 22611437 DOI: 10.1155/2012/890361
    Muntingia calabura L. (family Elaeocarpaceae) has been traditionally used to relieve various pain-related ailments. The present study aimed to determine the antinociceptive activity of methanol extract of M. calabura leaves (MEMC) and to elucidate the possible mechanism of antinociception involved. The in vivo chemicals (acetic acid-induced abdominal constriction and formalin-, capsaicin-, glutamate-, serotonin-induced paw licking test) and thermal (hot plate test) models of nociception were used to evaluate the extract antinociceptive activity. The extract (100, 250, and 500 mg/kg) was administered orally 60 min prior to subjection to the respective test. The results obtained demonstrated that MEMC produced significant (P < 0.05) antinociceptive response in all the chemical- and thermal-induced nociception models, which was reversed after pretreatment with 5 mg/kg naloxone, a non-selective opioid antagonist. Furthermore, pretreatment with L-arginine (a nitric oxide (NO) donor), N(G)-nitro-L-arginine methyl esters (L-NAME; an inhibitor of NO synthase (NOS)), methylene blue (MB; an inhibitor of cyclic-guanosine monophosphate (cGMP) pathway), or their combination also caused significant (P < 0.05) change in the intensity of the MEMC antinociception. In conclusion, the MEMC antinociceptive activity involves activation of the peripheral and central mechanisms, and modulation via, partly, the opioid receptors and NO/cGMP pathway.
    Matched MeSH terms: Methylene Blue
  11. Wahid NB, Latif MT, Suratman S
    Chemosphere, 2013 Jun;91(11):1508-16.
    PMID: 23336924 DOI: 10.1016/j.chemosphere.2012.12.029
    This study was conducted to determine the composition and source apportionment of surfactant in atmospheric aerosols around urban and semi-urban areas in Malaysia based on ionic compositions. Colorimetric analysis was undertaken to determine the concentrations of anionic surfactants as Methylene Blue Active Substances (MBAS) and cationic surfactants as Disulphine Blue Active Substances (DBAS) using a UV spectrophotometer. Ionic compositions were determined using ion chromatography for cations (Na(+), NH4(+), K(+), Mg(2+), Ca(2+)) and anions (F(-), Cl(-), NO3(-), SO4(2-)). Principle component analysis (PCA) combined with multiple linear regression (MLR) were used to identify the source apportionment of MBAS and DBAS. Results indicated that the concentrations of surfactants at both sampling sites were dominated by MBAS rather than DBAS especially in fine mode aerosols during the southwest monsoon. Three main sources of surfactants were identified from PCA-MLR analysis for MBAS in fine mode samples particularly in Kuala Lumpur, dominated by motor vehicles, followed by soil/road dust and sea spray. Besides, for MBAS in coarse mode, biomass burning/sea spray were the dominant source followed by motor vehicles/road dust and building material.
    Matched MeSH terms: Methylene Blue/chemistry
  12. Ikram M, Mahmood A, Haider A, Naz S, Ul-Hamid A, Nabgan W, et al.
    Int J Biol Macromol, 2021 Aug 31;185:153-164.
    PMID: 34157328 DOI: 10.1016/j.ijbiomac.2021.06.101
    Various concentrations of Mg into fixed amount of cellulose nanocrystals (CNC)-doped ZnO were synthesized using facile chemical precipitation. The aim of present study is to remove dye degradation of methylene blue (MB) and bactericidal behavior with synthesized product. Phase constitution, functional group analysis, optical behavior, elemental composition, morphology and microstructure were examined using XRD, FTIR, UV-Vis spectrophotometer, EDS and HR-TEM. Highly efficient photocatalytic performance was observed in basic medium (98%) relative to neutral (65%), and acidic (83%) was observed upon Mg and CNC co-doping. Significant bactericidal activity of doped ZnO nanoparticles depicted inhibition zones for G -ve and +ve bacteria ranging (2.20 - 4.25 mm) and (5.80-7.25 mm) for E. coli and (1.05 - 2.75 mm) and (2.80 - 4.75 mm) for S. aureus at low and high doses, respectively. Overall, doped nanostructures showed significant (P 
    Matched MeSH terms: Methylene Blue/chemistry*
  13. Md Sani ND, Ariffin EY, Sheryn W, Shamsuddin MA, Heng LY, Latip J, et al.
    Sensors (Basel), 2019 Nov 22;19(23).
    PMID: 31766637 DOI: 10.3390/s19235111
    A toxicity electrochemical DNA biosensor has been constructed for the detection of carcinogens using 24 base guanine DNA rich single stranded DNA, and methylene blue (MB) as the electroactive indicator. This amine terminated ssDNA was immobilized onto silica nanospheres and deposited on gold nanoparticle modified carbon-paste screen printed electrodes (SPEs). The modified SPE was initially exposed to a carcinogen, followed by immersion in methylene blue for an optimized duration. The biosensor response was measured using differential pulse voltammetry. The performance of the biosensor was identified on several anti-cancer compounds. The toxicity DNA biosensor demonstrated a linear response range to the cadmium chloride from 0.0005 ppm to 0.01 ppm (R2 = 0.928) with a limit of detection at 0.0004 ppm. The biosensor also exhibited its versatility to screen the carcinogenicity of potential anti-cancer compounds.
    Matched MeSH terms: Methylene Blue/chemistry*
  14. Nasrullah A, Bhat AH, Naeem A, Isa MH, Danish M
    Int J Biol Macromol, 2018 Feb;107(Pt B):1792-1799.
    PMID: 29032214 DOI: 10.1016/j.ijbiomac.2017.10.045
    High surface area mesoporous activated carbon-alginate (AC-alginate) beads were successfully synthesized by entrapping activated carbon powder derived from Mangosteen fruit peel into calcium-alginate beads for methylene blue (MB) removal from aqueous solution. The structure and surface characteristics of AC-alginate beads were analyzed using Fourier transform infra-red (FTIR) spectroscopy, scanning electron microscopy (SEM) and surface area analysis (SBET), while thermal properties were tested using thermogravimetric analysis (TGA). The effect of AC-alginate dose, pH of solution, contact time, initial concentration of MB solution and temperature on MB removal was elucidated. The results showed that the maximum adsorption capacity of 230mg/g was achieved for 100mg/L of MB solution at pH 9.5 and temperature 25°C. Furthermore, the adsorption of MB on AC-alginate beads followed well pseudo-second order equation and equilibrium adsorption data were better fitted by the Freundlich isotherm model. The findings reveal the feasibility of AC-alginate beads composite to be used as a potential and low cost adsorbent for removal of cationic dyes.
    Matched MeSH terms: Methylene Blue/chemistry*
  15. Rashid JI, Yusof NA, Abdullah J, Hashim U, Hajian R
    PMID: 25491829 DOI: 10.1016/j.msec.2014.09.010
    This work describes the incorporation of SiNWs/AuNPs composite as a sensing material for DNA detection on indium tin-oxide (ITO) coated glass slide. The morphology of SiNWs/AuNPs composite as the modifier layer on ITO was studied by scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX). The morphological studies clearly showed that SiNWs were successfully decorated with 20 nm-AuNPs using self-assembly monolayer (SAM) technique. The effective surface area for SiNWs/AuNPs-modified ITO enhanced about 10 times compared with bare ITO electrode. SiNWs/AuNPs nanocomposite was further explored as a matrix for DNA probe immobilization in detection of dengue virus as a bio-sensing model to evaluate its performance in electrochemical sensors. The hybridization of complementary DNA was monitored by differential pulse voltammetry (DPV) using methylene blue (MB) as the redox indicator. The fabricated biosensor was able to discriminate significantly complementary, non-complementary and single-base mismatch oligonucleotides. The electrochemical biosensor was sensitive to target DNA related to dengue virus in the range of 9.0-178.0 ng/ml with detection limit of 3.5 ng/ml. In addition, SiNWs/AuNPs-modified ITO, regenerated up to 8 times and its stability was up to 10 weeks at 4°C in silica gel.
    Matched MeSH terms: Methylene Blue/chemistry
  16. Foo KY, Hameed BH
    Bioresour Technol, 2012 May;112:143-50.
    PMID: 22414577 DOI: 10.1016/j.biortech.2012.01.178
    The feasibility of preparing activated carbon (JPAC) from jackfruit peel, an industrial residue abundantly available from food manufacturing plants via microwave-assisted NaOH activation was explored. The influences of chemical impregnation ratio, microwave power and radiation time on the properties of activated carbon were investigated. JPAC was examined by pore structural analysis, scanning electron microscopy, Fourier transform infrared spectroscopy, nitrogen adsorption isotherm, elemental analysis, surface acidity/basicity and zeta potential measurements. The adsorptive behavior of JPAC was quantified using methylene blue as model dye compound. The best conditions resulted in JPAC with a monolayer adsorption capacity of 400.06 mg/g and carbon yield of 80.82%. The adsorption data was best fitted to the pseudo-second-order equation, while the adsorption mechanism was well described by the intraparticle diffusion model. The findings revealed the versatility of jackfruit peels as good precursor for preparation of high quality activated carbon.
    Matched MeSH terms: Methylene Blue/chemistry
  17. Foo KY, Hameed BH
    Bioresour Technol, 2012 Jul;116:522-5.
    PMID: 22595094 DOI: 10.1016/j.biortech.2012.03.123
    The feasibility of langsat empty fruit bunch waste for preparation of activated carbon (EFBLAC) by microwave-induced activation was explored. Activation with NaOH at the IR ratio of 1.25, microwave power of 600 W for 6 min produced EFBLAC with a carbon yield of 81.31% and adsorption uptake for MB of 302.48 mg/g. Pore structural analysis, scanning electron microscopy and Fourier transform infrared spectroscopy demonstrated the physical and chemical characteristics of EFBLAC. Equilibrium data were best described by the Langmuir isotherm, with a monolayer adsorption capacity of 402.06 mg/g, and the adsorption kinetics was well fitted to the pseudo-second-order equation. The findings revealed the potential to prepare high quality activated carbon from langsat empty fruit bunch waste by microwave irradiation.
    Matched MeSH terms: Methylene Blue/isolation & purification
  18. Yeo JL, Tan BT, Achike FI
    Eur J Pharmacol, 2010 Sep 10;642(1-3):99-106.
    PMID: 20553918 DOI: 10.1016/j.ejphar.2010.05.040
    Acidosis modulates physiologic and pathophysiologic processes but the mechanism of acidotic vasodilatation remains unclear. We therefore explored this in aortic rings from normal and streptozotocin-induced diabetic Sprague-Dawley rats. Phenylephrine (PE)-induced contraction in endothelium-intact and -denuded rings were recorded under normal and acidotic pH with or without drug probes. Acidosis exerted a relaxant effect in endothelium-intact and -denuded euglycaemic and diabetic tissues. l-NAME or methylene blue partially inhibited acidotic relaxation in these endothelium-intact but not the -denuded tissues, with greater inhibition in the diabetic tissues, indicating that acidosis induces relaxation by endothelium-dependent and -independent mechanisms, the former being EDNO-cGMP mediated. Indomethacin had no effect on the tissues, indicating that cyclooxygenase products are neither involved in acidosis-induced vasodilatation nor in the modulation of phenylephrine-contraction. In euglycaemic tissues under normal pH, no K(+) channel blocker altered phenylephrine-contraction, but all (except glibenclamide) enhanced diabetic tissue contraction, indicating that normally, these channels (K(ir), K(V), BK(Ca), K(ATP)) do not modulate phenylephrine-contraction, but they (except K(ATP)) are expressed in diabetes where they attenuate phenylephine-induced contraction and modulate acidosis. Only the K(ir) channel modulates acidotic relaxation in euglycaemic tissues. Only tetraethylammonium and iberiotoxin enhanced phenylephrine-induced contraction in endothelium-denuded diabetic tissues indicating that BK(Ca) attenuates phenylephrine-contraction and that acidotic relaxation in this condition is modulated by a tetraethylammonium-sensitive mechanism. In conclusion, acidosis causes vasodilatation in normal and diabetic tissues via endothelium-dependent and -independent mechanisms differentially modulated by a combination of a NO-cGMP process and K(+) channels, some of which are dormant in the normal state but activated in diabetes mellitus.
    Matched MeSH terms: Methylene Blue/pharmacology
  19. Abdullah AZ, Ling PY
    J Hazard Mater, 2010 Jan 15;173(1-3):159-67.
    PMID: 19740600 DOI: 10.1016/j.jhazmat.2009.08.060
    The ambient sonocatalytic degradation of congo red, methyl orange, and methylene blue by titanium dioxide (TiO(2)) catalyst at initial concentrations between 10 and 50mg/L, catalyst loadings between 1.0 and 3.0mg/L and hydrogen peroxide (H(2)O(2)) concentrations up to 600 mg/L is reported. A 20 kHz ultrasonic processor at 50 W was used to accelerate the reaction. The catalysts were exposed to heat treatments between 400 and 1000 degrees C for up to 4h to induce phase change. Sonocatalysts with small amount of rutile phase showed better sonocatalytic activity but excessive rutile phase should be avoided. TiO(2) heated to 800 degrees C for 2h showed the highest sonocatalytic activity and the degradation of dyes was influenced by their chemical structures, chemical phases and characteristics of the catalysts. Congo red exhibited the highest degradation rate, attributed to multiple labile azo bonds to cause highest reactivity with the free radicals generated. An initial concentration of 10mg/L, 1.5 g/L of catalyst loading and 450 ppm of H(2)O(2) gave the best congo red removal efficiency of above 80% in 180 min. Rate coefficients for the sonocatalytic process was successfully established and the reused catalyst showed an activity drop by merely 10%.
    Matched MeSH terms: Methylene Blue/chemistry
  20. Zakaria ZA, Sulaiman MR, Somchit MN, Jais AM, Ali DI
    J Pharm Pharm Sci, 2005;8(2):199-206.
    PMID: 16124931
    To determine the involvement of nitric oxide/cyclic guanosine monophosphate (NO/cGMP) pathway in aqueous supernatant of haruan (Channa striatus) fillet (ASH) antinociception using the acetic acid-induced abdominal constriction test.
    Matched MeSH terms: Methylene Blue/pharmacology*
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