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101.
PURPOSE: Ifosfamide, carboplatin, etoposide, and vincristine, alone and in combination, are highly active against small-cell lung cancer (SCLC). This trial was designed to investigate whether survival could be improved by a regimen of all four drugs (ICE-V) compared with standard chemotherapy in patients with SCLC and good performance status, and to assess the patients' quality of life (QL). PATIENTS AND METHODS: Patients were randomly assigned to receive six cycles of either ICE-V at 4-week intervals without dose reduction or standard chemotherapy administered according to local practice. The recommended standard control regimens were cyclophosphamide, doxorubicin, and etoposide; and cisplatin and etoposide. RESULTS: A total of 402 patients were randomly assigned, and 350 (87%) patients have died. Overall survival was longer in the ICE-V group (hazard ratio, 0.74; 95% CI, 0.60 to 0.91; P = .0049), median survival was 15.6 months in the ICE-V group and 11.6 months in the control group, and 2-year survival rates were 20% and 11%, respectively. There was no evidence that the relative survival benefit for ICE-V was less in extensive-stage than in limited-stage patients. An increased rate of septicemia was reported in the ICE-V group (15% v 7% in the control group), but this did not result in an increase in reported treatment-related deaths (four patients [2%] in both groups). The findings on QL were broadly similar in both groups, with some benefit in favor of ICE-V. CONCLUSION: Compared with standard chemotherapy, the ICE-V regimen improves overall survival without QL penalties, despite an increased but manageable level of toxicity.  相似文献   
102.
During drug discovery, it is important to optimise the affinity for the biomolecular target and also the properties of molecules that influence absorption, distribution, metabolism, excretion, and toxicity (ADMET). The goal is to improve the properties of a lead compound and select highly ‘developable’ candidates. Efficient pharmaceutical property profiling operations are now run in parallel to potency screening during lead optimization and provide data for compound prioritization and for the selection of compounds for in vivo studies. The main components of a profiling strategy suitable for early discovery are the measurement of selected physicochemical properties together with in vitro screening for metabolic stability. In addition, enzyme or cellular assays may be deployed for investigation of cellular permeability (including active and passive transport), plasma protein binding, toxicity, and the potential for drug-drug interactions. The four principal physicochemical parameters measured are lipophilicity, dissociation constant, permeability through artificial membranes, and aqueous solubility. An objective of property-based design is the identification of structure property relationships for ADMET that can suggest structural modifications that will also promote or retain high affinity for the biomolecular target. Sometimes this is not possible and new lead molecules may need to be identified to provide new starting points. A sub-optimal in vitro profile may be acceptable as long as there is a reasonable probability of achieving an adequate in vivo profile for clinical studies. In these cases, the application of composite models that can relate in vitro to in vivo behavior is important. Full ‘physiologically based pharmacokinetic’ (PBPK) models can be used; however, there are also simpler approaches available that may be adequate and more easily applied for ranking compounds within a series. Reliable in vitroin vivo correlation is still very difficult because of the multiplicity of mechanisms involved. For the future, there is a need to develop better criteria for making mechanistically based classifications to develop differentiated models that are appropriate for different types of compound. It is also difficult to correct models for non-specific binding of drugs to membranes and proteins and we need better lipophilicity measures for accurately estimating the affinity of drugs for tissues. PBPK modeling leads to the exciting concept of the ‘virtual human’; however, PBPK models suitable for drug discovery applications are still in their infancy and it will be some time before their promise is fulfilled.  相似文献   
103.
Cardiovascular (CV) toxicities of the Bruton tyrosine kinase (BTK) inhibitor ibrutinib may limit use of this effective therapy in patients with chronic lymphocytic leukemia (CLL). Acalabrutinib is a second-generation BTK inhibitor with greater BTK selectivity. This analysis characterizes pooled CV adverse events (AE) data in patients with CLL who received acalabrutinib monotherapy in clinical trials (clinicaltrials gov. Identifier: NCT02029443, NCT02475681, NCT02970318 and NCT02337829). Acalabrutinib was given orally at total daily doses of 100–400 mg, later switched to 100 mg twice daily, and continued until disease progression or toxicity. Data from 762 patients (median age: 67 years [range, 32–89]; median follow-up: 25.9 months [range, 0–58.5]) were analyzed. Cardiac AE of any grade were reported in 129 patients (17%; grade ≥3, n=37 [5%]) and led to treatment discontinuation in seven patients (1%). The most common any-grade cardiac AE were atrial fibrillation/flutter (5%), palpitations (3%), and tachycardia (2%). Overall, 91% of patients with cardiac AE had CV risk factors before acalabrutinib treatment. Among 38 patients with atrial fibrillation/flutter events, seven (18%) had prior history of arrhythmia or atrial fibrillation/flutter. Hypertension AE were reported in 67 patients (9%), 43 (64%) of whom had a preexisting history of hypertension; no patients discontinued treatment due to hypertension. No sudden cardiac deaths were reported. Overall, these data demonstrate a low incidence of new-onset cardiac AE with acalabrutinib in patients with CLL. Findings from the head-to-head, randomized trial of ibrutinib and acalabrutinib in patients with high-risk CLL (clinicaltrials gov. Identifier: NCT02477696) prospectively assess differences in CV toxicity between the two agents.  相似文献   
104.
ObjectiveOne of the primary tools in the assessment of individual‐level patient outcomes is Jacobson and Truax, (1991’s) Reliable Change Index (RCI). Recent efforts to optimize the RCI have revolved around three issues: (a) extending the RCI beyond two timepoints, (b) estimating the RCI using scale scores from item response theory or factor analysis and (c) estimation of person‐ and time‐specific standard errors of measurement.MethodWe present an adaptation of a two‐stage procedure, a measurement error‐corrected multilevel model, as a tool for RCI estimation (with accompanying Statistical Analysis System syntax). Using DASS‐21 data from a community‐based mental health center (N = 379), we illustrate the potential for the model as unifying framework for simultaneously addressing all three limitations in modeling individual‐level RCI estimates.ResultsCompared to the optimal‐fitting RCI model (moderated nonlinear factor analysis scoring with measurement error correction), an RCI model that uses DASS‐21 total scores produced errors in RCI inferences in 50.8% of patients; this was largely driven by overestimation of the proportion of patients with statistically significant improvement.ConclusionEstimation of the RCI can now be enhanced by the use of latent variables, person‐ and time‐specific measurement errors, and multiple timepoints.  相似文献   
105.
106.

Purpose

AZD3409 is a novel DPTI that has potent activity against both FTase and GGTase-1. The in vitro inhibition profile of AZD3409 was characterized using three different cell lines: mouse embryogenic fibroblasts, transfected with H-RasV12 (MEF), A549 cells (Ki4B-Ras mutation) and MCF-7 cells (no Ras mutation).

Methods

Both cytotoxicity and levels of inhibition of farnesylation and geranylgeranylation were determined in different assays in relation to the concentration of AZD3409. Results were compared with those obtained with the first-generation FTase inhibitor lonafarnib or the GGTase-1 inhibitor GGTI-2147.

Results

The mean IC50 for cytotoxicity of AZD3409 and lonafarnib was 510 and 15,200?nM in MEF cells, 10,600 and 2,740?nM in A549 cells and 6,170 and 9,490?nM in MCF7 cells, respectively. In these cells, the IC50 for FTase activity of AZD3409 ranged from 3.0 to 14.2?nM and of lonafarnib from 0.26 to 31.3?nM. The inhibiting activity of AZD3409 and lonafarnib on general protein farnesylation was comparable with the specific farnesylation levels of HDJ-2. In vitro geranylgeranylation of Rap1a could be inhibited by GGTI-2147 in all three cell lines, but only in MCF-7 cells by AZD3409. These results are in agreement with the IC50 values for GGTase-1 activity as the lowest IC50 for AZD3409 was found in the MCF-7 cell line.

Conclusions

AZD3409 inhibits farnesylation to a higher extent than geranylgeranylation. Both inhibition of farnesylation and geranylgeranylation could not be correlated to the antiproliferative activity of the drug.  相似文献   
107.
108.
109.
Obesity is a multifactorial disease and is associated with an increased risk of developing metabolic syndrome and co-morbidities. Dysregulated expansion of the adipose tissue during obesity induces local tissue hypoxia, altered secretory profile of adipokines, cytokines and chemokines, altered profile of local tissue inflammatory cells leading to the development of low-grade chronic inflammation. Low grade chronic inflammation is considered to be the underlying mechanism that increases the risk of developing obesity associated comorbidities. The glucocorticoid induced protein annexin A1 and its N-terminal peptides are anti-inflammatory mediators involved in resolving inflammation. The aim of the current study was to investigate the role of annexin A1 in obesity and associated inflammation. To achieve this aim, the current study analysed data from two feasibility studies in clinical populations: (1) bariatric surgery patients (Pre- and 3 months post-surgery) and (2) Lipodystrophy patients. Plasma annexin A1 levels were increased at 3-months post-surgery compared to pre-surgery (1.2 ± 0.1 ng/mL, n = 19 vs. 1.6 ± 0.1 ng/mL, n = 9, p = 0.009) and positively correlated with adiponectin (p = 0.009, r = 0.468, n = 25). Plasma annexin A1 levels were decreased in patients with lipodystrophy compared to BMI matched controls (0.2 ± 0.1 ng/mL, n = 9 vs. 0.97 ± 0.1 ng/mL, n = 30, p = 0.008), whereas CRP levels were significantly elevated (3.3 ± 1.0 µg/mL, n = 9 vs. 1.4 ± 0.3 µg/mL, n = 31, p = 0.0074). The roles of annexin A1 were explored using an in vitro cell based model (SGBS cells) mimicking the inflammatory status that is observed in obesity. Acute treatment with the annexin A1 N-terminal peptide, AC2-26 differentially regulated gene expression (including PPARA (2.8 ± 0.7-fold, p = 0.0303, n = 3), ADIPOQ (2.0 ± 0.3-fold, p = 0.0073, n = 3), LEP (0.6 ± 0.2-fold, p = 0.0400, n = 3), NAMPT (0.4 ± 0.1-fold, p = 0.0039, n = 3) and RETN (0.1 ± 0.03-fold, p < 0.0001, n = 3) in mature obesogenic adipocytes indicating that annexin A1 may play a protective role in obesity and inflammation. However, this effect may be overshadowed by the continued increase in systemic inflammation associated with rapid tissue expansion in obesity.  相似文献   
110.
IntroductionThe Bombay phenotype is a rare blood group determined by the absence of H antigens. Bombay individuals produce anti-H, a clinically significant antibody that react against all ABO blood group. Anti-H can mask underlying alloantibody during antibody investigation, a challenge in current transfusion practice. The aim of this article is to explore saliva inhibition, a novel method to detect underlying alloantibody in Bombay individuals.Case PresentationThe case is a 93-year-old female transfused with pre-donated autologous blood for a surgery. We determined anti-H subclass and thermal amplitude, secretor status, and optimal ratio of saliva and Bombay plasma. Plasma samples containing anti-H were spiked with anti-Fy(a) to determine the effectiveness of saliva inhibition in uncovering underlying alloantibodies.ResultsAnti-H was confirmed to be predominately IgM with broad thermal amplitude. Tube immediate spin (IS) showed stronger anti-H reactivity compared to column agglutination technology (CAT). Spiked anti-Fy(a) was successfully detected using saliva inhibition method.ConclusionTube IS appears more sensitive to anti-H. Saliva inhibition appears to be a promising method to detect underlying alloantibody in the plasma of Bombay phenotype individuals.  相似文献   
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