Search PubMed⌕ Search

Biomedical subjects

J Wu

Publications and source records attributed to J Wu.

At least 973 records · Page 54Linked to original sources
PubMed1997

[Study on the stunted culture of trees of Scaphium lychnophorum].

Taking these cultural practices, grafting by the ingraftment of side branch on the place of flowering with the dwarf stock, tip pruning on time to make branches growing and rational pruning etc can make the trees of Scaphium lychnbophorum dwafing effectively. The stunted trees are only high 3-5 m and their branches are only high about 1 m from the ground. Some of them first flower until five years after they are cultivated.

Malvaceae↗
PubMed1997

[Improvement of the assay for pre-S2 Ag/Ab detection and its application in different patients].

A new ELISA inhibition test for measuring serum Pre-S2Ab was developed to avoid the "double positive" phenomenon. One hundred and twenty samples with Pre-S2Ab negative were detected for Pre-S2Ab, the critical range for Pre-S2Ab in normal population was confirmed: a positive result was decided while the inhibition ration was over 50%, a negative result was decided while the inhibition ratio was less than 34%, and a dubious result was decided while the ratio was over 34% but less then 50%. At the same time, serum samples from sixty patients with chronic hepatitis B were detected for Pre-S2Ag and Pre-S2Ab, it showed that (1) the positive ratio of HBV DNA in patients with Pre-S2Ag positive was much higher than in patients with Pre-S2Ag negative (P < 0.01); (2) to the 46 patients with HBV DNA positive, Pre-S2Ag had a better relationship with HBV DNA than the HBeAg/Ab did (P < 0.01). Furthermore, to patients with acute hepatitis B, the presence of Pre-S2Ab was closely related to the prognosis of the disease, and the Pre-S2Ab assay could also be used to evaluate the preventive effect of HB vaccine containing Pre-S2Ag.

Enzyme-Linked Immunosorbent Assay↗
PubMed1997

[Clinical study on reversal of multidrug resistance in refractory and relapsed acute leukemias by cyclosporin A].

OBJECTIVE: To explore the clinical implication of reversal of multidrug resistance (MDR) by cyclosporin A (CsA) in refractory and relapsed acute leukemias. METHODS: The expression of p170 was assayed by immunocytochemical method (Avidin-Biotin Complex, ABC) using a monoclonal antibody JSB-1 against P-170. The P-170 positive cases were randomly divided into two groups:trial group (with CsA as revertant) and control group (without CsA), and the blood concentration of CsA was detected by HPLC. RESULTS: The complete remission rates were 53% and 20% in trial and control group, respectively (P<0.05), and the reversing effect was positively correlated with blood concentration of CsA. CONCLUSION: CsA might be a safe and effective revertant, and can be applied in the treatment of refractory and relapsed acute leukemia.

ATP Binding Cassette Transporter, Subfamily B↗
PubMed1997

[One Chinese case of F V Leiden mutation associated with APC resistance].

OBJECTIVE: To investigate the Factor V Leiden mutation associated with activated protein C resistance (APCR) in Chinese. METHODS: Twenty-eight normal individuals and 18 patients with thrombotic diseases were studied by APC-APTT, PCR followed by Mnl I restriction enzyme analysis, PCR-SSP, and DNA sequence analysis. RESULTS: In one normal individual of Chinese origin, the APC sensitivity ratio (APC-SR) was found to be significantly lower than that in other normal controls. This individual was identified to be heterozygous for F V Leiden mutation (Arg506 --> Gln). The APC resistance was found in 3 other cases of thrombotic diseases, but with no F V Leiden mutation. CONCLUSION: This is the first case of F V Leiden mutation associated with APC resistance reported in Chinese. It is noteworthy whether other gene defects are associated with APC resistance in Chinese and in thrombotic diseases patients.

Activated Protein C Resistance↗
PubMed1997

[The determination of enantiomeric purity for 1,1'-binaphthyl-2,2'-diol by high performance liquid chromatography].

In the past few years, much attention has been focused on the studies of the chirality recognition properties of chiral crown ether hosts containing the binaphthyl unit. The application of chiral 1,1'-binaphthyl-2,2'-diol (1) in asymmetric synthesis has been proved fruitful. Consequently, the preparation of optically active binaphthol and the determination of its enantiomeric purity is of current interest. In this paper, an efficient HPLC method for determination of enantiomeric purity of 1,1'-binaphthyl-2,2'-diol (1) through formation of a couple of diastereomers, (R)-1,1'-binaphthyl-2,2'-diyl-N-(S)-(alpha-methylbenzyl) phosphoramidate (R,S)-2 and (S)-1,1'-binaphthyl-2,2'-diyl-N-(S)-(alpha-methylbenzyl)phosphoramidate (S,S)-2, is described by using Micropak Si-5 column, petroleum and ethanol (7:3, V/V) as eluate and UV detector (lambda = 300nm). The method is convenient, rapid and accurate. The accuracy was between 98.6%-101.6%, and the average deviation was 1.01%.

Chromatography, High Pressure Liquid↗
PubMed1997

[The determination of enantiomeric purity for ibuprofen by high performance liquid chromatography].

Ibuprofen is an excellent anti inflammatory and analgesic drug. It possesses a chiral carbon atom in its molecule. For the two enantiomers, only the S(+)-isomer is highly active, whereas the R(-)-isomer has very low activity. S-isomer can be isolated by resolution from its racemoid and the R-isomer can be racemized under basic condition. Consequently it is highly important to determine its enantiomeric purity. In this paper, an efficient HPLC method for determination of enantiomeric purity for ibuprofen (1) through the formation of a couple of diastereomers, N-(S)-(alpha-methylbenzyl)-alpha-methyl-4-(alpha-methylpropyl)benzeneacetic amide [R,S-(2)], and (S)-(alpha-methylbenzyl)-alpha-methyl-4-(2-methyl-propyl)benzeneacetic amide [S,S-(2)], was developed using Micropak Si-5 column, petroleum ether and ethyl ether (1:1 volume) as eluate and UV detector (lambda = 300 nm). The method is convenient, rapid and accurate. The accuracy was between 99.71%-100.25%, and the average deviation was 0.064%.

Analgesics, Non-Narcotic↗
PubMed1997

[Syntheses and spectra of Mn(III)-chlorophyll-a and Mn(II)-chlorophyll-a].

Manganese(III)-chlorophyll-a [Mn(III)-Chl-a] was synthesized by the reaction of pheophytin-a and manganese(II) acetate and separated by HPCL. Manganese(II)-chlorophyll-a [Mn(II)-Chl-a] was acquired from Mn(III)-chl-a reduced by sodium hydrosulfite (Na2S2O4) in acetone-water. Because Mn(II)-Chl-a is oxidized very easily in the air, Mn (II)-Chl-a was kept under a nitrogen atmosphere and reductant during the spectroscopic measurements. Elemental analysis, absorption and FT-IR spectra proved that the metal Mn-substituted Mg of chlorophyll-a has been successfully performed and possible structure of new complexes was also given. Their formulae are [Mn(II) (chlorophyll-a)] and [Mn(III) (chlorphyll-a) (CH3COO)-(H2O)] respectively.

Chlorophyll↗
PubMed1997

[FT-IR characterization of extracted organic phase containing D2EHPA-lanthanide complexes and effects of adding DMHPA].

FT-IR spectroscopy was used to characterize the extracted organic phase of di (2-ethylhexyl) phosphoric acid-n-heptane containing lanthanide ions Ln3+ (Ln: Y, Pr, Nd, Eu ). It was found that the coordination interaction of heavy lanthanide ions with D2EHPA is stronger than that of light lanthanide ions, and saponification percentage of D2EHPA affects both the absorption frequency and the intensity of P=O bond in the extracted organic phase. Furthermore, the addition of di (1-methylheptyl) phosphoric acid to the D2EHPA extraction system leads to the variation of both peak position and intensity of P=O bond.

English Abstract↗
PubMed1997

[Fluorescence studies on the mixed solid complexes of europium-terbium-1, 10-phenanthroline-phthalate systems].

The 1, 10-phenanthroline-phthalate complexes of europium and terbium have been synthesized. Two series of mixed complexes, mechanical ground complexes (series 1) and chemical synthesized with mixed EuCl3 and TbCl3 solutions (series 2), have been also prepared. Fluorescence studies on all of the samples were performed. The results of their fluorescence spectra excited by 365nm UV-light showed that there are interactions between europium ions and terbium ions in these two kinds of mixed complexes. Their fluorescence intensities strongly changed especially for chemical synthesized mixed complexes, in which the fluorescence intensities of europium ions were greatly sensitized by terbium ions and those of terbium ions were strongly quenched by europium ions. But the peak positions of their emission bands did not shift obviously. The structure of these complexes have been characterized by FT-IR spectra. The results suggested that no free COOH groups exist and all of the nitrogen atoms of 1, 10-phenanthroline molecules coordinate to rare earth ions in all of these complexes.

English Abstract↗
PubMed1997

[Molfig, a software for displaying the structure and vibration of molecule].

A Molfig software has been developed for displaying the structure and vibrational mode of molecule in our lab. Various functions and a friendly interface are equipped in the software. The testing results showed that the software may enhance our understanding of the relationship between the vibrational behavior and the structure of molecules.

English Abstract↗
PubMed1997

[Fluorescence and FT-IR spectroscopic studies on the mixed solid complexes of europium and terbium phthalate].

In this investigation, the fluorescence and FT-IR spectroscopic studies on synthesized Eu-Tb phthalate complexes and mixed solid complexes of europium and terbium phthalates were perfomed. The experimental results of the emission spectra excited by 365nm UV-light showed that the emission peak positions of Eu ( III ) [or Tb ( III )] wer shifted slightly due to the interaction between Tb ( III )and Eu ( III ) ions. However, the fluorescence intensities of one rare eath ion Eu ( III ) [or Tb (III )] were strongly influenced by the other. FT-IR spectra indicated that the coordination structures of carboxyl groups, both in mechanically mixed and synthesized solid complexes, were also changed. These results suggested that there are interactions between Eu ( III ) and Tb ( III ) ions in their mixed complexes.

English Abstract↗
PubMed1997

[Curvefit, an overlapping bands resolving software for IR spectra].

A Curvefit software has been developed for resolving the overlapping band of the vibartional spectra in our lab . Various functions and a friendly interface are equipped in the software. The testing results showed that both the speed of the calculation and the reliability of the final results are satisfactory.

English Abstract↗
PubMed1997

Activation of extracellular signal-regulated kinase (ERK) by mitogenic stimuli is repressed in v-Src-transformed cells.

Stimulation of mitogenic signaling pathways results in transient activation of the extracellular signal-regulated kinase (ERK) subfamily of mitogen-activated protein kinases (MAPK) in normal cells. We demonstrate here that activation of ERKs in response to serum or phorbol ester stimulation was markedly repressed in three different rodent fibroblast cell lines stably transformed by v-Src. Activation of the MAPK/ERK kinase (MEK) was also repressed in v-Src-transformed cells, indicating that the repression occurs upstream of ERK. Consistent with repression occurring predominantly at the level of MEK, the phosphatase inhibitor orthovanadate could restore ERK activation to a limited extent in some but not all v-Src-transformed cell lines. A similar repression of ERK activation was observed in v-Ras- and v-Raf-transformed cells. In addition, ERK activity was not constitutively elevated in exponentially growing cells transformed by v-Src, v-Ras, or v-Raf as compared with normal cells. These results establish that the ERK activation pathway is repressed in rodent fibroblasts stably transformed by viral oncoproteins that chronically stimulate receptor tyrosine kinase signaling pathways. Furthermore, our findings suggest that elevated ERK activity above basal levels is not required for maintaining cell transformation by these oncoproteins. Taken together, these results indicate that ERK signaling pathways are subject to negative feedback regulation upstream of ERK as a consequence of oncogenic transformation.

3T3 Cells↗
PubMed1997

Comparison of hypolipidemic effect of refined konjac meal with several common dietary fibers and their mechanisms of action.

The effects of RKM in comparison with pectin, algin and agar on lipid levels in serum and liver and on liver histopathology in rats were studied. In addition, the effects of all the tested materials on the composition and output of fecal bile acid were observed. All four kinds of dietary fiber were given at a level of 5% of diet to young male rats of Wistar strain fed on a lipid-rich diet containing 5% lard, 1% cholesterol and 0.25% cholate. All the dietary fibers tested have similar effects on serum lipid composition. In all groups, these substances prevented increases in total cholesterol in fasting serum, but the level of triglyceride was unchanged. The concentrations of total cholesterol and triglyceride in the liver were lower in the RKM group than in the control group and the other three groups. Hepatic histopathological examination also showed the most significant lipotropic effect in the RKM group. The daily output of fecal bile acids (CDCA + GDCA) was significantly increased in the four experimental groups than in the normal group and the control group. The increase of CDCA was more significant than GDCA, suggesting that the increase of fecal bile acids, especially CDCA, may be one of the mechanisms by which RKM and the other three dietary fibers exerts a hypocholesterolemic effect.

Agar↗
PubMed1997

Analysis of FcgammaRII gene polymorphisms in Wegener's granulomatosis.

Fcgamma receptors (FcgammaRs) are potent initiators of proinflammatory reactions and tissue injury programs through the oxidative burst, degranulation and the production of a variety of proinflammatory cytokines. Direct experimental evidence indicates that translocation of ANCA target from intracellular granules to the neutrophil membrane and subsequent binding of ANCA enables FcgammaR-mediated neutrophil activation. In the presence of ANCA, these data provide a framework from which to understand the importance of ANCA class, subclass, and titer in Wegener's granulomatosis and other ANCA-positive vasculitides. The well-characterized and functionally important alleles of neutrophil FcgammaR (FcgammaRIIa-H131/R131 and FcgammaRIIIb-NA1/NA2) are possible inheritable genetic elements that may alter disease severity and/or phenotype.

Alleles↗
PubMed1997

Radioimmunoimaging of arterial and venous thrombi in canine model using 99mTc labeled monoclonal antifibrin antibody.

OBJECTIVE: To evaluate the usefulness of 99mTc labelled monoclonal antifibrin antibody SZ-63 for the detection of vascular thrombi, and to investigate the feasibility of thrombus imaging 99mTc-SZ-63. METHODS: The monoclonal antibody SZ-63 (Mab SZ-63), which reacts with D-dimer, XLFN and fibrin monomer was produced and labelled with 99mTc using pretinning procedure. After that, the femoral arterial or venous thrombus model was prepared in dogs and injected with 99mTc-SZ-63 intravenously. Both arterial and venous thrombus models were imaged. RESULTS: Both the arterial and venous thrombi were clearly visible within 2.5 hours after injection of 99mTc-SZ-63. Quantitative imaging analysis showed that the ratios between the thrombus and the opposite vessel increased with time extension. The ratios of thrombus to blood or surrounding muscle were 2. 56 +/- 0.83 and 13.40 +/- 5.10 for arterial thrombi and 3.34 +/- 1.06 and 22.40 +/- 6.40 for venous thrombi after the canines were killed. CONCLUSION: 99mTc-SZ-63 is a useful imaging agent for thrombus detection in vivo.

Animals↗