Morphological observation of human gastric cancer cell SGC-7901 clones and identification of gastric cancer stem cells / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To dynamically investigate the morphology of human gastric cancer SGC-7901 cell clones, and then compare the tumorigenic ability of different clones in order to identify the tumor stem cell clones.</p><p><b>METHODS</b>Clones derived from gastric cancer SGC-7901 cells were assessed by morphological observation, and the clone formation rate and proportion of each clone were calculated. The expression of CD44 and CDX2 in different clones was detected by immunofluorescence microscopy and Western blot. Furthermore, different clones were isolated and cultured, and their self-renewal property was assayed. Cells of different clones were subcutaneously inoculated into nude mice and the tumorigenic ability of each group was determined.</p><p><b>RESULTS</b>Clones derived from gastric cancer SGC-7901 cells had three types, i.e. clones of tight, transitional and loose types. The total clone formation rate was (9.80 ± 1.07)%, and the proportion of tight, transitional and loose type clones was 10.2%, 56.0% and 33.8%, respectively. The results of immunofluorescence microscopic examination showed that the signal of CD44 was significantly stronger in the tight clones than in the transitional and loose clones, however, the signal of CDX2 was weakest in the tight colonies. The results of Western blot were consistent with that of immunofluorescence microscopic observation. SGC-7901 cells of tight clones possessed strong ability of self-renewal and in vivo tumorigenicity in the nude mice.</p><p><b>CONCLUSION</b>SGC-7901 cell clones vary in morphology and differentiation, and the tight type clones may include rich gastric cancer stem cells.</p>

Influence of aminoguanidine on retina morphology and expression of nitric oxide and inducible nitric oxide synthase after retina ischemia-reperfusion injury / 中华实验眼科杂志

Background Many eye diseases such as central retinal artery occlusion,glaucoma and ischemic optic neuropathy,etc.lead to retinal ischemia-reperfusion injury (RIRI) and furthmore visual functional damage.It is neeessary to study the treatment of RIRI.Objective This study was to observe and discuss the influence of aminoguanidine on the retina morphological changes and its mechanism after RIRI.Methods Eighty clean healthy male Japanese white rabbits were randomly divided into normal injury group,RIRI group and aminoguanidine (AG)treated group.The model of RIRI was established by infusing saline solution into the anterior chamber to elevate intraocular pressure (IOP) in both RIRI group and AG group.AG was intraperitoneally injected in the models of the AG group,and normal saline solution was used at the same method in tbe normal group and the RIRI group.The fundus photography and fundus fluorescein angiography(FFA) were pertormed on the rabbits at the moment of retina ischemia and 6,24 and 72 hours after reperfusion.The parts of rabbits were sacrificed 1,6,24 and 72 hours after reperfusion,followed by the enucleation of the eyeballs.Retinal section was prepared for TUNEL examination to evaluate the apoptosis of retinal cells.Nitric oxide (NO) concentration in retina was detected with nitrate reductase,and the activity of inducible nitric oxide synthase (iNOS) was measured by colorimetric detection.The use of the animals followed the Regulations for the Administration of Affairs Concerning Experimental Animals by State Science and Technology Commission.Results The fundus photography and FFA showed that the retinal edema was more mild,and the percentage of vascular occlusion was lower in the AG treatment group than that in RIRI group and the amount and area of fluorescein leakage were also smaller than the treatment group.The numbers of TUNEL positive cells in the AG treatment group were less than those in the RIRI model group at 1,6,24 and 72 hours after experiment (F分组 =2762.37,P =0.00 ; F时间 =894.24,P =0.00).Numbers of TUNEL positive cells between adjacent time points were significantly different in both RIRI model group and AG treatment group (RIRI group:q =24.475,36.591,-20.37,P＜0.05;AG group:q =20.94,16.79,-6.92,P＜0.05),with the peak value at 24 hours after experiment.NO contents were significantly higher in the RIRI model group compared to AG group at various time points(q =3.84,4.01,8.91,3.75,P＜0.05),and those between adjacent time points showed significant differences (RIRI group:q=4.77,13.403,-10.29,P＜0.05;AG group:q=4.55,9.05,-5.08,P＜0.05).iNOS activity was significantly elevated in the RIRI model group compared with AG group(q=-3.74,-4.94,-6.53,-3.98,P＜0.05),and obvious differences also were seen between the adjacent time points in both two groups(RIRI group:q =8.43,6.71,-6.39,P＜0.05 ;AG group:q =4.16,5.08,-3.93,P＜0.05).Conclusions Aminoguanidine can protect the retinal function and morpbology from oxidative stress damage after RIRI by reducing the NO level and inhibiting the iNOS activity in retina.

Effects of taurine on TNF-alpha and NF-kappaB expression of liver injury after limbs ischemia/reperfusion in rats / 中国应用生理学杂志

<p><b>AIM</b>To investigate the effect of pretreatment with taurine on liver injury changes and the change of tumor necrosis factor alpha and NFkappaB expression following rats limbs ischemia/reperfusion.</p><p><b>METHODS</b>The model of limbs ischemia/reperfusion injury on rats was adopted in the experiment. Wistar rats were randomized into 4 groups (n = 10): Control group, T group, I/R group and TR group. Levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST) and MDA in the plasma, MDA, MPO, calcium in liver tissues were measured by colorimetric method. The content of TNF-alpha in plasma and liver tissues was determined by radioimmunoassay. The morphologic changes were observed with HE staining. The expressions of NF-kappaBp65 in liver tissues were tested by immuno-histochemistry method.</p><p><b>RESULTS</b>It was found that against the control group, the test values of ALT, AST, et al. and expressions of TNF-alpha, NF-kappaB increased in I/R group and TR group, but values of those in TR group were lower than in I/R group.</p><p><b>CONCLUSION</b>Taurine can decrease the levels of TNF-alpha and NF-kappaB. It can mitigate the liver injury after limb ischemia/reperfusion injury in rats.</p>

Effect of ischemic preconditioning on lung injury induced by ischemia/reperfusion in the hind limbs of rats / 中国应用生理学杂志

<p><b>AIM</b>To study the effect of ischemic preconditioning on lung injury following ischemia/reperfusion (I/R) in the hind limbs of rats.</p><p><b>METHODS</b>Wistar rats were randomly divided into four groups (n=8): control group,limbs ischemia/reperfusion (LI/R) group, ischemia preconditioning (IPC) group and L-NAME group. At the end of the experiment, blood/gas analysis and the contents of serum MDA, NO, ET and lung tissue MDA, NO, ET, MPO were measured. Meanwhile, lung index and W/D) of lung were measured.</p><p><b>RESULTS</b>After the rats' hind limbs suffered ischemia/reperfusion, the level of PaO2 decreased and the values of W/D, LI, MPO of the lung issure and MDA, NO, ET of plasma and lung all increased significantly in the LI/R group; but the ratio of NO/ET decreased. Compared with LI/R group, the contents of NO and ratio of NO/ET increased but other parameters decreased in the IPC group. Compared with IPC group, the contents of NO and ratio of NO/ET decreased, but other parameters increased in the L-NAME group.</p><p><b>CONCLUSION</b>The IPC can attenuate lung injury following IR in the hind limbs of rats, which may correlated with the increase of NO.</p>

The affection and significance of NO on the expression of P-selectin in renal injury following hind limb ischemia/reperfusion in rats / 中国应用生理学杂志

<p><b>AIM</b>To probe into the affection and significance of NO on the expression of P-selectin in renal injury following hind limb ischemia/reperfusion in rats.</p><p><b>METHODS</b>In accordance with the conventional approaches of our department, the model rats were prepared after they were made to undergo 4 hours or ischemia followed by 4 hours of reperfusion of hind limbs. The Wistar rats were divided into four groups randomly: Control group, LI/R group, L-Arg group and L-NAME group. And then in those four groups of Wistar rats, a series of values of measurement were determined such as: Plasma concentrations of nitric oxide (NO), blood urea nitrogen (BUN) and creatinine (Cr). Furthermore, biochemically there came to the assessment of the values including myeloperoxidase (MPO), NO, total nitric oxide synthase (tNOS), inducible NOS (iNOS) and constitutive NOS (cNOS) of renal tissue in different groups. By the methods of electrophoresis and biochemistry, the urine protein was mensurated. The immunohistochemical method was used to detect the expression of P-selectin protein. The morphologic changes were observed with a microscope.</p><p><b>RESULTS</b>After hind limbs had suffered from ischemia/reperfusion for 4 hours, there was the occurrence of a series of results such as in the following which were based on the comparison between plasm of LI/R group and control group. The values of NO, BUN and Cr increased significantly, and the trend of indexes such as NO in renal tissue was similar to that in plasma. The values of MPO, tNOS and iNOS in renal tissue all increased significantly after reperfusion, while cNOS decreased distinctly. The urine protein appeared, especially large molecular weight protein. Renal pathology revealed that after LI/R there were edema and infiltration of polymorphonuclear neutrophil (PMN). Immunohistochemically, the expression of P-selectin was upregulated significantly. Compared with LI/R rats, all injury changes were alleviated in L-Arg group. Morphologic changes were mild. Both the content of urine protein and the percentage of apoptosis cell decreased. The expression of P-selectin was downregulated. In L-NAME group, all injury changes got worse. Immunohistochemical results showed strong positive staining of P-selectin.</p><p><b>CONCLUSION</b>The renal injury after LI/R may relate to the strong expression of P-selectin. NO may have protective affection by decreasing the expression of P-selectin and alleviating the adhesion, aggregation and infiltration of neutrophils.</p>