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Background Post hoc analyses assessed the prognostic and predictive value of baseline alpha-fetoprotein (AFP), as well as clinical outcomes by AFP response or progression, during treatment in two placebo-controlled trials (REACH, REACH-2).Methods Serum AFP was measured at baseline and every three cycles. The prognostic and predictive value of baseline AFP was assessed by Cox regression models and Subpopulation Treatment Effect Pattern Plot method. Associations between AFP (≥ 20% increase) and radiographic progression and efficacy were assessed.Results Baseline AFP was confirmed as a continuous (REACH, REACH-2; p < 0.0001) and dichotomous (≥400 vs. <400 ng/ml; REACH, p < 0.01) prognostic factor, and was predictive for ramucirumab survival benefit in REACH (p = 0.0042 continuous; p < 0.0001 dichotomous). Time to AFP (hazard ratio [HR] 0.513; p < 0.0001) and radiographic (HR 0.549; p < 0.0001) progression favoured ramucirumab. Association between AFP and radiographic progression was shown for up to 6 (odds ratio [OR] 5.1; p < 0.0001) and 6–12 weeks (OR 1.8; p = 0.0065). AFP response was higher with ramucirumab vs. placebo (p < 0.0001). Survival was longer in patients with an AFP response than patients without (13.6 vs. 5.6 months, HR 0.451; 95% confidence interval, 0.354–0.574; p < 0.0001).Conclusions AFP is an important prognostic factor and a predictive biomarker for ramucirumab survival benefit. AFP ≥ 400 ng/ml is an appropriate selection criterion for ramucirumab.Clinical Trial Registration ClinicalTrials.gov, REACH (NCT01140347) and REACH-2 (NCT02435433).Subject terms: Oncology, Biomarkers  相似文献   
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BACKGROUND: The combined treatment of sustained-release basic fibroblast growth factor (Sr-bFGF) and a 5-hydroxytryptamine(2A) blocker, sarpogrelate, was evaluated to see whether it reversed the impaired collateral circulation in diabetic (DM) mouse hindlimb ischemia. METHOD AND RESULTS: Diabetic and normal mice with ischemic hindlimb were randomly assigned to 1 of 5 experimental groups (no treatment, sarpogrelate 50 mg . kg(-1) . day(-1), 20 microg or 50 microg Sr-bFGF and a combined treatment of 20 microg Sr-bFGF and sarpogrelate), and treated for 4 weeks. Tissue blood perfusion (TBP), vascular density (angiogenesis) and the number of mature vessels (arteriogenesis) were checked by the use of standard methods. Although angiogenesis was comparable (161+/-14 vs 154+/-12 vessels/mm(2)), the laser Doppler perfusion image index (LDPII) (0.43+/-0.11 (SD) vs 0.63+/-0.08, p<0.05) and arteriogenesis (8+/-3 vs 12+/-4 vessels/mm(2), p<0.05) were significantly lower in DM mice than those in normal mice. The dose of Sr-bFGF for the sufficient number of mature vessels (>or=45 vessels/mm(2)) and LDPII (>or=0.9) was 20 microg for the normal mice, and 50 microg for the DM mice, which was reduced with the aid of sarpogrelate. Conclusions A combined therapy of Sr-bFGF and sarpogrelate is effective for neovascularization to reverse the impaired arteriogenesis and TBP in DM mice.  相似文献   
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Omeprazole markedly inhibits basal and stimulated gastric acid secretion and has the ability to produce hypergastrinemia and hyperplasia of enterochromaffin-like cells in humans. On the other hand, paunotol, an acyclic diterpene alcohol, has been reported to inhibit gastrin release by stimulating endogenous secretin release. We investigated the effect of plaunotol on serum gastrin levels after six to eight weeks of omeprazole (20 mg/day) administration in 22 patients (16 males, 6 females; mean age 52.3, range 36–70 years) with peptic ulcer disease. The patients were randomized to the following two groups: 11 subjects with omerprazole alone (single group) and 11 with omeprazole plus plaunotol (240 mg/day) (combination group) treatment. There were no significant differences between the two groups concerning age, sex, ulcer stage, ulcer history, environmental factors, andHelicobacter pylori (HP) prevalence. After complete drug(s) administration, serum immunoreactive (ir) -gastrin levels increased significantly in the single group (P<0.001) in contrast to the combination group, and plaunotol significantly inhibited hypergastrinemia induced by omeprazole administration (P<0.001). Significant increases in serum ir-calcitonin gene-related peptide concentrations were observed in the combination group compared to the single group (P<0.05). However, there were no significant changes in serum ir-secretin, somatostatin, and vasoactive intestinal polypeptide levels as well as ulcer healing and HP prevalence between the two groups. These findings suggest that plaunotol may suppress hypergastrinemia induced by long-term omeprazole administration, at least partly, via a certain brain-gut hormone affecting gastrin release.  相似文献   
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The liver has been considered as a tolerogenic organ in the sense that favors the induction of peripheral tolerance. The administration of antigens (Ags) via the portal vein causes tolerance, which is termed portal vein tolerance and can explain the occurrence of tolerogenic responses in the liver. Here we discuss the fundamental mechanisms accounting for portal vein tolerance. Antigen-presenting cells (APCs) in the liver, especially dendritic cells and sinusoidal endothelial cells, have limited the ability to produce pro-inflammatory cytokines upon stimulation with endotoxin, an effect that could be due to the continuous exposure to bacterial Ags derived from intestinal microflora. Ag presentation by liver APCs results in T cell tolerance through clonal deletion and selection of regulatory T cells. Thus, APCs with immunosuppressive functions are associated with the achievement of portal vein tolerance via the induction of clonal deletion and generation of regulatory T cells.  相似文献   
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