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Biomedical subjects

Yang Wang

Publications and source records attributed to Yang Wang.

At least 145 records · Page 8Linked to original sources
PubMed2005

[Determination of nitrite in water samples by sequential injection analysis with chemiluminescence detection on chip flow cell].

A sequential injection chemiluminescence's system using a chip flow cell was described for the determination of trace amount of nitrite in water samples. Nitride reacted with hydrogen peroxide to form peroxynitrous acid in sulfuric acid medium, which was an unstable in acid medium and subsequently was quenched into peroxynitrite in basic solution. During the composition of peroxynitrite the chemiluminescence intensity was enhanced with the presence of uranin and ethyldimethylcetylammonium bromide. The reaction coil (flow cell) and holding coil was combined for tracking the emission signal. The experimental parameters including physical and chemical parameter were optimized. The interference of cations in water samples was eliminated by passing previously the sample solution through a cation-exchange column. The linear range of the calibration graph was obtained from 1 x 10(-6) to 1 x 10(-4) mol x L(-1) with a correlation coefficient of 0.9998. The detection limit at 95% confidence was 6.8 x 10(-7) mol x L(-1). The relative standard deviation at 1 x 10(-5) mol x L(-1) nitrite level was 2.7%, and the recovery of 90%-99% and the sampling frequency of 80 h(-1) were obtained.

Calcium↗
PubMed2005

[Accumulation of La(NO3)3 in mice liver and its genetic toxicity].

By using ICP-MS method, this paper determined the accumulation of La in mice liver after the mice being fed with La(NO3)3 water solution for thirty days, and through in vitro experiment, studied the effect of La(NO3)3 on the micronucleus rate of mice bone marrow cells and the cleavage action of La(NO3)3 on genome DNA to investigate the genetic toxicity of La. The results showed that when the treated concentration was 1000, 500, 300 and 50 microg x ml(-1), the amount of La in mice liver reached 1.46, 0.558, 0.529 and 0.083 microg x g(-1), respectively. Compared with control, the La amount in disposed groups' mice livers increased with increasing La(NO3)3 concentration in water (r = 0.980). T-test results showed that there existed significant differences in 1000, 500 and 300 microg x ml(-1) disposed groups when compared with the control (P < 0.05). The micronucleus rate of mice bone marrow cells increased with increasing La(NO3)3 concentration in water (r = 0.853). The in vitro experiments showed that La(NO3)3 could make DNA cleaved. It could be concluded that that La might be accumulated in organisms, and could induce the damage of genetic material in cells.

Animals↗
PubMed2005

[Activation of Kupffer cell TLR2 signaling pathway during hepatic ischemia/reperfusion injury process in mice and it's significance].

OBJECTIVE: To study changes of TLR2 signaling pathway expression in Kupffer cells during the process of hepatic ischemia/reperfusion in a mice model and the mechanism of TLR2 signaling pathway participating in hepatic ischemia/reperfusion injury. METHODS: BALB/c mice were divided into 3 groups: sham operation (SH), ischemia/reperfusion (I/R) and GdCl3 treatment (Gd) groups. After 4 h of reperfusion, the expression of TLR2 mRNA and membrane TLR2 protein were analyzed in ischemic lobes of the livers, and in Kupffer cells isolated from ischemic lobes. The expression of NF-kappaB in ischemic lobes was also examined. Levels of endotoxin, ALT and TNFalpha were measured at the same time point. RESULTS: The expressions of TLR2 mRNA and protein in both ischemic hepatic lobes and Kupffer cells isolated from ischemic lobes were increased in the I/R group compared to those in the SH group, as well as the expression of NF-kappaB in ischemic lobes, which was down regulated by intravenous GdCl3 treatment. Levels of ALT and TNFalpha in the portal vein were higher in the I/R group than in the SH group, which also were decreased with treatment of GdCl3. The level of endotoxin in the three groups remained constant. CONCLUSION: TLR2 signaling pathway in Kupffer cells is activated during the process of hepatic ischemic/reperfusion injury. The activation of TLR2 signaling pathway in Kupffer cells may play a role in this process.

Animals↗
PubMed2005

[Expression of aurora-A kinase in human lung cancer cell lines PG, A549, and NCI-H460].

BACKGROUND & OBJECTIVE: Recent researches found that Aurora-A overexpresses in various malignancies. This study was to detect the expression of Aurora-A in lung cancer cell lines PG (highly-metastatic giant cell lung cancer), A549 (lung adenocarcinoma), and NCI-H460 (large cell lung cancer) and explore its correlation to DNA content, provide a theoretical basis for screening tumor marker and molecular therapeutic target of lung cancer. METHODS: mRNA and protein levels of Aurora-A in PG, A549, and NCI-H460 cells were detected by reverse transcription-polymerase chain reaction(RT-PCR) and Western blot. Flow cytometry was used to analyze DNA contents in cell cycles of PG, A549, and NCI-H460 cells. RESULTS: mRNA level of Aurora-A was 1.14 in PG cells, 1.16 in A549 cells, and 0.84 in NCI-H460 cells, respectively; protein level of Aurora-A was 8.96 in PG cells, 21.13 in A549 cells, and 6.43 in NCI-H460 cells, respectively. The proportion of cells with tetraploid DNA was 19.88% in PG cells, 14.97% in A549 cells, and 10.6% in NCI-H460 cells, respectively (P<0.01); the proportion of cells with polyploid DNA was 2.66% in PG cells, 3.59% in A549 cells, and 2.30% in NCI-H460 cells, respectively. CONCLUSION: Aurora-A is overexpressed in the 3 lung cancer cell lines, but the mRNA levels are different.

Adenocarcinoma↗
PubMed2005

[A new technique of upper-middle face rhytidectomy without destroying the configuration of sideburn].

OBJECTIVE: To introduce a safe, effective and lasting rhytidectomy technique without destroying the configuration of sideburn. METHODS: The operation is performed through the coronal incision, the temporal incision that is paralleled to the nasolabial sulcus, and the preauricular incision in the sideburn. Multi-layer dissection of facial tissue is made. RESULTS: 46 patients with aging face have been treated using this technique since 2002. All patients obtained good curative effects without any severe complications. CONCLUSIONS: This operation technique may maintain the natural configuration of the preauricular area and sideburn, result obscure incision scar and avoid harming important nerves or vessels. Multi-layer dissection accords with anatomical principles and produces a lasting curative effect.

Adult↗
PubMed2005

[Effect of anti-TGF-beta antibody on ex vivo expansion and expression of adhesion molecules of human cord blood CD34+ cells].

TGF-beta, as an inhibitor of hemopoiesis, excreted by hematopoietic stem and progenitor cells, down-regulates the expression of cytokines such as Flt-3 ligand, SCF, IL-3 etc on the stem and progenitor cells. The effect of anti-TGF-beta antibody on ex vivo expansion and expression of adhesive molecules on cord blood CD34(+) cells was studied in this research. The CD34(+) cells from six units of fresh umbilical cord blood were enriched by density gradient sedimentation and purified by miniMACS cell isolation system, and plated them into the SFEM serum free culture system which containing SCF, Flt-3L, TPO and IL-3 in the condition of 37 degrees C, 5% CO2, and saturated moisture. There were three groups in this experiment: (1) blank group: same as the culture system described above; (2) control group: added with normal rabbit IgG into the mentioned culture system; (3) test group: the same culture system with anti-TGF-beta1 antibo-dy. Cultured for 6 days, the number of mononuclear cells (MNC) was counted, the expression of CD34 antigen, CD117 (c-kit) antigen, CD11a antigen, CD49d antigen and CD33 antigen was tested with FCM. Meanwhile, cells of the three groups were plated in the methylcellulose culture system for 14 days, the number of CFU-GEMM, BFU-E, CFU-GM was counted. The results indicated that the expansion multiples of MNC, CD34(+) cells, CD34(+)c-kit(+) cells, CFU-GEMM in the test group (41.82 +/- 13.49, 15.62 +/- 6.95, 13.36 +/- 6.12, 11.07 +/- 4.05) were significantly higher than in the control group (28.86 +/- 9.03, 10.40 +/- 4.98, 9.04 +/- 4.40, 6.36 +/- 2.37) (P = 0.001, 0.002, 0.003, 0.002) respectively. The expansion multiple of more primitive CD34(+)c-kit(-) subpopulation in the test group (69.10 +/- 41.06) was even higher than in the control group (27.29 +/- 10.40) (P = 0.024). Adhesion molecule expression on the CD34(+) cells after short-term expansion: the expression of CD11a on the CD34(+) cells of the original cord blood was (61.73 +/- 4.13)%, and CD49d was (55.12 +/- 5.22)%. After expansion in each group the expression of CD11a on the CD34(+) cells did not change with statistical significance (P > 0.05), the expression of CD49d increased (P < 0.05). Compared with blank group and control group, anti-TGF-beta antibody did not impact on the expression of CD11a and CD49d (P > 0.05). It is concluded that anti-TGF-beta antibody can synergize other cytokines to effectively enhance the proliferation of cord blood NC, CD34(+) cells, progenitor subpopulation of CD34(+)c-kit(-) cells, and increase the output of more primitive progenitor colony, CFU-GEMM and BFU-E. At the same time, anti-TGF-beta antibody did not depresss the expression of adhesion molecules on CD34(+) cells.

Antibodies↗
PubMed2005

Differentiation of human bone marrow stromal cells into neural-like cells induced by sodium ferulate in vitro.

Human marrow stromal cells (hMSCs) are multipotential stem cells, capable of differentiating into bone, cartilage, fat and muscle. Several recent reports demonstrated that hMSCs have been also differentiated into neural cells. However, only a few reported inducers are applicable for clinical use. This work is to explore the effects of sodium ferulate (SF) on differentiation of hMSCs into neural cells in vitro. We found that hMSCs could be induced to the cells with typical neural morphology when cultured with SF. The cells express neural proteins, such as nestin, neuron-specific enolase (NSE) and glial fibrillary acidic protein (GFAP). About 30% of the hMSC-derived cells expressed nestin when cultured with SF for 3 h, but no expression was detected after 24 h. The percentages of positive cells for NSE or GFAP were about 67% and 39% separately at 6 h, and reached the plateau phage after treatment with SF for 3 days. The data suggest that SF can induce hMSCs to differentiate into neural-like cells in vitro.

Biomarkers↗
PubMed2005

[The detection of human papilloma virus in juvenile-onset respiratory papillomatosis].

OBJECTIVE: To investigate the relationship between juvenile-onset respiratory papillomatosis (JOP) and human papilloma virus (HPV6, HPV11), and the immune function of patients. METHOD: Fluorescence quantitative PCR (FQ-PCR) which combines PCR and fluorescence probe hybridization was used to detect HPV6 , HPV11 DNA in 130 cases. Of these, 68 cases were used Flow Cytometry to measure CD3, CD4, CD8. RESULT: One hundred and fifteen of 130 cases were HPV6, HPV11 DNA positive, the average copy was 5.68 +/- 2.65. For 68 cases,the average percent of CD3,CD4,CD8 were 62.73 +/- 8.63, 30.54 +/- 7.05, 26.08 +/- 6.93, respectively. To compare with control group, there was not statistical significance. CONCLUSION: FQ-PCR is a convenient, accurate and specific method which can quantify the amount of pathogenic germs from 10(1) to 10(10), and is also a reliable factor to predicate clinical diagnose and cure.

Adult↗
PubMed2005

[The periareolar approach management of postoperative complications of breast augmentation by injected polyacrylamide hydrogel].

OBJECTIVE: To analysis various complications of 30 patients of breast augmentation by injected polyacrylamide hydrogel and discuss the treatment through periareolar incision. METHODS: All patients were classified according to the different complications. Open suction technique and partial mastectomies via periareolar incisions were performed in all patients, Only one patient had immediately breast reconstruction with prosthesis, five patients received secondarily breast prostheses implantation via a axillary incision. RESULT: All the symptoms were relieved after remove of polyacrylamide hydrogel. CONCLUSIONS: Polyacrylamide hydrogel should be prohibited for injected breast augmentation at present. A double-blinded randomized clinical study, controlled animal experiments and a large sample questionnaire survey for complications are necessary. The periareolar approach is valuable technique and can remove polyacrylamide hydrogel as completely as possible.

Acrylic Resins↗
PubMed2004

A novel cancer therapy: combined liposomal hypoxia inducible factor 1 alpha antisense oligonucleotides and an anticancer drug.

The combined influence of doxorubicin (DOX) and liposomal antisense oligonucleotides (ASOs) targeted to hypoxia-inducible factor 1 alpha (HIF1A) subunit on the apoptosis signaling pathways and cellular pump and nonpump resistance were investigated. Drug-sensitive A2780 and multidrug-resistant A2780/AD human ovarian carcinoma cells were used. Cells were incubated within 48h in normoxic (21% O(2), 5% CO(2) and 74% N(2)) or hypoxic (1% O(2), 5% CO(2) and 94% N(2)) conditions, with or without DOX in the concentration corresponding to the IC(50) dose, with or without liposomal ASO targeted to HIF1A mRNA. Apoptosis induction, lactic acid concentration, expression of genes and proteins involved in apoptosis signaling pathways, pump and nonpump cellular resistance were assessed. The results showed that overexpression of HIF1A protein induced by exposure to hypoxia and DOX activated both apoptotic cellular signal and cellular antiapoptotic defense. In addition, while hypoxia suppressed cellular pump resistance, due to multidrug resistance-associated protein family transporters, DOX activated pump resistance. A decrease in the expression of targeted protein (HIF1A) by liposomal HIF1A ASO effectively suppressed pump and nonpump cellular resistance and significantly enhanced apoptosis induction by hypoxia and DOX. Data obtained showed that ASO targeted to HIF1A mRNA that suppress cellular antihypoxic defense might be used as a powerful tool to improve the anticancer action of cytotoxic drug or even as an anticancer agent.

Apoptosis↗
PubMed2004

Coronary bypass before simultaneous pancreas-kidney transplants for type 1 diabetics in renal failure.

Our study examined the results of coronary artery bypass (CAB) before simultaneous pancreas-kidney (SPK) transplant in type 1 diabetics in renal failure. Of 588 pancreas transplant patients from 1992 to 2002, 77 (24 females, 53 males) were candidates for SPK transplant. All 77 had coronary evaluation and were referred for pretransplant CAB. Among the 77 CAB patients, the mean age was 42 years (range: 30- 63 years), and the duration of diabetes was 28.52 years (range: 9-51 years). All had neuropathy, retinopathy, and nephropathy; 12.9% (n = 10) had angina; and 76% (n = 59) were on dialysis at the time of CAB. The creatinine level of the 18 nondialysis patients was 3.7 mg%; 42.8% (n = 33) had suffered myocardial infarction. The left ventricular ejection fraction (LVEF) was 49% (30-65%). At CAB surgery, 88% (n = 68) triple, 9% (n = 7) double, and 2.5% (n = 2) single arterial grafts were implanted. All 77 CAB patients had severe coronary artery disease (CAD); some vessels could not be bypassed in 9.8%. At surgery, 3.4 grafts/patient were implanted (range: 1-6 grafts). All 59 dialysis patients continued dialysis after CAB; 6 nondialysis patients required dialysis after CAB. The intensive care stay averaged 1.86 days (range: 1-10 days); the hospital stay averaged 10.5 days (range 6-28 days). There was no operative mortality. Eventually, 68 patients underwent SPK transplant; 9 await organs. The waiting period for 68 CAB patients who had SPK was 2 years, 5 months (range: 2 months to 10 years). The SPK operative mortality was 3.9% (n = 3). Significant CAD exists in patients > 30 years of age with type 1 diabetes and renal failure. Pretransplant CAB can be done safely and may reduce posttransplant mortality associated with cardiac events.

Acute Kidney Injury↗
PubMed2004

Late-course accelerated hyperfractionated radiotherapy for localized esophageal carcinoma.

PURPOSE: To evaluate the long-term survival results and patterns of failure for localized carcinoma of the esophagus receiving late-course accelerated hyperfractionated (LCAF) radiotherapy (RT). METHODS AND MATERIALS: We studied 201 patients with histologically confirmed squamous cell carcinoma of the esophagus who were treated with LCAF RT between August 1994 and January 2000. The design of the radiation fields was based on the diagnosis by computed tomography and barium examination. All patients received conventionally fractionated RT at 1.8 Gy/d, five fractions weekly for the first two-thirds of treatment to a dose of about 41.4 Gy in 23 fractions within 4-5 weeks. This was followed by LCAF RT using reduced fields, 1.5 Gy/fraction twice daily with a 6-h interval between fractions, to a dose of about 27 Gy within 9 days. Thus, the total dose was 68.4 Gy in 41 fractions within 44 days. RESULTS: The incidence of Grade 3-5 acute radiation-induced bronchitis was 4.0% (8 cases), 3.0% (6 cases), and 0%, respectively. The incidence of Grade 3-5 acute radiation-induced esophagitis was 14.9% (30 cases), 0.5% (1 case), and 0%. Ten patients (5%) died of late complications. The 1-year, 3-year, and 5-year overall survival rate was 73%, 34%, and 26%, respectively. The 1-year, 3-year, and 5-year local control rate was 77%, 58%, and 56%, respectively. The main site of first failure was locoregional failure and distant metastasis (including lymph node metastasis from regional recurrence). Of 201 patients, 77 (38.4%) had local disease alone or with distant metastasis as the first failure, and 70 patients (34.9%) had distant metastasis and/or lymph node metastasis alone or with local failure as the first failure. CONCLUSION: The LCAF regimen offers similar local control and survival to standard chemotherapy plus RT, such as was delivered in the Radiation Therapy Oncology Group studies 85-01 and 94-05.

Adult↗
PubMed2004

Enhancement of the efficacy of chemotherapy for lung cancer by simultaneous suppression of multidrug resistance and antiapoptotic cellular defense: novel multicomponent delivery system.

The efficacy of chemotherapy of lung cancer is limited by the development of resistance in cancer cells during treatment. In most lung cancers, this resistance is associated with the overexpression of (a) multidrug resistance-associated protein (MRP) responsible for drug efflux from the cancer cells (pump resistance) and (b) BCL2 protein that activates antiapoptotic cellular defense (nonpump resistance). A novel liposomal proapoptotic anticancer drug delivery system was developed to enhance anticancer efficacy of the well-established drug doxorubicin (DOX). This multicomponent drug delivery system was tested on multidrug-sensitive and -resistant human small-cell lung cancer cells. The drug delivery system includes four components: (a) liposome as a carrier, (b) DOX as an inductor of apoptosis, (c) antisense oligonucleotides (ASOs) targeted to MRP1 mRNA as a suppressor of pump resistance, and (d) ASOs targeted to BCL2 mRNA as a suppressor of nonpump resistance. Intracellular internalization of ASOs and DOX; the influence of the proposed system on the expression of genes and proteins involved in the multidrug resistance, cytotoxicity, and apoptosis induction and antiapoptotic defense; and the activity of caspases were studied. It was found that the proposed liposomal delivery system successfully delivered ASOs and DOX to cell nuclei, inhibited MRP1 and BCL2 protein synthesis, and substantially increased the anticancer action of DOX by stimulating the caspase-dependent pathway of apoptosis in multidrug-resistant human lung cancer cells.

Apoptosis↗
PubMed2004

[Transplantation of gene-transfected neural stem cells for transient cerebral ischemia in rats].

OBJECTIVE: To detect the expression and the role of vascular endothelial growth factor (VEGF)-transfected neural stem cells (NSCs) in rat brain subjected to ischemia. METHODS: Fetal NSCs were cultured from E14 days SD rats and transfected with VEGF121 gene by using lipofectAMINE technique. The gene expression of transfected cells was detected by RT-PCR and immunofluorescent staining in vitro. Temporary middle cerebral artery occlusion (tMCAO) model was established in 40 SD rats and then rate were randomly divided into (1) control group (n = 10), (2) PBS transplantation group (n = 10), (3) neural stem cells transplantation group (n = 10), and (4) VEGF-secreting neural stem cells transplantation group (n = 10). BrdU-labelled NSCs and VEGF-secreting NSCs were transplanted into the penumbra zones respectively 3 days after the tMCAO model was established. Neurological Severity Score (NSS) was checked in all groups 2, 4, 6, 8, 10, 12 weeks respectively after transplantation. One and 12 weeks after the transplantation, 10 rats in the group (4) were killed and then brains taken out respectively. By using immunofluorescent staining, the VEGF expression of transplanted cells 1 week after transplantation, differentiation and migration of transplanted neural stem cells 12 week after transplantation were detected respectively. RESULTS: VEGF-transfected neural stem cells could continuously express gene products during the first 2 weeks. Both transfected NSCs and their progeny expressed VEGF gene products, which was demonstrated by fluorescence study. There were no significant differences in NSS in groups 4 when tMCAO models were just established. However, the values of NSS in (4) group were 5.8 +/- 1.5, 5.0 +/- 1.0, 4.6 +/- 1.0, 4.0 +/- 0.7, 4.0 +/- 1.0, 3.8 +/- 0.4 from 2 approximately 12 weeks after transplantation, significantly lower than those in groups (1) and (2) 8 weeks (P = 0.008) and those in groups (1), (2) and (3) 12 weeks (P = 0.000) after transplantation. NSS in group (3) was also lower than that in groups (1) and (2) 8 and 12 weeks after transplantation. One week after transplantation, immunofluorescent staining showed that VEGF-transfected NSCs migrated and expressed VEGF into hosts' brains. Twelve weeks after transplantation, transplanted NSCs survived and migrated, some of them differentiated to neurons and integrated well with hosts' cytoarchitectural components. CONCLUSION: VEGF-transfected NSCs express gene products during the early time after transplantation, which reduce brain injury through protecting the vascular system against ischemia and reperfusion injury. Transplantation of VEGF-transfected NSCs might be a novel method for treatment of cerebral ischemia.

Animals↗
PubMed2004

A pattern recognition serine proteinase triggers the prophenoloxidase activation cascade in the tobacco hornworm, Manduca sexta.

A serine proteinase cascade in insect hemolymph mediates prophenoloxidase activation, a defense mechanism against pathogen or parasite infection. Little is known regarding its initiating proteinase or how this enzyme is activated in response to invading microorganisms. We have isolated from the tobacco hornworm, Manduca sexta, a cDNA encoding a modular protein designated hemolymph proteinase 14 (HP14). It contains five low density lipoprotein receptor class A repeats, a Sushi domain, a unique Cys-rich region, and a proteinase-catalytic domain. The HP14 mRNA exists in fat body and hemocytes of the naive larvae, and its level increases significantly at 24 h after a bacterial challenge. We expressed proHP14 with a carboxyl-terminal hexahistidine tag in a baculovirus/insect cell system and detected the recombinant protein in two forms. The 87-kDa protein was primarily intracellular, whereas the 75-kDa form was present in the medium. Interaction with peptidoglycan resulted in proteolytic processing of the purified zymogen and generation of an amidase activity. Supplementation of hemolymph with proHP14 greatly enhanced prophenoloxidase activation in response to Micrococcus luteus. These data suggest that proHP14 is a pattern recognition protein that binds to bacteria and autoactivates and triggers the prophenoloxidase activation system in the hemolymph of M. sexta.

Amino Acid Sequence↗
PubMed2004

Differential expression of thyroid-stimulating hormone beta subunit in gonads during sex reversal of orange-spotted and red-spotted groupers.

We have cloned and characterized the full-length cDNA encoding thyroid-stimulating hormone beta-subunit (TSHbeta) from orange-spotted grouper Epinephelus coioides. It contains 913 nucleotides with an open reading frame encoding 146 amino acids with a 20 amino acid signal peptide. The grouper mature TSHbeta has 75, 70, 61, 59, 41, 42 and 40% identities to that of rainbow trout, Atlantic salmon, zebrafish, European eel, chicken, mouse and human, respectively. RT-PCR analysis indicated that the TSHbeta mRNA was expressed abundantly not only in pituitary but also in gonads. A more interesting finding is to reveal the differential TSHbeta expressions between the ovaries and the transitional gonads or testes in natural individuals of orange-spotted grouper and red-spotted grouper Epinephelus akaara, and in artificial sex reversal individuals of red-spotted grouper induced by MT feeding. In situ hybridization localization provided direct evidence that the TSHbeta was transcribed in the germ cells. In the growing oocytes, the TSHbeta transcripts were concentrated on the ooplasm periphery. In testicular tissues, the intensively expressed TSHbeta cells were found to be spermatogonia and spermatocytes in the spermatogenic cysts. This is the first report of a TSHbeta expressed in the gonads of any vertebrates in addition to the expected expression in the pituitary, and it expresses more transcripts in the gonads during sex reversal or testis than in the ovaries both in E. coioides and E. akaara. Importantly, the TSHbeta identification in germ cells allows us to further investigate the functional roles and the molecular mechanisms in gametogenesis of groupers, especially in sex reversal and in spermatogenesis.

Amino Acid Sequence↗