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Yue Zhang

Publications and source records attributed to Yue Zhang.

At least 109 records · Page 6Linked to original sources
PubMed2003

An important role for RUNX3 in human L1 transcription and retrotransposition.

LINE-1s (long interspersed nuclear elements-1) are abundant non-LTR retrotransposons that comprise 17% of the human genome. The 5' untranslated region (5'UTR) of human L1 (L1Hs) houses a poorly understood internal promoter. Here we report that mutations at a putative runt-domain transcription factor (RUNX) site (+83 to +101) in the 5'UTR decreased L1Hs transcription and retrotransposition in cell culture-based assays. Exogenous expression of RUNX3, but not the other two RUNX family members, RUNX1 and RUNX2, increased L1Hs transcription and retrotransposition, which were otherwise decreased by siRNAs targeting RUNX3 and a dominant negative RUNX. Further more, the specific interaction between RUNX3 and its binding site was demonstrated by an electrophoretic mobility shift assay (EMSA) using an anti-RUNX3 antibody. Interestingly, RUNX3 may also regulate the antisense promoter activity of L1Hs 5'UTR via another putative RUNX site (+526 to +508), as revealed by site-directed mutations and exogenous expression of RUNX factors. Our results indicate an important role for RUNX3 in L1Hs retrotransposition as well as transcription from its 5'UTR in both sense and antisense directions, and they should contribute to our understanding of the mechanism underlying L1Hs retrotransposition and its impact on the expression of adjacent cellular genes.

5' Flanking Region↗
PubMed2003

Functional divergence of human cytoplasmic myosin II: kinetic characterization of the non-muscle IIA isoform.

Cytoplasmic (or non-muscle) myosin II isoforms are widely expressed molecular motors playing essential cellular roles in cytokinesis and cortical tension maintenance. Two of the three human non-muscle myosin II isoforms (IIA and IIB) have been investigated at the protein level. Transient kinetics of non-muscle myosin IIB showed that this motor has a very high actomyosin ADP affinity and slow ADP release. Here we report the kinetic characterization of the non-muscle myosin IIA isoform. Similar to non-muscle myosin IIB, non-muscle myosin IIA shows high ADP affinity and little enhancement of the ADP release rate by actin. The ADP release rate constant, however, is more than an order of magnitude higher than the steady-state ATPase rate. This implies that non-muscle myosin IIA spends only a small fraction of its ATPase cycle time in strongly actin-bound states, which is in contrast to non-muscle myosin IIB. Non-muscle myosin II isoforms thus appear to have distinct enzymatic properties that may be of importance in carrying out their cellular functions.

Actins↗
PubMed2003

Refolding and purification of Apo2l/TRAIL produced as inclusion bodies in high-cell-density cultures of recombinant Escherichia coli.

As a new member of tumor necrosis factor (TNF) superfamily, TNF-related apoptosis-inducing ligand (Apo2L/TRAIL) was produced mainly as inclusion bodies by recombinant Escherichia coli with a temperature-inducible expression system. High concentrations of both biomass (65 g dry cells l(-1)) and inactive TRAIL (4.8 g l(-1)) were obtained by applying a high-cell-density cultivation procedure. After the inclusion bodies were washed and solubilized. TRAIL refolded when at 1 mg ml(-1) by a simple pulse dilution method with a 35% yield. Renatured TRAIL was purified to electrophoretic homogeneity by one-step immobilized metal affinity chromatography. The purified TRAIL showed strong cytotoxicity activity against human pancreatic 1990 tumor cells, with ED50 about 1.6 microg ml(-1).

Apoptosis Regulatory Proteins↗
PubMed2003

Role of Toll-like receptor signaling in the apoptotic response of macrophages to Yersinia infection.

Macrophages encode several Toll-like receptors (TLRs) that recognize bacterial components, such as lipoproteins (TLR2) or lipopolysaccharides (TLR4), and activate multiple signaling pathways. Activation of transcription factor NF-kappaB by TLR2 or TLR4 signaling promotes proinflammatory and cell survival responses. Alternatively, TLR2 or TLR4 signaling can promote apoptosis if the activation of NF-kappaB is blocked. The gram-negative bacterial pathogen Yersinia pseudotuberculosis secretes into macrophages a protease (YopJ) that inhibits the activation of NF-kappaB and promotes apoptosis. We show that primary macrophages expressing constitutively active inhibitor kappaB kinase beta (IKKbeta) are completely resistant to YopJ-dependent apoptosis, indicating that YopJ inhibits signaling upstream of IKKbeta. Apoptosis is reduced two- to threefold in TLR4(-/-) macrophages infected with Y. pseudotuberculosis, while the apoptotic response of TLR2(-/-) macrophages to Y. pseudotuberculosis infection is equivalent to that of wild-type macrophages. Therefore, TLR4 is the primary source of apoptotic signaling in Yersinia-infected macrophages. Our results also show that a small percentage of macrophages can die as a result of an apoptotic process that is YopJ dependent but does not require TLR2 or TLR4 signaling.

3T3 Cells↗
PubMed2003

[Evaluation of glucocorticoid in treatment for patients with acute respiratory distress syndrome].

OBJECTIVE: To value of glucocorticoid (GC) in treatment for patients with acute respiratory distress syndrome (ARDS) was evaluated. METHODS: The clinical data from all patients with ARDS in medical ICU (MICU) during May 2000 to Aug. 2002 were collected. They were divided into two groups, GC and non-GC groups, in order to compare their age, sex, acute physiology and chronic health evaluation II (APACHE II) score, PaO2/FiO2, Qs/Qt, level of positive end-expiratory pressure(PEEP), mortality and dead reason of death, depending on whether GC was given or not. In cases with administration of GC, the dosage, as well as duration of treatment was analyzed in terms of the overcome. RESULTS: There were 77 cases totally, among them 60 cases were of GC group and 17 of non -GC. Their age, sex, APACHE II score, PaO2/FiO2, Qs/Qt, use of artificial ventilation and its duration, level of PEEP, and the extent of relief from hypoxemia showed no significant differences between two groups (P>0.05). Even the mortality for patients who were treated with GC was higher than those without (71.7% vs. 52.9%), though there was no statistically significant difference (P>0.05). The percentage of patients died primarily of ARDS was low in both groups (7.0% and 11.1%). The age, APACHE II score and underlying diseases for non-survivors were older and higher than survivors (P<0.001 or P<0.005) and their duration of staying in ICU was shorter than the latter (P<0.05). The mortality of patients who were given GC before or during 24 hours of the establishment of the diagnosis of ARDS (66.7% and 68.2%) was lower than those who were given GC 24 hours after the diagnosis of ARDS (90.0%). CONCLUSION: GC could be one of effective treatments for ARDS, and it should be given without hesitation when refractory hypoxemia and shock were found.

APACHE↗
PubMed2003

[Construction of human papilloma virus type 18 E6E7 genes in adeno-associated virus expression vector and checking its activity for malignant transformation].

BACKGROUND: To construct human papillomavirus type 18 (HPV18 E6E7) adeno-associated virus (AAV) for studying the role of HPV E6E7 in the development of human cancer. METHODS: HPV18 E6E7 genes were inserted into adeno-associated virus expression vector and then infected 293 cell line. The expression of HPV18 E6E7 genes were confirmed by using RT-PCR/Southern blot assay. RESULTS: There was HPV18 E6E7 genes in the malignantly transformed cell line. The 293TL cells compared with the parent cells transformed cells grew more rapidly, lost their contact inhibition and formed more and large colonies in soft agar. CONCLUSIONS: HPV18 E6E7 AAV was successfully constructed and could induce malignant transformation. HPV18 E6E7 AAV can be use for studying the immortalization and malignant transformation of human normal epithelial cells.

Cell Line↗
PubMed2003

[Observation and comparison on microstructure of immobilized Aerobacillus fusiformis under wastewater treatment].

Aiming at printing ink wastewater, a strain of bacterium was isolated from activated sludge, and identified as Aerobacillus fusiformis. The Aerobacillus fusiformis was respectively immobilized in calcium alginate gel, polyvinyl alcohol (PVA) and microporous ceramics and their microstructure were observed by scanning electron microscope (SEM). It was found that calcium alginate gel might dissolve in the wastewater, and the activity was restricted as cells wrapped in PVA, so the COD removal ratio was low. The method of immobilized cells using microporous ceramics is simple and COD removal efficiency can be achieved. In addition, the immobilized bacterium could not be separated easily from the ceramics in the wastewater.

Alginates↗
PubMed2003

[Survivin antisense RNA enhances taxol-induced apoptosis in leukemia cell line HL-60].

OBJECTIVE: To explore the effects of survivin antisense RNA on taxol-induced apoptosis in leukemia cell line HL-60. METHODS: A survivin antisense eukaryotic vector pcDNA3-SVVas was transferred into HL-60 cells by electroporation. The live fraction was determined by trypan blue dye exclusion assay. Cell counting and MTT assay were performed to evaluate the sensibility of the transfected cells to taxol. Apoptosis was detected by DNA gel electrophoresis and nuclear staining. RESULTS: Two positive cell clones, HL-60 SVVas and HL-60 neo were obtained. Compared to HL-60 and HL-60 neo cells, HL-60 SVVas cells growth was significantly reduced (P < 0.05). By MTT assay, the IC(50) of taxol to HL-60 SVVas, HL-60 neo and HL-60 cells were (14.4 +/- 1.87) ng/ml, (31.9 +/- 6.38) ng/ml and (32.0 +/- 3.52) ng/ml, respectively, the difference was significant by statistic analysis (P < 0.01). Agarose gel electrophoresis of genomic DNA from HL-60 SVVas showed typical DNA ladder, but DNA from HL-60 neo and HL-60 did not. Nuclei become condense in HL-60 SVVas cells. CONCLUSION: Survivin antisense RNA could enhance taxol-induced apoptosis in leukemia cell line HL-60. This may lay an experimental foundation for further research of gene therapy in leukemia.

Antineoplastic Agents, Phytogenic↗
PubMed2003

[Evaluation of glucocorticoid in treatment for patients with acute respiratory distress syndrome as a result of serious community-acquired pneumonia].

OBJECTIVE: To evaluate the usage of glucocorticoid (GC) in treatment for patients with acute respiratory distress syndrome (ARDS) resulting from serious community-acquired pneumonia (SCAP). METHODS: The clinical data from all patients with ARDS resulting from SCAP in medical ICU (MICU) from May 2000 to Feb. 2003 were collected. Their age, sex, acute physiology and chronic health evaluation (APACHE II) score, PaO(2)/FiO(2) and Qs/Qt, the severity of SCAP, mechanical ventilation (MV) and the level of positive end-expiratory pressure (PEEP), time of stay in ICU, improvement of SCAP and oxygenation, as well as mortality and reasons of death were analyzed, respectively. So was did the influence of administration of GC on hypoxemia, septic shock, and their prognosis. RESULTS: There were 24 cases totally, among them 7 patients had not taken GC, and 5 patients were cured (71.4 percent), and the other 2 cases died (28.6 percent) Their direct cause of death were multiple organ dysfunction syndrome (MODS) and ARDS, respectively In 17 cases GC was given because hypoxemia and septic shock could not be alleviated with ordinary therapy, including MV Among them only 5 patients (29.4 percent) were cured, and all others (12 cases, 70.6 percent) died, and the major direct cause of death was MODS (6 cases, 75.0 percent). A few of them died of ARDS and septic shock (1 case, 12.5 percent, respectively). The severity of SCAP, as well as other clinical data of the survivors, showed no significant difference compared with the nonsurvivors (P>0.05). But except for their PaO2/FiO2, Qs/Qt and shock, their pulmonary infection was better controlled than deaths (P<0.001). CONCLUSION: Refractory hypoxemia and septic shock of patients with pulmonary ARDS might be alleviated by GC when they are treated with routine methods, including MV, thus it enabled to win the time for other effective treatments.

APACHE↗
PubMed2003

Natural gas and indoor air pollution: a comparison with coal gas and liquefied petroleum gas.

OBJECTIVE: The study was designed to compare the combustion products of coal gas, liquefied petroleum gas and natural gas in relation to indoor air pollution. METHODS: Regular pollutants including B(a)P were monitored and 1-hydroxy pyrene were tested in urine of the enrolled subjects. Radon concentrations and their changes in four seasons were also monitored in the city natural gas from its source plant and transfer stations to final users. To analyze organic components of coal gas, liquefied petroleum gas and natural gas, a high-flow sampling device specially designed was used to collect their combustion products, and semi-volatile organic compounds contained in the particles were detected by gas chromatograph-mass spectrograph (GC/MS). RESULTS: Findings in the study showed that the regular indoor air pollutants particles and CO were all above the standard in winter when heating facilities were operated in the city, but they were lowest in kitchens using natural gas; furthermore, although NO2 and CO2 were slightly higher in natural gas, B(a)P concentration was lower in this group and 1-hydroxy pyrene was lowest in urine of the subjects exposed to natural gas. Organic compounds were more complicated in coal gas and liquefied petroleum gas than in natural gas. The concentration of radon in natural gas accounted for less than 1% of its effective dose contributing to indoor air pollution in Beijing households. CONCLUSION: Compared to traditional fuels, gases are deemed as clean ones, and natural gas is shown to be cleaner than the other two gases.

Air Pollution, Indoor↗
PubMed2003

[Structure and heterogeneity of urban vegetation landscape in Shenyang].

Studies on the structure and heterogeneity of urban vegetation landscape in Shenyang city showed that the most vegetation patches were in the street corner, accounted for more than 50% of the total vegetation patch, and their area was only 4.45% of the total vegetation area. In terms of the size of the patches, the average area of shelter vegetation and park vegetation was 66.97 hm2 and 59.31 hm2, respectively, while that of street corner vegetation and garden vegetation was 0.71 hm2 and 0.38 hm2, respectively. Street corner vegetation had the highest index of landscape diversity, while park vegetation had the lowest one. In the seven districts of Shenyang city, all types of vegetation had a small landscape dominance and evenness, but patch vegetation had a more than 10 times of landscape dominance than corridor vegetation, indicating that there was somewhat imbalance in the allocation of different vegetation patch types. It's suggested that the quantity of patch vegetation should be increased, and the public vegetation should be distributed evenly. Increasing vegetation corridor is also important because it can link the downtown area to the suburb natural vegetation ecosystems. For example, the South Canal Belt Park of Shenyang is a good vegetation corridor, which can beautify Shenyang city, discharge sewage, drain flood, and improve microclimate.

Agriculture↗
PubMed2003

[Quantitative analysis of urban forest structure: a case study on Shenyang arboretum].

The spatial features and attribute data of urban forests in Shenyang arboretum were acquired by using aerial photographs and field investigation. After systemic and quantitative analysis of the species composition and spatial distribution pattern of urban forest community based on geographic information system (GIS), the following results were achieved: 1) the vegetation in the arboretum was rich and in a good condition. Phellodendron amurense, Robinia pseudoacacia, and Ulmus punita were the main species according to their abundant individuals and relative dominance. The spatial distribution pattern of this vegetation indicated that it was in a growing level and in the best state for ecological benefits; 2) the tree species relative dominance based on vegetation quantity had no distinct relationship with the species abundance, and the species having abundant individuals might have a low relative dominance; and 3) the curve displayed in the relationship diagram between tree individuals and tree height showed ascending and protruding. With the increment of tree height class, the individuals were unchanged nearly at the beginning, but when the height was more than 12 m, the individuals reduced distinctly, and the curve displayed a quickly declined trend. The relationship between tree individuals and tree diameter at the breast height (DBH) showed the same result.

City Planning↗
PubMed2003

[Flora and vegetation types in the downtown area of Shenyang].

Shenyang city is located in the intersect zone among Changbai, Mongolia and North China flora, which has a plenty of plant species belonging to 98 families, 371 genera and 779 species. There are 85 plant species in the largest family Companulaceae, and more than 20 species in the families Cyperaceae, Rosaceae, Leguminoseae, Polygonuceae, Labiatae, Lilaceae and Ranunculaceae. These families have 384 species in total, and 49.3% of them are found in Shenyang city. The flora had 23 geographical components types, and 89.3% of them were of the temperate type. Based on the epigenesis and functions of vegetation and the role of the dominant species, the urban vegetation in the downtown area of Shenyang was divided into 3 vegetation classes, 14 vegetation groups and 57 vegetation types, and the components, structure, dynamics and functions of 3 representative vegetation classes were analysised.

China↗
PubMed2003

[Dust absorption effect of urban conifers in northeast China].

Dust pollution is much heavier in winter than in other seasons in the cities of Northeast China, because the urban heating system consumes mainly coal as energy resources. Deciduous trees can hardly absorb dust because of their defoliation, and hence, urban conifer trees become more important in dust absorption in winter. This paper studied the dust absorption ability of 7 conifers under the same and different dust pollution status in Shenyang city, Northeast China. The results showed that the dust absorption ability of conifers was decreased in the order of Abies holophilla > Picea mongolica > P. koraiensis > Taxus cupidata > Pinus bungeana > P. armandi > P. tabulaeformis. Different conifers had different surface structures. Pinus bungeana, P. armandi and P. tabulaeformis had smooth surfaces, their cells and stomata arranged in order, and hence, their dust absorption ability was poor. P. koraiensis, Abies holophilla and Taxus cupidata had coarse surfaces, and their cells and stomata arranged out of order. There were even many tubercular things on the surface of P. koraiensis, and hence, their dust absorption ability was stronger. The dust absorption ability of conifers was related the shape of their leaf sections. The upper leaf surface of Pinus bungeana and P. tabulaeformis was arc, not opted to absorb the dust. The leaf section of P. armandi was prism, and its upper surface was narrow, and hence, its dust absorption ability was also poor. The leaves of Picea mongolica and P. koraiensis had four edges, their upper surfaces were broader and flatter than the former three species, and hence, they had stronger dust absorption ability. The leaf section's shape of Abies holophilla and Taxus cupidata was also broad and flat, which made the dust absorption ability of the two latter's was stronger than other three Pinus species and two Picea species.

Absorption↗
PubMed2003

[The effect of CTLA4Ig-modified dendritic cells on proliferation and cytotoxicity of lymphocytes in-vitro].

AIM: To study the effect of dendritic cells (DCs) modified by CTLA4Ig on T-cell proliferation and the cytotoxic T lymphocyte killer activity. METHODS: The expressing vector pG/CTLA4Ig was transfected into DCs via lipofectamine reagent mediation. CTLA4Ig fusion protein secreted by DCs in the culture supernatant was confirmed by sandwich ELISA and SDS-PAGE. Peripheral blood mononuclear cells (PBMC) from C57BL/6 mice (as reaction cells) and DCs modified or unmodified by CTLA4Ig (as stimulation cells) were co-cultured for 6 days. MTT colorimetry was used to detect lymphocyte proliferation. Lactate dehydrogenase release method and sandwich ELISA assay was used to examine the cytotoxic activity and T-cell apoptosis. RESULTS: CTLA4Ig fusion protein and DCs modified by CTLA4Ig could significantly inhibit lymphocyte proliferation response and cytotoxic activity of specific cytotoxic T lymphocytes, and induce T-cell apoptosis, while unmodified-DCs could markedly induce lymphocyte proliferation response. CONCLUSION: The DCs of stably expressing CTLA4Ig fusion protein could not only markedly inhibit T-cell proliferation and cytotoxic activity of CTL, but also induce T-cell apoptosis.

Abatacept↗
PubMed2003

[Cloning and sequencing of Sry gene of muntiacus].

Using the primers from SRY gene--HMG Box for PCR amplification in genomic DNA of Muntiacus reevesi cell strains, a 220bp fragment was obtained in the male but not in the female. The 220bp fragment was cloned into the pGEM-T vector using T/A clone method. The identified positive clone was sequenced. The result shows that 82.6% nucleotides(152bp/184bp) are homologous between Muntiacus Sry and human SRY gene. It suggests that SRY is highly conserved during evolution.

English Abstract↗
PubMed2002

[Regulation of lipopolysaccharide-induced inducible nitric oxide synthase gene expression by protein kinase C].

OBJECTIVE: To explore the molecular mechanism of inducible nitric oxide synthase (iNOS) gene expression induced by lipopolysaccharide (LPS) in monocytes or macrophages. METHODS: Luciferase report gene vector pGL2iNOSLuc driven by murine iNOS promoter region was constructed using gene recombination technique. RAW264.7 cells were cultured and transfected with luciferase report gene vector pGL2iNOSLuc. Twenty four hours later, PKC inhibitor H-7, calcium channel blocker verapamil, was added into the culture. LPS or PKC activator PMA was added 2 hours later to stimulate the cells. The activity of beta-galactosidase and luciferase was examined and the relative luciferase activity, representing the iNOS transactivity, was calculated. Modified Griess method was used to measure the concentration of NO(2)(-)/NO(3)(-) in the culture so as to evaluate the effect of PKC inhibitor on NO production induced by LPS. RT-PCR was used to study the effect of LPS on iNOS gene expression in RAW264.7 cells. RESULTS: Thirty minutes after stimulation of RAW264.7 cells by LPS, the activity of PKC in cytomembrane increased and the activity of PKC in cytoplasm decreased significantly in comparison with the baseline levels (P < 0.01). The NO concentration was 30.1 micro mol/L +/- 5.4 micro mol/L 12 hours after the stimulation of LPS on RAW264.7 cells, and was much more higher 24 and 48 hours after, all significantly higher than before (all P < 0.01). The NO concentration in the supernatant with H-7 at any time point was significantly lower than those in corresponding samples without H-7 (all P < 0.01). After stimulation of LPS and PMA, the relative luciferase activity was 25.3 +/- 4.6, significantly higher than the baseline level (P < 0.01). H-7 and verapamil significantly inhibited the LPS-induced iNOS transactivity (both P < 0.01). iNOS mRNA expression was increased greatly, and H-7 significantly inhibited this expression 12, 24, and 48 hours after LPS stimulation. CONCLUSION: In RAW264.7 cells, LPS stimulation increases intracellular calcium and activates PKC, thus inducing iNOS gene expression that contributes to the production of NO, which is an important signaling mechanism of NO production in septic shock.

1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine↗