CHITRAWINA MAHAGITA | Phramongkutklao College of Medicine (original) (raw)

Uploads

Papers by CHITRAWINA MAHAGITA

Research paper thumbnail of Roles of meditation on alleviation of oxidative stress and improvement of antioxidant system

PubMed, Nov 1, 2010

According to MEDLINE/Pubmed search to December 2009, the modulation effects of meditation on oxid... more According to MEDLINE/Pubmed search to December 2009, the modulation effects of meditation on oxidative stress have been increasingly investigated for acute, short and long-term effects. Both invasive and noninvasive measurements have been utilized. Long-term transcendental and Zen meditators have been showed to diminish oxidative stress seen by a reduction of lipid peroxidation and biophoton emission. Glutathione level and activity of antioxidant enzymes (catalase, superoxide dismutase, glutathione peroxidase and glutathione reductase) have been facilitated in Yoga and Sudarshan Kriya practitioners. One year of Tai Chi training has been reported to promote superoxide dismutase activity and lessen lipid peroxidation. Performing diaphragmatic breathing after exhaustive exercise has attenuated oxidative stress faster than control. These data suggest possible roles of meditation and meditation-based techniques on the decrease of oxidative stress which may assist to prevent and/or alleviate deterioration of related diseases. However, further research needs to elucidate the cellular and molecular mechanisms which remain challenge to accomplish.

Research paper thumbnail of Roles of meditation on alleviation of oxidative stress and improvement of antioxidant system

Journal of the Medical Association of Thailand = Chotmaihet thangphaet, 2010

According to MEDLINE/Pubmed search to December 2009, the modulation effects of meditation on oxid... more According to MEDLINE/Pubmed search to December 2009, the modulation effects of meditation on oxidative stress have been increasingly investigated for acute, short and long-term effects. Both invasive and noninvasive measurements have been utilized. Long-term transcendental and Zen meditators have been showed to diminish oxidative stress seen by a reduction of lipid peroxidation and biophoton emission. Glutathione level and activity of antioxidant enzymes (catalase, superoxide dismutase, glutathione peroxidase and glutathione reductase) have been facilitated in Yoga and Sudarshan Kriya practitioners. One year of Tai Chi training has been reported to promote superoxide dismutase activity and lessen lipid peroxidation. Performing diaphragmatic breathing after exhaustive exercise has attenuated oxidative stress faster than control. These data suggest possible roles of meditation and meditation-based techniques on the decrease of oxidative stress which may assist to prevent and/or allevi...

Research paper thumbnail of 4-Hydroxyacetophenone-Induced Choleresis in Rats is Mediated by the Mrp2-Dependent Biliary Secretion of Its Glucuronide Conjugate

PurposeThe present study examined the underlying mechanism by which 4-hydroxyacetophenone (4-HA),... more PurposeThe present study examined the underlying mechanism by which 4-hydroxyacetophenone (4-HA), a bioactive compound found in several medicinal herbs, exerts its potent stimulatory effects on hepatic bile secretion.MethodsBile flow, and biliary excretion of 4-HA, its metabolites, and inorganic electrolytes was examined in both normal Wistar rats and in TR- Wistar rats that have a congenital defect in the multidrug resistance-associated protein-2, Mrp2/Abcc2. The effects of 4-HA were also examined in animals treated with buthionine sulfoximine to decrease hepatic glutathione (GSH) levels.ResultsIn normal rats, 4-HA dramatically increased bile flow rate, whereas it failed to exert a choleretic effect in TR- rats. This choleresis was not explained by increased biliary output of Na+, K+, Cl− or HCO3−, or by increased biliary GSH excretion. Depletion of hepatic GSH with buthionine sulfoximine had no effect on the 4-HA-induced choleresis. HPLC analysis revealed that a single major compo...

Research paper thumbnail of A protective effect of Curcuma comosa Roxb. on bone loss in estrogen deficient mice

Lancet, 2011

Ethnopharmacological relevanceCurcuma comosa Roxb. or Wan chak motluk is an indigenous medicinal ... more Ethnopharmacological relevanceCurcuma comosa Roxb. or Wan chak motluk is an indigenous medicinal herb and has traditionally been used among postmenopausal women for relief of unpleasant menopausal symptoms.

Research paper thumbnail of Phloracetophenone-Induced Choleresis in Rats is Mediated Through Mrp2

Research paper thumbnail of Human organic anion transporter 1B1 and 1B3 function as bidirectional carriers and do not mediate GSH-bile acid cotransport

American Journal of Physiology-Gastrointestinal and Liver Physiology, Jul 1, 2007

Organic anion transporting polypeptides (OATP/SLCO) are generally believed to function as electro... more Organic anion transporting polypeptides (OATP/SLCO) are generally believed to function as electroneutral anion exchangers, but direct evidence for this contention has only been provided for one member of this large family of genes, rat Oatp1a1/Oatp1 (Slco1a1). In contrast, a recent study has indicated that human OATP1B3/OATP-8 (SLCO1B3) functions as a GSH-bile acid cotransporter. The present study examined the transport mechanism and possible GSH requirement of the two members of this protein family that are expressed in relatively high levels in the human liver, OATP1B3/OATP-8 and OATP1B1/OATP-C (SLCO1B1). Uptake of taurocholate in Xenopus laevis oocytes expressing either OATP1B1/OATP-C, OATP1B3/OATP-8, or polymorphic forms of OATP1B3/OATP-8 (namely, S112A and/or M233I) was cis-inhibited by taurocholate and estrone sulfate but was unaffected by GSH. Likewise, taurocholate and estrone sulfate transport were trans-stimulated by estrone sulfate and taurocholate but were unaffected by GSH. OATP1B3/OATP-8 also did not mediate GSH efflux or GSH-taurocholate cotransport out of cells, indicating that GSH is not required for transport activity. In addition, estrone sulfate uptake in oocytes microinjected with OATP1B3/OATP-8 or OATP1B1/OATP-C cRNA was unaffected by depolarization of the membrane potential or by changes in pH, suggesting an electroneutral transport mechanism. Overall, these results indicate that OATP1B3/ OATP-8 and OATP1B1/OATP-C most likely function as bidirectional facilitated diffusion transporters and that GSH is not a substrate or activator of their transport activity. membrane transport; anion exchange; driving force; glutathione; organic solute transporters THE CLEARANCE of endogenous substances and xenobiotics from blood is one of the vital functions of the liver. This elaborate system requires specific uptake, biotransformation, and excretion mechanisms. Hepatic uptake is mediated in large part by three types of transporters: the sodium-taurocholate cotransporter (SLC10) (9), organic anion or cation transporters (SLC22A) (6, 15), and organic anion transporting polypeptides (OATP/SLCO) (12, 20). Members of the OATP/SLCO family of solute carriers function as transporters for a large variety of amphipathic organic compounds. These proteins mediate Na ϩ-and ATP-independent transport of bile salts, steroids, thyroid hormones, anionic peptides, drugs, and xenobiotics (7, 8

Research paper thumbnail of Roles of meditation on alleviation of oxidative stress and improvement of antioxidant system

Journal of the Medical Association of Thailand Chotmaihet Thangphaet, Nov 1, 2010

According to MEDLINE/Pubmed search to December 2009, the modulation effects of meditation on oxid... more According to MEDLINE/Pubmed search to December 2009, the modulation effects of meditation on oxidative stress have been increasingly investigated for acute, short and long-term effects. Both invasive and noninvasive measurements have been utilized. Long-term transcendental and Zen meditators have been showed to diminish oxidative stress seen by a reduction of lipid peroxidation and biophoton emission. Glutathione level and activity of antioxidant enzymes (catalase, superoxide dismutase, glutathione peroxidase and glutathione reductase) have been facilitated in Yoga and Sudarshan Kriya practitioners. One year of Tai Chi training has been reported to promote superoxide dismutase activity and lessen lipid peroxidation. Performing diaphragmatic breathing after exhaustive exercise has attenuated oxidative stress faster than control. These data suggest possible roles of meditation and meditation-based techniques on the decrease of oxidative stress which may assist to prevent and/or alleviate deterioration of related diseases. However, further research needs to elucidate the cellular and molecular mechanisms which remain challenge to accomplish.

Research paper thumbnail of Dialogue Workshop Helps Improve Residents' Understanding of Others

Royal Thai Army Medical Journal, 2019

Introduction: Dialogue is a free flow communication technique that helps the stream of meaning to... more Introduction: Dialogue is a free flow communication technique that helps the stream of meaning to flow among people. It makes shared meaning or new understanding to hold people or society together. Four principles of dialogue are 1) deep listening, 2) respect, 3) suspending judgments, and 4) voicing. The dialogue workshop is a fundamental practice in transformative learning and contemplative education. Objective: This study aimed to analyze the content of written reflections of participants after attending the dialogue workshop. Methods: In academic year 2018, Phramongkutklao Hospital arranged a dialogue workshop for first-year medical residents in the theme of communication skills. Voluntary participants were 49 first-year medical residents of Phramongkutklao Hospital. The 2.5-hour dialogue workshop included orientation, icebreaking, learning zone, the practice of dialogue both in pairs and in groups, and written reflections. Expert facilitators enhanced mindfulness practice throughout the workshop. The four reflection topics are: 1) what I have learned from the workshop, 2) outstanding feelings and reasons, 3) perspective shift or transformation and 4) applications. Then two researchers independently analyzed reflection contents before making discussion and conclusion together. Results: Firstly, participants learned the dialogue technique and its benefits in understanding others and themselves. Secondly, the obvious feelings during the workshop were understanding of others and themselves, and lessening ego and peace. Thirdly, the changes that occurred were better awareness of listening, and improvement of perspectives on others and themselves. Lastly, participants can apply the dialogue with patients, patients' relatives, coworkers, and people they felt close to. Conclusion: The dialogue workshop helped to improve residents' understanding of others and themselves, and transformed perspectives in a positive direction. This study benefitted the medical residency program of Phramongkutklao Hospital. Also, it provided scientific data for medical education and suggested the possibility to apply a dialogue workshop to cultivate medical learners in well-rounded aspects.

Research paper thumbnail of Roles of meditation on alleviation of oxidative stress and improvement of antioxidant system

PubMed, Nov 1, 2010

According to MEDLINE/Pubmed search to December 2009, the modulation effects of meditation on oxid... more According to MEDLINE/Pubmed search to December 2009, the modulation effects of meditation on oxidative stress have been increasingly investigated for acute, short and long-term effects. Both invasive and noninvasive measurements have been utilized. Long-term transcendental and Zen meditators have been showed to diminish oxidative stress seen by a reduction of lipid peroxidation and biophoton emission. Glutathione level and activity of antioxidant enzymes (catalase, superoxide dismutase, glutathione peroxidase and glutathione reductase) have been facilitated in Yoga and Sudarshan Kriya practitioners. One year of Tai Chi training has been reported to promote superoxide dismutase activity and lessen lipid peroxidation. Performing diaphragmatic breathing after exhaustive exercise has attenuated oxidative stress faster than control. These data suggest possible roles of meditation and meditation-based techniques on the decrease of oxidative stress which may assist to prevent and/or alleviate deterioration of related diseases. However, further research needs to elucidate the cellular and molecular mechanisms which remain challenge to accomplish.

Research paper thumbnail of Roles of meditation on alleviation of oxidative stress and improvement of antioxidant system

Journal of the Medical Association of Thailand = Chotmaihet thangphaet, 2010

According to MEDLINE/Pubmed search to December 2009, the modulation effects of meditation on oxid... more According to MEDLINE/Pubmed search to December 2009, the modulation effects of meditation on oxidative stress have been increasingly investigated for acute, short and long-term effects. Both invasive and noninvasive measurements have been utilized. Long-term transcendental and Zen meditators have been showed to diminish oxidative stress seen by a reduction of lipid peroxidation and biophoton emission. Glutathione level and activity of antioxidant enzymes (catalase, superoxide dismutase, glutathione peroxidase and glutathione reductase) have been facilitated in Yoga and Sudarshan Kriya practitioners. One year of Tai Chi training has been reported to promote superoxide dismutase activity and lessen lipid peroxidation. Performing diaphragmatic breathing after exhaustive exercise has attenuated oxidative stress faster than control. These data suggest possible roles of meditation and meditation-based techniques on the decrease of oxidative stress which may assist to prevent and/or allevi...

Research paper thumbnail of 4-Hydroxyacetophenone-Induced Choleresis in Rats is Mediated by the Mrp2-Dependent Biliary Secretion of Its Glucuronide Conjugate

PurposeThe present study examined the underlying mechanism by which 4-hydroxyacetophenone (4-HA),... more PurposeThe present study examined the underlying mechanism by which 4-hydroxyacetophenone (4-HA), a bioactive compound found in several medicinal herbs, exerts its potent stimulatory effects on hepatic bile secretion.MethodsBile flow, and biliary excretion of 4-HA, its metabolites, and inorganic electrolytes was examined in both normal Wistar rats and in TR- Wistar rats that have a congenital defect in the multidrug resistance-associated protein-2, Mrp2/Abcc2. The effects of 4-HA were also examined in animals treated with buthionine sulfoximine to decrease hepatic glutathione (GSH) levels.ResultsIn normal rats, 4-HA dramatically increased bile flow rate, whereas it failed to exert a choleretic effect in TR- rats. This choleresis was not explained by increased biliary output of Na+, K+, Cl− or HCO3−, or by increased biliary GSH excretion. Depletion of hepatic GSH with buthionine sulfoximine had no effect on the 4-HA-induced choleresis. HPLC analysis revealed that a single major compo...

Research paper thumbnail of A protective effect of Curcuma comosa Roxb. on bone loss in estrogen deficient mice

Lancet, 2011

Ethnopharmacological relevanceCurcuma comosa Roxb. or Wan chak motluk is an indigenous medicinal ... more Ethnopharmacological relevanceCurcuma comosa Roxb. or Wan chak motluk is an indigenous medicinal herb and has traditionally been used among postmenopausal women for relief of unpleasant menopausal symptoms.

Research paper thumbnail of Phloracetophenone-Induced Choleresis in Rats is Mediated Through Mrp2

Research paper thumbnail of Human organic anion transporter 1B1 and 1B3 function as bidirectional carriers and do not mediate GSH-bile acid cotransport

American Journal of Physiology-Gastrointestinal and Liver Physiology, Jul 1, 2007

Organic anion transporting polypeptides (OATP/SLCO) are generally believed to function as electro... more Organic anion transporting polypeptides (OATP/SLCO) are generally believed to function as electroneutral anion exchangers, but direct evidence for this contention has only been provided for one member of this large family of genes, rat Oatp1a1/Oatp1 (Slco1a1). In contrast, a recent study has indicated that human OATP1B3/OATP-8 (SLCO1B3) functions as a GSH-bile acid cotransporter. The present study examined the transport mechanism and possible GSH requirement of the two members of this protein family that are expressed in relatively high levels in the human liver, OATP1B3/OATP-8 and OATP1B1/OATP-C (SLCO1B1). Uptake of taurocholate in Xenopus laevis oocytes expressing either OATP1B1/OATP-C, OATP1B3/OATP-8, or polymorphic forms of OATP1B3/OATP-8 (namely, S112A and/or M233I) was cis-inhibited by taurocholate and estrone sulfate but was unaffected by GSH. Likewise, taurocholate and estrone sulfate transport were trans-stimulated by estrone sulfate and taurocholate but were unaffected by GSH. OATP1B3/OATP-8 also did not mediate GSH efflux or GSH-taurocholate cotransport out of cells, indicating that GSH is not required for transport activity. In addition, estrone sulfate uptake in oocytes microinjected with OATP1B3/OATP-8 or OATP1B1/OATP-C cRNA was unaffected by depolarization of the membrane potential or by changes in pH, suggesting an electroneutral transport mechanism. Overall, these results indicate that OATP1B3/ OATP-8 and OATP1B1/OATP-C most likely function as bidirectional facilitated diffusion transporters and that GSH is not a substrate or activator of their transport activity. membrane transport; anion exchange; driving force; glutathione; organic solute transporters THE CLEARANCE of endogenous substances and xenobiotics from blood is one of the vital functions of the liver. This elaborate system requires specific uptake, biotransformation, and excretion mechanisms. Hepatic uptake is mediated in large part by three types of transporters: the sodium-taurocholate cotransporter (SLC10) (9), organic anion or cation transporters (SLC22A) (6, 15), and organic anion transporting polypeptides (OATP/SLCO) (12, 20). Members of the OATP/SLCO family of solute carriers function as transporters for a large variety of amphipathic organic compounds. These proteins mediate Na ϩ-and ATP-independent transport of bile salts, steroids, thyroid hormones, anionic peptides, drugs, and xenobiotics (7, 8

Research paper thumbnail of Roles of meditation on alleviation of oxidative stress and improvement of antioxidant system

Journal of the Medical Association of Thailand Chotmaihet Thangphaet, Nov 1, 2010

According to MEDLINE/Pubmed search to December 2009, the modulation effects of meditation on oxid... more According to MEDLINE/Pubmed search to December 2009, the modulation effects of meditation on oxidative stress have been increasingly investigated for acute, short and long-term effects. Both invasive and noninvasive measurements have been utilized. Long-term transcendental and Zen meditators have been showed to diminish oxidative stress seen by a reduction of lipid peroxidation and biophoton emission. Glutathione level and activity of antioxidant enzymes (catalase, superoxide dismutase, glutathione peroxidase and glutathione reductase) have been facilitated in Yoga and Sudarshan Kriya practitioners. One year of Tai Chi training has been reported to promote superoxide dismutase activity and lessen lipid peroxidation. Performing diaphragmatic breathing after exhaustive exercise has attenuated oxidative stress faster than control. These data suggest possible roles of meditation and meditation-based techniques on the decrease of oxidative stress which may assist to prevent and/or alleviate deterioration of related diseases. However, further research needs to elucidate the cellular and molecular mechanisms which remain challenge to accomplish.

Research paper thumbnail of Dialogue Workshop Helps Improve Residents' Understanding of Others

Royal Thai Army Medical Journal, 2019

Introduction: Dialogue is a free flow communication technique that helps the stream of meaning to... more Introduction: Dialogue is a free flow communication technique that helps the stream of meaning to flow among people. It makes shared meaning or new understanding to hold people or society together. Four principles of dialogue are 1) deep listening, 2) respect, 3) suspending judgments, and 4) voicing. The dialogue workshop is a fundamental practice in transformative learning and contemplative education. Objective: This study aimed to analyze the content of written reflections of participants after attending the dialogue workshop. Methods: In academic year 2018, Phramongkutklao Hospital arranged a dialogue workshop for first-year medical residents in the theme of communication skills. Voluntary participants were 49 first-year medical residents of Phramongkutklao Hospital. The 2.5-hour dialogue workshop included orientation, icebreaking, learning zone, the practice of dialogue both in pairs and in groups, and written reflections. Expert facilitators enhanced mindfulness practice throughout the workshop. The four reflection topics are: 1) what I have learned from the workshop, 2) outstanding feelings and reasons, 3) perspective shift or transformation and 4) applications. Then two researchers independently analyzed reflection contents before making discussion and conclusion together. Results: Firstly, participants learned the dialogue technique and its benefits in understanding others and themselves. Secondly, the obvious feelings during the workshop were understanding of others and themselves, and lessening ego and peace. Thirdly, the changes that occurred were better awareness of listening, and improvement of perspectives on others and themselves. Lastly, participants can apply the dialogue with patients, patients' relatives, coworkers, and people they felt close to. Conclusion: The dialogue workshop helped to improve residents' understanding of others and themselves, and transformed perspectives in a positive direction. This study benefitted the medical residency program of Phramongkutklao Hospital. Also, it provided scientific data for medical education and suggested the possibility to apply a dialogue workshop to cultivate medical learners in well-rounded aspects.