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31.
Martin-Carbonero L Barrios A Saballs P Sirera G Santos J Palacios R Valencia ME Alegre M Podzamczer D González-Lahoz J;Caelyx/KS Spanish Group 《AIDS (London, England)》2004,18(12):1737-1740
Twenty-eight HIV patients either naive or failing highly active antiretroviral therapy (HAART)with moderate-advanced Kaposi's sarcoma (KS)were randomly chosen to initiate a new HAART regimen plus pegylated liposomal doxorubicin(PLD) or the new HAART regimen alone. After 48 weeks, better response rates were observed in the HAART plus PLD group (76% versus 20%).In HIV-infected patients with moderate-advanced KS, HAART alone may not be enough for KS response. 相似文献
32.
Thomson KJ Hart DP Banerjee L Ward KN Peggs KS Mackinnon S 《Bone marrow transplantation》2005,35(11):1065-1069
Patients undergoing haemopoietic stem cell transplants (HSCT) are at high risk of varicella zoster virus (VZV) reactivation, with a significant incidence of dissemination. This study reports a retrospective analysis of 247 allogeneic HSCT recipients receiving anti-viral prophylaxis with low-dose oral aciclovir 400 mg/day, administered until immunosuppression was discontinued and the CD4(+) cell count exceeded 200/mm(3). Viral reactivation was successfully suppressed by aciclovir prophylaxis, with only one case of breakthrough infection. The cumulative incidence of zoster infection at 1 year post transplant was 2% and at 5 years 34%. In all, 64 patients discontinued prophylaxis. Zoster developed in 26 of these, giving a cumulative incidence of infection at 1 year after stopping aciclovir of 39% and at 3 years 44%. Infection occurred in a localised dermatomal distribution in 93% of cases. This supports previous findings that aciclovir prophylaxis prevents early VZV reactivation, although the long-term incidence is not affected as infection occurs once prophylaxis is discontinued. Such infection, however, is mild and localised. This study does not support the idea that use of such low-dose aciclovir regimens reduces the zoster incidence by permitting subclinical reactivation during prophylaxis, and therefore the re-establishment of protective anti-viral immunity. 相似文献
33.
Emil KS Espe Jan Magnus Aronsen Kristine Sk?rdal Jürgen E Schneider Lili Zhang Ivar Sjaastad 《Journal of cardiovascular magnetic resonance》2013,15(1):82
Background
Phase contrast velocimetry cardiovascular magnetic resonance (PC-CMR) is a powerful and versatile tool allowing assessment of in vivo motion of the myocardium. However, PC-CMR is sensitive to motion related artifacts causing errors that are geometrically systematic, rendering regional analysis of myocardial function challenging. The objective of this study was to establish an optimized PC-CMR method able to provide novel insight in the complex regional motion and strain of the rodent myocardium, and provide a proof-of-concept in normal and diseased rat hearts with higher temporal and spatial resolution than previously reported.Methods
A PC-CMR protocol optimized for assessing the motion and deformation of the myocardium in rats with high spatiotemporal resolution was established, and ten animals with different degree of cardiac dysfunction underwent examination and served as proof-of-concept. Global and regional myocardial velocities and circumferential strain were calculated, and the results were compared to five control animals. Furthermore, the global strain measurements were validated against speckle-tracking echocardiography, and inter- and intrastudy variability of the protocol were evaluated.Results
The presented method allows assessment of regional myocardial function in rats with high level of detail; temporal resolution was 3.2 ms, and analysis was done using 32 circumferential segments. In the dysfunctional hearts, global and regional function were distinctly altered, including reduced global peak values, increased regional heterogeneity and increased index of dyssynchrony. Strain derived from the PC-CMR data was in excellent agreement with echocardiography (r = 0.95, p < 0.001; limits-of-agreement −0.02 ± 3.92%strain), and intra- and interstudy variability were low for both velocity and strain (limits-of-agreement, radial motion: 0.01 ± 0.32 cm/s and −0.06 ± 0.75 cm/s; circumferential strain: -0.16 ± 0.89%strain and −0.71 ± 1.67%strain, for intra- and interstudy, respectively).Conclusion
We demonstrate, for the first time, that PC-CMR enables high-resolution evaluation of in vivo circumferential strain in addition to myocardial motion of the rat heart. In combination with the superior geometric robustness of CMR, this ultimately provides a tool for longitudinal studies of regional function in rodents with high level of detail. 相似文献34.
Dyskinesia, secondary to dopamine replacement therapy, is the major complication of currently available therapies for Parkinson's disease. Alpha(2) adrenoceptor antagonists, such as idazoxan, can significantly reduce levodopa-induced dyskinesia in the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-lesioned, nonhuman primate model of Parkinson's disease and in human. This action of adrenoceptor antagonists may involve blockade of the actions of noradrenaline synthesised from levodopa. We hypothesise that, because dopamine receptor agonists, such as apomorphine, cannot be metabolised to produce noradrenaline, activation of adrenoceptors may not be involved in dyskinesia produced by such agents. If this were the case, idazoxan would not be expected to reduce apomorphine-induced dyskinesia. MPTP-lesioned marmosets with stable dyskinesia induced by prolonged levodopa therapy were given an acute challenge with apomorphine (0.3 mg/kg subcutaneously) or levodopa (8.0 mg/kg orally), these doses produced equivalent peak-dose dyskinesia. Idazoxan (2.5 mg/kg p.o.), or vehicle, was then administered with either apomorphine or levodopa. Idazoxan abolished levodopa-induced dyskinesia but did not affect apomorphine-induced dyskinesia (P < 0.05 and P > 0.05, respectively, Wilcoxon matched pairs test). Idazoxan also extended the anti-parkinsonian actions of levodopa but did not affect those of apomorphine. The pharmacological characteristics of the neural mechanisms underlying levodopa-induced dyskinesia and apomorphine-induced dyskinesia in parkinsonism thus appear to be distinct, at least with respect to the involvement of alpha(2) adrenoceptors. Specifically, levodopa, but not apomorphine-induced dyskinesia, involves activation of adrenoceptors. This finding may have major implications for understanding dyskinesia and should be borne in mind when designing clinical studies in which levodopa or dopamine receptor agonist challenges are employed to assess potential anti-dyskinetic properties of drugs. 相似文献
35.
Peggs KS Sureda A Qian W Caballero D Hunter A Urbano-Ispizua A Cavet J Ribera JM Parker A Canales M Mahendra P Garcia-Conde J Milligan D Sanz G Thomson K Arranz R Goldstone AH Alvarez I Linch DC Sierra J Mackinnon S;UK Spanish Collaborative Groups 《British journal of haematology》2007,139(1):70-80
The introduction of reduced-intensity conditioning (RIC) has enabled the role of allogeneic transplantation to be re-evaluated in Hodgkin lymphoma (HL). While T-cell depletion reduces graft-versus-host disease (GvHD), it potentially abrogates graft-versus-tumour activity and increases infective complications. We compared the results in 67 sibling donor transplantations following RIC in multiply relapsed patients from two national phase II studies conditioned with fludarabine/melphalan. One used cyclosporine/alemtuzumab (MF-A, n = 31), the other used cyclosporine/methotrexate (MF, n = 36) as GvHD prophylaxis. There was a small excess of chemorefractory cases in the MF cohort (P = NS). MF-A resulted in significantly lower incidences of non-relapse mortality, acute and chronic GvHD, but no significant excess of relapse/progression. Post donor lymphocyte infusion (DLI) disease responses occurred in 8/14 (57%) and 6/11 (55%) patients in the MF-A and MF groups, respectively. Current progression-free survival (CPFS) was superior with MF-A (univariate analysis), with durable responses to DLI contributing to the favourable outcome (43% vs. 25%, P = 0.0356). Disease status at transplantation significantly influenced overall survival (P = 0.0038) and CPFS (P = 0.0014), retaining significance in multivariate analyses, which demonstrated a trend towards improved CPFS with T-cell depletion (P = 0.0939). These data suggest that alemtuzumab significantly reduced GvHD without resulting in a deleterious impact on survival outcomes following RIC in HL, and that durable responses to DLI may be more common following the inclusion of alemtuzumab in the conditioning protocol. 相似文献
36.
37.
Background
Despite extensive research, the five-year survival rate of oral squamous cell carcinoma (OSCC) patients has not improved. Effective treatment of OSCC requires the identification of molecular targets and signaling pathways to design appropriate therapeutic strategies. Several genes from the mTOR signaling pathway are known to be dysregulated in a wide spectrum of cancers. However, not much is known about the involvement of this pathway in tumorigenesis of OSCC. We therefore investigated the role of the tumor suppressor genes, TSC1 and TSC2, and other members of this pathway in tumorigenesis of OSCC. 相似文献38.
Effects of positive and negative pressure ventilation on cerebral blood volume of newborn infants 总被引:3,自引:0,他引:3
KS Palmer SA Spencer YABD Wickramasinghe T Wright DP Southall P Rolfe 《Acta paediatrica (Oslo, Norway : 1992)》1995,84(2):132-139
The effects of intermittent positive airway and continuous negative extrathoracic pressure ventilation on cerebral blood volume in preterm infants were studied using near infrared spectroscopy. In 12 infants continuous negative extrathoracic pressure caused a median decrease in cerebral blood volume of 0.14ml/100ml brain (95% confidence intervals (CI) 0.035–0.280) compared with no respiratory support. Oxygenated and deoxygenated haemoglobin also decreased, implying increased venous drainage as the main effect. In 17 infants intermittent positive pressure ventilation also caused a median reduction in cerebral blood volume of 0.06 ml/100 ml brain (95% CI 0.010–0.115) compared with endotracheal positive airway pressure. Deoxygenated haemoglobin increased by 0.07 ml/100 ml brain (95% CI 0.010–0.100) while oxygenated haemoglobin decreased by O.lOml/lOOml brain (95% CI 0.005–0.175). The increase in deoxygenated haemoglobin implies decreased venous drainage and the decrease in oxygenated haemoglobin implies that other factors may also be significant. Heart rate, blood pressure and oxygen saturation were monitored continuously and remained stable. 相似文献
39.
Morris EC Rebello P Thomson KJ Peggs KS Kyriakou C Goldstone AH Mackinnon S Hale G 《Blood》2003,102(1):404-406
Persistence of alemtuzumab at lympholytic concentrations after reduced-intensity conditioning allogeneic stem cell transplantations (RITs) could impair immune reconstitution and reduce donor T-cell-mediated graft-versus-leukemia/lymphoma (GVL) effects, derived from the graft or subsequent adoptive immunotherapy. We have studied the pharmacokinetics of alemtuzumab in 2 different groups: RIT (100 mg alemtuzumab in vivo over 5 days) and myeloablative allografts (20 mg alemtuzumab added in vitro to the stem cells prior to return). Alemtuzumab concentrations in RIT patients were in excess of that required to kill infused donor CD52+ cells at the time of transplantation and remained at potentially lympholytic levels (> 0.1 microg/mL) for approximately 56 days after transplantation, 26 days longer than for the myeloablative group. Total lymphocyte counts were significantly lower in the RIT group persisting beyond 6 months after transplantation (P =.005), and median absolute CD4 counts higher than 200 x 106/L were delayed until 9 months after transplantation. 相似文献
40.
Obesity is increasing in the United States, not only among adults, but also among children and youth (1). The U.S. Centers for Disease Control and Prevention report the incidence of children at risk for being overweight or obese has doubled in the last two decades (2). Schools can play a role in preventing childhood obesity by serving healthy meals with adequate calories and nutrients, providing nutrition education that encourages healthful food selections, offering opportunities for physical activity and creating school environments that model healthful behaviors. 相似文献