【 Abstract 】 Objective Overexpressions of epidermal growth factor (EGF) and EGF receptor have been associated with progression and invasive phenotype of pancreatic cancer. However, the underlying molecular mechanism by which EGF worked in pancreatic cancer cells has not been completely understood. In this study, effect of EGF on the invasion and metastasis of pancreatic cancer cells and its regulatory mechanism were investigated. Methods The effects of EGF on the proliferation, adhesion and invasion of pancreatic cancer cells were detected by WST-1 proliferation assay, adhesion assay and invasive assay, respectively. The activity and expression of MMP-2 and MMP-9 were examined by zymography, Western blot and RT-PCR, respectively. The activity of NF- κ B was examined by EMSA. Results EGF could significantly promote the invasiveness of pancreatic cancer cells but did not affect cell proliferation or adhesion. The expressions of NF- κ B and MMP-9 were significantly increased by EGF, but EGF did not affect the activity and expression of MMP-2. Furthermore, EGF stimulated the NF- κ B binding activity. Pretreatment with NF- κ B inhibitors, pyrrolidine dithiocarbamate (PDTC), could significantly inhibit the activity of NF- κ B induced by EGF. Meanwhile, the EGF-induced expression and activity of MMP-9, as well as cell invasiveness were also inhibited by NF- κ B inhibitor. Conclusion EGF could increase the expression and promote the invasiveness of MMP-9 via the activation of NF- κ B in pancreatic cancer cells, which implies that NF- κ B inhibitant, such as PDTC, may diminish the invasiveness of pancreatic cancer cells.
OBJECTIVE:To investigate the diagnostic meaning of MRI in intraocular tumors.
METHODS:Forty-six cases of confirmed intraocular tumors,including choroidal melanoma(20 cases),retinoblastoma(18 cases),Coats disease(6 cases)and choroidal hemangioma(2 cases),were studied with MRI and compared with ultrasonography and CT.
RESULTS:In making discoveries about intraocular tumors,there were no sighificant difference between MRI and B-ultrasonography or CT （P＞0.03，chi;2=1.0716）while there were highly statistic sighificance in dediding characters and position （P＜0.01，deceding character chi;2=29.8314，positionchi;2=13.659）of them.
CONCLUSION:Among the examinations to find out about the position,character and secondary pathological insults of in traocular tumors MRI might be more available than CT and ultrasonography.
（Chin J Ocul Fundus Dis,1997,13:93-95 ）
Objective Series of compl icated molecule signal pathway are involved in the bone regeneration. To explore the possibil ity of nuclear factore kappa B (NF-κB) which is taken as the “key activation” during the fracture healing and provide the laboratory evidence for the gene therapy of nonunion or delayed union of fractures. Methods Thirtythree adult male Wistar rats (weighing 180-220 g) were selected and divided randomly into 4 groups: group A (the control group, n=3), the rigth lower segments of radius were injected with normal sal ine 0.3 mL for 7 days, once per day; group B (Bay 11-7082 injection group, n=6), the middle and distal radius were injected with normal sal ine containing 50 μmol/L NF- κB inhibitor Bay 11-7082 0.3 mL for 7 days, once per day; group C (fracture group, n=12), the right middle and distal radius were cut by a sharp scissors to form per fracture model; and group D (Bay 11-7082 treatment group, n=12), based on group C, 0.3 mL of 50 μmol/L Bay 11-7082 were injected into the fracture site for 7 days, once per day. The callus tissues were harvested at 3, 7, 14, and 28 days after fracture for Western blot analysis, alkal ine phosphatase (ALP) activity assessment, prostaglandins E2 (PGE2) production assay, and histological observation. Results The rats of all groups were survivaltill the experiment completion. At 3 and 7 days after injection, there was no significant difference in the ALP activity and PGE2 production between group B and group A (P gt; 0.05); but group C was significantly higher than group A (P lt; 0.01) and group D was significantly lower than group A (P lt; 0.01). The expressions of NF-κB p65, bone morphogenetic protein 7 (BMP-7), and inhibitor of DNA binding 2 (Id2) were observed at fracture sites of 4 groups. There was no significant difference in the expressions of NF-κB p65, BMP-7, and Id2 between group B and group A (P gt; 0.05); the expressions of NF-κB p65 and BMP-7 were significantly higher and the expression of Id2 was significantly lower in group C than group A (P lt; 0.01); and the expressions of NF-κB p65 and BMP-7 were significantly lower and the expression of Id2 was significantly higher in group D than group A (P lt; 0.01). The histological observation showed that a lot of osseous callus formed in group C at 14 and 28 days, but osseous callus just began to form in group D at 28 days. Conclusion NF-κB p65 can facil itate early fracture heal ing of rat radius by elevating the PGE2 production and regulating BMP-7 and Id2 expression.
Objective To investigate the effects of simvastatin on lung tissue in septic rats by observing the protein expression of nuclear factor kappa B ( NF-κB) and pathologic changes in lung tissue at different time points. Methods 90 healthy male Sprague-Dawley rats were randomly divided into three groups ( n =30 in each group) . All the rats received administration by caudal vein and capacity volume is 2 mL. The rats in the control group were treated with saline ( 2 mL) . The rats in the LPS group were treated with LPS ( 5 mg/kg ) . The rats in the simvastatin group were treated with LPS ( 5 mg/kg) and simvastatin ( 20 mg/kg) . Six rats in each group were killed randomly at 2, 4, 6, and 12 hours after the injection, and the right middle lobe of lung was taken out. Pathological changes of lung tissue wee investigated under light microscope. The expression of NF-κB in lung tissue was determined by immunohistochemistry ( IHC) method. Results Microscopic studies showed that there were not pathological changes in the lung tissue of rats in the control group. While in the LPS group, the alveolar spaces were narrowed and the alveolar wall were thickened. Furthermore, severe interstitial edema of lung and proliferation of epithelial cells were observed. In the simvastatin group, the degree of the infiltration of leukocytes and the lung interstitial edema were less severe than those in the simvastatin group. In the control group, the expression of NF-κB protein in most of lung tissue was negative. In the LPS group, the expression of NF-κB protein was detected at 2h, andreached the peak at 6h, then decreased at 12h. In the Simvastatin group, the NF-κB expression was significantly lower than that in the LPS group at all time points ( P lt; 0. 01) . Conclusion Simvastatin can ameliorate pathological lesions and decrease expression of NF-κB in lung tissue of septic rats.
Objective To investigate the molecular mechanism of multiple cellular factors expressed shortly after ischemia reperfusion (IR) injury from the pathway of nuclear factor kappa B (NF κB). Methods The isolated heart models were established and sixty six rats were randomly divided into experimental group and control group. The deoxyribonucleic acid (DNA) binding activities of NF κB, the inhibitory kappa B (IκBα) levels in cytoplasm and tumor necrosis factor α (TNF α) messenger ribonucleic acid (mRNA) expressions were determined after 5, 15 min ischemia in experimental group, both after 0, 5, 15, 30 min ischemia and concomitantly 5, 15, 30, 45, 60 min reperfusion in control group. Results Augment of DNA binding activities of NF κB and reduction of IκBα in cytoplasm shortly after ischemia results were observed in control group. The level of IκBα was restored after reperfusion, the DNA binding activities of NF κB was further augmented. DNA binding activities of NF κB and TNF α mRNA expressions were lower in experimental group than those in control group. Conclusions NF κB in IR myocardium is activated by two different pathways: p65 p50 heterodimers and p50 p50 homodimers. In addition, the results suggest that early activation of NF κB induced by ischemia in the myocardium could be a signal mechanism for controlling and regulating immediate gene expressions during ischemia reperfusion.
ObjectiveTo investigate the relationship between alumina ceramic particles and aseptic loosening of the joint prosthesis and the effect of lanthanum chloride on the secretion of interleukin 1β (IL-1β) and tumor necrosis factor α (TNF-α) of macrophage RAW264.7 induced by alumina ceramic particles.
MethodsRAW264.7 cells were cultured in vitro and divided randomly into 4 groups according to different culture solutions:blank control group (group A),1 mg/mL alumina ceramic particles (group B),1 mg/mL alumina ceramic particles and 10 μmol/L lanthanum chloride (group C),and 10 μmol/L lanthanum chloride (group D).The cell growth was detected by MTT,and ELISA,RT-PCR,and Western blot were used to test the expressions of IL-1β,TNF-α,and nuclear factor κB (NF-κB).
ResultsThere was no significant difference in cell growth among all groups by MTT (F=2.180,P=0.142).RT-PCR results showed that the expressions of IL-1β,TNF-α,and NF-κB mRNA in group B were significantly higher than those in the other 3 groups (P<0.05); the expressions in group D were significantly lower than those in group A (P<0.05).ELISA results showed that the contents of IL-1β and TNF-α in group B were significantly higher than those in the other 3 groups (P<0.05); the contents in group D were significantly lower than those in group A (P<0.05).Western blot analysis revealed that the expression of NF-κB protein in group B was significantly higher than that in the other 3 groups (P<0.05).
ConclusionAlumina ceramic particles can stimulate the secretion of IL-1β and TNF-α of macrophage,and lanthanum chloride can inhibit the secretion of IL-1β and TNF-α of macrophage.
Objective To observe the effects of exogenous pulmonary surfactant (PS) on ventilation-induced lung injury (VILI) in rats, and to investigate its possible mechanisms. Methods A total of 40 Wistar rats were divided into 4 groups with randomized blocks method: control group, high tidal volume (HV) group, VILI group, and PS group, with 10 rats in each group. The control group was subjected to identical surgical procedure but was never ventilated. After 30 min of mechanical ventilation (MV) with Vt 45 ml/kg, the rats in HV group were killed immediately; rats in the VILI group were continually ventilated for up to 150 min with Vt 16 ml/kg; in the PS group, 100 mg/kg of PS administered intratracheally and with the same settings as VILI group. Mean artery pressure (MAP), blood gas analysis, lung wet to dry weight ratios (W/D), thorax-lung compliance, and cell counts in bronchoalveolar lavage fluid (BALF) were determined. Nuclear factor-κB(NF-κB) activity in lungs was measured by enzyme-linked immunosorbent assay (ELISA), interleukin-8(IL-8) in serum and BALF was determined by radioimmunoassay (RIA). Pathological examination of the lung was performed. Results Injurious ventilation significantly decreased MAP and PaO2/FiO2, but increased NF-κB activity and W/D. MAP and PaO2/FiO2 improved, but NF-κB activity, IL-8 in serum and BALF, and cell counts in BALF reduced significantly in PS group compared with those in VILI group. Histological studies showed reduced pulmonary edema and atelectasis in the PS group. Conclusion PS administered intratracheally can suppress the increased activity of NF-κB induced by VILI, exogenous PS can be used to treat VILI.
Leber’s hereditary optic neuropathy (LHON) is a paradigm maternal hereditary eye disease, mainly involving the retinal and macular fibers of the optic disc in the anterior ethmoid plate of the sclera. LHON has the characteristics of sex bias among males and incomplete penetrance. Primary mitochondrial DNA mutations m.11778G>A, m. 14484T>C, m.3460G>A are the molecular basis of LHON. However, other risk factors, such as secondary mitochondrial DNA mutations, mitochondrial haplotypes, nuclear modification genes, estrogen, vitamin B12 and environmental factors, work together to affect its phenotypic expression. The clinical diagnosis of LHON mainly limited to the detection of the primary mutation site of mitochondrial DNA. Therefore, comprehensive analysis of multiple risk factors of LHON will facilitate to construct multi-dimensional model of prevention, diagnosis and treatment system, which provide accurate and individualized medical services for patients. These may alleviate the incidence in LHON families. It also provides new ideas and different angles for the in-depth study of the pathogenesis of LHON.
Objective To study the relationship between smoking as well as smoke cessation and lung inflammation of chronic obstructive pulmonary disease( COPD) , and its possible mechanism. Methods Thirty-two Wistar rats were randomly divided into a control group, a low-dose smoking group, a high-dose smoking group, and a smoke cessation group. The expressions of NF-κB and E-selectin in rats lung were detected by immunohistochemistry and hybridization in situ. Results The mRNA and protein expressions of NF-κB in bronchial endothelial cells of the high-dose smoking group( 0. 43 ±0. 01, 0. 41 ±0. 04) , the lowdose smoking group( 0. 41 ±0. 01, 0. 40 ±0. 01) , and the smoke cessation group( 0. 39 ±0. 01, 0. 37 ±0. 03) , were significantly higher than the control group( 0. 29 ±0. 06, 0. 28 ±0. 06) ( all P lt; 0. 05) , with the high-dose smoking group and the smoke cessation group significantly higher than the low-dose smoking group ( both P lt;0. 05) . The mRNA and protein expressions of E-selectin had the similar pattern with NF-κB. The expressions of E-selectin mRNA and protein were positively correlated with the expression of NF-κB mRNA and protein respectively ( r = 0. 80, r = 0. 89, P lt; 0. 01) . Conclusions Smoking can result in high expressions of NF-κB and E-selectin in a dose dependent manner. Smoke cessation can relieve airway inflammation and is an effective measure for preventing COPD.
【Abstract】 Objective To study the effects of ischemic preconditioning (IP) on the activity of nuclear factor-κB （NF-κB） and the expressions of TNF-α and intercellular adhesion molecule-1 (ICAM-1) during early reperfusion following liver transplantation in rats. Methods The models of rat orthotopic liver transplantation were established. The donor livers were stored for 2 hours in Ringers solution at 4 ℃ before transplantation. All rats were randomly divided into sham operation group （SO group）， control group and IP group. IP group was achieved by clamping the portal vein and hepatic artery of donor liver for 10 minutes followed by reperfusion for 10 minutes before harvesting. The activity of NF-κB and expressions of TNF-α and ICAM-1 at 1 h, 2 h, 4 h and 6 h after reperfusion were measured. Serum ALT, LDH were also determined. Results The liver function of recipients with IP were significantly improved. Compared with SO group， the graft NF-κB activity increased after transplantation in control group and IP group (P＜0.05), while compared with control group that was significantly attenuated at 1 h and 2 h in IP group. Similarly, hepatic levels of TNF-α and ICAM-1 were significantly elevated in control group and were reduced in IP group. Conclusion IP might down-regulated TNF-α and ICAM-1 expression in the grafts after orthotopic liver transplantation through depressed NF-κB activation， and attenuate neutrophil infiltration in the grafts after reperfusion.
