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Biomedical subjects

Wei Chen

Publications and source records attributed to Wei Chen.

At least 451 records · Page 25Linked to original sources
PubMed2003

[Proliferating cell nuclear antigen expression in recurrent aphthous ulcer and its significance].

OBJECTIVE: To explore the expression changes of proliferating cell nuclear antigen (PCNA) in oral normal mucosa and recurrent aphthous ulcers(RAU). METHODS: The expression intensity and distribution of PCNA were examined with immunohistochemistry method in 15 cases of recurrent oral aphthous and normal oral mucosa. RESULTS: In RAU, there was large amount of inflamed cells. In normal oral mucosa, the expression intensity of PCNA was significant higher than that in oral aphthous (P<0.05). CONCLUSION: The inhibition of epidermal cells proliferation in RAU may be one of the mechanisms which one involved in RAU formation.

Case-Control Studies↗
PubMed2003

[Expression of protooncogene c-jun, p38 and proliferating cell nuclear antigen in intestinal epithelial cells in rats different development stages].

OBJECTIVE: To investigate the expression characteristics of protooncogene c-jun and its related gene p38 in different developmental intestinal epithelial cells in rats, and to explore their biological roles in the intestinal wound healing after injury. METHODS: Immunohistochemical techniques were used to detect the expressions of c-jun, p38 and proliferating cell nuclear antigen (PCNA). RESULTS: The positive expression of c-jun in intestinal epithelial cells at the early development stage (from E14 d to P28 d) was much stronger and more extensive than that in mature rats, and migrated from bottom to top of villus with epithelial cellular development. The positive expression of PCNA was similar with c-jun during the same time, but the distinction between them was location of their expression. The expression of c-jun in mature rat only lay in the top of villus, while the expression of PCNA was limited to intestinal crypts. The expression of p38 during stages of development and mature, mainly was in mitogenic cells. CONCLUSION: The results indicate that the strong expression of tumor gene c-jun at the early development and mature stages of intestinal epithelial cells at the special region is related to cellular differentiation, and p38 is probable correlate with cellular mitogenesis.

Animals↗
PubMed2003

[Passage adaptability of candidate strains for hemorrhagic fever with renal syndrome purified vaccine in Vero cells and their immunogenicity].

OBJECTIVE: To adapt the candidate strains of hemorrhagic fever with renal syndrome (HFRS) purified vaccine to Vero cells and to study their antigenicity and immunogenicity. METHODS: The viral strains H8207 (Hantaan virus, HTN) and Y86013 (Seoul virus, SEO) were continuously propagated in Vero cell by the terminal dilution method and studied the characteristics of virus multiplication, viral titers and the amounts of virus antigen after serial passages. Three batches of crude monovalent inactivated vaccine were developed using the different passages of these 2 viral strains. RESULTS: The strains H8207 and Y86013 adapted to Vero cells and stably grew on the cells with high titers. Rabbits immunized with the crude vaccines of H8207 and Y86013 showed 100% sero-conversion and the neutralizing antibody titers of the rabbit immune sera reached 1?10 at 4 weeks after 2 times of immunization. CONCLUSIONS: The results suggest that these 2 candidate strains had adapted to Vero cells, possessed high titers and good immunogenicity and be feasible to prepare the HFRS purified vaccine in Vero cells.

Animals↗
PubMed2003

[An epidemiological study on factors affecting serum thyroglobulin levels].

OBJECTIVE: To investigate the effects of several factors affecting serum thyroglobulin (TG) levels among people aged 14 or more. METHODS: We selected Panshan with median urinary iodine (MUI) 83.45 micro g/L as a deficient iodine intake community, Zhangwu with MUI 242.85 micro g/L as a sufficient iodine intake community and Huanghua with MUI 650.87 micro g/L as an excessive iodine intake community. Serum TG and thyroid stimulating hormone (TSH) were measured in 3,335 subjects whose thyroglobulin antibody (TGAb) were negative and thyroid volume were examined using B-ultrasound. RESULTS: In the population with MUI of 80 - 650 micro g/L, serum TG levels presented a "V" curve. An elevated serum TG was found in both the communities with deficient iodine intake and excessive iodine intake. The same trend was shown in the groups with different levels of serum TSH. An elevated serum TG was found in both the groups of TSH < 0.3 mU/L and TSH > 4.8 mU/L. The serum TG levels was positively correlated with thyroid volume and was higher in female subjects than in male. An increased serum TG was found in subjects of aged 50 in the community with deficient iodine intake. CONCLUSION: Serum TG level is affected by gender, amount of iodine intake, serum TSH level and thyroid volume.

Adolescent↗
PubMed2003

[Role of kaliuretic peptide and molar ratio of kaliuretic peptide/atrial natriuretic peptide in atrial fibrillation].

OBJECTIVE: To investigate the role of kaliuretic peptide (KP) and molar ratio of KP/ atrial natriuretic peptide (ANP) in atrial fibrillation. METHODS: The levels of plasma KP and ANP in 23 patients with paroxysmal atrial fibrillation (group I), 24 patients with persistent atrial fibrillation (>1 year, group II) and 20 healthy humans (group III) were determined with radioimmunoassay. RESULTS: Compared with group III, the levels of plasma KP and ANP of the group I and group II were both higher (both P<0.01). Compared with group III, the level of KP/ANP of the group I was lower (P<0.01), while that of group II was no substantial change (P>0.05). CONCLUSION: The change of levels in ANP, KP and ANP/KP may play important role in atrial fibrillation.

Atrial Fibrillation↗
PubMed2003

[Observation on the effects of urapidil on hemodynamics in heart dysfunction dogs by thoracic electrical bioimpedance].

OBJECTIVE: To observe the effects of urapidil on hemodynamics in heart dysfunction dogs by thoracic electrical bioimpedance. METHODS: Sixteen health anesthesia dogs were taken pentobarbital till their hearts dysfunction. Then 10 dogs were taken urapidil injection (4 microg x kg(-1) x min(-1)) and 6 dogs were taken the same doses of normal saline, and heart rate (HR), stroke volume (SV), cardiac output (CO), pre-ejection period (PEP), left ventricular ejection time (LVET), systole time ratio (STR), isovolumic relaxation time (IRT), pulmonary capillary wedge pressure (PCWP), left ventricular end-diastolic pressure (LVEDP), total peripheral resistance (TPR), stroke work (SW) and cardiac work (CW) were continuously monitored by non-invasive hemodynamic monitoring system. Data were recorded at 15 minutes, 30 minutes, 60 minutes, 90 minutes and 120 minutes after dysfunction. RESULTS: Compared to the group of normal saline, urapidil could increase CO and SV, shorten PEP and STR, decrease PCWP, LVEDP and TPR, increase SW and CW. CONCLUSION: The change of hemodynamics in heart dysfunction dogs can be observed, non-invasively and accurately, by thoracic electrical bioimpedance. Urapidil can obviously decrease preload and postload of heart, increase CO and myocardial contract potentiality, and improve heart function.

Adrenergic alpha-1 Receptor Antagonists↗
PubMed2003

[Expressive characteristics of epidermal growth factor and its receptor in tissues of fetal and adult intestines].

OBJECTIVE: To explore the expressive characteristics of epidermal growth factor (EGF) and its receptor (EGFR) in tissues of fetal and adult intestines. METHODS: The expression intensity and distribution of EGF and EGFR were detected with pathological and immunohistochemical methods in 6 specimens of adult (16-54 years) intestines and 18 specimens of fetal intestines with different gestational ages (13-31 weeks). RESULTS: Positive protein particles of EGF and EGFR could be detected in tissues of fetal and adult intestines. The protein expressions of EGF and EGFR were elevated progressively with the gestational age. EGF was mainly located in the cytoplasm and extracellular matrix of intestinal villus cells, endothelial cells and tunica serosa epithelial cells, while EGFR chiefly distributed in the cellular membrane of these cells. CONCLUSION: The endogenous EGF and EGFR might be involved in the intestinal development at embryonic stage, in the structural and functional maintenance at adult stage, and in the wound healing after injury.

Adolescent↗
PubMed2003

[Endovascular stent-graft exclusion on aortic dissection and dissecting aneurysm].

OBJECTIVE: To study the techniques and therapeutic effects of endovascular stent-graft exclusion in aortic dissection and dissecting aneurysm. METHODS: The clinical data of 20 cases with aortic dissection and(or) dissecting aneurysm were analysed. Stanford A dissection was found in 2 cases, in which one had a tear entry on ascending aorta. Stanford B dissection was found in 18 cases. Five patients had two or more tear entries in different sites. Endovascular polyester-covered stent-graft exclusion was performed in all cases, of which, one case was also given fenestration and graft replacement and one subjected to Y graft bypass from ascending aorta to the left common carotid artery and left subclavian artery before endovascular stent-graft exclusion. RESULTS: No one died in operation. One patient died of heart infarction on the third day after operation. During the followup of 1 - 20 months, 19 patients were alive well (95%). The aortic dissections and(or) dissecting aneurysms of all the patients disappeared without endoleaks and organ or limb ischemia. CONCLUSION: Endovascular stent-graft exclusion with high successful rate, low mortality and high survival rate, is simple, safe and effective in treating aortic dissection and dissecting aneurysm.

Adult↗
PubMed2003

[Characteristics of P38 mitogen-activated protein kinase and c-Jun expression in hypertrophic scar and their effects on scar formation].

OBJECTIVE: To observe the protein expression of phosphorylated form of P38 mitogen-activated protein kinase(P38MAPK) and c-Jun in hypertrophic scar skin and to explore their influences on the formation and maturation of hypertrophic scar. METHODS: The expression intensity and distribution of phosphorylated form of P38MAPK and c-Jun were examined with immunohistochemistry and pathological methods in 16 cases of hypertrophic scar skin and 8 cases of normal skin. RESULTS: In normal skin, the positive signals of phosphorylated form of P38MAPK mostly distributed in basal lamina cells of epidermis, while c-Jun was mainly located in epidermal cells and endothelial cells. The positive cellular rates of two proteins were 21.3% +/- 3.6% and 33.4% +/- 3.5% respectively. In proliferative hypertrophic scar skin, the particles of phosphorylated P38MAPK and c-Jun were mainly located in epidermal cells and some fibroblasts. The positive cellular rates of two proteins were significantly elevated to 69.5% +/- 3.3% and 59.6% +/- 4.3% respectively (P < 0.01). In mature hypertrophic scar, the expression of these proteins decreased but was still higher than that of normal skin. CONCLUSION: The formation and maturation of hypertrophic scar might be associated with the alteration of phosphorylated P38MAPK and c-Jun protein expression in hypertrophic scar.

Adolescent↗
PubMed2003

[Experimental study on recombinant human platelet-derived growth factor gel in a diabetic rat model of cutaneous incisal wound healing].

OBJECTIVE: To investigate the effect of recombinant human platelet-derived growth factor (rhPDGF-BB) on cutaneous incisal wound healing in diabetic rats and this factor does-effect relationship. METHODS: Thirty Wistar diabetic rats were used in this study. Four full-thickness skin wounds of 2.54 cm(2) were incised in the back of each rat. The wounds were divided into five groups: three groups were treated with different dosage of rhPDGF-BB gel (14.0 microg/cm(2) wound, 7.0 microg/cm(2) wound, 3.5 microg/cm(2) wound), other two groups were treated with vehicle or untreated, respectively. rhPDGF-BB gel was topically applied to the wounds from 1 to 14 days. The wound healing effect was assessed by the measurements of the wound area, subcutaneous chamber and histological changes of each group. RESULTS: On 14 days, the wounds of the three groups treated with rhPDGF-BB contracted to (0.22+/-0.30)cm(2), (0.05+/-0.06)cm(2), (0.32+/-0.32)cm(2), respectively. The area of the middle dosage groups was significantly smaller than those treated with vehicle 0.23+/-0.22 cm(2) (P<0.05) and untreated (0.22+/-0.25) cm(2) (P<0.05). On 7 days, the subcutaneous chambers of the three treated groups contracted to (0.04+/-0.03)ml, (0.02+/-0.02)ml, (0.06+/-0.03)ml, and there was a statistic significance when comparing middle dosage group with vehicle group (0.06+/-0.03) ml (P<0.05) and untreated group (0.07+/-0.05 ml (P<0.05). As for histological examination, much more granulation formation was shown in the wound bed in middle dosage group than that in other four groups on 7 days, and some of the wounds treated with middle dosage were healing on 14 days. CONCLUSION: It suggested that topical application of rhPDGF-BB might improve wound healing in diabetic rats. The effective dosage of rhPDGF-BB is 7.0 microg/cm(2) wound.

Animals↗
PubMed2003

[Characteristics of epidermal growth factor and its receptor expression in dermal chronic ulcers].

OBJECTIVE: To investigate the expression and location of epidermal growth factor (EGF) and its receptor (EGFR) in dermal chronic ulcers and normal skin in order to explore their influence on ulcer formation. METHODS: The expression intensity and distribution of EGF and EGFR were detected with pathological method and immunohistochemistry method in 8 cases of dermal ulcers, 8 cases of edge of ulcer and 8 cases of normal skin. RESULTS: The Positive signals of EGF could be found in epidermal cells, endothelial cells and some fibroblasts; EGFR was principally located in the cytoplasm and cellular membrane of these cells mentioned above in normal skin. From normal skin, edge of ulcer to ulcerative tissues, the protein contents of EGF and EGFR were decreased progressively. In ulcerative tissues, EGF was mostly distributed in monocytes and macrophages while EGFR was chiefly sited in monocytes. When compared with normal skins, the protein expression of EGF and EGFR was notably reduced in ulcerative tissues (both P<0.01). The positive cellular ratios of two proteins were reduced to (7.1+/-5.2) % and (8.8+/-5.5) % of those in normal skin respectively (all P<0.01). CONCLUSION: The formation of dermal chronic ulcers is closely associated with the reduction of EGF and EGFR protein expression which may lead to binding obstruction between EGF and its receptor.

Adult↗
PubMed2003

[Effects of serum from normal and burned rats on the biological behavior of bone marrow stromal cells].

OBJECTIVE: To investigate the effect of serum from normal and burned rats on the biological behaviors of bone marrow stromal cells (BMSCs). METHODS: Bone marrow was extracted from sacrificed Wistar rats and BMSCs were then incubated in F-12 medium in the presence of fetal calf serum (FCS, group F), normal rat serum (group N), serum harvested from burned rats at 3 days (group B1) and 14 days (group B2) after burn injury. The growth curve, cell cycle, apoptosis rate and contents of DNA of BMSCs were investigated. RESULTS: The growth curves of cells incubated in different rat serum were similar, but were significantly different from that of cells incubated in FCS. The doubling time of cells incubated in rat serum from group N, B1 and B2 were 23.7, 18.6 and 20.2 hours, respectively, which were significantly shortened compared with that in group F. Compared with group F, the numbers of cells at platform phase in group N, B1 and B2 were greater. The ratios of cells at phase G0/G1 in group B1 and B2 were significantly lower than those in other groups (all P<0.01), but the ratios of cells at phase S were adverse (P<0.01). Contents of DNA in cells incubated in rat serum were greater than that in cells incubated in FCS (P<0.05 or P<0.01). Contents of DNA in cells incubated in serum from burned rats were greater than that in cells in normal rat serum (P<0.01). The rate of cell apoptosis in group B1 was higher than those in other groups (P<0.01). CONCLUSION: Rat serum is more effective to stimulate proliferation of BMSCs from rat in vitro than FCS. There are probably many factors affecting the growth of BMSCs, the contents of which changed with the time after burn injury. The effects of serum from burned rats on the growth of BMSCs are complex.

Animals↗
PubMed2003

[Separation of carbon dioxide from gas mixture by membrane contactor].

In this paper, membrane contactor made of hydrophobic hollow fiber polypropylene porous membrane (HFPPM) was used for separating carbon dioxide (CO2) from CO2/N2 mixtures. The effects of absorbents, concentration and flow rate of feeding gas and absorbent solution, lumen/shell side processes and gas permeability of HFPPM(P) on the CO2 absorption efficiency were investigated. It was found that the absorption efficiency of three absorbents ranged in order of ethanolamine > sodium hydroxide > diethanol amine. For CO2/N2 mixture of c(in) = 20% and v(in) = 0.5-1.0 m3.h-1, and MEA solution of cMEA = 2.5 mol.L-1 and vL = 40-160 L.h-1, the removal efficiencies of CO2 (eta) and the mass transport coefficients (K) was 9.5% - 99.5% and 4.5-6.8 x 10(-4) m.s.-1 respectively. K of the modules made of HFPPM with larger P was relatively larger. eta in lumen process was 30% larger than that in shell process.

Absorption↗
PubMed2003

[Establishment and characterization of a new squamous cell carcinoma cell line CS1213 from the human uterine cervix].

OBJECTIVE: To establish a human cervical carcinoma cell line. METHODS: A primary culture was initiated from malignant tissue collected by dissection of cervical biopsy specimens. Characterizing cells in culture which included morphological observation, biological and karyotypic analysis, experimental tumorigenesis and the expression of p53, bcl-2 and Ki67 genes was carried out. RESULTS: The new established cervical carcinoma cell line (CS1213) had been maintained in culture for over 170 generations. The cells which were nonadherent had a common, rounded appearance with a cell cycle time of 25-hour and a 19 colony formation rate in soft agar. Electron micrographs demonstrated abundant tonofilaments in the cytoplasm. The karyotype showed a hyperdiploid feature with a main chromosome stem number ranged from 80 to 88. The culture was not contaminated by mycoplasma and had a distinct lactic acid dehydrogenase isozyme pattern. High expression level of p53 (31.9%), bcl-2 (89.3%) and Ki67 (33.7%) proteins was detected by flow cytometry. The xenogeneic tumors were grown in nude mice with the histological structure of the original one. CONCLUSIONS: The novel CS1213 cells have the characteristics of human cervical squamous cells and could be used as an appropriate cellular model system for studying tumor invasion and metastasis.

Animals↗