Biomedical subjects

Zhi-gang Yang

Publications and source records attributed to Zhi-gang Yang.

5 recordsLinked to original sources

PubMed2005

[Development of a method for isolation, culture and proliferation of mouse NK cells].

AIM: To establish a method to isolate, purify, and culture mouse nature killer (NK)-cells in vitro. METHODS: NK-cells were isolated from splenic mononuclear cells (MNC) by a two-step adherence system and magnetic microbeads actived cell sorting (MACS), then these cells were cultivated with feeder cells and IL-2 in RPMI 1640 medium for 5, 10, 15, and 20 days. The enriched cells were counted and stained with anti-mouse CD3-FITC and anti-mouse NK1.1-PE. The purity of the NK-cells was determined by flow cytometry and the cytotoxicity to YAC-1 targets was detected by MTT assay. RESULTS: In the two-step adherence system, the enriched cells cultivated for 5, 10, 15, and 20 days were 0.5 x 10(7), 1.4 x 10(7), 2.6 x 10(7), and 3.0 x 10(7) respectively, and the percent of CD3(-) NK1.1(+) cells was 18.36%, 43.44%, 55.68%, and 60.03% respectively. The cytotoxicity to YAC-1 targets was significantly higher than that of splenic MNC(P<0.01), and increased from 41.93% up to 54.38%, 66.54%, 79.38%, and 83.86% respectively at 25:1 of effector:target ratio. After NK-cells were purified by MACS, the purity reached 93.60%ls, the enriched cells was 1.5 x 10(6), but proliferated to only 1.9 x 10(6) 20 days later. CONCLUSION: NK-cells isolated by using the two step adherence system proliferate abundantly, and the purity reaches 55%-60%. The cytotoxicity to YAC-1 targets is about 80% at 25:1 of effector:target ratio.

Animals↗

PubMed2004

[Idiopathic pulmonary fibrosis: correlation between helical CT findings and pulmonary function test results].

OBJECTIVE: To determine the correlation between helical CT findings and pulmonary function test (PFT) results from patients with idiopathic pulmonary fibrosis(IPF). METHODS: Helical CT scan was performed in 32 cases with clinically and/or pathologically proved idiopathic pulmonary fibrosis. Pulmonary function test for each patient was performed within 5 days before or after CT scan. The correlation between CT findings and pulmonary function test results was assessed. RESULTS: Pulmonary function test revealed characteristic restrictive ventilatory defect with reduction of total lung capacity, residual volume, vital capacity, and diffusing capacity of the lung for carbon monoxide. The patients with different severities of pulmonary function impairment had different CT features. 4 of 5 cases with slight impairment of the pulmonary function had the ground-glass opacity, 11 cases with moderate impairment showed the thickened interlobular septa (11/11, 100%), thickened lobular interstitium (9/11, 82%), distorted lobular structures (11/11, 100%) and thickened bronchovascular bundles (10/11, 91%). 16 cases with marked impairment showed the honeycombing (16/16, 100%) and the traction bronchiectasis (9/16, 55%). CONCLUSION: CT can provide significant information for the assessment of the pathologic severity of idiopathic pulmonary fibrosis. There is good correlation between CT findings and pulmonary function test results. CT combined with pulmonary function test can predict the progression, long term survival and response to therapy.

Adult↗

PubMed2004

[Optimal scanning collimation for segmental bronchi: experimental study with low-dose helical CT].

OBJECTIVE: To evaluate the effects of low-dose helical CT with different scanning collimation on the visualization of segmental bronchi and to determine the optimal scanning collimation in CT screening for early central lung cancer. METHODS: Forty healthy volunteers were randomly assigned to undergo the low-dose helical CT at 120 kVp, 50 mA, 0.75 s and pitch 1. One group (n = 20) underwent the sequential subsection scan of chest with the collimation of 10 mm for the apical and basilar zone, and of 8 mm and 5 mm for the hilar zone. The other (n = 20) went through CT scan with 10 mm collimation of the whole lung. The visualizations of lobar, segmental bronchi were compared at different collimations. ANOVA and multiple comparison were performed. RESULTS: The visualization of segmental bronchi on low-dose scan at 10 mm collimation was 60%, being lower than that at 8 mm (88%) or 5 mm (91%) collimation (P < 0.01). The segmental bronchi of right upper lobe were easily identified at collimation of 10 mm (82%), 8 mm (96%) and 5 mm (98%), as well as those of left upper lobe at 10 mm (83%), 8 mm (95%) and 5 mm (97%), whereas those of lingular lobe were difficultly identified at 10 mm (30%), 8 mm (60%) and 5 mm (70%). CONCLUSION: The lobar and segmental bronchi were visualized reliably by CT with 50 mA and 8 mm collimation, and therefore the sequential subsection scan of chest divided into three zones can be adapted to CT screening for early lung cancer.

Adult↗

PubMed2004

[Hydrogen peroxide upregulates interleukin-1beta-induced cyclooxygenase-2 expression in human pulmonary epithelial cells].

OBJECTIVE: To investigate the effect of hydrogen peroxide (H(2)O(2)) on interleukin-1beta (IL-1beta)-induced cyclooxygenase-2 (COX-2) expression in human pulmonary epithelial cells (HPEC). METHODS: HPEC were stimulated by IL-1beta or H(2)O(2) or both of them, COX-2 mRNA expression was determined by reverse transcription-polymerase chain reaction (RT-PCR), and prostaglandin E(2) (PGE(2)) release was detected by enzyme-linked immunosorbent assay (ELISA). Cells that were not stimulated by any reagent were used as controls. RESULTS: (1) The relative amount of COX-2 mRNA expression induced by 1, 5 and 10 mg/L of IL-1beta [(143.1 +/- 7.2)%, (179.9 +/- 9.0)%, (190.0 +/- 9.5)%, respectively] was significantly higher than that in the control group (32.9 +/- 1.7)% (P < 0.05, respectively). (2) The concentration of PGE(2) released by HPEC treated with 5 and 10 mg/L of IL-1beta [(20.86 +/- 5.23) x 10(-6) g/L, (31.16 +/- 2.64) x 10(-6) g/L, respectively] was significantly higher than that in the control group (10.49 +/- 0.36) x 10(-6) g/L (P < 0.05, respectively). (3) The relative amount of COX-2 mRNA expression induced by 0.10, 0.25 and 0.50 mmol/L of H(2)O(2) in the presence of IL-1beta [(149.2 +/- 7.5)%, (189.6 +/- 9.5)%, (239.1 +/- 12.0)%, respectively] was significantly higher than that in the cells treated with IL-1beta alone (66.1 +/- 3.7)% or that in the control group (41.6 +/- 2.1)% (P < 0.05, respectively). (4) The concentration of PGE(2) released by HPEC treated with 0.10, 0.25 and 0.50 mmol/L of H(2)O(2) in the presence of IL-1beta [(27.01 +/- 5.16) x 10(-6) g/L, (32.79 +/- 3.01) x 10(-6) g/L, (41.13 +/- 3.41) x 10(-6) g/L, respectively] was significantly higher than that in the control group (10.49 +/- 0.36) x 10(-6) g/L (P < 0.05, respectively). The concentration of PGE(2) released by cells treated with 0.25 or 0.50 mmol/L of H(2)O(2) in the presence of IL-1beta was significantly higher than that in the cells treated with IL-1beta alone (20.86 +/- 5.23) x 10(-6) g/L (P < 0.05, respectively). CONCLUSION: Hydrogen peroxide upregulates IL-1beta-induced COX-2 expression in HPEC at transcriptional level.

Cell Line↗

PubMed2004

[Effect of natural killer cell on hematopoiesis and immunity recovery in mouse allogeneic bone marrow transplantation].

OBJECTIVE: To study the effect of natural killer (NK)-cell on reconstitution of hematopoiesis and immunity in mouse allogeneic bone marrow transplantation (allo-BMT). METHODS: Lethally irradiated BALB/c (H-2(d)) mice were transplanted with C57BL/6 (H-2(b)) bone marrow plus peripheral T cells and/or NK cells. Recipients CD34(+) cells and H-2K(b+), CD3(+) and CD19(+) cells were detected by flow cytometry, peripheral white blood cell (WBC) by auto-cytometry, and the survival rates, engraftment, hematopoietic and immune recovery were observed. RESULTS: In the transplantation with NK cell infusion group, the survival rates, the WBC and CD34(+) cell counts, and the H-2(b+) and CD19(+) cells were significantly higher than that in without NK cell infusion group (P < 0.01). Twenty-eight days after transplantation, the CD3(+) cells in the NK cell infusion group [(33.69 +/- 3.36)%] were lower than that in without [(50.4 +/- 5.06)%] (P < 0.01), and there was no longer difference between these groups 60 days after transplantation (P > 0.05). CONCLUSION: In mouse allo-BMT, alloreactive NK cell enhances engraftment, promotes reconstitution of hematopoiesis and immunity and increases survival rates.

Animals↗