Search PubMed⌕ Search

Biomedical subjects

Y Wu

Publications and source records attributed to Y Wu.

At least 235 records · Page 13Linked to original sources
PubMed2001

[Effect of pentoxifylline on promoter activity of human alpha 1(I) procollagen gene].

OBJECTIVE: To study the effect of pentoxifylline (PTX) on promoter activity of human alpha 1(I) procollagen (COL1A1) gene and the influence of PTX on the promoter activity induced by insulin-like growth factor 1 and insulin. METHODS: The constructs of pCOLH2.5 containing -2483 approximately +42bp of the procollagen gene and chloramphenicol acetyltransferase (CAT) as reporter gene were transiently transfected into human skin fibroblasts. The cells were subsequently treated with PTX or IGF-1 or insulin, or PTX plus IGF-1 or insulin. The CAT activity was assessed 24h after PTX and the cytokines added. RESULTS: PTX of 0.4 mmol/L, 2 mmol/L, and 10 mmol/L decreased the CAT activity of pCOLH 2.5 to 82%+/-9%, 58%+/-8%, and 32%+/-13% of the control level, respectively. IGF-1 and insulin increased the activity of the construct. PTX could inhibit the CAT activity of pCOLH2.5 induced by IGF-1 and insulin. CONCLUSIONS: These studies indicate that PTX downregulates the promoter activity of the human COL1A1 gene, while IGF-1 and insulin upregulates it. PTX can inhibit the promoter activity induced by IGF-1 and insulin.

Collagen↗
PubMed2001

[Pests on zingiberaceous plants and their control in south China].

The pests on the zingiberaceous plants and their occurrence and damage as well as control have been investigated in the ginger plantation of South China Botanical Garden recently. 12 insect pests and 1 mite pest are common. To control them effectively, such as selecting loose, fertile soil as planting field with proper shade, applying healthy and vigorous seeds, seedling and rhizomes for propagation, regulating plant density, sanitizing the field in time are mostly recommended. The application of chemical and biological pesticides and the protection on the beneficial organisms are also stressed.

China↗
PubMed2001

[Detection of gangliosides in human milk with a high performance thin layer chromatography (HPTLC)].

OBJECTIVES: To determine the ganglioside composition in human milk during lactation, and to evaluate the biological significance. METHODS: The gangliosides extracted from 68 milk samples were examined with a high performance thin layer chromatography (HPTLC). RESULTS: The concentration of total lipid bound sialic acid was 7.8-10.4 microliters/ml. Four gangliosides were found and designated as GM3, GD3, GX1 and GX2, respectively. GX1 and GX2, which had not been described previously, were tentatively assumed to be gangliosides of the c-pathway because they did not react to the GA1 antibody after sialidase treatment. GD3 and GM3 were the major gangliosides in human milk (accounted for 50%-65%). CM3 decreased sharply at eight days postpartum. Both GM3 and GD3 changed significantly during lactation (GM3, r = 0.65, P < 0.01; GD3, r = -0.58, P < 0.01). CONCLUSIONS: Four gangliosides, GM3, GD3, GX1 and GX2 were found in human milk. Both GM3 and GD3 changed significantly during lactation.

Adult↗
PubMed2001

[Cytogenetic analysis on 1058 cases of acute nonlymphocytic leukemia].

OBJECTIVE: To evaluate the karyotypic status in a large series of acute nonlymphocytic leukemia(ANLL) cases. METHODS: A total of 1058 cases of de novo ANLL were studied. Chromosome preparations were made on bone marrow cells using direct method and short-term culture. Karyotypes were analyzed by R-banding in all cases and G-banding in some cases in addition. RESULTS: Six hundred and thirty cases (60%) had clonal chromosomal abnormalities. 25 categories of major karyotypic abnormalities were found. Among them, 11 were the specific chromosomal rearrangements seen in 481 cases, accounting for 76% of the total number of patients with karyotypic abnormalities. Isolate trisomy 8 (21 cases) was the most common numerical abnormality. t(15;17)(211 cases) and t(8;21)(200 cases) were the most frequent structural abnormalities. The 1.1% of M(2), 72% of M(3), 71% of M(4E0), 50% of M(2), 6 % of M(5) and 1.4% of M(2) had t(7;11), t(15;17), inv(16), t(8;21), t/del(11q 23) and t/del(12p) abnormalities, however, the 100% of t(7;11), 100% of t(15;17 ), 100% of inv(16), 88.5% of t(8;21), 83% of t/del(11q23) and 62% of t/del(12p) were detected in patients with M(2), M(3), M(4E0), M(2), M(5) and M(2) subtypes, respectively. CONCLUSION: By conventional banding technique, including R- and G-bandings, 60% of patients with ANLL may be found to have clonal chromosomal abnormalities which are predominantly specific chromosomal rearrangements correlated with specific FAB subtypes. Thus, karyotype is an important indicator for diagnosis and classification of ANLL.

Adolescent↗
PubMed2001

[Detection of monosomy 7 or 7q- in cases of myelodysplastic syndrome].

OBJECTIVE: To investigate the value of interphase fluorescence in situ hybridization(FISH) in the detection of monosomy 7 (-7)or deletion of long arm of chromosome 7(7q-) in the cases of myelodysplastic syndrome (MDS). METHODS: Forty-six cases of MDS and 10 normal controls were studied simultaneously by conventional karyotype analysis and interphase FISH technique using SpectrumRed directly labeled DNA specific probe for 7q32. Two hundred interphase cells were analyzed for each case and the cells with one red hybridization spot<7% were regarded as positive. RESULTS: Three cases displayed -7/7q- by conventional cytogenetics(CC) and were confirmed by interphase FISH. Six cases in 43 cases who did not show -7/7q- by CC displayed -7/7q- by interphase FISH. CONCLUSION: Interphase FISH is very useful for the detection of -7 or 7q- in MDS and it is more sensitive than CC.

Adolescent↗
PubMed2001

Sodium current in NG108-15 cell inhibited by scorpion toxin BmKAS-1 and restored by its specific monoclonal antibodies.

Effect on Na+ current of BmKAS-1, a novel polypeptide purified from the venom of Chinese scorpion Buthus martensi Karsch (BmK), has been investigated in differentiated NG108-15 cells by using patch-clamp whole-cell recording. Neutralizing effect of four monoclonal antibodies of BmKAS-1 (mAb #2, #3, #4, and #5) has also been observed. The results showed that Na+ current was irreversibly inhibited by BmKAS-1 and the inhibitory effect was abolished by mAb #2 and #5, but not by mAb #3 and #4.

Animals↗
PubMed2001

[Distribution of polycyclic aromatic hydrocarbon in core sediments of the Bohai Straight].

Thirteen compounds of PAHs were identified by GC in the core sediments of Bohai Straight (S44 and T4 Stations). The distribution and source identification were studied with the two core sediments. The total concentrations changed from 60.3 ng/g to 2076.5 ng/g. Though the contamination of PAHs in the study area is quite modest, some carcinogenic compounds were detected in most samples. From the indicators such as Pen/Anth and Fluo/Pyr etc. the dominated origin of PAHs in S44 Station is pyrolytic origins. However, in T4 Station, a mixture of pyrolysis and petroleum origin is suggested in this area. The distribution of PAHs in the core sediments also could be a good indicative of the contribution of human activity.

Geologic Sediments↗
PubMed2001

[Kinetic study on photocatalytic degradation of p-chlorobenzoate at different light intensities].

Kinetics of photocatalytic degradation were investigated at different light intensities using para-chlorobenzoate as a model pollutant. It was experimentally found that the Langmuir-Hinshelwood model could satisfactorily describe all the kinetic processes. However, the two crucial parameters involved in the L-H model were dependent of the incident light intensity. With elevated light intensity, the rate constant, kr, increased whereas the apparent adsorption constant, Ks, decreased. Grossly, both kr and Ks-1 were correlated with the light intensity in a power law. The experimental discovery implies that the photonic efficiency would be much deteriorated with increased radiation intensity although the reaction rate can be enhanced. Applying mild light intensity might be one of the critical strategies in photocatalytic reactor design to improve the photonic efficiency.

Catalysis↗
PubMed2001

Accuracy of three-dimensional quantification of left ventricular function using magnetic sensor acquisition: a dynamic in vitro model.

OBJECTIVE: To evaluate the accuracy of a three-dimensional (3D) magnetic position sensor system in the quantification of ventricular stroke volumes in a dynamic model. METHODS: A latex balloon model of the left ventricle was suspended in a water bath connected to a pump producing 10 different pulsatile stroke volumes (15-65 ml/beat). Scanning was performed using a 5.0 mHz transducer mounted with a Flock of Birds (FOB) magnetic receiver (GE System Five). The probe was scanned to sweep continuously across and over the balloon volume over 3-7 seconds. Digital loops were stored on magneto-optical disks and reviewed retrospectively using 3D Echopac software (GE) based on Simpson's method and compared with a two-dimensional (2D) biplane area-length method (1/2 L x R) measurements at end systole and end diastole. Both 3D and 2D derived stroke volumes were compared with the reference stroke volume calculated by direct measurement of balloon capacity. RESULTS: There was an improved correlation between 3D stroke volume and reference stroke volume (y = 0.91x + 0.41, r = 0.97, SEE = 2.83 ml, P = 0.0001) compared to 2D stroke volume and reference stroke volume (y = 0.49x + 8.68, r = 0.87, SEE = 3.87 ml, P = 0.0011, difference between 2D and 3D P < 0.003). CONCLUSION: 3D magnetic FOB scanning is practical, accurate and should facilitate assessment of left ventricular function.

Echocardiography, Three-Dimensional↗
PubMed2001

Modulation of the inflammatory response in the cardiomyocyte and macrophage.

Numerous cardiac disease processes have been linked to the overproduction of nitric oxide (NO) via inducible nitric oxide synthase (iNOS) in the cardiovascular system. Chronic and acute exposure to hyperphysiologic levels of NO has been suggested as an agent in chronic transplant rejection, various cardiomyopathies, reperfusion injury, and the inflammatory state following cardiopulmonary bypass. Proinflammatory cytokines and inflammatory cell types, such as macrophage and neutrophils, have also been implicated in the pathophysiology associated with the previously mentioned syndromes. Previous work by this group has shown that lipopolysaccharide (LPS) in combination with tumor necrosis factor-alpha (TNF-alpha) can increase iNOS expression and the production of NO in macrophage. With this in mind, we hypothesized that increased iNOS expression and NO production generated by LPS and TNF-alpha in the macrophage could be mimicked in the cardiomyocyte and potentially account for some aspect of the cardiac dysfunction attributed to NO. Furthermore, this increased expression of iNOS and NO production could be returned to control using the glucocorticoid, dexamethasone, a known iNOS transcription blocker. Using fetal rat cardiomyocytes in primary culture cell line and a murine macrophage cell line, RAW 264.7, the expression of iNOS was quantified with specific FITC-conjugated antibodies using fluorescence activated cell sorter (FACS) and NO production with a Bioxytech nitric oxide spectrophotometric assay. The myocytes and macrophage were separated into three groups, Control, TNF + LPS, and (+) Dexamethasone. The control groups received no TNF or LPS or dexamethasone, TNF + LPS groups received TNF-alpha and LPS for 8 hours with no dexamethasone, and the (+) Dexamethasone groups were pretreated with dexamethasone for 8 hours and stimulated with TNF-alpha and LPS along with a second 8-hour treatment of dexamethasone. The macrophage cell groups treated with TNF-alpha and LPS showed a 335% increase over control in iNOS expression, and NO production was increased 494% from control. Macrophage treated with dexamethasone experienced an attenuation of iNOS expression of 200% toward control from stimulated levels and 202% decrease in NO production from stimulated levels toward control. Cardiomyocytes exhibited no statistically significant change in the expression of iNOS or NO production with stimulation or dexamethasone treatments. In conclusion, iNOS and NO were elevated in macrophage, which can be blunted in the presence of dexamethasone in the macrophage. Curiously, iNOS could not be stimulated in the cardiomyocyte, suggesting inflammatory cells may be largely responsible for the elevated iNOS and NO experienced in some cardiovascular diseases. The clinical relevance of this study is the introduction of specific iNOS inhibitors into the cardiopulmonary bypass circuit could serve as a potential mechanism for modulating the inflammatory response surrounding cardiopulmonary bypass. Likewise, therapeutic glucocorticoid administration could improve outcomes for patients with inflammatory cardiovascular disease states related to elevated NO production.

Animals↗
PubMed2001

[Identification of red kojic from different habitats with clustering analysis by near-infrared diffuse reflectance spectrometry].

OBJECTIVE: To provide a new method for identifying Red kojic. METHODS: Being controled with the Aspergillus terreus, near-infrared diffuse reflectance spectroscopy combining with clusering analysis was used in the identification of Red Kojic made by M. purpureus fermentation from 18 different habitats. RESULTS: We can easily distinguish the Red Kojic from different habitats and the Aspergillus terreus. The results are consistent in some degree with that of morphologic study. CONCLUSION: This method is a new, rapid, simple and low cost assay technique being able to be used in the quality control of Red Kojic.

Cluster Analysis↗
PubMed2001

[Comparative effects of decreasing viscosity in different preparations of Chinese angelica root and ginseng].

OBJECTIVE: To compare the effects of different preparations of Chinese angilica root and ginseng on decreasing whole blood viscosity and plasma viscosity in rats. METHOD: The hemorheological method was used in vivo or in vitro and a Decreasing Viscosity Index (DIV) was defined as a comparative scalar. RESULTS: In the effect of the groups of Chinese angilica root on decreasing viscosity, the effect of whole root group was the best and the effect of main root group was better than that of the tributary root group. Meanwhile the same effect of transplant wild ginseng group was greater than that of dried raw ginseng group. CONCLUSION: This work provided some fundamental evidences for clinical application and pharmacological data for the quality evaluation.

Angelica sinensis↗
PubMed2001

Inhibition by nociceptin on excitatory non-adrenergic non-cholinergic response in guinea pig airways.

AIM: To study the effect of nociceptin (NC), a newly discovered heptadecapeptide, and U-50488H, a kappa-opioid receptor agonist, on excitatory non-adrenergic non-cholinergic (eNANC) constriction responses in guinea pig isolated bronchus. METHODS: An eNANC response was induced by electric field stimulation (EFS) in the preparation via activation of the sensory nerve terminals. The effect of NC and U-50488H was analyzed on the response. RESULTS: Nociceptin 0.001 - 0.1 micromol/L inhibited the eNANC constriction which was induced by EFS but not by capsaicin in guinea pig bronchus. The constriction inhibited by NC 0.01 micromol/L was (43 +/- 31) % compared with the control. After pretreatment with naloxone 0.1 micromol/L, the constriction was inhibited by (46 +/- 28) %, without marked change compared with the above figure. IC50 (95 % of confidence limits) was 6.12 (3.8 - 9.9) nmol/L. U-50488H also inhibited the EFS-evoked eNANC constriction and the effect was abolished after pretreatment with naloxone. IC50 (95 % of confidence limits) was 1.08 (0.5 - 2.2) micromol/L. Capsaicin 0.01 - 1 micromol/L caused a cumulative constriction response in the preparation. Moreover, the effect of capsaicin was not affected by pretreatment with NC 0.01 micromol/L or U-50488H 0.1 micromol/L. The constriction induced by exogenous neurokinin A, were also unaffected by treatment with NC 0.01 micromol/L or U-50488H 0.1 micromol/L in isolated bronchus. CONCLUSION: Nociceptin inhibits EFS-induced eNANC constriction, which is not reversed by naloxone, while U-50488H inhibits EFS-induced eNANC response via activation of opioid receptor in guinea pig airways.

3,4-Dichloro-N-methyl-N-(2-(1-pyrrolidinyl)-cycloh↗
PubMed2001

[Effect of Zn2+, Cd2+ and their combined on Ca, Fe and Mn uptake by wheat seedlings].

The effect of Zn, Cd and their combination on Ca, Fe and Mn uptake by wheat seedlings was studied with solution culture. The result shows the Zn and Cd contents of wheat increased with increasing concentrations of Zn2+ and Cd2+ in solution, while there was a difference between single and compound treatments. Zn affected Cd uptake by wheat, and Cd inhibited Zn uptake. The uptake of Ca and Mn reduced with the increase of Zn2+ and Cd2+ in solution. The uptake of Fe increased with increasing Zn2+ and Cd2+ concentrations in single treatment, while decreased in compound treatment. The interactive effect of Zn and Cd was also related to the parts of plants.

Cadmium↗
PubMed2001

[Changes in plasma free amino acid concentrations in rats during sepsis].

OBJECTIVE: To explore the relationship between plasma free amino acid concentrations and skeletal muscle proteolysis in rats during sepsis. METHODS: An animal model of sepsis in rats was established by administering endotoxin into the peritoneal cavity. The plasma concentrations of free amino acid, ALT, AST, cortisol, TNF-alpha and IL-6 were determined. The rats were randomly divided into normal control, 2, 6, 12 and 24 h groups after administration of endotoxin(8 rats for each group). RESULTS: The total plasma free amino acids concentrations fluctuate within normal range within 24 h after administration of endotoxin. A marked decrease in BCAA (branch-chainamino acid) was observed at 2, 6 and 12 h after administration of endotoxin, but aromatic amino acids (AAA) increased in varying degrees. BCAA/AAA was lower at 2 h and 6 h as compared with that of the normal control, while Phe/Tyr increased obviously at every time point. Lys, Sar, Cys and P-Ser showed no significant changes within 24 h after the administration of endotoxin. Thr, Glu, Orn, His, 3-MH and Ala increased during sepsis, and other amino acids more or less decreased. Plasma concentrations of ALT, AST, cortisol, TNF-alpha and IL-6 obviously increased within 24 h after the administration of endotoxin(P < 0.01). Cortisol peaked at 6 h and IL-6 peaked at 12 h, while TNF-alpha at 2 h. CONCLUSION: The results suggested that metabolic disorder of plasma free amino acids during sepsis is due to enhancement of skeletal muscle proteolysis and liver overloading.

Alanine Transaminase↗
PubMed2001

[Motor vehicle source contributions to air pollutants in Beijing].

Beijing's motor vehicle emission inventory based on GIS technology was developed, and used to estimate the contribution rate of different types of vehicles and different areas of vehicles to the total vehicular emissions in the urban area of Beijing. ISCST3, a gaussian dispersion air quality model, was modified at low wind speed condition, and then used to facilitate the study of the spatial and temporal distribution of CO and NOx concentrations in Beijing. It was shown that vehicle source emissions of CO and NOx accounted for 76.8% and 40.2%, respectively, of the total emissions in 1995. The simulation results also showed that emissions from the vehicle sources had contributed 76.5% and 68.4% of the total CO and NOx concentrations in urban atmosphere of Beijing in 1995, and were even higher at down-town and near the arteries. Therefore, strategies for CO and NOx pollution control will of necessity need to focus on the vehicle sources.

Air Pollutants↗
PubMed2001

[The influence factors of SO2 removal in flue gas with a pulsed corona discharge].

The influence of the operation parameters on SO2 removal rate with a pulsed corona discharge was studied in this paper, in order to promote the industrial applications of this technology. The flow rate of the flue gas was 1000-3000 m3/h. The SO2 removal rate reached 80%. The range of SO2 concentration in flue gas was 1000-2000 ml/m3. The flue gas temperature was 60 degrees C-80 degrees C. The molecule ratio of NH3 to SO2 was 2. The energy consumption was 3-5 W.h/Nm3. The wire-plane electrode structure and a positive high voltage pulse power supply were used in the experiment.

Sulfur Dioxide↗