There are many type Ⅱ toxin-antitoxin(TA) systems in Mycobacterium tuberculosis(Mtb), among which the VapBC family is the most abundant TA system including toxin VapCs and antitoxin VapB. Toxin VapCs are usually ribonucleases(RNases) with a PilT N-terminal(PIN) domain that can cleave tRNA or sarcin-ricin loop(SRL) of 23S rRNA to exert the toxicity. Antitoxin VapB regulates the expression level of homologous toxins by binding to promoter DNA or directly binds to homologous toxins to inhibit their toxicity. The VapBC family is closely associated with the growth, pathogenicity and drug resistance of Mtb. Therefore, the function of Mtb VapBC family, substrate specificity of toxin VapCs, structures of VapBC,and structure-based drug development were summarized in this paper, in view to providing new ideas for the treatment of tuberculosis(TB).

Objective To explore the different characteristics of tumor recurrence after liver transplantation (LT)and hepatectomy(HC)in patients with hepatocellular carcinoma(HCC).Methods The literatures about tumor recurrence of HCC after LT and HC were reviewed and their characteristics were compared.Results There are distinctions of recurrence rates,time,common sites between the recurred tumors after LT and HC,and their correlation factors and mechanisms of recurrence are also different.Conclusion Preventive measures should be strengthened and treatments should be more targeted according to the different characteristics of tumor recurrence after LT and HC to improve postoperative life quality and increase the survival rate.

Humans ; Occupational Diseases ; diagnosis

Falling in the elderly is a major health problem and may cause severe consequences. Fall risk assessment is important for preventing and intervening fall incidence. Inertial Measurement Unit (IMU) has been introduced to evaluate motion/balance function and fall risk among the older people. Some researches indicated that it might have advantages over the usual tools, and can be used in the hospitals, communities, nursing homes, etc. IMU is a good way to measure gait variability, which may be strongly related with the risk of falls.

Breast Neoplasms ; pathology ; surgery ; Carcinoma, Ductal, Breast ; pathology ; surgery ; Cryoultramicrotomy ; Cytodiagnosis ; methods ; Female ; Histocytological Preparation Techniques ; methods ; Humans ; Intraoperative Care ; methods ; Precancerous Conditions ; pathology ; surgery

Foreign Bodies ; complications ; diagnosis ; Glottis ; Hoarseness ; diagnosis ; etiology ; Humans ; Male ; Middle Aged

Objective To observe pathological process of intestinal epithelial cells subjected to ischemia,ischemia/reperfusion injury and inflammation simulated hypoxia/reoxygenation (H/R) and lipopolysaccharide (LPS) challenged human fetal normal colonic cell (FHC) line in vivo,and to observe the changes when the assaulted intestinal epithelial cells were treated with emodin,in order to explore the possible intervention targets of emodin.Methods Normoxia group:the FHC cells were cultured in 95％ air and 5％ CO2 at 37 ℃.Hypoxia (H) group:the cells were cultured with a mixed anaerobic gas of 1％ O2,5％ CO2 and 94％ N2 at 37 ℃ for 1,2,3,4 hours.H + LPS group:the cells were cultured in hypoxic condition as H group with simultaneous challenge of LPS (1 mg/L).H/R group:the cells were cultured in hypoxia for 3 hours followed by reoxygenation for 1,2,3 and 4 hours,respectively.H/R + LPS group:the cells were cultured in H/R as H/R group and LPS (1 mg/L) simultaneously.Emodin intervention group:the cells were cultured in H3 h/R2 h + LPS and emodin (20,40,60,80 μmol/L) simultaneously.The variation trends of phosphorylation nuclear factor-κB profilin-o (pIκB-α),phosphorylation NF-κBp65 (pNF-κBp65) and their downstream target gene cyclooxygenase-2 (COX-2),and hypoxia-inducible factor-1α (HIF-1 α) were determined by Western Blot.The morphological changes in intestinal epithelium in different groups were observed using light microscope.The effect of emodin on the proliferation of intestinal epithelial cell was measured by methyl thiazolyl tetrazolium (MTT) assay.Results ① H group:the expressions of pIκB-α,pNF-κBp65 and COX-2 were upregulated,peaking at H1 h (0.350 ± 0.018,1.083 ± 0.054,0.903 ± 0.045),and then they gradually lowered (F value was 3.011,7.247,5.754,P value was 0.013,0.000,0.005,respectively).The expression of HIF-1 α peaked at H3 h (1.511 ± 0.076),but there was no significant difference among different groups (F=1.881,P=0.062).H + LPS group:the expressions of pIκB-α,pNF-κBp65,COX-2,HIF-1α were increased with elongation of duration of hypoxia,and a maximal induction was observed at H3 h (0.504 ± 0.025,1.255 ± 0.063,0.812 ± 0.041,1.209 ± 0.075,F value was 2.683,8.774,9.765,2.432,and P value was 0.011,0.000,0.000,0.026,respectively).H/R group:with the prolonged duration of reoxygenation,the expressions of NF-κB signaling pathway proteins (pIκB-α,pNF-κBp65,COX-2) were decreased and dropped to nadir at H3 h/R4 h (0.712 ± 0.034,1.202 ± 0.048,0.691 ± 0.042,F value was 1.923,6.765,2.719,and P value was 0.063,0.000,0.016,respectively).Compared with H group,HIF-1α was decreased with a prolonged duration of reoxygenation in H/R group,but there was no significant difference in value among different time points (F=1.280,P=0.081).H/R + LPS group:pIκB-o,pNF-κBp65,COX-2,HIF-1α showed no sign of degradation with the prolonged duration of reoxygenation,and their expression increased to maximum analogously at R2-3 h (3.302 ± 0.061,2.315 ± 0.055,2.017 ± 0.043,2.413 ± 0.098,Fvalue was 4.614,1.652,5.970,2.076,and Pvalue was 0.001,0.067,0.000,0.037,respectively).Emodin group:emodin when co-treated with H/R + LPS inhibited the expression of HIF-1o and NF-κB pathways with a dose-effect relationship (P＜0.05 or P＜0.01).Emodin at the dose of 80 μmol/L showed most marked inhibition (2.599 ± 0.130,1.772 ± 0.089,2.590 ± 0.129,2.518 ± 0.125).However,after treatment of emodin did not show such effect.② After treatment with H/R + LPS,there were morphological changes in cells:vacuoles,deformation and fusion.The speed of cell growth became much slower compared with H group.③ Emodin (20-80 μmol/L) had no significant effect on cell proliferation.Although emodin produced biological effect in this concentration range,it had no cellular toxicity.Conclusions Both hypoxia and inflammation can activate the hypoxia pathway of HIF-1α and the pro-inflammatory pathway of NF-κB,but different stimuli cause varying degrees of activation in these two pathways.In H/R group,both pathways were weakened during reoxygenation.However,in H/R + LPS group,the proteins remained to show a relatively high expression during the process of reoxygenation.This may be related to the pathophysiological mechanism of intestinal ischemia/reperfusion injury:hypoxia/reperfusion injury and LPS act together to destroy the intestinal epithelial cells and induce gut-derived sepsis.Emodin may inhibit inflammation by blocking HIF-1α/NF-κB-COX-2 signaling pathways.

The mode of long-chain alkane uptake by Pseudomonas aeruginosa (CGMCC 1.1785) was studied. P. aeruginosa 1.1785 is capable of using solid long-chain alkane as sole carbon source and producing surface active compound as metabolite. The mass transfer limitation in uptake of alkane was confirmed from the observation that interfacial area of eicosane with water dominates the growth rate of this strain. The enhancement of eicosane uptake by rhamnolipid was mainly caused by increase of interfacial area, since the pseudosolubilized alkane can not support the growth of P. aeruginosa 1.1785. Cell surface hydrophobicity was increased dramatically at the initial phase of growth and followed by a gradual decrease, which indicates that different modes are employed by P. aeruginosa 1.1785 at different growth phase. Therefore, the surfactant mediated mode can be negligible in the uptake process, while the directly attachment mode may not work throughout the growth of P. aeruginosa 1.1785. We proposed a novel uptake mode, in which the chemotaxis of this strain plays an important role.

To explore the effects of angiotensin Ⅱ on plasminogen activator inhibitor 1 (PAI 1) gene expression in human glomerular mesangial cells.Glomerular mesangial cells (GMCs) were cultured from a healthy adult human kidney (unsuitable for renal transplantation) and then treated with angiotensin Ⅱ at concentration of 10 -9 ,10 -8 , 10 -7 and 10 -6 mol/L, respectively. The mRNA expressions of angiotensinⅡAT1 and AT2 receptor, and PAI I were examined with RT PCR and Northern blot analysis, respectively. Plasminogen activator activity in the supernatants of the GMCs was measured with fibrin plate method. After the GMCs were stimulated by angiotensin Ⅱ, the mRNA level of the AT1 receptor was markedly enhanced, but the AT2 receptor mRNA level was still undetectable as that in normal condition. When GMCs were treated with angiotensin Ⅱ for 48 hours, PAI 1 mRNA expression was increased in a dose dependent manner. The plasminogen activator activity was significantly reduced in the supernatants of the angiotensinⅡ treated GMCs. the results suggested that angiotensinⅡ promote PAI 1 gene expression of the GMCs possibly through its AT1 receptor.