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Biomedical subjects

R Wu

Publications and source records attributed to R Wu.

At least 145 records · Page 8Linked to original sources
PubMed1999

[Effect of cigarette smoke extract on E-cadherin expression of airway epithelial cells].

OBJECTIVE: To explore the possible mechanism of injury by smoking, and the effect of cigarette smoke extract (CSE) on E-cadherin (ECD) expression in airway epithelial cells (AEC) was observed. METHODS: Mouse trachea and pig AEC were cultured in vitro. After CSE exposure, the expression of ECD in AECs was evaluated using immunohistochemical stain and image analysis. RESULTS: ECD was distributed on the plasma membrane at the cell junctions of AECs. At 12th and 24th hour after CSE exposure, the ECD expression on membrane decreased, whereas the cytoplasmic expression increased (P < 0.01) as compared with the normal controls. The expression at 24th hour was higher than that at 12th hour (P < 0.01). CONCLUSIONS: CSE decreases the membranous expression of ECD in AECs, but increases the cytoplasmic expression. The change of ECD expression may mediate the airway epithelial injuries by smoking.

Animals↗
PubMed1999

[The study of E-cadherin expression on injury and repair of epithelium of respiratory tract in smoking mice].

OBJECTIVE: To investigate effects of smoking on E-cadherin (E-cd) expression of injury and repair of respiratory tract epithelium by observation of dynamic expression of E-cd on epithelial cells of respiratory tract in smoking mice. METHODS: Immunohistochemistry SP technique was used to examine E-cd expression on epithelial cells of respiratory tract in smoking mice of different stages and dosages and the morphological changes observed by light and electron microscopy respectively. RESULTS: Four and twelve weeks after smoking, the E-cd expression in the epithelial cells was significantly down-regulated compared with the control group (P < 0.01). Morphologically, the intercellular junction was loose, and the epithelial cells were injured and proliferated on the same time. Eight weeks after smoking, however, the E-cd expression was not different from that of the control group (P > 0.05). CONCLUSIONS: Smoking is able to cause wavy change of the E-cd expression on the epithelial cells which may play an important role in the injury and repair of the epithelial cell of the respiratory tract.

Animals↗
PubMed1999

[Protective effect of mutant dihydrofolate reductase gene on human peripheral blood CD34+ cells against methotrexate].

OBJECTIVE: To examine if human peripheral blood hematopoietic progenitor cells transduced with mutant dihydrofolate reductase(mDHFR) gene may increase their resistance to metrotrexate(MTX). METHODS: After enrichment with a high-gradient magnetic cell sorting system(MACS), the peripheral blood CD34+ cells were transfected with supernatant of retrovirus containing human mDHFR cDNA. Colony formation of hematopoietic progenitor cells was utilized to evaluate mDHFR-conferred resistance to MTX. The number of colonies formed from every 500 cells seeded was counted and expressed as the percentage of colony formation. RESULTS: After the mD-HFR-transduced CD34+ cells had been screened in vitro in medium containing 20 nmol.L-1 MTX for 14 days, the percentage of colony formation of mDHFR cDNA-transduced and of mock-transduced CD34+ cells was 29.4% and 16.3%, respectively (P < 0.01). The resistance to MTX was increased twofold. CONCLUSION: Transduction of mDHFR gene could confer the resistance of human hematopoietic progenitor cells to MTX toxicity.

Antigens, CD34↗
PubMed1999

[Lutembacher's syndrome].

OBJECTIVE: To compare classical and acquired Lutembacher's syndrome (mitral restenosis after percutaneous balloon mitral valvuloplasty) in attempt to know their different in pathophysiology, diagnosis, and surgical treatment. METHODS: The data from 22 cases of classical and acquired Lutembacher's syndrome who underwent surgical treatment in the same period were analyzed. RESULTS: No death occurred in the classical group. In the acquired group the mortality however was 42.8% for those highly complicated with pulmonary hypertension and right heart failure. CONCLUSIONS: Classical Lutembacher's syndrome can be corrected satisfactorily. The acquired one deteriorates rapidly with severe pulmonary hypertension and right heart failure, and needs early surgical intervention reduce the operation mortality.

Adult↗
PubMed1999

[Phacoemulsification with foldable intraocular lens implantation through a limbus tunnel incision].

OBJECTIVE: To advance and evaluate the technique and therapeutic effects of phacoemulsification with foldable intraocular lens implantation through a limbus tunnel incision. METHODS: The surgery was performed through a 3.2 limbus tunnel incision on 110 eyes of 103 patients with senile, complicated, congenital and traumatic cataracts. RESULTS: Postoperatively, the visual acuities with spherical correction or without correction were 0.5 or better in 90.0% of the eyes at one day, and 1.0 or better in 42.5%, 63.7% and 68.0% at one week, one month and three months respectively. The mean postoperative astigmatism was (1.00 +/- 0.68) D at one week and only 0.07D more than the mean preoperative one (P > 0.05). There was also no statistical difference between the mean preoperative astigmatism and postoperative astigmatism at one and three months, which were respectively (0.91 +/- 0.55) D and (0.83 +/- 0.57) D. The mean postoperative astigmatism was almost the same as compared between the scleral tunnel incision and clear corneal incision groups. CONCLUSION: The phacoemulsification with foldable intraocular lens implantation through a limbus tunnel incision can reduce postoperative astigmatism and shorten the period of visual rehabilitation as the operation through a scleral tunnel or a clear corneal incision, and in the mean time the former method can overcome the shortages of the latter two methods.

Adolescent↗
PubMed1999

[Secondary glaucoma after anterior chamber intraocular lens implantation].

OBJECTIVE: To investigate the intraocular pressure level, the change of anterior chamber angle and the occurrence of secondary glaucoma after anterior chamber intraocular lens (AC-IOL) implantation. METHODS: Sixty-two AC-IOL implanted eyes were followed up postoperatively for 3 months to 7 years (mean 31 months). The examination of anterior chamber angle was emphasized. The type of cataract mainly included senile and traumatic. The operation performed were lensectomy with anterior vitrectomy or extracapsular cataract extraction (ECCE) combined with primary or secondary AC-IOL implantation. RESULTS: The incidence of postoperative peripheral anterior synechia (PAS) of iris was 87.1% and that of the secondary glaucoma (mainly the angle-closure) was 11.3%. The incidence of the glaucoma after ECCE with primary or secondary implantation was 17.4%, while that after ECCE combined with anterior vitrectomy was 0%. CONCLUSION: The main causes of the secondary glaucoma are possibly the rupture of posterior capsule and vitreous loss during the surgery leading to postoperative severe uveitis and pupillary block. To prevent its occurrence, it is important to combine ECCE with anterior vitrectomy.

Adolescent↗
PubMed1999

[In vitro adherence of bacteria to intraocular lenses of different materials].

OBJECTIVE: To compare the in vitro adherence of different bacteria onto the surface of various intraocular lenses (IOLs). METHOD: Electron microscopic and bacterial culture quantitative methods were used to study the adherence of Staphylococcus (S) epidermidis, Staphylococcus aureus and Pseudomonas (P) aeruginosa onto the surface of PMMA and other three foldable IOL materials (HEMA, ACRY, SI). RESULTS: S. Epidermidis: HEMA < ACRY < SI < PMMA; S. aureus: HEMA was the least and PMMA was the most, no significant difference between ACRY and SI IOLs; P. aeruginosa: HEMA was the least while no significant difference among PMMA, SI and ACRY IOLs (P > 0.05). CONCLUSION: The foldable IOLs have the potent ability to reduce the infectious endophthalmitis after surgery of extraction of cataract with IOL implantation.

Acrylic Resins↗
PubMed1999

[Effect of bFGF, IGF-I and their synergy on the mitogenesis of bovine lens epithelial cells].

OBJECTIVE: To assess the effect of basic fibroblast growth factor (bFGF), insulin like growth factor-I (IGF-I) and their synergy on the mitosis of bovine lens epithelial cells (BLECs). METHODS: BLECs were cultured in vitro. The fourth passage cells were inoculated into 24 well tissue culture plates, treated with different concentrations of bFGF, IGF-I, and bFGF + 20 microg/L IGF-I for 20 hours, (3)H-thymidine was added for 16 hours, then the radioactivity was determined by liquid scintillation counting. RESULTS: Either bFGF (1 - 100 microg/L) or IGF-I (20 - 100 microg/L) increases mitosis of BLEC significantly, and 20 microg/L IGF-I may increase bFGF induced mitogenesis. CONCLUSION: Growth factor and their synergic effect may play an important role in lens epithelial cell proliferation.

Animals↗
PubMed1999

[Effects of high fluoride intake on the fluoride of femora, teeth and some biochemical indexes in rats].

In order to approach practicable indexes for assessing the effects of the products which are intended to be used to prevent endemic fluorosis, Wistar rats were fed with fluoridated water(50 mg/L) for four weeks. After only one week treated with fluoride, a higher activity of NAG(N-acetyl-beta-D-glucosaminidase) in urine, ChE(cholinesterase) in blood and increased urinary excretion of fluoride (compared with the control, P < 0.01) were observed, and these changes were lasted to the end of the fourth week of the study, but hydroxyproline in serum and urine had not been changed in both groups. After four weeks, the fluoride levels in the femora and teeth of fluoride treated group were ten times higher than that of the control group. According to the results, fluoride in bones and teeth must be taken as key indexes, the activities of NAG in urine and ChE in blood should be taken into consideration for assessing the effects of fluoride protagonist.

Acetylglucosaminidase↗
PubMed1999

[Cardic death and apoptosis of myocardium].

TdT-mediated Dutp nick end labeling (TUNEL) method was applied to detect apoptosis of myocardium of corpses dying from cardiac death. For arteriosclerotic coronary heart death, diffused apoptosis was observed around the border zones of histologically infarcted myocardium, and in the epithelial and smooth muscle of arteries. Few apoptosis cells were present for hypertensive heart death, and none for corpses dying from falling and hanging. Myocardium apoptosis may provide a new target for heart failure.

Apoptosis↗
PubMed1998

Structure and organization of the genes encoding mouse small proline-rich proteins, mSPRR1A and 1B.

Two genomic clones comprising the entire coding sequence of mouse SPRR1A and 1B genes were isolated and sequenced. Sequence analysis of the 1A and 1B genomic clones indicated that both genes contain two exons separated by an intron slightly larger than 1.1kb in size (1147 and 1152nt, respectively). This type of genomic structure is identical to the counterpart of human SPRR1 gene and other genes encoding for cornified envelope proteins. Primer extension analysis using 1A and 1B gene-specific primers indicates that 1A gene is expressed in squamous tissues such as skin and esophagus, whereas 1B gene is expressed in papilloma tumors but not in squamous tissues. The first 300nt of 5'-flanking region of the mouse SPRR 1A and 1B genes reveal an overall approximately 50% identity to the human counterpart. However, there is a high degree of identity (?75%) at the promoter region containing a TATA box and TRE/TRE-like motifs. Both TATA and TRE/TRE-like motifs are almost identical in sequence and positions to those found in the counterpart of human promoter. Using transient transfection for the analysis of promoter activity, we observed that both 1A and 1B 5'-flanking regions contain the promoter activity to direct the expression of the reporter gene, chloramphenicol acetyltransferase, in airway epithelial cells in a fashion similar to that observed in the human counterpart. These results indicate a conserved nature of genetic structure and regulation of SPRR1 gene expression between human and mouse.

Amino Acid Sequence↗
PubMed1998

Low-Rate Dynamic Contact Angles on Poly(methyl methacrylate) and the Determination of Solid Surface Tensions.

Low-rate dynamic contact angles of nine liquids on a poly(methyl methacrylate) (PMMA) polymer are measured by an automated axisymmetric drop shape analysis-profile (ADSA-P). It is found that two liquids dissolved the polymer on contact. From the experimental contact angles of the other seven polar and nonpolar liquids, it is found that the liquid-vapor surface tension times cosine of the contact angle changes smoothly with the liquid-vapor surface tension (i.e., gammalnucos theta depends only on gammalnu for a given solid surface). The dependence of gammalnucos theta on gammasnu is explicitly illustrated by replacing the solid surface from the PMMA to other methacrylate polymers: such a procedure shifts the curves in a very regular manner. Thus, because of Young's equation, gammasl depends only on gammalnu and gammasnu. This contact angle pattern is in harmony with those from other inert and noninert (polar and nonpolar) surfaces. The solid-vapor surface tension of PMMA calculated from the equation of state approach for solid-liquid interfacial tensions is found to be 38.5 mJ/m2, with a 95% confidence limit of +/-0.5 mJ/m2 from the experimental contact angles of the seven liquids. Copyright 1998 Academic Press.

Journal Article↗
PubMed1998

Antibodies to endothelial cells in borderline hypertension.

BACKGROUND: Antibodies to endothelial cells (aECs) and to cardiolipin (aCLs) are implicated in autoimmune diseases like systemic lupus erythematosus vasculitis. Beta2-Glycoprotein 1 (beta2GP1) is a cofactor for aCLs. The present study investigated the possible role of aECs, aCLs, and abeta2GP1 in borderline hypertension. METHODS AND RESULTS: Seventy-three men with borderline hypertension (BHT) and 73 age-matched normotensive (NT) men (diastolic blood pressure, 85 to 94 and <80 mm Hg, respectively) were recruited from a population screening program. Antibody levels were determined by ELISA. Presence of carotid atherosclerosis was determined by B-mode ultrasonography, and 29 individuals had atherosclerotic plaques. BHT men had significantly higher aEC and abeta2GP1 levels of IgG class than NT control subjects (P=0.029 and P=0.0001, respectively). aEC levels of IgM class were higher in BHT (P=0.012), but not abeta2GP1 levels. There was no correlation between aCL levels and BHT. Individuals with atherosclerotic plaques had significantly higher aEC levels of both IgG (P=0.042) and IgM subclasses (P=0.018) than those without plaques, but no difference was found in aCL and abeta2GP1 levels. Endothelin and aECs of IgM class were significantly associated. CONCLUSIONS: We demonstrate the first evidence of a significant elevation of aEC and abeta2GP1 levels in borderline hypertension. These findings provide a new link between hypertension and atherosclerosis and indicate that humoral immune reactions to the endothelium may play an important role in both conditions.

Adult↗
PubMed1998

IEX-1L, an apoptosis inhibitor involved in NF-kappaB-mediated cell survival.

Transcription factors of the nuclear factor-kappaB/rel (NF-kappaB) family may be important in cell survival by regulating unidentified, anti-apoptotic genes. One such gene that protects cells from apoptosis induced by Fas or tumor necrosis factor type alpha (TNF), IEX-1L, is described here. Its transcription induced by TNF was decreased in cells with defective NF-kappaB activation, rendering them sensitive to TNF-induced apoptosis, which was abolished by transfection with IEX-1L. In support, overexpression of antisense IEX-1L partially blocked TNF-induced expression of IEX-1L and sensitized normal cells to killing. This study demonstrates a key role of IEX-1L in cellular resistance to TNF-induced apoptosis.

Animals↗
PubMed1998

Profiling expression patterns and isolating differentially expressed genes by cDNA microarray system with colorimetry detection.

A high-density cDNA microarray with colorimetry detection system to simultaneously monitor the expression of many genes on nylon membrane is described and characterized. To quantify the expression of genes and to isolate differentially expressed genes, the southern hybridization process on filter membranes was employed. The levels of gene expression were represented by color intensities generated by colorimetric reactions in place of hazardous radioisotopes or costly laser-induced fluorescence detection. The gene expression patterns on nylon membranes were digitized by devices such as an economical flatbed scanner or a digital camera. The quantitative information of gene expression was retrieved by image analysis software. Quantitative comparison of the northern dot-blotting method with the microarray system is described. Applications employing single-color detection as well as dual-color detection to isolate differentially expressed genes among thousands of genes are demonstrated.

Blotting, Northern↗
PubMed1998

Photochemically induced focal cochlear lesions in the guinea pig: I. DAB staining and SEM study.

A photochemical reaction was used to produce focal microcirculation disorders in the guinea pig cochlea. Temporal bones were removed at various intervals between 5 minutes and 1 month after infusion of rose bengal (RB) and illumination. Infused but unilluminated contralateral cochleae served as controls. Dissected cochlear structures were stained by 3,3'-diaminobenzidine (DAB) peroxidase substrate medium. After observation by light microscopy (LM), the same specimens were processed and observed by scanning electron microscopy (SEM). Dilation of strial capillaries and destruction of strial epithelial cells became apparent at 1 hour after illumination. Tightly packed red blood cells were found filling the severed end of markedly dilated strial capillaries at 24 hours after the procedure. DAB staining of the osseous spiral lamina indicated vascular change with vessel dilation in the illuminated area. At 1 week after illumination, the lesion area of the stria vascularis and spiral prominence was replaced by a layer of larger, flat cells. At 1 month after illumination, all vascular supply to the cochlear lateral wall disappeared at the site of illumination. All lesions remained focal and showed no sign of expansion or reduction throughout the observation period. The cochlear duct of the guinea pig appears to be segmentally nourished by the capillary system. Observation of DAB stained tissue by LM and SEM proved to be informative in the study of microcirculation disorders of the inner ear.

3,3'-Diaminobenzidine↗