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71.
Benjamin Namdarian Edwin Wong Ryan Galea John Pedersen Xiaowen Chin Robert Speirs Patrick O. Humbert Anthony J. Costello Niall M. Corcoran Christopher M. Hovens 《Urologic oncology》2013,31(5):649-655
ObjectivesEpithelial-mesenchymal transition (EMT) is known to play an important role in the development of tumor invasion and progression in tumors of epithelial origin. Our aim was to investigate the role of tight junction proteins, Par3/Par6/atypical protein kinase C (APKC), Discs large (Dlg), and Scribble in human bladder pathogenesis.MethodsWe evaluated levels of APKC, Dlg, and Scribble in 92 superficial bladder tumors using tissue microarrays and immunohistochemistry, and correlated expression with pathologic variables and clinical outcomes.ResultsThere was a slight apparent enrichment in strong vs. weak staining for APKC (54.9% vs. 45.1%), Dlg (65.7% vs. 34.3%), and a marked enrichment for Scribble (75% vs. 25%) in the superficial bladder tumors. Univariate analysis determined that both tumor focality and APKC expression were significantly associated with tumor recurrence (P < 0.05). Multivariate analysis using the Cox's proportional hazards model revealed that only APKC (P = 0.025) as well as tumor focality (P = 0.018) were independent and significant prognostic factors for tumor recurrence in all patients. We found that no immunohistochemical staining of any of the cell polarity proteins significantly predicted for tumor progression on either univariate or multivariate analysis.ConclusionsLoss of APKC expression in superficial bladder tumors is a strong predictor of tumor recurrence. 相似文献
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April Saval PA 《The journal of spinal cord medicine》2013,36(4):394-397
Background/Objective: Intrathecal baclofen (ITB) has been shown to be an effective treatment for severe spasticity of spinal or cerebral origin. Although most patients respond well to an ITB trial, there are often difficulties in achieving and/or maintaining such effectiveness with ITB pump treatment. There are few published guidelines for dosing efficacy and no studies looking at the effect of concentration of ITB on spasticity management.Methods: Case series of 3 adults with severe spasticity treated with ITB pump: a 44-year-old man with C7 tetraplegia using a 40-mL Medtronic SynchroMed II pump with 500-μg/mL concentration; a 35-year-old woman with traumatic brain injury with right spastic hemiplegia using a 18-mL Medtronic SynchroMed EL pump with 2,000-μg/mL concentration; and a 43-year-old woman with spastic diplegic cerebral palsy using a 40-mL Medtronic SynchroMed II pump with 2,000-μg/mL concentration.Results: After reducing ITB concentrations in the pump, either as part of a standard protocol for dye study to assess the integrity of pump and catheter system or secondary to plateau in therapeutic efficacy, patients experienced temporary, significant reduction in spasticity based on range of motion, Modified Ashworth scores, and verbal feedback.Conclusions: Decreasing the concentration of ITB seems to affect spasticity control. Further research in this area is needed for those patients with refractory spasticity to optimize efficacy of ITB therapy. 相似文献
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Maria B. Goncalves Earl Clarke Carl Hobbs Tony Malmqvist Robert Deacon Julian Jack Jonathan P. T. Corcoran 《The European journal of neuroscience》2013,37(7):1182-1192
The retinoic acid receptor (RAR) α system plays a key role in the adult brain, participating in the homeostatic control of synaptic plasticity, essential for memory function. Here we show that RARα signalling is down‐regulated by amyloid beta (Aβ), which inhibits the synthesis of the endogenous ligand, retinoic acid (RA). This results in the counteraction of a variety of RARα‐activated pathways that are key in the aetiopathology of Alzheimer's disease (AD) but which can be reversed by an RARα agonist. RARα signalling improves cognition in the Tg2576 mice, it has an anti‐inflammatory effect and promotes Aβ clearance by increasing insulin degrading enzyme and neprilysin activity in both microglia and neurons. In addition, RARα signalling prevents tau phosphorylation. Therefore, stimulation of the RARα signalling pathway using a synthetic agonist, by both clearing Aβ and counteracting some of its toxic effects, offers therapeutic potential for the treatment of AD. 相似文献
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SJ Smith CV Rahman PA Clarke AA Ritchie TW Gould JH Ward KM Shakesheff RG Grundy R Rahman 《Annals of the Royal College of Surgeons of England》2014,96(7):495-501
Introduction
The median survival of patients with glioblastoma multiforme (astrocytoma grade 4) remains less than 18 months despite radical surgery, radiotherapy and systemic chemotherapy. Surgical implantation of chemotherapy eluting wafers into the resection cavity has been shown to improve length of survival but the current licensed therapy has several drawbacks. This paper investigates in vivo efficacy of a novel drug eluting paste in glioblastoma.Methods
Poly(lactic-co-glycolic acid)/poly(ethylene glycol) (PLGA/PEG) self-sintering paste was loaded with the chemotherapeutic agent etoposide and delivered surgically into partially resected tumours in a flank murine glioblastoma xenograft model.Results
Surgical delivery of the paste was successful and practical, with no toxicity or surgical morbidity to the animals. The paste was retained in the tumour cavity, and preliminary results suggest a useful antitumour and antiangiogenic effect, particularly at higher doses. Bioluminescent imaging was not affected significantly by the presence of the paste in the tumour.Conclusions
Chemotherapy loaded PLGA/PEG paste seems to be a promising technology capable of delivering active drugs into partially resected tumours. The preliminary results of this study suggest efficacy with no toxicity and will lead to larger scale efficacy studies in orthotopic glioblastoma models. 相似文献78.
Neuropeptide Y Attenuates Stress‐Induced Bone Loss Through Suppression of Noradrenaline Circuits 下载免费PDF全文
PA Baldock S Lin L Zhang T Karl Y Shi F Driessler A Zengin B Hörmer NJ Lee IPL Wong EJD Lin RF Enriquez B Stehrer MJ During E Yulyaningsih S Zolotukhin ST Ruohonen E Savontaus A Sainsbury H Herzog 《Journal of bone and mineral research》2014,29(10):2238-2249
Chronic stress and depression have adverse consequences on many organ systems, including the skeleton, but the mechanisms underlying stress‐induced bone loss remain unclear. Here we demonstrate that neuropeptide Y (NPY), centrally and peripherally, plays a critical role in protecting against stress‐induced bone loss. Mice lacking the anxiolytic factor NPY exhibit more anxious behavior and elevated corticosterone levels. Additionally, following a 6‐week restraint, or cold‐stress protocol, Npy‐null mice exhibit three‐fold greater bone loss compared to wild‐type mice, owing to suppression of osteoblast activity. This stress‐protective NPY pathway acts specifically through Y2 receptors. Centrally, Y2 receptors suppress corticotropin‐releasing factor expression and inhibit activation of noradrenergic neurons in the paraventricular nucleus. In the periphery, they act to control noradrenaline release from sympathetic neurons. Specific deletion of arcuate Y2 receptors recapitulates the Npy‐null stress response, coincident with elevated serum noradrenaline. Importantly, specific reintroduction of NPY solely in noradrenergic neurons of otherwise Npy‐null mice blocks the increase in circulating noradrenaline and the stress‐induced bone loss. Thus, NPY protects against excessive stress‐induced bone loss, through Y2 receptor‐mediated modulation of central and peripheral noradrenergic neurons. © 2014 American Society for Bone and Mineral Research. 相似文献
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This report describes the production and characterization of 13 rodent monoclonal antibodies to the human erythrocyte anion transport protein AE1 (syn. band 3). Eleven antibodies (4 murine and 7 rat) recognize epitopes dependent on the integrity of the third extracellular loop of the protein. Two antibodies (1 murine and 1 rat) recognize epitopes on the N-terminal cytoplasmic domain. Quantitative binding studies using radioiodinated IgG and Fab fragments of antibodies to extracellular epitopes on AE1 ranged from 77,000 to 313,000 (IgG) and from 241,000 to 772,000 (Fab) molecules bound at saturation. The results indicate that the epitopes recognized by different antibodies vary in their accessibility and suggest that there is heterogeneity in the organization of individual AE1 molecules in the red blood cell membrane. Quantitative binding studies on South East Asian ovalocytes using several antibodies to AE1 and an anti-Wrb show a marked reduction in the number of antibody molecules bound at saturation. These results are consistent with the existence of highly cooperative interactions between transmembrane domains of AE1 in normal erythrocytes and the disruption of these interactions in the variant AE1 found in South East Asian ovalocytes. 相似文献