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Biomedical subjects

J Zheng

Publications and source records attributed to J Zheng.

At least 109 records · Page 6Linked to original sources
PubMed2001

[Culture and identification of fetal human retinal photoreceptors].

OBJECTIVE: To investigate the methods of isolation and culture of fetal human retinal photoreceptors. METHODS: Fetal human retinal photoreceptors were obtained by enzyme gradation digestion, cultured in media conditioned by retinal pigment epithelial cells (RPE-CM), identified by morphologic observation and immunohistochemically stained with rod specific opsin 4D2 (Rho 4D2) antibody. The digested retinal tissues were tested by hematoxylin-eosin (HE) staining. RESULTS: Enzyme gradation digestion could obtain relatively pure retinal photoreceptors. These cells were stained positively for Rho 4D2 antibody, and survived in RPE-CM for a long time. CONCLUSION: Fetal human retinal photoreceptors obtained by enzyme gradation digestion can survive in RPE-CM for a long time and express rod specific opsin. This culture system will provide a source for human retinal photoreceptor transplantation and further studies of photoreceptors in vitro.

Cell Division↗
PubMed2001

[Primary research about reconstruction of cornea in three-dimensional collagen gel in vitro].

OBJECTIVE: To research the reconstruction of cornea in three-dimensional culture. METHODS: Using primary cultured corneal epithelial cells, stromal cells and endothelial cells rebuilt a corneal structure in three-dimensional collagen gel reconstruction system. The artificial corneal transparency was examined by a slit-lamp microscope. The biological characters of cells were tested by routine pathologic and transmission electron microscopic technology. RESULTS: The reconstructed corneal tissue formed three layers. The epithelial cell layer was two or three cell thickness. The endothelial cells formed a single layer. The stromal cells were diffuse in distribution in the collagen gel. The cells had proliferative ability and capability of producing collagen. CONCLUSION: The regular and transparent corneal structure can be rebuilt by tissue engineering technology.

Cells, Cultured↗
PubMed2001

[Activation of p38 and c-Jun NH2-terminal kinase mitogen-activated protein kinases in human prostate carcinoma cell lines with different metastatic potentials].

OBJECTIVE: To investigate the influence of P2 purinoceptor agonist ATP on p38 mitogen-activated protein kinases (MAPK) and JNK (c-Jun NH(2)-terminal kinase) signaling pathway in two human prostate cancer cell sublines (1E8 and 2B4) with different metastasis potentials. METHODS: Activated p38 and JNK were detected by Western blot with phospho-specific antibodies directed against the dually phosphorylated active forms of p38 or JNK. RESULTS: Exposure of 1E8 and 2B4 prostate cancer cells to ATP resulted in p38 activation in a concentration- and time-dependent manner. ATP-induced p38 activities were higher in metastatic 1E8 cells when compared with nonmetastatic 2B4 cells. JNK signaling pathway was not activated by ATP. An MEK inhibitor PD 98059 failed to inhibit ATP-induced p38 activation, while p38 inhibitor SB 203580 and P2 purinoceptor antagonist suramin effectively inhibited activation of p38, the inhibition rate being 1E8 83% and 79%, 2B4 81% and 69%. The response of ATP-stimulated p38 to G-protein modulator pertussis toxin in 1E8 and 2B4 cells was not obvious. CONCLUSIONS: p38 but not JNK signaling pathway can be activated by P2 purinoceptor agonist ATP. Differences of p38 activation by ATP are noted between metastatic 1E8 cells and non-metastatic 2B4 cells. These results provide instructive clues to cancer malignant growth and metastasis research.

Adenosine Triphosphate↗
PubMed2001

[Detection and analysis of SYT-SSX fusion gene in synovial sarcoma].

OBJECTIVE: To demonstrate that a characteristic SYT-SSX fusion gene resulting from chromosomal translocation t (X; 18) (p11; q11) was detectable in archival paraffin-embedded synovial sarcoma tissues. METHODS: SYT-SSX fusion transcripts in 20 synovial sarcomas (histologic subtypes, 15 monophasic and 5 biphasic) were detected and analyzed by the reverse-transcriptase polymerase chain reaction and compared with the results from relevant pathological data. RESULTS: A specific SYT-SSX RT-PCR product was found in 19 of 20 (95%) synovial sarcomas tested and of the 13 tumors containing SYT-SSX2, 10 were monophasic. CONCLUSION: SYT-SSX fusion transcripts are considered as a defining diagnostic marker of synovial sarcomas and the subtypes of SYT-SSX fusion transcripts (SYT-SSX1 and SYT-SSX2) may yield prognostic information.

Adolescent↗
PubMed2001

[The management of bony burn with skin flap transplant with preservation of sequestrum].

OBJECTIVE: To study the management of bony burn, so as to improve the quality of bony burn treatment, to decrease the complications and to shorten the course. METHODS: Retrospective review of 36 cases with bony burn cured since 1992 was done in terms of treatment strategy before skin flap transplant to cover the burn wound, i e sequestrum preserved or partial removal. RESULTS: There exhibited no complications, such as infection, osteomyelitis and pathologic bone fracture in all these cases. CONCLUSION: The treatment strategy described here could be advocated in view of its reliable coverage of the wound, shortening of the bony burn course and reduction of complication.

Adolescent↗
PubMed2001

[An experimental study on the release of endotoxin from gram negative bacteria induced by antibiotics].

OBJECTIVE: To explore the characteristics and possible mechanism of LPS released from Gram negative bacteria induced by antibiotics, so as to improve clinical management of endotoxemia and sepsis. METHODS: Cultures containing PA103 subtype of Pseudomonas aeruginosa (PA) and E coli 25922 subtype of E coli were treated with four kinds of antibiotics as Imipenam (IMP), ceftazidime (CTZ), amikacin (AMN) and pefloxacine (PFX) in four concentrations of 0.5, 1, 5 and 10 MIC for 8 hours. The changes in the bacterial quantity and morphology and the supernatant levels of free LPS of the culture media were observed at different time points. RESULTS: All the four kinds of antibiotics could kill the tested bacteria in similar degree, but lead to the different types of morphological changes of the bacteria. In detail, IMP could convert the bacteria into spherical shape, while CTZ and PFX made the bacteria to filamentous shape. But AMN could induce lysis of bacterial thallus. Under same condition, the ability of different kinds and concentrations of antibiotics to induce LPS release ranked as CTZ > PFX > IMP > AMN, 0.5MIC > 1MIC > 5MIC > 10MIC. Along with the prolongation of the action time, the LPS release increased. Furthermore, PA103 released less endotoxin than E. coli after the action of antibiotics. CONCLUSION: All of the four antibiotics, i,e, IMP, CTZ, AMN and PFX could induce PA103 and E coli 25922 to release different levels of LPS, which was related to bacterial morphological changes. The LPS release from the bacteria was correlated to the antibiotics applied, concentrations, action time and the bacterial features. Antibiotics with less ability of inducing LPS release were recommended for clinical management of the sepsis and/or septic shock caused by Gram negative bacteria.

Amikacin↗
PubMed2001

[The effect of Lipopolysacharide (LPS) on morphology and function of human umbilical endothelial cells (HUVECs)].

OBJECTIVE: To study the effects of LPS on the morphology and function of HUVECs, so as to explore the roles of activated vascular endothelial cells (VEC) by LPS in systemic inflammatory reaction, sepsis and MOF. METHODS: HUVECs primarily cultured in vitro were employed as the model. Inverted microscope was used to observe the effects of LPS on the morphology of HUVECs. ELISA was used to assess the IL-6 content. The expression of ICAM-1 was determined by immunofluorescent staining method with confocal laser-scanning fluorescence microscope. RESULTS: The morphology of HUVECs could be altered by LPS to become long cord-like in shape. The smallest dose of LPS for stimulating the secretion of IL-6 from HUVEC was 1 ng/ml, and the effect was enhanced parallel to the increase of the concentration of LPS and reached top level at 8 postburn hours. The expresson of ICAM-1 on the nucleic and cytoplasmic membrane of HUVECs increased obviously after HUVECs was cultured with LPS (10 ng/ml) for 24 hours when observed by laser confocal scanning light microscope. CONCLUSION: The morphology and function of HUVECs could be evidently affected by LPS. As a result, LPS might play important roles in the increase of vascular permeability, the promotion of leukocytic adherence, and the initiation of inflammatory cascade reaction.

Cell Line↗
PubMed2001

[The effects of gut -- origin lipopolysaccharide translocation on the apoptosis of lymphocytes in scalded rats].

OBJECTIVE: To investigate the relationship between lymphocyte apoptosis in spleen and mesenteric lymph nodes (MLNs) and gut -- origin lipopolysaccharide (LPS) translocation after severe scalding in rats. METHODS: Wistar rats inflicted 30% TBSA III degree scalding were employed as the model. Serum LPS levels in portal vein and vena cava were determined by limulus amebocyte lysate (LAL) test. Apoptotic lymphocytes in paraffin -- embedded spleen and MLNs sections were detected with TdT -- mediated and dUTP nick end labeling (TUNEL) and peroxidase (POD) staining. The images were taken by cooldccd camera system, and the count and optical density (OD) value of apoptotic lymphocytes were analyzed with software Spot and Imagine proplus 4.10a (IPP4.10a). RESULTS: Serum LPS levels in portal vein and vena cava increased sharply in rats postburn (P < 0.01) and reached a peak value at 6 postburn hour (PBH). LPS level in portal vein was higher than that in vena cava (P < 0.01) in the period of 3 to 48 PBHs. The results of TUNEL -- POD staining and the count of apoptotic lymphocytes showed that the apoptotic cells were few in normal MLNs, but increased obviously postburn (P < 0.01), especially at 3 PBH. On the contrary, apoptotic lymphocytes were concentrated in spleen cortex before injury and decreased obviously postburn (P < 0.01), though a slight recovery was found after 24 PBH. Optical density of apoptotic lymphocytes was significantly reduced in spleen at 24 PBH, But the OD value of apoptotic lymphocytes in MLNs increased significantly within 48 PBHs when compared with that before injury (P < 0.01). CONCLUSION: Gut -- origin endotoxemia in rat could occur in early postburn period. The LPS translocation might induce lymphocyte apoptosis in MLNs. The decreased apoptotic lymphocytes in spleen implied abnormal immune function in spleen.

Animals↗
PubMed2001

[Introduction of ancient Bencao works stored overseas yet not included in Quanguo Zhongyi Tushu Lianhe Mulu (National Coalition Catalogue of TCM Works)].

This paper briefly introduces 14 ancient Bencao works stored overseas yet not included in Quanguo Zhongyi Tushu Lianhe Mulu, with the information, including the authors, accomplish date, number of volume, categories, quantity of drugs, characteristics of content, store sites, and the condition of returned duplicated edition in China, and etc. Among the 14 works, 2 were accomplished in the Yuan dynasty, 9 in the Ming dynasty and 3 in the Qing dynasty.

Books↗
PubMed2001

[Effect of xanthnotoxol on contractility of isolated rabbit ileum].

OBJECTIVE: To study the effect of Xanthnotoxol on contractility of isolated rabbit ileum and its relationship with Ca2+. METHOD: Routine experimental methods for isolated ileum were adopted. RESULT: Xanthnotoxol (XT) and Verapamil (Ver) inhibited the contraction of isolated rabbit ileum smooth muscle induced by submaximal concentrations of acetylcholine (ACh) and serotonim (5-TH), with a IC50 value (mumol.L-1) of 10.495 +/- 1.521, 0.428 +/- 0.001 and 18.132 +/- 1.627, 0.249 +/- 0.003, respectively. XT and Ver inhibited the contraction induced by Ca2+ after high K+ depolarization and for noncompetitively antagonist CaCl2 cumulative dose-response curve, the pD'2 value was 4.69 +/- 0.03 and 6.35 +/- 0.10, respectively. XT (10 mumol.L-1) and Ver(0.06 mumol.L-1) inhibited the contraction induced by ACh in Ca(2+)-free medium, while XT (100 mumol.L-1) but not Ver(0.6 mumol.L-1) inhibited the extracellar CA(2+)-dependent contraction induced by ACh. CONCLUSION: XT has a calcium-antagonistic effect which was not similar to that of Ver.

Animals↗
PubMed2001

[Nasal cavity dimensions in the infants measured with acoustic rhinometry].

OBJECTIVE: To investigate the range of normal value of minimal cross-sectional area (MCA) of the nasal cavity, distance of minimal cross-sectional area from the nostril (DCA), total nasal cavity volume(NV) and total nasopharyngeal cavity volume (NPV) of healthy infants. METHOD: One hundred and seventy-five healthy infants and one hundred and eight infants suffered from acute upper respiratory tract infection were measured with acoustic rhinometry. RESULT: The range of total MCA of healthy infants was 0.2-0.5 (cm)2, DCA was 1.93-2.47 cm, NV was 2.69-4.75 cm3 and NPV was 3.83-8.92 cm3. Comparing healthy infants with infants suffered from acute upper respiratory tract infection, there all were significant differences in MCA, DCA and NV. CONCLUSION: Acoustic rhinometry suit objective assessment of the nasal airways in infants. It is demonstrated that these data can provide available information for the study of nasal physiology and pathophysiology, well as for the diagnosis and judgement of therapeutic effectiveness of nasal diseases.

Child, Preschool↗
PubMed2001

[Amplifying variable region gene of light chain of monoclonal antibody against human retinoblastoma by PCR].

OBJECTIVE: To acquire the variable region gene of light chain of monoclonal antibody against human retinoblastoma. METHODS: Total RNA were extracted from hybridoma cells secreting specific monoclonal antibody(McAb) against human retinoblastoma(RB), then transcripted reversely into cDNA with random primers. The variable region of the light chain(VL) gene fragments were ampliflied using polymerase chain reaction(PCR) method. Agrose gel electrophoresis was confirmed. RESULTS: 1.5% agrose gel electrophoresis indicated that VL gene was about 340 base pairs. CONCLUSION: The light chain variable region gene of the McAb against human RB was amplified successfully, which lays a good basis for construction of a recombinant antibody.

Antibodies, Monoclonal↗
PubMed2001

[Influence of cell cycle in human trabecular cells induced by dexamethsone].

PURPOSE: To investigate the influence of dexamethesone (Dex) on cell cycle in human trabecular cells(HTC). METHODS: The trabecular specimens from human eyes were cultured in vitro. Then the cultured cells were immersed in DMEM solution containing 10(-7) M dexamethesone for three, five and seven days. The cell cycle was detected by Flow Cycometry. RESULTS: The G2 phase of cell cycle in HTC increased when HTC were treated by Dex. The G2 phase was 2% in control group. For three, five and seven days treated by Dex, the G2 phase were 8%, 16.3 and 19.4%. CONCLUSION: The influence of cell cycle might be induced by Dex, it may be related with the pathogenesis of glucocorticoid induced glaucoma.

Cell Cycle↗
PubMed2001

[Study on the dynamic changes of retinoblastoma gene of SO-Rb50 cell line].

PURPOSE: To study the dynamic changes of Retinoblastoma Gene of SO-Rb50 cell line. METHODS: 1) Southern blot hybridization was used to analyse the tumor cell DNA of 327th passage of SO-Rb50 cell line. 2) A promoter and 27 exons of Rb gene were screened exon-by-exon by using PCR-SSCP at 415th and 713th passages of SO-Rb50 cell line. 3) Three cell cloning strains named as MC2, MC3 and MC4 were isolated by single cell cloning technique from the SO-Rb50-775, and mutation of Rb gene were also screened exon-by-exon by using PCR-SSCP-HA in MC2-11, MC3-11, MC4-11 and MC3-138. RESULTS: The 3.5 Kb, 2.9 Kb and 1.0 Kb bands were deleted in the DNA of SO-Rb50-327 tumor cells, showing the deletion of Rb gene in SO-Rb50 cell line. Exon23 of 451th passage cells decreased one band; but exon 25 of 713th passage cells decreased two bands, indicating that exon 25 had new mutation. PCR-SSCP-HA analysis of exon24 showed that MC4-11 and MC3-138 had abnormal bands, but MC2-11 and MC3-11 weren't found mutation of Rb gene. This result suggested that new mutation occurred to exon24 of MC3 during a long-term culture in vitro. CONCLUSION: Retinoblastoma gene mutation of SO-Rb50 cell line had dynamic changes during a long-term culture.

Exons↗
PubMed2001

[The study on effects of rhEGF on proliferation of human conjunctival epithelial cells].

PURPOSE: To investigate the effects of Recombinant Human Epidermal Growth Factor (rhEGF) on proliferation of human conjunctival epithelial cells and optimal dose in vitro. METHODS: Cultured human conjunctival epithelial cells were plated in 96-well plates at a density of 2,000 cells per chamber, treated with different concentrations of rhEGF (100 micrograms/ml, 50 micrograms/ml, 20 micrograms/ml, 10 micrograms/ml, 5 micrograms/ml and 1 microgram/ml). After 24, 48, 72 and 96 hours of treatment, cell viability was assessed with MTT assay. RESULTS: There was no significant difference in all experimental groups and the control group in the first 24 horus. Experimental groups at a concentration of 50 micrograms/ml, 20 micrograms/ml and 10 micrograms/ml had significantly higher cell viability than which of the control group 48 hours later. All groups of rhEGF had significantly higher cell viability than which of the control group after 72 hours treatment, except for 100 micrograms/ml of rhEGF. Each group of rhEGF after 96 hours treatment had higher cell viability than which of the control group, and 100 micrograms/ml of rhEGF had lower cell viability than which of the other experimental groups, with significant difference. CONCLUSION: rhEGF enhance proliferation of human conjunctival epithelial cells effectively in vitro. The optimal concentration ranged from 10 micrograms/ml to 50 micrograms/ml.

Cell Division↗
PubMed2000

Regioselective substitution of fluorine in F(8)BINOL as a versatile route to new ligands with axial chirality

Nucleophilic substitution of aromatic fluorine in F(8)BINOL offers the possibility of selectively introducing a variety of substituents at the 6, 6', 7, and 7' positions. The configurational integrity of the homochiral precursors is maintained under the conditions described, allowing one to carry out these modification protocols on a microscale without the need for subsequent resolution steps. The resulting chiral ligands have been investigated as precursors to new asymmetric catalysts.

Journal Article↗
PubMed2000

Photoelectrochemical Response of Langmuir-Blodgett Monolayer Films Containing Donor-pi-Acceptor Azomethine Dyes.

Three amphiphilic azomethine dyes, (E)-N-octadecyl-2-[2-(4-N, N-dimethylaminophenyl)azomethinyl]quinolinium tiodide, (E)-N-octadecyl-4-[2-(4-N, N-dimethylaminophenyl)azomethinyl]quinolinium iodide, and (E)-N-octadecyl-6-[2-(4-N, N-dimethylaminophenyl)azomethinyl]quinolinium iodide, have been prepared by changing different relative positions of electron-accepting groups. They were successfully transferred onto indium-tin oxide slides by the Langmiur-Blodgett (LB) technique. Photoelectrochemical studies on these dyes' LB monolayer-modified ITO electrode were carried out. In 0.5 M KI solution containing 0.05 M I(2), the photocurrent generation quantum yield for these dyes varied from 7.2 to 15.9%, depending on the linking positions. Dependence of the photocurrent on the applied potential and the redox couple suggests that they undergo the photoinduced electron transfer mechanism of photoelectric conversion. Copyright 2000 Academic Press.

Journal Article↗