Knockdown of clusterin sensitizes pancreatic cancer cells to gemcitabine chemotherapy by ERK1/2 inactivation. Yong Tang,Fenghua Liu,Chunning Zheng,Shaochuan Sun,Yingsheng Jiang Journal of experimental & clinical cancer research : CR
31
2011
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ABSTRACT: | | 22967941
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Impact of hepatic arterial reconstruction on orthotopic liver transplantation in the rat. Tomohide Hori,Lindsay B Gardner,Florence Chen,Ann-Marie T Baine,Toshiyuki Hata,Shinji Uemoto,Justin H Nguyen Journal of investigative surgery : the official journal of the Academy of Surgical Research
25
2011
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Orthotopic liver transplantation (OLT) models in rats have been investigated in many studies, but detailed information on the impact of hepatic artery (HA) reconstruction on postoperative factors remains to be investigated. HA reconstruction also requires advanced skills. The effect of the reconstruction of the HA by a hand-suture technique in rats with a whole-liver syngeneic graft was investigated. Long-term survival, histopathological assessment, immunohistological evaluation, and blood biochemistry were investigated until postoperative day (POD) 28. From the early postoperative period, significant differences between OLTs with or without HA reconstruction were found in graft parenchymal damage, induction of apoptosis, and transaminase levels, though survival curves and the coagulation profile showed no differences. In OLT without HA reconstruction, biliary proliferation was decreased at POD 5-14, and total bilirubin level was increased at PODs 10 and 14. The study indicates that HA reconstruction is required for reliable OLT in rats. | | 22571774
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Pten deletion causes mTorc1-dependent ectopic neuroblast differentiation without causing uniform migration defects. Guo Zhu,Lionel M L Chow,Ildar T Bayazitov,Yiai Tong,Richard J Gilbertson,Stanislav S Zakharenko,David J Solecki,Suzanne J Baker Development (Cambridge, England)
139
2011
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Neuronal precursors, generated throughout life in the subventricular zone, migrate through the rostral migratory stream to the olfactory bulb where they differentiate into interneurons. We found that the PI3K-Akt-mTorc1 pathway is selectively inactivated in migrating neuroblasts in the subventricular zone and rostral migratory stream, and activated when these cells reach the olfactory bulb. Postnatal deletion of Pten caused aberrant activation of the PI3K-Akt-mTorc1 pathway and an enlarged subventricular zone and rostral migratory stream. This expansion was caused by premature termination of migration and differentiation of neuroblasts and was rescued by inhibition of mTorc1. This phenotype is reminiscent of lamination defects caused by Pten deletion in developing brain that were previously described as defective migration. However, live imaging in acute slices showed that Pten deletion did not cause a uniform defect in the mechanics of directional neuroblast migration. Instead, a subpopulation of Pten-null neuroblasts showed minimal movement and altered morphology associated with differentiation, whereas the remainder showed unimpeded directional migration towards the olfactory bulb. Therefore, migration defects of Pten-null neurons might be secondary to ectopic differentiation. | | 22874917
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Extract of white button mushroom affects skin healing and angiogenesis. W P Lam,C M Wang,T Y Tsui,M S Wai,H C Tang,Y W Wong,L H Lam,L K Hui,D T Yew Microscopy research and technique
75
2011
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White button mushroom extract was examined in this study on (1) its potential effect on angiogenesis in chorioallantoic culture and (2) its recovering effect on the skin after injury in the ICR mice. Methods used included TUNEL assay on apoptosis, immunohistochemistry for vascular endothelial growth factor (VEGF), proliferative cell nuclear antigen (PCNA), epidermal growth factor (EGF), transforming growth factor β (TGF-β), and immune factor CD4 and western blotting. The results of chorioallantoic culture showed that the mushroom treatment led to significant increase in densities of VEGF sites. In the skin injury, ICR mice model increased EGF, PCNA, and collagen fibers, along with decrease of TUNEL positive apoptotic cells and limited reaction of TGF-β and CD4 indicated that white button mushroom extract appeared to have beneficial effects on skin in regeneration and after injury. Microsc. Res. Tech. 2012. | | 22581761
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Hepatic arterial reconstruction for orthotopic liver transplantation in the rat. Tomohide Hori,Lindsay B Gardner,Feng Chen,Ann-Marie T Baine,Toshiyuki Hata,Aimee R Herdt,Shinji Uemoto,Christopher B Eckman,Justin H Nguyen The Journal of surgical research
178
2011
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Orthotopic liver transplantation (OLT) models in rats have been investigated in many studies. The reconstruction of hepatic artery is required for reliable OLT and also requires advanced skills. | | 22591919
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Hepatitis B virus alters the antioxidant system in transgenic mice and sensitizes hepatocytes to Fas signaling. Wang, Q; Na, B; Ou, JH; Pulliam, L; Yen, TS PloS one
7
e36818
2011
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Hepatitis B virus (HBV) is a major etiological factor of hepatocellular carcinoma (HCC). However, the precise pathogenetic mechanisms linking HBV infection and HCC remain uncertain. It has been reported that decreased antioxidant enzyme activities are associated with severe liver injury and hepatocarcinogenesis in mouse models. It is unclear if HBV can interfere with the activities of antioxidant enzymes. We established a HBV transgenic mouse line, which spontaneously developed HCC at 2 years of age. We studied the activities of the antioxidant enzymes in the liver of the HBV transgenic mice. Our results showed that the antioxidant enzymes glutathione peroxidase and superoxide dismutase 2 were down-regulated in HBV transgenic mice and correlated with JNK activation. HBV enhanced the Fas-mediated activation of caspase 6, caspase 8 and JNK without enhancing the activation of caspase 3 and hepatocellular apoptosis. As a proper redox balance is important for maintaining cellular homeostasis, these effects of HBV on the host antioxidant system and Fas-signaling may play an important role in HBV-induced hepatocarcinogenesis. | Western Blotting | 22606292
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Nanoporous peptide particles for encapsulating and releasing neurotrophic factors in an animal model of neurodegeneration. Justin Tan,Yajun Wang,Xiaopei Yip,Fergal Glynn,Robert K Shepherd,Frank Caruso Advanced materials (Deerfield Beach, Fla.)
24
2011
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Neurotrophin-BDNF can be effectively encapsulated in nanoporous poly(L-glutamic acid) particles prepared via mesoporous silica templating. The loaded BDNF can be released in a sustained manner with retained biological activity. Animal experiments demonstrate the released BDNF can efficiently rescue the auditory neurons (as indicated by the arrows) in the cochlea of guinea pigs with sensorineural hearing loss. | | 22610659
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Molecular mechanism of remodeling of autologous artery graft interposed to vein in rabbit. Yanling Feng,Yanguo Shen,Hongqi Zhang Anatomical record (Hoboken, N.J. : 2007)
295
2011
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Our previous study found that the artery interposed to vein did not develop atherosclerosis but rather underwent atrophic remodeling in hyperlipidemic rabbits, suggesting that local hemodynamic load was another important determinant for the development of atherosclerosis. This study focused on the cellular and molecular changes in autologous artery grafts derived from rabbits fed with high lipid diet for 1, 2, 4, 8, and 12 weeks. Thickness, area of vessel wall, and lumen area were measured and analyzed on the grafted common carotid artery (GCCA) interposed to vein and on the right common carotid artery. Apoptosis was detected by terminal deoxynucleotidyl transferase-mediated dUTP nick-end-labeling. Both elastin and collagen of GCCA were identified by the method of double stains of elastin and collagen. Reverse transcription polymerase chain reaction was used to observe matrix metalloproteinases (MMPs) mRNA expression changes in the examined arteries. The lumen area increased gradually in control common carotid artery and remained unchanged in GCCA 3 months later, since the surgery and the start of high lipid diet, while significantly increased apoptosis was evidenced from inner to outer part of GCCA. Collagen content decreased gradually and elastic fibers remained unchanged in GCCA. At 1 week after operation, the mRNA expression of MMP(2) and MMP(9) increased significantly and returned to baseline thereafter. The artery interposed to a vein underwent atrophy, characterized by increased apoptosis in the vessel wall from intima to adventitia, possibly due to low shear stress circumference and reduced vessel collagen resulting from postsurgical upregulated MMP(2) and MMP(9) expression. | | 22213534
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Severity of doxorubicin-induced small intestinal mucositis is regulated by the TLR-2 and TLR-9 pathways. Agnieszka Kaczmarek,Brigitta M Brinkman,Liesbeth Heyndrickx,Peter Vandenabeele,Dmitri V Krysko The Journal of pathology
226
2011
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Intestinal mucositis is a serious complication of cancer chemotherapy and radiotherapy; it frequently compromises treatment and dramatically reduces the quality of life of patients. Different approaches to limit the damage to the intestine during anti-cancer therapy have been largely ineffective due to insufficient knowledge of the mechanism of mucositis development. This study aimed to define the role of TLR-2 and TLR-9 in the modulation of small intestinal damage in a model of doxorubicin-induced mucositis. Doxorubicin-induced intestinal damage was verified by a histological score (HS), analysis of leukocyte influx into the lamina propria, and determination of the number of apoptotic cells. Additionally, the activation status of glycogen synthase kinase 3? (GSK-3?) was assessed. Wild-type (WT) mice injected with doxorubicin demonstrated severe intestinal damage (HS 8.0 ± 0.81), reduction of villus length to 43.9% ± 13.7% of original length, and increased influx of leukocytes as compared to vehicle-injected mice (HS 1.33 ± 1.15). The protective effect of TLR-2 or TLR-9 deficiency was associated with a significant decrease of the HS as compared to WT mice. In the ileum, a minor reduction of villus length and a decreased number of infiltrating leukocytes and TUNEL-positive cells was observed. We demonstrate that the TLR-9 antagonist ODN2088 reduces doxorubicin-induced intestinal damage. Furthermore, we show that GSK-3? activity is inhibited in the absence of TLR-2. The protective capacity of GSK-3? suppression was observed in WT mice by inhibiting it with the specific inhibitor SB216763. Overall, our findings demonstrate that the TLR-2/GSK-3? and TLR-9 signalling pathways play a central role in the development of intestinal mucositis and we suggest a new therapeutic strategy for limiting doxorubicin-induced intestinal inflammation. Copyright © 2011 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. | | 21960132
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Subacute oral toxicity investigation of nanoparticulate and ionic silver in rats. Niels Hadrup,Katrin Loeschner,Anders Bergström,Andrea Wilcks,Xueyun Gao,Ulla Vogel,Henrik L Frandsen,Erik H Larsen,Henrik R Lam,Alicja Mortensen Archives of toxicology
86
2011
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Subacute toxicity of 14 nm nanoparticulate silver (Ag-NP) stabilised with polyvinylpyrrolidone and ionic silver in the form of silver acetate (Ag-acetate) was investigated in four-week-old Wistar rats. Animals received orally by gavage the following: vehicle control (10 ♀, 6 ♂); Ag-NP at doses: 2.25 (8 ♀), 4.5 (8 ♀) or 9 mg/kg bw/day (10 ♀, 6 ♂); or Ag-acetate 9 mg silver/kg bw/day (8 ♀) for 28 days. Clinical, haematolological and biochemical parameters, organ weights, macro- and microscopic pathological changes were investigated. Caecal bacterial phyla and their silver resistance genes were quantified. For the Ag-NP groups, no toxicological effects were recorded. For Ag-acetate, lower body weight gain (day 4-7, 11-14, 14-16, P < 0.05; overall, day 1-28, P < 0.01), increased plasma alkaline phosphatase (P < 0.05), decreased plasma urea (P < 0.05) and lower absolute (P < 0.01) and relative (P < 0.05) thymus weight were recorded. In conclusion, these findings indicate toxicity of 9 mg/kg bw/day ionic silver but not of an equimolar Ag-NP dose. This is in accordance with previously reported data showing that oral Ag-acetate, in comparison with an equimolar dose of Ag-NP, resulted in higher silver plasma and organ concentrations. | | 21969074
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