Biomedical subjects

M Wu

Publications and source records attributed to M Wu.

At least 163 records · Page 9Linked to original sources

PubMed2000

Vitronectin protects alveolar macrophages from silica toxicity.

Silicosis is an interstitial lung disease caused by the inhalation of crystalline silicon dioxide. Current concepts suggest that a crucial step in the development of silicosis is silica-induced injury of alveolar macrophages (AM). The adhesive protein vitronectin is a natural constituent of the lung, in which its function is largely unexplored. This study investigated a possible role for vitronectin in protecting AM from silica exposure. In this study, the concentration of vitronectin was shown to be increased in the bronchoalveolar lavage fluid of silica-treated rats. Vitronectin affinity for silica was shown both in vitro and in vivo by immunostaining. Vitronectin reduced silica-induced injury to cultured AM as determined with the (51)Cr release assay. Vitronectin reduced silica-induced free radical production as determined with a cell-free thiobarbituric acid assay. Additionally, vitronectin reduced the silica-induced respiratory burst in AM as determined with chemiluminescence. This study suggests that vitronectin may protect AM during the initial exposure to silica.

Animals↗

PubMed2000

Skeletal benefits of alendronate: 7-year treatment of postmenopausal osteoporotic women. Phase III Osteoporosis Treatment Study Group.

We report here the second 2-yr extension of a clinical trial among postmenopausal women; 235 women continued blinded treatment with 5 or 10 mg alendronate daily, and 115 women who had been treated with alendronate for 5 yr were switched to blinded placebo. Continuous treatment with alendronate (10 mg daily) for 7 yr increased lumbar spine bone mineral density (BMD) by 11.4% compared to baseline. After the initial 18 months, each additional year of treatment through yr 7 increased spine BMD by 0.8% for the 10-mg dose and 0.6% for the 5-mg dose, with significant increases during yr 6-7. Previously reported increases in BMD at other skeletal sites and decreases in biochemical markers of bone turnover remained stable during yr 6-7. Among women previously taking alendronate for 5 yr who were switched to placebo, there was no significant decline in BMD at the spine or hip, whereas small, but significant, decreases in BMD at the forearm and total body and small increases in biochemical markers were observed. The safety and tolerability profiles were similar to those of placebo. This is the largest published long-term study of antiresorptive therapy. Our findings indicate that long-term alendronate treatment is well tolerated and effective for 7 yr. Increases in spinal BMD continue for at least 7 yr, and other skeletal benefits are maintained. Discontinuation does not lead to accelerated bone loss, but continuous treatment yields better skeletal benefits than shorter treatment.

Absorptiometry, Photon↗

PubMed2000

Immunohistochemical demonstration of inducible nitric oxide and nuclear factor-kappa B with reference to age-related changes in the mouse spiral and vestibular ganglion.

The morphology and immunohistochemistry of inducible nitric oxide synthase (iNOS) and nuclear factor-kappa B (NF-kappa B) were studied on the spiral and vestibular ganglion of young and old ddy mice. The significant decrease in the number of the spiral ganglion cells and a significant expression of iNOS and NF-kappa B were observed in old mice. In contrast, in the vestibular ganglion of all animals examined, decrease in the number of the ganglion cells or expression of iNOS and NF-kappa B were not observed. Although the relevance of enzymatic systems for the protection of vestibular ganglion cells in old individuals from harmful oxidative stress increased with aging should be further clarified, lack of harmful stress due to nitric oxide (NO) may be one of the plausible reasons for that the vestibular ganglion cells were not decreased in number with aging, since iNOS was not detected in the vestibular ganglion cells in the animals tested in the present study.

Aging↗

PubMed2000

The effects of recombinant RA538 and antisense c-myc adenovirus on tumor cells and the molecular mechanism concerned.

OBJECTIVE: Compare the biological effects of recombinant RA538 and antisense c-myc adenovirus on human gastric cancer cell line (SGC7901) and explore the molecular mechanism in vitro and in vivo. METHODS: SGC7901 cells were treated with Ad-RA538, Ad-AS c-myc or Ad-LacZ. MTT, DNA ladder, TUNEL and FCM, RT-PCR, Western blot analysis, the tumorigenicity in nude mice and experimental therapy of the nude mice were used. RESULTS: Ad-RA538 and Ad-ASc-myc could strongly inhibit cell growth and induce apoptosis of SGC7901 cells. The growth of the Ad-RA538- and Ad-ASc-myc-infected SGC7901 cells were inhibited by 76.3% and 44.1% respectively. The over expression of RA538 and ASc-myc could down-regulate expression of c-myc, bcl-2 and cyclinD1 gene and up-regulate expression of bax gene, but it could not regulate expression of p53, p16, TGase, and ras gene. The tumorigenicity of Ad-RA538 or Ad-ASc-myc in nude mice showed that three of three mice failed to form tumor, compared with Ad-LacZ and parent SGC7901 cells from 7 to 30 days. Experimental therapy of the nude mice bearing subcutaneous tumor of SGC7901 cells showed that intratumor instillation of Ad-RA538 and Ad-ASc-myc inhibited the growth of the tumors. Ad-RA538- and Ad-ASc-myc-treated tumors were inhibited by 60.7% or 68.9% respectively, compared with the tumor injected with Ad-LacZ and mock. CONCLUSION: The expression of Ad-RA538 and Ad-ASc-myc can inhibit growth and induce apoptosis of gastric cancer cell in vitro and in vivo. RA538 and ASc-myc relate to c-myc, bcl-2, cyclinD1 and bax gene closely and have noticeable biologic effects on gastric cancer cells.

Adenoviridae↗

PubMed2000

Studies of MAL gene in human esophageal cancer by RNA in situ hybridization.

OBJECTIVE: To observe the expression of MAL gene mRNA in esophageal cancer tissue and adjacent epithelial mucosa. METHODS: Non-radioactive RNA in situ hybridization. RESULTS: MAL gene was expressed in all epithelia of 33 matched samples but only in 8 of esophageal cancer tissues. Differential expression between esophageal cancer tissues and adjacent epithelia was not related to clinical parameters. CONCLUSION: Down-regulation of MAL may be an important event in the development of esophageal cancer.

Down-Regulation↗

PubMed2000

Intermediate and late rheumatoid arthritis treated by tonifying the kidney, resolving phlegm and removing blood stasis.

Eighty-seven cases of intermediate and late rheumatoid arthritis were treated with Instant Shu Guan Wen Jing Granules ([symbol: see text] Relaxing Joints by Warming Channels) and Instant Shu Guan Qing Luo Granules ([symbol: see text] Relaxing Joints by Removing Heat from the Lung Channel) to tonify the kidney, resolve phlegm and remove blood stasis, and compared with 41 cases treated with Instant Wang Bi Granules ([symbol: see text] Prescription for Arthralgia-syndrome). The treatment produced a clinical cure rate of 54.0% and a total effective rate of 90.8% as in against 29.3% and 73.2% respectively in the control group. The difference was significant (P < 0.01). Improvement in main symptoms and laboratory findings in the treatment group was all more marked than that in the control group (P < 0.05 or P < 0.01), with no side effects observed.

Adult↗

PubMed2000

[The construction of PQE-ARL-1 recombinant expression plasmid and the preparation and purification of ARL-1 protein].

OBJECTIVE: To further understand the function and biological activity of aldose reductase like-1 (ARL-1), and to provide the basis for the preparation of the specific antibody against ARL-1. METHODS: The ARL-1 cDNA was cloned into procaryotic expression vector PQE-30 and the recombinant ARL-1 expressed in E.coli M(15); then Ni(+)-NTA agarose columns were used to purify the ARL-1 protein. RESULTS: With the digestion of the enzymes, we identified that the ARL-1 gene was inserted into the procaryotic expression vector PQE-30. The expression products of PQE-ARL-1 (human recombinant ARL-1) showed a single protein band on SDS-PAGE. The molecular weight of ARL-1 was approximately 37.7 x 10(3) and the expression level was about 25% of the total bacterial protein. The concentration of ARL-1 protein was about 100mg/L. CONCLUSION: The construction of the recombinant plasmid PQE-ARL-1 and the preparation of the protein ARL-1 have laid a solid foundation for further studying the function of ARL-1 and preparing the specific antibody against ARL-1.

Aldehyde Reductase↗

PubMed2000

Lipid-altering efficacy and safety of simvastatin 80 mg/day: worldwide long-term experience in patients with hypercholesterolemia.

BACKGROUND AND AIM: Clinical data suggesting that larger decreases in low density lipoprotein cholesterol (LDL-C) result in greater reductions in coronary heart disease events have led to the establishment of aggressive LDL-C targets for the treatment of hypercholesterolemia. In view of this, the efficacy and safety of a new maximum dose of simvastatin, 80 mg, were evaluated in 9 studies involving 2819 hypercholesterolemic patients. This report focuses on the combined results from the 4 main or Pivotal studies in which a total of 1936 patients received simvastatin 40 or 80 mg for 36 to 48 weeks. METHODS AND RESULTS: The Pivotal studies had similar randomized, multicenter, controlled, double-blind, parallel-group designs. Their combined results demonstrated a significant advantage in the LDL-C-lowering effect for the 80 mg dose. At week 24, the mean percentage reductions (95% confidence intervals) from baseline in LDL-C for the 40 and 80 mg groups were -39.8% (-40.9, -38.7) and -45.7% (-46.5, -45.0) respectively (p < 0.001, between groups), and larger reductions in total cholesterol and triglycerides were also observed in the 80 mg group. Both doses were well tolerated. No new or unexpected adverse events were observed and the overall clinical event profiles were similar in the two groups. Clinically significant hepatic transaminase increases (> 3 times the upper limit of normal/ULN) and myopathy (muscle symptoms plus creatine kinase increase > 10 times ULN) occurred infrequently with both doses. Simvastatin 80 mg had a comparable efficacy and safety profile in women and men as well as in non-elderly and elderly patients. CONCLUSIONS: Simvastatin 80 mg provides additional LDL-C and triglyceride reductions compared to the 40 mg dose and has an excellent safety and tolerability profile.

Adolescent↗

PubMed2000

Overexpression of Bcl-2 partly inhibits apoptosis of human cervical cancer SiHa cells induced by arsenic trioxide.

OBJECTIVE: To study the biological effect of arsenic trioxide (As2O3) on human cervical cancer SiHa cells and SiHa cells overexpressing bcl-2 gene. METHODS: SiHa cells with overexpression of Bcl-2 (SiHa-Bcl2 cells) were established by transfecting SiHa cells with Bcl-2 expression vector. The sensitivities of SiHa and SiHa-Bcl2 cells to As2O3 were determined using MTT (Thiazolyl blue) reduction and colony forming ability assay, morphological analysis, flow cytometric analysis, DNA agarose gel electrophoresis, in situ cell death detection (TUNEL), Northern blot, RT-PCR and Western blot. RESULTS: As2O3 inhibited the growth of SiHa cells and induced G2/M arrest and apoptosis of the cells. RT-PCR and Western blot analysis revealed that As2O3 induced SiHa cell apoptosis possibly via inhibiting the expression of HPV16 E7 and decreasing the expression of c-myc. However, we found that SiHa-Bcl2 cells partly resisted As2O3 induced apoptosis, which might be related to the prevention of the down-regulation of HPV16 E7 and c-myc gene expression. Nevertheless, As2O3 at a high concentration could still induce apoptosis of SiHa-Bcl2 cells mainly via decreasing Bcl-2 expression and slightly inhibiting viral gene expression. CONCLUSION: As2O3 is an inducer of the apoptosis of human cervical carcinoma cells and the cells overexpressing Bcl-2 can partly resist As2O3 induced apoptosis, but the exact mechanism is unclear.

Antineoplastic Agents↗

PubMed2000

[Treatment and prognostic factors for stage IV epithelial ovarian cancer].

OBJECTIVE: The aim of the study was to evaluate the influence of surgical debulking and chemotherapy on survival in patients with stage IV epithelial ovarian cancer. METHODS: Medical records and follow-up sheets were retrospectively reviewed for all women with International Federation of Gynecology and Obstetrics stage IV epithelial ovarian cancer treated between January, 1982 and December, 1997 in our hospital. Survival analysis and comparison were performed using Kaplan-Meier method and t-test. The COX proportional hazards regression model was used to identify independent variables associated with survival improvement. RESULTS: Twenty-five women with stage IV epithelial ovarian cancer were available. Median age was 51 years (range 33-72 years). Papillary serous histology was found in 12/75 patients (48%). Thirteen patients (52%) had grade 3 tumors. Metastases by the International Federation of Gynecology and Obstetrics (FIGO) criteria were found in 7 cases in supraclavicular lymph node (28%), 6 cases in liver (24%) and 4 cases with malignant pleural effusion. All patients received surgical debulking with 9 cases (36%) having in optimal cytoreduction. Overall median survival of 15.0 months was achieved, while optimal debulked patients' median survival was 28.4 months compared to 14.7 months for the patients with bulky residual disease (P < 0.01). Median survival for the patients with 6 or more courses of chemotherapy postoperatively was 28.5 months, compared to 6.5 months for the patients with less than 6 courses (P < 0.01). Optimal debulking surgery and courses of chemotherapy retained significance as indepent predictors of survival based on multivariate analysis. CONCLUSION: Optimal surgical debulking and active postoperative chemotherapy appear to improve the prognosis of the patients with stage IV epithelial ovarian cancer under the premise of keeping quality of life.

Adult↗

PubMed2000

[Mutation and expression of nm23-H1 and CD44 gene in prostate cancers].

OBJECTIVE: To study the role of nm23-H1 and CD44 gene in carcinogenesis and metastasis of prostate cancers. METHODS: Expression of nm23-H1/NDPK and CD44 protein were analyzed in 32 cases of prostate cancers (Pca) and 12 control of benign prostate hyperplasia (BPH) paraffin embedded tissue by immunohistochemistry. Mutation and expression of their genes were detected by silver SSCP method, semiquantitative RT-PCR, and southern blot hybridization analysis respectively in 25 cases of fresh Pca and 15 control BPH tissue. RESULTS: nm23-H1 gene point mutation was detected in 13.3% (2/15) of Pca. Compared with the control tissue, the expression of nm23-H1 gene was increased significantly on both mRNA and protein levels in the carcinoma tissue (P < 0.05). The expression of nm23-H1 protein was also increased significantly in Pca with metastasis. The expression of CD44 standard form (CD44s) protein was significantly reduced in most Pca compared with BPH tissue. CD44s mRNA was detected in all Pca and BPH tissue, whereas CD44 variant (CD44v) without CD44v6 was mainly detected in carcinoma tissue. CONCLUSIONS: The altered expression of CD44s and CD44v may co-regulate in the carcinogenesis and progression, whereas nm23-H1 gene may play a different role from CD44 in the progression of prostate cancer. CD44v6 may be a useful but not significant tool for detection of colon or bladder cancers.

Gene Expression↗

PubMed2000

[E-selectin and its ligand-sLeX in the metastasis of hepatocellular carcinoma].

OBJECTIVE: To study the significance of E-selectin and its ligand-sLeX in the metastasis of hepatocellular carcinoma (HCC). METHODS: Flow cytometry and immunohistochemistry were used to detect the expression of E-selectin and its ligand-sLeX in HCC cell lines and in human HCC tissues. RESULTS: The positive rate of E-selectin in vascular endothelial cells adjacent to cancer nest in tumors was 67.9% (19/28). In tumors accompanied with emboli or satellite foci, it was significantly higher than that without emboli or satellite foci (P < 0.05). The positive rate of E-selectin was not related to tumor size, tumor capsule, AFP, and the degree of differentiation. The positive expressions of sLeX in SMMU-7721, PLC/PRF/5 and HepGII cell lines were 7.03%, 63.35% and 97.29% respectively. The positive cells of sLeX were mainly distributed in the margin of tumors; the positive expression of sLeX in HCC cells in emboli or invasive tumor tissues was much higher than that in primary foci. CONCLUSION: E-selectin and its ligand-sLeX are closely correlated with the metastasis of HCC.

Adult↗

PubMed2000

[Relationship between tumor suppressor gene p16 and Rb and early diagnosis of lung cancers].

OBJECTIVES: To study the incidences and mechanisms of tumor suppressor gene p16 and Rb inactivation in lung cancers, and to investigate their relation to biological characters, clinical pathological diagnosis and gene classification diagnosis of lung cancers. METHODS: Immunohistochemistry, double in situ hybridization, PCR, PCR-SSCP and sequencing were applied to study the changes of p16 and Rb genes in 106 lung cancers and 23 lung tissues of benign diseases. RESULTS: Total expression rates of p16 and Rb proteins and mRNAs in lung cancers were lower than those in normal lung tissues and benign lung diseases, and they were specially related to histological type, metastasis and clinical stage of lung cancers. In stage I and II lung cancers, the obvious inactivation of tumor suppressor gene p16 or Rb was examined (32.6% or 28.3%); p16 inactivation was detected mainly in non-small cell lung cancers, and Rb inactivation mainly in small cell lung cancers. There were three mechanisms of homozygous deletions, methylations and mutations for p16 gene inactivation. The deletion rate of p16 exon1 and/or exon2 was 25.8%, mainly took place in p16 protein negative cases of non-small cell lung cancers. 15 cases (16.9%) took part in methylations on SmaI sites of CpG island of p16 gene. PCR-SSCP and sequencing showed that 9 cases had p16 gene mutations. CONCLUSIONS: p16 and Rb genes may play important roles in genesis and progression of lung cancers. Inactivation of p16 or Rb gene may be is an early link of lung canceration, that is very important for early diagnosis of lung cancers. A new gene classification model for lung cancer diagnosis would be set up based on the research of p16 and Rb genes.

Adolescent↗

PubMed2000

Relations of tumor suppressor gene p16 and RB to early diagnosis of lung cancer.

OBJECTIVES: To study the incidence and mechanism of the tumor suppressor gene p16 and RB inactivation in lung cancer, and to investigate their relations to biological characteristics, clinical pathological diagnosis and gene classification. METHODS: Immunohistochemistry, double in situ hybridization, PCR, PCR-SSCP, and sequencing were used to study the changes in the p16 and RB genes in 106 patients with lung cancer. The specimen of normal lung tissue from the patients with lung cancer and specimens of the 23 patients with benign lung diseases were studied in contrast to those of the same patients. RESULTS: The total expression rate of the p16 and RB genes in the lung cancer tissues of the 106 patients was lower than that in normal lung tissues and tissues of benign lung diseases and was specially related to histological type, metastasis, and clinical stage of lung cancer. In stage I and II lung cancer, the obvious inactivation rate of the tumor suppressor gene p16 or RB was 32.6% or 28.3%. The p16 inactivation appeared largely in non-small cell lung cancer (50.1%), and the RB inactivation largely in small cell lung cancer (88.2%). Homozygous deletion, methylation, and mutation were three mechanisms for the p16 gene inactivation. The deletion rate of the p16 exon 1 and/or exon 2 was 25.8% in the patients with non-small cell lung cancer. Fifteen patients (16.9%) showed methylation at the SmaI sites of CpG island of the p16 gene. PCR-SSCP and sequencing revealed p16 gene mutation in 9 of the 106 patients with lung cancer. CONCLUSIONS: The p16 and RB genes may play an important role in genesis and progression of lung cancer. The inactivation of the p16 or RB gene may be an early sign of lung canceration, that is important for the early diagnosis. A new gene classification model for lung cancer diagnosis would be set up based on the research of the p16 and RB genes.

DNA Methylation↗

PubMed2000

[Expression of tumor metastasis gene MTA 1 in hepatocellular carcinoma: clinical implications].

OBJECTIVE: To evaluate the relevance of the expression of tumor metastasis gene metastasis-associated 1 (MTA 1) to HCC metastasis. METHODS: A fragment of MTA 1 cDNA was synthesized by reverse transcription (RT)-PCR. A DIG-labeled method of in situ hybridisation (ISH) was used to measure semiquantitatively MTA 1 mRNA in formalin-fixed, paraffin-embedded sections. RESULTS: Most of MTA 1 mRNA positive cells were located on the border of the tumor in some invasive HCC. High MTA 1 expression was found to correlate significantly with portal venous invasion, intrahepatic metastasis, tumor size or distant metastasis (P < 0.05), but not with gender, cirrhosis or AFP level. It also significantly predicted a shorter survival (P < 0.05). CONCLUSION: The overexpression of MTA 1 correlates closely with the invasion process of HCC.

Adult↗

PubMed2000

[Expression of c-fos mRNA following moderate lateral fluid percussion brain injury in rats].

This experiment was designed to study the expression of c-fos mRNA in brain following moderate lateral fluid percussion brain injury in rats and to observe the temporal pattern of its expressions following percussion. Male Sprague-Dawley rats were divided into normal control, sham operation control and injury groups. The rats of the injury group were subjected to moderate lateral fluid percussion injury (0.2 MPa). The injury group was then subdivided into 5 min, 15 min, 30 min, 1 h, 2 h groups according to the time elapsed after injury. The expression of c-fos mRNA was studied with reverse transcription polymerase chain reaction(RT-PCR) semi-quantitatively. c-fos mRNA in cortex and brain stem was expressed weakly in control groups. After 5 min of percussion, the expression of c-fos mRNA increased progressively and remained elevated up to 2 h after brain injury. This result suggested that the induction and expression of the c-fos mRNA in cortex and brain stem after fluid percussion brain injury were increased rapidly. The temporal pattern of induction in cortex was similar to that in brain stem.

Animals↗

PubMed2000

The effect of liposome encapsulated daunorubicin on rabbit eyes after extracapsular lens extraction.

PURPOSE: To investigate the effect of liposome encapsulated daunorubicin (DNR) on rabbit eyes when it was used in prevention of posterior capsule opacification (PCO). METHODS: The liposome encapsulated DNR was prepared by modified freeze-thawing method. Each eye was injected with 0.1 ml liposomes (0.2 mg/ml and 20 micrograms/ml DNR) into the capsular bag during the extracapsular lens extraction (ECLE) in 10 rabbit eyes respectively. The phosphate buffer solution (PBS) was injected as control. Besides biomicroscope observation and histology examination of all eyes, the concentration of DNA in aqueous humor was also determined by high performance liquid chromatography (HPLC). RESULTS: The morphology of liposome encapsulated DNR were similar to the blank liposome with round or ellipse shape. The encapsulated effeciency of liposome encapsulated DNR was 45.1%. The inflammatory response was much more severe both in 0.2 mg/ml and 20 micrograms/ml DNR group than the control after liposome injection. All eyes in DNR group were showed severe corneal edema and opacity and lasted for 4 to 8 weeks. Histopathological study revealed that lens epithelial proliferation occured by 4 weeks and Soemmering's ring developed by 8 weeks in control; However, in DNR group eye only a few LECs remained in the bag and there were obvious corneal edema and eosinophiles infiltration. Corneal endothelial cells were severely lost. CONCLUSION: The results suggest that liposome encapsulated DNR could inhibit metaplasia and proliferation of remnant lens epithelial cells after ECLE in rabbit eyes, but the severe toxicity must be avoided by further study.

Animals↗

PubMed2000

Growth inhibition, induction of apoptosis by green tea constituent (-)-epigallocatechin-3-gallate in cultured rabbit lens epithelial cells.

PURPOSE: To evaluate effect of green tea extract (-)-Epigallocatechin-3-gallate (EGCG) in cultured rabbit lens epithelial cells in order to pave a new way to postcapsular opacity (PCO) prevention. METHODS: Cell survival rate was measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) coloimetric assay. Cell apoptosis was detected by electron microscopy, Hochest 33258 stain and flow cytometer. DNA fragment was detected using agarose gel electrophoresis. RESULT: Proliferation of the cultured rabbit lens epithelia cells was inhibited by EGCG in a dose and time dependent manner. Morphologic study showed that the cells became shrunk, round shaped with their nuclei condensed and broken. Apoptotic bodies were also seen under electron microscope and in Hochest 33258 stain assay 24 hours after EGCG was added to the medium. DNA ladders were shown in agarose gel electrophoresis. In flow cytometry assay, apoptosis peak was also evident. CONCLUSION: Green Tea Constituent(-)-Epigallocatechin-3-gallate could inhibit cultured rabbit lens epithelial cells proliferation by inducing their apoptosis in the concentration used by us, which indicates that it is possible to prevent PCO by using herb extract.

Animals↗