Biomedical subjects

J Liu

Publications and source records attributed to J Liu.

At least 523 records · Page 29Linked to original sources

PubMed2001

[The influence of transforming growth factor beta 1 (TGF beta 1) on fibroblast proliferation and collagen synthesis].

OBJECTIVE: To investigate the significance and the influence of transforming growth factor beta 1 (TGF beta 1) on fibroblast proliferation and collagen synthesis. METHODS: The fibroblasts derived from healthy human dermis and pathologic scar were harvested and cultured in vitro with TGF beta 1. The effects of TGF beta 1 on the proliferation and collagen synthesis of the fibroblasts were investigated during the early phase (24 h) of cell confluence by means of nonradioactive cellular proliferation detection, 3H thymidine and 3H proline incorporation and DNA quantification analysis. RESULTS: After the co-culture with TGF beta 1, the incorporation of 3H thymidine and 3H proline and the proliferation were enhanced significantly in the fibroblasts from pathologic scar (P < 0.01) but remained at normal level in those from healthy human dermis(P > 0.05). CONCLUSION: The cell proliferation and collagen synthesis of scar-derived fibroblasts could be positively modulated and controlled by TGF beta 1, which might be very important in the scar formation.

Cell Division↗

PubMed2001

[Study of triglyceride distribution aged 35 - 64, and their association with other cardiovascular disease risk factors in 11 provinces].

OBJECTIVE: Study of triglyceride distribution and their association with other major cardiovascular disease risk factors in 11 provinces. METHODS: Twenty-seven thousand and sixteen persons in 11 provinces, aged 35 - 64, were screened for cardiovascular disease risk factors. RESULTS: (1) Results of plasma triglyceride level distribution showed that there was significant difference among 11 province, the highest/lowest ratio was 2.3. (2) Plasma triglyceride level was higher in men than in women (P < 0.001). (3) The prevelance of hypertriglyceridemia was the most frequent type of the dislipidemia. (4) Multiple stepwise regression analysis showed that total cholesterol, high-density lipoprotein cholesterol, body mass index, blood pressure, blood glucose and physical activity, significantly and independently correlated with hypertriglyceridemia prevelance. (5) There existed aggregation of risk factors in hypertriglyceridemia. Seventy-one point zero percent of hypertriglyceridemia had at least one other risk factors in men and 74.4% in women, while it was 53.8% men and 52.2% women of those with non hypertriglyceridemia (P < 0.01). CONCLUSION: Our date indicated that fasting triglycerides were associated with more arteriosclerosis factors and could serve as a marker for several cardiovascular disease risk factors. More patients with hypertriglyceridemia combined with other situation of metabolic syndromes thus might have higher risks.

Adult↗

PubMed2001

[Cluster analysis study on the marshland of Schistosoma Japonicum using satellite TM image data in Peng Lake, Jiangxi province].

OBJECTIVE: To create a category land cover map of the marshland region of Schistosoma Japonicum using satellite TM data. METHODS: TM satellite images from Peng Lake of Jiangxi province were applied to the Cluster analysis. Then the resulting clusters were identified and reclassified by undertaking site visits. RESULTS: Eight land cover classes were generated, including Carexspp Zone that was the snail habitat place. CONCLUSION: Cluster analysis, which is a technique for the interpretation of remotely sensed imagery, could contribute to the study on the distribution of snail habitats and become a new tool for the epidemiological ecology study.

Animals↗

PubMed2001

[The effect of viper venom on the attachment, migration and proliferation of Tenon's capsular fibroblasts].

OBJECTIVES: To observe the effect of viper (Ahylysantipfarciasi) venom on attachment to collagen, migration and proliferation of rabbit Tenon's capsular fibroblast (TFs) in tissue culture. METHODS: Anti-adhesion experiment: The 3 -- 5 passage TFs suspended in DMEM medium were pre-incubated for 30 minutes in the presence of various concentrations of viper venom (0, 2.5 x 10(-4), 5.0 x 10(-4), 1.0 x 10(-3) and 5.0 x 10(-3) U/ml) at 37C, 5% CO(2), then inoculated in 24-well plate coated with rat-tail collagen. After incubation for 90 minutes, the floating cells were removed. The attached cells in each well were enumerated microscopically and determined by the value of absorption (A) of 3-(4, 5-dimethylthiazolzyl)-2, 5-diphenyl tetrazodium bromide (MTT). Anti-migration experiment: A denuded area was made when the 3rd passage of TFs was confluent into a monolayer. Cells were then exposed to viper venom (0 -- 5.0 x 10(-3) U/ml) at 37C, 5% CO(2), and the cells having migrated into the denuded area were enumerated every 6 hours. Anti-proliferative experiment: Two hours after the 3rd passage of TFs was incubated in the 24-well plate at 37C, 5% CO(2), they were exposed to different concentrations of viper venom drug (0 -- 5.0 x 10(-3) U/ml). Twenty-four and 48 hours later, the number of cells was determined by MTT method. RESULTS: Viper venom inhibited TFs from attaching to collagen in a dose-dependent manner and the ID(50) was 1.0 x 10(-3) U/ml. Only did 5.0 x 10(-3) U/ml of viper venom show significant difference from the control during 6 -- 48 hours. The difference of A value was not significant among all groups at 24 and 48 hr. CONCLUSIONS: In vitro, viper venom (> 1.0 x 10(-3) U/ml) can significantly inhibit the attachment of TFs to collagen, and 5.0 x 10(-3) U/ml can inhibit the migration, but can not affect their proliferation.

Animals↗

PubMed2001

[Experimental study and application of extracellular matrix of conjunctiva].

OBJECTIVE: To investigate the characteristics and application of extra-cellular matrix (ECM) of conjunctiva. METHODS: Pieces of conjunctival ECM were made, and then the conjunctival defect was repaired with that in an experimental group. Control group 1 received the heterogeneous conjunctiva, and in control group 2, the refrigerated ECM was used for transplantation. All of them were photographed and examined by light microscope, electron microscope (EM), immunohistochemical examination and lymphocyte toxicity test. RESULTS: There were blood vessels growing into the grafts on the 3rd day in the experimental group. The grafts became mildly congestive and similar to normal conjunctival ones in the 4(th) week. But in control group 1, the grafts became white and necrotic in the second week; the conjunctiva was congestive, cicatricial and hyperplastic in the 4(th) week. Under the light microscope, the epithelium covered the most part of the region with the graft in the 2nd week, covered completely in the 4(th) week, and its appearance was as an approximately normal conjunctival epithelium in the experimental group. But the epithelium became ulcerative and a lot of lymphocytes infiltrated in the 2nd week in control group 1. Under the EM, the line of demarcation between the covering region of the regenerative conjunctival epithelium and the naked ECM was quite clear in the 1st week in the experimental group. And the ultrastructure of regenerative conjunctival epithelium was basically the same as an normal one in the 8(th) week. Both before and after transplantation, the immunohistochemical examinations verified that ECM was type I and IV collagen. The lymphocyte toxicity test showed that no obvious humoral immunoreaction existed. CONCLUSION: Conjunctival ECM has the characteristics of tissue activity and low antigenicity. It is an ideal conjunctival succedaneum in the plastic surgery of conjunctiva.

Animals↗

PubMed2001

[A gene study on multidrug resistance of retinoblastoma].

OBJECTIVE: To investigate the expression of multidrug resistance gene (MDR1) and multidrug associated protein (MRP) gene in the retinoblastoma (Rb) cell line HXO-RB(44), and study the mechanism of multidrug resistance (MDR) phenotype occurring in retinoblastoma. METHODS: Reverse transcriptase polymerase chain reaction (RT-PCR) was employed to detect the transcription of MDR1 and MRP gene in the HXO-RB(44) cell line, and immunohistochemical technique was used to detect their protein products P-glycoprotein and multidrug resistance associated protein (P190). RESULT: Both MDR1 and MRP genes were expressed in HXO-RB(44) cell line, as well as P-glycoprotein and P190 were over-expressed (96% - 97%) in this cell line. CONCLUSION: Over-expression of MDR1 and MRP genes is significantly involved in the mechanism of MDR phenotype in retinoblastoma.

Cell Line, Tumor↗

PubMed2001

[Detection of methylation status of p16 tumor suppressor gene in soft tissue leiomyosarcoma].

OBJECTIVE: To observe the methylation status of p16 tumor suppressor gene in human soft tissue leiomyosarcoma (LMS) and its relationship with p16 protein expression. METHODS: Methylation-specific PCR (MSP) assay was used to analyze the methylation status of 5' CpG island promoter/exon I region of p16 tumor suppressor gene in 38 LMS, 10 leiomyomas and 5 normal smooth muscle tissues. p16 expression in these tissues were examined by immunohistochemical assay. RESULTS: Hypermethylation of p16 was observed in 23.7% (9/38) of cases, of which 7 with negative pl6 staining and 2 with faint positive staining. In the cases without protein expression, hypermethylation rate of p16 was 50% (7/14). CONCLUSIONS: Epigenetic change due to 5' CpG methylation is the main cause of inactivation of p16 (INK4) gene which may be involved in tumor pathogenesis.

CpG Islands↗

PubMed2001

[The dynamic changes of serum TNFalpha level in scalded rats after the administration of rhGH during the early postburn stage].

OBJECTIVE: To examine the dynamic change of serum TNFalpha level in scalded rats after the administration of rhGH during the early postburn stage. METHODS: Forty-two male sanitary Sprague-Dawley rats were randomly divided into three groups, i.e. normal control (N), burn with early administration of rhGH (BA) and burn without rhGH (BN) groups. The rats were inflicted with 25% similar 30% TBSA deep partial thickness scalding on the back. rhGH in dose of 6 U/kg was administered subcutaneously via abdominal skin starting from the 1st postburn day (PBD). Rat serum TNFalpha levels were determined by ELISA in BA and BN groups at 3, 6 and 10 PBDs. RESULTS: The rat serum TNFalpha level in BA was lower than that in BN groups on 3 PBD. Whilst the TNFalpha levels in BA were much higher than those in BN groups on 6 and 10 PBDs. CONCLUSION: Administration of rhGH at early postburn stage might abate the early systemic postburn reaction.

Animals↗

PubMed2001

[Study on new techniques for genetic diagnosis of deletional alpha-thalassemia].

OBJECTIVE: To develop polymerase chain reaction (PCR) techniques for diagnosis of three commonest deletional alpha-thalassemia determinants in China: - -(SA), - alpha(3.7) and - alpha(4.2). METHOD: Three groups of primers were designed and used to amplify the respective type of the deletional alpha-thalassemia under an optimized PCR condition, followed by agarose gel electrophoresis and EB-stainning. RESULT: Homozygous and heterozygotes, as well as double heterozygous of the 3 commonest deletions were successfully detected and diagnosed by the developed techniques. The results were identical to that from Southern Blot analysis. Forty two cases of alpha-thalassemia were diagnosed by these techniques. CONCLUSION: The 3 PCR-based techniques established by our lab were accurate, simple, and well reproducible for gene diagnosis of the deletional alpha-thalassemia determinants.

DNA Primers↗

PubMed2001

[Expression of recombinant human Flt3 ligand in Escherichia coli and its purification and characterization].

OBJECTIVE: To establish a highly efficient expression system of recombinant human Flt3 ligand (rhFL) in E. coli and a suitable purification method of the expressed products. METHOD: Human FL encoding cDNA was introduced into pProEXHT plasmid to express a 6 x His-FL fusion protein in E. coli. The fusion protein expressed in inclusion body was isolated, solubilized and refolded, and then purified by chromatography on a metal-chelating affinity column (MCAC). Its activity was detected by stimulating the proliferation of CD(34)(+) cells. RESULT: The amount of rhFL expressed was about 15% of total bacterial proteins and the purity of rhFL was 90% after MCAC. The combination of rhFL, granulocyte colony-stimulating factor and erythropoietin could stimulate CD(34)(+) cells to a 400 fold expansion. CONCLUSION: The purified rhFL had a potent activity to stimulate hematopoietic stem cells to expanse in vitro.

Cell Proliferation↗

PubMed2001

[Influence of chemotherapy on hematopoietic microenvironment and effect of autologous bone marrow stromal cell infusion on the recovery of hematopoiesis after chemotherapy].

OBJECTIVE: To observe the influence of chemotherapy on hematopoietic progenitor cells (HPC) and hematopoietic microenvironment (HME). To observe whether intravenous infusion of autologous bone marrow stromal cells (ABMSC) expanded in vitro can improve the hematopoietic function. METHODS: Cultures of CFU-GM, BFU-E, CFU-E and stromal progenitor cells (CFU-F) from normal control and chemotherapeutic patients were performed. The stromal function was analyzed by the assessment of the area of flask surface covered by stromal cells (ASSC) and the time when stromal cells reach confluence (TC). The recovery of hematopoietic function in short term chemotherapy group and long term chemotherapy, with or without ABMSC infusion (1.1 - 8.7) x 10(8) post chemotherapy groups was observed. RESULTS: The yields of CFU-GM, BFU-E, CFU-E and CFU-F in long term chemotherapy group were significantly lower than that in normal group or in short term chemotherapy group. There was no significant difference among three groups in the ASSC and TC. In long term chemotherapy group, the yields of CFU-GM, CFU-E, BFU-E and CFU-F after chemotherapy with BMSC infusion were significantly higher than that without BMSC infusion. In long term chemotherapy group, the lowest value of white blood cell (WBC) and platelet after chemotherapy with BMSC infusion was significantly higher than that without BMSC infusion. The times for WBC and platelets recovered to normal were significantly shorter in BMSC group than in without BMSC. No adverse reaction was observed with ABMSC infusion. CONCLUSION: Long term chemotherapy results in severe impairment in HPC and mesenchymal progenitor cell (MPC), but has no obvious influence on the in vitro BMSC confluent layer formation. Intravenous infusion of expanded ABMSC can accelerate the recovery of hematopoiesis after chemotherapy.

Adolescent↗

PubMed2001

[Study on apoptosis of human gastric adenocarcinoma cell SGC-7901 induced by aining in vitro and the cell cycle].

OBJECTIVE: To study the inducing apoptosis effect of Aining on human gastric adenocarcinoma cell in vitro. METHODS: Agarose gel electrophoresis (AGE) and flow cytometry (FMC) techniques were adopted to study the inducing apoptosis effect of Ainging on the human gastric adenocarcinoma cell. RESULTS: The human gastric adenocarcinoma cell's DNA was digested into fragments which gave rise to a characteristic "DNA Ladder" on agarose gel electrophoresis, while the percentage of apoptotic cells was 43.5%. But the blank group had neither DNA ladder, nor apoptotic peak. Cell cycle analysis showed that the proliferation index was 33.7% after the human gastric adenocarcinoma cells treated with Aining, and there was no cell phase specialty. CONCLUSION: Aining can induce human gastric adenocarcinoma cell apoptosis in vitro.

Adenocarcinoma↗

PubMed2001

[Selection of optimal ultrasonic extraction process of Elaeagnus angustifolia L. by uniform design].

The influences of ultrasonic frequency, ultrasonic time and solvent content on the extraction rate of fat oil in Elaeagnus angustifolia L. were studied. The optimum extraction condition was obtained. The results showed that the ultrasonic extraction method of fat oil in Elaeagnus angustifolia L. could save time, improve extraction rate and need not be hot compared with traditional extraction method.

Elaeagnaceae↗

PubMed2001

Efficacy of omalizumab, an anti-immunoglobulin E antibody, in patients with allergic asthma at high risk of serious asthma-related morbidity and mortality.

AIM: Add-on therapy with omalizumab, an anti-immunoglobulin E antibody, is effective in improving disease control in patients with allergic asthma of varying severity. The aim of the present study was to determine the efficacy of omalizumab in a subgroup of patients at high risk of serious asthma-related morbidity and mortality. METHODS: A meta-analysis was performed of three randomised, double-blind, placebo-controlled studies (studies 1, 2 and 3) that enrolled 1412 patients with moderate or severe allergic asthma, all requiring daily treatment with inhaled corticosteroids (ICS). Omalizumab was administered subcutaneously every 2 or 4 weeks at a total 4-weekly dose of at least 0.016 mg/kg/IgE [IU/ml]. Each study consisted of a 16-week steroid-stable phase and a 12-16-week steroid-reduction phase, followed by a 24-week extension phase (studies 1 and 2 only). The primary outcome measure was the annualised rate of significant asthma exacerbation episodes (sAEEs) during the steroid-stable phase for the pooled subgroup of 254 high-risk patients (omalizumab, n = 135; placebo, n = 119). sAEEs were those requiring a doubling of baseline ICS dose (studies 1 and 2 only) or use of systemic steroids (all three studies). RESULTS: Overall, the number of patients with at least one sAEE during the steroid-stable phase was reduced from 35% (42/119) with placebo to 18% (24/135) with omalizumab. Mean sAEE rates were 1.56 and 0.69 per patient-year, respectively, a reduction of 56% with omalizumab (p = 0.007). Similar reductions in exacerbations in favour of omalizumab were observed for the whole study period and for all AEEs. In those with a history of hospitalisation in the last year, 6/49 (12%) on placebo vs. 2/44 (4.5%) on omalizumab were re-hospitalised during the study period. Patients treated with omalizumab also showed significantly greater improvements from baseline in PEFR (p = 0.026), overall AQoL (p = 0.042) and mean nocturnal (p = 0.007) and mean total (p = 0.011) asthma symptom scores compared with placebo. CONCLUSIONS: In patients at high risk of serious asthma-related morbidity and mortality, treatment with omalizumab offers the potential to halve the rate of asthma exacerbations and improve disease control.

Adolescent↗

PubMed2001

[Inositol 1,4,5-triphosphate receptors (IP(3)Rs) in myocardial nuclei involved in pressure overload-induced hypertrophy of rat heart].

In order to clarify the importance of nuclear IP(3)Rs in the development of myocardial hypertrophy, a hypertensive rat model was established by abdominal aortic constriction, and velocity and isopyknic gradient centrifugation was employed to fractionate the cardiac nuclei. The maximal number of binding sites (B(max)) and dissociation constant (Kd) of IP(3) to the nuclear envelopes were measured by [(3)H] IP(3) binding assay. The existence of IP(3)Rs on myocardial nuclear envelope was confirmed. [Ca(2+)] inhibited [(3)H] IP(3) binding to its receptors in cardiac nuclear envelopes in a concentration-dependent way. Phosphorylation by CaM and endogenous PKC decreased B(max) of nuclear IP(3) receptors. B(max) and Kd of nuclear IP(3)Rs were increased by 1.217 (P<0.01) and by 2.149-fold (P<0.01) respectively in hypertrophic myocardium as compared with those of the control. The above results suggest that IP(3)Rs exist in myocardial nuclei and are down regulated by CaM, PMA and free Ca(2+). The increase of the binding sites of IP(3)Rs in the nuclear envelopes and the decrease of their affinity might play importment roles in the development of overload induction of cardiac hypertrophy.

Animals↗

PubMed2001

[Responses of afferent unit of the caudal nerve of diabetic hyperalgesic rats to sympathetic efferent stimulation].

Responses of afferent unit to sympathetic stimulation (SS), intravenous injection of noradrenaline (NA) and phentolamine in the caudal nerve of diabetic rats were investigated. The results showed that the discharge frequencies of C and Adelta units with spontaneous discharges were increased in diabetic hyperalgesic rats after SS, and these spontaneous discharges were eliminated by adrenergic antagonist. The C (6/21) and Adelta (19/81) units with no spontaneous discharges of diabetic hyperalgesic rat turned from silent state into active state during SS; although SS did not elicit afferent discharges of the C mechanical receptive units (C-M), it elicited afferent discharges of a part of C mechano heat units (C-MH) and C polymodal units (C-Pol); afferent discharges of some of the Adelta mechanical receptive units (Adelta-M) and Adelta mechano heat units (Adelta-MH) were also elicited by SS. The latencies of the C and Adelta units responses upon SS were not equal, but no less than 5 s. SS elicited neither afferent discharges from Abeta mechanical receptive units of diabetic hyperalgesic rat, nor receptive units of all types in the control rat. The C(3/8) and Adelta (4/12) units of diabetic hyperalgesic rat were activated by intravenous injection of NA. The present data suggest that NA released from sympathetic nerve terminals excites C and Adelta units of diabetic hypesthesic rat, which may be a peripheral factor in hyperalgesia and paresthesia of diabetic rats.

Afferent Pathways↗

PubMed2001

[Prognostic significance of heat shock proteins 70 and p27 protein in patients with mucoepidermoid carcinoma].

OBJECTIVE: To study the expression of heat shock proteins 70 (HSP70) and p27 in mucoepidermoid carcinoma (MEC) in relation to biological behaviour and prognosis. METHODS: Immunohistochemical LSAB method was used to evaluate the expression of HSP70 and p27 in 44 MEC. 10 Pleomorphic adenomas (PAs) were used as controls. RESULTS: The expression of HSP70 was significantly higher in MEC than in PAs, while p27 expression was significantly lower in MEC than in PAs. There was a negative correlation between HSP70 and p27 expression. Compared with clinicopathologic features, the expression of HSP70 was related to histologic grade, clinical stage and tumor size, and p27 expression correlated negatively with histologic grade, clinical stage, tumor size and lymph node metastases. Multivariate analysis revealed that Hsp70 expression was a strong prognostic indicator of MEC. CONCLUSIONS: HSP70 should be considered an independent prognostic indicator of MEC and p27 might favour prognosis of MEC.

Adenoma, Pleomorphic↗

PubMed2001

[Establishment and biologic characterization of human hepatocellular carcinoma cell line HCC-9903].

OBJECTIVE: To establish a new hepatocellular carcinoma (HCC) cell line and provide a new and ideal experimental model. METHODS: The cell line designated as HCC-9903 was derived from a surgical specimen of HCC. After primary culture, its biologic characteristics were studied under light and electron microscope and by determination of doubling time and growth curve, culture in soft agar, flow cytometry(FCM), chromosome analysis, detection of AFP, HBV and telomerase, agglutination test of concanavalin (ConA) as well as inoculation in nude mice. RESULTS: The first passage was found on the 29th day. Morphological study demonstrated its malignant characteristics. Chromosome analysis revealed a chromosome number ranging from 49 to 135, with a model number of 52 to 67. Aberrant chromosomes 1 q(i) and t (6,11) were its chromosome markers. The cell line produced tumors after subcutaneous transplantation into nude mice. CONCLUSION: According to the rules of establishing a cell line in vitro, HCC-9903 has been proved to be a new cell line of human HCC carcinoma, and more experimental methods have been used to study its biological characteristics.

Animals↗