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81.
82.
Charles E. Ray Catherine Battaglia Anne M. Libby Allan Prochazka Stan Xu Brian Funaki 《Journal of vascular and interventional radiology : JVIR》2012,23(3):306-314
PurposeTo determine whether there is a cost advantage for one of the three commonly performed interventional radiology (IR) procedures (chemoembolization, selective internal radiation therapy [SIRT], radiofrequency ablation [RFA]) in the treatment of hepatocellular carcinoma (HCC).Materials and MethodsA cost analysis from the payer perspective was performed. Primary data were collected from a university hospital, and sensitivity testing was done by comparing coding information obtained at two other tertiary care medical facilities. Medicare allowable reimbursements were used to estimate costs. Decision analytic models using decision tree analysis and Monte Carlo simulations were used to compare alternatives. Simulations were performed comparing all three procedures, followed by a two-way comparison of chemoembolization and SIRT.ResultsSimple decision tree analyses showed that RFA was less expensive compared with chemoembolization and SIRT. Monte Carlo simulations showed average reimbursements for each of the three procedures that was largely dependent on the number of repeat procedures required ($9,362 vs $30,107 vs $35,629 for RFA, chemoembolization, and SIRT; P < .001). When comparing only chemoembolization and SIRT, chemoembolization was the lower cost strategy in most scenarios, but SIRT was lower in cost in more than one-third of the simulations.ConclusionsRFA was the least costly of the three IR strategies in nearly all scenarios studied in these models. Although chemoembolization was less expensive than SIRT in most instances, Monte Carlo simulation showed a preference for SIRT in more than one-third of all scenarios. Sensitivity analyses showed that the most important variables assessed were the need for repeat procedures. 相似文献
83.
Kawakami A Osaka M Aikawa M Uematsu S Akira S Libby P Shimokado K Sacks FM Yoshida M 《Circulation research》2008,103(12):1402-1409
Apolipoprotein (apo)CIII predicts risk for coronary heart disease. We recently reported that apoCIII directly activates human monocytes. Recent evidence indicates that toll-like receptor (TLR)2 can contribute to atherogenesis through transduction of inflammatory signals. Here, we tested the hypothesis that apoCIII activates human monocytoid THP-1 cells through TLR2. ApoCIII induced the association of TLR2 with myeloid differentiation factor 88, activated nuclear factor (NF)-kappaB in THP-1 cells, and increased their adhesion to human umbilical vein endothelial cells (HUVECs). Anti-TLR2 blocking antibody, but not anti-TLR4 blocking antibody or isotype-matched IgG, inhibited these processes (P<0.05). ApoCIII bound with high affinity to human recombinant TLR2 protein and showed a significantly higher (P<0.05) and saturable binding to 293 cells overexpressing human TLR2 than to parental 293 cells with no endogenous TLR2. Overexpression of TLR2 in 293 cells augmented apoCIII-induced NF-kappaB activation and beta(1) integrin expression, processes inhibited by anti-apoCIII antibody as well as anti-TLR2 antibody. Exposure of peripheral blood monocytes isolated from C57BL/6 (wild-type) mice to apoCIII activated their NF-kappaB and increased their adhesiveness to HUVECs. In contrast, apoCIII did not activate monocytes from TLR2-deficient mice. Finally, intravenous administration to C57BL/6 mice of apoCIII-rich very-low-density lipoprotein (VLDL), but not of apoCIII-deficient VLDL, activated monocytes and increased their adhesiveness to HUVECs, processes attenuated by anti-TLR2 or anti-apoCIII antibody. ApoCIII-rich VLDL did not activate monocytes from TLR2-deficient mice. In conclusion, apoCIII activated monocytes at least partly through a TLR2-dependent pathway. The present study identifies a novel mechanism for proinflammatory and proatherogenic effects of apoCIII and a role for TLR2 in atherosclerosis induced by atherogenic lipoproteins. 相似文献
84.
Graziani G; Pasqualetti D; Lopez M; D'Onofrio C; Testi AM; Mandelli F; Gallo RC; Bonmassar E 《Blood》1987,69(4):1175-1181
Peripheral mononuclear cells (MNC) collected from 12 healthy donors and 44 leukemic patients at various stages of the disease were tested for natural killer (NK) activity and for their susceptibility to HTLV-I infection in vitro, measured in terms of percentage of p19 positive cells. MNC from leukemic donors at any stage of leukemia (ie, onset or relapse, ON/REL; complete remission or off-therapy, CR/OT donors) were highly susceptible to HTLV-I infection. This was true for acute leukemias of lymphoblastic (ALL) or nonlymphoblastic (ANLL) type. MNC of ON/REL patients were more susceptible to HTLV-I than those of CR/OT donors. In addition, leukemic blasts were more rapidly infected (ie, within five to seven days) than the HTLV-I-susceptible normal cord- blood lymphocytes. However, the presence of circulating blasts was not essential to virus susceptibility, since CR/OT MNC, presumably free of leukemic blasts, were still more susceptible to HTLV-I than normal cells. Basal NK function of MNC from leukemic patients was significantly lower than that detectable in healthy controls. However, no correlation was found between susceptibility to HTLV-I infection and NK activity. 相似文献
85.
Liu J Sukhova GK Sun JS Xu WH Libby P Shi GP 《Arteriosclerosis, thrombosis, and vascular biology》2004,24(8):1359-1366
Atherosclerosis is an inflammatory disease characterized by extensive remodeling of the extracellular matrix architecture of the arterial wall. Although matrix metalloproteinases and serine proteases participate in these pathologic events, recent data from atherosclerotic patients and animals suggest the participation of lysosomal cysteine proteases in atherogenesis. Atherosclerotic lesions in humans overexpress the elastolytic and collagenolytic cathepsins S, K, and L but show relatively reduced expression of cystatin C, their endogenous inhibitor, suggesting a shift in the balance between cysteine proteases and their inhibitor that favors remodeling of the vascular wall. Extracts of human atheromatous tissue show greater elastolytic activity in vitro than do those from healthy donors. The cysteinyl protease inhibitor E64d limits this increased elastolysis, indicating involvement of cysteine proteases in elastin degradation during atherogenesis. Furthermore, inflammatory cytokines augment expression and secretion of active cysteine proteases from cultured monocyte-derived macrophages, vascular smooth muscle cells, and endothelial cells and increase degradation of extracellular elastin and collagen. Cathepsin S-deficient cells or those treated with E64d show significantly impaired elastolytic or collagenolytic activity. Additionally, recent in vivo studies of atherosclerosis-prone, LDL receptor-null mice lacking cathepsin S show participation of this enzyme in the initial infiltration of leukocytes, medial elastic lamina degradation, endothelial cell invasion, and neovascularization, illustrating an important role for cysteine proteases in arterial remodeling and atherogenesis. 相似文献
86.
Henschke CI Yankelevitz DF Libby D McCauley D Pasmantier M Smith JP 《Clinics in Chest Medicine》2002,23(1):49-57, viii
The development of CT technology reopened the lung cancer screening debate. Computed tomography screening for lung cancer certainly meets all the criteria required for an appropriate screening test. First and perhaps most importantly, the disease for which the screening is being performed should have a significant prevalence in the population being studied and be a significant health risk for those afflicted with it. Lung cancer is the leading cause of cancer death in both men and women, and one of the most lethal of all cancers. 相似文献
87.
The healthy endothelium usually provides an anticoagulant, vasodilatory and anti-inflammatory spectrum of functions that are central in vascular homeostasis. Dysfunction of the endothelium is a common feature of all phases of atherosclerosis. Hypercholesterolemia provokes many aspects of endothelial dysfunction before and during the development of atheroma. For example, a high cholesterol diet leads to the formation of a fatty streak and the recruitment and binding of blood leukocytes to the artery wall. This process requires expression by the endothelial cells of adhesion molecules such as vascular cell adhesion molecule-1 (VCAM-1). In rabbits that are fed an atherogenic diet, the aortic endothelium, which usually expresses little VCAM-1, shows foci of VCAM-1 expression soon after initiating this diet. Furthermore, lowering plasma cholesterol by diet or drugs down-regulates the expression of VCAM-1 and reduces the density of inflammatory cells in the atherosclerotic plaque. Hypercholesterolemia also attenuates normal vasodilatation to several stimuli such as exercise and acetylcholine. In healthy subjects, the vascular endothelium produces the vasodilator nitric oxide. In atherosclerosis, however, nitric oxide bioavailability is impaired. As a result, atherosclerotic coronary arteries commonly display a vasoconstrictor response when challenged with acetylcholine. Lipid lowering appears to favorably influence endothelial vasomotor and inflammatory functions in ways that may benefit patients with coronary artery disease. Continued probing of the basic mechanisms of endothelial dysfunction and its treatment may lead to new therapies that offer clinical benefits in patients with atherosclerosis, including reductions in coronary events. 相似文献
88.
Jacqueline AM Smith DL Patil OT Daniels Y-S Ding J-D Gallezot S Henry KHS Kim S Kshirsagar WJ Martin GP Obedencio E Stangeland PR Tsuruda W Williams RE Carson ST Patil 《The international journal of neuropsychopharmacology / official scientific journal of the Collegium Internationale Neuropsychopharmacologicum (CINP)》2015,18(2)
Background:
Monoamine reuptake inhibitors exhibit unique clinical profiles that reflect distinct engagement of the central nervous system (CNS) transporters.Methods:
We used a translational strategy, including rodent pharmacokinetic/pharmacodynamic modeling and positron emission tomography (PET) imaging in humans, to establish the transporter profile of TD-9855, a novel norepinephrine and serotonin reuptake inhibitor.Results:
TD-9855 was a potent inhibitor of norepinephrine (NE) and serotonin 5-HT uptake in vitro with an inhibitory selectivity of 4- to 10-fold for NE at human and rat transporters. TD-9855 engaged norepinephrine transporters (NET) and serotonin transporters (SERT) in rat spinal cord, with a plasma EC50 of 11.7ng/mL and 50.8ng/mL, respectively, consistent with modest selectivity for NET in vivo.Accounting for species differences in protein binding, the projected human NET and SERT plasma EC50 values were 5.5ng/mL and 23.9ng/mL, respectively. A single-dose, open-label PET study (4–20mg TD-9855, oral) was conducted in eight healthy males using the radiotracers [11C]-3-amino-4- [2-[(di(methyl)amino)methyl]phenyl]sulfanylbenzonitrile for SERT and [11C]-(S,S)-methylreboxetine for NET. The long pharmacokinetic half-life (30–40h) of TD-9855 allowed for sequential assessment of SERT and NET occupancy in the same subject. The plasma EC50 for NET was estimated to be 1.21ng/mL, and at doses of greater than 4mg the projected steady-state NET occupancy is high (>75%). After a single oral dose of 20mg, SERT occupancy was 25 (±8)% at a plasma level of 6.35ng/mL.Conclusions:
These data establish the CNS penetration and transporter profile of TD-9855 and inform the selection of potential doses for future clinical evaluation. 相似文献89.
90.
Monika Oláhová Tobias B Haack Charlotte L Alston Jessica AC Houghton Langping He Andrew AM Morris Garry K Brown Robert McFarland Zofia MA Chrzanowska-Lightowlers Robert N Lightowlers Holger Prokisch Robert W Taylor 《European journal of human genetics : EJHG》2015,23(7):935-939
Isolated mitochondrial complex IV (cytochrome c oxidase) deficiency is an important cause of mitochondrial disease in children and adults. It is genetically heterogeneous, given that both mtDNA-encoded and nuclear-encoded gene products contribute to structural components and assembly factors. Pathogenic variants within these proteins are associated with clinical variability ranging from isolated organ involvement to multisystem disease presentations. Defects in more than 10 complex IV assembly factors have been described including a recent Lebanese founder mutation in PET100 in patients presenting with Leigh syndrome. We report the clinical and molecular investigation of a patient with a fatal, neonatal-onset isolated complex IV deficiency associated with multiorgan involvement born to consanguineous, first-cousin British Asian parents. Exome sequencing revealed a homozygous truncating variant (c.142C>T, p.(Gln48*)) in the PET100 gene that results in a complete loss of enzyme activity and assembly of the holocomplex. Our report confirms PET100 mutation as an important cause of isolated complex IV deficiency outside of the Lebanese population, extending the phenotypic spectrum associated with abnormalities within this gene. 相似文献