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Biomedical subjects

J Wu

Publications and source records attributed to J Wu.

At least 685 records · Page 38Linked to original sources
PubMed1999

[The SEM observation of brain tissues and vascular corrosion cast of closed diffuse brain injuries].

The morphologic changes of the closed injured brain of rats were observed by SEM. The rats either died immediately after conclusive injuries or were killed after 5 minutes to 5 days after injuries. The main changes were as follows: the diffuse disorder, twist, wave-like distortion and break of neuron fibers; axonal swelling; formation of axonal retraction balls; stripping and denotation of myelin sheath The ball-like swelling of neuron, break of neuron membrane and vascular wall, and microthrombus formations were also observed. These damages worsened with prolongation of surviving time of the rats. The axonal retraction ball appeared 8 hours after the injury and was approximately 3-5 cm in diameter, and developed to 7-8 cm after 3-5 days. It is observed that frontal lobe, cerebellum and brain stem were severely damaged.

Animals↗
PubMed1999

[MBP content in serum after closed diffuse cranial injury in rats].

The MBP content change in serum was observed by ELISA in rats with experimental closed diffuse cranial injury. The MBP content was 6.1633 +/- 1.5301 ng/ml (X +/- S) in the normal group, 11.3818 +/- 2.6574 ng/ml in the first group died immediately after injury, 10.8319 +/- 2.3135 ng/ml in the second group of 15 min after injury. This increased level of MBP was lasting in the following 3 days and returned to normal at the 4th and 5th day after injury. The difference of the MBP levels between the groups after injury and that in the normal group is significant (P < 0.01).

Animals↗
PubMed1999

[Allele and genotype frequency distribution of D19S400 locus in several populations].

Using polymerase chain reaction and PAG electrophoresis, D19S400 Locus was investigated in the populations of Chinese, Germany, Slovakian, and American Black Population. 620 samples collected from the four populations were tested and a total of 11 alleles (*7 to *17) and 47 genotypes were found. The heterozygosity was observed between 0.78 and 0.88, and the discriminating power was between 0.9385 and 0.9664. The distributions of genotypes in the four populations were in accordance with Hardy-Weinberg equilibrium. Significant differences were observed in the distribution of allele frequencies among the three major racial populations (Mongoloid, Caucasian, Negroid). According to the results obtained in this study, D19S400 locus is a robust STR for forensic and genetic purposes.

Alleles↗
PubMed1999

[Effects of hexamethylene bisacetamide on P53 protein expression of MEC-1 cell line and cell differentiation].

OBJECTIVE: To investigate the relationship between the differentiation of the mucoepidermoid carcinoma cell line MEC-1 induced by HMBA and the expression of P53 protein. METHODS: Effects of HMBA on the growth of MEC-1 cells in vitro were measured with MTT colorimetric assay, and the content of DNA in cells was assayed by using Feulgen's staining. The P53 protein expression of MEC-1 cells was detected with ABC immunohistochemistry with anti-mutant P53 protein antibody, and the distribution of cells in different differentiation phase was determined by flow cytometry. RESULTS: HMBA inhibited the growth of MEC-1 cells in a dose-dependent and time-dependent manner, and HMBA-treated MEC-1 cells were arrested in the G1 phase and had a lower content of DNA and a lower level of P53 protein compared with the control group. CONCLUSION: The differentiation of MEC-1 cells induced by HMBA may be associated with the regulation of HMBA on the P53 protein expression and the cell differentiation cycle.

Acetamides↗
PubMed1999

[Cartilage matrix synthetic ability of rabbit articular chondrocytes cultured in vitro].

OBJECTIVE: To observe the ability of matrix synthesis of rabbit articular chondrocytes cultured in vitro. METHODS: Rabbit articular chondrocytes were acquired by digestion of 0.1% type II collagenase and cultured in vitro, then cell morphology and ultrastructure were observed with phase-contrast microscope and scanning electronic microscope. With continuous culturing of chondrocytes in DMEM medium containing 15% FBS, synthesis of cartilage matrix was observed by using microscope and safranine-O staining. RESULTS: The cultured chondrocytes were polygonal cells. There were many rough endoplasmic reticula and mitochondria in cytoplasm, and a lot of secretory vesicles under cell membrane and in the cytoplasm. When cultured for 10 days, some small and white nodules were formed on the bottom of the culture dishes, and volcanic-mouth-like structures were formed when cultured for 20 days. Both these nodules and structures contained GAG-positive substances were demonstrated by safranine-O staining. CONCLUSION: Chondrocytes can produce matrix and cartilage-like tissue in vitro, so it is feasible to produce cartilage by culturing chondrocytes in vitro.

Animals↗
PubMed1999

[Inhibitory Effects of Etoposide Combined with 8-methoxypsoral en on Highly Metastatic Human Mucoepidermoid Carcinoma Cells].

OBJECTIVE: To study the inhibitory effects of Etoposide (VP16) combined with 8-methoxypsoralen (8-MOP) on human highly metastatic mucoepidermoid carcinoma cells (Mc3). METHODS: Mc3 cells were exposed to the drugs and their combinations at various concentrations. The inhibitory effects were tested with microculture tetrazolium colorimetric assay (MTT assay) and cologenic assay. RESULTS: The IC50 values of VP16 and 8-MOP were 1625. 25 ng/ml and 750000 ng/ml respectively, the CI50 of the combination at 100320 and 1000 ng/ml of VP16 with 8-MOP were 0.350, 0.599 and 0.880 respectively. CONCLUSION: The data indicate that combination of VP16 and 8-MOP is synergic in the inhibition of Mc3 cell growth.

Carcinoma, Mucoepidermoid↗
PubMed1999

[Analyses on structural and physicochemical properties of collagen hemostatic sponge].

The ultraviolet spectrum and aminoacid content of collagen hemostatic sponge prepared from bovine tendon were analyzed, and the struture and composition of collagen spoge were confirmed. Physicochemical properties measurements showed that collagen hemostatic sponge had excellently stable quality. It was concluded that the technology for preparing collagen hemostatic sponge was reasonable and reliable.

Collagen↗
PubMed1999

[Studies on biosorption of Pb2+ by Phanerochaete chrysosporium].

The biosorption of Pb2+ from solution by Phanerochaete chrysosporium was studied. The effects on biosorption capacity of pH, Pb2+ concentration in solution, co-ion and temperature, time have been examined. The adsorption capacity was compared among the biomass harvested at various growth stages. Pretreatment of biomass by NaOH solution improved its adsorption capacity. The uptake could reach 108.4 mg/g at optimal conditions of biosorption using pretreated biomass.

Absorption↗
PubMed1999

[Species identification of Mycobacterium tuberculosis with insertion elements].

The Insertion Sequence(IS) element IS6110 and IS1081 of M. tuberculosis complex were used as template to prepare probes for typing strains by means of restriction fragment length polymorphisms (RFLP). Chromosomal DNA of M. tuberculosis H37Ra, H37Rv, M. bovis digested with EcoR I, Pst I, Sal I, BamH I, Pvu II was subjected to Southern Blot analysis With labeled 317bp from IS6110 and 248 bp from IS1081. The results indicated that for M. tuberculosis complex, IS1081 cannot be used to type strains, IS6110 can be used to distinguish strains into broad groups and is an excellent epidemiological tool for studying outbreaks. An investigation of forty-six M. tuberculosis isolates by IS6110 RFLP revealed that M. tuberculosis strains not only are of highly polymorphic, but also are presentin multiple copies ranging from 7 to 18 copies.

DNA Probes↗
PubMed1999

[Pathogenesis and clinical classification of the malignant glaucoma].

PURPOSE: To study the pathogenesis of the malignant glaucoma and the basis for the clinical classification of malignant glaucoma. METHODS: Twelve eyes with malignant glaucoma were examed by ultrasound biomicroscopy (UBM), type A and type B ocular ultrasounographer and other clinical ophthalmic tests and diagnostic therapy. The ocular anatomic structures of all 12 eyes were compared with those of the fellow eyes. RESULTS: Ciliary block were confirmed in four of the twelve eyes (33.3%) with malignant glaucoma while the narrow and small anterior segment were found in the fellow eyes by UBM. Iris lens disphragm anterior displacement were found in the other eight of the twelve eyes (76.6%) and their ciliary bodies were deformed passively. The ciliary bodies and anterior segment of the fellow eyes of these eight eyes were anatomically normal. Diagnostic surgery was performed in seven of the twelve eyes and six cases with fluid existing in the vitreous cavity were identified. CONCLUSION: According to our study, we suggest to classify malignant glaucoma into two tyges. One is ciliary block, which caused by ciliary block and concerned with the narrow and small structure of the anterior segment of eye. The other is lens iris block, which caused by iris lens diaphragm anterior displacement. Both types have the same pathophysiologic characteristics, such as, shallow anterior chamber, posterior chamber disappearance and aqueous humor misdirection to the vitreous cavity. But their pathogengesis may not be completely same.

Adult↗
PubMed1999

[Studies on decomposed crop residues by FTIR differential analysis].

The decomposing process of corn leaf residues (CLR) was studied by FTIR differential analysis, and the differential spectra were compared with normal spectra. The result showed that the purification process to remove inorganic matters from decomposed CLR could be omitted when differential analysis is used, and the differential spectra were clear and distinct. As far as the studies of decomposed crop residues, the FTIR differential analysis was a convenient and forthright method.

Spectroscopy, Fourier Transform Infrared↗
PubMed1999

[FTIR and FT-Raman studies on interactions between water and surfactants in water/KDEHP (75%)-HDEHP (25%)/n-HEPTANE microemulsion systems].

The conformation of the hydrocarbon chains in water/KDEHP(75%)-HDEHP(25%)/n-HEPTANE microemulsion systems was studied by FT-Raman spectroscopy. The increase in the intensity ratio Ir (I2937/I2875) showed trans to gauche transformation. The hydration of the polar heads in microemulsions was investigated by FT-IR spectroscopy. Some probable structures of KDEHP and HDEHP in microemulsions were proposed.

Emulsions↗
PubMed1999

[SERS of bilirubin and its complexes].

SERS spectra of bilirubin and its complexes were determined in Ag sol by the technique of the connection between NIR-FT-Raman and SERS. The spectra showed that this kind of biological complexes, which is closely related to gallstones, differ in coordination pattens and adsorptive orientation as well. The reason why the black-pigment gallstone exhibits that peculiar dark color was also given from the coordination-chemistry point of view.

Bilirubin↗
PubMed1999

[Water structure in water/KDEHP-HDEHP/n-Heptane microemulsion by FTIR spectroscopy].

The structure of water in microemulsion is one of the basic subjects in the field of surface science. FTIR spectroscopy is considered as a powerful tool in the study on water structure. In this paper, we investigated water structure in the water/KDEHP (potassium bis (2-ethylhexyl) phosphate) -HDEHP/n-Heptane system. By using the Fourier self-deconvolution and curve-fitting method, the OH stretching band of water in the KDEHP-HDEHP microemulsion was resolved into four subpeaks which were tentatively assigned to absorbances of four different components of water. In order to explain the variations of peak positions of subpeaks with water content some probable hydration models of surfactants were proposed.

English Abstract↗
PubMed1999

[Study on the Co(DC)2-NaDC mixed micelle system].

Eight coordinated complex samples of CoCl2-NaDC were obtained,using various concentration and initial molar ratio of CoCl2 and NaDC. They exhibited distinct appearances and characters. Their different structures and components were investigated by FTIR spectroscopy, X-ray diffraction analysis and ICP analysis. We can give the following conclusions: (1) when the concentration of NaDC is smaller than C.M.C, Co2+ ions react with mono-molecular NaDC and the component of the pink wadding-like resultant is Co(DC)2 x 3H2O. (2) When the concentration of NaDC is larger than C.M.C, and the concentration of CoCl2 is higher (0.5 mol/L), Co2+ ions destroy NaDC micelles, and the component of the pink wadding-like resultant is also Co(DC)2 x 3H2O. (3) When the concentration of NaDC is larger than C.M.C, and the concentration of CoCl2 is lower (0.1 mol/L or more lower), Co(DC)2 and NaDC may form mixed micelles, and some of NaDC micelles connect with each other through the Co2+ bridges to produce complicate Co(DC)2-NaDC complex with gel character and macromolecular network structure. In human body,the concentration of metal ions is usually lower and the concentration of NaDC is larger than C.M.C, So the third kind is suggested as an ideal model of the interaction between Co2+ ions and NaDC in vivo.

Bile Acids and Salts↗
PubMed1999

[Study on the human serums by absorption spectra].

The absorption spectra of normal human and cancer patient serums were measured, and those of human serum after adding some cancer cells were also measured. The results showed some difference in absorbance among the three kinds of serums. Some useful results were obtained.

Humans↗
PubMed1999

[Comparative studies on five pretreatment methods in the determination of elements in plant standard sample by ICP-AES].

Direct determination of the contents of 19 major or trace elements: K, Na, Ca, Mg, Si, Al, Fe, P, Sr, Ti, Mn, Zn, Pb, B, Ba, Cu, Li, V and Ni in plant samples by ICP-AES are reported in this paper. The solution of plant standard sample GBW07603 was prepared by five pretreatment methods: dry-ashing, HNO3 + H2SO4 + HClO4, H2SO4 + H2O, HNO3 + H2SO4 + HClO4 + HF and ashing + NaOH method. Suitable pretreatment methods were found for the determination of the elements by comparing standard deviations and relative errors of the results, thus providing a scientific basis for the selection of suitable pretreatment of chemical element analysis in plants.

Chemistry Techniques, Analytical↗