Injury in organs after cardiopulmonary bypass: a comparative experimental morphological study between a centrifugal and a new pulsatile pump

The aim of this investigation was to assess organ injury provoked by a new pulsatile pump for cardiopulmonary bypass (CPB) with respect to a conventional centrifugal pump. Eight pigs in the pulsatile group (PG) and five in the centrifugal group (CG) underwent a partial CPB lasting 180 min. The animals were sacrificed 180 min after CPB was suspended, and a morphological study of fragments of ventricular wall, liver, lung, and kidney was performed. In CG, centrilobular hepatic necrosis was observed accompanied by sinusoidal dilatation and congestion, multiple focuses of myocardial ischemia, and minor to moderate pulmonary interstitial edema. In PG, diffuse centrilobular sinusoidal congestion in the liver, congestion and capillary dilatation of low intensity in the ventricular wall, and nonsignificant pulmonary interstitial septal edema was observed. In the kidney, both groups showed degenerative changes of the tubular cells and nonsignificant tubular dilatation. These results suggest a better peripheral circulation in the pulsatile group.     

Down-regulation of inducible nitric oxide synthase (iNOS) in rat with congenital hydronephrosis

BACKGROUND: Most of our knowledge concerning obstructive uropathy has been derived mainly from surgically manipulated animal models, and the pathogenesis of congenital obstructive hydronephrosis is not fully elucidated. Nitric oxide (NO) acts as an important biological modulator with diverse physiological functions, which can be either toxic or protective depending on the situation. NO is synthesized from l-arginine by nitric oxide synthase, and in the kidney iNOS is expressed spontaneously. The aim of our study is to investigate the expression of iNOS protein and its relationship with tubulointerstitial fibrosis and tubular cell apoptosis in congenital hydronephrosis. METHODS: We conducted histological studies on 18 kidneys of six-week-old-rats from an inbred colony of congenital hydronephrosis with reference to the histological grading of the affected kidney, tubulointerstitial fibrosis, renal tubular atrophy, and tubular cell apoptosis. Renal transforming growth factor-beta1 (TGF-beta1) level was determined by a sandwich ELISA assay and the expression of iNOS was analyzed by western blotting. RESULTS: Most of the hydronephrotic kidneys were markedly enlarged with dilatation of the collecting system, parenchymal thinning, tubular atrophy, interstitial infiltration and fibrosis. Renal TGF-beta1 level was higher in hydronephrotic kidneys than normal control kidneys (364.81 +/- 52.60 vs. 221.19 +/- 22.53 pg/mg protein, P < 0.05). Tubular apoptotic score in hydronephrotic kidneys was also significantly higher than in the normal control kidneys (1.97 +/- 0.42 vs. 0.14 +/- 0.02/HPF, P < 0.01). The expression of iNOS protein was lower in the affected kidneys compared with the normal control kidneys (8.79 +/- 0.78 vs. 14.00 +/- 0.83 arbitrary unit, P < 0.01). There was a negative correlation between iNOS expression and histological grading in congenital hydronephrosis. The iNOS expression also correlated negatively with renal interstitial fibrosis, TGF-beta1 level and tubular cell apoptosis. CONCLUSION: Our study confirmed the down-regulation of iNOS expression in affected kidneys from rats with congenital hydronephrosis, in which the cytoprotective effect of NO may be lost or weakened.     

Altered expression of immune modulator and structural genes in neonatal unilateral ureteral obstruction

BACKGROUND: Congenital obstructive nephropathy is a condition characterized by hydronephrosis, tubular dilatation, apoptosis, and atrophy, as well as interstitial cellular infiltration and progressive interstitial fibrosis. The renal consequences of chronic unilateral ureteral obstruction (UUO) in the neonatal rat are similar to those of clinical congenital obstructive nephropathy. METHODS: To define alterations in renal gene expression induced by chronic neonatal UUO, Sprague-Dawley rats were subjected to UUO or sham operation within the first 2 days of life, and kidneys were harvested after 12 days. RESULTS: Microarray analysis revealed that the mRNA expression of multiple immune modulators, including krox24, interferon-gamma regulating factor-1 (IRF-1), monocyte chemoattractant protein-1 (MCP-1), interleukin-1beta (IL-1beta), CCAAT/enhancer binding protein (C/EBP), p21, c-fos, c-jun, and pJunB, was significantly increased in obstructed compared to sham-operated kidneys (all P < 0.05). Western blot analysis revealed significant changes in immune modulator protein abundance in the obstructed versus sham-operated kidney for krox24 (P = 0.0004), IRF-1 (P = 0.005), MCP-1 (P = 0.01), and JunD (P = 0.0008). Alternatively, the abundance of all of the immune modulator proteins was similar in sham-operated and obstructed kidneys in rats subjected to acute (4 days) neonatal UUO. Microarray analysis studies also reveal that structural genes that comprise the cytoskeleton and cell matrix are significantly up-regulated by chronic neonatal UUO, including calponin, desmin, dynamin, and lumican (all P < 0.05). CONCLUSION: Multiple genes are aberrantly expressed in the kidney of rats subjected to chronic neonatal UUO. Elucidation of these genes involved in neonatal UUO may lead to new insight about congenital obstructive nephropathy.     

The Effect of Cardiopulmonary Bypass and Hypothermic Circulatory Arrest on Hepatic Histology in Newborn Animals: An Experimental Study

Still little is known about the effect of cardiac surgery on neonatal hepatic tissue. We examined the effect of cardiopulmonary bypass (CPB) and the effect of deep hypothermic circulatory arrest (DHCA) on neonatal hepatic tissue. Liver biopsies of neonatal piglets were taken after CPB (n = 4), after DHCA (n = 5), and after surgery without CPB (non‐CPB; n = 3). Additionally, findings were compared to those of control piglets (n = 9). The liver specimens were fixed, stained with hematoxylin and eosin, and scored regarding inflammatory reaction, hepatocellular edema, and apoptosis. Inflammation score of treated groups was higher than in control; CPB 2.5 ± 0.5, DHCA 1.6 ± 0.4, non‐CPB 1.2 ± 0.6, control 0.4 ± 0.3 (P < 0.001 CPB and DHCA vs. control; P < 0.05 non‐CPB vs. control). Hepatic cell edema was more evident after DHCA (score 2.0 ± 0.4 vs. 0.2 ± 0.3 in control and 0.6 ± 0.5 after CPB; P < 0.001 and P < 0.05, respectively). The highest apoptotic cell count was in the non‐CPB group (22.3 ± 6.3 vs. 11.4 ± 3.6 in control and 8.9 ± 5.4 after CPB; P < 0.05). The present study showed that (i) surgical trauma induces hepatic cell apoptosis; (ii) CPB increases hepatic inflammatory reaction; and (iii) DHCA amplifies hepatic cell edema.     

Increased transforming growth factor-β1 and tubulointerstitial fibrosis in rats with congenital hydronephrosis

OBJECTIVES: Most of our knowledge concerning renal obstruction has been derived from experimental animal models, and it is not yet well defined in spontaneous hydronephrosis. The aim of our study is to evaluate the roles of transforming growth factor-beta1 (TGF-beta1) and apoptosis in congenital hydronephrotic kidneys in comparison with experimental models. METHODS: We made histological studies on kidneys from 6-week-old Wistar-Imamichi rats with congenital unilateral hydronephrosis as well as surgical models of complete or partial unilateral ureteral obstruction. The severity of hydronephrotic kidneys was evaluated on routine hematoxylin and eosin (H&E) stained sections, and the tubulointerstitial fibrosis analyzed morphometrically on Masson's trichrome stained sections. Renal tubular atrophy was assessed on periodic acid Schiff (PAS) stained sections, and tubular cell apoptosis assessed with TUNEL technique. The renal TGF-beta1 level was determined by a sandwich enzyme-linked immunosorbent assay (ELISA). RESULTS: We observed a significant loss of kidney weight with profound compensatory growth of the contralateral kidney in rats with congenital hydronephrosis. Most of the hydronephrotic kidneys were markedly enlarged with dilatation of the collecting system, renal parenchymal thinning, tubular atrophy, interstitial infiltration and fibrosis. The renal TGF-beta1 level was markedly elevated in hydronephrotic kidneys as compared with normal controls (326.01 +/- 30.64 pg/mg protein vs 227.81 +/- 11.07 pg/mg protein, P < 0.01). The tubular apoptotic score in hydronephrotic kidneys was also significantly higher than normal controls (2.17 +/- 0.50/HPF [high power field]vs 0.14 +/- 0.04/HPF, P < 0.01). The increased TGF-beta1 and apoptotic status paralleled the histological changes of tubulointerstitial fibrosis and tubular atrophy. Similar findings were also obtained in experimental obstructive models. CONCLUSION: In comparison with surgical models of partial and complete ureteral obstruction, our data provide solid morphological and molecular evidences of renal obstruction in rats with congenital hydronephrosis.     

Effects of extracorporeal shock waves on renal morphology, renal function and blood pressure in rats--follow-up for one year]

Effects of extracorporeal shock waves on renal tissue, renal function, and blood pressure were studied by applying 500 shock waves to both kidneys in 72 female Wistar rats. Six groups, 12 rats in each, were sacrificed on days, 1, 7 and at months 1, 3, 6 and 12 after the procedure, when serum levels of BUN, creatinine, urine levels of beta 2-microglobulin (beta 2-MG), N-acetyl-beta-D-glucosaminidase (NAG), 28-kDa carbindin-D and creatinine clearance (Ccr) were determined. Findings were then compared with those from the control group. In each group, both kidneys were weighed and histologically evaluated. In the treatment group, systolic blood pressure was measured at post-irradiation months 1, 3, 6, 9, and 12; plasma renin activity was studied 6 and 12 months after irradiation to make evaluation in comparison with the control group. In the treatment group, histologically, coagulative necrosis associated with bleeding around the renal tubules and tubular epithelial cell degeneration were marked on day 1, but the glomerulus was kept in relatively good shape. Inflammatory cellular infiltration and interstitial fibrosis were noted on day 7 and the addition of scar formation 1 month after irradiation. Interstitial fibrosis, inflammatory cellular infiltration, scar formation, and tubular epithelial degeneration remained significant even after 12 months. In the treatment group, kidneys weighed significantly more than in the control group from day 1 through month 3, with edema likely accounting for this. However, weight then significantly declined 12 months after irradiation, owing to suspected scarring atrophy.(ABSTRACT TRUNCATED AT 250 WORDS)     

Histological and ultrastructural evaluation of extracorporeal shock wave lithotripsy-induced acute renal lesions: preliminary report

Biopsy material taken from kidneys of 14 patients with renal stones before performing extracorporeal shock wave lithotripsy (ESWL) and an average of 15 days after was examined histologically and ultrastructurally. In the post-ESWL specimens, light microscopy revealed edema and extravasation of urine and blood into the interstitial spaces, blocking of cortical tubules by hemorrhagic streaks and widespread dilatation of the veins, with signs of endothelial destruction and partial organization of thrombi. By using the electron microscope, abnormalities of the endothelium and glomerular epithelium, hemosiderin accumulations in the tubular cells and small linear patches of fibrosis at the corticomedullary junction and in the cortical interstitial spaces were seen. This preliminary report indicates that renal damage can be shown soon after ESWL on histological and ultrastructural studies and that the lesions observed can be either reversible or permanent.     

Protective effects of cranberries on infection-induced oxidative renal damage in a rabbit model of vesico-ureteric reflux

OBJECTIVE: To evaluate the protective effects of cranberry fruit, which have known antioxidant effects, on infection-induced oxidative renal damage in a rabbit model of vesico-ureteric reflux (VUR). MATERIALS AND METHODS: In all, 36 New Zealand male rabbits were divided into five groups, with a sham operation in four rabbits serving as the control (group 1). To create unilateral VUR the roof of the left intravesical ureter was incised, and VUR confirmed 2 weeks after surgery. In all, 32 rabbits with VUR were divided into four groups; 2, VUR alone (with sterile urine); 3, a group infected with Escherichia coli; 4, with intravesical E. coli instillation but fed cranberries; and 5, intravesical E. coli instillation plus an intraperitoneal injection with melatonin group. At 3 weeks after surgery the rabbits were killed, the kidneys obtained and examined histopathologically to evaluate inflammation, fibrosis and tubular changes. Oxidative renal damage was evaluated by measuring malondialdehyde in the renal tissue. RESULTS: Grossly, the refluxing kidney was larger than the contralateral normal kidney, and the refluxing ureter was dilated and tortuous. Microscopy of tissues from the kidneys in group 3 showed apparent periglomerular mononuclear cell infiltration, tubular dilatation and atrophy, and interstitial fibrosis. The kidneys from groups 2, 4 and 5 showed mild mononuclear cell infiltration with no interstitial fibrosis. The level of malondialdehyde in the kidneys of group 3 was significantly higher than that in group 2, 4 and 5 (P < 0.05); the level in groups 4 and 5 did not differ significantly from that in group 2. CONCLUSIONS: This study shows that cranberries have an anti-inflammatory effect through their antioxidant function and might prevent infection-induced oxidative renal damage. Thus, clinically cranberries might be used as a beneficial adjuvant treatment to prevent damage due to pyelonephritis in children with VUR.     

Effect and mechanism of soluble epoxide hydrolase inhibitor in renal fibrosis mice model

Objective To investigate the effect and mechanism of soluble epoxide hydrolase inhibitor (sEHI) for NF-κB pathway and cell circle arrest of tubular epithelial cell in unilateral ureteral obstruction (UUO) mice model. Methods Thirty-two healthy C57BL/6 male mice performed UUO surgery to induce renal interstitial fibrosis. Animals were randomly divided into 4 groups: sham group (n=8), sEHI (1 mg?kg-1?d-1) group (n=8), UUO group (n=8) and UUO+sEHI (1 mg?kg-1?d-1) group (n=8). Daily sEHI [1-(1-methylsulfonyl-piperidin-4-yl)-3-(4-trifluoromethoxy-phenyl)-urea, TUPS] or 2% DMSO was applied to mice by oral gavage from day 1 to day 14 after surgery. All mice were sacrificed at day 14 and kidneys were harvested for further analysis. The changes of renal tissue morphology and pathology were observed by Hematoxylin and eosin (HE) and sirius red staining. The expressions of sEH, nuclear factor κB p65 (NF-κB p65) and IκB were measured by Western blotting. The expressions of TNF-α, IL-1β, MCP-1, IL-6, TGF-β, CTGF, collagen-IV and α-SMA were analyzed by real-time PCR. Immunofluorescence staining of phospho-histone H3 (p-HH3) and Ki67 was performed to determine the stage of cell cycle G2/M arrest. Results The expression and activity of sEH increased in UUO group (P﹤0.05). Administration of sEHI inhibited activity of sEH and infiltration of inflammatory cell in tubular interstitial, as well as attenuated tubular damage and tubular interstitial fibrosis. Western blotting analysis revealed administration of sEHI inhibited up-regulated NF-κB p65 and down-regulated IκB in UUO group (P﹤0.05). Real-time PCR demonstrated that administration of sEHI obviously decreased the mRNA expression of cytokines and fibrosis markers, including of TNF-α, IL-1β, MCP-1, IL-6, TGF-β, CTGF, Collagen-IV, α-SMA (P﹤0.05). Immunofluorescence staining showed that there were much more p-HH3 and Ki67 double positive nuclear tubular epithelial cells and interstitial cells in UUO group, compared with Sham group (P﹤0.05). Administration of sEHI reduced the number of double positive nuclear cell only in tubular epithelial cells (P﹤0.05), but not in interstitial cells. Conclusions In UUO tubular interstitial fibrosis model, sEHI inhibits the activation of NF-κB pathway by down-regulating p65 and up-regulating IκB and ameliorates the infiltration of inflammatory cells. In addition, sEHI plays anti-fibrosis effect by moderating cell cycle G2/M arrest and reducing the excrete of pro-fibrosis factors of tubular epithelial cells.     

Ureteral obstruction in neonatal mice elicits segment-specific tubular cell responses leading to nephron loss

BACKGROUND: To elucidate the sequence of renal responses leading to nephron loss in obstructive nephropathy, we examined the evolution of segmental nephron cellular changes consequent to chronic unilateral ureteral obstruction (UUO) in the neonatal mouse. METHODS: Neonatal mice were subjected to UUO or sham-operation, and kidneys were harvested 5, 12 or 19 days after surgery. Proximal tubules (PT), distal tubules (DT) and collecting ducts (CD) were identified with lectins. Histomorphometric quantitation was made for cellular necrosis, apoptosis, proliferation, tubular dilatation, tubular basement membrane (TBM) thickening, interstitial collagen, and glomerular maturation. The distribution of hypoxic tissue was determined using pimonidazole as a marker. Additional studies were performed by mechanically stretching monolayer cultures of mouse proximal tubular and collecting duct cells, and measuring apoptosis. RESULTS: Neonatal UUO induced an arrest of glomerular maturation throughout the period of study. Chronic UUO induced hypoxia, tubular necrosis, proliferation, and TBM thickening in the PT, but stimulated apoptosis in the DT and CD. Tubular dilation in the obstructed kidney was most severe in CD and least severe in PT. Tubular cell apoptosis closely paralleled tubular dilation (P < 0.05), and fibrosis surrounding individual tubules also correlated with tubular dilation (P < 0.001). Mechanical stretching of cultured mouse tubular cells induced apoptosis directly proportional to the magnitude of axial strain: apoptosis was consistently greater in CD than in PT cells (P < 0.05). CONCLUSIONS: Following UUO, the co-localization of hypoxia with cellular proliferation, necrosis, and TBM thickening of the PT is consistent with ischemic injury resulting from vasoconstriction. In contrast, a selective dilation of the distal portion of the nephron (DT and CD), which results from the greater tubular compliance there, leads to stretch-induced epithelial cell apoptosis, along with a progressive peritubular fibrosis. Nephron loss in the obstructed developing kidney likely results from complex, segment-specific cellular responses.     

Chronic progressive renal lesions induced by lithium

New Zealand white rabbits, eight fed lithium (Li) (50 to 250 mmole LiCl/kg food) and seven controls (C) had sequential open renal biopsies at zero, one, three, six, and 12 months. A distinctive histological lesion, consisting of cytoplasmic vacuolation and accumulation of glycogen in cells lining distal convoluted tubules and collecting ducts, was present in Li (one, three, six, and 12 months), but was absent in Li prior to lithium (zero months) and in C (zero, one, three, six, and 12 months). Histological changes of chronic focal interstitial nephropathy namely, interstitial fibrosis, (quantitated by point counting), tubular atrophy and cast formation (quantitated by digitization), and glomerular sclerosis (determined as the percent of sclerosed glomeruli) showed significant differences between Li and C from as early as one month (interstitial fibrosis, P less than 0.02; tubular atrophy, P less than 0.05; casts, P less than 0.05), and up to 12 months (glomerular sclerosis, P less than 0.05). Distal tubular dilatation and microcyst formation, (quantitated by digitization) was also marked in Li compared with C from one month (P less than 0.05). The degree of distal tubular dilatation and other changes of interstitial nephropathy tended to progress with duration of lithium exposure. Macroscopically, Li kidneys (12 months) were pale, granular, and exhibited microcysts. Raised blood urea (P less than 0.02) and serum creatinine levels (P less than 0.05) were also late features (12 months) of lithium-induced nephropathy. The data support the view that lithium induces chronic renal lesions. The precise relationship between the distinctive distal tubular lesion, distal tubular dilatation and focal interstitial nephropathy remains speculative.     

Evaluation of contralateral kidney, liver and lung after extracorporeal shock wave lithotripsy in rabbits

An experimental study was carried out to evaluate the effects of extracorporeal shock wave lithotripsy (ESWL) on contralateral kidney, liver and lung by histopathological and biochemical methods. Twelve New Zealand rabbits were allocated to two groups (n = 6). Tissues of control group (CG, n = 6) were harvested without any intervention. In ESWL group (EG), right kidneys were exposed to 3,000 shock waves at 14 kV energy using electro-hydraulic type ESWL device three times every other day. Both kidneys, liver, and right lobe of lung tissues in EG were harvested on seventh day. Kidneys were examined histopathologically for presence of glomerular and tubular injury, interstitial edema, congestion, inflammation and fibrosis. Livers were examined for hepatocyte vacuolization, congestion, portal inflammation and fibrosis. Lung tissues were examined for loss of normal structure, emphysema, interstitial congestion–edema, prominent alveolar septal vessels, interstitial inflammation, intra-alveolar hemorrhage, intraluminal hemorrhage, peribronchial edema, congestion, inflammation in bronchial wall and epithelial desquamation. Biochemical analysis of tissue samples was performed for oxidative injury markers. Histopathological evaluations revealed that tubular injury was found in both shocked and contralateral kidneys (p < 0.05). EG showed higher grades of portal fibrosis in liver and higher grades of peribronchial congestion in lung when compared to CG (p < 0.05). Biochemical evaluations of both kidneys showed that malondialdehyde levels were higher in EG than in CG (p < 0.05). ESWL causes histopathologic alterations both in shocked and contralateral kidneys. Extrarenal tissues such as liver and lung can be affected by shock waves histopathologically and oxidative injury of contralateral kidney may occur acutely after ESWL.     

Expression of adhesion molecules in kidney with experimental chronic obstructive uropathy: the pathogenic role of ICAM-1 and VCAM-1

BACKGROUND: Chronic obstructive uropathy induced by maintained unilateral ureter ligation in the rat is characterized morphologically by interstitial inflammation, interstitial fibrosis, and tubular atrophy. Infiltrating mononuclear inflammatory cells, particularly T lymphocytes and macrophages, may contribute to the progression of this lesion by mediating tubular injury and by the activation of interstitial fibroblasts, with resultant tubular atrophy and interstitial fibrosis, respectively. Altered expression and activation of adhesion molecules by leukocytes, vascular endothelial cells, and parenchymal cells likely contributes both to the infiltration of inflammatory cells into the tubulointerstitial compartment and to the interaction of activated inflammatory cells with parenchymal cells. METHODS: In the current study, we examined changes in the expression of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) in a 90-day model of maintained unilateral ureter ligation in male Sprague-Dawley rats. RESULTS: Rat kidneys showed constitutive expression of ICAM-1 mRNA and constitutive immunostaining for ICAM-1 in peritubular capillaries, glomeruli, and a small percentage of cortical tubules. Ureter ligation resulted in a rapid increase in ICAM-1 mRNA, which was almost 2-fold greater than those of the contralateral and control kidneys as early as 3 h and which was maintained at a 4- to 6-fold higher level in the ligated vs. contralateral kidneys throughout the entire 90-day time course. There was a marked increase in ICAM-1 immunostaining within the tubular epithelium, with up to 80% of both cortical and medullary tubular cross-sections showing strong apical immunostaining from day 6 to 25, with a subsequent decrease throughout the remainder of the experiment. ICAM-1 immunostaining in the expanding interstitium in the ligated kidneys showed a gradual increase throughout the duration of the experiment. In contrast, glomerular immunostaining for ICAM-1 was decreased in the ligated compared to the contralateral kidneys throughout the entire experiment. There was a later but prominent increase in VCAM-1 mRNA in ligated kidneys, which was first evident at 2 days and which was maintained 2- to 10-fold greater than the contralateral kidneys throughout the entire time course. VCAM-1 immunostaining increased in the expanding interstitium, but decreased in glomeruli in obstructed vs. contralateral kidneys. Tubular staining for VCAM-1 did not change after ureter ligation. CONCLUSION: Increased ICAM-1 and VCAM-1 may contribute to the prominent inflammatory cell infiltration in the chronic tubulointerstitial nephritis accompanying maintained unilateral ligation. Tubule expression of ICAM-1, which occurs during a similar time course as previously documented for tubular cell proliferation and especially tubular cell apoptosis in this model, may contribute to injurious interactions of activated inflammatory cells with tubular epithelium.     

阻断B7诱导大鼠心脏移植免疫耐受的实验研究

目的　研究阻断B7方法诱导大鼠心脏异位移植的免疫耐受。　方法　采用Ono法建立大鼠异位心脏移植模型 ,实验组腹腔注射B7阻断剂CTLA 4Ig,观察大鼠移植的心脏存活天数 ,病理改变和术后IL 2 ,IgG以及IgM含量的变化。　结果　实验组移植的心脏存活时间为 :(31 6 0± 1 82 )d ,对照组 (7 2 5± 0 71)d ,差异有显著性意义 (P <0 0 1)。组织学改变 :实验组见局灶性血管周围或间质内淋巴细胞浸润和局灶性心肌损伤 ,病理分级Ⅰ～Ⅱ级。对照组可见大量淋巴细胞浸润 ,心肌细胞损伤和坏死 ,间质内出血水肿 ,病理分级Ⅳ级。术后IL 2含量实验组比对照组明显下降 ,有显著性差异 ,P <0 0 1。IgG和IgM含量差异无显著性意义 (P >0 0 5 )。　结论　阻断B7能诱导大鼠心脏移植免疫耐受 ,为移植排斥反应提供了新的治疗方法     

Expression of MHC class I-related Chain B (MICB) molecules on renal transplant biopsies

BACKGROUND: MICA and MICB (MHC class I-related chain A and B) are polymorphic genes that encode molecules related to MHC class I and are expressed on epithelial cells in response to stress. Incompatible donor MIC antigens can stimulate antibody production in transplant recipients. This study was designed to determine MICB expression in kidney pretransplant and any subsequent changes in expression following transplantation and to correlate changes with inflammatory markers and clinical events. METHODS: Paired renal biopsies obtained from living donor (n=10) and cadaveric allografts (n=50) before and 7 days posttransplant were stained for MICB, leukocytic infiltration, and HLA class II antigens. RESULTS: Variable tubular MICB expression was evident in donor biopsies [high 6/60 (10%), low/negative 13/60 (22%), intermediate 41/60 (68%)]. Following transplantation, MICB was up-regulated on renal tubules of 17/60 (28%) biopsies and was associated with MHC class II antigen induction (P=0.02) and leukocyte infiltration (P=0.01). Acute tubular necrosis leading to delayed graft function (DGF) and acute rejection (AR) cause cellular stress within the transplanted kidney. We found a strong association between up-regulation of MICB and cellular stress, 15/17 biopsies with up-regulated MICB expression had AR and/or DGF (P=0.003). CONCLUSIONS: This is the first study demonstrating variable levels of MICB expression in kidneys before transplantation and induction of MICB expression following renal transplantation. MICB expression is associated with HLA class II antigen induction, leukocytic infiltration of the graft and cellular stress in the transplanted kidney. Expression of MICB could contribute significantly to the alloimmune response in mismatched donors and recipients.     

Electron microscopic study of acute retrograde pyelonephritis in mice

A strain of Escherichia coli O6:H-, which was isolated from a patient with acute pyelonephritis, was used to produce ascending pyelonephritis in mice. The histologic features at the early stage of acute pyelonephritis and the pathways of bacterial invasion and distribution in the infected kidneys were studied by using transmission electron microscope. The histologic changes were characterized by degeneration and destruction of renal pelvic and tubular epithelial cells, and a massive infiltration of polymorphonuclear leukocytes. Bacteria invaded the pelvic surface and spread over the renal medulla and cortex by contiguity twelve hours after infection. It was also shown that bacteria ascended the tubules, multiplied in the tubular lumina, destroyed the tubular epithelial cells, and spread over the renal cortex by twelve hours. In addition, bacteria and leukocytes phagocytizing bacteria were present in the capillaries in the renal interstitium twelve hours after infection.     

Renal remodelling in dietary protein modified rat polycystic kidney disease

Dietary protein restriction slows progression of the Han:SPRD-cy rat model of polycystic kidney disease. We undertook studies to examine the relative changes in interstitial and tubular pathology as a result of feeding an 8% casein (LP) diet to Han:SPRD-cy rats. Archival tissue from a previous study comparing LP and 20% casein (NP) diets was examined morphometrically after immunohistochemical or histochemical staining for apoptosis, proliferation antigens, interstitial fibrosis, and macrophage infiltration. Expression of common extracellular matrix genes was measured by Northern analysis. Animals fed LP diet demonstrated reduced tubular epithelial remodelling compared with animals fed NP diet by both proliferating cell nuclear antigen-positive cells (57.5 vs. 71.6 cells/mm epithelium, P=0.007) or apoptosis (31.2 vs. 35.6 cells/mm epithelium, P=0.006). Interstitial pathology demonstrated that LP feeding was associated with proportionately greater reductions in interstitial fibrosis (0.3 vs. 1.3 ml/kg body weight, P=0.003), interstitial cellularity (361 vs. 604 cells/high-power field, P=0.0002), and interstitial macrophages (67 vs. 149 cells/high-power field, P=0.0002). Northern analysis only revealed significantly lower levels of monocyte chemoattractant protein mRNA (P=0.04) in animals fed the LP diet. Dietary protein restriction modifies both tubule and interstitium, with significant impact upon interstitial inflammation and fibrosis in the Han:SPRD-cy rat. Received: 24 April 1998 / Revised: 10 November 1998 / Accepted: 11 November 1998     

A case of Chinese herbs–induced renal interstitial fibrosis associated with fibrosis of salivary glands

We report a case with interstitial nephropathy induced by Chinese herbs that was accompanied by lesions in the minor salivery glands. A 61-year-old man had taken Chinese herbs since 1989 to “promote health.” Mouth dryness started around April 1996, and he was hospitalized in December because of kidney dysfunction. On admission, serum urea nitrogen was 20 mg/dL; serum creatinine, 2.5 mg/dL; serum uric acid, 2.5 mg/dL; serum phosphate, 1.6 mg/dL; and urinary β2-microglobulin, 67,468 μg/d. In addition, general aminoaciduria, renal glucosuria, and proximal tubular acidosis were noted, and he was diagnosed as having Fanconi syndrome. Kidney biopsy showed thickening and doubling of the glomerular basement membrane. Cell infiltration was scarce in the interstitium, with destruction of tubules and severe interstitial edema and fibrosis. Lip biopsy performed because of significant thirst showed atrophy and fibrosis of the minor salivary glands with poor cell infiltration. Most of the symptoms were improved after discontinuation of Chinese herbs. This case shows the possibility that Chinese herbs might have caused tissue damage characterized by fibrosis, not only in the kidneys, but also in the salivary glands.     

Obstructive uropathy in the mouse: role of osteopontin in interstitial fibrosis and apoptosis.

BACKGROUND: Osteopontin is a macrophage adhesive protein that is expressed by renal tubules in tubulointerstitial disease. METHODS: To investigate the function of OPN, we induced tubulointerstitial disease in OPN null mutant (OPN-/-) and wild-type (OPN+/+) mice by unilateral ureteral ligation. Tissue was analyzed for macrophages (ED-1), types I and IV collagen deposition, TGF-beta expression, and for tubular and interstitial cell apoptosis. RESULTS: Obstructed kidneys from both OPN-/- and OPN+/+ mice developed hydronephrosis, tubular atrophy, interstitial inflammation and fibrosis. OPN was absent in OPN-/- kidneys but was increased in obstructed OPN+/+ kidneys. Macrophage influx, measured by computer-assisted quantitative immunostaining, was less in OPN-/- mice compared to OPN+/+ mice at day 4 (threefold, P < 0.02), day 7 (fivefold, P < 0.02), but not at day 14. Interstitial deposition of types I and IV collagen were also two- to fourfold less in obstructed OPN-/- kidneys (P < 0.02). There was also a reduction of TGF-beta mRNA expression in the interstitium at day 7 (by in situ hybridization) and a near significant 34% reduction in cortical TGF-beta activity (P = 0.06) compared to obstructed OPN+/+ kidneys at day 14. Obstructed kidneys from OPN-/- mice also had more interstitial and tubular apoptotic cells (TUNEL assay) compared to obstructed OPN+/+ mice at all time points. The ability of OPN to act as a cell survival factor was also documented by showing that the apoptosis of serum-starved NRK52E renal epithelial cells was markedly enhanced in the presence of neutralizing anti-OPN antibody. CONCLUSION: OPN mediates early interstitial macrophage influx and interstitial fibrosis in unilateral ureteral obstruction. OPN may also function as a survival factor for renal tubulointerstitial cells.     

成人微小病变肾病综合征发生急性肾损伤的相关影响因素分析

目的探讨成人微小病变肾病综合征发生急性肾损伤( AKI)的相关影响因素。 方法回顾性分析2002年1月1日至2015年12月31日在解放军总医院病理诊断为微小病变肾病,临床表现为首发肾病综合征的成年患者。记录其横断面临床及病理指标,并将其分为AKI组及非AKI组进行比较。用单因素及多元Logistic回归分析与AKI发生相关的影响因素。并对AKI相关的各影响因素进行交互作用检验。 结果共纳入403例患者,男女比例为1∶1.13,肾活检时平均年龄为(39.5 ± 15.1)岁,其中118(29.3%)例发生了AKI。AKI组与非AKI组相比,年龄、性别、尿蛋白定量、血清白蛋白、血肌酐、血尿素氮、估算的肾小球率过滤、肾小管萎缩、肾间质病变差异均有统计学意义(P<0.05)。单因素Logistic回归分析显示高龄、男性、尿蛋白定量多、肾小管萎缩、肾间质水肿、间质纤维化及炎细胞浸润、高血压是成人微小病变肾病发生AKI的危险因素。交互作用检验表明血清白蛋白对AKI的作用受到肾间质纤维化的显著影响(P＝0.0 050),且在调整年龄分组、性别、高血压、尿蛋白定量、肾小管萎缩、肾间质水肿、肾间质炎细胞浸润混杂因素后,其交互作用仍显著(P＝0.0 263)。从多元Logistic回归分析可见,在无肾间质纤维化的人群中,血清白蛋白水平的升高是AKI的独立保护因素(调整后的OR 0.8,95%CI 0.7～ 0.9,P<0.001)。在有肾间质纤维化人群中,血清白蛋白的升高对AKI肾脏的保护作用不显著(调整后的OR 1.0,95%CI 0.9～1.0,P＝0.0 278)。 结论高龄、男性、尿蛋白定量多、肾小管萎缩、肾间质水肿、间质纤维化及炎细胞浸润、高血压是成人微小病变肾病综合征发生AKI的危险因素。血清白蛋白升高对AKI的保护作用受到肾间质纤维化的影响。