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Yeo W, Yeo H, Lai K, Pang E, Mo F. P248 Evaluation of potential factors related to chemotherapy-induced nausea and vomiting (CINV) among Chinese breast cancer patients: individual patient data analysis. Breast 2023. [DOI: 10.1016/s0960-9776(23)00366-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/17/2023] Open
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2
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Yeo H, Balagiannis DP, Koek JH, Parker JK. Comparison of Odorants in Beef and Chicken Broth-Focus on Thiazoles and Thiazolines. Molecules 2022; 27:molecules27196712. [PMID: 36235248 PMCID: PMC9570687 DOI: 10.3390/molecules27196712] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/27/2022] [Revised: 09/20/2022] [Accepted: 09/21/2022] [Indexed: 11/05/2022]
Abstract
The shift in consumer landscape towards vegan, vegetarian and flexitarian diets has created an unprecedented challenge in creating meat aroma from plant-based alternatives. The search for potential vegan solutions has thus led to a renewed interest in authentic meat flavour profiles. To gain a better understanding of the qualitative odour differences between boiled beef and boiled chicken, aroma extracts were isolated using Likens-Nickerson simultaneous distillation-extraction (SDE), selected expressly because the in-situ heating of the sample facilitates the capture of aroma intermediates during the cooking process, thereby mimicking the cooking of meat in stocks and stews. The extracts were then analysed by Gas Chromatography-Mass Spectrometry (GC-MS) and GC-Olfactometry (GC-O). Most of the volatiles identified in this study were sulfur-containing compounds, such as sulfides, thiols, mercaptoaldehydes and mercaptoketones, which are derived from the Maillard reaction. Meanwhile, lipid oxidation results in the formation of unsaturated aldehydes, such as alkenals and alkadienals. Families of thiazoles and 3-thiazolines were found in the extracts. Two novel 3-thiazolines (5-ethyl-2,4-dimethyl-3-thiazoline and 2-ethyl-4,5-dimethyl-3-thiazoline) which may also contribute to the meaty aroma were identified in this work and synthesised from their respective aldehyde and mercaptoketone precursors.
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Affiliation(s)
- Huiqi Yeo
- Department of Food and Nutritional Sciences, University of Reading, Whiteknights, Reading RG6 6DZ, UK
| | - Dimitrios P. Balagiannis
- Department of Food and Nutritional Sciences, University of Reading, Whiteknights, Reading RG6 6DZ, UK
| | - Jean H. Koek
- Foods Innovation Centre Unilever, Bronland 14, 6708 WH Wageningen, The Netherlands
| | - Jane K. Parker
- Department of Food and Nutritional Sciences, University of Reading, Whiteknights, Reading RG6 6DZ, UK
- Correspondence:
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3
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Yu Y, Yeo H, Kang S. The influence of depression on health utility value in patients with gynecologic cancer : A comparison with physical symptoms and performance status. Gynecol Oncol 2019. [DOI: 10.1016/j.ygyno.2019.04.646] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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4
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Yeo H, Abelson J, Milsom J, Sharma S, Sedrakyan A. Short-term cost-effectiveness of colonic stenting is lost at 90-day follow-up in patients with malignant large bowel obstruction. Int J Surg 2016. [DOI: 10.1016/j.ijsu.2016.11.061] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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5
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Kiely M, Sharma S, Sedrakyan A, Yoo J, Yeo H, Abelson J, Milsom J. 3-Year outcomes and cost-savings of combined endoscopic laparoscopic surgery (CELS) for benign colon polyps. Int J Surg 2016. [DOI: 10.1016/j.ijsu.2016.11.062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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6
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Chen M, Yeo H, Roman S, Sosa J. Life Events of Surgical Residents: Discrepancies Persist Between Women and Men. J Surg Res 2013. [DOI: 10.1016/j.jss.2012.10.683] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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7
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Yeo H, Kim HW, Mo J, Lee D, Han S, Hong S, Koh MJ, Sun W, Choi S, Rhyu IJ, Kim H, Lee HW. Developmental expression and subcellular distribution of synaptotagmin 11 in rat hippocampus. Neuroscience 2012; 225:35-43. [PMID: 22960622 DOI: 10.1016/j.neuroscience.2012.08.062] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2012] [Revised: 08/21/2012] [Accepted: 08/29/2012] [Indexed: 11/18/2022]
Abstract
Synaptotagmins are required for Ca(2+)-dependent membrane-trafficking in either neuronal synaptic vesicles or cellular membranes. Previous reports suggested that the synaptotagmin 11 (syt11) gene is involved in the development of schizophrenia based on the genomic analysis of patients. Parkin protein binds to the C2 domains of Syt11 which leads to the polyubiquitination of Syt11. However, where and how Syt11 performs its role in the brain is largely unknown. Here, we report that Syt11 is expressed mainly in the brain. In addition, exogenously expressed Syt11 in HEK293 cells can form higher molecular weight complex via its transmembrane domain. Also, Syt11 is targeted to both dendrite and axon compartments. Immunocytochemistry showed that Syt11 is juxtaposed to postsynaptic markers in both excitatory and inhibitory synapses. Both neuroligin 1 and 2, which are postsynaptic cell adhesion molecules and differentially induce excitatory and inhibitory presynapses, respectively, recruit Syt11 in neuron coculture. Immunogold electron microscopy analysis revealed that Syt11 exists mainly in presynaptic neurotransmitter vesicles and plasma membrane, and rarely in postsynaptic sites. These results suggest that Syt11 may contribute to the regulation of neurotransmitter release in the excitatory and inhibitory presynapses, and postsynapse-targeted membrane trafficking in dendrites.
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Affiliation(s)
- H Yeo
- Department of Anatomy and Division of Brain Korea 21 Biomedical Science, College of Medicine, Korea University, 126-1, 5-Ka, Anam-Dong, Seongbuk-Gu, Seoul 136-705, Republic of Korea
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8
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Wong R, Sullivan M, Yeo H, Roman S, Sosa J. Race and Surgical Residency: Results from A National Survey of 4,339 US General Surgery Residents. J Surg Res 2012. [DOI: 10.1016/j.jss.2011.11.613] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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9
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Sullivan M, Yeo H, Roman S, Sosa J. Striving for Work-Life Balance: Effect of Marriage and Children on the Experience of 4402 U.S. General Surgery Residents. J Surg Res 2012. [DOI: 10.1016/j.jss.2011.11.612] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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10
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Sue G, Bucholz E, Yeo H, Roman S, Bell R, Sosa J. Dedicated Research During General Surgery Residency is a Vulnerable Time: Results of a National Survey. J Surg Res 2011. [DOI: 10.1016/j.jss.2010.11.832] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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11
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Kim S, Shim E, Yeo H, Hong Y, Kim D, Kim T, Kim J, Im S, Jung K, Chang H. KRAS mutation status and clinical outcome of preoperative chemoradiation (CRT) with or without cetuximab in locally advanced rectal cancer (LARC): A pooled analysis of two phase II trials. J Clin Oncol 2010. [DOI: 10.1200/jco.2010.28.15_suppl.3650] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Abstract
A new triterpene lactone named patrinolide A (1) has been isolated from the roots of Patrinia scabiosaefolia (Valerianaceae). Its structure was determined to be 11beta,21beta-dihydroxy-3-oxooleanan-28,13beta-olide on the basis of spectral analysis, including 2D-NMR techniques. Key words: Patrinia scabiosaefolia, Valerianaceae, Lactone, Patrinolide, 11beta,21beta-dihydroxy-3-oxooleanan-28,13beta-olide.
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Affiliation(s)
- M Y Yang
- College of Pharmacy, Seoul National University, Seoul 151-742, Korea
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Lee MK, Yeo H, Kim J, Kim YC. Protection of rat hepatocytes exposed to CCl4 in-vitro by cynandione A, a biacetophenone from Cynanchum wilfordii. J Pharm Pharmacol 2000; 52:341-5. [PMID: 10757424 DOI: 10.1211/0022357001773896] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
To identify hepatoprotective agents from plant sources we use primary cultures of rat hepatocytes injured by CCl4. The hepatoprotective agents are the compounds that mitigate the injury caused by CCl4. Using this system we have investigated the biochemical mechanisms involved in the hepatoprotective activity of cynandione A, a biacetopherone, isolated from the roots of Cynanchum wilfordii Hemsley (Asclepiadaceae). Cynandione A (50 microM) significantly reduced (approximately 50%) the release into the culture medium of glutamic pyruvic transaminase and sorbitol dehydrogenase from the primary cultures of rat hepatocytes exposed to CCl4. Glutathione, superoxide dismutase, catalase and glutathione reductase play important roles in the cellular defence against oxidative stress. Cynandione A appeared to protect primary cultured rat hepatocytes exposed to CCl4 from significant drops in the levels of each of these four specific markers. Cynandione A also ameliorated lipid peroxidation by up to 50% as demonstrated by a reduction in the production of malondialdehyde. These results suggest that cynandione A protected the hepatocytes from CCl4-injury by maintaining the level of glutathione and by inhibiting the production of malondialdehyde, due to its radical scavenging properties.
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Affiliation(s)
- M K Lee
- College of Pharmacy, Seoul National University, Korea
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Abstract
Oxidative stress has been implicated as a primary cause of neuronal death in certain neurodegenerative disorders and in aging brains. Natural products have been used in Asian societies for centuries for treating such neurodegenerative disorders as senile dementia. In an effort to identify active neuroprotective compounds from these products, we have employed cultures of rat cortical neurons as our screening system. A methanolic extract from dried roots of Cynanchum wilfordii Hemsley (Asclepiadaceae) significantly mitigated the neurotoxicity induced by H2O2 in this screening system. Activity-guided fractionation using several chromatographic techniques resulted in the isolation of the neuroprotective compound, cynandione A, a biacetophenone. At a concentration of 50 microM, cynandione A significantly reduced neurotoxicity induced by H2O2. Cynandione A significantly attenuated decreases in levels of glutathione, superoxide dismutase, and other enzymes that participate in the cellular defense against oxidative stress. Furthermore, cynandione A alleviated neurotoxicity induced by the excitotoxic neurotransmitter, L-glutamate, the neurotoxicity induced by kainate, but not that mediated by N-methyl-D-aspartate. Cynandione A was demonstrated to be a natural antioxidant as it facilitated the breakdown of hydrogen peroxide in vitro; however, no mechanism was uncovered to explain its neuroprotectant effects against glutamate and kainate. Therefore, cynandione A may be efficacious in protecting neurons from oxidative stress mediated via activation of alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionate/kainate receptors since it exerted significant neuroprotective effects on cultured cortical neurons.
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Affiliation(s)
- M K Lee
- College of Pharmacy, Seoul National University, Korea
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Abstract
The oxidative dimerization of ferulic acid has been carried out using horse-radish peroxidase as catalyst to give a dihydrobenzofuran neolignan (1), the structure of which was elucidated as (2SR,3RS)-2,3-dihydro-2-(4-hydroxy-3-methoxyphenyl)-3-n-buto xycarbonyl-5-(2E-carboxyethenyl)-7-methoxybenzofuran by spectroscopic analyses. This compound showed more potent cytotoxicity against several tumor cell lines than the starting material.
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Affiliation(s)
- H Yeo
- College of Pharmacy, Seoul National University, Korea
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16
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Abstract
Bioactivity-guided fractionation of the CHCl3 extract from hooks of Uncaria rhynchophylla led to the isolation of two triterpene esters, namely uncarinic acids A (1) and B (2). Their structures were established by spectroscopic and chemical methods. These compounds inhibited phospholipase Cgamma1 with IC50 values of 35.66 and 44.55 microM, respectively.
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Affiliation(s)
- J S Lee
- College of Pharmacy, Seoul National University, Korea
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Abstract
Three new steroidal glycosides named cynascyrosides A-C were isolated from the roots of Cynanchum ascyrifolium. The structures of these compounds were determined on the basis of spectroscopic and chemical evidence as cynajapogenin A 3-O-alpha-D-oleandropyranosyl-(1-->4)-beta-L-cymaropyranosyl -(1-->4)-beta-D- digitoxopyranoside; cynajapogenin A 3-O-beta-D-glucopyranosyl-(1-->4)-alpha-L-cymaropyranosyl- (1-->4)-beta-L-cymaropyranosyl-(1-->4)-beta-L-cymaropyranoside+ ++; cynajapogenin A 3-O-beta-D-glucopyranosyl-(1-->4)-alpha-L-cymaropyranosyl- (1-->4)-beta-D-digitoxopyranosyl-(1-->4)-beta-L-cymaropyranosid e.
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Affiliation(s)
- H Yeo
- College of Pharmacy, Seoul National University, Korea
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18
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Donnelly WJ, Kobayashi A, Freeman MAR, Chin TW, Yeo H, West M, Scott G. RADIOLOGICAL AND SURVIVAL COMPARISON OF FOUR METHODS OF FIXATION OF A PROXIMAL FEMORAL STEM. ACTA ACUST UNITED AC 1997. [DOI: 10.1302/0301-620x.79b3.0790351] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
We compared the radiological appearances and survival of four methods of fixation of a femoral stem in 538 hips after follow-up for five or ten years. The fixation groups were: 1) press-fit shot-blasted smooth Ti-Al-V stem; 2) press-fit shot-blasted proximally ridged stem; 3) proximal hydroxyapatite (HA) coating; and 4) cementing. Survival analysis at five to ten years showed better results in the HA-coated (100% at five to six years) and cemented stems (100% at 5 to 6 years) than in the two press-fit groups. There was a higher mean rate of migration in the smooth and ridged Ti-Al-V shot-blasted press-fit groups (0.8 mm/year and 0.6 mm/year, respectively) when compared with the HA-coated and cemented prostheses (both 0.3 mm/year). More radiolucent lines and osteolytic lesions were seen in the press-fit groups than in either the HA-coated or cemented implants, with a trend for a lower incidence of both in the HA compared with the cemented group. Proximal osteopenia increased in the press-fit and cemented prostheses with time, but did not do so in the HA group. There was a higher incidence of resorption of the femoral neck with time in the cemented group than in the other three. We conclude that the HA and the cemented interfaces both provide secure fixation with a trend in favour of HA. The cemented prosthesis meets the suggested National Institutes of Health definition of ‘efficacious’ at ten years.
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Affiliation(s)
- W. J. Donnelly
- The Princess Alexandra Hospital, Ipswich Road, Woolloongabba, Bris-bane 4011, Australia
| | - A. Kobayashi
- Department of Orthopaedic Surgery, Osaka City University Medical School, 1-4-54 Asahi-machi, Abeno-ku, Osaka 545, Japan
| | - M. A. R. Freeman
- Bone and Joint Research Unit, The Royal London Hospital Medical College, 25-29 Ashfield Street, London E1 2AD, UK
| | - T. W. Chin
- Department of Orthopaedic Surgery, Alexandra Hospital, Singapore 159964
| | - H. Yeo
- Bone and Joint Research Unit, The Royal London Hospital Medical College, 25-29 Ashfield Street, London E1 2AD, UK
| | - M. West
- Bone and Joint Research Unit, The Royal London Hospital Medical College, 25-29 Ashfield Street, London E1 2AD, UK
| | - G. Scott
- Bone and Joint Research Unit, The Royal London Hospital Medical College, 25-29 Ashfield Street, London E1 2AD, UK
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Donnelly WJ, Kobayashi A, Freeman MA, Chin TW, Yeo H, West M, Scott G. Radiological and survival comparison of four methods of fixation of a proximal femoral stem. J Bone Joint Surg Br 1997; 79:351-60. [PMID: 9180308 DOI: 10.1302/0301-620x.79b3.7060] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
We compared the radiological appearances and survival of four methods of fixation of a femoral stem in 538 hips after follow-up for five or ten years. The fixation groups were: 1) press-fit shot-blasted smooth Ti-A1-V stem; 2) press-fit shot-blasted proximally ridged stem; 3) proximal hydroxyapatite (HA) coating; and 4) cementing. Survival analysis at five to ten years showed better results in the HA-coated (100% at five to six years) and cemented stems (100% at 5 to 6 years) than in the two press-fit groups. There was a higher mean rate of migration in the smooth and ridged Ti-A1-V shot-blasted press-fit groups (0.8 mm/year and 0.6 mm/year, respectively) when compared with the HA-coated and cemented prostheses (both 0.3 mm/year). More radiolucent lines and osteolytic lesions were seen in the press-fit groups than in either the HA-coated or cemented implants, with a trend for a lower incidence of both in the HA compared with the cemented group. Proximal osteopenia increased in the press-fit and cemented prostheses with time, but did not do so in the HA group. There was a higher incidence of resorption of the femoral neck with time in the cemented group than in the other three. We conclude that the HA and the cemented interfaces both provide secure fixation with a trend in favour of HA. The cemented prosthesis meets the suggested National Institutes of Health definition of 'efficacious' at ten years.
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Affiliation(s)
- Y H Choi
- College of Pharmacy, Seoul National University, Korea
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21
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Abstract
DNA damage produces a series of oxidation products including 8-oxo-2'-deoxyguanosine and 8-oxoguanine, whose urinary excretion have been used to estimate in vivo oxidative injury. A monoclonal antibody to 8-oxoguanine was used to measure these adducts in urine taken from ill infants. In the process of this investigation we observed a large chromatographic peak that did not correspond to any of the known 8-oxoguanine adducts. A combination of liquid chromatography with electrochemical detection and gas chromatography/mass spectrometry allowed isolation and identification of the previously undescribed oxidation product, N2-methyl-8-oxoguanine. The excretion of this compound is increased in ill and growing infants but is also found in the urine of adult rats and humans. Experiments with allopurinol, a xanthine oxidase inhibitor, show that in humans, N2-methyl-8-oxoguanine is formed from the tRNA modified base N2-methylguanine. This is in contrast to the nonmethylated bases, which are converted to 8-oxo derivatives as a result of oxidative damage to nucleic acids and do not appear to be substrates for xanthine oxidase.
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Affiliation(s)
- H J Helbock
- Department of Molecular and Cell Biology, University of California, Berkeley 94720, USA
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Yeo H. Surgical intervention for the repair of exomphalos. Prof Nurse 1996; 11:226-8. [PMID: 8552699] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Exomphalos carries a 67% chance of other serious defects, 37% of which are life-threatening. Diagnosis in utero means parents can be counselled and offered choices of treatment. Parents need long-term support if their baby has a syndrome or other abnormalities. Babies that survive do well and most lead normal lives.
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Abstract
After observations of cloudiness in the perfusion circuit at open intracardiac operations, laboratory experiments showed a precipitate in a Hartmann's solution (compound sodium lactate solution, Ringer-lactate) and sodium bicarbonate based priming fluid used for cardiopulmonary bypass. The precipitate was found to consist of calcium carbonate crystals. The crystals were not dissolved by adding plasma proteins, nor were they sufficiently cleared from the extracorporeal circuit by a 40 microns filter in the arterial line. The crystals may embolise in microvascular beds and thus be a cause of postoperative morbidity. The practice of adding sodium bicarbonate to the pump prime may be unnecessary.
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Baker MV, Ghitgas C, Haynes RK, Hilliker AE, Lynch GJ, Sherwood GV, Yeo H. The preparation of ethyl and isopropyl dienol ethers and dienol pivalate esters from Hagemann's ester and its t-butyl analogue, and the reactions of the derived ester dienolates with electrophiles. Aust J Chem 1984. [DOI: 10.1071/ch9842037] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The preparation of ethyl
4-ethoxy-2-methylcyclohexa-1,3-diene-1-carboxyate, ethyl 4-isopropoxy-
2-methylcyclohexa-1,3-diene-1-carboxylate, t-butyl
4-isopropoxy-2-methylcyclohexa-1,3-diene-1- carboxylate, ethyl 4-(t-butylcarbonyloxy)-2-methylcyclohexa-1,3-diene-1-carboxylate,
and t-butyI 4-(t-butylcarbonyloxy)-2-methylcyclohexa-1,3-diene-1-carboxylate
from Hagemann's ester and its t-butyl analogue in the presence of diethyl or diisopropyl sulfates and sodium hydride in dimethyl
sulfoxide, or pivaloyl chloride and N,N,N',N'-tetramethylethylenediamine
in tetrahydrofuran is described. The foregoing dienol ethers and esters are
smoothly deprotonated by lithium diisopropyl-
amide in tetrahydrofuran at -78" to give the corresponding ester dienolates, which react regio- specifically with a number
of electrophiles, either a or y to the alkoxycarbonyl group of the dienol ether or ester. A number
of the products, which are generally obtained in good yields, have been hydrolysed to Hagemann's ester derivatives substituted
exclusively at C1.
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