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X Jiang

Publications and source records attributed to X Jiang.

At least 181 records · Page 10Linked to original sources
PubMed2000

[Construction, expression and activity test of a reshaping single-chain antibody against human CD3].

Monoclonal antibody (McAb) against human CD3 can adjust human body's immune statement in various ways, so that its clinical potential is highly regarded. In order to overcome the immunogenecity related to the murine McAb, this research effort was focused on constructing a reshaping single-chain antibody(scFv) against human CD3 employing antibody engineering. First, the CDRs of the murine McAb against human CD3 OKT3 was transplanted into the light-chain framework regions (FRs) of human McAb LS1 and the heavy-chain FRs of human McAb Nd respectively, spatial conformation was predicted by computer analysis. Then some particular residues were replaced in FRs basing on the result of conformational prediction to draw out the amino acid sequences of the reshaped VL and VH. The genes were chemically synthesize and inserted into an expression vector pROH80 to construct the reshaping scFv. Inducing the expression of reshaping scFv, the products are mainly as inclusion bodies. The reshaping scFv was expressed in another vector pALM. The inclusion bodies were denatured and then renatured by gel filtration. The renatured products were purified by immobilized metal affinity chromatograph (IMAC). Finally, the antigen-binding activily of the reshaping scFv against human CD3 was testified by the Compelitire in hibilory fluorescenceactivated cell sorting (FACS). The competitive inhibition rate is 18%.

Amino Acid Sequence↗
PubMed2000

Pulmonary function changes following surgical correction for pectus excavatum.

OBJECTIVE: To assess whether and to what extent pulmonary function returns to normal after surgical correction for pectus excavatum. METHODS: Twenty-seven patients who could be examined in person at the outpatient department of our hospital were included in this study. Of these patients, 24 were boys and 3 were girls, with age ranging from 3 to 16 years (mean: 8.67 years). The mean age at surgery was 4 years and mean years at follow-up was 6.8. Pulmonary function measurements included inspiratory vital capacity (IVC), total lung capacity (TLC), residual volume (RV), functional residual capacity (FRC), RV/TLC ratio, maximal voluntary ventilation (MVV), forced ventilatory capacity (FVC), forced expiratory volume in one second (FEV1), maximal mid-expiratory flow (MMEF), maximal expiratory flow at 75% vital capacity (V75), maximal expiratory flow at 50% vital capacity (V50), maximal expiratory flow at 25% vital capacity (V25) and breathing reserve ratio (BR). RESULTS: TLC, FRC, MVV, MMEF, V75 and V50 were not different from normal values. IVC, FVC, FEV1 and V25 were significantly decreased compared with normal values. RV and RV/TLC were high in 87.5% cases. CONCLUSIONS: Preoperative symptoms improved substantially after operation. Little airway obstruction was observed postoperatively, suggesting that patients with pectus excavatum should have surgery as early in life as possible, preferably by age 3.

Adolescent↗
PubMed2000

[Inhibitory effects of ligustrazine on the expression of intercellular cell adhesion molecule-1, vascular cell adhesion molecule-1 in human umbilical vein endothelial cells induced by preeclamptic plasma].

OBJECTIVE: To determine whether plasma from preeclamptic women induces expression of intercellular cell adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) on cultured endothelial cells, and the effects of ligustrazine (LTZ) on the expression of ICAM-1, VCAM-1. METHODS: Human umbilical vein endothelial cells (HUVEC) were isolated by collagenase mixed with trypsin. LTZ was added to HUVEC monolayers grown to confluency on 96-well microplates for 30 minutes. Then HUVEC were incubated with medium containing 20% plasma (volume/volume) either from women with preeclampsia or normotensive pregnancy or nonpregnant women. ICAM-1, VCAM-1 expression was determined after 16 hours of exposure by an enzyme-linked immunosorbent assay (ELISA) technique performed on the cell monolayer. RESULTS: There was a statistically significant increase in ICAM-1, VCAM-1 expression in the endothelial cells exposed to preeclamptic and nonpregnant plasma compared with those exposed to normotensive plasma. Pretreatment with LTZ could reduce the expression of ICAM-1 exposed to preeclamptic plasma, and reduce the expression of VCAM-1 exposed to any of the three sources of plasma. CONCLUSIONS: Preeclamptic plasma induces ICAM-1 and VCAM-1 expression in HUVEC in vitro. Ligustrazine may inhibit the upregulation effects of ICAM-1 and VCAM-1 expression induced by preeclamptic plasma.

Adult↗
PubMed2000

Effect of prenatal tetrandrine therapy on pulmonary vascular structural remodeling in the nitrofen-induced CDH rat model.

OBJECTIVE: To examine the effects of prenatal tetrandrine (Tet) therapy on pulmonary arterial structural remodeling in nitrofen-induced congenital diaphragmatic hernia (CDH). METHODS: CDH was induced in fetal rats by maternal administration of 100 mg nitrofen by gavage on day 9.5 of gestation (term, day 22). Control animals received olive oil (OO). Tet (24 mg/kg per day) or normal saline (NS) was given by gavage every day from 16 to 20 days of gestation, and fetuses were delivered by caesarean section on day 21.5. Lung sections from 3 fetuses in each group were studied. The number of vessels were calculated, the external diameter (ED), medial wall thickness (MT), percent of medial wall thickness, and wall structure were evaluated by image analysis software. RESULTS: In the pre-acinar arteries, CDH-NS pups had a significantly increased %MT compared with the OO-NS group (P < 0.05), while CDH-Tet animals had a reduced %MT compared with the CDH-NS rats (P < 0.05). Similar results were seen in the intra-acinar level. Significant differences were observed between CDH-NS animals and OO-NS controls in the percentage of muscularized intra-acinar blood vessels (P < 0.001). Tet-treated CDH pups had a reduced percentage of muscularized intra-acinar arteries compared with CDH-NS animals. CONCLUSIONS: Medial hypertrophy is present in both the pre-acinar and intra-acinar arteries in the nitrofen-induced CDH rat model. Tet treatment inhibits medial hypertrophy and reduces the percentage of muscularized intra-acinar vessels. Prenatal Tet therapy may be efficacious in reducing the risk of PH in human newborns with CDH.

Alkaloids↗
PubMed2000

Modified sternal elevation for children with pectus excavatum.

OBJECTIVE: To describe our experience in the treatment of pectus excavatum (PE) using a modified sternal elevation procedure. METHODS: From Oct. 1986 to Dec. 1997, 171 patients with PE were admitted to the Department of Pediatric Surgery of the First Hospital of West China University of Medical Sciences. All patients were diagnosed through a history and physical examination. Cardiopulmonary function was assessed by M-mode echocardiography and instrument of pulmonary function in 40 patients before and 4.2 years after surgery which was performed between 1989 and 1994. We performed the following three procedures in the sternal elevation: (1) forming the metal strut in a "arch" shape, (2) suturing the perichondrium into a "pipe" shape, and (3) encouraging patients to do chest expansion exercise after operation. All patients were followed up for 1 to 12 years. RESULTS: The normal contour of the costal cage was enlarged in all but one patient. Exercise tolerance was improved, and cardiac function recovered to the same level as in healthy children, while pulmonary function recovered very slowly after surgery. CONCLUSION: The normal appearance of chest wall can be recovered and normal cardiopulmonary function can be restored by the modified sternal elevation procedure in children with PE.

Adolescent↗
PubMed2000

The cellular and molecular mechanism of laminin-glycopeptides on anti-metastasis.

OBJECTIVE: To further study the anti-metastasis mechanism of laminin-glycopeptides on carcinoma cell proliferation, apoptosis and the secretion of matrix metalloproteinases. METHODS: Human hepatocellular carcinoma cells in serum free medium were incubated on laminin-coated substrate with or without laminin-glycopeptides at a final concentration of 50 micrograms/ml. The total number of surviving cells after incubating for the indicated time was assayed by MTT assay. DNA synthesis of the incubated cells was detected by 3H-TdR incorporation. Cell cycle was analysed by FACS. The mitotic index of Giemsa stained cells was assessed. Cell apoptosis was detected by both FACS and an acridine orange staining method. Matrix metalloproteinase secretion was analysed by gelatin zymography. RESULTS: The total number of surviving cells incubated on laminin in the absence of laminin-glycopeptides was significantly larger than that in the presence of laminin-glycopeptides. Laminin promoted 3H-TdR incorporation of carcinoma cells, decreased the percentage of cells in G1 phase and increased the percentage of cells in S phase. In contrast, laminin-glycopeptides could inhibit the effect of laminin as shown by 3H-TdR incorporation and cell cycle analysis. The percentage of cells in G2 + M phase and the mitotic index among various groups showed no significant difference. Matrix metalloproteinases secretion from cells treated by laminin-glycopeptides was much less compared to that without the treatment by laminin-glycopeptides. CONCLUSION: Laminin may stimulate cell proliferation, while laminin-glycopeptides could significantly inhibit the effect of laminin by inhibiting DNA synthesis and arresting the carcinoma cell cycle from G1 to S phase. These effects may inhibit not only tumor growth of the primary carcinoma, but also the establishment of metastases at ectopic tissues. Laminin-glycopeptides could also inhibit the secretion of matrix metalloproteinases from carcinoma cells and this may contribute to their decreased invasive and metastatic phenotype. This study further revealed the cellular and molecular mechanism of laminin-glycopeptides on anti-metastasis.

Apoptosis↗
PubMed2000

[Clinical and experimental study on effect of rhubarb on gastrointestinal blood flow perfusion].

OBJECTIVE: To study the effect of rhubarb on gastrointestinal (GI) perfusion in critical illness and hemorrhagic shocked rats. METHODS: Clinical study: Sixty-four septic patients suffered from stress ulcer were treated with rhubarb at a dose of 25 mg/kg, 25 non-septic patients were taken as control. The GI perfusion was evaluated by intramural pH. Animal study: SD rats were anesthetized with intraperitoneal sodium pentobarbital at a dose of 20 mg/kg. Then the animals were blood-letting, the blood pressure reduced to 5.32 kPa and maintained for 120 minutes. They were resuscitated at the end of shock by reperfusing all the shed blood. The rats were divided into four groups: normal control, shock group, treated group (shocked rats were treated with 50 mg/kg rhubarb by the end of shock), and rhubarb group (normal rats were treated with rhubarb). Laser Doppler determination was applied to estimate the GI perfusion. RESULTS: Clinical study: The pH in septic patients was much lower than that in the control, whereas rhubarb could obviously elevate GI pH (P < 0.01). In addition, rhubarb also had a good effect on gastric hemorrhage caused by stress ulcer, the effectiveness was 73.4%. Animal study: Although the shocked rats were resuscitated completely, their GI perfusion was much lower than that in the control. Rhubarb could significantly improve the mucous membrane of GI and mesenterium perfusion (P < 0.01). Furthermore, rhubarb also increased the GI perfusion in normal rats. CONCLUSION: The rhubarb could improve the GI blood perfusion in critical illness and shocked rats.

Adolescent↗
PubMed2000

[Operative treatment of displaced proximal humeral fractures: follow-up and analysis of 31 patients'].

OBJECTIVE: To study the methods and the results of operative treatment of displaced proximal humeral fractures. METHODS: We reviewed thirty-one patients who had been diagnosed as having displaced proximal humeral fractures and had been operated on from July 1989 to December. 1998 in our hospital. The mean follow-up time was 40.5 months (8 - 124 months). Their age ranged from 15 to 62 years (average, 36.8 years); 18 patients were male and 13 female. Neer fracture classification system and rating system were used. In all patients, delto-pectoral approach was adopted. Twelve fractures were fixed with plates, fifteen fractures with screws, and four fractures with Kirschner wire and plaster. RESULTS: Of two-part surgical neck fractures, nine of thirteen patients (69%) were excellent or good with no necrosis and un-union. In three-part or four-part fractures, the rate of satisfaction with open reduction and internal fixation (ORIF) was rather lower. In three-part fractures, the rate of humeral head necrosis was 44%, and in four-part fractures, over 75%. CONCLUSIONS: In two-part and three-part fractures, ORIF is a better treatment, but care should be taken to avoid using plates. As for classic four-part fractures, the rate of satisfaction with ORIF is poor and the rate of necrosis is higher.

Adult↗
PubMed2000

[Does simple posterior dislocation of the elbow necessitate strict immobilization?].

OBJECTIVE: To research for the ideal treatment of isolated posterior dislocation with the elbow after reduction. METHODS: 36 patients of isolated posterior dislocation of the elbow after closed reduction (male 26, female 10; left 14, right 22; dominant extremity 21, undominant extremity 15; average age 22) were examined by varus and valgus stress test and push-draw test. Satisfactory stability from 30 degrees to 130 degrees flexion of the elbow was found in all patients. For the 30 patients below 35 years old, long-arm posterior splint was applied to immobilize the elbow joint at 90 degrees flexion and pronation for one week. For 6 patients over 35 years old, we only immobilized the elbow joint for 3 to 5 days with a neck-wrist sling. Prompt active motion begin after the swelling and pain reduced slightly, but the last 30 extension was not allowed for the first 1 to 2 weeks. Forceful passive motion and stretching of the elbow joint were avoided in all patients. RESULTS: The average follow-up time was 9 months (3 - 15 months). Range of motion and muscle power were regained within 3 - 4 months. 32 patients rehabilitated completely and 4 of the 6 patients decreased extension for 5 degrees - 10 degrees. No unstable symptoms and signs or recurrent dislocation were found. No ectopic calcification or post-traumatic arthritic changes were found on X-ray follow-up. CONCLUSIONS: The ulna-humeral joint is one of the most highly constrained joints in the body with intrinsic stability. Bony structure is stable enough to allow for capsular and ligamental structure healing, even during active motion. For isolated posterior dislocation of the elbow joint, short-term immobilization and early functional exercise are desirable. Elbow instability and recurrent dislocation are rare and do not necessitate long-term strict immobilization.

Adolescent↗
PubMed2000

[Measurement of tumor angiogenesis in primary lung cancer].

OBJECTIVE: To study tumor angiogenesis in primary lung cancer and its relation with lymph node metastasis, tumor cell apoptosis, and cell proliferation. METHODS: Intratumor microvessel was detected by factor VIII polyclonal antibody using immunohistochemistry. Tumor cell apoptosis was detected by TUNEL method. Cell proliferation was analyzed by flow cytometry. RESULTS: Intratumor microvessel density (MD) was significantly lower in stage I lung cancer than in stage II and stage III (P < 0.01). MD was significantly higher in the tumors with lymph node metastasis (P < 0.01). With the increase in MD, there would be a 1.2-fold increase in the risk of lymph node metastasis (P < 0.01). With the increase of MD, apoptosis index (AI) of the tumor significantly decreased, but no relationship between MD and cell proliferation index (PI) was observed. CONCLUSION: Tumor angiogenesis promotes growth and metastasis of lung cancer. Tumor angiogenesis also can inhibit the apoptosis of lung cancer.

Adult↗
PubMed2000

[A molecular epidemiological investigation on Leptospira interrogans serovar hebdomadis and australia in China].

OBJECTIVE: In order to confirm whether cattle serve the source of infection for patients with Leptospira interrogans serovar hebdomadis and australia. METHODS: 12 field strains of leptospira interrogans serovar hebdomadis and australia were isolated from blood samples of patients with leptospirosis and farm cattle urine. An analysis of chromosome DNA restriction endonuclease patterns (REP) and restriction fragments length polymorphism (RFLP) of 16S + 23S rRNA gene were processed by digestion of chromosome DNA using EcoR I. RESULTS: The same serovar field strains of Leptospira interrogans from blood samples of patients with leptospirosis and farm cattle urine resulted in unique restriction endonuclease patterns (REP) and ribosomal types (RT). The chromosome DNAs from field strains that belonged to different serovars of Leptospira interrogans caused different restriction endonuclease patterns and ribosomal types. CONCLUSION: In accordance with this results, we recognize that farm cattle serve the infectious source of leptospirosis serovar hebdomadis and australia thus may have realistic significance in the control of leptospirosis serovar epidemic of hebdomadis and australia in China.

Animals↗
PubMed2000

[A preliminary study on body level of nitric oxide in workers exposed to carbon disulfide].

OBJECTIVE: To study changes in body plasma level of nitric oxide (NO) in workers exposed to carbon disulfide (CS(2)) and its possible mechanism. METHODS: Plasma levels of NO and lipid peroxide (LPO) and activity of erythrocyte superoxide dismutase (Ery-SOD) were determined in the workers exposed and unexposed to CS(2) in a chemical synthetic fiber works. RESULTS: Level of NO was (43.28 +/- 19.83) and (50.07 +/- 21.01) micromol/L in high- and low-dose exposed groups, respectively, significantly lower than that in the control group, which was (70.66 +/- 26.83) micromol/L (P < 0.05). Activity of Ery-SOD was 4 832.21 u/g Hb and 3,520.80 u/g Hb in high- and low-dose exposed groups, respectively, significantly higher than that in the control group, which was 2,425.34 u/g Hb (P < 0.05). Level of LPO was 19.38 and 17.09 micromol/L in high- and low-dose exposed groups, respectively, significantly higher than that in the control group, which was 4.37 micromol/L (P < 0.05). CONCLUSION: Occupational long-term exposure to CS(2) could induce reduction of NO level in the body with its mechanism related to increase of super-oxygen cation O(2)(*-) induced by CS(2).

Adolescent↗
PubMed2000

[Establishment and application of a computerized radiography cephalometrics system].

We have developed a new-typed computerized radiography cephalometrics and prediction system. It includes cephalometrics, growth prediction, orthopedics/orthodontics prediction and profile prediction. In this study, 47 lateral cephalograms were randomly selected to process a reliability test. The results showed the two groups were in agreement on all of the 25 measurement index. The system is easier, quicker and less prone to error than traditional cephalometrics approach. It is convenient for orthodontists.

Cephalometry↗
PubMed2000

[Transposition of expanded cervical-shoulder skin flaps for the repair of cicatricial contracture deformity of neck].

OBJECTIVE: To evaluate the efficacy of expanded cervical-shoulder skin flap in the treatment of cicatricial contracture deformity of neck, and improve the method for the repair of soft tissue defect of neck. METHOD: 12 patients with cicatricial contracture of neck were treated by pre-expanded cervical-shoulder skin flap and then transposition for the reconstruction of the defect after cervical scar resection. RESULT: All the 24 flaps were survived. Postoperative follow-up for 6 months to one year showed that the cervico-mandibular function and the external appearance of the flaps were satisfactory without swelling and contracture. CONCLUSION: Pre-expanded cervical-shoulder skin flap is available for the treatment of cicatricial contracture deformity of neck.

Adolescent↗
PubMed2000

[Relationship between tissue inhibitors of metalloproteinase and metastasis and prognosis in breast cancer].

OBJECTIVE: To investigate the clinical significance of tissue inhibitors of metalloproteinase (TIMP) -3 and TIMP-4 in human breast cancer. METHODS: The levels of TIMP-3 and TIMP-4 mRNA in paraffin-embedded breast carcinoma specimens from 70 patients with primary invasive breast cancer who had undergone radical mastectomy from January of 1984 to December of 1985 were assessed by in situ hybridization assay. Intratumoral microvessel density (MVD) and vascular endothelial growth factor (VEGF) expression were detected by the standard streptavidin biotin peroxides method. RESULTS: Both TIMP-3 and TIMP-4 mRNA expressions were higher in patients with axillary lymph node metastasis than in those without metastasis (P < 0.01), and patients with higher expression of any of these two genes had a better prognosis than those with lower expression (P < 0.01). We introduced lymph node status, TNM staging, MVD and VEGF expression, plus TIMP-3 and TIMP-4 to the Cox's proportional hazards regression model for significant analysis, and found that the TIMP-3, TNM staging and MVD play an important role in prognosis of this group. CONCLUSIONS: TIMP-3 and TIMP-4 are correlated with metastasis in breast cancer, and TIMP-3 demonstrates an independent prognostic factor for the patients. These results provide a valuable clue for developing new, practical prognosticators in breast cancer patients.

Breast Neoplasms↗
PubMed2000

[Inspection of writing-time and script by FTIR microscope].

The IR spectra of different ball-pen script at different paper were determined by FTIR microscope and ATR objective. The spectra of different script on different paper in no time and in three-month time are compared. The result is showed that the most of IR spectra of different ball-pen are different and the IR spectra got in no time and in three-month time are different. The FTIR spectra can be used for inspecting scripts and help to inspect the writing-time.

Forensic Medicine↗
PubMed2000

[Study on the determination of contents of Zn, Cu and Co by using artifical neural network and ultraviolet spectrum].

By means of artificial neural network and back-propagation train algorithm, the three-component metal coordinate compounds of PAR-Zn, Cu, Co were determined simultaneously, in which the spectra overlapped. In 580-440 nm, the absorbance(A) at 14 wavelength were taken as character parameter of artificial neural network, and samples were arranged by method of uniformity design. The mean recovery of Zn, Cu, Co were 95.22%, 95.98% and 100.5%. The experiment results show that the determination is accurate, and the method has good performance.

Cobalt↗