Bone marrow-derived mesenchymal stem cells (MSCs) have potentials of proliferation, multilineage differentiation and homing to injured tissue and organs. Therefore, many researchers consider them as seed cells and attempt to use them to repair injured tissues and organs. In the allo- even xero-transplantation of these seed cells, graft rejection is an important problem. A large amount of data show that MSCs have specific immune characteristics; they block dendritic cell maturation, decrease immune response of T cells, do not express class Ⅱ major histocompatibility complex molecules, and mediate immunosuppression by secreting some dissoluble factors. The specific low immunogenicity of MSCs could avoid rejection in xero-trensplantation for human and animals in vivo, showing advantages in treatment. Therefore, they are promising to be used as seed cells for kidney construction.

Objective To investigate the pathological characters of capillaries in tubulointerstitial nephropathy,and to study the expression of vascular endothelial growth factor(VEGF)and proliferation cell nuclear antigen(PCNA)in capillary endothelial cells in aristolochic acid-induced nephropathy in rat.Methods 46 male Wistar rats were randomly divided into 2 groups,the model group was composed of 26 rats which were gavaged with the extract of Caulis Aristolochiae Manshuriensis(aristolochic acid AA 20mg/kg?d),and the control group consisted of 20 rats which were treated with equal volume of potable water.The rats were sacrificed in batches at the end of 4th,8th and 12th weeks,and the blood samples were collected from abdominal aorta for the tests of renal functions.The kidney of each rat was harvested.The renal tissues were stained with HE,PAS,and Masson's technique for the analysis of degree of tubulointerstitial injury,interstitial fibrosis,and peritubular capillary(PTC),and the expressions of both VEGF and PCNA were morphologically observed and immunohistochemically analyzed.Results In the model group,the level of serum creatinine/body weight increased markedly,the renal pathological changes consisted of severe acute renal tubulointerstitial damage with cloudy swelling of tubule,degeneration,and exfoliation.With prolongation of feeding time,the damage progressively aggravated,and showed a remarkable tubulointerstitial injury.The interstitial fibrosis area was 31.36% at the end of 12th week.The renal capillaries showed thickening of vessel wall,narrowing of the vessel cavity,obstruction or hyalinization of some capillaries.There was focal infiltration of inflammatory cells around the injured vessels.But there was no apparent change in the globules compared with that in control group.The PTC dwindled in caliber or distorted,and the PTC density decreased significantly in models,especially in the region of tubular damage or interstitial fibrosis.The expression of VEGF showed compensatory up-regulation at the 4th week,but it was down-regulated gradually.The expression of PCNA was up-regulated at the 4th week,but down-regulated after 8th week,and only a few basement membrane naked tubular cells showed positive expression at 12th week.Conclusion AA could induce injury and loss of capillaries of the kidney.The decrease in capillary density might contribute to the impairment of renal function and progressive interstitial fibrosis,and the relative deficiency of VEGF expression may be related to PTC injury,which is one of the causes of chronic progression of aristolochic acid nephropathy.

Objective To establish the experimental animal model of acute tubular necrosis (ATN) in rats induced by caulis aristolochiae manshuriensis (CAM) containting aristolochic acid (AA) and compare the interventional effects among ligustrazine, prednisone and benazepril. Methods Male SD rats were divided randomly into six groups, 12 rats in each group. Control group, model group, prednisone group, benazepril group, ligustrazineⅠgroup and ligustrazineⅡgroup were given respectively by gavage with 3 ml/d distilled water,5 g?kg-1?d-1 CAM decoction (CAM 2 g/ml, AA 0.54 mg/ml, AA-Ⅰ0.46 mg/ml) for 60 days, then 3 ml/d distilled water, 10 g?g-1?d-1 CAM decoction for 30 days. Two hours after CAM gavage, control group and model group were given with normal saline. Prednisone group, benazepril group, ligustrazine group and ligustrazineⅡgroup were given with prednisone 5 mg?kg-1?d-1, benazepril 1.7 mg?kg-1?d-1, ligustrazine 50 mg?kg-1?d-1, ligustrazine 150 mg?kg-1?d-1 respectively by gavage for 90 days. Histopathology of kidney tissue was examined after 90 days. Results The renal tissue of control group was normal. Light microscopy of model group revealed patchy vacuolar changes of cells from proximal convoluted tubular epithelium, disorder and loss of brush border, exfoliated epithelial cells in the lumina, exposure of areas of denuded and rupture and thickness and atrophy of tubular basement membrane (TBM), edema and infiltration of inflammatory cells in the interstitium, focal segmental proliferation of glomerular mesangial cells and increase of mesangial matrix, part thickness of interlobular arterial walls. The above abnormalities of other four groups were significantly attenuated compared to model group. Electron microscopy of model group revealed patchy vacuolar changes and fatty degeneration of cells from proximal convoluted tubular epithelium, swelling of mitonchondria, reduce of organelle, karyorrhexis, apoptosis, infiltration of inflammatory cells (phagocytes and lymphocytes) in the interstitium and infiltration of lymphocytes in the epithelium, thickness of interlobular arterial walls, stenosis of lumina. The above abnormalities of electron microscopy in other four groups were remarkably improved compared to model group as well, especially in ligustrazine II group and prednisone group. Conclusions Pathological change of ATN is confirmed in kidney tissue and the rat ATN model induced of AA is successfully established. Benazepril, prednisone and ligustrazine can attenuate the toxic effects by AA. Prednisone and ligustrazine have a better efficacy.

Mesenchymal stem cells express major histocompability complex (MHC)Ⅰin low levels, but do not express MHC Ⅱ, so it has a low immunogenicity. It can block maturity of dendritic cells, depress immune response of T lymphocytes, and also mediate immune suppression by secreting several soluble cytokines. In light of these characters, mesenchymal stem cell can avoid allograft rejection in human and animal transplantation. It has been reported previously that human mesenchymal stem cells cultivated in growing rodent embryos can grew out of new kidney and ureter. Furthermore, urea nitrogen and creatinine levels were significantly higher in liquid collected from the new ureter compared with the animal serum levels, which suggested that the new kidney had generated urine. This native kidney has low immunogenicity, little side-effect after transplantation, extensive sources, so it may have wide space in self-kidney transplantation.

Objective To evaluate the efficacy and safety of immunosuppressive strategy of leflunomide (LEF) combined with calcineurin inhibitor and prednisone in Chinese renal transplant recipients.Methods Prospective clinical study was performed in 16 stable renal transplant recipients treated with calcineurin inhibitor, prednisone and either mycophenolate mofetil (MMF) or azathioprine (Aza), and MMF or Aza was replaced by LEF afterward. The loading dose of LEF was 50 mg/day for 3-5 days, and the maintenance dose was 20 mg/day. Prednisone was maintained 10 mg/day. The doses of CsA were adjusted according to its blood concentration.Results One patient dropped due to economic reason 1 mouth later, and continued to take Aza. Another one patient switched back to MMF due to a slight increase of serum creatinine (from 130 ?mol/L to 143 ?mol/L) 6 months after conversion. The remaining 14 patients were still on LEF. The mean observation time under LEF was (8.7?7.2) months (1～18 month). The mean serum creatinine was (103?24) ?mol/L before conversion, (95?26) ?mol/L at 6th month, and (108?27) ?mol/L at one year post-conversion. There was one episode of biopsy proved reversible acute rejection. The observed side effect was tolerable alopecia in 2 cases and rash in 1 case, but there were no significant increases in liver function, decrease of blood WBC count, deterioration of anemia, or any serious infection in any of the patients.Conclusion Immunosuppressive strategy of LEF+calcineurin inhibitor and prednisone is effective and safe in stable Chinese renal transplant recipients.

Objective To investigate the expression and significance of VEGF and NF-κB/p65 in the two subtypes of pleomorphic adenoma. Methods Immunohistochemistry was applied to detect the expression of VEGF and NF-κB/p65 in pleomorphic adenoma of 60 patients including 31 cases of cell-rich and 29 cases of stroma-rich as well as normal salivary gland tissues of 30 cases from adjacent tumor. Results VEGF positive staining was mainly found in tumor epithelia,while NF-κB/p65 positive was detected in gland alveolus cell and ductal epithelia. The Mean optical density( MA ) values of VEGF were 955.67 ± 305.79,149. 13 ± 60. 85 and 53.46 ± 9. 66, respectively, in cell-rich adenoma, stroma-rich adenoma and normal control. The difference in VEGF expression between the groups was significant (Ps ＜ 0. 05 ) . The MA values of NF-κB/p65 were 529. 80 ± 164. 81,43.40 ±5.46 and 6. 84 ± 1.91 ,respectively,in three groups mentioned above. The difference in NF-κB/p65 expression between the groups was significant ( Ps ＜ 0. 05 ). In pleomorphic adenoma, the expression level of NF-κB/p65 was positively correlated with VEGF. Conclusion ( 1 ) The angiogenesis and proliferation potential of carcinomas increased with the cell component in pleomorphic adenoma. Stroma-poor adenoma is more frequently subjected to malignant transformation than stroma-rich adenoma. (2) NF-κB/p65 may have effects on angiogenesis by activating VEGF. Detecting the expression of VEGF and NF-κB/p65 may be helpful to predict the biological behavior of pleomorphic adenoma and prognosis of the patients, which couldprovide useful information for future targeted therapy of pleomorphic adenoma.

Objective To explore the effect of VEGF-C,VEGFR-3 gene in primary culture in vitro of laryngeal squamous carcinoma tissue by dexamethasone (DEX). Methods Applying the technique of Drimary tissue cuiture in vitro,twelve specimens,which were identified pathologically as laryngeal squamous cell carcinoma,were cultured.After succeeded culture of twelve specimens,the cells were divided in to two groups.One continued to cuhum,another gave 10-7 mol/L of DEX.VEGF-C and VEGFR-3 gene express in 12 cases of cell were examined by reverse transcription polymerase chain reactions(RT-PCR).Results The frequency of VEGF-C(83%) and VEGFR-3(58%) in primary culture in wtro of laryngeal squamous carcinoma tissue were higher than that of the primary culture in vitro of laryngeal squamous carcinoma tissue by dexamethasone (DEX) (25%,8%P＜0.05).Conclusion The expressions of VEGF-C and VEGFR-3 in Drimary culture in vitro of laryngeal squamous carcinoma tissue by DEX are decreased.It may provide guide to apply DEX in clinic laryngeal squamous carcinoma chemotherapy and laryngeal squamous carcinoma laryngeal obstruction.

Objective To observe the effect of different calcium concentration peritoneal dialysate on calcium-phosphorus metabohsm in uremia patients under peritoneal dialysis. Methods Forty uremia patients who the first entered peritoneal dialysis were divided into two groups: standard calcium concentration group (20 cases), low calcium concentration group (20 cases). Treated with continuous ambulatory peritoneal dialysis (CAPD), combining with oral calcium carbonate, observing 12 months. Results When the first entering CAPD, serum calcium, phosphorus, calcium-phosphorus product, immunoreactive parathyroid hormone (iPTH) of the two groups had no differences. Hyperphosphatemia, lower iPTH were universal. After 6 months' treatment, hypercalcemia and hyperphosphatemia in standard calcium concentration group got increasingly serious.While in low calcium concentration group, serum calcium, phosphorus, calcium-phosphorus product all decreased significantly, moreover, they were also lower than post-treatment standard calcium concentration group(P<0.01). In the following 6 months, in low calcium concentration group,serum calcium, calcium-phosphorus product maintained at the normal level serum phosphorus also decreased to the normal level iPTH maintained about 150 ng/L. During the treatment, all patients had no hypotension and hyperspasmia. Conclusion Low calcium concentration peritoneal dialysate can ameliorate disorder of calcium-phosphorus metabohsm, delay the appearance of its comphcations.

Objective To investigate the probable pathologic basis of amido proton transfer(APT) imaging by analysing APT signal intensity and pathologic features of different grades of glioma.Methods Twenty-eight patients with glioma confirmed by postoperative pathology underwent APT scan.All the patients were divided into two groups,including 11 cases in low grade (WHO Ⅰ and Ⅱ) and 17 cases in high grade (WHO Ⅲ and Ⅳ) group.The APT rate of tumor core was measured.The specimens were processed with routine hematoxylin-eosin (HE) staining and immunohistochemistry of Ki-67 and CD34.Independent-samples t test was used to detect the difference of APT rate,cellularity,microvessel density and Ki-67 labeling indices of tumor core between low grade and high grade group.Pearson correlation analysis and multi-variable linear regression analysis were used to detect the relationship of APT rate with cellularity,microvessel density and Ki-67 labeling indices of the tumor core.Results The APT rate,cellularity and proliferation index were (2.3±0.6) ％,(9.4±2.4) ％ and (14.2±5.4) ％ in low grade group,while (3.6±0.7) ％,(18.4±4.7) ％ and (31.7±4.5) ％ in high grade group,respectively.Microvessel density was (19.0±7.4) per high-power field in low grade group and (38.9±11.3) in high grade group.There were statistical differences of the APT rate,cellularity,microvessel density and proliferation index between the low grade group and the high grade group (t=-4.94,-5.89,-5.13,and-9.28,respectively,P＜0.01).The APT rate was positive correlated with cellularity,microvessel density and proliferation index.The coefficient of correlation were 0.904,0.598,and 0.750,respectively,(P＜0.01).Multiple linear correlative analysis showed that increasing cellularity (X1),microvessel density (X2) and proliferation index (X3) were the main factors for increasing APT rate,and the correlation equation was Y=0.801 + 0.12X1-0.003X2 + 0.026X3 (F=46.437,P＜0.01,R2=0.853).Conclusions The APT signal intensity of the tumor core could reflect the pathologic features of glioma.The APT rate was positive correlated with cellularity,microvessel density and proliferation index,which indicate the higher APT rate the higher grade tumor.

Objective CXCR4-overexpressing bone marrow-derived mesenchymal stem cells (CXCR4-BMSC) were constructed and co-cultured with hypoxia/re-oxygenation pretreated renal tubular epithelial cells (HR-RTEC).Repair of HR-RTEC was detected and the possible mechanism was also discussed.Methods CXCR4-BMSC (CXCR4-BMSC/eGFP,eGFP as the tracer gene) and null-BMSC (BMSC/eGFP) were obtained by gene transfection technique,and the level of CXCR4 in the transfected cells was detected.RTEC was cultured under hypoxia/re-oxygenation condition for 12 h,respectively,to obtain HR-RTEC,which was used to simulate AKI in vitro.BMSC and HR-RTEC were co-cultured for 12 h,and the proportion of apoptotic cells among the HR-RTEC was assayed by immunofluorescence technique.Western blot was used to test the protein levels of cleaved Caspase-3 and Bcl-2.The number of migrating BMSC was also assayed.After culturing with the HR-RTEC culture supernatant,the expression of cytokeratin 18 (CK18) in BMSC was tested by immunofluorescence staining.Cytokines including bone morphogenetic protein-7 (BMP-7),hepatic growth factor (HGF) and interleukin-10 (IL-10) in the BMSC culture supernatant were detected by ELISA method.Results Expression of CXCR4 was enhanced in CXCR4-BMSC.Proportions of the apoptotic cells among HR-RTEC after being co-cultured with BMSC,CXCR4-BMSC and null-BMSC were all decreased,especially in the C/H group.The decreased cleaved Caspase-3 and enhanced Bcl-2 were also observed in HR-RTEC.The number of migrating CXCR4-BMSC was the highest.Proportions of CK18+ cells in BMSC,CXCR4-BMSC and null-BMSC were all low and showed no difference.However,CXCR4 overexpression in BMSC stimulated secretions of BMP-7,HGF and IL-10.Conclusions CXCR4-overexpressing BMSC has more repair effect on the co-cultured HR-RTEC,the enhanced migration ability and secretion ability of CXCR4-BMSC are the possible mechanisms.