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Biomedical subjects

J Wu

Publications and source records attributed to J Wu.

At least 847 records · Page 47Linked to original sources
PubMed1998

[Detection of HFRSV in Eulaelaps shanghaiensis and Ornithonyssus bacoti by using in situ hybridization].

AIM: To provide molecular biological evidence of transmission of hemorrhogic fever with renal syndrome virus (HFRSV) by gamasid mites, Eulaelaps shanghaiensis and Ornithonyssus bacoti. METHODS: Frozen sections of the gamasid mites 10 days and more than 100 days after biting suckling mice inoculated with HFRSV were in situ hybridized with dig-labelled HFRSV cDNA probes. RESULTS: RNA was detected in frozen sections of Eulaelaps shanghaiensis, after biting suckling mice inoculated with Hantaan (76-118) and Seoul (UR) virus, respectively. Most of the fine granules of the virus RNA were located in the nuclei, cytoplasm and nuclear membrane of cells of brain cortex, caeca and genitalia of the mites. In situ hybridization results showed that 17 of 31 mites in Hantaan group and 10 of 23 mites in Seoul group were positive. The virus RNA was still detected in tissues of the mites on d132 for Hantaan group and on d102 for Seoul group after infection, respectively. Among 20 Ornithonyssus bacoti detected 12 were positive on d10 after biting suckling mice inoculated with Hantaan virus, and the virus RNA was mainly found in the cells of genitalia (Figs. 1-13). CONCLUSION: Both Eulaelaps shanghaiensis and Ornithonyssus bacoti could be infected with HFRSV by biting HFRSV-positive mice. E. shanghaiensis could be infected with both Hantaan and Seoul virus, and the two types of HFRSV were found to be maintained in the mites for 132 days and 102 days, respectively. These confirmed that E. shanghaiensis and O. bacoti are suitable vectors and reservoirs of both Hantaan and Seoul virus and might play an important role in the cross transmission of the two types of HFRSV.

Animals↗
PubMed1998

[Studies on the experimental transmission of Rattus-borne Hantavirus by Ornithonyssus bacoti].

AIM: To demonstrate the role of rat mite (Ornithonyssus bacoti) in the transmission of Rattus-borne hemorrhagic fever with renal syndrome (HFRS). METHODS: In the transmission experiments, about 100 O. bacoti per pool were isolated and placed in a jar, unfed for 4 d at 23 +/- 1 degrees C. Suckling Wistar rats inoculated with Hantavirus strain Z45 or Seoul virus strain UR were placed in each jar for free attack by the mites for 12 hours. After 14 d the normal suckling Wistar rats were bitten by the mites. Fifteen days later, the lung tissues and sera of the infected rats were collected and detected for Hantaviral antigen by indirect fluorescent antibody technique (IFAT). For demonstration of the infection of O. bacti with Rattus-borne Hantavirus PCR technique was applied to detect Rattus-borne Hantaviral RNA. RESULTS: Sukling Wistar rats inoculted Hantavirus strain Z45 or Seoul virus strain UR were bitten by O. bacoti and then these mites were fed on 4 and 5 of normal suckling rats in each jar, respectively. The antigens of Hantavirus strain Z45 were positive in all the lungs of the normal rats bitten by the mites, the sera titers of the rats were from 1:10 to 1:40. The antigens were positive in 3 of the 4 rats, the sera titers were from 1:20 to 1:40. Both of the viruses could be maintained in O. bacoti for 22 days. The blocking test showed when 1:30 Hantavirus immunosera were exposed to the lung samples and then reacted with the sera from the patients with HFRS, all the specific fluorescence reactions of the samples were blocked, whereas the control group including the normal rat lung tissues and sera were all negative (Fig. 1). CONCLUSION: O. bacoti might play a role as the vector of HFRS and a reservoir host as well.

Animals↗
PubMed1998

[Inhibitory effects of 8-methoxypsoralen combining with all trans retinoic acid on oral squamous cancer cell lines].

To study the inhibitory effects of 8-methoxypsoralen (8-MOP) combining with all trans retinoic acid (RA) on tongue cancer cell line Tca8113 and gingiva cancer cell line Ca9-22, MTT assay (tetrazolium-based colormetric assay) was applied and the changes in morphology were observed with the inverted microscope. The results showed that with 30% growth inhibition of the cell lines, the Combination Indexes (CI30) of the two drugs were no more than 0.82, and with 50% growth inhibition, the Combination Index (CI50) were from 0.9 to 0.95, which indicated synergic combination effects of the two drugs against the two oral squamous cancer cell lines. Apoptosis-body-like structures were observed in the cells treated with RA, 8-MOP, or the combination of RA with 8-MOP. Whether combination of the two drugs at appropriate concentrations has clinical value needs to be investigated.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1998

[Chemical constituents of Epimedium acuminatum Franch. (II)].

OBJECTIVE: To study the components of roots of Epimedium acuminatum. METHOD: Column chromatography was employed for the isolation. The isolated compounds were elucidated by UV, IR, FAB-MS, 1HNMR and 13CNMR analysis. RESULT: Four constituents were obtained and elucidated as epimedoside A(V), diphylloside B(VI), epimedin C(VII) and ikarisoside C(VIII). CONCLUSION: Four constituents are all flavonol glycosides, of which VI, VII and VIII were separated from this plant for the first time.

Disaccharides↗
PubMed1998

[Expression, purification and characterization of recombinant human cyclophilin A].

Plasmid-derived expression of the human CyPA in E. coli would make it possible to obtain ample protein quantities and to avoid difficult task of obtaining human tissues for protein purification. The cDNA encoding human CyPA from MT4 lymph cell line has been cloned and an expression vector (pET11/CyPA) has been constructed under control of the T7 promoter for efficient expression in E. coli. The recombinant CyPA is produced at 41% of total soluble cell protein, and showed the peptidyl-prodyl cis-trans isomerase activity.

Cell Line↗
PubMed1998

[Collagen sponge and its hemostatic properties].

Soluble collagen was extracted from bovine tendon in acid solution. Collagen sponge hemostatics were prepared by means of lyophibization. The amino acid and UV spectrum analyses were made to confirm the composition of the soluble collagen. The results of experiments on rabbits indicated the collagen sponge prepared in the authors' lab had excellent hemostatic and adhesive properties in vivo surgical tests.

Amino Acids↗
PubMed1998

[The habit of flowering and fruiting of Scaphium lychnophorum].

The flowering and fruiting are much different between the trees of Scaphium lychnophorum which were introduced in Jinghong. The trees have on-year of fruiting once 3-4 years and off-year continue 2-3 years. In Jinghong, the low temperature in the early flowering period is one factor among the main factors effecting flowering and fruiting of trees. The trees which vegetative grow flush and which grow on the place in a poor sunlight are effected their flowering and fruiting, too.

Flowers↗
PubMed1998

[FTIR study on structure of pearl and nacre of mollusk shell].

Pearl and nacre of mollusk shell (Hyriopsis cumingii) were studied with high resolution Fourier transformation infrared spectroscopy (FTIR) and X-ray diffraction (XRD). The results of X-ray diffraction indicate that the samples are still aragonite after thermal treatment at 160 degrees C for 5hr, however, the significant variations of peak position and band width of FTIR spectra reveal the interaction between organic matrix and inorganic crystal in biomineralized materials. The variations of spectra were studied by a curve-fitting algorithm and the band related to the interaction is revealed.

Animals↗
PubMed1998

[Spectroscopic characterization of a new terbium complex with red fluorescence].

Usually, the emission spectra of terbium complexes exhibit 490 nm, 545 nm bands (green color) under the excitation of UV light, which is ascribed to the two 5D4 - 7F6, 5D4 - 7F5 transition. In this report, pink red fluorescence under the excitation of 300-370nm UV light is observed for a new 1, 10-phenanthroline-2-naphthoate complex of terbium. The fluorescence, FT-IR, ICP and X-ray fluorescence analysis were performed. The results showed that under the perturbation of the ligands field, the probability of 5D4 - 7F3 transition of terbium ion was greatly enhanced, while the probability of 5D4 - 7F5 transition was greatly decreased in the complex. Therefore, pink-red fluorescence was observed for the title complex.

English Abstract↗
PubMed1998

[Investigation on the luminescence properties of Er ions in Er-doped sol-gel silica glasses].

Er-doped sol-gel silica glasses which have room temperature photoluminescence at 1.54 microm and doped concentration of 10(20)/cm(3) have been prepared. The examination results Indicated: (1) PL spectrum has largest intensity at the 0.5W% doped concentration; (2) the intensity of PL decreased 74%, when the temperature raised form 4K to 300K; (3) The Er ion and O ions formed complexes with coordinated numbers of 8 or 9.

English Abstract↗
PubMed1998

[Comparative study on the hydration of phosphate group in H2O/NaDEHP/n-heptane and H2O-TBP systems by FT-IR].

The hydrations of phosphate group in both tributyl phosphate (TBP)-H2O system and water/NaDEHP/n-heptane reverse micellar system have been studied using Fourier transform infrared spectroscopy (FT-IR). Water content (W0 = [H2O]/[TBP]) in TBP solutions was measured quantitatively using FT-IR. In water/NaDEHP/n-heptane reverse micellar system, the stretching frequencies of phosphate group shifted from 1229 to 1200cm(-1) when water content increased from 1 to 25. For TBP-H2O system, P=O stretching band varied from 1281.33 to 1263cm(-1) with the increasing water content (from 0.33 to 1.55). P=O stretching bands in TBP-H2O system were also found to split into two peaks located around 1283 and 1260cm(-1) after the bands were resolved by curve-fitting. All these variations are attributed to the hydration of phosphate in the two systems.

English Abstract↗
PubMed1998

[FT-IR study on the solid-state reaction of bilirubin on BaF2].

Bilirubinate complexes are the main component of pigment gallstones and the recent researches suggested that bilirubin free radical plays a role in some biological processes. In this paper the solid-state reaction of bilirubin on BaF2 was examined by FT-IR. The solid-state reaction was produced by grinding the crystalline bilirubin and single crystals BaF2 together in an agate mortar. From the results the free radical mechanism is suggested in the solid-state reaction of bilirubin on BaF2. The replacement of H on NH of pyrrole by Ba2+ was prior to that of H on COOH. The structure of the resultant complex from the solid-state reaction is different compared with that from the liquid-state reaction.

Barium Compounds↗
PubMed1998

[Infrared spectroscopy application in soil organic matter].

As an important method to study the constitution and properties of macromolecular organic compounds, the infrared spectroscopy has been more and more widely taken in the researches of soil organic matters (SOM). Especially,the application of FTIR and the combined uses of FTIR with chromatogram etc. have made the researches of SOM get a great progress in many aspects. In this paper, the infrared spectroscopy applications were reviewed in SOM. It includes the following contents: the methods to study SOM by IR, studies on the constitution of soil humic substances (SHS), extraction of SOM and classification of SHS, decomposition, transformation and humification of organic matters, the differences of SOM in different situations, the interactions of SHS with metais, clay minerals and other organics in soil.

Humic Substances↗
PubMed1998

[FTIR study on the normal and tumor gastrointestinal tissues].

Series of cancer tissues and corresponding normal tissues of gastrointestinal tract (stomach, colon, esophagus) were studied by FTIR technique and the results showed the analogy of the spectra for the cancer tissues, while the spectra of normal tissues can be classified into three kinds. The secondary structures of protein were obtained by using deconvolution and curve-fitting techniques with Amide I bands and the results showed that the contents of alpha -helix and beta-sheet are different between the normal and cancer tissues.

Connective Tissue↗
PubMed1998

Raman spectroscopy and fluorescence photon migration for breast cancer diagnosis and imaging.

We are developing optical methods based on near infrared Raman spectroscopy and fluorescence photon migration for diagnosis and localization of breast cancer. We demonstrate the ability of Raman spectroscopy to classify accurately normal, benign and malignant breast tissues, an important step in developing Raman spectroscopic needle probes as a tool for improving the accuracy of needle biopsy. We also show that photon migration imaging can be used to localize accurately small fluorescent objects imbedded in a thick turbid medium with realistic optical properties, thus demonstrating the potential of this technique for optical imaging.

Breast Neoplasms↗
PubMed1998

[Genetic polymorphism of inter-alpha-trypsin inhibitor in six Chinese populations].

OBJECTIVE: To understand the distribution of allele frequencies of inter-alpha-trypsin inhibitor(ITI) in Chinese populations. METHODS: The polymorphism of this protein in six Chinese populations was investigated using isoelectric focusing followed by immunoblotting technique. RESULTS: Three common alleles, ITI*1, ITI*2, and ITI*3 were observed in four populations, namely Han living in Jilin, Mongol in Hailaer, Tibetan in Lasa, and Bai in Dali respectively. In other two populations, Zhuang in Guangxi and Han in Guangdong, only ITI*1 and ITI*2 were observed. For these populations, the frequency of ITI*1 ranges from 0.5500 to 0.7525; that of ITI*2 from 0.2475 to 0.4322; and that of ITI*3 from 0.0034 to 0.0729. CONCLUSION: This study reveals that there is no parallel relationship between variation of allele frequencies and geographic differences.

Alpha-Globulins↗