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Tan X, Campbell IG, Palagini L, Feinberg I. High internight reliability of computer-measured NREM delta, sigma, and beta: biological implications. Biol Psychiatry 2000; 48:1010-9. [PMID: 11082476 DOI: 10.1016/s0006-3223(00)00873-8] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
BACKGROUND Computer analysis of the sleep electroencephalogram (EEG) waveforms is widely employed, but there have been no systematic studies of its reliability. METHODS The most commonly used computer methods are power spectral analysis with the fast-Fourier transform (FFT) and period amplitude analysis (PAA) with zero cross or zero first derivative half-wave measurement. We applied all three computer methods to the digitized EEG of 16 normal subjects who underwent 5 consecutive nights of baseline (placebo) recording. We evaluated the internight reliability of three non-rapid eye movement (NREM) frequency bands of special importance to sleep research: delta (0.3-3 Hz), sigma (12-15 Hz), and beta (15-23 Hz). RESULTS Both FFT and the two methods of PAA gave excellent internight reliability for delta and sigma. Even a single night of recording correlated highly (r >.9) with the 5-night mean. Beta reliability was lower but still highly significant for both the PAA and the FFT measures. CONCLUSIONS Computer-analyzed sleep EEG data are highly reliable. Period amplitude methods demonstrate that wave incidence and period as well as amplitude are reliable, indicating that the reliability of composite measures (FFT power, PAA integrated amplitude) is not solely based on individual differences in EEG amplitude. The high internight stability of NREM delta indicates that it possesses traitlike characteristics and is relatively independent of day-to-day variations in state.
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Tan X, Zhou D, Zhang Y, Jiang B. [Effects of different catechins on cell cycle arrest and induction of apoptosis in LoVo cells]. ZHONGHUA YU FANG YI XUE ZA ZHI [CHINESE JOURNAL OF PREVENTIVE MEDICINE] 2000; 34:333-5. [PMID: 11860942] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
OBJECTIVE To investigate the effects of green tea (-)-epigallocatechin-3-gallate (EGCG), (-)-epigallocatechin (EGC), (-)-epicatechin-3-gallate (ECG)and (-)-epicatechin (EC) on the cell cycle arrest and induction of apoptosis in human colon carcinoma LoVo cell line. METHODS The cytotoxicity, cell cycle arrest and apoptosis-associated alterations in morphology and biochemistry were examined using the tetrazolium salt reduction (MTT) assay, gel electrophoresis, transmission electron microscope and flow cytometry after treatment of LoVo cells with the four catechins. RESULTS Treatment of LoVo cells with EGCG and EGC resulted in the growth suppression and induction of apoptosis in a time- and concentration-dependent manner. ECG and EC, however, did not have the same effects. In addition, the four catechins had different effects on the cell cycle of LoVo cells. Treatment with EGCG, EGC and ECG caused LoVo cells arrest at G1 phase in the cell cycle progression, whereas EC resulted in an arrest at S phase. CONCLUSIONS The cytotoxicity of the four catechins to LoVo cells is significantly different. The difference is associated with their effects on cell cycle and induction of apoptosis in LoVo cells.
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Tan Y, Tang L, Sun X, Zhang N, Han Q, Xu M, Baranov E, Tan X, Tan X, Rashidi B, An Z, Perry AW, Hoffman RM. Total-homocysteine enzymatic assay. Clin Chem 2000; 46:1686-8. [PMID: 11017950] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
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Tan X, Hu D, Li S, Han Y, Zhang Y, Zhou D. Differences of four catechins in cell cycle arrest and induction of apoptosis in LoVo cells. Cancer Lett 2000; 158:1-6. [PMID: 10940502 DOI: 10.1016/s0304-3835(00)00445-6] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
(-)-Epigallocatechin-3-gallate (EGCG), (-)-epigallocatechin (EGC), (-)-epicatechin-3-gallate (ECG), and (-)-epicatechin (EC) were found to have different cytotoxicities to human colon carcinoma LoVo cells. EGCG and EGC suppressed the growth of LoVo cells in dose-dependent manner; ECG and EC, however, had no obvious effects. At lower concentrations, EC did seem to promote slight proliferation. Similarly, EGCG and EGC, rather than ECG and EC, were found to induce apoptosis in LoVo cells. Moreover, EGCG, EGC, and ECG arrested G(1) phase in the cell cycle progression, whereas EC resulted in S phase arrest. We suggest that there are differences in the cytotoxicities of the four catechins to LoVo cells. They exert the effects by inducing apoptosis and regulating the cell cycle.
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Hibbard MK, Kozakewich HP, Dal Cin P, Sciot R, Tan X, Xiao S, Fletcher JA. PLAG1 fusion oncogenes in lipoblastoma. Cancer Res 2000; 60:4869-72. [PMID: 10987300] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
Lipoblastomas are pediatric neoplasms resulting from transformation of adipocytes. These benign tumors are typically composed of adipose cells in different stages of maturation within a variably myxoid matrix, and they contain clonal rearrangements of chromosome band 8q12. Because lipoblastomas resemble embryonic adipose tissue, characterization of their transforming mechanisms might reveal biological pathways in physiological adipogenesis. Herein, we demonstrate that lipoblastoma chromosome 8q12 rearrangements bring about promoter-swapping events in the PLAG1 oncqgene. We show that the hyaluronic acid synthase 2 (HAS2) or collagen 1 alpha 2 (COL1A2) gene promoter regions are fused to the entire PLAG1 coding sequence in each of four lipoblastomas. PLAG1 is a developmentally regulated zinc finger gene whose tumorigenic function has been shown previously only in epithelial salivary gland cells. Our findings reveal that PLAG1 activation, presumably resulting from transcriptional up-regulation, is a central oncogenic event in lipoblastoma.
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Tan X, Shen K, Liu D, Xu X, Lang J. [The diagnostic and prognostic values of assay of serum vascular endothelial growth factor in epithelial ovarian cancer]. ZHONGGUO YI XUE KE XUE YUAN XUE BAO. ACTA ACADEMIAE MEDICINAE SINICAE 2000; 22:352-5. [PMID: 12903449] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 03/04/2023]
Abstract
OBJECTIVE To detect the level of the preoperative serum vascular endothelial growth factor (VEGF) in patients with epithelial ovarian cancer, and to evaluate the correlation between preoperative serum VEGF level and prognosis of epithelial ovarian cancer. METHODS Forty-one patients with epithelial ovarian cancer (EOC), 10 patients with borderline ovarian tumor (BOT), and 25 women with benign ovarian tumor (BET) were included as three study groups, while 20 healthy women were selected as a control group. Enzyme-linked immunosorbent assay (ELISA) was utilized to measure the serum VEGF level. RESULTS The serum VEGF levels in patients with EOC were higher than those in patients with BOT, or with BET, or those in healthy women. The median and ranges of serum VEGF levels were as follows: EOC: median 415.0 pg/ml, range 110-2,120 pg/ml; BOT: median 312.5 pg/ml, range 100-1,250 pg/ml; BET: median 170 pg/ml, range 70-925 pg/ml; healthy women: median 165 pg/ml, range 100-735 pg/ml. When median preoperative serum VEGF levels were grouped by tumor stages, histological grade of tumor cells, histological type of the tumor, lymph node involvement, and omentum involvement, significant correlations between serum levels of VEGF and histological grade, lymph node involvement and omentum involvement were found. The patients with high serum VEGF appeared to be accompanied with poor 3-year survival. CONCLUSIONS Preoperative serum VEGF levels seemed to be correlated with the malignant behavior of ovarian cancer, which might provide some prognostic value.
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Palagini L, Campbell IG, Tan X, Guazzelli M, Feinberg I. Independence of sleep EEG responses to GABAergic hypnotics: biological implications. J Psychiatr Res 2000; 34:293-300. [PMID: 11104841 DOI: 10.1016/s0022-3956(00)00019-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
GABAergic hypnotics are known to depress non-rapid eye movement delta and rapid eye movements and to stimulate non-rapid eye movement sigma (spindles) and beta EEG. This study addressed the question of whether the magnitudes of these effects are significantly correlated. Data were from a study in 16 normal subjects whose sleep was recorded for five nights under placebo and for three nights each under zolpidem (10 mg), triazolam (0.25 mg) and temazepam (30 mg). EEG was analyzed with both period-amplitude and power spectral (FFT) analysis. The magnitudes of the EEG and eye movement density responses were not significantly correlated for any of the three drugs. It is therefore unlikely that sleep responses to GABAergic drugs can be explained by the common cellular action (increased chloride conductance) of these drugs. We suggest that the sleep EEG responses are manifestations of complex (but consistent) interactions of excitation and inhibition in large brain systems although certain aspects of these responses (e.g. the different time courses of delta vs sigma and eye movement responses) may reflect molecular adaptations. A separate observation in this study was the strong traitlike characteristics of the sleep variables studied. These variables were highly correlated across nights of baseline sleep; in addition, individual differences in baseline sleep were significantly retained on the third night of temazepam administration.
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Jorm AF, Henderson AS, Jacomb PA, Christensen H, Korten AE, Rodgers B, Tan X, Easteal S. Association of smoking and personality with a polymorphism of the dopamine transporter gene: results from a community survey. AMERICAN JOURNAL OF MEDICAL GENETICS 2000; 96:331-4. [PMID: 10898910 DOI: 10.1002/1096-8628(20000612)96:3<331::aid-ajmg19>3.0.co;2-0] [Citation(s) in RCA: 80] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
In studies that used mixed volunteer samples, Lerman et al. [1999: Health Psychol 18:14-20] and Sabol et al. [1999: Health Psychol 18:7-13] reported on an association of smoking with a polymorphism of the dopamine transporter gene. We attempted to replicate this association in a nonvolunteer community sample of 861 Caucasians. No associations were found with either smoking initiation or smoking cessation. Sabol et al. [1999] also reported on an association of the dopamine transporter polymorphism with the personality trait of novelty seeking. However, we failed to find any associations with a range of personality traits, including a scale of fun seeking that correlates with novelty seeking. These negative findings suggest that either the original associations are not replicable or that any association is very small.
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Liu S, Wu X, Wang P, Huang P, Xia X, Tan X, Mei E, Hu S. [Analysis of refractive state after excimer laser photorefractive keratectomy in myopia]. YAN KE XUE BAO = EYE SCIENCE 2000; 16:143-5, 148. [PMID: 12579926] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
OBJECTIVE To evaluate refractive state after excimer laser photorefractive keratectomy (PRK) in patients with myopia. METHODS 234 cases(391 eyes) followed up for two years were divided into two groups, group I: mild and moderate myopia(< or = -6.00 D), 228 eyes; group II: High myopia(> -6.00 D), 163 eyes. The refractive state of patients at three, six, twelve and twenty-four months postoperatively were monitored. RESULTS At two years after photorefractive keratectomy (PRK), refractive regression (> -0.5 D), overcorrection(> 1.00 D), undercorrection(> 1.00 D), postoperative residual astigmatism postoperative astigmatism and hyperopia shift in group I were 1.7%, 4.4%, 5.7%, 12.8%, 7.4% and 7.5% respectively, while in high myopia group were 15.9%, 4.9%, 23.3%, 29.7%, 31.1% and 6.7% respectively. CONCLUSION The results prove that photorefractive keratectomy is an effective, precise, stable and safe method for correction of mild and moderate myopia, but insufficient for high myopia.
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Pei J, Tan X, Chen K, Li X. [Design and optimization of a centrifugal pump for CPCR]. SHENG WU YI XUE GONG CHENG XUE ZA ZHI = JOURNAL OF BIOMEDICAL ENGINEERING = SHENGWU YIXUE GONGCHENGXUE ZAZHI 2000; 17:159-63. [PMID: 12557770] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
Requirements for an optimal centrifugal pump, the vital component in the equipment for cardiopulmonary cerebral resuscitation(CPCR), have been presented. The performance of the Sarns centrifugal pump (Sarns, Inc./3M, Ann arbor, MI, U.S.A) was tested. The preliminarily optimized model for CPCR was designed according to the requirements of CPCR and to the comparison and analysis of several clinically available centrifugal pumps. The preliminary tests using the centrifugal pump made in our laboratory(Type CPCR-I) have confirmed the design and the optimization.
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Jorm AF, Henderson AS, Jacomb PA, Christensen H, Korten AE, Rodgers B, Tan X, Easteal S. Association of a functional polymorphism of the monoamine oxidase A gene promoter with personality and psychiatric symptoms. Psychiatr Genet 2000; 10:87-90. [PMID: 10994647 DOI: 10.1097/00041444-200010020-00006] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
A functional polymorphism in the promoter of the monoamine oxidase gene has recently been described by Sabol et al. This polymorphism is a strong candidate for associations with personality traits and psychiatric symptoms. We report relevant data from a general population sample of 850 Caucasian Australians. We found no associations with anxiety and depression symptoms, with personality traits that predispose to anxiety (neuroticism, behavioral inhibition, negative affect) or to a personality trait related to antisocial behavior (psychoticism).
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Tan X, Boudinot FD, Chu CK, Egron D, Perigaud C, Gosselin G, Imbach JL. Pharmacokinetics of bis(t-butyl-SATE)-AZTMP, a bispivaloylthioethyl prodrug for intracellular delivery of zidovudine monophosphate, in mice. Antivir Chem Chemother 2000; 11:203-11. [PMID: 10901291 DOI: 10.1177/095632020001100303] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
The pharmacokinetics of a bispivaloylthioethyl prodrug of zidovudine monophosphate (AZTMP), bis(t-butyl-SATE)-AZTMP, and intracellular conversion of the prodrug to AZTMP were characterized following intravenous (i.v.) and oral (p.o.) administration of the prodrug to mice. Concentrations of bis(t-butyl-SATE)-AZTMP, AZTMP and zidovudine (AZT) in blood, red blood cells, plasma, brain and lymph nodes were determined by HPLC. Following i.v. administration of bis(t-butyl-SATE)-AZTMP, concentrations of the prodrug declined rapidly with low levels of the prodrug detected until 4 h. Both bis(t-butyl-SATE)-AZTMP and AZTMP were detected in brain 3 min after dosing. AZTMP was found in both plasma and peripheral red blood cells, peaking at approximately 30 min and remaining detectable until 2 h. No AZTMP was detected in lymph nodes. Compared to the pharmacokinetics of AZT following its i.v. administration, i.v. administration of bis(t-butyl-SATE)-AZTMP produced lower peak concentrations of AZT in plasma, peripheral red blood cells, brain and lymph nodes. However, terminal half-lives of AZT were significantly prolonged following administration of the prodrug. Following p.o. administration of bis(t-butyl-SATE)-AZTMP, neither the prodrug nor AZTMP were detectable in whole blood. The conversion of AZT from bis(t-butyl-SATE)-AZTMP in plasma and peripheral red blood cells following p.o administration was 12.1% of that following i.v. administration of the prodrug. Bis(t-butyl-SATE)-AZTMP demonstrated promising potential for intracellular delivery of AZTMP. The prodrug also prolonged the retention of AZT in mice, and particularly increased delivery of AZT to the lymphatic and central nervous systems.
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Tan X, Boudinot FD. Simultaneous determination of zidovudine and its monophosphate in mouse plasma and peripheral red blood cells by high-performance liquid chromatography. JOURNAL OF CHROMATOGRAPHY. B, BIOMEDICAL SCIENCES AND APPLICATIONS 2000; 740:281-7. [PMID: 10821415 DOI: 10.1016/s0378-4347(00)00109-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Novel prodrugs for the intracellular delivery of zidovudine monophosphate (AZTMP) have recently been designed. To investigate the bioconversion and pharmacokinetic profiles of these compounds, an analytical method for the simultaneous determination of zidovudine (AZT) and AZTMP in mouse plasma and peripheral red blood cells was developed. Mouse whole blood samples were treated with TBAHS, EDTA and NaH2PO4, and separated into plasma and red blood cell portions. Samples were processed by solid-phase extraction using Bond Elut C18 cartridges. Chromatography was performed using an Hypersil ODS column and a mobile phase of 2.9% (v/v) acetonitrile and 97.1% (v/v) phosphate buffer, pH 7.50, with UV detection at 267 nm. The average extraction recoveries of AZTMP and AZT in plasma were approximately 85% and 97% over their linear ranges of 0.05-5 microg/ml and 0.125-25 microg/ml, respectively. Extraction recoveries of AZTMP and AZT from peripheral red blood cells averaged 56 and 69% over their linear ranges of 0.125-5 microg/ml and 0.125-25 microg/ml, respectively. The accuracy of the assay was 90-100%. The intra- and inter-day variations of the assay were less than 14%. The analytical method was found to be applicable, reliable and suitable for pharmacokinetic studies.
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Tan X. [Exploration on features of early medical activities of Miao nationality]. ZHONGHUA YI SHI ZA ZHI (BEIJING, CHINA : 1980) 2000; 30:106-8. [PMID: 11624636] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/17/2023]
Abstract
The Miao Minority medicine has a long history, and it originated thousands of years ago. The features of the Miao Minority medicine in the early age include all kinds of herbs which were very popular. Thus, a long-term "combination of witch and doctor" period existed in the early age of Miao Minority. This striking feature has great influence in the Miao Minority medicine, and this influence goes on until today. The Miao Minority doctors were good at external treatment in the early age. The above three points are worth studying, constituting the distinct traditional features of the Miao Minority medicine.
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Wang Y, Tan X, Cai H. [Effects of mild hypothermia on Na(+)-K+ ATPase and lipid peroxidation in canine brain tissue following cardiac arrest and resuscitation]. HUNAN YI KE DA XUE XUE BAO = HUNAN YIKE DAXUE XUEBAO = BULLETIN OF HUNAN MEDICAL UNIVERSITY 2000; 23:8-10. [PMID: 10681782] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
Abstract
The effect of mild hypothermia on Na(+)-K+ ATPase and lipid peroxidation in canine brain tissue following a 18-minute cardiac arrest and resuscitation for 8 hours were studied. Mild hypothermia improved the restoration of the activity of Na(+)-K+ ATPase, LDH, protect the activity of SOD, decrease the loss of GSH, but not completely blocked the ischemia reperfusion induced lipid peroxidation.
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Tan X, Weng W. [Efficacy of epimedium compound pills in the treatment of the aged patients with kidney deficiency syndrome of ischemic cardio-cerebral vascular diseases]. HUNAN YI KE DA XUE XUE BAO = HUNAN YIKE DAXUE XUEBAO = BULLETIN OF HUNAN MEDICAL UNIVERSITY 2000; 23:450-2. [PMID: 10682558] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
Abstract
One hundred-twenty aged patients with kidney deficiency syndrome of ischemic cardio-cerebral vascular diseases were treated with Epimedium compound granules. The results showed that after therapeutic period the total and marked effective rates were 96.7%, 39.5% respectively in treatment group. The rates of improvement were 70% in electrocardiogram of the patients with coronary heart diseases, and 75% in electro-encephalogram of the patients with cerebral arterosclerosis. The therapeutic effectiveness in treatment group was better than that in control group treated with Su-Guan-Bian. According to experimental observation, the therapeutic effectiveness was related to the facts that Epimedium compound granules lower blood lipid have anti-free radicals and adjust balance between prostacyctin I2 and thromboxane A2(TXA2/PGI2).
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Fu T, Tan X, Pei J. [Development of a control and monitor system for the cardiopulmonary cerebral resuscitation(CPCR) device]. SHENG WU YI XUE GONG CHENG XUE ZA ZHI = JOURNAL OF BIOMEDICAL ENGINEERING = SHENGWU YIXUE GONGCHENGXUE ZAZHI 2000; 17:107-10. [PMID: 10879206] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
A novel idea in developing cardiopulmonary-cerebral resuscition(CPCR) device has been developed, using a combination of membrane artificial lung(oxygenator), mild-hypothermia, and centrifugal blood pump technologies. A control system for the CPCR has been introduced, using converter control and sensor monitor, with 8031 chips as the controller. Pressure, flow rate and temperature monitors were installed in the system. Two modes of blood pump regulation have been adopted, i.e. continous flow and pulsatile flow. The in vitro evaluation tests showed that the two modes were reasonable and feasible.
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Henderson AS, Korten AE, Jorm AF, Jacomb PA, Christensen H, Rodgers B, Tan X, Easteal S. COMT and DRD3 polymorphisms, environmental exposures, and personality traits related to common mental disorders. AMERICAN JOURNAL OF MEDICAL GENETICS 2000; 96:102-7. [PMID: 10686561 DOI: 10.1002/(sici)1096-8628(20000207)96:1<102::aid-ajmg20>3.0.co;2-3] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
In a community sample of 2,327 Caucasians, we tested the hypotheses that polymorphisms in the COMT and DRD3 genes are associated with personality traits conferring vulnerability to anxiety, depression, or alcohol misuse, or with current symptoms of these; and that the association is stronger in persons who also have been exposed to stressor experiences. To conserve resources and to allow replication, the genetic analysis was undertaken in two stages. For the COMT polymorphism, no statistically significant associations were found in the first sample of 862 persons. The remainder of the sample was therefore not analysed for that gene. For the DRD3 polymorphism, those in the first sample with at least one of the Ser(9) alleles had significantly higher scores in neuroticism (p=0.006) and behavioral inhibition (p=0.003). There was a trend, failing to meet the 1% significance criterion, for those with this genotype also to have higher depression and anxiety. The groups did not differ in alcohol use. In persons with the Ser(9) allele who were also exposed to stressors, there was a higher level of depression at the 5% level; and the depression level was higher in homozygotes. But when the remainder of the sample (1,465) was analysed, none of the associations reached statistical significance. We conclude that neither the COMT nor DRD3 polymorphisms are associated with anxiety, depression, or alcohol abuse. Am. J. Med. Genet. (Neuropsychiatr. Genet.) 96:102-107, 2000
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Henderson A, Korten A, Jorm A, Jacomb P, Christensen H, Rodgers B, Tan X, Easteal S. COMT andDRD3 polymorphisms, environmental exposures, and personality traits related to common mental disorders. ACTA ACUST UNITED AC 2000. [DOI: 10.1002/(sici)1096-8628(20000207)96:1%3c102::aid-ajmg20%3e3.0.co;2-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Tan X, Grollman AP, Shibutani S. Comparison of the mutagenic properties of 8-oxo-7,8-dihydro-2'-deoxyadenosine and 8-oxo-7,8-dihydro-2'-deoxyguanosine DNA lesions in mammalian cells. Carcinogenesis 1999; 20:2287-92. [PMID: 10590221 DOI: 10.1093/carcin/20.12.2287] [Citation(s) in RCA: 92] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The comparative mutagenicity of 8-oxo-7,8-dihydro-2'-deoxyadenosine (8-oxodA) and 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG) was explored using simian kidney (COS-7) cells. Oligodeoxynucleotides ¿5'-TCCTCCT- G(1)X(2)CCTCTC or 5'-TCCTCCTX(1)G(2)CCTCTC (X = dA, dG, 8-oxodA or 8-oxodG) containing 8-oxodA or 8-oxodG positioned within codon 60 or 61 of the non-coding strand of human c-Ha-ras1 gene were inserted into a single-stranded phagemid shuttle vector. The vector was replicated in COS-7 cells and the progeny plasmids were used to transform Escherichia coli DH10B. The transformants were analyzed by oligodeoxynucleotide hybridization and DNA sequence analysis to establish the mutation frequency and specificity. When 8-oxodA was positioned at X(1), targeted A(oxo)-->C transversions were detected; the mutation frequency was 1.2%. When 8-oxodA was positioned at X(2), one targeted mutant among 416 colonies screened (an A(oxo)-->G transition) was detected. Thus, the mutation frequency and spectrum of 8-oxodA depend on the sequence context of the lesion. The mutation frequency of 8-oxodG at X(1) and X(2) was 5.2 and 6.8%, respectively. G(oxo)-->T transversions dominated the spectrum, accompanied by small numbers of G(oxo)-->A transitions and G(oxo)-->C transversions. We conclude that 8-oxodA has mutagenic potential in mammalian cells, generating A-->C transversions. However, when tested under similar conditions, the mutation frequency of 8-oxodA is at least four times lower than that of 8-oxodG.
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Tan X, Bi Y, Su Y, Yan J, Wang F. Candidate EPA, NIOSH method for determining carbon disulfide in air with capillary gas chromatography by orthogonal design. Biomed Chromatogr 1999; 13:538-42. [PMID: 10611608 DOI: 10.1002/(sici)1099-0801(199912)13:8<538::aid-bmc924>3.0.co;2-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
This paper describes a candidate NIOSH EPA method for the determination of carbon disulfide in the air of workplaces with capillary gas chromatography using an orthogonal design. This method is designed to replace the packed column of the NIOSH method with a capillary column. The first part of this work concerned the setup of the method, particularly the choice of chromatographic parameters and finding their main favorable working ranges. The second part, using the statistical method orthogonal design, focused on optimizing the GC conditions, which were: column temperature, T(c) = 90 degrees C; injector temperature, T(i) = 140 degrees C; U section detector temperature, FPDU = 160 degrees C; L section detector temperature, FPDL = 210 degrees C; flow rate of carrier gas, F(c) = 20 cm/s; split ratio = 1/70; and injection volume = 1 microL. The quality control test showed that the coefficient of intra-day variation (CV) was 2.21%. A good logarithm linear correlation between the standard solutions and their peak areas was obtained. In general, the method reported here seems a valid candidate for a NIOSH EPA method due to its high precision and accuracy.
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Cong PJ, Cao S, Sun H, Tan X, Wang RS. Determination of fluorine in UF4 by high-temperature hydrolysis. J Radioanal Nucl Chem 1999. [DOI: 10.1007/bf02347401] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Yao Z, Tong J, Tan X, Li C, Shao Z, Kim WC, vanden Hoek TL, Becker LB, Head CA, Schumacker PT. Role of reactive oxygen species in acetylcholine-induced preconditioning in cardiomyocytes. THE AMERICAN JOURNAL OF PHYSIOLOGY 1999; 277:H2504-9. [PMID: 10600875 DOI: 10.1152/ajpheart.1999.277.6.h2504] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We examined the ability of ACh to mimic ischemic preconditioning in cardiomyocytes and the role of ATP-sensitive potassium (KATP) channels and mitochondrial reactive oxygen species (ROS) in mediating this effect. Chick embryonic ventricular myocytes were studied in a flow-through chamber while flow rate, pH, PO2, and PCO2 were controlled. Cell viability was quantified with propidium iodide (5 microM), and production of ROS was measured using 2', 7'-dichlorofluorescin diacetate. Data were expressed as means +/- SE. Preconditioning with 10 min of ischemia followed by 10 min of reoxygenation or 10 min of ACh (1 mM) followed by a drug-free period before 1 h of ischemia and 3 h of reoxygenation reduced cell death to the same extent [preconditioning 19 +/- 2% (n = 6, P < 0.05) ACh 21 +/- 5% (n = 6, P < 0.05) vs controls 42 +/- 5% (n = 9)]. Like preconditioning, ACh increased ROS production threefold before ischemia [0.60 +/- 0.16 (n = 7, P < 0.05) vs. controls, 0.16 +/- 0. 03 (n = 6); arbitrary units]. Protection and increased ROS production during ACh preconditioning were abolished with 5-hydroxydecanoate (5-HD, 100 microM), a selective mitochondrial K(ATP) channel antagonist, and the thiol reductant 2-mercaptopropionyl glycine (2-MPG, 1 mM), an antioxidant [cell death: 5-HD+ACh 37 +/- 7% (n = 5), 2-MPG+ACh 47 +/- 6% (n = 6); ROS signals: 5-HD+ACh 0.09 +/- 0.03 (n = 5), 2-MPG+ACh 0.01 +/- 0.04 (n = 4)]. In addition, ACh-induced ROS signaling was blocked by the mitochondrial site III electron transport inhibitor myxothiazol (0.02 +/- 0.07, n = 5). These results demonstrate that activation of mitochondrial K(ATP) channels and increased ROS production from mitochondria are important intracellular signals that participate in ACh-induced preconditioning in cardiomyocytes.
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Wu Z, Cao J, Zhu J, Tan X. [Clinical study on keratoplasty with corneal cryopreservation]. YAN KE XUE BAO = EYE SCIENCE 1999; 15:250-2. [PMID: 12579681] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
PURPOSE To evaluate the clinical application value of the corneal cryopreservation in keratonosus. METHODS 32 patients with keratonosus treated by corneal transplantation were clinically observed. RESULTS In 32 keratonosus cases, 59.37% (19 cases) of the grafts remained transparant; in 24 corneal ulcer preforation cases, 45.83% (11 cases) of the grafts were transparent, all eyeballs(100%) were remained. CONCLUSION Corneal cryopreservation can be a practical, effective method in the treatment of keratonosus in district hospitals.
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Adams DS, Li Q, Tan X, Pero SC, Czop JK. Cloning and characterization of a family of cDNAs from human histiocyte macrophage cells encoding an arginine-rich basic protein related to the 70 kD U1-snRNP splicing factor. DNA SEQUENCE : THE JOURNAL OF DNA SEQUENCING AND MAPPING 1999; 9:205-15. [PMID: 10520751 DOI: 10.3109/10425179809105207] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
This paper describes the cloning and characterization of five cDNA members of a novel family of mRNAs, termed hm-1, isolated from human U937 macrophage cells. Two family members (clones 46 and 11) show complete mRNA features [including ribosome binding sites (RBS), polyadenylation signals, and poly(A) tails], and encode the same protein (designated HM-1), but differ substantially in their 5' untranslated regions. The three other cDNAs (clones 20, 60, and 38) appear to represent partial cDNAs. The protein sequences deduced from the five hm-1 cDNAs are identical (some truncated), except for one Trp --> Cys substitution. Full-length HM-1 is 246 amino acids long, has a predicted MW of 29431, is rich in arginine residues, has a pI of 10.25, and a mean hydrophobicity index of -1.23. HM-1 contains no obvious hydrophobic N-terminal cleavable signal sequence, and no potential N-glycosylation sites, but does contain three highly conserved motifs present in U1-70K splicing factors, and contains numerous C-terminal Arg/Asp and Arg/Glu dipeptides characteristic of "RD" family members that function as regulators of mRNA splicing. Northern hybridizations indicate that hm-1 is a family of mRNAs differentially expressed in a variety of human tissues.
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