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Chen J, Liao W, Wen H, Wu J, Yao Z. A comparison among four regimens of itraconazole treatment in onychomycosis. Mycoses 1999; 42:93-6. [PMID: 10394855 DOI: 10.1046/j.1439-0507.1999.00404.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The purpose of this study was to compare the efficacy of different dosage regimens in the management of onychomycosis with itraconazole and to determine the results of a further 1-week intermittent pulse treatment in non-cured patients. In this study, 153 patients were randomly allocated to four groups. Patients in group A were treated with daily doses of 100 mg for 3 months in the case of fingernail onychomycosis and for 4 months in the case of toenail onychomycosis. Patients in the other groups received a intermittent pulse therapy, in which the drug was taken for 1 week, then discontinued for 3 weeks, three cycles for fingernail and four cycles for toenail infection. The daily doses were 400 mg (group B), 300 mg (group C) and 200 mg (group D). After therapy, non-cured patients were treated further with one cycle in which the daily dose was 400 mg. Patients were subsequently observed for 9 months and efficacy was assessed by mycological examination and the growth of unaffected nails. At the end of the therapy, the cure rates in the four groups were 19.1% (A), 15.2% (B), 18.9% (C) and 17.9% (D), and no significant differences were found between each of B, C, D and A. At the end of the study, the cure rates were 76.2%, 91.3%, 78.4%, 28.6% respectively. The group that received further treatment had a cure rate of 55.6% at the end of the first month and of 83.3% in the second month. Drug tolerability was equally good in the four groups. Intermittent pulse therapy with a daily dose of 400 mg had the highest cure rate. Treatment of improved but non-cured patients with a dose of 400 mg intermittent pulse therapy markedly increased the cure rate. All treatment regimens were well tolerated.
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Chang BH, Liao W, Li L, Nakamuta M, Mack D, Chan L. Liver-specific inactivation of the abetalipoproteinemia gene completely abrogates very low density lipoprotein/low density lipoprotein production in a viable conditional knockout mouse. J Biol Chem 1999; 274:6051-5. [PMID: 10037685 DOI: 10.1074/jbc.274.10.6051] [Citation(s) in RCA: 104] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Conventional knockout of the microsomal triglyceride transfer protein large subunit (lMTP) gene is embryonic lethal in the homozygous state in mice. We have produced a conditional lMTP knockout mouse by inserting loxP sequences flanking exons 5 and 6 by gene targeting. Homozygous floxed mice were born live with normal plasma lipids. Intravenous injection of an adenovirus harboring Cre recombinase (AdCre1) produced deletion of exons 5 and 6 and disappearance of lMTP mRNA and immunoreactive protein in a liver-specific manner. There was also disappearance of plasma apolipoprotein (apo) B-100 and marked reduction in apoB-48 levels. Wild-type mice showed no response, and heterozygous mice, an intermediate response, to AdCre1. Wild-type mice doubled their plasma cholesterol level following a high cholesterol diet. This hypercholesterolemia was abolished in AdCre1-treated lMTP-/- mice, the result of a complete absence of very low/intermediate/low density lipoproteins and a slight reduction in high density lipoprotein. Heterozygous mice showed an intermediate lipoprotein phenotype. The rate of accumulation of plasma triglyceride following Triton WR1339 treatment in lMTP-/- mice was <10% that in wild-type animals, indicating a failure of triglyceride-rich lipoprotein production. Pulse-chase experiments using hepatocytes isolated from wild-type and lMTP-/- mice revealed a failure of apoB secretion in lMTP-/- animals. Therefore, the liver-specific inactivation of the lMTP gene completely abrogates apoB-100 and very low/intermediate/low density lipoprotein production. These conditional knockout mice are a useful in vivo model for studying the role of MTP in apoB biosynthesis and the biogenesis of apoB-containing lipoproteins.
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203
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Yi Y, Liao W, Zhao Q, Lu X. [Separation and detection of tryptophan metabolites in biological samples]. Se Pu 1999; 17:158-61. [PMID: 12549157] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/28/2023] Open
Abstract
A reversed phase HPLC method for separation and determination of the major tryptophan (TRP) metabolites in both pyrrolas pathway and TRP hydroxylase pathway, including TRP, kynurenine(KN), 3-hydroxykynurenine(3-HKN), kynurenic acid(KA), xanthurenic acid(XA), 5-hydroxytryptophan(5-HTP), 5-hydroxytryptamin(5-HT) and 5-hydroxyindoleacetic acid(5-HIAA), has been developed by sequential optimization of mobile phase based on acetate buffer and methanol. Trichloroacetic acid(TCA) was used as ion-pairing reagent to increase the retention of 3-HKN. The effects of pH and concentrations of TCA on separation were studied. Good separation can be achieved at pH 4.0-5.0 of mobile phase in less than 25 min. When TCA was not used, 3-HKN was hard to be detected in biological samples. The maximum retention of 3-HKN was obtained at pH 4.0 with mobile phase containing 50 mmol/L TCA. Combination of electrochemical (ED) and ultraviolet (UV) detection was used in which ED was responsible for detection of 3-HKN, 5-HTP, 5-HT and 5-HIAA and UV for the others. The influences of potential of ED and wavelength of UV on detection were studied. The optimization of conditions for separation and detection in different biological samples was also discussed.
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204
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Zhang C, Li H, Liao W, Yang J, Shi W. [Animal experiment of the ketamine effects on traumatic brain injury resulting from impact maxillofacial injury]. HUA XI KOU QIANG YI XUE ZA ZHI = HUAXI KOUQIANG YIXUE ZAZHI = WEST CHINA JOURNAL OF STOMATOLOGY 1999; 17:33-5. [PMID: 12539317] [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 test the effects of ketamine (KET) on traumatic brain injury resulting from impact maxillofacial injury. METHODS The rat models with middle serious traumatic brain injury were obtained by falling impaction at maxillofacial region of the rats, then the animals were treated with KET in the early stage, and the alteration of the neural function in those rats was observed at the same time. RESULTS There was obvious difference between the rats in the KET-treating groups and the control group. It took about 2 days fewer than that of the control group for rats in the KET-treating group to recover. CONCLUSION KET can shorten the recovery time of rats with brain injury resulting from impact maxillofacial injury.
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Liao W, Cao Y, Yao K. [A study on detecting the gene deletion or loss of heterozygosity by polymerase chain reaction]. HUNAN YI KE DA XUE XUE BAO = HUNAN YIKE DAXUE XUEBAO = BULLETIN OF HUNAN MEDICAL UNIVERSITY 1998; 22:109-12. [PMID: 9868048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
The authors investigated the possibility of using PCR to dsetect the deletion of gene or loss of heterozygosity (LOH) of gene in biopsies. With some aids, such as selection of PCR cycle number, choice of internal control and screening of samples, the authors detected the deletion of GSH Clone 7 in nasophryngeal carcinoma (NPC) by PCR-Southern, and successfully found one case which partially deleted GSH Clone 7. This results was confirmed by image densitometry. Through this study, an available method to detect the deletion of gene by PCR is provided.
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207
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He Q, Wu B, Liao W, Jin J. [Determination algorithms in oscillometric blood pressure measurement]. SHENG WU YI XUE GONG CHENG XUE ZA ZHI = JOURNAL OF BIOMEDICAL ENGINEERING = SHENGWU YIXUE GONGCHENGXUE ZAZHI 1998; 15:369-72. [PMID: 12552782] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
This paper discusses the method of oscillometric blood pressure determination. A new criterion for systolic pressure and diastolic pressure determination has been proposed, which is based on ratio changes of the oscillation amplitude under a wide normalized range. Primary experiment results show the new criterion is effective.
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208
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Chong S, Montello GE, Zhang A, Cantor EJ, Liao W, Xu MQ, Benner J. Utilizing the C-terminal cleavage activity of a protein splicing element to purify recombinant proteins in a single chromatographic step. Nucleic Acids Res 1998; 26:5109-15. [PMID: 9801307 PMCID: PMC147948 DOI: 10.1093/nar/26.22.5109] [Citation(s) in RCA: 165] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
A conventional affinity protein purification system often requires a separate protease to separate the target protein from the affinity tag. This paper describes a unique protein purification system in which the target protein is fused to the C-terminus of a modified protein splicing element (intein). A small affinity tag is inserted in a loop region of the endonuclease domain of the intein to allow affinity purification. Specific mutations at the C-terminal splice junction of the intein allow controllable C-terminal peptide bond cleavage. The cleavage is triggered by addition of thiols such as dithiothreitol or free cysteine, resulting in elution of the target protein while the affinity-tagged intein remains immobilized on the affinity column. This system eliminates the need for a separate protease and allows purification of a target protein without the N-terminal methionine. We have constructed general cloning vectors and demonstrated single-column purification of several proteins. In addition, we discuss several factors that may affect the C-terminal peptide bond cleavage activity.
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209
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Yao Z, Liao W, Li Z, Xu H. Cutaneous fungal infection caused by Fusarium solani. Chin Med J (Engl) 1998; 111:1054-6. [PMID: 11189218] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023] Open
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210
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Liao W, Yeung SC, Chan L. Proteasome-mediated degradation of apolipoprotein B targets both nascent peptides cotranslationally before translocation and full-length apolipoprotein B after translocation into the endoplasmic reticulum. J Biol Chem 1998; 273:27225-30. [PMID: 9765244 DOI: 10.1074/jbc.273.42.27225] [Citation(s) in RCA: 80] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
A major portion of newly synthesized apolipoprotein B (apoB) is degraded intracellularly. This degradation has been demonstrated to be mediated largely by the ubiquitin-proteasome pathway. We examined whether nascent apoB polypeptides or full-length apoB is selectively retrotranslocated from the endoplasmic reticulum into the cytosol for degradation. Herein, we found that full-length apoB as well as partial-length apoB peptides are ubiquitinated in HepG2 cells, and ubiquitination is an exclusively cytosolic process. Calnexin, which binds specifically to glycoproteins, has been postulated to promote apoB folding and complete translocation; we found that ubiquitinated apoB is bound to calnexin, suggesting that ubiquitinated apoB is glycosylated. In addition to calnexin binding, we have other pieces of evidence that the full-length intracellular ubiquitinated apoB is glycosylated, because (i) it binds to concanavalin A, and (ii) glycan can be demonstrated in the full-length ubiquitinated apoB by a chemical detection method involving oxidation of adjacent hydroxyl groups in the glycan moiety. Because glycosylation occurs inside the endoplasmic reticulum, the full-length glycosylated apoB must have been retrotranslocated into the cytosol for ubiquitination and proteasome-mediated degradation. Next we synchronized translation in HepG2 cells by puromycin treatment. A pulse-chase experiment using [35S]methionine labeling of intracellular apoB in these synchronized cells demonstrated that nascent partial-length apoB peptides are also ubiquitinated cotranslationally. We conclude that the ubiquitin proteasome-mediated degradation of apoB targets both nascent peptides cotranslationally before translocation as well as full-length apoB after its translocation into the endoplasmic reticulum.
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211
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Liao W, Chiu KY, Han S, Li F, Qiu J, Chow SP. Preliminary observation on the correlation between nm23 expression and Ki-67 antigen with early metastasis of human osteosarcoma. Chin Med J (Engl) 1998; 111:813-7. [PMID: 11155673] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023] Open
Abstract
OBJECTIVES To detect the nm23 expression in osteosarcoma, analyze the correlation between nm23 expression and early metastasis and to study the relation between nm23 expression with tumor differentiation and cell proliferation, as defined by Ki-67 labeling. METHODS nm23 oncoprotein expression was measured by immunohistochemical staining using formalin fixed, paraffin embedded sections of 39 surgically resected osteosarcomas and was compared with Ki-67 expression, histological findings and early metastasis. In each sample, the grading of immunoreactivity was recorded as 0, 1+, 2+ according to the percentage of nm23 and Ki-67 labeling cells respectively. RESULTS The cases with more than 25% positive immunoreactivity of nm23 protein were detected in 48.7% of the total cases. There was no statistical difference between nm23 expression and early metastasis, but the cases with nm23 expression appeared to have a trend to get early metastasis. nm23 expression was significantly correlated with Ki-67 expression, which was associated with differentiation of the tumor cells. CONCLUSION The role of nm23 as a tumor metastasis suppressor in osteosarcoma is less prominent. Both nm23 and Ki-67 may help predict the possibility of early metastasis in human osteosarcomas.
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Liao W, Chiu K, Mabuni C, Soliman M. Analysis of sennosides A and B from Dieter's tea by HPLC-diode array spectrophotometry and negative ion electrospray mass spectrometry. BULLETIN OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 1998; 61:317-324. [PMID: 9724354 DOI: 10.1007/s001289900765] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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213
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Zhou Y, Liao W, Mei F. [Histological and electrophysiologic changes of injury of dorsal root ganglia]. ZHONGGUO XIU FU CHONG JIAN WAI KE ZA ZHI = ZHONGGUO XIUFU CHONGJIAN WAIKE ZAZHI = CHINESE JOURNAL OF REPARATIVE AND RECONSTRUCTIVE SURGERY 1998; 12:145-9. [PMID: 10437052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Abstract
Injury of dorsal root ganglia (DRG) may cause sensory and motor dysfunction. In order to investigate the changes of somato-sensory evoked potential (SEP) and histological characteristics of DRG in different causes and different periods of injury, fifty-two rabbits were chosed to build the models. The rabbits were divided into 4 groups: Control group (n = 4); mechanical compressing group (n = 16); inflammatory injury group (n = 16); and treatment group (2% lidocaine with hydroprednisone was administered locally, n = 16). After one to eight weeks, SEP was determined and samples of DRG were obtained to observe the histological and ultrastructural changes every week. The result showed that the gap junction of microvascular endothelium in DRG had been destroyed by the mechanical compression was the major cause of the vessel permeability increasing. The increasing of endothelial pinocytic vesicles transportation and widening of endothelial gap junction were the main causes of inflammatory irritation of DRG. The local infiltration with 2% lidocaine and hydroprednisone could obviously ameliorate inflammatory injury in DRG.
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214
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Guan C, Liu Y, Shao Y, Cui T, Liao W, Ewel A, Whitaker R, Paulus H. Characterization and functional analysis of the cis-autoproteolysis active center of glycosylasparaginase. J Biol Chem 1998; 273:9695-702. [PMID: 9545304 DOI: 10.1074/jbc.273.16.9695] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Glycosylasparaginase is an N-terminal nucleophile hydrolase and is activated by intramolecular autoproteolytic processing. This cis-autoproteolysis possesses unique kinetics characterized by a reversible N-O acyl rearrangement step in the processing. Arg-180 and Asp-183, involved in binding of the substrate in the mature enzyme, are also involved in binding of free amino acids in the partially formed substrate pocket on certain mutant precursors. This binding site is sequestered in the wild-type precursor. Binding of free amino acids on mutant precursors can either inhibit or accelerate their processing, depending on the individual mutants and amino acids. The polypeptide sequence at the processing site, which is highly conserved, adopts a special conformation. Asp-151 is essential for maintaining this conformation, possibly by anchoring its side chain into the partially formed substrate pocket through interaction with Arg-180. The reactive nucleophile Thr-152 is activated not only by deprotonation by His-150 but also by interaction with Thr-170, suggesting a His-Thr-Thr active triad for the autoproteolysis.
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215
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Snyder M, Pearson V, Hanscom J, Hoyman K, Hagans E, Lee H, Liao W, Ryden M. Barriers to progress in urinary incontinence: achieving quality assessments. Geriatr Nurs 1998; 19:77-80. [PMID: 9611504 DOI: 10.1016/s0197-4572(98)90041-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Urinary incontinence is a major care problem in nursing homes. Despite legislation aimed at decreasing its incidence, minimal progress has been made to achieve this goal. Obtaining an accurate assessment about the level and pattern of incontinence will assist caregivers in developing plans to reduce it. This article identifies barriers the authors have encountered in obtaining accurate records in a research project and strategies implemented to overcome these barriers.
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Abstract
We report the construction of a genomic library and isolation of repetitive DNA probes from Cr. neoformans that are species- and variety-specific. The inserts of the genomic library were in a range of 0.3-1.8 kb, which were in normal distribution in length. Among 592 clones of the genomic library, there were 400(67.6%) clones inserted repetitive DNA sequence and 192(32.4%) inserted single copy DNA sequence of the Cr. neoformans genome. From the library, three specific probes were identified. Clone pCNIIA6 was serotype A-specific, pCNIIB5 species-specific, and pCNIIIG1 variety-specific (var. neoformans). On the basis of the high specificity and sensitivity of the signals observed by hybridization, we suggest that these probes provide a means for both biotyping and early diagnosis of Cr. neoformans.
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Abstract
The aim was to evaluate efficacy and tolerance of a short-schedule treatment regimen using a small dose of itraconazole in pulse intermittently. The open study evaluated the pulse therapy consisting of monthly 1-week cycles of oral itraconazole 200 mg daily for 2-3 consecutive months in 42 patients with onychomycosis. After active therapy, patients were evaluated for a maximum period of 1 year. Twelve of 42 patients were considered as being clinically cured, 17 were markedly improved, 11 were improved and two were failures. A mycological examination at the final visit was performed on all patients. Thirty-five were negative and seven were positive. This short treatment was well tolerated, with no adverse reactions, and may offer a new option for treatment of onychomycosis.
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218
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Zhao G, Liao W, Cai J. [Recovery of motor function of spinal cord with embryonic spinal cord graft in adult rat]. ZHONGGUO XIU FU CHONG JIAN WAI KE ZA ZHI = ZHONGGUO XIUFU CHONGJIAN WAIKE ZAZHI = CHINESE JOURNAL OF REPARATIVE AND RECONSTRUCTIVE SURGERY 1997; 11:332-4. [PMID: 9867998] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
The capacity of embryonic spinal cord tissue in the repair of injured structure of spinal cord has been noted for years. In order to investigate the embryonic spinal cord graft in the repair of motor function of injured spinal cord, the embryonic spinal cord tissue was transplanted to the hemisection cavity in spinal cord in adult rat. One hundred adult Wistar Rats were used to simulate the hemisectional injury of spinal cord by drilling 2-3 mm cavity in lumbar enlargement. Sixty rats were treated with rat embryonic spinal cord tissue grafting while the other forty were chosen as control. The outcome was evaluated according the combined behavioural score (CBS) and motor evoked potential (MEP) in the 1, 2, 4 and 12 weeks. The grafting group was superior to the control as assessed by CBS (P < 0.05), especially within 4 weeks. (P < 0.01). The restoration of the latent peak of early wave(P1, N1) was better in the grafting group, too. This suggested that embryonic spinal cord graft could improve the recovery of motor function of injured spinal cord in adult rat. The effect of the embryonic spinal cord tissue graft might be concerned with its secretion of several kinds of neurotrophic factors, nerve growth factor, nerve transmitted factor, or adjustment of hormone.
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219
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Yang F, Liao W. [Approximate entropy: a complexity measure suitable for short data]. ZHONGGUO YI LIAO QI XIE ZA ZHI = CHINESE JOURNAL OF MEDICAL INSTRUMENTATION 1997; 21:283-286. [PMID: 11189279] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The definition, algorithm and application of approximate entropy are introduced. A discussion is made on the reason of it merits.
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220
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Wang P, Liu J, Liao W, Xu S, Luo D, Sun B. [Mutual regulation of proliferation between pulmonary artery endothelial cells and pulmonary smooth muscle cells in vitro]. ZHONGGUO YING YONG SHENG LI XUE ZA ZHI = ZHONGGUO YINGYONG SHENGLIXUE ZAZHI = CHINESE JOURNAL OF APPLIED PHYSIOLOGY 1997; 13:209-12. [PMID: 10074261] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Abstract
Vascular endothelial cell are closely related to vascular smooth muscle cells in structure and function. The interactions between them may play important roles in the modulation of function and structure of vascular wall. In the present study, the mitogenic regulations between cultured new bovine pulmonary arterial endothelial cell (PAEC) and pulmonary arterial smooth muscle (PASM) were investigated. When PAECs and PASMs were mixcultured, 3H-TdR incorporation into the mixed cells decreased significantly (P < 0.001 vs control). When PAECs and PASMs were cultured in conditioned medium from PASMs and PAECs respectively or they were cocultured, the proliferation of PAECs was inhibited while that of PASM was stimulated significantly (P < 0.05 vs control). It was also found that the concentration of cAMP increased but cGMP decreased in cocultured PASMs (P < 0.01 vs control), while the concentration of both cAMP and cGMP decreased significantly in cocultured PAECs (P < 0.01 vs control). These findings suggest that PAECs and PASMs may regulate their proliferation each other through the second messenger system.
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Liao W, Angelin B, Rudling M. Lipoprotein metabolism in the fat Zucker rat: reduced basal expression but normal regulation of hepatic low density lipoprotein receptors. Endocrinology 1997; 138:3276-82. [PMID: 9231778 DOI: 10.1210/endo.138.8.5337] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Hyperlipoproteinemia is one of the phenotypic characteristics of the fat Zucker rat that carries a mutation in the leptin receptor gene. In the present study, we studied the regulation of hepatic low density lipoprotein (LDL) receptor expression in lean and fat Zucker rats. Compared with lean rats, the fat ones had a pronounced (approximately 60%) reduction in hepatic LDL receptor expression, whereas the levels of receptor messenger RNA (mRNA) were not reduced. Fat rats had increased levels of very low density lipoproteins and high density lipoproteins, but their plasma apo B100 within LDL was reduced. Challenge with 2% dietary cholesterol for 8 days suppressed hepatic LDL receptor expression in lean animals to similar levels as seen in fat ones, whereas the reduction in mRNA levels was much less pronounced. Treatment with ethynylestradiol (5 mg/kg BW per day) for 4 days strongly stimulated hepatic LDL receptor expression in both lean and fat rats; this treatment also increased LDL receptor mRNA levels, but to a lesser extent. In conclusion, the basal expression of hepatic LDL receptors is reduced in fat Zucker rats, but the capacity for the regulation of the receptors remains intact.
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Yang F, Liao W. Modeling and decomposition of HRV signals with wavelet transforms. IEEE ENGINEERING IN MEDICINE AND BIOLOGY MAGAZINE : THE QUARTERLY MAGAZINE OF THE ENGINEERING IN MEDICINE & BIOLOGY SOCIETY 1997; 16:17-22. [PMID: 9241515 DOI: 10.1109/51.603643] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
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223
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Zhao M, Zhang Y, Liu L, Liu Y, Liao W. Somatosensory- and motor-evoked potentials in a rabbit model of spinal cord ischemia and reperfusion injury. Spine (Phila Pa 1976) 1997; 22:1013-7. [PMID: 9152452 DOI: 10.1097/00007632-199705010-00014] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
STUDY DESIGN Occlusion of the infrarenal abdominal aorta was applied to adult rabbits, which induced spinal cord ischemia, followed by disocclusion and reperfusion. Cortical somatosensory- and motor-evoked potentials were monitored continuously up to 24 hours and correlated to hind limb motor and sensory status. OBJECTIVES To investigate cortical somatosensory-, and motor-evoked potentials in the rabbit model of spinal cord ischemia and reperfusion injury, especially their changes during reperfusion and their relationship to hind limb motor and sensory function. SUMMARY OF BACKGROUND DATA Various evoked potentials have been widely studied in neurologic prognosis of spinal cord ischemia. Little information is available from previous studies to correlate cortical somatosensory- and motor-evoked potentials with secondary paraplegia occurring during the reperfusion phase. METHODS Acute spinal cord ischemia was induced in eight anesthetized rabbits by occlusion of the infrarenal abdominal aorta just beneath left renal artery for 40 minutes. Cortical somatosensory-evoked potentials, elicited by stimulating the posterior tibial nerve and recorded at the skull surface corresponding to sensory projection area, and motor-evoked potentials, elicited by stimulating the skull surface corresponding to the motor projection area and recorded at L4 lamina of the vertebral arch, were monitored immediately before and at different time points during ischemia and reperfusion up to 24 hours after disocclusion. Hind limb motor and sensory functions were evaluated and correlated with cortical somatosensory- and evoked-potentials. RESULTS Cortical somatosensory-evoked potentials disappeared gradually after the start of occlusion and reappeared during reperfusion. Motor-evoked potentials did not change significantly during occlusion, but deteriorated after disocclusion; they correlated well with hind limb motor and sensory status. CONCLUSIONS Reperfusion injuries to the spinal cord might occur in the rabbit model after disocclusion. Cortical somatosensory-evoked potentials seemed to be a very sensitive index for spinal cord ischemia, whereas motor-evoked potentials correlated well with the course of reperfusion injuries after disocclusion and reflected long-term follow-up hind limb motor function better than cortical somatosensory-evoked potentials.
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Liao W, Rudling M, Angelin B. Novel effects of histamine on lipoprotein metabolism: suppression of hepatic low density lipoprotein receptor expression and reduction of plasma high density lipoprotein cholesterol in the rat. Endocrinology 1997; 138:1863-70. [PMID: 9112380 DOI: 10.1210/endo.138.5.5115] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Histamine has been shown to be involved in atherosclerosis and coronary heart disease. Little information is available regarding the effects of histamine on lipoprotein metabolism. In the current study, we investigated the effects of histamine on the expression of hepatic low density lipoprotein (LDL) receptors and on plasma lipoproteins in the rat. Injection of compound 48/80 (C48/80, a histamine releaser) or histamine reduced hepatic LDL receptor expression, but not LDL receptor messenger RNA levels. Oral administration of polymyxin B (an antiendotoxin antibiotic and a histamine releaser) before the injection of C48/80 or histamine did not attenuate their effects. Polymyxin B itself had effects similar to those of C48/80 and histamine on LDL receptors. These results suggest that the effects of histamine are not mediated by the induction of gut-derived endotoxemia. Histamine H2 agonists (dimaprit and impromidine), but not H1 agonists (2-methylhistamine and 2-thiazolylethylamine), also reduced hepatic LDL receptor expression. The suppressive effect of C48/80 on hepatic LDL receptor expression was not attenuated by either the H1 antagonist (chlorpheniramine) or the H2 antagonist (cimetidine). Administration of C48/80 also reduced plasma high density lipoprotein (HDL) cholesterol. The H1 antagonist (chlorpheniramine), but not the H2 antagonist (cimetidine), almost completely reversed the effect of C48/80 on plasma HDL cholesterol. In conclusion, histamine suppresses hepatic LDL receptor expression via a non-H1 receptor-mediated pathway, and histamine reduces plasma HDL cholesterol via an H1 receptor-mediated pathway.
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Tafti M, Nishino S, Liao W, Dement WC, Mignot E. Mesopontine organization of cholinergic and catecholaminergic cell groups in the normal and narcoleptic dog. J Comp Neurol 1997; 379:185-97. [PMID: 9050784 DOI: 10.1002/(sici)1096-9861(19970310)379:2<185::aid-cne2>3.0.co;2-#] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Canine narcolepsy is a unique experimental model of a human sleep disorder characterized by excessive daytime sleepiness and cataplexy. There is a consensus recognition of an imbalance between cholinergic and catecholaminergic systems in narcolepsy although the underlying mechanisms remain poorly understood. Possible substrates could be an abnormal organization, numbers and/or ratio of cholinergic to catecholaminergic cells in the brain of narcoleptic dogs. Therefore, we sought to characterize the corresponding neuronal populations in normal and narcoleptic dogs (Doberman Pinscher) by using choline acetyltransferase (ChAT), nicotinamide adenosine dinucleotide phosphate (NADPH)-diaphorase, tyrosine hydroxylase (TH), and dopamine beta-hydroxylase (DBH). Cholinergic cell groups were found in an area extending from the central to the gigantocellular tegmental field and the periventricular gray corresponding to the pedunculopontine tegmental nucleus (PPT), the laterodorsal tegmental nucleus (LDT), and the parabrachial nucleus. An almost perfect co-localization of ChAT and NADPH-diaphorase was also observed. Catecholaminergic cell groups detected included the ventral tegmental area, the substantia nigra, and the locus coeruleus nucleus (LC). The anatomical distribution of catecholaminergic neurons was unusual in the dog in two important aspects: i) TH- and/or DBH-immunoreactive neurons of the LC were found almost exclusively in the reticular formation and not within the periventricular gray, ii) very few, if any TH-positive neurons were found in the central gray and dorsal raphe. Quantitative analysis did not reveal any significant differences in the organization and the number of cells identified in the LDT, PPT, and LC of normal and narcoleptic dogs. Moreover, the cholinergic to catecholaminergic ratio was found identical in the two groups. In conclusion, the present results do not support the hypothesis that the neurochemical imbalance in narcolepsy could result from abnormal organization, numbers, or ratio of the corresponding neuronal populations.
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