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Ying Zhu

Publications and source records attributed to Ying Zhu.

At least 73 records · Page 4Linked to original sources
PubMed2005

[Cyclosporin a induces titin expression in human trophoblast cells through the MEK/ERK1/2 signal pathway].

To investigate the role of MEK/ERK1/2 signal pathway in the regulation of cyclosporin A(CsA) -induced titin expression in human trophoblast cells. With RT-PCR and Western Blot, We examined the titin expression level of human trophoblast cells treated with different concentrations of CsA for various duration, then detected total ERK1/2 and phosphorated ERK1/2 level with Western Blot, and observed effect of U0126 on transcription of titin mRNA in human trophoblast cells stimulated by cyclosporin A. It was found that CsA could activate ERK1/2 in time-dependent and dosage-dependent manner, and induced titin to be expressed in human trophoblast cells. U0126, a MEK inhibitor, inhibited the transcription of titin in dosage-dependent manner. These results indicated that MEK/ERK1/2 signal pathway may play an important role in the expression of titin in human trophoblast induced by cyclosporin A.

Blotting, Western↗
PubMed2005

[Regulative action of acupuncture and moxibustion on mucosal immunity].

OBJECTIVE: To explore the regulative action of acupuncture and moxibustion on mucosal immunity and its curative effect on mucosal relative diseases. METHODS: Review the recent 10 years' achievements of studies on mucosal immunity and analyze the regulative action of acupuncture and moxibustion on the mucosal immunological system in treatment of mucosal relative diseases. CONCLUSION: Acupuncture and moxibustion has a good regulative action on local mucosal immunological system, which is one of the mechanisms of acupuncture and moxibustion in prevention and treatment of mucosal relative diseases. This proves a more reliable basis for treatment of mucosal relative diseases with acupuncture and moxibustion.

Acupuncture↗
PubMed2005

[The dynamic expression of Thy1.1 positive hepatic oval cells during the shaping and reducing processes of liver cirrhosis induced by dimethylnitrosamine in rats].

OBJECTIVES: To study the dynamic change of hepatic oval cells (HOC) in the process of rat liver cirrhosis formation induced by dimethylnitrosamine (DMN), and to explore its pathophysiology significance. METHODS: A rat cirrhosis model was established by using DMN. Microscopical and electronmicroscopical changes of HOC were examined. Thy1.1 was detected by immunohistochemical method at different times. The ratio of HOC was checked using image pattern analysis and Western blot. The number of HOC was counted microscopically. RESULTS: At the 4th week after DMN administration, the liver fibrosis was at its peak, with false lobules formation combined with large areas of hemorrhage and necrosis. The fibrosis started to minimize at the 6th week, and also the inflammatory changes at the 8th week. Thy1.1 positive stained cells dispersed at the 2nd week; increased at the 4th week around fiber septa; reached its peak at the 6th week, then decreased at the 8th week. The results of image pattern analysis, cell counting under light microscope and Western blot were constant, with the highest cell numbers at the 6th week, and dropped at the 8th week. The ultrastructure of HOC was characterized by their small sized, oval nuclei, and higher nucleus/plasma ratio. CONCLUSION: During the formation and reduction of rat cirrhosis caused by DMN, Thy1.1 stained HOC showed notable dynamic change, which may play an important role in the cirrhotic process.

Animals↗
PubMed2005

[Determination of vitamins D2, vitamin D3 in cosmetics by high performance liquid chromatography].

OBJECTIVE: A high performance liquid chromatography method was used to detect vitamins D2 and vitamin D3, which is useful to know the use of vitamins D2 and vitamin D3 in cosmetics, prohibit the influx of cosmetics containing vitamins D2 and vitamin D3 to cosmetic market, safeguard the health of consumers. METHODS: A high performance liquid chromatography method was established for determination of vitamins D2 and vitamin D3 in cosmetics. The separation condition was optimized by trying different type of columns and mobile phases. RESULTS: The experiment goes on a Alltima C18 column (250 mm x 4.6 mm I. D., 5 microm)using methanol-acetonitrile (90: 10) as mobile phase at a flow rate of 1.0 ml/min, with the column temperature 25 degrees C and detection wave 265nm. The liner range is from 0.5 mg/L to 100 mg/L with good relationship. The detection limit of vitamin D2 is 0. 12 mg/L, the precision is less than 3.8% and recovery varies from 94.2% to 101.4%, while the detection limit of vitamin D3 is 0.06 mg/L, the precision is less than 3.5% and recovery varies from 91.6% to 97.2%. CONCLUSION: The method is simple, precise and accurate, which is suitable for the determination of vitamins D2 and vitamin D3 in cosmetics.

Cholecalciferol↗
PubMed2005

[Determination of antidangdruff agent salicylic acid, zinc pyrithione, octopirox, climbazole and ketoconazole in shampoo by high performance liquid chromatography].

A high performance liquid chromatography method was established for determination of antidangdruff agent salicylic acid,zinc pyrithione, octopirox, climbazole and ketoconazole in shampoo on a C18 column using acetonitrile-metholaqueous solution (10 mmol/L KH2 PO4 and 5 mmol/L EDTANa2, pH is adjusted to 4.0 with H3 PO4) (50:10:40) as mobile phase at a flow rate of 1.0 ml/min, with the column temperature 25 degrees C and detection wave 230nm. The precision was less than 3.8% and recovery varied from 92.7% to 104.9%. The experimental results showed that the method was simple, precise and accurate.

Chromatography, High Pressure Liquid↗
PubMed2004

Nitric oxide-mediated regulation of connexin43 expression and gap junctional intercellular communication in mesangial cells.

This study investigated a potential role of nitric oxide (NO) in the regulation of gap junctional intercellular communication (GJIC). Incubation of mesangial cells (MC) with NO donor S-nitroso-N-acetylpenicillamine (SNAP) enhanced both basal and 8-bromo-cAMP-stimulated GJIC as well as expression of gap junction protein connexin43 (Cx43). This potentiating action of SNAP on Cx43 expression was mimicked by two other NO donors and significantly blocked by soluble guanylate cyclase inhibitor 1H-[1,2,4]oxadiazolo[4,3,-alpha]quinoxalin-1-1. Guanosine 3',5'-cyclic monophosphate (cGMP) analogue 8-bromo-cGMP exerted an effect similar to NO, whereas another cGMP analogue, 8-pCPT-cGMP, which selectively activates cGMP-dependent kinase without affecting cGMP-inhibited phosphodiesterase (PDE3), had no effect. Moreover, the synergistic action of NO on Cx43 expression was completely prevented by protein kinase A inhibitor H89 but not by cGMP-dependent kinase inhibitor Rp-8-Br-PET-cGMP. These results suggested a possible involvement of NO-cAMP interaction via cGMP-mediated inhibition of PDE3. Indeed, PDE3 inhibitor cilostamide caused potentiation of 8-bromo-cAMP-elicited elevations of Cx43 expression that is similar to the effect of SNAP, and an elevation of intracellular cAMP was detected in SNAP-treated cells. With the use of genetically engineered reporter MC that express secreted alkaline phosphatase under the control of the cAMP response element, significant potentiation of cAMP-elicited activation of cAMP response element by SNAP was found. This effect was abrogated in the presence of PDE3 inhibitor cilostamide. Taken together, the results suggest that NO is involved in the control of GJIC and Cx43 expression. This effect of NO is due to activation of protein kinase A via cGMP-dependent inhibition of PDE3 activity.

3',5'-Cyclic-AMP Phosphodiesterases↗
PubMed2004

WDR26: a novel Gbeta-like protein, suppresses MAPK signaling pathway.

WD40 repeat proteins play important roles in a variety of cellular functions, including cell growth, proliferation, apoptosis, and intracellular signal transduction. Mitogen-activated protein kinases (MAPKs) are evolutionary conserved enzymes in cell signal transduction connecting cell-surface receptors to critical regulatory targets within cells and control cell survival, adaptation, and proliferation. Previous studies revealed that G-protein coupled receptors (GPCRs) play important roles in the signal transduction from extracellular stimuli to MAPKs and the WD40-containing Gbeta proteins as well as Gbeta-like proteins are involved in the stimulation and regulation of the MAPK signaling pathways. Here we report the identification and characterization of a novel human WD40 repeat protein, WD40 repeat protein 26 (WDR26). The cDNA of WDR26 is 3,729 bp, encoding a Gbeta-like protein of 514 amino acids in the cytoplasm. The protein is highly conserved in evolution across different species from yeast, Drosophila, mouse, to human. Northern blot analysis indicates that WDR26 is expressed in most of the examined human tissues, especially at a high level in skeletal muscle. Overexpression of WDR26 in the cell inhibits the transcriptional activities of ETS proteins, ELK-1 and c-fos serum response element (SRE), mediated by MEKK1. These results suggest that WDR26 may act as a negative regulator in MAPK signaling pathway and play an important role in cell signal transduction.

Amino Acid Sequence↗
PubMed2004

Adoptive transfer of paternal antigen-hyporesponsive T cells induces maternal tolerance to the allogeneic fetus in abortion-prone matings.

The embryo expresses paternal Ags foreign to the mother and therefore has been viewed as an allograft. It has been shown that anergic T cells generated by blocking of the CD28/B7 costimulatory pathway with anti B7-1 and anti B7-2 mAbs can be transferred as suppresser cells to prevent allograft rejection. Little is known, however, about the in vivo function of anti-B7-treated T cells after their transfer into abortion-prone mice in the maintenance of materno-fetal tolerance. In the present study, abortion-prone CBA/J females mated with DBA/2 males were administered anti-B7-1 and anti-B7-2 mAbs on day 4 of gestation (murine implantation window). The anti-B7-treated T cells subsequently were adoptively transferred into abortion-prone CBA/J mice. We demonstrated that costimulation blockade with anti-B7 mAbs at the time of implantation resulted in altered allogeneic T cell response and overcame increased maternal rejection to the fetus in the CBA/JxDBA/2 system. The transferred anti-B7-treated T cells appeared to be regulatory, decreasing responsiveness and generating clonal deviation in maternal recipient T cells. The transferred CFSE-labeled T cells were found to reside in the spleen and uterine draining lymph nodes, and a few were localized to the materno-fetal interface of the maternal recipient. Our findings suggest that the anti-B7-treated T cells not only function as potent suppresser cells, but also exert an immunoregulatory effect on the maternal recipient T cells, which cosuppresses maternal rejection to the fetus. This procedure might be considered potentially useful for fetal survival when used as an immunotherapy for human recurrent spontaneous abortion.

Abortion, Spontaneous↗
PubMed2004

[The expression of chemokine receptors in CD56(bright) CD16- natural killer cells and the mechanism of their recruitment in decidua].

OBJECTIVE: To investigate the transcriptions of 18 chemokine receptors in human decidual natural killer (NK) cells and explore the possible mechanisms of preferential accumulation of CD56(bright)CD16(-)NK cells in decidua during first-trimester pregnancy. METHODS: Villi and decidual tissue were collected from normal pregnant women with 5 approximately 10 gestational weeks by artificial abortion. The decidual CD56(bright)CD16(-)NK cells were isolated by immune magnetic beads. The transcription levels of 18 chemokine receptors in the decidual CD56(bright)CD16(-)NK cells were assessed by reverse transcription-polymerase chain reaction (RT-PCR). After the high expression of CXCR4 and CXCR3 mRNA in these cells was found, the expression of stromal cell-derived factor-1 (SDF-1), the specific ligand of CXCR4, in first-trimester human placenta was detected by in situ hybridization and immunohistochemistry. The concentration of SDF-1alpha in the supernatant of culture of isolated trophoblast cells derived from the first-trimester human placentas was measured by ELISA. The chemotaxis of SDF-1 to decidual CD56(bright)CD16(-)NK cells was tested in Transwell, and the chemotactic activity was quantitatively examined. RESULTS: Among the 18 chemokine receptors, CXCR4 and CXCR3 were found highly transcribed in decidual CD56(bright)CD16(-)NK cells. The concentration of SDF-1alpha in the supernatant was 385 ng/L +/- 91 ng/L after trophoblast cells had been cultured for 60 hours. Both rhSDF-1alpha and supernatants in the culture of trophoblast cells exhibited chemotactic activity on decidual CD56(bright)CD16(-)NK cells. When the concentration of rhSDF-1alpha was 10 micro g/L the number of cells that entered the lower chamber of Transwell accounted for 22.9% +/- 4.3% of the total calls. CONCLUSION: First-trimester human trophoblast cells produce SDF-1, which in turn endows the trophoblast cells with the capacity to attract decidual CD56(bright)CD16(-)NK cells highly expressing CXCR4. This activity contributes to the recruitment of decidual lymphocytes and may be used at a local level to manipulate the microimmune environment at the materno-fetal interface.

CD56 Antigen↗
PubMed2004

Effect of pH on metabolic pathway shift in fermentation of xylose by Clostridium tyrobutyricum.

The effect of pH (between 5.0 and 6.3) on butyric acid fermentation of xylose by Clostridium tyrobutyricum was studied. At pH 6.3, the fermentation gave a high butyrate production of 57.9 g l(-1) with a yield of 0.38-0.59 g g(-1) xylose and a reactor productivity up to 3.19 g l(-1)h(-1). However, at low pHs (<5.7), the fermentation produced more acetate and lactate as the main products, with only a small amount of butyric acid. The metabolic shift from butyrate formation to lactate and acetate formation in the fermentation was found to be associated with changes in the activities of several key enzymes. The activities of phosphotransbutyrylase (PTB), which is the key enzyme controlling butyrate formation, and NAD-independent lactate dehydrogenase (iLDH), which catalyzes the conversion of lactate to pyruvate, were higher in cells producing mainly butyrate at pH 6.3. In contrast, cells at pH 5.0 had higher activities of phosphotransacetylase (PTA), which is the key enzyme controlling acetate formation, and lactate dehydrogenase (LDH), which catalyzes the conversion of pyruvate to lactate. Also, PTA was very sensitive to the inhibition by butyric acid. Difference in the specific metabolic rate of xylose at different pHs suggests that the balance in NADH is a key in controlling the metabolic pathway used by the cells in the fermentation.

Acetate Kinase↗
PubMed2004

The expression of CXCR4/CXCL12 in first-trimester human trophoblast cells.

Chemokines and chemokine receptors have been implicated as pivotal players in many physiological and pathological situations, but little is known about the expression and function of chemokines and chemokine receptors at the materno-fetal interface. In this study, we first analyzed the transcription of 18 chemokine receptors in first-trimester human trophoblast cells. Among these receptors, CXCR4 was found highly transcribed. We demonstrated afterward that both CXCR4 and CXCL12 (stromal cell-derived factor-1; SDF-1) were expressed in trophoblast cells. Primary cultured trophoblast cells were also found secreting CXCL12 spontaneously. To identify the functional role of CXCR4/CXCL12 in these cells, we treated trophoblast cells with recombinant human (rh)SDF-1 alpha and analyzed the cell viability and signaling pathway. The results showed that rhSDF-1 alpha increased the viability of trophoblast cells and the activation of extracellular signal-regulated kinases signaling pathway in vitro. Our findings suggest that first-trimester trophoblast cells express functional CXCR4/CXCL12, which may play an important role in early pregnancy such as stimulating trophoblast cell proliferation or differentiation in an autocrine manner.

Base Sequence↗
PubMed2004

An electrophysiological investigation of memory encoding, depth of processing, and word frequency in humans.

Memory encoding can be studied by monitoring brain activity correlated with subsequent remembering. To understand brain potentials associated with encoding, we compared multiple factors known to affect encoding. Depth of processing was manipulated by requiring subjects to detect animal names (deep encoding) or boldface (shallow encoding) in a series of Chinese words. Recognition was more accurate with deep than shallow encoding, and for low- compared to high-frequency words. Potentials were generally more positive for subsequently recognized versus forgotten words; for deep compared to shallow processing; and, for remembered words only, for low- than for high-frequency words. Latency and topographic differences between these potentials suggested that several factors influence the effectiveness of encoding and can be distinguished using these methods, even with Chinese logographic symbols.

Adult↗
PubMed2004

T13M mutation of lecithin-cholesterol acyltransferase gene causes fish-eye disease.

BACKGROUND: Lecithin-cholesterol acyltransferase (LCAT) esterifies free cholesterol (FC) in plasma and plays a crucial role in the maturation of prebeta1-HDL (lipid-poor HDL) into alpha-migrating HDL (spherical HDL). Natural mutations of LCAT gene cause familial LCAT deficiency (FLD) or fish-eye disease (FED). The relationship between mutations and their phenotypes gives important clues to the functions of specific regions of LCAT. We investigated the first homozygous case with a substitution of threonine to methionine at codon 13 (T13M) of LCAT gene. METHODS: We evaluated LCAT activity, LCAT distribution among HDL subfractions and conversion of prebeta1-HDL to alpha-migrating HDL by native two-dimensional gel electrophoresis (N-2DGE). RESULTS: The proband had corneal opacity, severe hypo-alpha-lipoproteinemia, half-normal LCAT activity and near normal cholesteryl ester/total cholesterol (TC) ratio in plasma. These features were characteristic of FED. Plasma prebeta1-HDL concentration was near normal, but not converted to alpha-migrating HDL during 37 degrees C incubation. As expected, alpha-migrating HDL (especially large particles) was markedly reduced. In the immunoblot against LCAT, the small alpha-migrating HDL from the proband had much less LCAT in this patient than in controls. CONCLUSION: T13M mutation of LCAT gene causes FED.

Adult↗
PubMed2004

LCAT-dependent conversion rate is a determinant of plasma prebeta1-HDL concentration in healthy Japanese.

BACKGROUND: Prebeta1-HDL acts as a primary acceptor of cellular cholesterol. Prebeta1-HDL is converted into alpha-migrating high-density lipoprotein (HDL) by lecithin/cholesterol acyltransferase (LCAT). We examined whether the LCAT-dependent conversion rate of prebeta1-HDL is a determinant of the plasma prebeta1-HDL concentration in healthy Japanese. METHODS: We measured the conversion half time (CHT(prebeta1)), the time required for 50% of baseline prebeta1-HDL to be changed into alpha-migrating HDL by LCAT, in 100 healthy Japanese (47 men, 53 women, 22-88 years). RESULTS: Prebeta1-HDL concentration, as determined by immunoassay, was significantly lower in younger women (<50 years, n=24) than in older women (>or=50 years, n=29) (16.8+/-3.3 vs. 21.7+/-8.0 mg/l apolipoprotein AI (apoAI), p<0.01). There was no significant difference in prebeta1-HDL concentration between younger (n=24) and older (n=23) men (21.2+/-6.8 vs. 22.5+/-6.6 mg/l apoAI). The mean CHT(prebeta1) for all subjects was 47.4+/-13.0 min, and was not influenced by gender or age. Prebeta1-HDL concentration was positively correlated with CHT(prebeta1) in both men and women, suggesting that high prebeta1-HDL levels may reflect delayed conversion of prebeta1-HDL. CONCLUSION: LCAT-dependent conversion rate is a determinant of plasma prebeta1-HDL concentration in healthy Japanese. We speculate that prebeta1-HDL concentration may be used as a metabolic marker for HDL maturation.

Adult↗
PubMed2004

Cloning, sequencing, expression, and purification of SARS-associated coronavirus nucleocapsid protein for serodiagnosis of SARS.

A novel coronavirus has been associated with a worldwide outbreak of atypical pneumonia referred to as Severe Acute Respiratory Syndrome (SARS-CoV). SARS-CoV nucleocapsid (N) protein has been cloned sequenced and expressed in Escherichia coli strain. Purified N protein was used to measure the SARS-CoV specific IgG antibodies from 16 SARS-CoV infected patients' sera and from 131 control subjects using ELISA assay. Specific antibody responses to the purified recombinant N protein after 10, 20, and 30 days of disease onset were observed in 13 of 16 (81.3%), 16 of 16 (100%) and 16 of 16 (100%) SARS patients sera, respectively. Comparison of detection results with a commercially available diagnostic kit coated with a mixture of SARS-CoV viral proteins showed 9 of 16 (56.3%), 13 of 16 (81.3%), and 15 of 16 (93.7%) positive responses, respectively. None of 131 control sera gave positive reaction in either assay. This data suggests that the N protein of SARS-CoV is immunodominant and this ELISA based test assay for detecting the SARS-CoV N antigen may hold a significant value for SARS diagnosis.

Antibodies, Viral↗
PubMed2004

Inoculation of Lactobacillus expressing hCG beta in the vagina induces an anti-hCG beta antibody response in murine vaginal mucosa.

OBJECTIVES: To test the possibility of vaccination with lactobacillus expressing hCG beta antigen administered by vaginal mucosal immunization. METHODS: A plasmid pIlac-hCG beta was constructed and then transfected into Lactobacillus casei CECT5276, which stably expressed hCG beta protein. RIA was used to detect hCG beta in the culture supernatant and cell lysate. Western blotting was performed to evaluate the expressed protein of interest. Female BALB/c mice aged 6-8 weeks received inoculations in the vagina of the recombinant L. casei CECT5276. ELISA was used to determine the anti-hCG beta IgA antibody in vaginal lavage fluid from the BALB/c mice after vaginal mucosal immunization. RESULTS: The pIlac alone appeared to have a higher efficiency than pIlac-hCG beta, and the highest transfection efficiency of both plasmids was at pulse voltages of 1200 V and 1500 V. About 78.5% of the hCG beta protein was excreted into the culture supernatant. Excretion of hCG beta was most efficient when the pH of the culture medium was adjusted to around 7.0 and the concentration of lactose was around 1%. The hCG beta protein in the vaginal lavage fluid of these BALB/c mice was positive on the third day after vaginal inoculation. Anti-hCG beta IgA antibody continued to be found in the vaginal lavage fluid for 2 weeks following a booster vaginal inoculation. The splenic lymphocytes of the mice immunized with hCG beta through the vagina underwent a proliferative reaction to hCG antigen restimulation in vitro. Interferon gamma (IFN-gamma) and interleukin (IL)-4 were secreted at higher levels after vaginal mucosal immunization of L. casei expressing hCG beta than after vaginal mucosal immunization of L. casei alone. CONCLUSIONS: Vaginal immunization of lactobacillus expressing hCG beta induced an anti-hCG beta antibody response in the murine vaginal mucosa. Induction of the antigen-specific antibodies in the reproductive tract following vaginal inoculation of recombinant lactobacillus will lead to the development of a safe, efficient, and easy-to-use form of immunocontraception.

Animals↗
PubMed2004

A model of the acid sphingomyelinase phosphoesterase domain based on its remote structural homolog purple acid phosphatase.

Sequence profile and fold recognition methods identified mammalian purple acid phosphatase (PAP), a member of a dimetal-containing phosphoesterase (DMP) family, as a remote homolog of human acid sphingomyelinase (ASM). A model of the phosphoesterase domain of ASM was built based on its predicted secondary structure and the metal-coordinating residues of PAP. Due to the low sequence identity between ASM and PAP (approximately 15%), the highest degree of confidence in the model resides in the metal-binding motifs. The ASM model predicts residues Asp 206, Asp 278, Asn 318, His 425, and His 457 to be dimetal coordinating. A putative orientation for the phosphorylcholine head group of the ASM substrate, sphingomyelin (SM), was made based on the predicted catalysis of the phosphorus-oxygen bond in the active site of ASM and on a structural comparison of the PAP-phosphate complex to the C-reactive protein-phosphorylcholine complex. These complexes revealed similar spatial interactions between the metal-coordinating residues, the metals, and the phosphate groups, suggesting a putative orientation for the head group in ASM consistent with the mechanism considerations. A conserved sequence motif in ASM, NX3CX3N, was identified (Asn 381 to Asn 389) and is predicted to interact with the choline amine moiety in SM. The resulting ASM model suggests that the enzyme uses an SN2-type catalytic mechanism to hydrolyze SM, similar to other DMPs. His 319 in ASM is predicted to protonate the ceramide-leaving group in the catalysis of SM. The putative functional roles of several ASM Niemann-Pick missense mutations, located in the predicted phosphoesterase domain, are discussed in context to the model.

Acid Phosphatase↗