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411.
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Introduction

Malignant pleural mesothelioma (MPM) has limited treatment options and a poor outcome. Programmed death 1/programmed death ligand 1 (PD-L1) checkpoint inhibitors have proven efficacious in several cancer types. Nivolumab is a fully humanized monoclonal antibody against programmed death 1 with a favorable toxicity profile. In MPM, the immune system is considered to play an important role. We therefore tested nivolumab in recurrent MPM.

Methods

In this single-center trial, patients with MPM received nivolumab 3 mg/kg intravenously every 2 weeks. Primary endpoint was the disease control rate at 12 weeks. Pre- and on-treatment biopsy specimens were obtained to analyze biomarkers for response.

Results

Of the 34 patients included, 8 patients (24%) had a partial response at 12 weeks and another 8 had stable disease resulting in a disease control rate at 12 weeks of 47%. One reached a partial response at 18 weeks. In 4 patients with stable disease, the tumor remained stable for more than 6 months. Treatment-related adverse events of any grade occurred in 26 patients (76%), most commonly fatigue (29%) and pruritus (15%). Grades 3 and 4 treatment-related adverse events were reported in 9 patients (26%), with pneumonitis, gastrointestinal disorders, and laboratory disorders mostly seen. One treatment-related death was due to pneumonitis and probably initiated by concurrent amiodarone therapy. PD-L1 was expressed on tumor cells in nine samples (27%), but did not correlate with outcome.

Conclusions

Single-agent nivolumab has meaningful clinical efficacy and a manageable safety profile in pre-treated patients with mesothelioma. PD-L1 expression does not predict for response in this population.  相似文献   
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Abstract: The clinical details are reported of two premature infants who developed late onset haemorrhagic disease after receiving their initial doses of vitamin K1 prophylaxis intravenously. Both reported infants had received two doses of intravenous vitamin K1, 0.1 mg, in the 1st week of life, and a further oral dose, 1.0 mg, at 4 weeks. Bleeding due to vitamin K deficiency occurred on days 74 and 84, respectively. Vitamin K deficiency bleeding is rare in low birthweight infants, probably because it has been routine practice to give such infants intramuscular vitamin K1. One of the reported infants had cytomegalovirus hepatitis, the other did not have liver disease. These findings could be explained if intramuscular vitamin K1 were to have a longer duration of effect than intravenous vitamin K1. This may be because intramuscular vitamin K1 acts as a depot preparation. The findings suggest that intravenous vitamin K1 is less effective than intramuscular for long-term prophylaxis against late onset haemorrhagic disease. Intravenous vitamin K1 should not be used for long-term prophylaxis in the prevention of late onset haemorrhagic disease.  相似文献   
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PURPOSE: Cisplatin (DDP)-resistant cells commonly exhibit reduced drug accumulation. Previous studies have shown that the major copper (Cu) influx transporter CTR1 controls the uptake of DDP in yeast and mammalian cells. The goal of this study was to examine the effect of Cu and DDP on the level and subcellular localization of hCTR1 protein in human ovarian carcinoma cells. EXPERIMENTAL DESIGN: Cultured human ovarian carcinoma A2780 cells were exposed to DDP and Cu, and the effect on hCTR1 was determined using Western blot analysis and confocal digital deconvolution microscopy. RESULTS: Loss of hCTR1 was triggered by DDP exposure in a concentration and time-dependent manner. Exposure to 0.5 micromol/L DDP for 5 minutes reduced hCTR1 levels and exposure to DDP concentrations > or =2 micromol/L caused almost complete disappearance. The loss of hCTR1 was observed within 1 minute of the start of exposure to 2 micromol/L DDP. Treatment of cells with 100 micromol/L Cu for 5 minutes produced a smaller effect. Pretreatment of cells with 2 micromol/L DDP for 5 minutes resulted in a 50% decrease in 64Cu uptake, demonstrating that the DDP-induced loss of hCTR1 detected by Western blot analysis and imaging was functionally significant. CONCLUSIONS: DDP down-regulated the amount of its major influx transporter in cultured human ovarian carcinoma cells in a concentration- and time-dependent manner. The effect was observed at DDP concentrations within the range found in the plasma of patients being treated with DDP, and it occurred very quickly relative to the half-life of the drug.  相似文献   
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The clinical application of 3D proton spectroscopic imaging (3D SI) of the human prostate requires a robust suppression of periprostatic lipid signal contamination, minimal intervoxel signal contamination, and the shortest possible measurement time. In this work, a weighted elliptical sampling of k-space, combined with k-space filtering and pulse repetition time (TR) reduction minimized lipid signals, intervoxel contamination, and measurement time. At 1.5 T, the MR-visible prostate metabolites citrate, creatine, and choline can now be mapped over the entire human prostate with uncontaminated spherical voxels, with a volume down to 0.37 cm3, in measurement times of 7-15 min.  相似文献   
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Proton MR spectroscopic imaging ((1)H-MRSI) of the human prostate, which has an interesting clinical potential, may be improved by increasing the magnetic field strength from 1.5T to 3T. Both theoretical and practical considerations are necessary to optimize the pulse timing for spectroscopic imaging of the human prostate at 3T. For in vivo detection of the strongly coupled spin system of citrate, not only should the spectral shape of the signal be easy to identify, but the timing used should produce MR signals at reasonably short echo times (TEs). In this study the spectral shape of the methylene protons of citrate was simulated with density matrix calculations and checked with phantom measurements. Different calculated optimal spectral shapes were measured in patients with prostate cancer with a 2D spectroscopic imaging sequence. T(1) and T(2) relaxation times were calculated for citrate and choline, the two major metabolites of interest in the prostate. We conclude that the optimum timing for in vivo point-resolved spectroscopy (PRESS) imaging at 3T is an interpulse timing sequence of 90 degrees-25 ms-180 degrees- 37.5 ms-180 degrees-12.5 ms-echo. A short repetition time (TR) of 750 ms partially saturates choline signals, but increases the SNR per unit time for citrate, and accommodates a maximum number of weighted averages of an elliptically sampled k-space for accurate localization and minimal contamination of the individual spectra. This is illustrated by means of a 3D spectroscopic imaging experiment in a complete prostate in vivo.  相似文献   
420.
继发于胃肠道癌的卵巢转移性癌称作Krukenberg瘤,而表现为Krukenberg瘤的胰腺癌卵巢转移病例尚属罕见,本文报道1例表现为Krukenberg瘤的胰腺癌卵巢转移病例.  相似文献   
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