The abnormal expressions of tristetraprolin and vascular endothelial growth factor family which participate in ultrafiltration failure

Objective To observe the expression of tristetraprolin (TTP) and vascular endothelial growth factor (VEGF) family, to test and verify whether lymphangiogenesis was involved in the occurrence of ultrafiltration failure (UFF) as well as angiogenesis. Methods Forty male SD rats of clean grade were selected (180-200 g). These rats were divided into five groups randomly: normal group (n=8), sham operation group (n=8), uremia group (n=8), peritoneal dialysis (PD) 2-week group (n=8), PD 4-week group (n=8). The uremic rats model was established by 5/6 nephrectomy, and of which the PD rats model was established on the basis. The rats of PD2-week group and PD4-week group were given regular PD with 4.25% peritoneal dialysis fluid in dose of 3 ml/100 g body weight. PD2-week group received peritoneal dialysis for 2 weeks, PD4-week group for 4 weeks. Before the rats were sacrificed, peritoneal equilibration test (PET) was applied to calculate the mass transfer of glucose and peritoneal ultrafiltration volume. The protein expressions of VEGF, VEGF–C in each group of rats’ parietal peritoneum were detected by immunohistochemical staining. Microvessel density (MVD) and lymphatic vessel density (LVD) of peritoneal tissue were marked and quantified with anti-CD31 antibody, anti-LYVE-1 antibody. RT-PCR was applied to detect the mRNA expressions of VEGF-A, VEGF-B, VEGF-C, VEGF-D, TTP. Western blotting was used to detect the protein expression of TTP. Results (1)PET revealed that, compared with normal group, the mass transport of glucose and the peritoneal ultrafiltration volume of both PD 2-week group and PD 4-week group elevated (P＜0.05); and compared with PD 2-week group, PD 4-week group’s elevated (P＜0.05). (2) Compared with normal group, the protein expression of CD31, LYVE-1, the count of MVD and LVD were increased in uremia group and PD4-week group (P＜0.05). Those of PD4-week groups likewise were increased compared to uremia group (P＜0.05). (3) Compared with normal group, the mRNA expressions of VEGF, VEGF-A, VEGF-B, VEGF-C, VEGF-D were significantly increased in uremia group (P＜0.05); Compared with uremia group, the expressions in PD4-week group were significantly increased (P＜0.05). Compared with normal group, the mRNA and protein expressions of VEGF, VEGF-C were increased in PD 2-week group (P＜0.05); Compared with PD 2-week group, the expressions were increased in PD 4-week group (P＜0.05). (4) Compared with normal group, the expressions of TTP protein was decreased in uremia group and PD 2-week group (P＜0.05). Compared with uremia and PD2-week group, the expressions of TTP protein was significantly decreased in PD4-week group (P＜0.05). Conclusions High glucose peritoneal dialysis fluid and uremic circumstance result in the expression changes of TTP and VEGF family in a PD time-dependent manner. High glucose peritoneal dialysis liquid gives rise to angiogenesis and lymphangiogenesis, both of which lead to UFF.     

Effects of cyclooxygenase - 2 inhibitor on peritoneal function and angiogenesis in uremic peritoneal dialysis rats

Objective To investigate the effects of the cyclooxygenase-2 (COX-2) inhibitor (celecoxib) on angiogenesis and peritoneal function of uremic peritoneal dialysis rats. Methods Forty - eight male SD rats were selected, and they were randomly divided into five groups: normal control group(n=8), sham operation group(n=8), uremia group(5/6 nephrectomy, n=8), PD group [4.25% PD solution, 2 weeks PD model(n=8) and 4 weeks PD model(n=8)], PD + celecoxib intervention group[treated by celecoxib(20 mg/kg) via oral gavage, n=8].The peritoneum of uremic peritoneal dialysis rats was observed in different dialysis time from peritoneal structures, functions, peritoneal tissue capillary density (microvessel density, MVD) and COX-2, vascular endothelial growth factor (VEGF) expression level, and the impacts of celecoxib on uremic peritoneal dialysis rats peritoneal angiogenesis and peritoneal function were study. Results With the conduct of the peritoneal dialysis, peritoneal thickness increased, the inflammatory cells infiltrated, peritoneal equilibration test (PET) showed that ultrafiltration volume decreased significantly (P＜0.05), the amount of glucose transport rate rised significantly (P＜0.05), but the celecoxib could improve net ultrafiltration volume (P＜0.05), and reduce the glucose transport rate (P＜0.05). The peritoneal tissue MVD and COX - 2, VEGF expression were significantly increased in uremia group and PD group compared with that in the normal control group (all P＜0.05), were significantly lower in PD + Celecoxib intervention group than that in uremia group (P＜0.05). The correlation analysis showed that the level of COX-2 protein expression with MVD, VEGF protein expression was positively correlated (both P＜0.05), the level of VEGF protein expression and MVD was positively correlated (P＜0.05). Conclusions In vivo high glucose dialysate and uremia environmental can stimulate the COX-2 and VEGF expression raised, and the capillaries production increased in peritoneal tissue. Celecoxib can alleviate the change of peritoneal tissue morphology and function in long-term peritoneal dialysis rats. Celecoxib inhibits the peritoneal neovascularization of uremic peritoneal dialysis rats, possibly through inhibition of COX-2 expression to reduce the production of VEGF.     

Pharmacological inhibition of heparin-binding EGF-like growth factor promotes peritoneal angiogenesis in a peritoneal dialysis rat model

Background

Molecular mechanisms of peritoneal dialysis (PD) ultrafiltration failure, peritoneal neo-angiogenesis, and fibrosis remain to be determined. We aimed to determine the role of heparin-binding EGF-like growth factor (HB-EGF) inhibition on angiogenesis of peritoneal membrane in a PD rat model.

Methods

32 male Wistar rats were assigned into (1) control group; (2) uremic non-PD group: subtotal nephrectomy-induced uremic rats without PD; (3) uremic rats subjected to PD: uremic rats that were dialyzed with Dianeal^® for 4 weeks; (4) CRM 197 group: dialyzed uremic rats were supplemented with CRM197, a specific HB-EGF inhibitor. Peritoneal transport function was examined by peritoneal equilibration test. Expression of HB-EGF and EGFR in peritoneal samples were examined by real-time PCR, immunohistochemical staining, and western blot.

Results

Progressive angiogenesis and fibrosis were observed in uremic PD rats, and there were associated with decreased net ultrafiltration (nUF), increased permeability of peritoneal membrane, and reduced expression of HB-EGF and EGFR protein and mRNA in uremic PD rats compared to uremic non-PD or control groups (both p < 0.05). CRM197 significantly induced peritoneal membrane permeability, decreased nUF, increased higher vessel density, and reduced pericyte count compared to that of uremic PD rats. The levels of HB-EGF and EGFR expression negatively correlated with vessel density in peritoneal membrane (both p < 0.001).

Conclusion

PD therapy was associated with peritoneal angiogenesis, functional deterioration, and downregulation of HB-EGF/EGFR. Pharmacological inhibition of HB-EGF promoted PD-induced peritoneal angiogenesis and fibrosis and ultrafiltration decline, suggesting that HB-EGF downregulation contributes to peritoneal functional deterioration in the uremic PD rat model.

     

乳腺癌组织中COX-2、VEGF-C表达与淋巴转移的相关性研究

目的 探讨COX-2、VEGF-C在人乳腺癌组织中的表达及其与淋巴转移之间的关系.方法 运用免疫组织化学SABC法检测COX-2和VEGF-C在乳腺癌组织中的表达情况.结果 60例乳腺癌组织中COX-2和VEGF-C的表达阳性率分别为66.7%和60.0%,且二者表达呈正相关(r=0.429,P<0.05).COX-2阳性、VEGF-C阳性组淋巴转移的发生率(80.0%)明显高于COX-2阴性、VEGF-C阴性组(21.4%;P<0.05).结论 COX-2、VEGF-C在乳腺癌组织中呈过表达,呈正相关关系,且与乳腺癌的淋巴转移关系密切,COX-2表达上调可能促使VEGF-C的过表达,诱导肿瘤淋巴管的生成,从而导致乳腺癌细胞淋巴转移的发生.     

TGF-β1 Promotes Lymphangiogenesis during Peritoneal Fibrosis

Peritoneal fibrosis (PF) causes ultrafiltration failure (UFF) and is a complicating factor in long-term peritoneal dialysis. Lymphatic reabsorption also may contribute to UFF, but little is known about lymphangiogenesis in patients with UFF and peritonitis. We studied the role of the lymphangiogenesis mediator vascular endothelial growth factor-C (VEGF-C) in human dialysate effluents, peritoneal tissues, and peritoneal mesothelial cells (HPMCs). Dialysate VEGF-C concentration correlated positively with the dialysate-to-plasma ratio of creatinine (D/P Cr) and the dialysate TGF-β1 concentration. Peritoneal tissue from patients with UFF expressed higher levels of VEGF-C, lymphatic endothelial hyaluronan receptor-1 (LYVE-1), and podoplanin mRNA and contained more lymphatic vessels than tissue from patients without UFF. Furthermore, mesothelial cell and macrophage expression of VEGF-C increased in the peritoneal membranes of patients with UFF and peritonitis. In cultured mesothelial cells, TGF-β1 upregulated the expression of VEGF-C mRNA and protein, and this upregulation was suppressed by a TGF-β type I receptor (TGFβR-I) inhibitor. TGF-β1–induced upregulation of VEGF-C mRNA expression in cultured HPMCs correlated with the D/P Cr of the patient from whom the HPMCs were derived (P<0.001). Moreover, treatment with a TGFβR-I inhibitor suppressed the enhanced lymphangiogenesis and VEGF-C expression associated with fibrosis in a rat model of PF. These results suggest that lymphangiogenesis associates with fibrosis through the TGF-β–VEGF-C pathway.The decrease in ultrafiltration capacity that is associated with the high peritoneal solute transport that is observed after prolonged peritoneal dialysis (PD) treatment is a major reason for its discontinuation.^1–4 Several studies have shown that a higher peritoneal solute transport rate is associated with reduced survival of PD patients.^1,2,5 The characteristic features of chronic peritoneal damage in PD treatment are associated with submesothelial fibrosis and neoangiogenesis.^6,7 Analyses of the surface peritoneum showed no significant changes in vessel density with duration of PD.^6,8 In addition, the vessel density in patients with ultrafiltration failure (UFF) was significantly higher than the vessel density in normal individuals or non-PD patients, but it was not higher than the vessel density in patients undergoing PD.⁶ These findings suggest that factors other than increased vascular density may be involved in disease states associated with increased transport of peritoneal membranes. In addition, the relationship between peritoneal fibrosis and UFF remains obscure.Blood capillaries have a continuous basal lamina with tight interendothelial junctions and are supported by pericytes and smooth muscle cells. In contrast, lymphatic capillaries are thin-walled with a wide lumen and do not contain pericytes or basement membrane. The structures of lymphatic vessels are suitable for the removal of tissue fluid, cells, and macromolecules from the interstitium.^9–11 If lymphangiogenesis develops in the peritoneal membrane, absorption of the PD fluid could be increased and lead to UFF. An increase in the number of lymphatic vessels has recently been reported in several disease conditions, including tumor metastasis,^12–15 chronic respiratory inflammatory diseases,^16–18 wound healing,¹⁹ and renal transplant rejection.^20,21 We recently reported that lymphangiogenesis had developed in tubulointerstitial fibrosis of human renal biopsy specimens,²² and we also reported the mechanisms of lymphangiogenesis in rat unilateral ureteral obstruction models.²³The lymphatic absorption rate, which is measured by the rate at which intraperitoneally administered radioactive serum albumin or macromolecule dextran 70 disappears, is significantly higher in patients with UFF, and lymphatic reabsorption is considered to be one of the causes of UFF.^24–27 However, the results from these clinical approaches have been controversial.^28,29 In addition, little is known about the pathology and the process of lymphangiogenesis in patients with UFF and peritonitis.In this study, we investigated lymphangiogenesis and the expression of vascular endothelial growth factor-C (VEGF-C), which is a potentially important mediator of lymphangiogenesis, in human peritoneal tissues, PD effluent, and peritoneal mesothelial cells. We also explored VEGF-C induction by TGF-β1 in the human mesothelial cell line (Met-5A) and cultured human peritoneal mesothelial cells (HPMCs) from the spent PD effluent of patients with varying rates of peritoneal transport. Finally, we explored the relationship between peritoneal fibrosis and lymphangiogenesis in rats that were administered chlorhexidine gluconate (CG) into the abdominal cavity, which provides a model of chemically induced peritoneal inflammation/fibrosis.^30–32 This work is the first report to show that lymphangiogenesis is linked to the peritoneal fibrosis that is often associated with a high peritoneal transport rate.     

Peritoneal morphologic changes in a peritoneal dialysis rat model correlate with angiopoietin/Tie-2

The angiopoietin/Tie-2 system plays an important role in the initiation of angiogenesis. However, the role of angiopoietin/Tie-2 in peritoneal angiogenesis and fibrosis is unclear. In our study we investigated the peritoneal morphologic changes in a uremic peritoneal dialysis (PD) rat model, focusing on the relationship between angiopoietin/Tie-2 and peritoneal angiogenesis. We subjected uremic (subtotal nephrectomy) rats to dialysis, using a standard PD solution, for 10 days, 28 days, or 56 days, and compared them with uremic rats that had not undergone dialysis and control rats. Functional [dialysate-to-plasma (D/P) creatinine; ultrafiltration (UF)] and structural (vessel density and thickness of the submesothelial extracellular matrix) changes of the peritoneum were quantified. Levels of angiopoietin (Ang)-1, Ang-2, Tie-2 and vascular endothelial growth factor (VEGF) were examined in the peritoneum by real-time quantitative polymerase chain reaction (PCR) and related to angiogenesis. The uremic group that had not undergone dialysis was characterized by increased vessel density in the peritoneum compared with that of the control, which correlated with decreased UF and increased D/P creatinine. Progressive angiogenesis and fibrosis were found in the PD groups when compared with the uremic non-dialyzed or control group, accompanied by an increased D/P creatinine that occurred in the PD group after 56 days, while UF decreased. Furthermore, Ang-2 and VEGF levels increased, while Tie-2 level decreased significantly in the uremic non-dialyzed group compare with the control. This tendency was more obvious in the PD groups than in the uremic non-dialyzed or control group, but no difference was found among the PD groups. Both VEGF and Ang-2 correlated positively with vessel density, while Tie-2 correlated negatively. We confirmed angiogenesis and fibrosis changes of the peritoneum as a result of uremic status and PD therapy in the uremic PD rat model. An increased level of Ang-2 and a reduced level of Tie-2 in conditions of uremia and PD therapy correlated with peritoneal angiogenesis and functional deterioration.     

Effect of rosiglitazone on the expression of AQP-1, VEGF-A and COX-2 in uremic rat of peritoneal dialysis

Objective To investigate the effect of rosiglitazone(RGZ) on peritoneal morphology, function and the expressions of Aquaporin 1 (AQP-1), vascular endothelial growth factor A(VEGF-A) and cyclooxygenase 2(COX-2) in uremic rat of peritoneal dialysis. Methods Thirty Sprague-Dawley rats were randomly divided into five groups. Group S (n=6) was subjected to sham operation. Group N (n=6) was subjected to nephrectomy with silicon catheter inserted, but no peritoneal exposure. Group P (n=6) was subjected to nephrectomy with silicon catheter inserted and receiving daily peritoneal injection through the catheter, using 4.25% peritoneal dialysis fluid 10 ml twice a day for 2 weeks. Group R (n=6) was subjected to nephrectomy with silicon catheter inserted and receiving daily peritoneal injection through the catheter, using 4.25% peritoneal dialysis fluid containing rosiglitazone (0.2 mg/kg) 10 ml twice a day for 2 weeks. Group GW (n=6) was subjected to nephrectomy with silicon catheter inserted and receiving daily peritoneal injection through the catheter, using 4.25% peritoneal dialysis fluid containing rosiglitazone (0.2 mg/kg) and GW9662 (0.2 mg/kg) 10 ml twice a day for 2 weeks. After two weeks of dialysis, a 90 min peritoneal equilibration test was performed and the amount of ultrafiltration was accurately measured. The partial peritoneum tissues of rats were harvested and stained by hematoxylin-eosin (HE), then morphology changes of partial peritoneum were examined by light microscopy. The expression of AQP-1,VEGF-A and COX-2 in omentum were detected with immunohistochemistry assay. AQP-1, VEGF-A and COX-2 mRNA were detected by qRT-PCR. Results Morphology changes of partial peritoneum showed that compared with Group S,a dramatic increase in thickness of the mesothelium-to-muscle layer of peritoneum in Group N, P, R and GW(P＜0.05). Compared with group P, the thickness significantly decreased in Group R(P＜0.05). PET results showed that compared with Group S, ultrafiltration (UF) significantly reduced in Group P, R, and GW(P＜0.05). Compared with Group P, ultrafiltration significantly increased in Group P, R, and GW (P＜0.05). Compared with group S, the expressions of AQP1, VEGF-A and COX-2 mRNA and protein were significantly increased in group P, R and GW(P＜0.05). Compared with group P, the expressions of AQP1, VEGF-A mRNA and protein were significantly decreased in Group R and GW(P＜0.05). Compared with group P, the expressions of COX-2 mRNA and protein were significantly decreased in group R (P＜0.05), while no differences in the expression of COX-2 mRNA and protein in group GW (P＜0.05). Conclusions Rosiglitazone can inhibit peritoneal interstitial and vascular proliferation, protect peritoneal function and increase ultrafiltration. Rosiglitazone can protect peritoneal function probably by inhibiting expression of VEGF-A and COX-2.     

可溶性Tie2融合蛋白对尿毒症腹膜透析大鼠血管新生的影响

目的 观察可溶性Tie2融合蛋白(sTie2/Fc)对尿毒症腹膜透析大鼠腹膜血管新生的影响.方法 48只雄性SD大鼠,按随机数字表法分为以下6组:正常对照组、假手术组、尿毒症非腹透组、4.25％腹透组、sTie2/Fc 2.5 μg/kg干预组、sTie2/Fc 5.0 μg/kg干预组.腹透组按照4.25％腹透液30...     

检测微淋巴管及其密度和血管内皮生长因子C对结直肠癌的临床意义

目的探讨检测微淋巴管、微淋巴管密度(LMVD)和血管内皮生长因子C(VEGF-C)的表达对结直肠癌的临床意义。方法应用5′-核苷酸酶(5′-Nase)组织化学、SABC免疫组织化学(免疫组化)和RT-PCR检测80例结直肠癌组织和癌旁组织及30例结直肠正常组织的微淋巴管、LMVD和VEGF-C的表达,并随访、记录患者的临床病理参数和生存资料,分析其相关性。结果(1)结直肠癌、癌旁、正常结直肠组织的微淋巴管均被染成棕黄褐色。结直肠癌组织微淋巴管管腔封闭或无腔,为无功能淋巴管；癌旁组织微淋巴管丰富,管腔大,为功能性淋巴管。(2)癌旁组织LMVD为9．76±2．85,明显高于结直肠正常组织的5．49±．43(t=8．220,P＜0．01)；也高于癌组织的2．13±0．96(t= 15．118,P＜0．001)。(3)结直肠癌VEGF-C蛋白表达阳性率(48．8%)和相对表达量(1．09±1．20)明显高于正常结直肠组织(0和0),与VEGF-C mRNA表达一致；且VEGF-C表达与LMVD相关。(4) LMVD、VEGF-C表达与结直肠癌患者的年龄、性别、肿瘤部位大小、大体组织学类型无关(均P＞0．05)；与Dukes分期(P＜0．0001、P=0．0234)、淋巴结转移(P＜0．0001、P=0．0059)和生存期(P＜0．0001、P＜0．0001)密切相关。LMVD还与分化程度(P=0．0168)和肝肺血行转移(P=0．0088)相关。结论结直肠癌癌旁微淋巴管为功能性淋巴管；癌旁的功能性微淋巴管和增高的LMVD及肿瘤VEGF-C表达,可作为结直肠癌淋巴管生成的形态学特征、分子表型和判断结直肠癌患者淋巴转移及预后的重要指标。     

The Clinical Outcome of End-Stage Renal Disease Patients Who Return to Peritoneal Dialysis After Renal Allograft Failure

Background

With the increased numbers of kidney transplantations, more patients return to dialysis after graft loss (DAGL). The aim of this study was to investigate the safety and efficacy of peritoneal dialysis (PD) after graft loss compared with transplant-naive PD patients (TN-PD).

Method

This study was conducted on 715 patients who started PD between 1988 and 2009, including 47 who started PD after allograft loss (DAGL-PD) and 668 in the (TN-PD) group.

Result

The mean ages were 40.8 ± 10.7 in DAGL-PD group and 51.03 ± 14.20 in TN-PD group (P < .01). The most common cause of end-stage renal disease in DAGL was primary glomerulonephritis (76.6%), but it was diabetes mellitus (38.9%) in the TN-PD group (P < .05). Patient survival rates at 1, 5, and 10 years were not different: 100%, 86%, and 57% versus 91%, 70%, and 62%, respectively. PD survival rate at 1, 5, and 10 years did not show significant differences: 98%, 95%, and 88% versus 95%, 80%, and 66%, respectively. The most common causes of death in both groups were infection (DAGL, 26.7%; TN-PD, 24.5%) followed by cardiovascular disease (DAGL, 20.0%; TN-PD, 19.6%); the distribution of causes did not differ significantly (P > .05).

Conclusion

The clinical outcomes of PD in DAGL group were comparable with those of TN-PD patients. Therefore, PD could be considered as a dialysis modality for patients who experience allograft failure.     

Biomolecular markers and involution of hemangiomas

Background/purpose

Vascular anomalies are a diverse set of lesions with distinct clinical behaviors, whose biomolecular characteristics are largely undefined. Common hemangiomas proliferate during the first year of life, then involute at a variable pace over several years. Other vascular tumors may involute much more quickly (rapidly involuting congenital hemangiomas [RICH]), not at all (lymphatic malformation), or display malignant behavior (angiosarcoma). Key cytokines driving angiogenesis include vascular endothelial growth factor (VEGF) family members/receptors (placental growth factor [PIGF], VEGF-A, and VEGF-C) and angiopoietins. The authors hypothesized that involuting hemangiomas would display biologic markers distinctly different from noninvoluting vascular lesions.

Methods

Six patient samples were analyzed: (1) RICH, (2) proliferating hemangioma, (3) involuting hemangioma, (4) tufted angioma, (5) hepatic angiosarcoma, and (6) lymphatic malformation. Detailed examination of endothelial/vascular mural cell status was performed by fluorescent double-label immunostaining using specific markers (PECAM-1, αSMA) in combination with markers of proliferation (anti-phospho-histone H3) or apoptosis (TUNEL). Expression of PIGF, VEGF-A, VEGF-C, and Ang-1 was localized by in situ hybridization.

Results

Involuting/proliferating common hemangiomas demonstrated vasculature with abundant vascular mural cells (αSMA+); in contrast, αSMA(+) cells were rare in RICH vessels. Endothelial apoptosis was increased dramatically, but proliferation was unchanged during involution. VEGF-A was expressed in all lesions except lymphatic malformation, which displayed VEGF-C and Ang-1 upregulation. Strikingly, PIGF expression was increased markedly in the lesions predicted to involute/actively involuting but was virtually absent from noninvoluting tumors.

Conclusions

Vessel architecture and endothelial/vascular mural cell status differed between lesions, differentiating even common versus rapidly involuting hemangioma and corresponded to clinical involution. VEGF-A expression characterized endothelial-derived lesions, whereas VEGF-C marked lymphatic-derived cells. PIGF expression occurred only in vascular anomalies predicted to involute or actively involuting, a pattern potentially linked to PIGF function as a conditional antagonist of VEGF-A. Thus, distinct patterns of morphology and angiogenic factor expression characterize vascular anomalies with different clinical behaviors.     

L-alpha-glycerylphosphorylcholine reduces the microcirculatory dysfunction and nicotinamide adenine dinucleotide phosphate-oxidase type 4 induction after partial hepatic ischemia in rats

Background

We set out to investigate the microcirculatory consequences of hepatic ischemia–reperfusion (IR) injury and the effects of L-alpha-glycerylphosphorylcholine (GPC), a deacylated phospholipid derivative, on postischemic hepatocellular damage, with special emphasis on the expression of nicotinamide adenine dinucleotide phosphate oxidase type 4 (NOX4), which is predominantly expressed in hepatic microvessels.

Materials and methods

Anesthetized male Sprague–Dawley rats were subjected to 60-min ischemia of the left liver lobes and 180-min reperfusion, with or without GPC treatment (50 mg/kg intravenously 5 min before reperfusion, n = 6 each). A third group (n = 6) served as saline-treated control. Noninvasive online examination of the hepatic microcirculation was performed hourly by means of modified spectrometry. Plasma tumor necrosis factor (TNF-α), high-mobility group box 1 protein (HMGB1), plasma aspartate aminotransferase, alanine aminotransferase and lactate dehydrogenase levels, tissue xanthine oxidoreductase (XOR) and myeloperoxidase (MPO) activities, and expressions of NOX2 and NOX4 proteins were determined.

Results

Liver IR resulted in significant increases in NOX2 and NOX4 expressions and XOR and MPO activities, and approximately 2-fold increases in the levels of the inflammatory cytokines TNF-α and HMGB1. The microvascular blood flow and tissue oxygen saturation decreased by ∼20% from control values. GPC administration ameliorated the postischemic microcirculatory deterioration and reduced the liver necroenzyme levels significantly; the NOX4 expression, MPO activity, and HMGB1 level were also decreased, whereas the NOX2 expression, TNF-α level, and XOR activity were not influenced by GPC pretreatment.

Conclusions

NOX4 activation is a decisive component in the IR-induced microcirculatory dysfunction. Exogenous GPC ameliorates the inflammatory activation, and preserves the postischemic microvascular perfusion and liver functions, these effects being associated with a reduced hepatic expression of NOX4.     

Aberrant expression of decoy receptor 3 in human breast cancer: relevance to lymphangiogenesis

Background

Decoy receptor 3 (DcR3), a decoy receptor against Fas ligand belonging to the tumor necrosis factor receptor superfamily, is overexpressed in some forms of cancer. It was recently reported that DcR3 could protect endothelial cells from apoptosis, implying a potential role in the development of vessels, whereas its role in the lymphangiogenesis remains unclear. In the present study, we studied the DcR3 expression and its relationship with the lymphatic microvessel density (LMVD) to investigate if it played a role in the lymph metastasis of human breast cancer.

Materials and methods

Real-time polymerase chain reaction and immunohistochemistry were performed to measure the messenger RNA and protein expression of DcR3 in the breast cancer tissues, noncancerous counterparts, and axillary lymph node from 63 patients. LMVD in these specimens was assessed by counting the D2-40 labeled–microvessels. Furthermore, the correlations between DcR3 expression and LMVD and other clinicopathologic parameters were analyzed.

Results

DcR3 was overexpressed in the breast cancer tissue of 58 patients (92.1%) and was also expressed in vascular endothelial cells and tumor cells in the lymph nodes. LMVD in cancer tissue and lymph nodes were both positively correlated to the aberrant expression of DcR3.

Conclusions

The relevance between DcR3 overexpression and LMVD revealed the existence of possible links between DcR3 and lymphangiogenesis. Based on these findings, it is important to further explore the regulation of lymphangiogenesis operated by the reverse tumor necrosis factor signaling of DcR3.     

Distributions of Angiogenesis and Lymphangiogenesis in Gastrointestinal Intramucosal Tumors

Background Although angiogenesis and lymphangiogenesis in gastrointestinal cancers has been investigated in many studies, their distribution characteristics in gastrointestinal intramucosal tumors have not been well addressed. Methods We evaluated the blood microvessel density (BMVD) and lymphatic microvessel density (LMVD) by immunostaining with monoclonal antibodies of CD34 and D2-40 in 37 patients with stomach intramucosal carcinoma and 28 patients with colorectal intramucosal neoplasia. Microvessels with endothelial cells labeled by CD34 but not by D2-40 were recognized as blood microvessels; and microvessels with endothelial cells labeled by both CD34 and D2-40 were recognized as lymphatic vessels. Furthermore, the relationships between expression of vascular endothelial growth factor (VEGF), VEGF-C, and BMVD, LMVD were investigated as well. Results The LMVD was significantly higher in peritumoral tissues than in corresponding normal tissues in gastrointestinal intramucosal tumors (20.87 versus 14.56, P = 0.003). However, there was no significant difference in the BMVD between peritumoral tissues and corresponding normal tissues (P = 0.166). The BMVD in peritumoral tissues was higher in patients with lymph node metastases than in patients without lymph nodes metastases (P = 0.047). Our results did not show significant association between VEGF, VEGF-C and BMVD, LMVD. Conclusions Our results suggested that the increase of lymphangiogenesis seems superior to the increase of angiogenesis in gastrointestinal intramucosal tumors.     

The cellular contribution to effluent potassium and its relation to free water transport during peritoneal dialysis.

BACKGROUND: Aquaporin-1 (AQP-1) dysfunction is one of the valid theories for decreased free water transport (FWT) in long-term peritoneal dialysis (PD) ultrafiltration failure (UFF). We questioned whether apoptosis of peritoneal cells could be reflected in an increased release of cellular (CR) K(+) and explain AQP-1 dysfunction. If so, negative relationships between CR-K(+) and FWT would be expected. Therefore, we analysed CR-K(+) to total peritoneal K(+) removal, for possible relationships with FWT, the duration of PD, the presence of late UFF and effluent cancer antigen (CA) 125. METHODS: Standard peritoneal permeability analyses done with 3.86% glucose were investigated cross-sectionally in three extreme groups: group I: 19 patients <1 year on PD; group II: 20 patients >4 years on PD without UFF; group III: 19 patients >4 years on PD with UFF. RESULTS: Group III had the lowest values of FWT and CR-K(+) (P < 0.01). CR-K(+) had a positive correlation with FWT in groups I and II, but not in group III. These correlations were also present using much simpler methodologies: replacement of CR-K(+) by mass transfer area coefficient (MTAC)-K(+)/MTAC-creatinine ratio or dialysate over plasma (D/P)-K(+)/D/P-creatinine ratio and replacement of FWT by Na(+)-sieving. No relationship with CA125 was present. CONCLUSIONS: This study shows that other than diffusive and convectional, K(+) transport is not excluded in patients treated with conventional glucose-based PD solutions. We found evidence for release of K(+) from cells. In general, CR-K(+) was related to parameters of FWT, except for long-term patients with UFF. This suggests glucose-induced hypertonic cell shrinkage as a basic physiological phenomenon during PD. The absence of this relationship in long-term PD patients with UFF either suggests a reduction or inhibition of K(+)-channels and may be due to another mechanism than AQP-1 dysfunction. Most likely, CR-K(+) in UFF does not reflect apoptosis. However, the D/P-K(+)/D/P-creatinine ratio may be useful in detecting peritoneal changes.     

Analysis of fluid transport pathways and their determinants in peritoneal dialysis patients with ultrafiltration failure

Ultrafiltration failure (UFF) is a serious complication of peritoneal dialysis (PD). The aim of the study was to analyze changes in water transport and their determinants in UFF patients over the time on PD. Standard peritoneal permeability analyses of 50 stable PD patients with UFF were analyzed. Fluid transport through small pores (SPT), free water transport (FWT) at 60 min, their contributions on total ultrafiltration (SPTC and FWTC), and their determinants were assessed. Patients were divided in Group I (UFF) treated for less than 24 months, Group II treated 24-60 months, and Group III treated for more than 60 months. Group I (UFF) was compared with Group I (non-UFF) matched for the duration of PD treatment and age. Transcapillary ultrafiltration (TCUF), SPT, FWT, and FWTC were significantly lower in Group III when compared to the other UFF groups. In this group also, negative relationship was present between FWT, the ultrafiltration coefficient LpA, and osmotic conductance to glucose on one hand and PD duration on the other. FWT was positively related to osmotic conductance to glucose in all groups. Group I (UFF) showed significantly higher solute transport, effective lymphatic absorption rate, lower TCUF, and lower FWT than Group I (non-UFF). The patterns of UFF in PD patients are dependent on the duration of treatment.     

Preoperative cholangitis during biliary drainage increases the incidence of postoperative severe complications after pancreaticoduodenectomy

Background

It remains controversial how preoperative biliary drainage affects occurrence of severe complications after pancreaticoduodenectomy (PD).

Methods

One hundred twenty-seven patients (60 external drainage and 67 internal drainage) required biliary drainage before PD were retrospectively reviewed.

Results

Preoperative cholangitis in internal drainage group (22.4%) occurred significantly more often than in external drainage group (1.7%; P < .001). The incidence of severe complications (grade III or more) was significantly higher in patients with cholangitis (62.5%) than in those without it (25.2%; P = .002). The incidence of delayed gastric emptying was significantly higher in patients with cholangitis (31.2%) than in those without it (5.4%; P = .001). A multivariate logistic regression analysis revealed that preoperative cholangitis (odds ratio 4.61, 95% confidence interval 1.3 to 16.5; P = .019) was the independent risk factor for severe complications after PD.

Conclusions

Preoperative cholangitis during biliary drainage significantly increases incidence of severe complications after PD.     

Dynamic Toll-like receptor expression predicts outcome of sclerotherapy for lymphatic malformations with OK-432 in children

Background

Sclerotherapy with OK-432 is recommended as a first-line treatment for lymphatic malformations. However, 40% of patients show poor response, defined by involution to <50% of the original size. It has been suggested that the OK-432 effect is highly dependent on the Toll-like receptor (TLR) 4–dependent expression of TLR7 in antigen-presenting cells. We hypothesized that the ability for TLR expression in monocytes after treatment with the TLR4-ligand lipopolysaccharide (LPS) can be used to predict successful OK-432 treatment.

Methods

Blood was taken from children with low responder (LR, n = 6) and high responder (HR, n = 5) of previous OK-432 treatment. Monocytes were stimulated with LPS for 20 h. TLR expression was analyzed with fluorescence-activated cell sorting (mean fluorescence intensity). The level of significance was P ≤ 0.05.

Results

The mean age of patients in the HR group was 1.4 ± 0.9 y and in the LR group 2.8 ± 2.9 y (P = 0.31). The mean TLR4 upregulation after LPS stimulation in the HR group was significantly higher than in the LR group (factor 3.6 versus factor 1 compared with nonstimulated controls; P = 0.037). The mean TLR7 expression did not show significant differences between the groups.

Conclusions

Dynamic TLR4 expression represents most probably a predictive parameter for the treatment of lymphatic malformations with OK-432 and should be further investigated.     

Effect of systemic celecoxib on human meningioma after intracranial transplantation into nude mice

Background

Meningiomas are mostly benign, but they may have a notorious tendency to recur when total resection is not possible. Systemic chemotherapeutical treatment has been largely disappointing. The treatment of meningiomas with the cyclooxygenase-2 (COX-2) inhibitor celecoxib showed inhibitory-growth effects in vitro and in vivo after subcutaneous transplantation into mouse. So far, celecoxib has never been tested in an orthotopic model of meningioma. In this work, we tested the effects of celecoxib on the growth of human benign meningiomas after transplantation into the prefrontal cortex of nude mice after confirming the inhibitory in vitro effect on these cells.

Methods

Primary cell cultures were stereotactically implanted into mice and were treated with 0, 750, or 1,500 ppm celecoxib for 3 months. The mice were then killed and blood was analyzed for celecoxib concentration. The mice brains were histologically processed for measurement of tumor volume, COX-2 expression, proliferation index (PI), intratumoral microvessel density (iMVD), and vascular endothelial growth factor (VEGF) expression.

Results

Treatment with celecoxib had no effect on tumor volume, despite the fact that we found a dose-dependent inhibitory effect on cell cultures and there was a sufficiently high celecoxib concentration in blood plasma and brain tissue. Additionally, celecoxib had neither an effect on COX-2 and VEGF expression nor on the PI and iMVD.

Conclusions

Our findings suggest that celecoxib may not be effective on meningioma growth in clinical settings. In general, these results may indicate that the effect of treatment on brain tumors should not only be tested in a heterotopic environment but also in the orthotopic location of these tumors.     

Triple-layer duct-to-mucosa pancreaticojejunostomy with resection of jejunal serosa decreased pancreatic fistula after pancreaticoduodenectomy

Background

Pancreatic fistula (PF) is one of the most common complications after pancreaticoduodenectomy (PD). We described a new method of pancreaticojejunostomy (PJ) developed by combining triple-layer duct-to-mucosa PJ with resection of jejunal serosa, which was named as modified layer-to-layer PJ (MLLPJ). The aim of the present study was to observe whether the new technique would effectively reduce the PF rate in comparison with two-layer duct-to-mucosa PJ (TLPJ).

Methods

Data on 184 consecutive patients who underwent the two methods of PJ after standard PD between January 1, 2010 and January 31, 2013 were collected retrospectively from a prospective database. The primary endpoint was the PF rate. The risk factors of PF were investigated by using univariate and multivariate analyses.

Results

A total of 88 patients received TLPJ and 96 underwent MLLPJ. Rate of PF for the entire cohort was 8.2%. There were 11 fistulas (12.5%) in the TLPJ group and four fistulas (4.2%) in the MLLPJ group (P = 0.039). Body mass index, pancreatic texture, pancreatic duct diameter, and methods of PJ anastomosis had significant effects on the formation of PF on univariate analysis. Multivariate analysis showed that pancreatic duct diameter ≤3 mm and TLPJ were the significant risk factors of PF.

Conclusions

MLLPJ effectively reduces the PF rate after PD in comparison with TLPJ. Results confirm increased PF rates in patients with pancreatic duct diameter ≤3 mm compared with pancreatic duct diameter >3 mm.