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Biomedical subjects

Q Zhu

Publications and source records attributed to Q Zhu.

At least 163 records · Page 9Linked to original sources
PubMed1998

New cell surface marker of the rat floor plate and notochord.

Regionally expressed cell surface molecules are thought to mediate contact-dependent interactions that regulate pattern formation and axon pathfinding in the developing vertebrate central nervous system (CNS). We recently isolated monoclonal antibody (mAb) CARO 2 through a screen for positional markers in the developing rat CNS. Between embryonic day (E)11.5 and E13, mAb CARO 2 specifically labels both the floor plate and notochord in the developing spinal cord. In contrast to the distribution of several well-characterized ventral midline markers, mAb CARO 2 labeling is restricted to the apical portion of the floor plate and the outer surface of the notochord. The anterior limit of mAb CARO 2 immunoreactivity corresponds to the midbrain/hindbrain border. Floor plate labeling persists throughout embryogenesis, whereas notochord labeling is not detectable after E13. During later stages of embryonic development (E16-E20) apically restricted floor plate labeling is present only in the rostral spinal cord. In postnatal rats, mAb CARO immunoreactivity is not present in any region of the CNS. Immunoblot analyses show that mAb CARO 2 recognizes an epitope on a 28-kD protein that is enriched in the floor plate, transiently expressed during embryogenesis, and membrane-associated. Consistent with the latter result, mAb CARO 2 labels the surfaces of floor plate cells. These findings suggest that the CARO 2 antigen is a new cell surface marker of the floor plate and notochord which may participate in neural cell patterning and/or axon guidance in the developing rat spinal cord.

Animals↗
PubMed1998

Integrin expression in human dental pulp cells and their role in cell attachment on extracellular matrix proteins.

Integrins are a family of heterodimeric glycoproteins consisting of alpha and beta subunits that noncovalently interact to form cell surface adhesion receptors. The objective of this study was to identify integrins in human dental pulp cells and determine their role in human dental pulp cell attachment to the biological active molecules, laminin and fibronectin. Integrin expression was studied by immunoblot and immunoprecipitation using monoclonal integrin antibodies. The role of integrin in human dental pulp cell adhesion on laminin and fibronectin was determined by inhibition of cell adhesion with those antibodies. This study found human dental pulp cells expressed alpha 1, alpha 3, alpha 5, alpha 6, alpha v, and beta 1 integrin subunits. The adhesion of human dental pulp cells to laminin and fibronectin was not inhibited by monoclonal antibody to any subunit, except that anti-beta 1 antibody inhibited pulp cells adhesion on laminin. These data provide information for further studying the role of integrins in dental pulp cell biological function.

Cell Adhesion↗
PubMed1998

The role of integrin beta 1 in human dental pulp cell adhesion on laminin and fibronectin.

OBJECTIVE: This study is to identify the expression of integrin beta 1 in human dental pulp cells and the role of integrin beta 1 in pulp cell adhesion on extracellular matrix protein laminin and fibronectin. STUDY DESIGN: Immunoblot detection of integrin beta 1 in human pulp cells was with the use of monoclonal anti-beta 1 antibody. Dental pulp cell adhesion assay on extracellular matrix protein laminin and fibronectin and blocking cell adhesion was performed with monoclonal anti-beta 1 antibody. RESULT: Integrin beta 1 was identified in human dental pulp cells. Pulp cells adhered and spread on both laminin and fibronectin. Monoclonal anti-beta 1 antibody inhibited human dental pulp cells adhesion on laminin but not on fibronectin. CONCLUSIONS: Integrin beta 1 was expressed on human dental pulp cells and mediated cell adhesion on laminin. Human dental pulp cells also adhered on fibronectin but the adhesion was not regulated by beta 1 integrin.

Antibodies, Monoclonal↗
PubMed1998

Purification and characterization of the MUC1 mucin-type glycoprotein, epitectin, from human urine: structures of the major oligosaccharide alditols.

The MUC1 glycoprotein, epitectin, a component of the human bladder epithelium, was purified from human urine. Sedimentation equilibrium analysis and gel filtration using polysaccharide or protein standards revealed a polydisperse preparation with molecular weights ranging from about 0.9 to 1.3 x 10(6). This suggests that in the native state epitectin exists as aggregates of three or four monomer units of 350-400 kDa. Epitectin was found to have significant affinity to hexyl-, octyl- or phenyl agarose indicating that hydrophobic interactions and possibly carbohydrate-carbohydrate interactions may be responsible for the self-association. Chemical and enzymic deglycosylation of [125I]-labeled urine epitectin and metabolically labeled H.Ep.2 epitectin resulted in extremely polydisperse products. The buoyant densities of epitectin purified from urine and H.Ep.2 cells were found to be 1.39-1.40 g ml(-1), suggesting that the total carbohydrate content of these preparations is not significantly different. The O-linked saccharides of epitectin were fractionated by HPLC and analyzed by permethylation and FAB-MS. The neutral saccharides from both sources contain three common structures, namely Gal1 --> 3GalNAc, GlcNAc1 --> 6 (Gal1 --> 3) GalNAc and Gal1 --> 4GlcNAc --> 6 (Gal1 --> 3)GalNAc. The sialic acid of urine epitectin consisted entirely of N-acetylneuraminic acid. The two sources of epitectin, in vitro labeled on sialic acid, were found to have the same sialyl oligosaccharides but in different proportions. Metabolic labeling and N-glycanase susceptibility experiments firmly established the presence of N-linked saccharides in epitectin as minor components. The remarkable similarities in the total carbohydrate content, the carbohydrate composition and structures of saccharides between epitectin from urine, a non-malignant source, and H.Ep.2 cells is surprising in view of the prevailing view that MUC1 glycoproteins of cancer cells are underglycosylated compared to those produced by non-malignant cells.

Amino Acids↗
PubMed1998

[Ovarian follicular maldevelopment in infertile women].

OBJECTIVE: To study the manifestation and outcome of ovarian follicular maldevelopment (FM) in infertile women. METHODS: Among 296 infertile women, 80 cases with FM were taken as study group and 20 with normal ovulation as control. Serial B-ultrasonography, cervical mucus scoring, serum estradiol (E2) assay and laparoscopy, endometrium histology were monitored in both groups. RESULTS: The incidence of FM in infertile women was 27.0%, B-ultrasonography showed many small and obscure outlined follicles in the ovarian. The maximum and mean cervical mucus socres in FM group were < 9 and 7.3 +/- 1.8, significantly lower than those in control (> 10, 13.2 +/- 1.8) (P < 0.01). So were the midcycle serum E2 levels (300 +/- 100 pmol/L vs 900 +/- 400 pmol/L, P < 0.001). No stigma was found in two-third of FM patients and no corpus luteum in about one-third. Proliferative endometrium was shown in 34.0% of the FM group. CONCLUSION: (1) FM with an incidence of 27.0% might be an important cause of infertility. (2) FM results finally in follicular atresia or multiple immature luteinized follicles.

Adult↗
PubMed1998

[Evaluation of body surface ultrasonography in the diagnosis of diseases of abdominal segment esophagus and early-stage carcinoma].

OBJECTIVE: To investigate the possibility of detecting esophageal carcinoma and other lesions by body surface ultrasound (BSUS). METHODS: BSUS examinations of the abdominal segment of the esophagus in 797 subjects were undertaken. Wall thickness more than or equal to 6 mm, wall echo abnormality, and lumen morphologic changes were referred as the criteria of the disease. RESULTS: A visualization rate of 92% (n = 729) was obtained. 716 subjects without any esophageal diseases had a wall thickness of 4 mm or less; Of other 13, one patient had a wall thickness of 5 mm, 11 had 6 mm or more, and one had luminal cystic dilatation without wall thickening. In the 13 cases, the final pathological examination showed 5 cases of esophageal carcinoma (intramucosal, mucosal muscle, submucosal, proper musculature, and serosal patterns, respectively), 2 of metastatic lesion, one of leimyoma, 2 of edematous benign ulcer, one of diverticulum with polyp, and 2 of normal result. CONCLUSION: BSUS can not only detect the early-stage carcinoma, but also further demonstrate wall echo and pathologic changes inside and outside the wall. In the visualization of the submucosal tumor, it is advantage ous to barium examination and endoscopy. With its high sensitivity, simplicity, and non-intervention, BSUS can become a better screening method in everyday practice and in the area with high incidence of esophageal carcinoma.

Adult↗
PubMed1998

[Modified lipoproteins in atherosclerotic lesions of human aorta].

OBJECTIVE: To study the distribution patterns, amount, as well as the physical and chemical properties of malondialdehyde (MDA) and 4-hydroxynonenal (HNE) modified apolipoprotein B (apo B) in atherosclerotic lesions of human aorta. The distribution patterns of MDA and HNE modified apo B were also compared with those of lipoprotein(a) [LP(a)] and apo B. METHODS: Immunohistochemistry, electronic microscopy, immunoelectronic microscopic and biochemistry methods were used for qualitative and quantitative analysis. RESULTS: It was found that the distribution of MDA and HNE modified apo B coincided with Lp(a) and apo B in the extracellular matrix. While the distribution of MDA-apo B and HNE-apo B in foam cells appeared annular or particulate, similar to ceroids but different from that of Lp(a) or apo B. The physical and chemical properties of LDL from lesions on the intima were similar to those of in vitro modified LDL. In addition, a higher level of aldehyde modified LDL was extracted from the lesion areas than from normal intima. CONCLUSION: Oxidative modification of apo B containing lipoproteins is necessary for atherogenesis.

Aorta, Thoracic↗
PubMed1998

Maternal-fetal transmission of human papillomavirus.

OBJECTIVE: To investigate the maternal-fetal transmission of human papillomavirus (HPV). METHODS: Samples of exfoliated cervical cells were obtained from 73 pregnant women on their third-trimester examinations. Samples of fetal membranes, amniotic fluid and nasopharyngeal swab were obtained from the parturients and their neonates. The presence of HPV types 16, 18 and 35 deoxyribonucleic acid was detected by polymerase chain reaction (PCR) and endonuclease method. RESULTS: HPV types 16, 18 and 35 deoxyribonucleic acid were found in 26 (35.6%) of 73 specimens of cervical cells obtained from the parturients, and in 31 (42.5%) of 73 specimens of fetal membranes, 6 (15.4%) of 39 specimens of amniotic fluid, and 5 (14.7%) of 34 neonatal nasopharyngeal swabs obtained from the neonates. The restriction endonuclease analysis of the amplified products showed that HPV types 16, 18 and 35 were positive in 24.7%, 9.6% and 1.4% respectively of parturients, and 11.0%, 4.1% and 0 respectively of neonates. The maternal-fetal transmission rate of HPV was 50% (7/14) for spontaneous vaginal delivery, and 33.3% (4/12) for cesarean section. CONCLUSION: HPV can be transmitted from mothers to their babies not only through the placenta during pregnancy, but also through the genital tract during delivery.

Female↗
PubMed1998

[Changes of T-SOD activity and MDA, GSH contents in blood of guinea pigs after exposure to narrow-band noise].

In order to evaluate the changes of lipid peroxide response induced by free radical after intense noise exposure, levels of T-SOD and MDA in serum and GSH in blood of guinea pigs were determined. Sixty male adult guinea pigs were used. The narrow band noise was centered at 1000Hz with 100Hz band width 126 dB SPL. It was found: 1) SOD activity in serum increased after 5d exposure (P > 0.05), but decreased after 10d exposure (P > 0. 05); 2) contents of MDA in serum increased (P < 0.05) and contents of GSH in blood decreased with increase of exposure time (P < 0.01). It shows that the lipid peroxide response induced by free radicals increased after intense noise exposure and it is possible to use free radical scavengers and/or antioxidant in prevention and treatment of noise induced damage.

Animals↗
PubMed1998

[Distribution of substance P receptors in rat nasal mucosa of allergic rhinitis].

OBJECTIVE: To explore the potential role of substance P receptor (SPR) in the initiation and development of allergic rhinitis (AR). METHODS: Twenty healthy rats were randomly divided into two groups. A model of allergic rhinitis in rat was established by using ovalbumin intraperitoneal immunization and nasal antigen challenge. The nasal mucosa obtained from seven out of ten AR models as well as ten normal controls were studied routinely by HE and immunohistochemical staining to observe the distribution and changes of SPR. RESULTS: The study showed that immunoreactivity to SPR was present both on the surface and in the cytoplasm of epithelial cells, eosinophils, glandular cells and its ducts, mast cells, plasmocyte and other monocytes. During nasal hypersensitiveness, the staining density and the positive staining cells increased significantly as compared with those in normal controls. CONCLUSION: The increase of SPR in nasal mucosa in rat AR model indicates that SPR might play a critical role in the development of AR.

Animals↗
PubMed1998

[Local amyloidosis of stomach].

OBJECTIVE: To improve the diagnostic rate of local amyloidosis of stomach. METHOD: One case of local amyloidosis of stomach was reported and the literatures were reviewed on the etiopathology, clinical features, diagnosis, treatment and prognosis. RESULT: The patient was negative for family history and other chronic disease. Total gastrectomy was taken and was eventually found to have localized amyloidosis of stomach and regional lymph nodes. The amyloidosis was found to be of AA amyloidosis. Multiple biopsy specimens taken from esophagus, duodenum, rectum and bone marrow showed no amyloid deposition. CONCLUSION: Amyloidosis should be considered in the differential diagnosis of gastric tumors, and also should be removed by operation if complications are to be prevented.

Amyloidosis↗
PubMed1998

[Functional changes of forelegs of rats after C6 and C8 nerve roots resection: experimental study].

OBJECTIVE: To find new nerve roots as dynamic source, we observed the effect of C(6) and C(8) resection on the function of forelegs of roots. METHOD: Considering the relationship between C(6) and biceps brachii muscle, C(8) and flexor digitorum profundus muscle, we resected C(6) and C(8) nerve roots of right side as the experimental side and compared with the left side. The position, pace, appearance of ulcer were observed on the foot and the phenomena of self-injury were seen regularly. The EMG and tensile strength of biceps brachii and flexor digitorum profundus muscles were measured immediately at two weeks and four weeks after operation. RESULT: The position of two sides of the rats was symmetrical. There were no limp, ulceration and phenomena of self-injury. Normal wave figure in EMG was noted in the experimental side. There was no significant difference in t test in EMG wave amplitude, maximum tetanized systole tensile strength and duration of isometric contraction. CONCLUSION: C(6) and C(8) nerve roots resection has no obvious influence on function of the leg.

Animals↗
PubMed1998

[Determination of adenosine in Rehmannia glutinosa Libosch. by HPLC].

OBJECTIVE: To establish a method to determine the contents of asenosine in different species of Rehmannia glutinosa. METHOD: The contents were determined by HPLC, with a column of KYWG-C18 as stationary phase, 6% ace tonitrile as mobile phase and detecting wavelength at 260 nm. RESULT: Adenosine has a good linearity in the range of 0.002 mg/ml-0.01 mg/ml, Y = 1.7742 x 10(-4) + 8.9021 x 10(-7) X, r = 0.9995. The average recovery is 94.1% and RSD = 1.86% (n = 5). CONCLUSION: The method is fast, reliable and simple.

Adenosine↗
PubMed1998

[Purification of hepatitis B virus antigen and its application in detection of human serum antibody].

A recombinant plasmid DNA pBV220/eAg provided by professor Zhou Jian was transferred into DH5 alpha celes. The effectively expressed strain was harvested after cloning. It was then incubated in 30 degrees C for 3 hrs and 42 degrees C for 6 hrs, the HBeAg protein was induced. After purification of the protein by DEAE-Sepharose Fast Flow chromatography, the purified protein was analyzed by SDS-PAGE electrophoresis and Coomassic brilliant blue R250 stain and only one single protein band was seen, Its specificity was demonstrated by Western-blot and Immunodot. 49 HBeAb positive sera of hepatitis B patients could be specifically detected with the purified HBeAg by ELISA and immunostrip assay, but the latter was more sensitive and specific.

Antibodies, Viral↗
PubMed1998

[Measurement of interfragmentary micromovement induced by mechanical vibration with accelerometers in vitro].

The interfragmentary micromovement induced by mechanical vibration was measured in vitro in seven preserved adult cadaveric femurs by using accelerometers. Accuracy analysis of this method indicated that it can detect relative interfragmentary micromovement as small as 0.1 mm or below under certain range of frequency. Also, the results have shown that the mechanical vibration can induce interfragmentary micromovement under intramedullary nailing, but it can not do so under plate fixation.

Adult↗
PubMed1998

[The vibration-rotational analysis of the high resolution ir spectrum of the CH3D molecule].

High-resolution Fourier transform spectra of the band of the CH3D molecule near 6428cm(-1) have been recorded on a BRUKER IFS 120HR Fourier-transform spectrometer with multipass cell with a length of 20m, an unapodized resolution of 0.004cm(-1) was achieved. Vibration-rotation analysis in Local-mode can provide accurate enough initial values to predict the band origins. The vibration-rotation transitions of CH3D molecule were assigned by using the ground state combination differences and least-squares fitted to yield ten vibration-rotation constants for the band of CH3D molecule near 6428cm(-1). Vibration assignment in Normal-mode and Local-mode expressed that the band of CH3D molecule near 6428cm(-1) is 3V2 vibration states of CH3D molecule.

English Abstract↗