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41.
42.
OBJECTIVE: To estimate the 3-year incremental cost effectiveness and cost utility of introducing leflunomide into sequential therapy, consisting of the most frequently used disease-modifying antirheumatic drugs (DMARDs), for patients with rheumatoid arthritis in specialised, i.e. rheumatological, care in Germany. DESIGN AND SETTING: The analysis was conducted from the societal perspective in Germany using an existing 3-year simulation model, which was adapted to the German healthcare system after secondary analysis of relevant publications and data. DMARD sequences including leflunomide were compared with those excluding leflunomide. Costs comprised direct costs incurred by treatment and indirect costs incurred by loss of productivity (sick leave and premature retirement) of rheumatoid arthritis patients. Effectiveness parameters were given by response years gained (RYGs) according to the American College of Rheumatology (ACR) criteria for 20%, 50% and 70% improvement (ACR20/50/70RYGs) and by QALYs gained (QALYGs). Costs, effects and QALYs were discounted by 5% per annum. In the base-case analysis, average values of costs, response years and QALYs were applied. Costs were in 1998-2001 values (euro 1 approximately equal to $US 0.91, average of the period from the year 2000 through 2001). MAIN OUTCOME MEASURES AND RESULTS: After 3 years, adding leflunomide was less costly and more effective than the strategy excluding leflunomide when total (direct and indirect) costs were considered. There were savings of euro 271,777 and 8.1, 4.3, 5.1 and 4.9 ACR20RYGs, ACR50RYGs, ACR70RYGs and QALYGs per 100 patients, respectively, obtained through adding leflunomide. Focusing on direct costs, adding leflunomide was more costly and more effective compared with excluding leflunomide, with an incremental cost effectiveness of euro 5004 per ACR20RYG, euro 9535 per ACR50RYG, euro 7996 per ACR70RYG, and an incremental cost utility of euro8301 per QALYG, after 3 years. The robustness of the results was shown in comprehensive sensitivity analyses. In the analysis of extremes, different combinations of the limits of cost, effectiveness and utility parameters were investigated. Adding leflunomide to sequential DMARD therapy remained dominant in 79% of the possible cases, i.e. was less costly and more effective than the strategy excluding leflunomide. Focusing on direct costs, adding leflunomide became dominant in 29% and remained more costly and more effective in 50% of possible cases. CONCLUSIONS: Our analysis suggests, with its underlying data and assumptions, that having leflunomide as an additional option in a DMARD treatment sequence extends the time patients benefit from DMARD therapy at reasonable additional direct costs. Adding leflunomide may even be cost saving when total (direct and indirect) costs are considered. As data on DMARD effectiveness were extracted from the results of clinical trials, real-world data from observational studies would be needed to corroborate the findings of the present analysis.  相似文献   
43.
BACKGROUND: Xenograft rejection is associated with vascular inflammation, thrombocytopenia and the accelerated consumption of coagulation factors. Primary biological incompatibilities of the xenograft in the regulation of clotting appear to amplify pathological processes associated with rejection. The functional incompatibility of porcine von Willebrand factor (vWF) expressed within the xenograft vasculature may heighten interactions with the primate platelet receptor GPIb, hence augmenting formation of platelet microthrombi and vascular injury. Here, we address the functional impact of O-linked glycosylation of the vWF A1 domain on primate platelet activation. METHODS: Recombinant human or porcine vWF A1-domains were transiently over-expressed in COS-7 cells as FLAG-tagged fusion protein, linked to plasma membranes via GPI anchors. O-linked glycosylation was blocked by the addition of phenyl-alpha-GalNAc2 to cultures. Expressed vWF-A1 domains were characterized utilizing cytofluometric- and Western blot analyses. RESULTS: Cytofluometric analysis confirmed equivalent levels of human and porcine vWF A1-domain expression irrespective of the levels of O-linked glycosylation. Differential glycosylation patterns of vWF-A1 under these conditions were confirmed by Western blot analyses. Native porcine vWF A1-domains had enhanced human platelet activation potential when compared with human recombinant vWF A1. However, the loss of O-linked glycosylation abolished differences in aggregatory responses between human and porcine vWF A1 domains. CONCLUSIONS: Various degrees of O-linked glycosylation of vWF-A1-domains modulate levels of functional interaction with platelet receptor GPIb and consequent platelet aggregation responses in vitro. These data may have implications for outcomes of xenotransplantation. We speculate that alterations in glycosylation of vWF and other adhesion proteins associated with the targeting of the alpha1,3-Gal-epitope in mutant swine may have salutatory effects on the primate platelet activation observed in these xenografts.  相似文献   
44.
PURPOSE: This analysis evaluates whether adjuvant chemotherapy can be recommended for high-risk, surgically-resected, adult-type non-rhabdomyosarcoma soft tissue sarcomas (NRSTS) within the new European Pediatric Soft Tissue Sarcoma Study Group (EpSSG) protocol. The Italian and German Cooperative Groups reviewed their data-bases, analyzing patients classified as group I-II, with high-grade tumor (G3) larger than 5 cm in size. METHODS: The analysis included 36 patients, and compared the clinical features and outcome of the group of 21 patients who received chemotherapy versus the group of 15 patients treated with local therapies only. RESULTS: For the series as a whole, 5-year event-free survival (EFS), metastasis-free survival (MFS), and overall survival (OS) were 26.2%, 34.0%, and 37.5%, respectively. In patients treated with chemotherapy, MFS and OS were 49.5% and 41.5% (median time to relapse: 13 months). In patients who did not receive chemotherapy, MFS and OS were 0% and 23.8% (median time to relapse: 3 months). CONCLUSION: The role of adjuvant chemotherapy in NRSTS is still uncertain, however, the current retrospective analysis showed that: (1) despite the globally good prognosis of grossly-resected cases, patients with G3 and large-size have a high-risk of metastatic spread, and (2) MFS appears to be better in patients who had chemotherapy. Based in part on these results, and in accordance with recent suggestions coming from the literature on adult sarcomas, the EpSSG NRSTS protocol will recommend adjuvant chemotherapy in high-risk surgically-resected patients.  相似文献   
45.
BACKGROUND: Despite major surgical and medical advances, it is still a challenge to perform transplantation in small infants. This study, focusing on short- and long-term outcomes, summarizes our 10-year experience with liver transplantation (LTx) in infants aged less than 6 months. PATIENTS AND METHODS: We analyzed 43 patients aged 6 months or less (range: 12-184 days, median: 136 days) whose median weight at the time of LTx was 5.8 kg (range: 2.8-8.0 kg). The reasons for LTx were biliary atresia (n=27; 62.8%), neonatal hepatitis (n=6; 14%), neonatal cholestasis (n=4; 9.3%), and miscellaneous (n=6; 14%). The patients were followed up for a median time of 3 years and evaluated with respect to graft function, physical, and neurodevelopmental outcome. RESULTS: The patient survival was 90.7% after 1 year and 87.2% after 2 years. The graft survival was 86% after 1 year and 82.1% after 2 years. Twelve patients (27.9%) experienced 15 surgical complications requiring intervention, two of whom demonstrated vascular thrombosis (4.7%). Acute early rejection occurred in 15 patients (34.9%), and chronic rejection occurred in 3 patients (7%); 83.3% of the patients had normal liver function test results at the time of evaluation. Complications such as posttransplant lymphoproliferative disease (4.7%) and persistent arterial hypertension (4.7%) were rarely seen. The physical and neurodevelopmental outcomes were good. CONCLUSIONS: LTx in infants aged less than 6 months provides excellent short- and long-term results. Low weight or young age of infants awaiting LTx should not be exclusion criteria for LTx.  相似文献   
46.
1. Openers of ATP-sensitive K(+) channels are of interest in several therapeutic indications including overactive bladder and other lower urinary tract disorders. This study reports on the in vitro and in vivo characterization of a structurally novel naphthylamide N-[2-(2,2,2-trifluoro-1-hydroxy-1-trifluoromethyl-ethyl)-naphthalen-1-yl]-acetamide (A-151892), as an opener of the ATP-sensitive potassium channels. 2. A-151892 was found to be a potent and efficacious potassium channel opener (KCO) as assessed by glibenclamide-sensitive whole-cell current and fluorescence-based membrane potential responses (-log EC(50)=7.63) in guinea-pig bladder smooth muscle cells. 3. Evidence for direct interaction with KCO binding sites was derived from displacement of binding of the 1,4-dihydropyridine opener [(125)I]A-312110. A-151892 displaced [(125)I]A-312110 binding to bladder membranes with a -log Ki value of 7.45, but lacked affinity against over 70 neurotransmitter receptor and ion channel binding sites. 4. In pig bladder strips, A-151892 suppressed phasic, carbachol-evoked and electrical field stimulus-evoked contractility in a glibenclamide-reversible manner with -log IC(50) values of 8.07, 7.33 and 7.02 respectively, comparable to that of the potencies of the prototypical cyanoguanidine KCO, P1075. The potencies to suppress contractions in thoracic aorta (-log IC(50)=7.81) and portal vein (-log IC(50)=7.98) were not substantially different from those observed for suppression of phasic contractility of the bladder smooth muscle. 5. In vivo, A-151892 was found to potently suppress unstable bladder contractions in obstructed models of unstable contractions in both pigs and rats with pED(35%) values of 8.05 and 7.43, respectively. 6. These results demonstrate that naphthylamide analogs exemplified by A-151892 are novel K(ATP) channel openers and may serve as chemotypes to exploit additional analogs with potential for the treatment of overactive bladder and lower urinary tract symptoms.  相似文献   
47.
48.
The relationship between motor maps and cytoarchitectonic subdivisions in rat frontal cortex is not well understood. We use cytoarchitectonic analysis of microstimulation sites and intracellular stimulation of identified cells to develop a cell-based partitioning scheme of rat vibrissa motor cortex and adjacent areas. The results suggest that rat primary motor cortex (M1) is composed of three cytoarchitectonic areas, the agranular medial field (AGm), the agranular lateral field (AG1), and the cingulate area 1 (Cg1), each of which represents movements of different body parts. Vibrissa motor cortex corresponds entirely and for the most part exclusively to AGm. In area AG1 body/head movements can be evoked. In posterior area Cg1 periocular/eye movements and in anterior area Cg1 nose movements can be evoked. In all of these areas stimulation thresholds are very low, and together they form a complete representation of the rat's body surface. A strong myelinization and an expanded layer 5 characterize area AGm. We suggest that both the strong myelinization and the expanded layer 5 of area AGm may represent cytoarchitectonic specializations related to control of high-speed whisking behavior.  相似文献   
49.
Optimal adrenergic support in septic shock due to peritonitis   总被引:4,自引:0,他引:4  
BACKGROUND: The authors evaluated optimal adrenergic support using norepinephrine, dopamine, and dobutamine in a clinically relevant model of septic shock. METHODS: Twenty-eight mature, female, anesthetized sheep (weight, 30.5 +/- 3.6 kg) underwent cecal ligation and perforation and were randomized into four groups of seven animals to be treated with norepinephrine, dopamine-norepinephrine, dobutamine-norepinephrine, or no adrenergic agent. In all groups, lactated Ringer's solution was administered to restore cardiac filling pressures to baseline. In the norepinephrine group, norepinephrine (0.5-5 microg. kg(-1). min(-1)) was titrated to maintain mean arterial pressure between 75-85 mmHg. In the dopamine-norepinephrine group, dopamine was given first, and norepinephrine was added only when mean arterial pressure remained below 75 mmHg despite the infusion of 20 microg. kg(-1). min(-1) dopamine. In the dobutamine-norepinephrine group, dobutamine was started at the same time as norepinephrine and titrated up to 20 microg. kg(-1). min(-1) to get a 15% increase in cardiac output. RESULTS: The dobutamine-norepinephrine group had greater cardiac output; superior mesenteric blood flow, oxygen delivery (Do(2)), and oxygen consumption ([OV0312]o(2)); and lower blood lactate concentration and partial pressure of carbon dioxide (Pco(2)) gap than the controls did. Cumulative urine output was significantly higher in the dobutamine-norepinephrine group than in the other groups. Survival time was significantly longer in the dobutamine-norepinephrine (24 +/- 4 h), dopamine- norepinephrine (24 +/- 6 h), and norepinephrine (20 +/- 1 h) groups than the control group (17 +/- 2 h; P < 0.05 vs. other groups), and significantly longer in the combined dopamine-norepinephrine and dobutamine-norepinephrine groups (24 +/- 5 h) than in the norepinephrine alone group (P < 0.05). Histologic examination of lung biopsies revealed less severe lesions in the dobutamine-norepinephrine group than in the control and norepinephrine alone groups. Anatomic alterations in the lung, liver, and small intestine were less severe in the dobutamine-norepinephrine group than in the other groups. CONCLUSIONS: In this prolonged septic shock model, association of norepinephrine with either dopamine or dobutamine resulted in the longest survival and the least severe pulmonary lesions. The combination of dobutamine with norepinephrine was associated with a better myocardial performance, greater Do(2) and [OV0312]o(2), lower blood lactate concentration and Pco(2) gap, and less anatomic injury.  相似文献   
50.
BACKGROUND: Chylomicron-bound LPS (CM-LPS) renders hepatocytes unresponsive to stimulation by proinflammatory cytokines, a process termed cytokine tolerance. We have shown that cytokine tolerance is a time- and dose-dependent process requiring functional low-density lipoprotein receptors (LDLR). Thus, we hypothesized that cytokine tolerance directly correlates with the internalization of CM-LPS complexes, and inhibition of lipoprotein binding and/or internalization inhibits the induction of cytokine tolerance in hepatocytes. MATERIALS AND METHODS: We correlated the rate of internalization of radioiodinated CM-LPS complexes with hepatocellular NO production as a measure of cytokine responsiveness. In additional studies, we used four different strategies to inhibit binding/internalization of CM-LPS via LDLR and then determined the effect of each strategy on the induction of cytokine tolerance. RESULTS: There was a strong inverse correlation between the internalization of CM-LPS and the responsiveness of hepatocytes to proinflammatory cytokines (r(2) = -0.997). Furthermore, the greater the degree of LDLR inhibition, the less susceptible hepatocytes were to the induction of cytokine tolerance by CM-bound LPS. Accordingly, cytokine tolerance induction was inhibited in hepatocytes with decreased membrane expression of LDLR as compared to control cells (69 versus 12% control; P = 0.005). Competitive inhibition of CM-LPS binding prevented internalization of CM-LPS and resulted in loss of the cytokine-tolerant phenotype. Whereas CM-LPS successfully induced cytokine tolerance in ldlr(-/-) hepatocytes, it only occurred after a prolonged pretreatment period of 8 h. CM-LPS complexes containing apolipoprotein (apo) E(2) also required a prolonged pretreatment period to induce a level of cytokine tolerance comparable to that induced by CM-LPS complexes containing either apo E(3) or E(4). CONCLUSION: Lipoprotein-bound LPS inhibits the responsiveness of hepatocytes to proinflammatory cytokines in a manner directly correlated with the internalization of LPS. Furthermore, inhibition of lipoprotein binding/internalization prevents this LPS-mediated induction of cytokine tolerance in rodent hepatocytes.  相似文献   
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