Search PubMed⌕ Search

Biomedical subjects

Jun Zhang

Publications and source records attributed to Jun Zhang.

At least 325 records · Page 18Linked to original sources
PubMed2004

[Clinical study on the early nutrition support in postoperative patients with critical hypertensive intracerebral hemorrhage].

OBJECTIVE: To investigate the clinical significance of early nutritional support for patients with critical hypertensive intracerebral hemorrhage (HICH) in a critical condition after operation, and the rationale of different methods of nutritional support. METHODS: One hundred and seven HICH patients after operation with Glasgow coma score (GCS) 6-8 were randomly divided into three groups: early enteral nutrition (EEN) group (38 cases); early parenteral nutrition (EPN) group (35 cases), conventional treatment controls (34 cases). They were given different nutritional supports 48 hours after operation. Changes in nutritional parameters and the clinical complications in three groups after treatment were observed, and the treatment effects after 3 months were compared. RESULTS: At the end of first week after operation, nutrition parameters including albumin (ALb), hemoglobin (Hgb) in EEN and EPN groups were better than those in control group(P<0.05); at the end of second week, they were differences among three groups but without statistical significance (P>0.05). The complications were higher in EPN and control groups (P<0.05 or P<0.01). The outcome was assessed 3 months after the operation in term of activity of daily life (ADL), and the result was better in EEN group than that in EPN and control groups (P<0.005). CONCLUSION: Postoperative HICH patients in critical condition could be benefited with EEN, and complications could be reduced with improved prognosis.

Adult↗
PubMed2004

[Construction and expression of single-chain antibody of neutralizing monoclonal antibody 13D8 against hepatitis E virus].

AIM: To weaken the immunogenicity of the neutralizing monoclonal antibody (mAb) 13D8 against hepatitis E virus and express its scFv. METHODS: The V(L) and V(H) genes were cloned by RT-PCR from hybridoma cells producing mouse mAb. And then V(H)-linker-V(L) fragment (scFv) was constructed and cloned into vector pTO-T7. The scFv protein was expressed in E.coli. The activity of expressed scFv was detected by ELISA and Western blot. RESULTS: SDS-PAGE analysis showed that the scFv was highly expressed mostly in the form of inclusion body in E.coli, and the yield was up to 26.8% of the total bacteria protein. The results of indirect ELISA and Western blot showed that the expressed scFv could bind specifically to a recombinant protein in OFR2 region of HEV (NE2). The result of competitive ELISA demonstrated that the epitope recognized by the scFv was the same as that by mAb 13D8. CONCLUSION: The scFv constructed from V(H) and V(L) genes of mAb 13D8 with immunological activity was successfully expressed.

Amino Acid Sequence↗
PubMed2004

[Isolation of genomic DNA from Cinnamomum cassia Presl].

OBJECTIVE: To extract high-quality DNA for RAPD and other molecular biology research from Chinese traditional medicine Cinnamomum cassia Presl.. METHOD: Improved CTAB method, low pH medium with high salt method (LPHS) and urea method were used for DNA extract. The yield and quality of DNA was analysed by electrophoresis, ratios of A260/A280 and PCR amplification. RESULTS: The modified CTAB method and low pH medium with high salt method can produce high qualiy DNA for PCR amplification.

Cetrimonium Compounds↗
PubMed2004

Membrane receptor mapping: the membrane topography of Fc(epsilon)RI signaling.

Ligand binding to membrane receptors initiates cascades of biochemical events leading to physiological responses. Hundreds of proteins and lipids are implicated in signaling networks and programs in genomics and proteomics are continuously adding new components to the signaling "parts lists". Here, we generate high resolution maps of signaling networks using cytoplasmic face-up membrane sheets that can be labeled with immunogold probes (3-10 nm) and imaged in the transmission electron microscope. Our model system is the mast cell and we focus on mapping the topography of the high affinity IgE receptor, Fc(epsilon)RI, its associated tyrosine kinases, Lyn and Syk, and the signaling proteins that propagate signals from these kinases. Crosslinked receptors and their signaling partners segregate during signaling to multiple, dynamic membrane domains, including a transient Fc(epsilon)RI-Lyn domain and at least two other distinct domains, one characterized by the presence of receptor, Syk and multiple signaling proteins, but not Lyn (primary signaling domains), and one characterized by the presence of LAT and PLCgamma1 but not receptor (secondary signaling domains). PI 3-kinase associates with both primary and secondary signaling domains and may help to recruit specific signaling proteins through the local remodeling of inositol phospholipids. The lipid raft markers, GM1 and Thy-1, fail to localize in native membrane sheets either with each other or with signaling domains. We introduce new probes to localize multiple signaling molecules on the same membrane sheet and new computational tools to capture and analyze their topographical relationships. In the future, we expect that high resolution maps of signaling networks will be integrated with chemical kinetic analyses, with cell fractionation data and with a range of real-time fluorescence measurements, into mathematical models with power to predict mechanisms that regulate the efficiency, specificity, amplitude and duration of signaling pathways.

Animals↗
PubMed2004

[Interspecific interaction between Moina mongolica and Brachionus plicatilis].

In a laboratory experiment, Moina mongolica and Brachionus plicatilis were polycultured at four relatively inoculating densities, i.e., 0.06/0.30, 0.10/0.30, 0.30/0.30 and 0.60/0.30 (ind x ml(-1)/ind x ml(-1)), while M. mongolica monocultured at 0.06, 0.10, 0.30 and 0.60 ind x ml(-1) and B. plicatilis at 0.30 ind x ml(-1) were used as the control. Interspecific interference did exist between M. mongolica and B. plicatilis when these two species coexisted in a microcosm. In the polycultured microcosms, depressed population density of M. mongolica resulted from the coexistence of B. plicatilis, and M. mongolica maintained at extremely low density. In opposite, M. mongolica had negligibly negative influence on the population of B. plicatilis. Further experiment showed that the mortality of M. mongolica deprived of food for 120 h was 100%, while 90% of B. plicatilis survived after 144 h of food deprivation. The relatively strong capacity of B. plicatilis in tolerating starvation may be one of the important reasons for it wins the competition against M. mongolica.

Animals↗
PubMed2004

[The discrepancy between ICP and MCP caused by orthodontic treatment and its quantitative assessment to the effect of later orthodontic treatment.].

PURPOSE: To investigate the discrepancy between ICP and MCP caused by orthodontic treatment. to evaluate the treatment effect of the malocclusion with later orthodontic treatment. METHODS: Nineteen cases were selected and treated with preadjusted appliance and combination headgear appliance.Pre- and post- treatment celphalometric radiographs were analyzed. RESULTS: Discrepancy between ICP and MCP may be resulted from improper design and operation of orthodontists and poor cooperation of patients; By preadjusted appliance and combination headgear appliance,upper dental arch was moved distally; Molar relationship was changed into Class I by bodily movement; A harmonization between ICP and MCP was rehabilitated. CONCLUSIONS: The discrepancy between ICP and MCP should be minded; Preadjusted appliance and combination headgear appliance were effective in the correction of the discrepancy between ICP and MCP.

Cerebellum↗
PubMed2004

[Correlation between sensitivity to TRAIL and expression level of DR5 on surface of tumor cells].

OBJECTIVE: To investigate the correlation between sensitivity to tumor necrosis factor-related apoptosis inducing ligand (TRAIL) and expression level of death receptor 5 (DR5) on tumor cell surface. METHODS: Anti-DR5 mAb was used to detect expression level of DR5 on surface of tumor cells by flow cytometry. Sensitivity to apoptosis induced by TRAIL was determined by TRAIL apoptosis kit. The correlation between expression level of DR5 and sensitivity to TRAIL was analyzed. RESULTS: The expression of DR5 on surface of tumor cells was approximately 97.9% in U937 cells, 95.1% in Jurkat cells, 93.8% in SW480 cells, 86.2% in HCT116 cells, 64.2% in HL-60 cells, 46.6% in HeLa cells and 13.1% in K562 cells, respectively. The apoptosis rate induced by TRAIL was 72.6% in U937 cells, 85.2% in Jurkat cells, 78.6% in SW480 cells, 70.2% in HCT116 cells, 60.1% in HL-60 cells, 45.4% in HeLa cells and 12.3% in K562 cells, respectively. There was a significant positive correlation between the expression level of DR5 with TRAIL-inducing apoptosis (r = 0.997, P < 0.001). CONCLUSION: TRAIL-inducing apoptosis is related to the expression level of DR5 on surface of tumor cells. The results confirm the importance of DR5 expression for induction of apoptosis by TRAIL.

Antibodies, Monoclonal↗
PubMed2004

[Extracorporeal membrane oxygenation treatment with high-volume hemofiltration in patients with multiple organ dysfunction syndrome].

OBJECTIVE: To evaluate whether extracorporeal membrane oxygenation (ECMO) with high-volume hemofiltration (HVHF) improves hypoxemia and renal function in patients with multiple organ dysfunction syndrome (MODS). METHODS: The study was executed in 8 MODS patients with acute respiratory distress syndrome (ARDS) and acute renal failure (ARF). They were randomly assigned to either 8 hours of HVHF combined with ECMO or HVHF alone in random order. The changes in arterial oxygen pressure(PO(2)), pulse oxygen saturation (SpO(2)), arterial carbon dioxide pressure (PCO(2)), serum creatinine (SCr) and blood urea nitrogen (BUN) levels were measured. RESULTS: Compared with that of before the treatment, PO(2) was increased significantly at 1, 4, 8 hours, and SpO(2) was increased significantly at 4, 8 hours after ECMO with HVHF in MODS patients, the changes of PO(2), SpO(2)and PCO(2)were not significantly during HVHF (all P>0.05). The average concentrations of BUN and SCr were decreased significantly after HVHF or HVHF with ECMO therapy in MODS patients. CONCLUSION: HVHF with ECMO, which can improve hypoxemia significantly, may be a better option for the treatment of MODS patients.

Adult↗
PubMed2004

[Relationship between serum leptin and tumor necrosis factor and endothelin in patients with chronic renal failure].

OBJECTIVE: To assess the serum level of leptin and its relationship between tumor necrosis factor, and endothelin in patients with chronic renal failure. METHODS: Serum level of leptin,tumor necrosis factor and endothelin were measured in 40 patients with chronic renal failure and 20 healthy controls by radioimmunoassay. Correlation analysis was performed between serum level of leptin and tumor necrosis factor and endothelin. RESULTS: Serum leptin in patients with chronic renal failure was significantly higher than that in healthy control subjects((19.25+/-4.89)microg/L vs. (5.57+/-1.69)microg/L, P<0.01). There was significant positive correlation between serum leptin and tumor necrosis factor and endothelin (r(TNF)=0.829, r(ET)=0.605; both P<0.01). CONCLUSION: The abnormal increased serum levels of tumor necrosis factor and endothelin are associated with hyperleptinemia in patients with chronic renal failure.

Adult↗
PubMed2004

[The PLS analysis with short wave near-infrared of whole wheat for protein].

Short wave near-infrared spectrum of whole wheat was obtained by diffusion reflection. PLS method was used to analyze protein content of whole wheat. Different wavelength ranges were chosen for regression and information abstraction. The 3D curves were shown for different factors, prediction residual sum of squares (PRESS), and RMSECV. The best wavelength ranges and factors were determined. Analysis results for protein content of whole wheat were shown in three wavelength regions, and the predicted results were compared and discussed. The method of selecting advantageous wavelength ranges is feasible to obtain high prediction precision.

Plant Proteins↗
PubMed2004

[Optimized-design of spectral discriminator for infrared spectra of polluted gases].

According to the spectral features of polluted-gases infrared spectra, a mixed multi-branch spectral discriminator is proposed. Experimental results indicate that the spectral discriminator not only has simple structure and high veracity for classification and recognition, but also has remarkable flexibility and stability. So it is a high-efficiency discriminator for real-time identified infrared spectra of polluted gases.

English Abstract↗
PubMed2004

[Research on model and wavelength selection of near infrared spectral information].

Based on stepwise linear regression, and according to the theory of near infrared absorbption, spectrum (1000-2500 nm) obtained by detector was divided into three ranges, which were I (1000-1400 nm) and II (1400-1860 nm) and III (1860-2500 nm). In each range the regression wavelengths of different wavelength gaps were picked up stepwise. Regression coefficients and parameters were calculated by Matlab5.3 Program. Regression models were built up in different ranges with different wavelength gaps. Best models could be determined. Prediction results of protein content of ground wheat were displayed in scatter plots. Different results were discussed and compared, which has referencemeaning for application.

Linear Models↗
PubMed2004

[The research to the optimal calibration model for discrete scanning spectrometers].

For spectrometers which don't operate in consistently scanning mode such as fixed-filter spectrometer, diode arrays spectrometer and so on, how to find an optimal wavelengths combination rapidly and accurately has always been a key problem in NIR so far. The conventional methods to choose the optimal wavelengths for calibration are Forward Stepwise multiple linear Regression (FSR) and Backward Stepwise Regression (BSR), which choose the optimal wavelengths based on the t test result of all the calibration wavelengths. However, maybe the wavelength eliminated is very useful in application and the wavelength chosen may not be so useful as expected, as a result it is compulsory to make more tests to verify the truly applicable wavelength combination for calibration. In this paper the combination of the combination-making algorithm in combinatorics and computer languages which operate facing matrix is used to choose the optimal combination of wavelengths for calibration automatically and efficiently by computer. The most robust calibration equation can be obtained by making analysis of calibration regression that operates to find the minimum root mean standard error of calibration.

Calibration↗
PubMed2004

[The algorithm of eliminating the similar samples in the process of calibration and prediction].

During the manufacture and debugging of the NIR instruments it is compulsory to make final calibration analysis to verify whether the instruments operate correctly. However, the conventional method of NIR calibration needs to make calibration analysis for the instruments with all the samples at hand. In fact in order to cover the samples that will be encountered in the future the amount of the samples set and the labor that the personnel need to offer are enormous. In this paper a new algorithm is presented which can be used to effectively eliminate the similar samples in the original sample set. By using this algorithm we have chosen 94 optimal samples in the original 178 sample set successfully. After performing calibration experiment we found that the sample set chosen by this algorithm are equally representative to the original sample set and obtained almost the same precision compared to the original sample set when the two sample sets were individually calibrated. This algorithm brings great relief to the labor of the workers, presents the possibility of performing more experiments and greatly improves the efficiency of performing calibration experiment. As a result, the amount of calibration sets and the labor of the personnel are reduced remarkably.

Algorithms↗
PubMed2004

[Influence of smooth, 1st derivative and baseline correction on the near-infrared spectrum analysis with PLS].

This paper studied the influence of using pre-procession such as smooth, 1st derivative and baseline correction on the analysis of near-infrared spectrum. Comparing the analysis results by the pre-procession methods, and using PLS arithmetic, the best pre-procession was determined. In smooth pre-procession method, the best smooth points were proposed for regression using PLS. The analysis result is satisfactory.

English Abstract↗
PubMed2004

[Particulate recombinant hepatitis E virus capsid protein and its antigenicity and immunogenicity].

An E. coli expressed recombinant antigen NE2 was reported to aggregate into homo-oligomer, and can induce protective antibodies on rhesus monkey, but its immunogenicty was much weak after being purified. In this study, three N-terminal extension mutant of NE2 were expressed in E. coli, one of which named HEV 239 was found to aggregate into particle. HEV 239 antigen had good reactivity with sera of hepatitis E patients. The reactivity of HEV 239 against neutralization monoclonal antibody 8C11 was similar as NE2 antigen, while the reactivity of it against another neutralization monoclonal antibody 8H3 is much better than NE2 antigen, which indicated better antigenicity of HEV 239 than NE2. The diameter of purified HEV 239 particulate antigen was between 15 nm to 30 nm. The ED50 of immunization of HEV 239 particle adsorbed by aluminum adjuvant to BALB/c mice was between 0.08 microg to 0.25 microg. In contrast, the seraconversion rate of mice immunized by NE2 antigen adsorbed by aluminium adjuvant was only 25% on 60 microg vaccination. These results suggested that HEV 239 antigen particle has better immunogenicity as well as antigenicity than those of NE2 antigen, so it is a better vaccine candidate against HEV.

Animals↗
PubMed2004

[Hepatitis E virus capsid protein production by high cell density culture of recombinant Escherichia coli].

Production of Hepatitis E Virus capsid protein by high cell density culture in recombinant E. coli has been studied in 10L and 30L fermentors. The effects of different factors on growth and producing recombinant protein of E. coli have been studied by batch culture, such as different media, the ratio of phosphate and Magnesium sulfate. Comparison of fermentation performance for recombinant E. coli in different fed-methods culture has been investigated by fed-batch culture. The effects of inducing at different stages of growth and time of inducing on growth and producing recombinant protein, also obtained by fed-batch culture. At last, the solubility of inclusion body in different urea concentrations also has been obtained by fed-batch culture. The results show that the concentration of phosphate and Magnesium sulfate in the optimal media is 80mmol/L and 20mmol/L in batch culture respectively, that induction with 1.0mmol/L IPTG at mid log phase (about 45 OD at 600nm) is suitable for growth and recombinant protein expression, the cells were approaching stationary growth phase and the maximum cell OD at 600nm of 80 was achieved in 5h of fed-batch culture, and the expression level is 29.74%. The results also indicate that the solubility of inclusion body in 4mol/L urea solution induced at 37 degrees C reaches 14mg/mL, over 80% inclusion body was resolved. The culture process achieved in 10L fermentor could be successfully scaled up to 30L fenmentor with good reproducibility.

Bioreactors↗