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L Wang

Publications and source records attributed to L Wang.

At least 1,549 records · Page 86Linked to original sources
PubMed1997

[Optimum time of maternal blood sampling for prenatal diagnosis with fetal cells].

OBJECTIVE: To investigate the optimum time of maternal blood sampling for prenatal diagnosis with fetal cells. METHODS: Zinc-finger protein gene on Y-chromosome (ZFY) sequences were examined by nested polymerase chain reaction in the peripheral blood of 41 pregnant women. RESULTS: 19 pregnant women carrying male fetuses, and another 22 women found to carry female fetuses. Among the 19 pregnant women, ZFY gene were detected in 1/19 (5.3%) cases before the 6th gestational weeks, in 13/19 (68.4%) before the 11th weeks, and in 18/19 (95.0%) before the 14th weeks. The results of this study clearly demonstrated that the gender prediction obviously increased along with the gestational weeks. ZFY gene was not detected in the blood of another 22 women carrying female fetuses. The final accuracy of 97.8% (40/41) was attained in all cases. CONCLUSION: The optimum time of maternal blood sampling is at the 14th week, and the appearance of fetal cells in maternal blood was quite case-variable from the 6th to 14th weeks.

Adult↗
PubMed1997

[Influence of antisense N-ras 1 gene on smooth muscle cell proliferation after arterial injury].

OBJECTIVES: To develop a new way to prevent the process of restenosis after arterial injury, we transfered the recombinant antisense N-ras 1 gene to the iliac arteries of rabbits after injury and studied the influence of gene therapy with antisense N-ras 1 on the vascular segment. METHODS: The constructed recombinant antisense N-ras 1 gene to deliver into the iliac arteries of rabbits after injury. The rabbits were randomly divided into gene therapy group, vector group, and sense N-ras 1 control. The segments of treatment rabbits were analysed by angiography of vessels, pathological study, Northern blotting, and Western blotting technique. RESULTS: The minimum angiographic lumen diameter measured during gene therapy and at follow-up, for the gene therapy group (at 4 weeks) was 0.80 +/- 0.10mm and the vector control 0.35 +/- 0.13mm (P < 0.01). Histologically, the area of neointima measured, for gene the therapy group (at 4 weeks) was 0.43 +/- 0.05mm2, and the vector control group 0.82 +/- 0.03mm2 (P < 0.01). By using Northern blotting and Western blotting technique, we found that cell's ras mRNA of the vessel segments of gene local delivery was significantly lower than that of the control. Cell's p21 was significantly lower than that of the control. CONCLUSIONS: The antisense N-ras 1 inhibites VSMC proliferation. The result implicates the potential value in future gene therapy of restenosis.

Angioplasty, Balloon↗
PubMed1997

[Comparison of misoprostol and ricinus oil meal for cervical ripening and labor induction].

OBJECTIVE: To compare the safety and efficacy of intravaginal prostaglandin E1, misoprostol with ricinus oil meal for labor induction. METHODS: Sixty patients with an indication for induction of labor were randomly assigned to two groups (30 cases each) induction with misoprotol, 50 micrograms intra-vaginally every 3 hours until active labor, or with that ricinus oil meal was taken. RESULTS: The time from start of induction to vaginal delivery was significantly shorter in the misoprostol group (12.2 vs 18.1, P < 0.05), and fewer patients in the misoprostol group required oxytocin augmentation (10.0% vs 40.0%, P < 0.05). The mean change in the Bishop score was significantly higher in those receiving misoprostol (5.5 vs 3.1, P < 0.05). Uterine tachysystole occurred more frequently in patients in the misoprostol group (16.7%) than in the ricinus oil meal group (3.0%). No significant differences were noted in the mode of delivery and patients of successful labor induction. CONCLUSIONS: Vaginally administered misoprostol is an effective agent for the cervical ripening and induction of labor.

Abortifacient Agents, Nonsteroidal↗
PubMed1997

Color Doppler imaging diagnosis of intra-ocular tumor.

OBJECTIVE: To demonstrate the color Doppler imaging (CDI) of intra-ocular tumors and its importance in the diagnosis of these tumors. METHODS: Ninety-two patients with intra-ocular tumors (105 eyes) were examined by using CDI to observe the vasculature of these tumors, and using SAS soft ware to analyze the results. RESULTS: Blood flow signal was found in retinoblastoma, melanoma of choroid, angioma of choroid, angioma of optic disc, Coats' disease, persistent hyperplastic primary vitreous (PHPV) and metastatic tumors of choroid, but not found in choroid osteoma and melanocytoma of optic disc. The blood flow decreases in central retinal artery in choroidal melanoma and also in ophthalmic artery, central retinal artery and posterior ciliary artery in angioma of choroid (P < 0.01). It was found that blood velocity is much faster in choroidal melanoma than in choroidal angioma (P < 0.05). CONCLUSIONS: CDI is very important and helpful in the diagnosis of intra-ocular tumors.

Adolescent↗
PubMed1997

Analysis of tumor specific immunoglobulin gene rearrangement in peripheral blood B-cells of multiple myeloma patients by a PCR-SSCP method.

OBJECTIVE: To analyze the clonal relationship between lymphocytes in peripheral blood (PB) and myeloma cell in bone marrow (BM) for proving the existence of circulating tumor cells in multiple myeloma (MM) patients. METHODS: Eighteen patients with MM who have no cytomorphologic plasma cells and CyIg+ cells in PB demonstrated by anti-kappa and anti delta MoAbs using ABC method were involved in the present study, including 3 cases in phases I-II and 15 cases in phase III. The complementary determining region 3 (CDR3) of immunoglobulin heavy chain (IgH) gene was amplified by polymerase chain reaction (PCR). We further analysed the single strand conformation of the PCR products by single strand conformation polymorphism (SSCP) analysis to detect the mononuclear cells in PB and BM of the patients simultaneously. RESULTS: The same PCR products of IgH-CDR3 gene with BM samples were found in PB of 11 MM patients. The same PCR products and single strand conformation in both PB and BM were found in 9 cases. CONCLUSIONS: This study has proved the presence of identical clonal malignant cells in PB and BM of MM patients. B cells are involved in the pathogenesis of MM.

Adult↗
PubMed1997

[The relationship between the pathologic features of the uninvolved endometrium and prognosis in postmenopausal endometrial carcinoma].

OBJECTIVE: To investigate the relationship between the pathologic features of the uninvolved endometrium and prognosis in postmenopausal endometrial carcinoma. METHOD: The clinicopathologic features of 204 cases of endometrial carcinoma were analyzed retrospectively, according to the proliferative and atrophic uninvolved endometrium, a long term follow-up was done. RESULTS: The patients with proliferative uninvolved endometrium (PUE) were more much related with the clinical risk factors than those of atrophic uninvolved endometrium (AUE) (P < 0.001). AUE cases had more virulent types of nonendometrial carcinoma than those of PUE (27% vs 5.5%, P < 0.001), and had much worse grade, much deeper myometrial invasion and much vascular invasion (P < 0.001). The overall 5-year survival rate was 96.7% in the PUE cases and 86.2% in the AUE cases (P < 0.001). CONCLUSION: The histopathologic types of the uninvolved endometrium were related to the prognosis of the patients with endometrial carcinoma. The patients with proliferative uninvolved endometrium had better prognosis than those with atrophic uninvolved endometrium.

Adenocarcinoma↗
PubMed1997

[The development of CTTM-1000 distant electrocardiogram central ambulatory monitoring system].

This article introduces a new electrocardiogam telephone transmitting and central ambulatory monitoring (receiving) system, and a device used for monitoring and transmitting the user's electrocardiogram. We also give some detailed discussion about the real time the flow display of ECG, and the signal preprocessing method based on the design of optimum FIR linear phase digital filter for the detection of QRS complexes.

Electrocardiography, Ambulatory↗
PubMed1997

[Prevalence of Helicobacter pylori(Hp) infection in the department of gastroenterology staff members in Nanjing].

The present study was carried out by measuring anti-Hp IgG in peripheral blood from fingers. Two hundred and thirty-two subjects working in six hospitals in Nanjing were investigated, including 102 gastroenterologists and gastroenterology nurses (G group), 130 nongastroenterology practioners (NG group). RESULTS SHOWED: (1) Optical density level of G group (0.71 +/- 0.29) was significantly different from that of NG group (0.49 +/- 0.28) (P < 0.005); (2) Among G group: doctors compared with nurses (P > 0.05); endoscopists compared with general practioners (P > 0.25); among three subgroups, divided by their working years in gastroenterology field or endoscopy room as less than 5 years, 5-10 years or more than 10 years, with no significant differences. CONCLUSIONS: (1) Department of Gastroenterology staff members have a higher risk of Hp infection than other groups in hospitals. (2) The risk of gastroenterologists or gastroenterology nurses infected by Hp would reach maximum after 5 years of working. (3) Using gloves in clinic practice might reduce the incidence of Hp infection.

Adult↗
PubMed1997

[The detection of Legionella pneumophila DNA with polymerase chain reaction in water samples].

Legionella pneumophila has been known as an important pathogen causing Legionnaires Disease (LD), responsible for more than 80 per cent of clinical LD cases and majority of the LD outbreaks. In order to detect the existence of Legionella pneumophila strains in water samples, we have developed a ploymerase chain reaction method, using two primers synthesized according to the reported Legionella pneumophila mip gene nucleotide sequence. This method was proved to be highly sensitive (18 cfu/ml) and specific. Two water samples were detected positive. This newly developed method provided a quick, accurate way not only to detect Legionella pneumophila in the diagnosis of LD but also in the capture of suspected pathogen during epidemiologic investgation when LD outbreaks.

Air Conditioning↗
PubMed1997

[Effects of cigarette smoke on allergic diseases].

Reactions were determined in 1,606 patients with allergic diseases by specific skin test in vivo, using cigarette smoke as allergen, to study its effects on the diseases. Relationship between positive skin reaction, kinds of allergic diseases, and age and sex of the patients was analyzed with multiple regression. Results showed that proportion of positive skin reaction accounted for 34.5 percent (with 556 cases), and positive skin reaction correlated with the occurrence of allergic diseases, but did not with the age, sex, length of the course of the patients and counts of peripheral white blood cell and eosinophil cell. Airway challenge test with acetylmethylcholine was conducted in 58 patients of bronchial asthma with positive skin reaction. Their forced vital capacity (FVC), forced expiratory volume in one second (FEV1) and peak expiratory flow rate (PEFR) after provocation were lower than those before it. Serum levels of total IgE were determined with ELISA in 223 cases (184 cases with bronchial asthma, 87 allergic rhinitis, and 52 allergic skin diseases) with positive skin reaction, and their serum total IgE level was significantly increased, as compared with the controls.

Adolescent↗
PubMed1997

[Involvement of nitric oxide and cGMP in the protective effect of neurotensin on hepatocytes].

In the present work, the relation of cytoprotection of neurotensin to nitric oxide (NO), cGMP and cAMP was investigated in primary cultured mouse hepatocytes. The results are as follows: After administration of acetaminophen (20 mmol/L) to the medium, the leakage of GOT and GPT increased significantly. Pretreatment with neurotensin (10(-7) mol/L) before acetaminophen reduced the leakage of GOT and GPT. No synthase inhibitor, L-NAME, completely blocked the cytoprotective effect of neurotensin. Neurotensin could enhance the intracellular cGMP content, but had no effect on cAMP content. These results indicate that the protective effect of neurotensin on hepatocytes is mediated by NO probably by enhancing intracellular cGMP content.

Acetaminophen↗
PubMed1997

5-Fluorouracil interferes with paclitaxel cytotoxicity against human solid tumor cells.

Paclitaxel, a naturally occurring antimitotic agent, has shown efficacy in the treatment of certain solid tumors, particularly metastatic breast carcinoma and drug-refractory ovarian cancers. Recent studies have demonstrated that paclitaxel, in addition to its effects on microtubules and cell cycle arrest, possesses significant cell-killing activity in solid tumor cells by the induction of apoptosis. However, the mechanism by which paclitaxel leads to cell death and its relationship with paclitaxel-induced mitotic arrest is presently unclear. In this study, we attempted to determine whether pre-arresting tumor cells at other phases of the cell cycle could affect paclitaxel-induced apoptosis. We found that 5-fluorouracil (5-FU), another antineoplastic agent that usually arrests tumor cells at the G1-S phase of the cell cycle, could significantly repress the cell-killing activity of paclitaxel in solid tumor cells, even when it was added simultaneously with paclitaxel. Further studies indicated that 5-FU actually inhibits the cytotoxic effects of paclitaxel on both mitotic arrest and apoptotic cell death, suggesting that 5-FU might interfere with paclitaxel cytotoxicity at an early stage, probably by preventing tumor cells from entering G2-M phase. Because recent clinical trials have used a combination of paclitaxel and 5-FU in the treatment of metastatic breast cancers, our results also suggest that the combination of these two drugs might not be as valuable in clinical chemotherapy.

Antimetabolites, Antineoplastic↗
PubMed1996

The TAF(II)250 subunit of TFIID has histone acetyltransferase activity.

The transcription initiation factor TFIID is a multimeric protein complex composed of TATA box-binding protein (TBP) and many TBP-associated factors (TAF(II)s). TAF(II)s are important cofactors that mediate activated transcription by providing interaction sites for distinct activators. Here, we present evidence that human TAF(II)250 and its homologs in Drosophila and yeast have histone acetyltransferase (HAT) activity in vitro. HAT activity maps to the central, most conserved portion of dTAF(II)230 and yTAF(II)130. The HAT activity of dTAF(II)230 resembles that of yeast and human GCN5 in that it is specific for histones H3 and H4 in vitro. Our findings suggest that targeted histone acetylation at specific promoters by TAF(II)250 may be involved in mechanisms by which TFIID gains access to transcriptionally repressed chromatin.

Acetyltransferases↗
PubMed1996

Tolerance to rat liver allografts: IV. Acceptance depends on the quantity of donor tissue and on donor leukocytes.

Liver allografts in some rat strains are often spontaneously accepted across a complete major histocompatibility barrier without the requirement for immunosuppression while other nonliver allografts are rejected. In previous studies, we have shown that spontaneous acceptance is dependent on liver passenger leukocytes. Depletion of passenger leukocytes by donor irradiation allows rejection, with DA recipients of irradiated PVG livers having a median survival time (MST) of 16 days. Here we show that, in this model, spontaneous acceptance is reconstituted by intravenous injection of donor leukocytes. Intravenous injection of 3-5x10(7) PVG liver leukocytes significantly prolonged DA survival time (MST=96 days, P=0.026), as did 5x10(7) spleen leukocytes (MST>100 days, P=0.002). Deletion of T cells from the reconstituting inoculum reduced survival time (MST=78 days, P=0.039), whereas deletion of B cells or monocytes/macrophages had no effect on survival time. In contrast, PVG hearts are regularly rejected by DA recipients, and PVG liver or spleen leukocytes, even at doses of greater than 3x10(8) cells/recipient, were unable to induce heart acceptance. To investigate the possibility that acceptance of the irradiated liver but not the heart might be due to the large mass of the liver, two kidneys and two hearts of PVG origin were transplanted to each DA recipient together with 1.5x10(8) PVG leukocytes. These organs survived for greater than 200 days, thereby showing that a large mass of donor tissue, in association with donor leukocytes, leads to acceptance of organs that are rejected if transplanted singly. It appears likely that spontaneous liver transplant tolerance is a high-dose or activation-associated immune phenomenon.

Animals↗
PubMed1996

Insulin-stimulated translocation of GLUT4 glucose transporters requires SNARE-complex proteins.

A major physiological role of insulin is the regulation of glucose uptake into skeletal and cardiac muscle and adipose tissue, mediated by an insulin-stimulated translocation of GLUT4 glucose transporters from an intracellular vesicular pool to the plasma membrane. This process is similar to the regulated docking and fusion of vesicles in neuroendocrine cells, a process that involves SNARE-complex proteins. Recently, several SNARE proteins were found in adipocytes: vesicle-associated membrane protein (VAMP-2), its related homologue cellubrevin, and syntaxin-4. In this report we show that treatment of permeabilized 3T3-L1 adipocytes with botulinum neurotoxin D, which selectively cleaves VAMP-2 and cellubrevin, inhibited the ability of insulin to stimulate translocation of GLUT4 vesicles to the plasma membrane. Furthermore, treatment of the permeabilized adipocytes with glutathione S-transferase fusion proteins encoding soluble forms of VAMP-2 or syntaxin-4 also effectively blocked insulin-regulated GLUT4 translocation. These results provide evidence of a functional role for SNARE-complex proteins in insulin-stimulated glucose uptake and suggest that adipocytes utilize a mechanism of regulating vesicle docking and fusion analogous to that found in neuroendocrine tissues.

1-Methyl-3-isobutylxanthine↗