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61.
Patients with germinal center B cell-like (GCB) and non-GCB diffuse large B cell lymphomas (DLBCL) receiving first line therapy have distinct prognosis. We explored the differences in outcome following salvage autologous hematopoietic stem cell (HSC) transplantation between patients with GCB and non-GCB DLBCL. Forty-four patients with relapsed and 15 patients with primary refractory chemosensitive disease undergoing BEAM (BCNU [carmustine], etoposide, cytarabine, melphalan) conditioning and autologous HSC were included. Immunohistochemical analysis was performed for CD10, BCL-6, MUM1 (allowing classification into GCB and non-GCB-like DLBCL) and BCL-2. Median follow-up of survivors was 25 months; median age at the time of transplantation was 60 years (range 17–77). Thirty-two patients (54%) were classified as having GCB and 27 (46%) as having non-GCB-like DLBCL. Patients with GCB and non-GCB DLBCL did not differ in the risk of progression after HSC transplant ( P  = 0·78) or overall survival ( P  = 0·48). In multivariate analysis, only time to progression after initial treatment impacted overall survival. We conclude that patients with relapsed or primary refractory chemosensitive GCB and non-GCB-like DLBCL derive similar benefit from autologous HSC transplant.  相似文献   
62.
Objectives:  Mantle cell lymphoma (MCL) is an incurable B cell lymphoma, and novel treatment strategies are urgently needed. We evaluated the effects of combined treatment with the proteasome inhibitor bortezomib and the histone deacetylase inhibitor (HDACi) suberoylanilide hydroxamic acid (SAHA) on MCL. Bortezomib acts by targeting the proteasome, and – among other mechanisms – results in a reduced nuclear factor-kappa B (NF-κB) activity. HDACi promote histone acetylation, and also interfere with NF-κB signaling.
Methods:  Human MCL cell lines (JeKo-1, Granta-519 and Hbl-2) were exposed to bortezomib and/or SAHA. Cell viability and apoptosis were quantified by the MTT and annexin-V assay, respectively. Reactive oxygen species (ROS) were analyzed using the fluorophore H2DCFDA. In addition, activated caspases, proteasome- and NF-κB activity were quantified.
Results:  Combined incubation with bortezomib and SAHA resulted in synergistic cytotoxic effects, as indicated by combination index values <1 using the median effect method of Chou and Talalay. The combination of both inhibitors led to a strong increase in apoptosis as compared to single agents and was accompanied by enhanced ROS generation, while each agent alone only modestly induced ROS. The free radical scavenger N -acetyl- l -cysteine blocked the ROS generation and reduced the apoptosis significantly. In addition, coexposure of bortezomib and SAHA led to increased caspase-3, -8 and -9 activity, marked reduction of proteasome activity and decrease of NF-κB activity.
Conclusions:  This is the first report giving evidence that SAHA and bortezomib synergistically induce apoptosis in MCL cells. These data build the framework for clinical trials using combined proteasome and histone deacetylase inhibition in the treatment of MCL.  相似文献   
63.
The Quality of Well-Being (QWB) Scale is a utility-weighted measure of health-related quality of life that can be used in clinical trials, population studies, and cost/utility analyses. This article reports evidence for the validity of the QWB in patients with Alzheimer's disease. The subjects were 211 patient-spouse dyads and control dyads recruited from the University of California, San Diego, Alzheimer's Disease Research Center (ADRC) and from community referrals. Among these, three quarters were patients, and one quarter were age- and gender-matched controls. Patient data were obtained by caregiver proxy. Analyses demonstrated that the QWB was strongly associated with dementia ratings and behavioral problems. Caretakers of patients with low QWB scores also reported using more respite time. The authors conclude that the general QWB score allows data from Alzheimer's disease studies to be used in comparative cost/utility analysis.  相似文献   
64.
OBJECTIVES: The aim of this research was to assess the incidence, clinical predictors, and outcome of contrast-induced nephropathy (CIN) after primary percutaneous coronary intervention (PCI) for acute myocardial infarction (AMI). BACKGROUND: Contrast-induced nephropathy is associated with significant morbidity and mortality after PCI. Patients undergoing primary PCI may be at higher risk of CIN because of hemodynamic instability and unfeasibility of adequate prophylaxis. METHODS: In 208 consecutive AMI patients undergoing primary PCI, we measured serum creatinine concentration (Cr) at baseline and each day for the following three days. Contrast-induced nephropathy was defined as a rise in Cr >0.5 mg/dl. RESULTS: Overall, CIN occurred in 40 (19%) patients. Of the 160 patients with baseline Cr clearance >/=60 ml/min, only 21 (13%) developed CIN, whereas it occurred in 19 (40%) of those with Cr clearance <60 ml/min (p < 0.0001). In multivariate analysis, age >75 years (odds ratio [OR] 5.28, 95% confidence interval [CI] 1.98 to 14.05; p = 0.0009), anterior infarction (OR 2.17, 95% CI 0.88 to 5.34; p = 0.09), time-to-reperfusion >6 h (OR 2.51, 95% CI 1.01 to 6.16; p = 0.04), contrast agent volume >300 ml (OR 2.80, 95% CI 1.17 to 6.68; p = 0.02) and use of intraaortic balloon (OR 15.51, 95% CI 4.65 to 51.64; p < 0.0001) were independent correlates of CIN. Patients developing CIN had longer hospital stay (13 +/- 7 days vs. 8 +/- 3 days; p < 0.001), more complicated clinical course, and significantly higher mortality rate (31% vs. 0.6%; p < 0.001). CONCLUSIONS: Contrast-induced nephropathy frequently complicates primary PCI, even in patients with normal renal function. It is associated with higher in-hospital complication rate and mortality. Thus, preventive strategies are needed, particularly in high-risk patients.  相似文献   
65.
Acute renal failure (ARF) requiring hemodialysis after percutaneous coronary interventions (PCI) is a serious complication with poor prognosis. Hemodialysis-induced hypotension may have deleterious cardiovascular effects, especially in high-risk patients. Ultrafiltrate removal and simultaneous fluid replacement with a solution similar to plasma for high-volume controlled hydration can be obtained with hemodynamic stability by continuous veno-venous hemofiltration (CVVH). We prospectively assessed the safety and effectiveness of percutaneous CVVH (Y-shaped double-lumen catheter, circuit originating from and terminating in the femoral vein) in 33 consecutive patients (23 men and 10 women; mean age, 69 +/- 9 years) who, after PCI, developed oligo-anuric ARF, associated in 20 of them with congestive heart failure. All patients received a concomitant infusion of furosemide (500-1000 mg/day) and dopamine (2 microg/kg/min). During CVVH, the average fluid volume replacement and body fluid net reduction were 1000 +/- 247 and 75 +/- 48 ml/hr, respectively. Treatment with CVVH continued for 4.7 +/- 2.7 days and corrected fluid overload in all cases. No patient experienced systemic hypotension or hypovolemia. Diuresis recovered in 32 (97%) patients, who showed a parallel improvement of renal function parameters. One patient required chronic dialysis. In-hospital and 1-year mortality was 9.1% and 27.3%, respectively. In conclusion, our data indicate that CVVH is a safe and effective therapy of radiocontrast-induced ARF following PCI. It temporarily replaces renal function without deleterious cardiovascular effects, allowing the kidney to recover from the nephrotoxic injury. However, despite promising early results, large randomized trials are required to define the role of CVVH in ARF after PCI.  相似文献   
66.
67.
The clinical, histopathological, and electron microscopic features of an unusual case of xanthogranulomatous appendicitis are reported. The patient, a 37-year-old female, presented with typical signs of acute appendicitis and the appendix appeared slightly dilated at laparatomy. The histopathological sections showed numerous xanthoma cells mixed with inspissated fecaliths. Electron microscopy disclosed the presence of xanthoma cells filled with electron-lucent lipid droplets of variable size. The ultrastructural characteristics of these cells enabled the distinction of two types of lipid-laden histiocytes, in relationship to the size of the lipid droplets. Since the lipid droplets were seen also in cells other than histiocytes, it appears that these changes are secondary to a common mechanism,comprising factors such as obstruction, hemorrhage, inflammation,and local hypoxia.  相似文献   
68.
It is known that tetanus toxoid (TTd)-hyperimmunization induces increased titer of sera β2-glycoprotein I (β2GPI)-specific antibodies (Abs) in Balb/c mice. The concentrations of such induced anti-β2GPI Abs as well as their pathogenic potential are strongly influenced by the context of TTd application. β2GPI-specific immune response is established as a part of TTd-specific immune response by molecular mimicry mechanism due to structural homology between TTd and β2GPI. This finding is supported by the following facts: (1) cross-reactive Abs that recognize both TTd and β2GPI epitopes are present in Balb/c mice sera; (2) anti-TTd Abs secretion in splenic cultures is induced after β2GPI stimulation and vice versa. However, analyses of (1) IL-10 production following in vitro stimulation of immunized Balb/c mice splenocytes by TTd, β2GPI or glutaraldehyde-treated β2GPI and (2) specific impact of ConA and agonists of TLR2, TLR4, and TLR9 on anti-TTd and autoreactive Abs secretion strongly imply that these two branches of the TTd-induced immune response do not use identical cell populations and are regulated in a different way. Results presented in this paper describe that structural homology between foreign and self-antigens could focus mounted autoreactive immune response toward specific self-structure, but the context of antigen application, including a history of previous immune stimulations and adjuvants applied together with the antigen, are the main factors which determine the outcome of the induced immune response.  相似文献   
69.
70.
Abstract

Delivery of drugs from contact lens materials is attractive for a number of reasons. However, the controlled delivery of hydrophilic drugs can be difficult to achieve due to the burst release of drug that is associated with materials of high water content, such as hydrogels. Silicone hydrogels have significant potential for drug delivery due to their increased hydrophobicity and the tortuous nature of the pores, overcoming some of the limitations associated with conventional hydrogel materials. The aim of this study was to examine the potential of model poly(ethylene glycol) (PEG) containing silicone hydrogels for delivery of hydrophilic aminoglycoside antibiotics. It was hypothesized that PEG, a polymer that has seen extensive use in biomedical applications, will provide in addition to hydrophilicity and protein repulsion, a mechanism for controlling the delivery of this hydrophilic antibiotic. PEG was combined with the macromer TRIS to create the model silicone hydrogel materials. The optical and physical properties of the novel TRIS-co-PEG silicone hydrogels exhibited excellent transparency, appropriate refractive index and high transmittance indicating minimal phase separation. Desirable properties such as wettability and protein repulsion were maintained across a wide range of formulations. The water content was found to be highly correlated with the ethylene oxide content. Drug release could be influenced through PEG content and was found to fit Higuchi-like kinetics. Overall, the study demonstrates that incorporation of PEG into a model silicone hydrogel could be used to control the release of a hydrophilic compound. Data suggests this is related to the unique structure and properties of PEG, which alter the types of water found in each formulation and the water content.  相似文献   
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