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Biomedical subjects

Ying Zhou

Publications and source records attributed to Ying Zhou.

At least 55 records · Page 3Linked to original sources
PubMed2004

[Study of tracheal regeneration after injury induced by 5-fluorouracil in rats].

OBJECTIVE: Localization of tracheal stem cells in rat trachea. METHODS: Extracorporeal tracheal injury (Wistar rats) was induced by 5-FU. The process of regeneration was observed and analyzed by light microscopy, electron microscopy, and immunohistochemistry. RESULTS: Twelve hours after treatment with 5-FU, the tracheal epithelium shed and cells with naked nuclei were seen located sparsely on the basement membrane. Six hours after removal of 5-FU, the tracheal rings were covered with flattened epithelium. These cells were poorly differentiated under electron microscopy. Immunohistochemistry showed few proliferating cell nuclear antigen (PCNA)-negative cells sparsely scattered among PCNA-positive cells on the basement membrane. Nine hours later, electron microscopy found that these cells differentiated into mucous cells and ciliated cells. Forty-eight hours later, the tracheal rings were entirely covered by pseudostratified ciliated columnar epithelium. CONCLUSIONS: A small number of G(0) cells with naked nuclei are located sparsely on the basement membrane of the trachea. Tracheal epithelium regenerates by proliferation and differentiation of these cells. It is likely that some of these G(0) cells on the tracheal basement membrane represent tracheal stem cells.

Animals↗
PubMed2004

[Identification of Mycobacterium species by PCR-restriction fragment length polymorphism of the 65-kDa heat shock protein gene using capillary electrophoresis].

OBJECTIVE: To set up HSP65 PCR-RELP capillary electrophoresis method to rapidly identify the mycobacterium to species. METHODS: A 440 base pair long part of HSP65 gene of each mycobacterium was amplified by PCR. After the amplification products were fully digested by restriction endonucleases BstE II and Hae III respectively, capillary electrophoresis with laser induced fluorescence detector was used to separate and detect the digested fragments. RESULTS: All of the 7 tested mycobacterium species have their own unique patterns of digested fragments, all fragments can be well separated. CONCLUSION: Capillary electrophoresis can give more higher accuracy and sensitivity in identifying mycobacterium species.

Bacterial Proteins↗
PubMed2004

[Apoptosis of hepatocarcinoma cell line HLE induced by the combination of wild type P53 gene and 1,2:5,6-dianhydro-3,4-diacetylgalactitol].

BACKGROUND & OBJECTIVE: P53 gene is a tumor suppressor gene,and its mutation in human tumor cells is frequently observed. Previous studies revealed that wild type p53 (wt-p53)gene can suppress proliferation ,and induce apoptosis of tumor cells. However,the enhancive effect of wt-p53 on apoptosis of tumor cells is not so obvious when it is used alone. Therefore,it is a new field for tumor research that wt-p53 gene combined with drug is used to enhance apoptosis rate of tumor cells. This study was to investigate the enhancement effect of the combination of wt-p53 and 1,2:5,6-dianhydro-3,4-diacetylgalactitol (DADAG)on apoptosis of human hepatocarcinoma cell line HLE. METHODS: HLE cells were transfected with pUHD10-3-p53 plasmid contained wt-p53 gene,and treated with DADAG. After 96-hour treatment,apoptosis was evaluated by flow cytometry and DNA electrophoresis. RESULTS: The apoptosis rates were: 1.4% in untreated group, 3.5% in pUHD10-3-transfection group, 32.6% in DADAG group, 43.4% in pUHD10-3-p53-transfection group, and 74.6% in pUHD10-3-p53-transfection plus DADAG-treatment group. DNA ladder was observed in pUHD10-3-p53-transfection plus DADAG-treatment group. CONCLUSION: Apoptosis of HLE cells could be induced by both wt-p53 gene and DADAG,and the effect was more obvious when HLE cells were treated by the combination of wt-p53 gene and DADAG.

Antineoplastic Agents, Alkylating↗
PubMed2004

[Preliminary study on gene related to acid tolerance of Streptococcus mutans].

OBJECTIVE: To construct an acid-sensitive mutant of Streptococcus mutans (S. mutans) by transposon mutagenesis and to find a new gene related to the acid tolerance of S. mutans. METHODS: The transposon Tn917 was delivered into S. mutans UA159 by the temperature-sensitive plasmid pTV1-OK bearing Tn917 and transposition of Tn917 was induced after incubation at non-permissive temperature (42 degrees C). Transposants harboring Tn917 in the chromosome were screened for the selection of mutant that had diminished growth at low pH. Southern analysis was performed with EcoRI (no cut within Tn917) digests of S. mutans UA159 and the selected aid-sensitive mutant, with DIG-labeled probe of 4.3 kb KpnI fragment of pTV1-OK containing Tn917. Genetic backcross experiment was performed by transforming the genome of the mutant to another S. mutans strain MT8148 to determine the linkage of Tn917 insertion to the change of phenotype (acid-sensitivity). Comparison of the abilities to grow at low pH, the glycolytic pH drop and killing pH values were done between the acid-sensitive mutant and the parent strain. The asymmetric PCR method was used to obtain the fragment flanking Tn917 and the PCR products were cloned to pMD18-T vector for sequencing. RESULTS: One mutant that showed no growth at pH 5.0 was isolated from 2 316 transposants and was named as b23. Southern analysis and genetic backcross experiment confirmed the linkage between single Tn917 insertion into the chromosome and the phenotypic change (acid sensitive). b23 was less acid tolerant than UA159 in that it showed poorer growth at low pH and higher glycolytic pH minimum and higher killing pH. BLAST results indicated that Tn917 inserted into the genome of S. mutans UA159 at the site of 996 123 bp. CONCLUSION: An acid-sensitive mutant of S. mutans was successfully constructed and a new gene that is responsible for the acid tolerance in S. mutans UA159 was revealed.

Genes, Bacterial↗
PubMed2004

[Expression of EDAG-1 gene in human leukemia and lymphoma cell lines].

BACKGROUND & OBJECTIVE: Embryonic development associated gene 1 (EDAG-1), located at chromosome 9q22, is specially expressed in hematopoietic cells, and related to the regulation of hematopoietic system. This study was designed to explore relationship between pathogenesis of leukemia, lymphoma and EDAG-1 through analyzing the structure of EDAG-1 coding region, and its expression in these cell lines. METHODS: Fifteen leukemia and lymphoma cell lines, HEL, K562, HL-60, Namalwa, Raji, J111, Jurkat, HuT 78, MEG-01, U937, 6T-CEM, HPB-ALL, KG-1a, THP-1, and DAMI, were selected to observe the expression of EDAG-1 by reverse transcriptase-polymerase chain reaction (RT-PCR), EDAG-1 cDNA coding fragments (1.5 kb) were purified to construct the corresponding recombinant plasmid. Then, the plasmid was sequenced to analyze mutation of the coding region. The expression of EDAG-1 protein, and mRNA in these cell lines were detected by Western blot, and Northern blot; the rearrangement and amplification of EDAG-1 genome in these cell lines were detected by Southern blot. RESULTS: EDAG-1 mRNA and protein were highly expressed in erythroleukemia cell lines (K-562, HEL), megakaryoblast leukemia cell lines (DAMI, MEG-01), and T cell leukemia cell line (Jurkat), while no gene mutation was found in coding region, no amplification and rearrangement of genome was detected in these cell lines. EDAG-1 was absent in HL-60 cell line, and rearranged in HuT 78 cells. CONCLUSION: EDAG-1 may relate with pathogenesis of erythroleukemia and megakaryoblast leukemia; its coding region may have no relation with the mechanism of its activation.

Burkitt Lymphoma↗
PubMed2004

[Study on peparation of anemonin from Ranunculus japonicus Thunb].

OBJECTIVE: To study the preparation of anemonin from Ranunculus japonicus Thunb. METHODS: The best conditions of preparation for anemonin were optimized with monosyllabic experiments, such as using the purity of anemonin as a index for best selection of dying tempreture and the extraction ratio as another index for the concentration of NaCl and extracting times. The structures were clucidated on the basis of UV, IR, 1HNMR, 13CNMR, 1H-1H COSY, HMQC and HMQC spectra and chemical reactions and the purity is measured by HPLC. RESULTS: The best conditions for the extraction techniques of anemonin were 15% NaCl, four extracting times, 60 degrees C (0.08 Mpa) for drying. The purity of anemonin was 99% and yield rate was 0. 72 per thousand. Its quality was controlled. CONCLUSION: The preparation techniques are feasible and convenient.

Arabidopsis Proteins↗
PubMed2003

APP processing is regulated by cytoplasmic phosphorylation.

Amyloid-beta peptide (Abeta) aggregate in senile plaque is a key characteristic of Alzheimer's disease (AD). Here, we show that phosphorylation of amyloid precursor protein (APP) on threonine 668 (P-APP) may play a role in APP metabolism. In AD brains, P-APP accumulates in large vesicular structures in afflicted hippocampal pyramidal neurons that costain with antibodies against endosome markers and the beta-secretase, BACE1. Western blot analysis reveals increased levels of T668-phosphorylated APP COOH-terminal fragments in hippocampal lysates from many AD but not control subjects. Importantly, P-APP cofractionates with endosome markers and BACE1 in an iodixanol gradient and displays extensive colocalization with BACE1 in rat primary cortical neurons. Furthermore, APP COOH-terminal fragments generated by BACE1 are preferentially phosphorylated on T668 verses those produced by alpha-secretase. The production of Abeta is significantly reduced when phosphorylation of T668 is either abolished by mutation or inhibited by T668 kinase inhibitors. Together, these results suggest that T668 phosphorylation may facilitate the BACE1 cleavage of APP to increase Abeta generation.

Alzheimer Disease↗
PubMed2003

Particle swarm optimization-based approach for optical finite impulse response filter design.

This study presents what is to our knowledge a new and efficient method for the design of an optical finite impulse response (FIR) filter by employing a particle swarm optimization technique. With the method proposed, the design of an optical FIR filter, which is able to provide an arbitrary spectrum output based on crystal birefringence, could be implemented with good performance and high efficiency. The design procedure is discussed. A typical example of a green/magenta filter used in a liquid crystal on silicon projection display is included to demonstrate the feasibility and efficiency of this method in this design process as compared with simulated annealing.

Journal Article↗
PubMed2003

[Factors dominating the sorption of bentazon in soils].

Adsorption isotherms of bentazon in six selected soils were measured by using batch sorption method. Meanwhile the mean partial free energy change of chemical in sorption process was also calculated. The results showed the adsorption isotherms of herbicide in five soils all were linear, distribution coefficients (Kd) ranged from 0.14 mL.g-1 to 0.31 mL.g-1, and the extent of soils adsorption the herbicide followed: Deqing paddy soil > Ji'an paddy soil(pH4.79) > Yuhang paddy soil > Lin'an red soil > Ji'an paddy soil(pH7.36) > Deqing loess. Investigation of Kd vs. properties of soils indicated that both of the pH and content of soil organic matters were dominating factors that affected the adsorption of bentazon in soils, and adsorption of bentazon in soils equated the partitioning of neutral and anion form bentazon into soil organic, which was independent of the natural of soil organic matters.

Adsorption↗
PubMed2003

[Psychological aspects of subjective tinnitus].

OBJECTIVE: To investigate the psychological aspects of tinnitus and so as to treat them more effectively. METHOD: A total of 225 patients with first complain of subjective tinnitus was studied with interviewing, Zuang's self-rating scale of depression and tinnitus questionnaire to evaluate their psychological issues. RESULT: All patients showed obvious psychological problems. 21% of patients were resulted from psychological causes. 67.7% of patients were resulted in server psychological responses. The rest patients showed not only psychological causes but also psychological responses. CONCLUSION: Our results suggest that there is close relationship between tinnitus and psychological issues. Tinnitus questionnaire and tinnitus retraining therapy are powerful tools in diagnosing and treating psychological issues in tinnitus patients.

Adolescent↗
PubMed2003

[Simultaneous determination of copper and iron by flow-injection catalytic kinetic spectrophotometry with multi-channel detector].

The simultaneous determination of copper and iron by catalytic kinetic spectrophotometric method with back propagating artifical neural net (BP-ANN) was studied based on the catalysis of Cu(II) and Fe(III) to the reaction of rhodamine B hydrogen peroxide in the range of pH 3-9. The determination was performed by the construction of pH gradient and a CCD-diode array detector with a microcomputer. The optimum conditions of reaction and flow injection were studied. The determination limits for copper and iron were 0.10 and 0.21 microgram.L-1, respectively. The sampling rate was 10 samples per hour. The proposed method has been used to determine Cu(II) and Fe(III) in certified reference materials and food samples with satisfactory results. The average values of spiked recovery were 93.3%-100.2% with RSD of 0.6%-7.5%.

Animals↗
PubMed2003

[Changes of pulmonary tissue area density and their mechanisms in rats with hypoxic pulmonary hypertension].

OBJECTIVE: To investigate the changes of pulmonary tissue area density and their mechanisms in rats with hypoxic pulmonary hypertension (HPH). METHODS: 54 Wistar rats were divided into hypoxia 10 d (n = 12), 20 d (n = 12), 30 d (n = 12) groups and control group (n = 18). The rats in hypoxia groups were exposed to a simulated hypoxia environment at a height of 5 km above sea level to establish HPH models. The changes in pulmonary tissue area density and pathological morphology were determined by image analysis, optical microscope, electron microscope and histochemistry. RESULTS: After hypoxia, the pulmonary tissue area density markedly increased on 10 d (27.08% +/- 1.29%, P < 0.05), especially on 20 d (31.33% +/- 0.27%) and 30 d (31.10% +/- 1.95%) while that in control group was 22.78% +/- 1.17% (P < 0.01). The area density on 20 d was higher than that on 10 d (P < 0.05) but there wasn't significantly different between 10 d and 30 d (P = 0.057) after hypoxia. Pathological examination showed: edema and collapse of pulmonary tissue, swelling and degeneration of type II alveolus epithelial cells (PII); congestion, accumulation of polymorphonuclear neutrophils and platelets in capillaries; swelling and degeneration of endothelial cells, thickening of basement membranes. CONCLUSIONS: Hypoxia can induce increase in pulmonary tissue area density and decrease in aerial exchange area in alveoli. These changes may be related to the pulmonary collapse caused by the damage of PII and pulmonary surfactant system, structural remodeling of small pulmonary arteries, increase in blood cells and protein granules in alveolar cavity.

Animals↗
PubMed2002

A survey of Cdk5 activator p35 and p25 levels in Alzheimer's disease brains.

P25, a calpain cleavage product of the cyclin-dependent kinase 5 (Cdk5) activator p35, causes prolonged activation of Cdk5. Although p25 has been shown to accumulate in brains of patients with Alzheimer's disease (AD), it is not known whether p25 accumulation in AD is brain region-specific. We analyzed the amounts of p25 and p35 in human autopsy samples from multiple brain regions including frontal cortex, inferior parietal cortex and hippocampus using immunoblotting assays. Our results show that the p25-p35 indices are higher in AD than in the control groups in all three brain regions. The most significant difference in p25-p35 indices between AD and control groups is in the frontal cortex. No significant difference in calpain activity between AD and control groups is observed, indicating that postmortem calpain activation cannot account for the elevation of p25/p35 ratios in AD brains. Our results support the notion that p25 accumulation deregulates Cdk5 activity in AD brains, and the deregulated Cdk5 activity may contribute to the pathogenesis of AD.

Alzheimer Disease↗
PubMed2002

Evidence that the KH RNA-binding domains influence the action of the E. coli NusA protein.

The NusA transcription elongation protein, which binds RNA, contains sequences corresponding to the S1 and KH classes of identified RNA binding domains. An essential function in E. coli, NusA is also one of the host factors required for action of the N transcription antitermination protein of lambda. Tandem KH domains have been identified downstream of the S1 domain. We changed the first Gly to Asp of the GXXG motif, a tetrapeptide diagnostic of KH domains, of both NusA KH domains. The change in the first, G253D, has a large effect, while the change in the second, G319D, has a small effect on NusA action. The changes in both KH domains interfere with NusA binding to RNA. A change of a highly conserved Arg in the S1 domain, R199A, has previously been reported to interfere with RNA binding while exerting a small effect on NusA action. However, a nusA allele with both the R199A and G319D changes encodes a functionally inactive NusA protein. These studies provide direct evidence that the both KH as well as the S1 RNA binding domains are important for NusA action in support of bacterial viability as well as transcription antitermination mediated by the lambda N protein.

Amino Acid Substitution↗
PubMed2002

[A novel alternative splicing isoform of vascular endothelial growth factor gene in human beings].

OBJECTIVE: To investigate a new alternative splicing isoform of vascular endothelial growth factor (VEGF) gene in human bejings. METHODS: The total RNA of the lung tissue of a legally aborted 4-month-old human fetus was isolated and then amplified by RT-PCR. The amplified product was cloned into the pMD18-T plasmid and pcDNA3.1(-). Then sequence analysis was conducted. RESULTS: The electrophoresis of the RT-PCR product showed one short band of VEGF121 comprising of 487 bp and a long band with two fragments: one normal VEGF165 comprising of 619 bp and one fragment comprising of 639 bp which was the same VEGF165 nucleotide sequence with a 20 bp fragment inserted between exon 3 and exon 4. Sequence analysis showed that this 20 bp long nucleotide was inserted from the 3' end of the third intron that contained splicing signal, thus causing shift mutation in reading frame of VEGF gene and early appearance of the stop code UAG in the middle of exon 4. CONCLUSION: A new alternative splicing isoform of VEGF has been identified in the lung tissue of a legally aborted human fetus. Its biological significance remains to be further investigated.

Alternative Splicing↗