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Biomedical subjects

H Liu

Publications and source records attributed to H Liu.

At least 757 records · Page 42Linked to original sources
PubMed1998

[An endometrium morphometry study on ovariectomized rats subjected to nilestriol and estradiol replalcement therapies].

This study was designed to evaluate the effect of estrogen on rat endometrium and compare the results of Nilestriol and Estradiol replacement therapies for preventing osteoporosis in ovariectomized rats. Forty 4-month old SD female rats were randomly divided into four groups, namely sham operation, bilateral ovariectomy, ovariectomy plus supplementary ethinyl estradiol (0.2 microgram/100 g B. W. qd x 5), and ovariectomy plus supplementary Nilestriol (0.15 mg/100 g B. W. once a week). Computerized image analyzer was used to evaluate the endomitrial pathological changes 10 weeks later. The results showed an atrophied endometrium in ovariectomized group, a slightly proliferative endometrium in Nilestriol treated group, and a markedly proliferative endometrium with local atypical hyperplasia in estradiol treated group. The difference between group 3 and group 4 in morphometry was significant (P < 0.5). These suggest the relative safety of Nilestriol replacement therapy for preventing menopausal osteoporosis.

Animals↗
PubMed1998

[Cloning and identification of cDNA fragments related to human esophageal cancer].

OBJECTIVE: To search new genes related to human esophageal cancer (EC) for revealing carcinogenesis mechanism and genetic susceptibility of EC. METHODS: Three normal esophageal epithelia (including 1 tumor-adjacent tissue) and two primary squamous cell carcinomas collected from high incidence family in Lin-xian county were studied using technique of mRNA differential display. The differential fragments were sequenced and identified by RT-PCR assay. RESULTS: (1) Eighteen differential fragments were isolated and identified, 13 of which were expressed in normal esophageal epithelia but not in EC(assigned as normal esophageal gene, NEG), while 5 were expressed in EC but not in normal esophageal epithelia(assigned as mutated esophageal gene, MEG). (2) Four NEG fragments were not homologous to the known sequences in the public database of GenBank (of NLM in USA). These 4 fragments were assigned as esophageal cancer related gene (ECRG) 1 to 4. (3)The remaining 14 fragments were homologues to 12 known genes or gene fragment. Their role in EC remains unclear. (4) Using RT-PCR technique, the expression of ECRG between normal epithelia and EC was significantly different. (5) All 4 ECRG genes were expressed in cDNA libraries derived from normal fetal brain, adult brain, liver, kidney, testis, bone marrow and skeletal muscle. (6) In the 20 cancerous and tumor-adjacent tissues obtained from the liver, lung, breast, colo-rectum and endometria, ECRG1 and ECRG2 was not detected by RT-PCR, while ECRG3 was highly expressed. For the ECRG4 the expression was much stronger in tumor-adjacent tissues than in cancerous tissues. CONCLUSION: ECRG 1 and ECRG2 may contribute to the causation and progression of the EC in Lin-xian, and may be candidates of tumor suppressor genes.

Carcinoma, Squamous Cell↗
PubMed1998

[A primary study of transcranial magnetic stimulation (TMS)-induced muscle silent period(SP) in stroke patients with mild hemiparesis].

OBJECTIVE: To investigate the changes of muscle silent period (SP) induced by transcranial magnetic stimulation (TMS) and its value in the evaluation of motor function in patient with stroke. METHODS: 25 normals and 23 stroke patients with mild hemiparesis were involved in this study. A MES-10 magnetic stimulator and a 9 cm round coil were used to stimulate the brain at an intensity 50% above threshold for MEP with the subjects making sustained moderate contraction of the contralateral FDI. SP duration and interside ratio were measured and calculated and then compared between the two groups. RESULTS: Normal values of SP duration and interside ratio were 145 +/- 37 ms and 1.01 +/- 0.15 respectively. The SP duration on the paralytic side in stroke patients was 423 +/- 314 ms, significantly prolonged in comparison with that on the normal side (154 +/- 54 ms, P < 0.05) and that of normal value (P < 0.01). The interside SP ratio (paralytic/normal side) in stroke patients was 2.8 +/- 1.9, also significantly higher than the normal value (P < 0.01). CONCLUSION: SP might be a sensitive and valuable neurophysiological parameter in evaluation of the motor function of patients with central motor dysfunction.

Adult↗
PubMed1998

[The clinical study of immune factors relative to Menière's disease].

It was investigated that the clinical unspecialized immunological factors and special immune reaction against to inner ear antigens relate with the cause of Meniere's disease. Every of the relative immune tests and special humoral and cellular immune reaction tests were proceeded in the breaking out and intermittent period of Meniere's disease patients, and the normal controls. The levels of IgG and C3 in serum and unspecialized lymphocyte blastogenesis increased, and positive of circular immune compound and antibody against cellular nucleus, and special humoral and cellular immune reaction against inner ear antigens during the breaking out period of the patients. The element of inner ear autoimmune could play an important role in the pathogenical mechanism of some patients with Meniere's disease.

Adolescent↗
PubMed1998

[Induction of apoptosis of CD34+ cells by serum from two patients with severe aplastic anemia].

OBJECTIVE: To explore the relationship between the hematopoietic inhibitor and apoptosis of CD34+ cells in patients with severe aplastic anemia (SAA). METHODS: The inhibiting activity to the growth of both BFU-E and CFU-GM was analysed by in vitro methylcellulose culture and CD34+ cell apoptosis was assayed with a kit of programmed cell death assay and flow cytometry. RESULTS: Sera from two SAA patients suppressed the growth of normal hematopoietic progenitor cells and induced CD34+ cell apoptosis. Serum immunoglobulin fraction assay showed that the inhibiting activity was in the IgG fraction which bound specifically to CD34+ cells. CONCLUSION: There was an inhibitive IgG fraction, which induced CD34+ cell apoptosis, in the serum of SAA patients and CD34+ cell apoptosis might be a part of the pathogenesis of SAA.

Adolescent↗
PubMed1998

[Multivariate analysis of clinicopathological and immunohistochemical factors in colorectal carcinomas].

OBJECTIVE: To determine the effect of clinicopathological and immunohistochemical factor on the prognosis of colorectal carcinoma. METHODS: The Cox model was used in a series of 68 colorectal carcinomas to study ten prognostic factors. These factors included tumor growth, stromal lymphocyte infiltration and fibrous tissue proliferation, degree of differentiation, Dukes stage, p53 protein, c-erbB-2 protein, P21 protein, PCNA proliferation index and EGFR. RESULTS: Monovariate analysis showed that tumor growth, stromal lymphocyte response, Dukes stage, p53, c-erbB-2 protein and PCNA index influenced prognosis significantly; multivariate analysis revealed 4 significant prognostic factors; P21, c-erbB-2 protein, Dukes stage and PCNA index. The relative risk (RR) for mortality was high in patients having P21 and c-erbB-2 co-expression. The RR of P21 and c-erbB-2 protein positive patients in Dukes A stage was higher than that of P21 and c-erbB-2 protein negative patients in Dukes B stage. CONCLUSIONS: P21, c-erbB-2 protein, PCNA index and Dukes stage were independent predictors of survival. The prognosis of patients with P21 and c-erbB-2 protein co-expression was worse than in patients without this co-expression.

Colorectal Neoplasms↗
PubMed1998

[Detection of the p53 protein accumulation and p53 gene mutation in squamous cell carcinoma of the lung].

OBJECTIVE: To investigate the effects of p53 protein accumulation and p53 gene mutation in the pathogenesis of squamous cell carcinoma of lung. METHODS: Immunohistochemistry and PCR-SSCP techniques were used to detect p53 protein accumulation and p53 gene mutation. RESULTS: p53 protein accumulations was found in 52.5% (63/120) of the samples. p53 gene mutation was detected in 56.7% (68/120) of the same specimens by PCR-SSCP. In 24 cases (35.3%, 24/68), the mutations was locating on exon 5, 11 cases (16.2%, 11/68) on exon 6, 18 cases (26.5%, 18/68) on exon 7 and 15 cases (22.1%, 15/68) on exon 8 respectively. The rate of p53 gene mutation/overexpression was 60%. p53 gene mutation/overexpression rate of moderately (63.6%, 28/44) or poorly (63.5%, 40/63) differentiated pulmonary squamous cell carcinoma was significantly higher than that of the well differentiated carcinoma (30.8%, 4/13). In comparing with non-lymph node metastasis group (43.1%, 28/65), p53 gene mutation/overexpression rate in metastasis group (80%, 44/55) was significantly higher. p53 gene mutation/overexpression rate of pulmonary squamous cell carcinoma in advanced stage (76.3%, 45/59) was significantly higher than that in the early stage (44.3%, 27/61). p53 gene mutation/overexpression rate in heavy smoking group (72.4%, 55/76) was significantly higher than that in non-smoking group (38.6%, 17/44). No statistically significant correlation was found between p53 gene mutation/overexpression and sex, age, tumor location or invasion of the surrounding tissue. CONCLUSIONS: p53 gene mutation/overexpression may play an important role in the pathogenesis of squamous cell carcinoma of lung and can be considered as a predicting marker of prognosis.

Adult↗
PubMed1998

[Cochlear and retrocochlear deafness induced by immunity with different inner ear tissue antigens].

OBJECTIVES: To inquire into whether the different inner ear tissue antigens could cause different kind of hearing loss, and to find out the disorder positions of auditory system. METHODS: The basilar membrane (BM), spiral ligament (SL), and spiral ganglion (SG) of guinea pigs were removed for making antigens, respectively. Then, we used these antigens to immune guinea pigs. The special humour and cellular immune reaction, hearing function, and inner ear histopathological changes were observed. RESULTS: In BM-antigen and SL-antigen immune group, the various degrees of cochlear microphonic potential disturbance, recruitment, and immune pathological inflammation in cochlear duct and stria vascularis were found. In SG-antigen immune group, auditory nerve compound action potential changes were prominent, and the inner ear pathological damage mainly existed in cochlear axis vessels or surround areas, and SG. CONCLUSIONS: It was confirmed that the inner ear antigens come from different part of auditory system, which could cause cochlear or retrocochlear autoimmune disease.

Animals↗
PubMed1998

Experimental study on liver microcirculation disturbance following transplantation and the protective effect of prostaglandin E1 in the rat.

OBJECTIVE: To determine the effect of PGE1 on liver microcirculation disturbance following orthotopic liver transplantation in rats. METHODS: Forty male adult Wistar rats were divided randomly into 3 groups. Eight transplantations were established in both the experimental and control group, while in the sham group, the liver was dissected like in the experimental group, but no resection was performed. In the experimental group, PGE1(0.5 microgram/kg.min-1) was injected intravenously into the donor before the operation, and added (1 mg/L) to the flush and preservation fluid, while PGE1 was replaced by normal saline in the control group. Confocal laser scan microscopy, biochemical test, and optical and electronic microscopy were used. RESULTS: In the control group the reperfusion state was poor, leukocyte infiltration appeared in the center of lobule, and transaminase rose after transplantation. In the experimental group distinctive improvement was seen as compared with the control group (P < 0.05). Histological findings showed progressive degeneration and necrosis following transplantation in the control group, while in the experimental group the histological changes were improved to some degree by the use of PGE1. CONCLUSIONS: In liver transplantation, ischemic reperfusion damage may lead to hepatic microcirculation disturbance, which is the major cause of graft failure. Infusing PGE1 into the donor intravenously before ischemia and adding PGE1 to the cold storage fluid could improve hepatic microcirculation, and thus reducing ischemic reperfusion damage in liver transplantation.

Alprostadil↗
PubMed1998

Pharmacokinetics of intravenous arsenic trioxide in the treatment of acute promyelocytic leukemia.

OBJECTIVE: To study the pharmacokinetics and metabolism of arsenic trioixide (As2O3) and its main side effects. METHOD: As2O3 was administered intravenously at the dose of 10 mg per day for the treatment of 8 relapsed acute promyelocytic leukemia (APL) patients. The arsenic content was measured by Gas-phase chromatography. RESULTS: The plasma maximal concentration (Cpmax) was 0.94 +/- 0.37 mg/L (x +/- s), time to peak concentration (Tp) was 4 hours, plasma distribution half-time (t1/2 alpha) and elimination half-time (t1/2 beta) were 0.89 +/- 0.29 hours and 12.13 +/- 3.31 hours, respectively. Apparent distribution volume (Vc) was 3.83 +/- 0.45 L, system clearance (CLs) was 1.43 +/- 0.17 L/h, and area under curve (AUC) was 7.25 +/- 0.97 mg.h/L. The continuous administration of As2O3 did not alter its pharmacokinetic behaviors. During As2O3 treatment, 24-hour arsenic content in urine accounted for 1%-8% of the daily dose (10 mg). When arsenic accumulation in hair and nail increased continuously, the peak concentration could be five to seven-fold higher than that of pre-treatment. Importantly, arsenic contents in both urine and hair or nail declined gradually after drug withdrawal. No bone marrow suppression or severe organ-impairment was found. CONCLUSION: As2O3 is a relatively safe and effective remedy in the treatment of patients with relapsed APL, in spite of certain degree of arsenic accumulation in some tissues.

Adolescent↗
PubMed1998

[Chiral HPLC determination of conversion and enantiomeric excess of enzyme catalyzed stereoselective esterification of racemic ibuprofen].

In the study of enzyme catalyzed kinetic resolution of racemates, it is imperative to assay how the optical yield varies with chemical conversion. In this paper, a method using one-time injection to determine enantiomeric excess and conversion of the stereoselective esterification of racemic ibuprofen with n-butanol catalyzed by lipase was developed with a commercially available HPLC CSP column Regis(S, S) Whelk-01. In the linear range of detector, all peak areas of products and substrates are proportional to their concentrations. Because the total mole concentration remains unchanged (equal to the initial value of ibuprofen) in the reaction process, the conversion could be calculated from the peak areas, provided the ratio of response factors was known. The calibration curves of two ibuprofen enantiomers with racemic ibuprofen as external standard were overlapped, indicating fiR = fiS. By investigating the variation of peak areas of products and substrates against conversion (determined by external standard), the ratio of peak area-concentration response factor of ibuprofen butyl ester to that of unreacted ibuprofen was determined to be 1 through linear regressions, from which the conversion could be directly determined by the self normalization of the peak areas. With a mobile phase of IPA/hexane/HAc/triethylamine (15/85/0.2/0.05, V/V, flow rate 0.4 mL/min), the resolution of ibuprofen enantiomers was sufficient for precise enantiomeric purity determination.

Catalysis↗
PubMed1998

[Study on the analysis of zinc 5-aminosalicylate and related compounds by high performance liquid chromatography].

In this paper, the separation and determination conditions of zinc 5-aminosalicylate (ZASA) and related compounds by high performance liquid chromatography(HPLC) have been studied systematically. The baseline separation was achieved at 20 degrees C on a CLC-ODS column(150 mm x 6.0 mm i.d., 10 microns) within 10 minutes by using 1% (V/V) HAc-MeOH(4:6) as mobile phase at a flow-rate of 1 mL/min. The RSDs of rention time within day and between days were less than 2% and 5% respectively. The injection volume was 20 microL, and relationships between the peak area with 280 nm detection and the analyte concentration were linear within certain ranges. This method was used for determination of ZASA, impurities and thermal decomposition compounds. The results showed that the impurities in the crude ZASA were 5-aminosalicylic acid and salicylic acid. The thermal decomposition compounds in acid medium were 5-aminosalicylic acid, 5-aminophenol and 5-benzeneazosalicylic acid.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed1998

[Effects of traditional Chinese medicine on salivary glands in the patients with head and neck cancer during radiotherapy].

OBJECTIVE: To observe the effect of Chinese herbal medicine on the salivary glands of patients with head and neck cancer during radiotherapy (RT). METHODS: Fifty cases with head and neck cancer were randomly divided into observation group treated with RT plus Chinese herbal medicine and control group treated with RT alone. The level of mouth dryness, the flow and secretion speed of salivary amylase were measured before and during the RT. RESULTS: The severity of mouth dryness increased and the flow and secretion speed of salivary amylase declined during RT. The mouth dryness curve of patients in Chinese medicine group was significantly more flattened than that of the control group after RT. The flow and the secretion speed of salivary amylase of the observation group were significantly higher than those of the control group at 20 Gy, 40 Gy and 60 Gy. CONCLUSION: Chinese herbal medicine used in this study was effective to relieve the severity of mouth dryness and to protect the salivary glands of patients with head and neck cancer during RT.

Adult↗
PubMed1998

[Plantlet strengthening medium for Dendrobium candidum Wall. et Linde. of clonal propagation in vitro].

OBJECTIVE: To find a suitable medium for plantlet production of Dendrobium candidum in the period of strengthening plantlet. METHOD: The basic medium, natural aqueous extracts, density of banana aqueous extract and of plant hormones were tested. RESULTS AND CONCLUSION: The B5 or 1/2MS, added with 10% of banana aqueous extract and 2 mg/L NAA can be used as the best plantlet strengthening medium for Dendrobium candidum.

Culture Media↗
PubMed1998

[Preliminary studies on chemical constituents and pharmacological action of Eclipta prostrata L].

OBJECTIVE: To study the pharmacologically active components of Eclipta prostrata. METHOD: The components were extracted by alcohol and isolated by silica gel column and subjected to pharmacological screening. RESULT: Four compounds were isolated from E. prostrata, of which two were identified as stigmasterol and alpha-terthienyl. CONCLUSION: alpha-Terthienyl was isolated from the plant for the first time. The EtOAc part of alcoholic extraction exhibits significant hepatoprotective activity against carbon terachloride-induced liver injury in rats.

Alanine Transaminase↗
PubMed1998

[Chemical constituents of Tetrastigma hemsleyanum Diels. et Gilg].

OBJECTIVE: To investigate the chemical constituents of Tetrastigma hemsleyanum. METHOD: Compounds were separated by rechromatography on silica gel from the chloroform solubles of its ethanol extracts, and the structures were determined by spectral analysis and chemical evidence. RESULT: Three compounds were isolated and elucidated as 6'-O-benzoyldaucosterol, daucosterol and beta-sitosterol. CONCLUSION: All the three compounds were isolated from this plant for the first time, of which 6'-O-benzoyldaucosterol is a new natural product.

Drugs, Chinese Herbal↗
PubMed1998

[Effect of yuanhua on isolated uterine strips in unpregnant rats].

OBJECTIVE: To explore the mechanism on the effect of Yuanhua on the contractile activity of isolated uterine strips in rats under artificial oestrum. METHOD: Isolated strips were suspended in a tissue chamber in which Yuanhua was added with some antagonists of inhibitors or without. RESULT: Yuanhua could excite the uterine smooth muscle strips in a dose-dependent manner, but atropine, phentolamine, hexamethonium and diphenhydramine could not inhibit this exciting action. This exciting effect could be inhibited completely by verapamil and decreased by indomethacin(inhibitor of prostaglandin synthase). CONCLUSION: The exciting effect of Yuanhua on un-pregnant rats in vitro might be related to an action on the cell membrane Ca2+ channel as well as to a partial stimulation of synthesis and release of PG.

Animals↗