AIM：To investigate the role of NF-κB in the activation of inducible nitric oxide synthase (iNOS) gene by tumor necrosis factor alpha (TNF α) and lipopolysaccharide (LPS) in endothelial cells and effect of antioxidant on the induction of iNOS. METHODS：Rat pulmonary microvascular endothelial cell (RPMEC) was cultured and the cells were identified with antiendothelial cell antibody CD31 using immunohistochemistry(ABC). The concentration of nitrite in the culture media was determined based on Griess reaction. iNOS mRNA was analyzed using RT-PCR and Northern blot. NF-κB in cell nuclei was detected with electrophoresis mobility shift assay (EMSA). RESULTS：A marked production of nitrite in RPMECs was found after 24 hours treatment with TNF α(105 U/L) and LPS (1 mg/L) (P＜0.01). The level of iNOS mRNA increased significantly after adding TNF α(105 U/L) and LPS (1 mg/L) to the cell media for 2 hours (P＜0.05). Pretreatment with cycloheximide (CHX, 10 mg/L) or antioxidant, PDTC (0.1 mmol/L) or NAC (20 mmol/L) significantly decreased nitrite production and iNOS mRNA expression induced by TNF α(105 U/L) and LPS (1 mg/L) (P＜0.05). Furthermore, there was a dose-effect relationship between PDTC/NAC and inhibitory effect. TNF α (105 U/L) and LPS (1 mg/L) triggered the activation and translocation of NF-κB. This effect was blocked by adding PDTC (0.1 mmol/L) or NAC (20 mmol/L) to the cell media for 1.5 hours.CONCLUSION：1.TNFα and LPS may induce iNOS gene expression at transcriptional or posttranscriptional level. The upregulation of iNOS depends on new protein synthesis. 2. The induction of iNOS gene expression by TNFα and LPS is dependent on the activation of NF-κB. 3. Antioxidants may inhibit the induction of iNOS gene through the inhibition of NF-κB activation.

Microvascular endothelial cell (MVEC) is one of the target cells of TNFα (TNF effect). The dysfunction of MVEC induced by TNF plays an important role in some cardio-cerebral vascular diseases. ① Cell proliferation kinetic: Using flow cytometry, we found cell count ［(4.30±0.34)×107／L)］ in TNF group (4×105 U/L) was obviously less than that in control ［(5.23±0.50)×107／L, P＜0.01］. The cells of G1 phase were more than those of the control, while the cells of G2, S and M phase became less (P＜0.05). ② Coagulant and anticoagulant: 72 h after MVEC cultued in the media, the content of 6-keto-PGF1α (RIA) and activity of PAI decreased significantly in TNF (4×105 U/L) group (P＜0.01, vs control). The difference between TXB2 content and t-PA activity in groups was not significant (P＞0.05). ③ Adhesive molecule: The effect of low concentration TNF (＜4×105 U/L) on adhesion between cultured MVEC and leukocytes was not signficant, but when the concentration of TNF reached 8×105 U/L or more, 12 h after culture the adhesion rate between MVEC and neutrophil increased 30.8%±4.5%. If adding monoclonal antibody of ICAM-1/CD11 into media, the adhesion rate of leukocytes decreased significantly (from 31.2% to 63.4%). ④ NO: The level of nitrite in culture media (Griess reaction) was higher than that of control (P＜0.05) after pretreatment of TNF (2×106 U/L) for 6 h. Adding L-NMMA, Dexamethasone or Cycloheximide in media could block the increase of nitrite induced by TNF, while L-Arg could enhance it. The expression of iNOS mRNA of PMVEC increased significantly after treated with TNF (2×106 U/L) for 24 h (quantitative RT/PCR). Pretreatment with Dexamethasone or Cycloheximide could block the increase (P＜0.05). Meanwhile, the expression of eNOS mRNA decreased significantly compared with control, the decrease can be blocked by Cycloheximide but not by Dexamethasone. So that TNF can induce the expression of iNOS mRNA in PMVEC, but inhibited the expression of eNOS mRNA. NO production in PMVEC can be time-dependently induced by TNF. ⑤ Apoptosis: Adding high concentration TNF(＞1.2×106 U/L) in culture media for 12 h can induce apoptosis of PMVEC with electron microscopy, flow cytometry (PI/AnnexinV stain), TUNEL and DNA ladder eletrophoresis. Meanwhile, expression of apoptosis-associated gene Bcl-2 mRNA decreased and that of Fas mRNA increased (Northern blot). The expression of FADD, caspase 3 and caspase 8 enhanced too. So that signal of apoptosis induced by TNF may be transmitted following the cascade of Fas→FADD→caspase8→caspase3. In conclusion, it should be paid attention to metabolism inability and dysfunction induced by TNF which can not found easyily using light microscope. High concentration TNF can induce apoptosis of endothelial cells regulated by apoptosis-associated genes. The changes mentioned above are common pathway in pathogenesis of some diseases related to TNF.

AIM:To investigate the role of nuclear factor ?B (NF ?B) in the induction of iNOS gene by TNF? and LPS in endothelial cells and the effect of antioxidant on the induction of iNOS. METHODS:Nitrite was determined based on Griess reaction. iNOS mRNA was analyzed using Northern blot. NF ?B in the cell nucleole was detected with electrophoretic mobility shift assay.RESULTS:(1)NO production and iNOS mRNA expression induced by LPS and TNF? was blocked by pyrrolidine dithiocarbamate(PDTC) or N-acetylcysteine(NAC). (2)LPS and TNF? triggered the activation and translocation of NF ?B, and PDTC or NAC inhibited the activation of NF ?B induced by LPS and TNF?.CONCLUSIONS:(1)The induction of iNOS gene by TNF? and LPS is dependent on the activation of NF ?B.(2)Antioxidants may inhibit the induction of iNOS gene through the inhibition of NF ?B activation.

Objective To evaluate the clinical value of CT angiography (CTA) in the diagnosis of acute pulmonary embolism (APE) after standardized chest pain assessment in patients with acute chest pain.Methods From January 2014 to May 2016,The clinical data of 43 patients with acute chest pain in Wuzhou Hospital of Traditional Chinese Medicine and Wuzhou Worker's Hospital received CTA examination were retrospectively analyzed.After standardized assessment,16 patients with suspected APE through pulmonary artery CTA scan screening were selected as observation group.27 cases of chest pain who were not received standardized assessment were selected as the control group,the chest CTA scan was used to investigate the causes of chest pain.The number of CTA confirmed by APE in two groups was compared.The effect of APE screening scale score and D-Dimer on the diagnosis of APE in the observation group was analyzed,and the application value of standardized evaluation of chest pain in APE was analyzed.Results The positive rate of CTA in the observation group was higher than that in the control group,and the difference between the two groups was statistically significant(x2 =3.93,P ＜ 0.05).The APE screening scale and D-Dimer in the observation group were (9.64 ±4.74) points and (886.73 ± 191.83) μg/L,respectively.which in the APE excluded patients were (2.20 ± 1.64) points,(587.20 ± 35.79) μg/L,respectively,the differences were statistically significant(t =3.363,3.402,all P ＜ 0.01).Conclusion Patients with acute chest pain and chest pain are standardized after the evaluation,optimization of CTA examination and improve the diagnostic rate of APE,reduce the rate of misdiagnosis and missed diagnosis,provide timely and accurate diagnostic basis for clinicians to gain valuable opportunity for further disposal.

Objective:To explore the influencing factors of acute rejection (AR) within one year after pediatric kidney transplantation (KT) and the effect of AR onset time on prognosis.Methods:From January 2011 to October 2021, a total of 112 patients aged under 18 years at the time of transplantation were selected.After excluding 6 of them with early renal non-function caused by non-rejection, 106 cases were examined.There were 63 males and 43 females with the age of 15(12, 16) years.The donors were living related (n=26) and deceased (n=80).According to the presence/absence and onset time of AR, they were assigned into three groups of AR within one year, AR after one year and non-AR.The relevant clinical data of donor/recipient, influencing factors of AR and therapeutic outcomes of AR were retrospectively compared.One-way ANOVA or Kruskal-Wallis test was utilized for comparing 1-year renal function after the occurrence of AR among three groups.With graft-function loss as an end-point event of follow-up, the effects of AR within one year and AR after one year on survival rate and function of graft-kidney were analyzed by Kaplan-Meier survival curve.Results:The median follow-up period of 106 pediatric KT recipients was 35 months.During follow-ups, 19 episodes of AR occurred in 17(16.0%) patients and 89 recipients exhibited no AR episode by the end of follow-up (non-AR group).As for initial AR, 9 episodes of AR occurred within one year (AR within one year group) and 8 episodes of AR after one year (AR after one year group).After anti-rejection treatment, 8 patients (47.1%) achieved full recovery and 6 patients (35.3%) failed to completely normalize and 3 patients (17.6%) developed graft failure.Univariate analysis indicated that, as compared with non-AR group, female recipients, donors aged under 8 years and early postoperative infection with parvovirus B19 were risk factors of AR within one year ( P=0.032, P=0.039, P=0.047).Kaplan-Meier survival analysis revealed that the incidence rates of AR within one year in patients with donors aged under 8 years and early postoperative parvoviral infection were 14.5%(8/55) and 30.0%(3/10) respectively.They were significantly higher than 2.0%(1/51) and 6.3%(6/96) of patients with donors aged above 8 years and those without parvoviral infection ( P=0.012, P=0.004).With graft-function loss as an end-point event of follow-up, Kaplan-Meier survival analysis showed that 10-year kidney graft survival rate in AR within one year and AR after one year groups were 88.9% and 65.6%.Both were significantly lower than that in non-AR group (98.9%).And the inter-group differences were statistically significant ( χ2=4.286, P=0.038; χ2=7.787, P=0.005).However, no significant difference existed in survival rate between AR within one year and AR after one year groups ( P=0.689).One-way ANOVA and Kruskal-Wallis test indicated that estimated glomerular filtration rates at 3/6/12 months after an onset of AR in AR within one year group were (76.8±51.6), (80.6±56.6) and (85.6±40.2) ml·min -1·1.73 m -2.The values of 3/6 months were lower than (125.3±39.2) and (124.7±38.2) ml·min -1·1.73 m -2 in AR after one year group.And the inter-group differences were statistically significant ( P=0.021, P=0.039).The values of 3/6/12 months were lower than (112.2±34.2), (115.3±33.2) and (117.4±30.2) ml·min -1·1.73 m -2 in non-AR group.And the inter-group differences were also statistically significant ( P=0.019, P=0.020, P=0.020). Conclusions:Female recipients, donors aged under 8 years and early postoperative infection with parvovirus B19 may elevate the risks of AR in children within one year of KT.AR within one year affects the survival rate of graft-kidney and renal function.

Based upon the experiences of planning and implementation of "Dynamic changes of Torque Teno virus load in Chinese renal transplant recipients with immunosuppressive therapy: A multi-center prospective observational double-blind cohort study", this article explored the current status and major difficulties of investigator-initiated multi-center prospective clinical trials of kidney transplantation in China. Various issues of organization design and implementation process management were discussed for enhancing the quality of implementing the relevant trials.