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Y Zeng

Publications and source records attributed to Y Zeng.

At least 55 records · Page 3Linked to original sources
PubMed2001

The genetic events of HPV-immortalized esophageal epithelium cells.

We studied cytogenesis, telomere and telomerase, and c-myc, ras, bcl-2, and p53 genes of cells in the progressive process of immortal epithelial cells from embryonic esophagus induced by human papillomavirus (HPV). The SHEE cell line, established by us, consist of immortalized epithelial cells from the embryonic esophagus induced by genes E6E7 of HPV type 18. It was in initial malignant transformation when cultivated over 60 passages without co-carcinogens. Cells of the 10th, 31st, and 60th passages were represented in the progressive process within the immortal period. In these three stages of the cell line, the modal number of chromosome and karyotypes were analyzed. The telomere length was assayed by Southern blot methods, and the telomerase activity was analyzed by hTR and hTERT assay. C-myc, p53, bcl-2, ras genes were assayed by the multi-PCR method. The morphology of the 10th passage cells exhibited good differentiation, the 60th passage cells were relatively poorly differentiated, and the 31st passage cells differentiated in two distinct ways. The growth characteristics of the 31st and 60th passage cells were weakened at contact-inhibition and anchorage-dependent growth. Karyotypes of three cell passages belonged to hyperdiploid and hypotriploid with abnormal chromosomes +1, +3, +7, +9, +17, +18; del(1)(p32); der(4), t(4;?)(q31;?); der(5),t(5;?)(q31;?); der(13),t(13;13)(p11;q11) and others. Bimodal distribution of chromosomes with more aberrant chromosomes appeared in the 31st and 60th passage cells. Telomere length sharply shortened from normal fetal esophagus to the 10th and 31st passage step by step, but was stable from the 31st to the 60th passage and the telomerase activities measured were expressed at late two passages. p53 mutant was positive in three passages, c-myc was positive in the 31st and the 60th passage K-ras only in the last. The results reveal that changes of chromosomes, telomere length, telomerase activity and certain gene expressions are important events of HPV-immortalized esophageal epithelium cells. All of these changes occurred in dynamic progressive process. This cell line may be useful for the elucidation of the genetic mechanism of cellular immortalization.

Cell Line, Transformed↗
PubMed2001

A comparative study of telomerase activity and malignant phenotype in multistage carcinogenesis of esophageal epithelial cells induced by human papillomavirus.

To examine certain characteristics of multistep carcinogenesis, we studied telomerase activity and malignant phenotypes in the immortal, premalignant and malignant stages of esophageal epithelial cells induced by HPV. An immortalized human fetal esophageal epithelial cell line (SHEE) was induced by E6E7 genes of human papillomavirus (HPV) type 18. Cells in the 10th passage, (SHEE10), 31st passage (SHEE31), 61st passage (SHEE61) and SHEE61A which were selected and expanded from anchorage-independent growth colonies of SHEE61, were examined as follows: cell morphology by electron-microscopy; the cell cycle by flow cytometry, telomerase activity by TRAP assay, tumorigenic detection including anchorage-independent growth by soft agar culture and tumor formation by inoculating cells into SCID and nude mice, and detection of HPV18 E6E7 oncoprotein by Western blot. The morphology of the SHEE10 cells exhibited good differentiation, the SHEE60 and SHEE61A cells were relatively poorly differentiated, and the SHEE31 cells were differentiated in two distinct ways. The telomerase was activated in SHEE31, SHEE61 and SHEE61A, but not in SHEE10 cells. SHEE61 and SHEE61A cells were weakened in contact-inhibition and increased in anchorage-independent growth. Inoculated into SCID and nude mice, the cells of the earlier two passages could not develop tumors; the SHEE61 developed one tumor in four SCID mice, but not in nude mice, and the SHEE61A cells developed tumors in both strains of immunodeficient mice. HPV18 E6E7 DNA detection by Western blotting was positive in all cell passages. In the process of carcinogenesis by HPV, the cells of SHEE31 are in an immortalized state with telomerase activity. The fact that SHEE61 cells remained immortalized and also demonstrated anchorage-independent growth, reveals premalignant character; the cells of SHEE61A exhibited malignant transformation with tumor formation in mice. The results revealed that the telomerase activity, anchorage-independent growth and tumor formation in nude mice are the indicators for immortalization, premalignancy and malignancy, respectively.

Animals↗
PubMed2001

The effect of fluid shear stress on ICAM-1 expression of rat brain microvascular endothelial cells.

Intercellular adhesion molecule-1 (ICAM-1) is an adherence molecule that is an important factor in many pathophysiological processes such as atherosclerosis, thrombosis and inflammation. It is secretion of endothelial cells by a variety of biochemical stimulations. But hemodynamic forces can also induce various functional changes in vascular endothelium. Some researches have proved that shear stress can modulate the expression of ICAM-1. But most of them examine the regulation of expression of ICAM-1 in human umbilical vein endothelial cells. There is no detail on the effect of shear stress (SS) on ICAM-1 expression of microvascular endothelial cells (RBMECs). In this experiment, we use cultured rat brain microvascular endothelial cells (RBMECs). By using the parallel plate flow chamber method, we give two magnitudes of lamminar shear stresses (0.2 dyn/cm2, 0.4 dyn/cm2) for different perieods of time on the slides of cells. Immunostaining method and image analysis shows a specific upregulation in ICAM-1 expression on RBMECs, which is different from endothelial cells of other species or vascular beds. Expression of ICAM-1 is increased 0.5h after the onset of SS, and reached its highest level 4h after onset of SS, then declines after that. The effect is time-dependent, not force magnitude-dependent. Endothelial cell surface expression of ICAM-1 in the supernatants of RBMECs exposed to SS was not modified excluding the possibility that RBMECs exposed to SS synthesize factors that upregulate ICAM-1. The experiment data are relevant to the current understanding of basic mechanisms that explain the signal transudation pathway occurring inside the endothelial cells under the effect of SS.

Animals↗
PubMed2001

[Gene diagnosis of facioscapulohumeral muscular dystrophy].

OBJECTIVE: Perform gene diagnosis for Chinese facioscapulohumeral muscular dystrophy(FSHD). METHODS: Digest genome DNA with restriction enzymes EcoR I only and EcoR I associated with Bln I. Use 0.6% agarose gel electrophoresis and Southern blotting hybridization with probe P13E11. RESULTS: For FSHD patients, the sizes of EcoR I + Bln I/P13E11 DNA fragments ranged from 15kb to 33kb. For normal controls, they were over 41kb. Two presymptomatic patients were found. CONCLUSION: It is feasible to perform gene diagnosis and presymptomatic diagnosis for most Chinese FSHD patients by Southern blotting hybridization with probe P13E11, following double digestion of genome DNA with restriction enzymes EcoR I and Bln I.

Adult↗
PubMed2001

[Expression property of adhesive molecule ICAM-1 on vitro-cultured pulmonary microvascular endothelial cells under the stimuli of asthmatic serum].

It has been recognized only in the past 15 years that the major pathological mechanism of asthma is inflammation, which has a hallmark of focal leukocyte extravasation. The different recruitment behaviors of inflammatory cells depend on the expression of specific adhesive molecules on both leukocytes and endothelial cells (EC). Intercellular cellular adhesion molecule-1(ICAM-1) plays a major role. In the previous detailed in-vivo study of asthmatic models, we have proved the significant pathological increase of both the leukocyte-endothelium adhesion phenomenon and the ICAM-1 expression in the tissues of asthmatic lung. It may be due to an ICAM-1 accumulation on the microvascular endothelial cells and thus an enhancement of adhesion force during the course of disease. In this study, endothelial cells were obtained from rats by mechanical isolation of lung tissues and in vitro culture on glass. Confluent endothelial cells were incubated with serum collected from rat blood of normal and asthmatic models and were used for in vitro study of endothelial cell adhesion. The effect of pathological serum stimulation was examined on the expression of ICAM-1 of the pulmonary microvascular endothelial cells (PMEC). The expression of ICAM-1 on PMEC was measured by indirect immuno-fluorescence with flow cytometry. We found that the surface expression of ICAM-1 was obviously increased on serum-incubated EC as compared with that on the culture solution-incubated one, and that asthmatic serum increased the expression of ICAM-1 on EC to a peak in 4 hours and then decreased it rapidly, the expression level remained the same in the whole course when EC was treated with culture solution or normal serum.

Animals↗
PubMed2001

[Structure and function of pancreatic microcirculation].

To gain an insight into the relationship between structure and function in pancreatic microcirculation, observations were carried out in 9 corpse, 30 monkeys, 24 dogs, 62 Wistar rats and 24 rabbits by the use of scanning electron microscopy and light microscopy with the technique of retaining microcirculatory dynamic and tissular information in the static specimens, and/or by intravital fluorescence microscopy with FITC-labeled erythrocytes. The results showed: there were two capillary beds destined for the endocrine and exocrine parts of pancreas between the intralobular arteriole and venule; the blood of pancreatic portal circulation flowed from the endocrine to the exocrine part; each pancreatic lobule was supplied by a single centrally located intralobular artery and there was no anastomosis between the intralobular arterioles or any of their branches, so they were end arteries; the physiological blood flow was about 1.18 +/- 0.05 nl/min per capillary with stable capillary perfusion pattern; a profound decreased functional capillary density and capillary perfusion was observed in the early phase of acute pancreatitis. These results suggest that pancreatic lobule is a structured and functional basic unit of pancreatic microcirculation, insulo-acinar portal circulation represents the basic feature of the pancreatic microcirculation, and the intralobular arteriole, being an end artery, forms the anatomical basis of the pancreatic microcirculatory disturbance during acute pancreatitis.

Adult↗
PubMed2001

[Therapeutic potential of recombinant adenovirus expressing p53 in hepatocellular carcinoma cell lines].

OBJECTIVE: To investigate the effects of the recombinant adenoviral vector Ad-p53 on the biological behavior of hepatocellular carcinoma (HCC) cells in vitro and in vivo. METHODS: With recombinant adenoviral vector expressing WT-p53 (Ad-p53), p53 gene was transfected into the HCC cell line, PLC/PRF/5. The cytotoxicities of Ad-p53 to cells were measured by MTT assay. Cell growth properties and cell cycle patterns were assessed with flow cytometry. The animal model was developed by injecting HCC cells into the dorsum of nude mice. Ad-p53 was injected intratumorally. The animals were killed, and then excised tumors were weighed and analyzed for p53 and p21 protein expression using western blot assay. RESULTS: The introduction of exogenous wild-type p53 resulted in the inhibition of cell growth, high G2/M ratio and cell apoptosis, and low S ratio in PLC/PRF/5. The expression of both p53 and p21 proteins was upregulated in the cells. CONCLUSIONS: Replication-deficient adenoviral vector expressing WT-p53 may be useful for gene therapy of HCC.

Adenoviridae↗
PubMed2001

Mechanosensitive channel currents recorded in rat microvascular endothelial cells with whole-cell mode.

Using the whole-cell patch-clamp technique, we recorded delayed outward currents in rat brain microvascular endothelial cells (BRMECs), which were nearly completely inhibited by 20 mmol/L extracellular TEA-Cl and 5 mM extracellular CsCl. Whole-cell currents were elicited under voltage clamp condition by 2100 ms depolarizing voltage pulses applied every 7 s between -100 to 90 mV in 10 mV increment from a holding potential of -100 mV. The currents were defined as delayed rectified K+ currents (IKv), which were inhibited in a concentration-dependent manner by bath application of TEA-Cl, with an IC50 approximately 2.0 mM, similar to that reported on IKv in other preparations. In the present of mechanical force, outward currents were increased in amplitude as compared with controls. These mechanical force induced currents were also defined as IKv, which are different from previous described mechanosensitive currents with characteristic of inward rectifier.

Animals↗
PubMed2001

[Syphilis in pregnancy women].

OBJECTIVE: To investigate obstetric treatment and pregnancy outcomes of syphilis infection during pregnancy. METHODS: 64 pregnant women diagnosed with syphilis by serological assays were divided into treated group and untreated group according to whether they accepted full-dose treatment against syphilis or not. Patients in the treated group accepted benzathine penicillin(2.4 million units once per week) intramuscular injection for three weeks. The outcome of pregnan after treatment was observed and compared between the two groups. RESULTS: There were 5 cases of primary syphilis (7.8%), 29 cases of secondary syphilis (45.3%), and 30 cases of latent syphilis (46.9%) among the 64 cases. The occurrences of premature birth, fetal intrauterine death, and stillbirth were 0, and 3 cases of congenital syphilis in total 13 cases who carried pregnancy to term in the treated group; while 4, 11, 3, and 10 in the untreated group respectively. In treated group, the 3 babies with congenital syphilis were born from 10 mothers received treatment after 24 gestational weeks, while no congenital syphilis in the 3 women started treatment before 24 weeks. CONCLUSIONS: Pregnant syphilis is prone to be misdiagnosed because of its slight symptom, so it is especially important to screen syphilis as a routine among high risk pregnant women. Premature, fetal death and congenital syphilis can be well controlled through regular and early treatment during pregnancy, yet congenital syphilis can not be avoided completely.

Adolescent↗
PubMed2001

[Modulating effects of thymopentin on the immune system of severely burned patients].

OBJECTIVE: To explore the modulating effects of thymopentin (TP-5) on the immune system of severely burned patients. METHODS: Sixty patients with severe burn were enrolled in this study and were randomly divided into treatment (T, n = 30) and control (C, n = 30) groups. The T lymphocytes and NK cells in peripheral blood in two groups were determined on the 2, 5, 8, 15 and 22 postburn days (PBDs). The patients in T group were treated with TP-5 in a dose of 1 mg/d for 20 days beginning on 2 PBD. RESULTS: There was no difference of T lymphocytes and NK cells between the two groups on 2 PBD, and there was no difference of total number in T lymphocytes between the two groups on 5, 8, 15 and 22 PBDs. But the NK cell number and CD4/CD8 ratio in C group were much lower than those in T group. CONCLUSION: The function of T lymphocytes and NK cells in severely burned patients could be obviously improved by TP-5, which played immune modulating roles.

Adjuvants, Immunologic↗
PubMed2001

Novel chromosomal alterations detected in primary nasopharyngeal carcinoma by comparative genomic hybridization.

OBJECTIVE: To gain a better understanding of genetic changes in Cantonese nasopharyngeal carcinoma (NPC). METHODS: Comparative genomic hybridization (CGH) was performed on 17 primary nasopharyngeal carcinomas. RESULTS: A novel copy number gain an chromosome 4q and loss of chromosome 1p were found at a high frequency (> 50%). CONCLUSIONS: Current analysis revealed a comprehensive profile of the chromosomal regions showing gain of chromosomes 4q, 12q, and 1q as well as loss of chromosomes 1p, 3p, 11q, 14q, 15q, 13q, Xq, 9q, 10p, 10q, and 16q. Frequently altered loci may encode oncogenes or tumor suppressor genes involved in the development of primary NPC.

Chromosome Aberrations↗
PubMed2001

[The mechanism of percutaneous transluminal balloon angioplasty as assessed by intracoronary ultrasound].

OBJECTIVE: To elucidate the mechanism of coronary balloon angioplasty intracoronary ultrasound imaging. METHOD: Intracoronary ultrasound imaging was performed in 68 coronary arteries of 52 patients. Ultrasound images obtained at the treatment site before and after balloon angioplasty were analyzed quantitatively for cross-sectional lumen area, area enclosed by internal elastic lamina (IELA) and plaque area. Qualitative analysis included assessment of presence of dissection, plaque composition and plaque topography. RESULTS: The internal elastic lamina area was significantly enlarged after balloon angioplasty [(6.67 +/- 1.45) mm(2) vs (8.14 +/- 1.13) mm(2), P < 0.05]. The difference between IELA before and after balloon angioplasty DeltaIELA was different among different plaques (fatty plaque 1.84 mm(2), fibrous plaque 1.52 mm(2), calcified plaque 0.40 mm(2), mixed plaque 1.23 mm(2)). 85% of the lesions had dissection in some degree after PTCA. Severe dissections occurred mostly in calcified lesions. CONCLUSION: The improvement in lumen dimensions after coronary balloon angioplasty is a result of both vessel stretch, as demonstrated by a larger internal elastic lamina area at the treated site, and dissection. Calcified lesions will have less vessel stretch and severer dissection after balloon angioplasty.

Adult↗
PubMed2001

[Study on mutations of beta chain of high-affinity IgE receptor gene in people of Han nationality of southern China].

OBJECTIVE: To detect mutations of beta chain of high-affinity IgE receptor (Fc epsilon RI-beta) gene and analyze the association between its mutation and asthma in people of Han nationality of southern China. METHODS: Amplification refractory mutation system-polymerase chain reaction technique was used to determine 3 mutations (I181L, V183L and E237G) at Fc epsilon RI-beta gene in 60 unrelated patients with asthma and 65 healthy controls from people of Han nationality of southern China. RESULTS: (1) The mutation V183L was not detected in patient and control groups. (2) The only one heterozygous for I181/L181 was found in patient group, and no homozygous for L181/L181. (3) The frequency of Glu237/Gly237 genotype is 18.3% in patient group, and 6.2% in control group. The frequency of Gly237 gene is 9.2% in patient group, and 3.1% in control group. (4) There was a significant difference in the frequencies of Glu237/Gly237 genotype and Gly237 gene. CONCLUSION: These results suggest that E237G mutation of Fc epsilon RI-beta gene presents in people of Han nationality of southern China, and is correlated with asthma. There are the lack or very low frequencies of V183L and I181L mutations in people of Han nationality of southern China.

Adolescent↗
PubMed2001

[Calcium-binding protein S100A2 in the retardation of growth and proliferation of hepatocellular carcinoma cells].

OBJECTIVE: To study the retardation effect of calcium-binding protein S100A2 on the growth and proliferation of hepatocellular carcinoma QGY7701 cells. METHODS: After the plasmid of EGFP-S100A2 had been regrouped and introduced into the hepatocellular carcinoma QGY7701 cells with lipofectin, the expression and location of the products were observed by fluorescent microscopy. The cell growth and proliferation were monitored through cell colony formation in vitro and xenografting subcutaneously in the nude mice in vivo. The effect of S100A2 on the QGY7701 cell cycle was examined with flow cytometry. RESULTS: The chimera protein of S100A2 and green fluorescent protein were detected and appeared to be localized in the cytoplasm and nucleus, while the green fluorescent protein was found to be localized only in the cytoplasm. The cell colony formation of QGY7701/A2 was significantly reduced as compared with the controls. The xenografted tumor of QGY7701/A2 in the nude mice showed a growth at a considerably slower rate than that of QGY7701/pc and QGY7701 groups. The cell cycle review showed retardation of QGY7701/A2 cells in the G1 phase and the DNA content was obviously reduced as compared with the controls. CONCLUSION: The exogenous S100A2 is able to check the QGY7701 cell cycle, stop the cell growth and proliferation either in vitro or in vivo in the QGY7701 cells.

Animals↗
PubMed2001

[Expression and significance of urokinase-type plasminogen activator, its receptor, and type 2 inhibitor in giant cell tumor of bone].

OBJECTIVE: To investigate the expression and significance of u-PA, u-PAR and PAI-2 mRNA in giant cell tumor of bone. METHODS: The expressions of u-PA, u-PAR and PAI-2 mRNA in 42 patients with giant cell tumor(GCT) of bone was detected with in situ hybridization. RESULTS: The expression rates of u-PA, u-PAR, and PAI-2 mRNA of multinuclear giant cells (MGC) were 64.3%, 71.4% and 40.5%. Their expression rates in the mononuclear cells (MC) were 54.8%, 45.2% and 9.5%, respectively. The expression rates of u-PA mRNA in MGC, u-PA and u-PAR mRNA in MC of grade II and III lesions were significantly higher than those of grade I and non-recurrent lesions (P < 0.05). Close positive relation was observed between the expressions of u-PA mRNA of both cells, between the expressions of u-PAR and PAI-2 mRNA in MGC and also between the expressions of u-PA and u-PAR mRNA in MC. The expression rate in MGC was higher than that of MC significantly (P < 0.05). CONCLUSION: The expressions of u-PA, u-PAR mRNA of giant cell tumor, especially in the mononuclear cells demonstrate lower differentiation and recurrent potential in giant cell tumor of bone. Mononuclear cells may be the main tumor cell in giant cell tumor of bone.

Bone Neoplasms↗
PubMed2001

[The effects of sodium butyrate on proliferation, differentiation and apoptosis in immortalized esophageal epithelial cells].

OBJECTIVE: To study the effects of sodium butyrate on proliferation, differentiation and apoptosis of immortalized esophagus epithelial cells. METHODS: SHEE, an immortalized human fetal esophageal epithelial cell line induced by HPV18 E6E7, was cultivated in culture flasks and 24-well plates. Two experiment groups of cultured cells were treated with 1 and 5 mmol/L of sodium butyrate respectively for 4 days, and one group of untreated cells set aside as control. The numbers of cloned cells were calculated. The ultra-structure of SHEE cells was examined by transmission electron microscopy (TEM). The cell cycle and number of apoptotic cells were measured by flow cytometry, Ki-67 and cytokeratin of cells were detected by immunohistochemistry method and F-actin of cells labeled with phalloidin was examined by laser confocal scanning microscopy. RESULTS: Colony formations showed a significant decrease in the 2 experiment groups after 4 days of culture (P < 0.01). In the 1 mmol/L group, the cells at S phase were diminished and arrested at G(0)/G(1) phase. Compared with control group, Ki-67 positive cells were found decreased, while F-actin and cytokeratin were increased. Apoptotic cells in 5 mmol/L group were increased markedly. CONCLUSIONS: Sodium butyrate may induce SHEE cells growth arrest, differentiation and apoptosis. The effects depend on sodium butyrate concentration and time of exposure. Whether it can be used in combination with other anticancer drugs should be further studied.

Actins↗
PubMed2001

Biorheological characteristics of skin after expansion.

This study investigated the changes in biorheological characteristics of skin after expansion. Expanders were implanted into the back of eight adult dogs, and after an eight-week expansion the expanded and the non-expanded control skins were transferred to an adjacent site. The expanded specimens and their controls were obtained at 3, 6, 12 and 24 weeks after transfer, and their biorheological characteristics and histological changes were studied. The characteristics of the stress-relaxation, the stress-strain relationship and tensile strength of the expanded and control specimens were measured. The tests demonstrated that during the initial stage after transfer, the biorheological properties of experimental specimens differed significantly from those of their controls. However, the differences between expanded and control specimens began to lessen gradually with increasing recovery time. When the recovery time reached 24 weeks or longer, the experimental skin exhibited the same mechanical properties as the control skin. Histological examination of expanded specimens showed thickened epidermis and thinned dermis. But there were no significant histological differences between expanded skins and their controls after 24 weeks.

Animals↗