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Biomedical subjects

Xi Zhang

Publications and source records attributed to Xi Zhang.

At least 55 records · Page 3Linked to original sources
PubMed2005

[Observation of the therapeutic effect of qianlie sanyu capsule on benign prostatic hyperplasia].

OBJECTIVE: To observe the clinical efficacy of Qianlie Sanyu Capsule on benign prostatic hyperplasia (BPH). METHODS: Seventy-two patients with BPH were randomly divided into a treatment group (40 patients) and a control group (32 patients), the former treated by Qianlie Sanyu Capsule and the latter by Longbishu. Observation were made on the changes of the patients' urination' symptoms, living quality, prostatic volume, Qmax uroflowmetry and excel urine before and after treatment. RESULTS: The total efficacy rates were 92.5% in the treatment group, and 72.5% in the control group. Comparison between the two groups showed significant difference (P < 0.01). The urination symptoms, living quality, Qmax uroflowmetry and the excel urine were better improved in the Qianlie Sanyu group than in the Longbishu. There were significant differences between the two groups (P < 0.05), but none in reducing effect on the prostatic volume. CONCLUSION: Qianlie Sanyu Capsule is an effective drug for BPH.

Capsules↗
PubMed2005

[Observation on the biological behavior of human umbilical cord blood adherent cells].

To study the possibility of separation and culture of human umbilical cord blood adherent cell (HUCBAC), the umbilical cord blood CD34(+) cells were cultured in Dexter system in order to evaluate and observe the biological behavior of adherent cells in vitro. The results showed that all cells were cultured with Dexter system. By day 9-14 (at a median of 11.2 days), adherent cell colonies formed and reached their maximum at 15-22 days (mean 19.6 days), by day 28, all adherent cells spread over the bottom of Petri dish. By means of light microscopy, these cells were found to differentiate into three kinds of cells in culture of 28 days: fibroblast-liked cell, macrophage liked cell and small-round cells. The ratio of these three kinds of cells was 56.8%, 38%, 5.5% respectively. Cytochemistry assay revealed that the positive rate reached 100% in NSE stain and PAS stain; the adherent cell by ALP stain were shown 35% positive, but in POX stain the result was negative. Immunohistochemistry stain revealed that the positive rate of cord adherent cells for CD106, CD29, CD44, CD45, CD50, Fn, Ln, collagen IV etc reached 96%, 93%, 98%, 68%, 72%, 92%, 74%, 83% respectively. It is concluded there are hematopoietic adherent precursors in cord blood CD34(+) cells and the HUCBAC shows some biological behavior of hematopoietic stromal cells.

Antigens, CD34↗
PubMed2005

[Prevalence study of age-related macular degeneration in Caojiadu blocks, Shanghai].

OBJECTIVE: To investigate the prevalence of age-related maculopathy (AMD) in Shanghai residents older than 50 years. METHODS: 1023 individuals were examined in the years 2002 and 2003 for clinical and subjective signs of dry and exudative AMD. A interview concerning clinical symptoms of AMD as also a complete eye exam was performed. Non-mydriatic retinoscopy was done by use of a direct opthalmoscopy. Fundus photography was used to confirm and document the diagnosis. The diagnosis of both forms of AMD was made according to the criteria of the Sub-society of Fundus Disease, Chinese Ophthalmological Society. RESULTS: 15.5% of the included population had AMD and 19 of them were exudative AMD. The prevalences of AMD in the age groups of 50-59, 60-69, 70-79 and more than 80 were identified as 5.7%, 13.5%, 20.2% and 23.5%, respectively (chi(2) = 27.97, P < 0.01). No statistical differences were found concerning atrophic and exudative AMD related to gender, education, daily focus time, smoking, alcohol consumption and systematic diseases. In the AMD patients, 5.1% and 36.2% of the eyes were identified as blind or with low vision. In exudative AMD patients, 23.3% and 63.3% of the eyes were identified as blind or with low vision. The visual acuity of eyes with exudative AMD was significantly lower than the visual acuity of atrophic AMD eyes. (chi(2) = 15.4, P < 0.01). CONCLUSIONS: The prevalence of AMD is high, and increasing with aging. The AMD, especially the exudative AMD, leads to severe visual impairment.

Age Factors↗
PubMed2005

[Development and evaluation of psychometric tests of the Chinese-version of low vision quality of life questionnaire].

OBJECTIVE: To develop and evaluate a Chinese language vision health related quality-of-life (VRQoL) questionnaire. METHODS: The low vision quality of life questionnaire (LVQOL) was translated and adapted into the Chinese-version low vision quality of life questionnaire (CLVQOL). The systematic protocols were set as 3 forward translations, 2 committee reviews and 1 back-ward translation. The CLVQOL was performed in 100 randomly selected people with low vision (primary group) and 100 people with normal vision (control group). Ninety-four participants from the primary group completed the CLVQOL and repeated 2 weeks later (test-retest group). The results were compared with patient demographics and the internal consistency reliability, test-retest reliability, item-internal consistency, item-discrimination validity, construct validity and discrimination validity of the CLVQOL were calculated. RESULTS: The review committee agreed that the CLVQOL replicated the meaning of the LVQOL and was sensitive to cultural adaptations. The Cronbach alpha coefficient and the split-half coefficient for the four scales and total CLVQOL scales were 0.75 to 0.97. The test-retest reliability as estimated by intraclass correlation coefficient was 0.69 to 0.95. Item-internal consistency was > 0.4 and item-discrimination validity was generally < 0.40. The varimax rotation factor analysis of the CLVQOL identified four principal factors. All of the scores of four subscales and the total score of CLVQOL of the primary group were lower than those of the control group, both in patients and local residents. CLVQOL scores were highly correlated with visual acuity. CONCLUSIONS: The CLVQOL is a culturally specific VRQOL measure instrument. CLVQOL can satisfy conventional psychometric criteria, can discriminate visually healthy populations from low vision patients and is valuable in the clinical practice and in the screening of the community populations.

Adult↗
PubMed2005

[Expression of Fas antigen and ligand, placental growth factor in placenta of pregnant women with pre-eclampsia].

OBJECTIVE: To investigate the expression of Fas antigen (Fas) and ligand (FasL), placental growth factor (PlGF) in placenta of pregnant women with pre-eclampsia. METHODS: Expressions of Fas, FasL and PlGF of placenta were determined by immunohistological streptavidin-peroxidase-biotin (SP) method and compared between normal late pregnancy (24 cases) and mild pre-eclampsia (24 cases) and severe pre-eclampsia (24 cases) groups. RESULTS: Different expression of levels Fas, FasL and PlGF were observed in the trophoblasts of most placentae. Positive immunostain of Fas, FasL and PlGF was mainly located in the cytoplasm and membrane of syncytiotrophoblast. FasL and PlGF expressions (63 +/- 4, 81 +/- 6 and 42 +/- 6, 65 +/- 6) were significantly less (P < 0.01), and Fas expression (51 +/- 4, 67 +/- 6) significantly greater in the study subjects compared with controls (P < 0.01). CONCLUSION: Altered expression of Fas and FasL in trophoblasts of placenta may influence pathogenesis or sequelate of pre-eclampsia.

Adult↗
PubMed2005

[The establishment of the two dimensional gel electrophoresis (2-DE) map of hypertrophic scar epidermal cells and the display of the differentially expressed proteins].

OBJECTIVE: To establish and optimize the two dimensional gel electrophoresis (2-DE) map of epidermal cells separated from the hypertrophic scar tissues so as to explore the function of the non cultured epidermal cells during the course of the formation of hypertrophic scar. METHODS: To separate the epidermal cells from the scar tissues, the scar epidermis was digested with Dispase II and trypsin. The total protein of the cells was then extracted and separated with 2-DE and visualized with silver stain. Spots detection and matching were performed with Melaine 3.0 gels analyzing software. The results were then compared with the normal epidermal cells' 2-DE map coming from the Danish Center for Human Genome Research' s 2-DE PAGE Databases. RESULTS: Nearly more than 600 protein spots were identified in the final optimized 2-DE map. We found out 24 differentially expressed proteins by comparing the difference in composition, shape or density of all the spots. In the 24 proteins, there are 8 up-regulated ones, 9 down-regulated ones, 4 disappeared ones and 3 newly founded ones. CONCLUSIONS: The method of digesting the epidermis with Dispase II and trypsin to separate the epidermal cells to establish the 2-DE map is feasible and it made the further study on hypertrophic scar proteomics possible. The 24 differentially expressed proteins revealed that epidermal cells might play a role in the formation of hypertrophic scar.

Cell Line↗
PubMed2005

Detection of clusters of Salmonella in animals in Ontario from 1991 to 2001.

The temporal patterns of Salmonella serovars isolated from animals in Ontario by 2 major laboratories between 1991 and 2001 were identified. Overall, the number of isolates remained relatively stable and the more frequent isolates were dominant, as in earlier surveys. However, the temporal patterns of specific isolates and the serovars isolated differed depending on the laboratory, species of animal, and reason for obtaining the culture (monitoring versus diagnostic sample). A number of temporal clusters were identified, but their dates of occurrence differed by laboratory. Whereas the laboratories serve an essential role for diagnosis and monitoring, the summary information should be interpreted cautiously. The importance of additional information, such as demographic source, specimen type, and appropriate denominator, when interpreting the data is discussed.

Animals↗
PubMed2005

[Experiment of augmenting the survival areas of ischemic flap by transplanting endothelial progenitor cells].

OBJECTIVE: To investigate the feasibility of transplanted endothelial progenitor cells to ischemic flap with increased neovascularization and augmented the survival areas. METHODS: EPCs were isolated from human cord blood, cultured in vitro, identified by immunohistochemistry. Then EPCs were transplanted to ischemic flaps of 9 nude mice's back (experimental group), and 9 nude mice's back flaps was injected with M199(control group). And pedicle division time was 4 days after operation. CM-DiI was used to trace the transplanted cells. The blood perfusion of flaps was monitored by the laser Doppler flowetry, and the capillary density of flaps was detected by CD34 immunohistochemistry. RESULTS: EPCs expressed cell markers CD34, KDR and CD133. Transplanted EPCs survived and was incorporated into the capillary networks in the ischemic flaps of nude mice. The percent of experimental group's flap survival area was (60.3 +/- 2.1)%, significantly higher than the control group[ (34.2 +/- 1.8)%, P < 0.05 ]. The blood perfusion, capillary density of flaps of experimental group was significantly higher than the control group (P < 0.05). CONCLUSIONS: EPCs from human cord blood can increase ischemic flaps neovascularization and augment the survival areas.

Animals↗
PubMed2005

[Quick optimization of high performance liquid chromatographic conditions for separation of flavones of Astragalus].

An analytical method for flavones of Astragalus has been developed and a process of high performance liquid chromatographic (HPLC) condition optimization has been elaborated. The LC retention parameters of 34 components were obtained quickly by using three linear gradient elutions. Overlapping separation range map (OSRM), which is related to the separation quality and the analysis time, was utilized to search the optimised stepwise gradient method for HPLC analysis of flavones of Astragalus. Finally, the optimised stepwise gradient elution conditions were set up with the help of this map. Under the optimised conditions, the sample of flavones of Astragalus was well separated in reasonable time. The method is more convenient than that using a series of isocratic elutions.

Astragalus Plant↗
PubMed2004

Immortalization of human bronchial epithelial cells in the absence of viral oncoproteins.

By expressing two genes (hTERT and Cdk4), we have developed a method to reproducibly generate continuously replicating human bronchial epithelial cell (HBEC) lines that provide a novel resource to study the molecular pathogenesis of lung cancer and the differentiation of bronchial epithelial cells. Twelve human bronchial epithelial biopsy specimens obtained from persons with and without lung cancer were placed into short-term culture and serially transfected with retroviral constructs containing cyclin-dependent kinase (Cdk) 4 and human telomerase reverse transcriptase (hTERT), resulting in continuously growing cultures. The order of introduction of Cdk4 and hTERT did not appear to be important; however, transfection of either gene alone did not result in immortalization. Although they could be cloned, the immortalized bronchial cells did not form colonies in soft agar or tumors in nude mice. The immortalized HBECs have epithelial morphology; express epithelial markers cytokeratins 7, 14, 17, and 19, the stem cell marker p63, and high levels of p16(INK4a); and have an intact p53 checkpoint pathway. Cytogenetic analysis and array comparative genomic hybridization profiling show immortalized HBECs to have duplication of parts of chromosomes 5 and 20. Microarray gene expression profiling demonstrates that the Cdk4/hTERT-immortalized bronchial cell lines clustered together and with nonimmortalized bronchial cells, distinct from lung cancer cell lines. We also immortalized several parental cultures with viral oncoproteins human papilloma virus type 16 E6/E7 with and without hTERT, and these cells exhibited loss of the p53 checkpoint and significantly different gene expression profiles compared with Cdk4/hTERT-immortalized HBECs. These HBEC lines are a valuable new tool for studying of the pathogenesis of lung cancer.

Cell Growth Processes↗
PubMed2004

Hydrogen-bonding-directed layer-by-layer assembly of poly(4-vinylpyridine) and poly(4-vinylphenol): effect of solvent composition on multilayer buildup.

This paper describes the buildup of hydrogen-bonding-directed poly(4-vinylpyridine)/poly(4-vinylphenol) (PVPy/PVPh) multilayer film that was fabricated by layer-by-layer (LbL) assembly of PVPy and PVPh from an ethanol solution. UV-visible spectroscopy and Fourier transform infrared (FT-IR) spectroscopy revealed a uniform deposition process. The interaction between PVPy and PVPh was identified as hydrogen bonding through FT-IR spectroscopy and temperature-dependent IR spectral changes of the hydrogen-bonded multilayer. Notably, we discussed the effect of solvent conditions on the growth of PVPy/PVPh multilayer films monitored by UV-visible spectroscopy. It was found that increasing the ratio of N,N-dimethylformamide (DMF) in the mixed ethanol/DMF solvents resulted in a marked decrease of the amount of polymers adsorbed, which was attributed to the increased polarity of the adsorption solutions. Furthermore, the solvent stability of PVPy/PVPh multilayer film in mixed ethanol/DMF solvents with different DMF ratios was also investigated. As a result, a new method for tuning the structure of hydrogen-bonding-directed multilayer film was developed.

Ethanol↗
PubMed2004

Influence of substituents on two-dimensional ordering of oligo(phenylene-ethynylene)s--a scanning tunneling microscopy study.

Two-dimensional (2D) assemblies of alkoxy-substituted oligo(phenylene-ethynylene)s bearing different substituents adsorbed on highly oriented pyrolytic graphite (HOPG) were studied by using scanning tunneling microscopy. It was found that the introduction of different endgroups or a biethynylene linkage into oligo(phenylene-ethynylene)s can significantly change their 2D ordering on HOPG. The carboxylic endgroups can direct the conjugated oligomers to form ordered lines through intermolecular hydrogen bonding. The possibility of controlling the 2D assemblies of conjugated molecules is of importance in designing organic optoelectronic devices.

Journal Article↗
PubMed2004

Highly efficient dendrimer-based mimic of glutathione peroxidase.

In this communication, we report the synthesis of the three generations of Fréchet-type poly(aryl ether) dendrimers with a diselenide core that demonstrate generation-dependent glutathione peroxidase (GPx) activity with initial reduction rates as high as 2431.20 muM min-1 for the third-generation product, around 1400 times faster than Ebselen. It represents a successful example of using a dendrimer as a model for a GPx mimic.

Benzene Derivatives↗
PubMed2004

Characterization of the 3a protein of SARS-associated coronavirus in infected vero E6 cells and SARS patients.

Proteomics was used to identify a protein encoded by ORF 3a in a SARS-associated coronavirus (SARS-CoV). Immuno-blotting revealed that interchain disulfide bonds might be formed between this protein and the spike protein. ELISA indicated that sera from SARS patients have significant positive reactions with synthesized peptides derived from the 3a protein. These results are concordant with that of a spike protein-derived peptide. A tendency exists for co-mutation between the 3a protein and the spike protein of SARS-CoV isolates, suggesting that the function of the 3a protein correlates with the spike protein. Taken together, the 3a protein might be tightly correlated to the spike protein in the SARS-CoV functions. The 3a protein may serve as a new clinical marker or drug target for SARS treatment.

Animals↗
PubMed2004

In situ gamma ray-initiated polymerization to stabilize surface micelles.

Surfactant molecules containing hydrophobic long alkyl chains and hydrophilic groups can organize into various micellar structures both in bulk solution and at interface. However, because of the dynamical nature of surfactant micelles, efforts directed at fixing their structures in bulk solution by polymerization have met with limited success. Herein, we report a unique and simple method of stabilizing surface micelles of a low molecular weight surfactant 11-acryloyloxyundecyltriethylammonium bromide (AUTEAB) through in situ intramicellar polymerization on the mica surface. Atomic force microscopy (AFM) observations show that the cylindrical micellar structure formed by AUTEAB monomers at the mica/water interface is preserved after the in situ polymerization, and the stability of the polymerized surface micelles is greatly enhanced compared with that of the unpolymerized ones.

Journal Article↗
PubMed2004

Polyelectrolyte multilayer as matrix for electrochemical deposition of gold clusters: toward super-hydrophobic surface.

This communication describes the use of polyelectrolyte multilayer as a preformed matrix in electrochemical deposition to adjust the morphology of gold clusters, and only the surface covered with dendritic gold clusters shows a super-hydrophobic property, with the contact angle above 150 degrees and the tilt angle less than 1.5 degrees , after the surface further chemisorbed with a self-assembled monolayer of n-dodecanethiol.

Journal Article↗
PubMed2004

Two- and three-dimensional molecular organization of Schiff-base derivatives.

We have designed and synthesized a series of Schiff base derivatives, and studied their structural features in two-dimensional (2D) and three-dimensional (3D) states by combining scanning tunneling microscopy (STM) and X-ray diffraction experiments. The Schiff-base derivatives with short alkyl chains crystallize easily, which allows a detailed structural analysis by X-ray diffraction. Due to the strong adsorbate-substrate interactions, those bases with long alkyl chains easily form 2D assemblies on highly oriented pyrolytic graphite (HOPG). The STM images indicate also that the introduction of two methoxy groups into the molecule can change the structure of these 2D assemblies as a result of the increased steric hindrances, for example: the Schiff-base derivative, bearing both methoxy groups and C16H33 tails, forms 2D Moiré patterns, and an alignment of pairing Schiff-base molecules may be easily resolved. Conversely, the Schiff base derivative, bearing solely C16H33 tails, forms 2D non-Moiré patterns. It is demonstrated that the 3D structural features result from the compromise of intermolecular interactions of different molecular moieties. However, there is one more factor, which also governs the 2D structure: the adsorbate-substrate interaction. The 3D crystal structure may thus help to understand many factors involved in the formation of 2D structures, and would be helpful for designing new molecular assemblies with tailoring functions.

Journal Article↗