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Methanol (Non-Cancer)

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The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Application of High-speed Countercurrent Chromatography-Evaporative Light Scattering Detection for the Separation of Seven Steroidal Saponins from Dioscorea villosa

Authors: Yoon, KD; Chin, YW; Yang, MH; Choi, J; Kim, J (In Press) Phytochemical Analysis. HERO ID: 1037843

[Less] INTRODUCTION: Steroidal saponins in Dioscorea species are chemically characterised as spirostanol and . . . [More] INTRODUCTION: Steroidal saponins in Dioscorea species are chemically characterised as spirostanol and furostanol saponins, and have been used as standard marker compounds due to their chemotaxonomical significance and their important biological activities. OBJECTIVE: To design a simple, rapid and efficient method for the separation of steroidal saponins with a high degree of purity using high-speed countercurrent chromatography (HSCCC) coupled with evaporative light scattering detection (ELSD). METHODOLOGY: In the first step, reversed-phase mode HSCCC (flow rate: 1.5 mL/min; revolution speed: 800 rpm) using n-hexane:n-butanol:water [3:7:10 (v/v/v)] was employed to separate furostanol saponins from n-butanol soluble extracts of Dioscorea villosa. After the first HSCCC run, spirostanol saponins retained in the stationary phase were subjected to the second HSCCC (normal-phase mode; flow rate: 2.0 mL/min; revolution speed: 800 rpm). A two-phase solvent system composed of chloroform:methanol:isopropanol:water [10:6:1:4 (v/v/v/v)] was employed in the second HSCCC. The structures of isolates were elucidated by (1) H-NMR, (13)  C-NMR, ESI-MS and HPLC analysis. RESULTS: Three furostanol saponins, parvifloside (27.3 mg), methyl protodeltonin (67.1 mg) and trigofoenoside A-1 (18.5 mg) were isolated from the n-butanol soluble extract of D. villosa by the first HSCCC run. Subsquent normal-phase HSCCC of the spirostanol-rich extract led to the separation of four spirostanol saponins: zingiberensis saponin I (15.2 mg), deltonin (31.5 mg), dioscin (7.7 mg) and prosapogenin A of dioscin (3.4 mg). Copyright © 2012 John Wiley & Sons, Ltd.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Simultaneous determination of tyrosine, tryptophan and 5-hydroxytryptamine in serum of MDD patients by high performance liquid chromatography with fluorescence detection

Authors: Sa, M; Ying, L; Tang, AG; Xiao, LD; Ren, YP (In Press) . HERO ID: 1037853

[Less] BACKGROUND: Tyrosine (Tyr), Tryptophan (Trp) and 5-hydroxytryptamine (5-HT) are important amino acids . . . [More] BACKGROUND: Tyrosine (Tyr), Tryptophan (Trp) and 5-hydroxytryptamine (5-HT) are important amino acids in vivo and have been hypothesized to be involved in many mental disorders. We developed a rapid and sensitive HPLC method for simultaneous measurement of serum Tyr, Trp and 5-HT and explored the clinical significances of Tyr, Trp and 5-HT and the 5-HT/Trp ratio for patients with major depressive disorder (MDD) disease. METHODS: Serum samples were deproteinized by 5% perchloric acid and separated on an Atlantis C18 column (4.6×150mm, 5μm) with the mobile phase consisting of 0.1mol/l KH(2)PO(4) and methanol (85:15, V/V).The eluates were monitored by the fluorescence detection with programmed wavelength. RESULTS: Analysis was achieved in <12.0min. The limits of quantification were 0.014, 0.005, and 0.024μmol/l for Tyr, Trp and 5-HT, respectively. Reproducibility and recovery were satisfactory. Tyr, Trp and 5-HT and the 5-HT/Trp ratio were significantly decreased in patients with MDD. CONCLUSIONS: In diseases, like MDD, Tyr, Trp and 5-HT play an important role. This method can potentially be applied as prognostic or diagnostic tool or even to follow the evolution of the illness or of the treatment.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Synthesis and Evaluation of (2-(4-Methoxyphenyl)-4-quinolinyl)(2-piperidinyl)methanol (NSC23925) Isomers To Reverse Multidrug Resistance in Cancer

Authors: Duan, Z; Li, X; Huang, H; Yuan, W; Zheng, SL; Liu, X; Zhang, Z; Choy, E; Harmon, D; Mankin, H; Hornicek, F (In Press) Journal of Medicinal Chemistry. HERO ID: 1037859

[Less] Development of multidrug resistance (MDR) during chemotherapy is a fundamental obstacle associated with . . . [More] Development of multidrug resistance (MDR) during chemotherapy is a fundamental obstacle associated with cancer care. Prior studies have identified (2-(4-methoxyphenyl)-4-quinolinyl)(2-piperidinyl)methanol (5) (NSC23925) to be a small molecule agent that reverses MDR in cancer cells. We synthesized all four isomers of 5 and analyzed them by liquid chromatography-mass spectrometry (LCMS). Structure-activity relationships for reversing MDR were evaluated. Isomer 11 demonstrated the most potent activity. 11 reversed MDR in several drug-resistant cell lines expressing Pgp, including ovarian, breast, colon, uterine, and sarcoma cancer. 11 resensitized these cell lines to paclitaxel, doxorubicin, mitoxantrone, vincristine, and trabectedin with no effect on cell sensitivity to cisplatin, topotecan, and methotrexate. 11 significantly enhanced in vivo antitumor activity of paclitaxel in MDR xenograft models, without increasing the level of paclitaxel toxicity. In conclusion, 11 and derivatives of this compound may hold therapeutic value in the treatment of MDR-dependent cancers.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Antimicrobial activity of sesquiterpene lactones isolated from traditional medicinal plant, Costus speciosus (Koen ex.Retz.) Sm

Authors: Duraipandiyan, V; Al-Harbi, NA; Ignacimuthu, S; Muthukumar, C (In Press) BMC Complementary and Alternative Medicine. HERO ID: 1037869

[Less] ABSTRACT: BACKGROUND: Costus speciosus (Koen ex.Retz.) Sm (Costaceae) is an Indian ornamental plant . . . [More] ABSTRACT: BACKGROUND: Costus speciosus (Koen ex.Retz.) Sm (Costaceae) is an Indian ornamental plant which has long been used medicinally in traditional systems of medicine. The plant has been found to possess diverse pharmacological activities. Rhizomes are used to treat pneumonia, rheumatism, dropsy, urinary diseases, jaundice, skin diseases and leaves are used to treat mental disorders. METHOD: Antibacterial and antifungal activities were tested using Disc diffusion method and Minimum Inhibitory Concentration (MIC). Column chromatography was used to isolate compounds from hexane extract. X-ray crystallography technique and GC-MS analysis were used to identify the compounds RESULTS: Antibacterial and antifungal activities were observed in hexane, chloroform, ethyl acetate and methanol extracts. Hexane extract of C.speciosus showed good activity against tested fungi also. Two sesquiterpenoid compounds were isolated (costunolide and eremanthin) from the hexane extract. Both the compounds did not inhibit the growth of tested bacteria. But, both the compounds inhibited the tested fungi. The compound costunolide showed significant antifungal activity. The MIC values of costunolide were; 62.5 mug/ml against Trichophyton mentagrophytes, 62. mug/ml against T. simii, 31.25 mug/ml against T. rubrum 296, 62.5 mug/ml against T. rubrum 57, 125 mug/ml against Epidermophyton floccosum, 250 mug/ml against Scopulariopsis sp, 250 mug/ml against Aspergillus niger, 125 mug/ml against Curvulari lunata, 250 mug/ml against Magnaporthe grisea. CONCLUSION: Hexane extract showed promising antibacterial and antifungal activity. The isolated compound costunolide showed good antifungal activity.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Effects of Hypericum montbretti Extract on the Central Nervous System and Involvement of GABA (A)/Benzodiazepine Receptors in its Pharmacological Activity

Authors: Can, OD; Ozkay, UD (In Press) . HERO ID: 1037875

[Less] The present study was undertaken to investigate the putative activity of a methanol extract of Hypericum . . . [More] The present study was undertaken to investigate the putative activity of a methanol extract of Hypericum montbretti (Guttiferae) on the central nervous system. Rutin (1519 ppm) and quercitrin (784 ppm) were identified as the major phenolic compounds in the extract. When administered at 25, 50 and 100 mg/kg doses, the extract decreased the total number of head-dipping behaviours performed by mice during a hole-board test. Administration of both the extract and diazepam (2 mg/kg) reduced spontaneous locomotory activity, potentiated hexobarbital (60 mg/kg)-induced sleeping parameters and prevented pentylenetetrazole (80 mg/kg)-induced seizures relative to the controls. These findings are the first to indicate the sedative and anticonvulsant activities of H. montbretti extract. Atropine (2 mg/kg) and naloxone (5 mg/kg) pre-treatment did not reverse the sedative effect, indicating that muscarinic and opioidergic mechanisms did not contribute to the pharmacological action. However, pre-treatment with flumazenil (a benzodiazepine receptor antagonist) reversed both the sedative and anticonvulsant effects induced by a 100 mg/kg dose of the extract, indicating the involvement of the GABA(A)-benzodiazepine receptor complex. In conclusion, H. montbretti extract is a novel candidate as a sedative and anticonvulsant drug for the treatment of sleep disorders and for the prevention of epileptic seizures. Copyright © 2012 John Wiley & Sons, Ltd.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

The dual pathway in action: decoupling parallel routes for CO(2) production during the oscillatory electro-oxidation of methanol

Authors: Nagao, R; Cantane, DA; Lima, FH; Varela, H (In Press) Physical Chemistry Chemical Physics. HERO ID: 1037877

[Less] As in the case of most small organic molecules, the electro-oxidation of methanol to CO(2) is believed . . . [More] As in the case of most small organic molecules, the electro-oxidation of methanol to CO(2) is believed to proceed through a so-called dual pathway mechanism. The direct pathway proceeds via reactive intermediates such as formaldehyde or formic acid, whereas the indirect pathway occurs in parallel, and proceeds via the formation of adsorbed carbon monoxide (CO(ad)). Despite the extensive literature on the electro-oxidation of methanol, no study to date distinguished the production of CO(2) from direct and indirect pathways. Working under, far-from-equilibrium, oscillatory conditions, we were able to decouple, for the first time, the direct and indirect pathways that lead to CO(2) during the oscillatory electro-oxidation of methanol on platinum. The CO(2) production was followed by differential electrochemical mass spectrometry and the individual contributions of parallel pathways were identified by a combination of experiments and numerical simulations. We believe that our report opens some perspectives, particularly as a methodology to be used to identify the role played by surface modifiers in the relative weight of both pathways-a key issue to the effective development of catalysts for low temperature fuel cells.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Extinction coefficient for red-shifted chlorophylls: Chlorophyll d and chlorophyll f

Authors: Li, Y; Scales, N; Blankenship, RE; Willows, RD; Chen, M (In Press) Biochimica et Biophysica Acta. HERO ID: 1037880

[Less] Both chlorophyll f and chlorophyll d are red-shifted chlorophylls in oxygenic photosynthetic organisms, . . . [More] Both chlorophyll f and chlorophyll d are red-shifted chlorophylls in oxygenic photosynthetic organisms, which extend photon absorbance into the near infrared region. This expands the range of light that can be used to drive photosynthesis. Quantitative determination of chlorophylls is a crucial step in the investigation of chlorophyll-photosynthetic reactions in the field of photobiology and photochemistry. No methods have yet been worked out for the quantitative determination of chlorophyll f. There is also no method available for the precise quantitative determination of chlorophyll d although it was discovered in 1943. In order to obtain the extinction coefficients (ε) of chlorophyll f and chlorophyll d, the concentrations of chlorophylls were determined by Inductive Coupled Plasma Mass Spectrometry according to the fact that each chlorophyll molecule contains one magnesium (Mg) atom. Molar extinction coefficient ε(chl f) is 71.11×10(3)Lmol(-1)A(707nm)cm(-1) and ε(chl d) is 63.68×10(3)Lmol(-1)A(697nm)cm(-1) in 100% methanol. This article is part of a Special Issue entitled: Photosynthesis Research for Sustainability: From Natural to Artificial Photosynthesis.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

On the Role of Hydrogen Bonds in Photoinduced Electron-Transfer Dynamics between 9-Fluorenone and Amine Solvents

Authors: Ghosh, HN; Adamczyk, K; Verma, S; Dreyer, J; Nibbering, ET (In Press) Chemistry: A European Journal. HERO ID: 1037905

[Less] Using ultrafast fluorescence upconversion and mid-infrared spectroscopy, we explore the role of hydrogen . . . [More] Using ultrafast fluorescence upconversion and mid-infrared spectroscopy, we explore the role of hydrogen bonds in the photoinduced electron transfer (ET) between 9-fluorenone (FLU) and the solvents trimethylamine (TEA) and dimethylamine (DEA). FLU shows hydrogen-bond dynamics in the methanol solvent upon photoexcitation, and similar effects may be anticipated when using DEA, whereas no hydrogen bonds can occur in TEA. Photoexcitation of the electron-acceptor dye molecule FLU with a 400 nm pump pulse induces ultrafast ET from the amine solvents, which is followed by 100 fs IR probe pulses as well as fluorescence upconversion, monitoring the time evolution of marker bands of the FLU S(1) state and the FLU radical anion, and an overtone band of the amine solvent, marking the transient generation of the amine radical cation. A comparison of the experimentally determined forward charge-separation and backward charge-recombination rates for the FLU-TEA and FLU-DEA reaction systems with the driving-force dependencies calculated for the forward and backward ET rates reveals that additional degrees of freedom determine the ET reaction dynamics for the FLU-DEA system. We suggest that hydrogen bonding between the DEA molecules plays a key role in this behaviour.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Microdialysis combined with liquid chromatography-tandem mass spectrometry for the determination of levo-tetrahydropalmatine in the rat striatum

Authors: Wang, C; Li, S; Tang, Y; Wang, S; Zhang, Y; Fan, G; Li, L; Zhang, Y (In Press) Journal of Pharmaceutical and Biomedical Analysis. HERO ID: 1037907

[Less] Levo-tetrahydropalmatine (l-THP), one of the main active alkaloids isolated from Rhizoma corydalis, . . . [More] Levo-tetrahydropalmatine (l-THP), one of the main active alkaloids isolated from Rhizoma corydalis, was recently found to elicit profound effects on the dopaminergic system in the striatum, which plays an important role in regulating nociception. A rapid and sensitive method based on microdialysis combined with liquid chromatography-tandem mass spectrometry was developed for the determination of l-THP in the rat striatum. Microdialysis probes were stereotactically placed in the striatal hemisphere, and l-THP was measured from the microdialysates collected using LC-MS/MS. Reverse-phase LC separation was accomplished on a Diamonsil™ C18 column (50mm×2.1mm ID, 5μm) with the mobile phase composed of methanol-water (50:50, v/v) at a flow rate of 0.2ml/min. The method had a chromatographic total run time of 5min. Detection was performed in electrospray positive mode and quantification was executed in selected reaction monitoring mode. The following transitions were monitored: m/z 356.0→191.9 for l-THP and 256.0→167.1 for the internal standard diphenhydramine. The method was sensitive with a lower limit of quantitation (LLOQ) of 0.1ng/ml for l-THP, with good linearity in the range of 0.1-1000ng/ml (r(2)≥0.999). All the validation data, such as accuracy, precision, and inter-day repeatability were within the required limits. The method was successfully applied to pharmacokinetic study of the l-THP in the rat striatum.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

The effects of dynamic changes of malonyl ginsenosides on evaluation and quality control of Panax ginseng C.A. Meyer

Authors: Liu, Z; Li, Y; Li, X; Ruan, CC; Wang, LJ; Sun, GZ (In Press) Journal of Pharmaceutical and Biomedical Analysis. HERO ID: 1037908

[Less] To clarify the effects of malonyl ginsenosides (MGR) on evaluation and quality control of Panax ginseng, . . . [More] To clarify the effects of malonyl ginsenosides (MGR) on evaluation and quality control of Panax ginseng, the contents of neutral and malonyl ginsenosides from P. ginseng were examined by high-performance liquid chromatography equipped with UV-VIS detector (HPLC-UV) during extraction, processing and storage. Several solvents, including water, ethanol, methanol, and n-butanol were used in the cold-soaked extraction (CSE). Among the four extraction solvents, methanol was found to be the most efficient. CSE was compared with other extraction methods such as Soxhlet extraction (SE), heat reflux extraction (HRE), ultrasonic-assisted extraction (UAE), and microwave-assisted extraction (MAE). The content of MGR showed significant differences, higher in CSE and UAE; lower in MAE and HRE; no MGR could be detected after SE. However, the total contents of neutral and malonyl ginsenosides were not different. Meanwhile, white ginseng, stored at 25°C in air of low humidity, showed a marked decrease in the concentration of MGR from 1.19% to 0.63% but with an increase in the neutral ginsenosides from 1.12% to 1.53% after 0-9-month storage. The results indicated that MGR changed dynamically in P. ginseng with different extraction solvents, extraction methods and increasing storage time. The total ginsenosides was not only underestimated but also determined imprecisely by ignoring malonyl ginsenosides. On the basis of our results, we suggest that malonyl ginsenosides should be transformed into the corresponding neutral ginsenosides during sample preparation for quality control and evaluation of P. ginseng. Then the content of six neutral ginsenosides in samples was used as the true level of total ginsenosides. The results reported here might provide useful information for accurate evaluation and quality control of P. ginseng.