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71.
Aimee Spector Martin Orrell Stephen Davies Bob Woods 《Neuropsychological rehabilitation》2013,23(3-4):377-397
This study describes the development and implementation of a programme of cognition-based therapies for dementia. The programme was designed by distilling the evidence of the effectiveness of Reality Orientation and related approaches, following a broad-based systematic review. The most beneficial elements identified from previous studies were extracted and incorporated into the programme, using the expertise of specialists in the field. The programme comprised of 15 45-min, twice weekly sessions. It ran in one day centre and three residential homes, involving 27 people with dementia (17 treatment and 10 control subjects). The results of the pilot study showed positive trends in cognition, and trends towards reduced depression and anxiety following treatment. No negative effects were identified. We discuss how the outcomes of the pilot study were used to modify the programme, which now has a stronger cognitive element. This refined programme is currently being tested as part of a large multicentre, randomised controlled trial. 相似文献
72.
de Graauw M Le Dévédec S Tijdens I Smeets MB Deelder AM van de Water B 《The Journal of pharmacology and experimental therapeutics》2007,322(1):89-100
Toxicant exposure affects the activity of various protein tyrosine kinases. Using phosphotyrosine proteomics, we identified proteins that were differentially phosphorylated before renal cell detachment and apoptosis. Treatment of primary cultured rat proximal tubular epithelial cells with the model nephrotoxicant S-(1,2-dichlorovinyl)-L-cysteine (DCVC) resulted in early reorganization of F-actin stress fibers and formation of lamellipodia, which was followed by cell detachment from the matrix and apoptosis. This was prevented by genistein-mediated inhibition of protein tyrosine kinases and enhanced by inhibition of protein tyrosine phosphatases using vanadate. Phosphotyrosine proteomics revealed that DCVC-induced renal cell apoptosis was preceded by changes in the tyrosine phosphorylation status of a subset of proteins, as identified by matrix-assisted laser desorption ionization/time of flight-mass spectrometry (MS)/MS including actin-related protein 2 (Arp2), cytokeratin 8, t-complex protein 1 (TCP-1), chaperone containing TCP-1, and gelsolin precursor. The major differentially tyrosine-phosphorylated protein was Arp2, whereas phosphorylation of Arp3 was not affected. Arp2 was located in the lamellipodia that were formed before the onset of apoptosis. Because DCVC-induced cell detachment and apoptosis is regulated by tyrosine kinases, we propose that alterations in tyrosine phosphorylation of a subset of proteins, including Arp2, play a role in the regulation of the F-actin reorganization and lamellipodia formation that precede renal cell apoptosis caused by nephrotoxicants. 相似文献
73.
74.
Hypnotic abreaction releases chaotic patterns of electrodermal activity during dissociation 总被引:1,自引:0,他引:1
Bob P 《The International journal of clinical and experimental hypnosis》2007,55(4):435-456
Chaotic transitions emerge in a wide variety of cognitive phenomena and may possibly be linked to specific changes during development of mental disorders. There are several hypotheses that link the dissociation to critical chaotic shifts with the resulting self-organization of behavioral patterns during critical periods. In 2 patients, hypnotic revivification of dissociated trauma along with measurement of bilateral electrodermal activity (EDA) for therapeutic and research purposes was performed. Nonlinear data analysis of EDA records shows a difference between degree of chaos in hypnotic relaxed state before revivification of the trauma and dissociated state after reliving the traumatic memory. Results suggest that the dissociated state after revivification of the trauma is significantly more chaotic than the state during the hypnotic relaxation before the event. Findings of this study suggest a possible role of neural chaos in the processing of the dissociated traumatic memory during hypnotic revivification. 相似文献
75.
Anai S Goodison S Shiverick K Hirao Y Brown BD Rosser CJ 《Molecular cancer therapeutics》2007,6(1):101-111
Expression of the proto-oncogene Bcl-2 is associated with tumor progression. Bcl-2's broad expression in tumors, coupled with its role in resistance to chemotherapy and radiation therapy-induced apoptosis, makes it a rational target for anticancer therapy. Antisense Bcl-2 oligodeoxynucleotide (ODN) reagents have been shown to be effective in reducing Bcl-2 expression in a number of systems. We investigated whether treating human prostate cancer cells with antisense Bcl-2 ODN (G3139, oblimersen sodium, Genasense) before irradiation would render them more susceptible to radiation effects. Two prostate cancer cell lines expressing Bcl-2 at different levels (PC-3-Bcl-2 and PC-3-Neo) were subjected to antisense Bcl-2 ODN, reverse control (CTL), or mock treatment. Antisense Bcl-2 ODN alone produced no cytotoxic effects and was associated with G(1) cell cycle arrest. The combination of antisense Bcl-2 ODN with irradiation sensitized both cell lines to the killing effects of radiation. Both PC-3-Bcl-2 and PC-3-Neo xenografts in mice treated with the combination of antisense Bcl-2 ODN and irradiation were more than three times smaller by volume compared with xenografts in mice treated with reverse CTL alone, antisense Bcl-2 ODN alone, irradiation alone, or reverse CTL plus radiotherapy (P = 0.0001). Specifically, PC-3-Bcl-2 xenograft tumors treated with antisense Bcl-2 ODN and irradiation had increased rates of apoptosis and decreased rates of angiogenesis and proliferation. PC-3-Neo xenograft tumors had decreased proliferation only. This is the first study which shows that therapy directed at Bcl-2 affects tumor vasculature. Together, these findings warrant further study of this novel combination of Bcl-2 reduction and radiation therapy, as well as Bcl-2 reduction and angiogenic therapy. 相似文献
76.
77.
Geurt Stokman Yu Qin Tijmen H. Booij Sreenivasa Ramaiahgari Marie Lacombe M. Emmy M. Dolman Kim M.A. van Dorenmalen Gwendoline J.D. Teske Sandrine Florquin Frank Schwede Bob van de Water Robbert J. Kok Leo S. Price 《Journal of the American Society of Nephrology : JASN》2014,25(7):1474-1485
Activation of Rap1 by exchange protein activated by cAMP (Epac) promotes cell adhesion and actin cytoskeletal polarization. Pharmacologic activation of Epac-Rap signaling by the Epac-selective cAMP analog 8-pCPT-2′-O-Me-cAMP during ischemia-reperfusion (IR) injury reduces renal failure and application of 8-pCPT-2′-O-Me-cAMP promotes renal cell survival during exposure to the nephrotoxicant cisplatin. Here, we found that activation of Epac by 8-pCPT-2′-O-Me-cAMP reduced production of reactive oxygen species during reoxygenation after hypoxia by decreasing mitochondrial superoxide production. Epac activation prevented disruption of tubular morphology during diethyl maleate–induced oxidative stress in an organotypic three-dimensional culture assay. In vivo renal targeting of 8-pCPT-2′-O-Me-cAMP to proximal tubules using a kidney-selective drug carrier approach resulted in prolonged activation of Rap1 compared with nonconjugated 8-pCPT-2′-O-Me-cAMP. Activation of Epac reduced antioxidant signaling during IR injury and prevented tubular epithelial injury, apoptosis, and renal failure. Our data suggest that Epac1 decreases reactive oxygen species production by preventing mitochondrial superoxide formation during IR injury, thus limiting the degree of oxidative stress. These findings indicate a new role for activation of Epac as a therapeutic application in renal injury associated with oxidative stress.Renal ischemia-reperfusion (IR) injury is an important cause of AKI1 and a significant risk factor for the development of renal dysfunction after kidney transplantation.2 During IR injury, morphologic and functional alterations of the proximal tubular epithelium occur that are linked to the development of renal failure and activation of immune cells via release of proinflammatory cytokines.3Exchange protein activated by cAMP (Epac) is a guanine nucleotide exchange factor for the small GTPase Rap1.4 Activation of Epac by cAMP or by the Epac-selective cAMP analog 8-pCPT-2′-O-Me-cAMP (also referred to as 007) induces functional activation of Rap1.5 Initial studies showed that Epac-Rap signaling enhances cell adhesion by supporting maturation of cell-cell junctions6,7 and promoting integrin-mediated cell-matrix adhesion.8,9 In line with these studies, we recently demonstrated that selective activation of Epac reduces proximal tubular epithelial cell (PTEC) detachment during IR injury using in vitro and in vivo models.10 Activation of Epac-Rap was associated with reduced expression of markers for cellular stress in PTECs. In addition, in vitro cisplatin-induced apoptosis of PTECs could be significantly reduced by activation of Epac and this was also associated with improved adhesion of cells.11 On the basis of these findings, we hypothesized that activation of Epac-Rap signaling may protect against a common cytotoxic event in these injury models.Unbalanced and uncontrolled production of reactive oxygen species (ROS) is an important mediator of cell injury and occurs during cisplatin nephrotoxicity,12 IR injury,13 and renal fibrosis.14 In renal pathology, intracellular ROS can be produced enzymatically such as by NADPH oxidase (NOX) complexes or derive from dysfunctional mitochondrial activity. Mitochondrial ROS production appears to be the driving force behind hypoxia-reoxygenation cell injury15 and cisplatin cytotoxicity.16Here we studied the role of specific proximal tubular activation of Epac and how this protects against renal injury in both in vitro and in vivo models for IR injury. We found that ROS production during reoxygenation after hypoxia was decreased by activation of Epac. Selective proximal tubular activation of Epac by renal targeting of 8-pCPT-2′-O-Me-cAMP conjugated to lysozyme (LZM-007) reduced oxidative stress in an in vivo model for IR injury and significantly decreased IR injury–associated renal failure and tubular damage. Our data show that Epac activation reduces ROS-mediated cellular injury in renal disease and may be a therapeutic strategy for modulation of oxidative stress. 相似文献
78.
Darrell R. Boverhof Greg Ladics Bob Luebke Jane Botham Emanuela Corsini Ellen Evans Dori Germolec Michael Holsapple Scott E Loveless Haitian Lu Jan Willem van der Laan Kimber L. White Jr. Yung Yang 《Regulatory toxicology and pharmacology : RTP》2014
As experience is gained with toxicology testing and as new assays and technologies are developed, it is critical for stakeholders to discuss opportunities to advance our overall testing strategies. To facilitate these discussions, a workshop on practices for assessing immunotoxicity for environmental chemicals was held with the goal of sharing perspectives on immunotoxicity testing strategies and experiences, developmental immunotoxicity (DIT), and integrated and alternative approaches to immunotoxicity testing. Experiences across the chemical and pharmaceutical industries suggested that standard toxicity studies, combined with triggered-based testing approaches, represent an effective and efficient approach to evaluate immunotoxic potential. Additionally, discussions on study design, critical windows, and new guideline approaches and experiences identified important factors to consider before initiating DIT evaluations including assay choice and timing and the impact of existing adult data. Participants agreed that integrating endpoints into standard repeat-dose studies should be considered for fulfilling any immunotoxicity testing requirements, while also maximizing information and reducing animal use. Participants also acknowledged that in vitro evaluation of immunosuppression is complex and may require the use of multiple assays that are still being developed. These workshop discussions should contribute to developing an effective but more resource and animal efficient approach for evaluating chemical immunotoxicity. 相似文献
79.
Signe Düring Birte Y Glenth?j Gitte Saltoft Andersen Bob Oranje 《Neuropsychopharmacology》2014,39(13):3000-3008
It has been suggested that psychophysiological measures of sensory and sensorimotor gating, P50 gating and prepulse inhibition of the startle reflex (PPI), underlie core features of schizophrenia and are linked to dopaminergic pathways in the striatum and prefrontal cortex. In the present study, the effects of a potent D2/D3 receptor antagonist, amisulpride, were investigated on PPI and P50 gating in a large sample of antipsychotic-naive, first-episode patients with schizophrenia. A total of 52 initially antipsychotic-naive, first-episode schizophrenia patients were assessed for their P50 gating, PPI, and habituation/sensitization abilities at baseline and after 2 and 6 weeks of treatment with flexible doses of amisulpride. In addition, 47 matched healthy controls were assessed at baseline and after 6 weeks. At baseline, the patients showed significantly reduced PPI, yet normal levels of P50 gating, habituation, and sensitization. Treatment with amisulpride showed no effects on these measures, either at 2 or 6 weeks of follow-up. This is the first study investigating the effects of monotherapy with a relatively selective dopamine D2/D3 receptor antagonist (amisulpride) on sensory and sensorimotor gating deficits in a longitudinal study of a large group of initially antipsychotic-naive, first-episode patients with schizophrenia. Our finding that amisulpride effectively reduced symptom severity in our patients without reducing their PPI deficits indicates that increased activity of dopamine D2 receptors may be involved in symptomatology of patients with schizophrenia, but not in their sensorimotor gating deficits. 相似文献
80.
Naomi Holman PhD Peter Knighton MPhys Jackie OʼKeefe MSc Sarah H. Wild PhD Sarah Brewster MRCP Hermione Price FRCP Kiran Patel PhD Wasim Hanif MD Vinod Patel MD Edward W. Gregg PhD Richard I. G. Holt PhD Roger Gadsby MB Kamlesh Khunti MD Jonathan Valabhji MD Bob Young MD Naveed Sattar MD 《Diabetes, obesity & metabolism》2021,23(12):2728-2740