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101.
PURPOSE: In the present study, we investigated the degree of protein expression and gene amplification of HER-2 in esophageal squamous cell carcinoma (SCC) cell lines and freshly isolated tumors, and trastuzumab-mediated biological activity, in particular antibody-dependent cellular cytotoxicity (ADCC) against HER-2-expressing esophageal SCC cell lines. EXPERIMENTAL DESIGN: Ten different SCC cell lines with various levels of HER-2 status evaluated by flow cytometry, immunocytochemistry (HercepTest), and fluorescence in situ hybridization were evaluated for ADCC, growth inhibitory, or apoptosis-inducing activities mediated by trastuzumab. RESULTS: Trastuzumab induced ADCC against HER-2-expressing esophageal SCC and the activities reflected the degree of HER-2 expression analyzed by flow cytometric analysis, but not by HercepTest nor fluorescence in situ hybridization analysis. Furthermore, trastuzumab-mediated ADCC against transforming growth factor-beta-producing SCC was enhanced by the treatment with SB-431542, which is a selective inhibitor of the phosphorylation induced by transforming growth factor-beta. There were very marginal effects of anti-proliferative or apoptosis-inducing activities mediated by trastuzumab for HER-2-expressing esophageal SCC. CONCLUSION: HER-2-expressing esophageal SCC cells could be killed by trastuzumab-mediated ADCC and the activity reflected the degree of HER-2 expression detected by flow cytometry.  相似文献   
102.
A 49-yr-old Japanese woman underwent upper gastrointestinal endoscopy because of nonspecific dyspepsia. Endoscopy revealed a flat elevated lesion about 15 mm in diameter adjacent to the duodenal papilla, the surface of which was uneven and covered with whitish granules. Based on the results of histological examination with immunohistochemistry (positive for CD10, CD20, CD79a, and bcl-2 protein, negative for CD5 and cyclin D1), a diagnosis of grade 1/3 follicular lymphoma was established. Systemic staging examinations suggested the lymphoma was restricted to the mucosa and superficial portion of the submucosa in the duodenal wall. The patient was treated with a combination of CHOP chemotherapy (cyclophosphamide, doxorubicin, vincristine, and prednisolone) and monoclonal anti-CD20 antibody (rituximab), in addition to radiotherapy. After six courses of this combination chemotherapy, complete regression of the lymphoma was observed. Although reports of small duodenal lymphoma (<20 mm or localized to the mucosa or submucosa) are extremely rare, the features of this case are characteristic of small duodenal lymphoma in terms of evolution around the ampulla of Vater, low-grade follicular type, occurrence in a women, occurrence in the fourth decade of life, and favorable outcome, and this type of tumor may need to be distinguished by pathogenesis and clinical behavior from various other gastrointestinal lymphomas.  相似文献   
103.
There is a concern on the part of public health community that adverse health consequences by thimerosal, a preservative in vaccines for infants, may occur among infants during immunization schedule. Therefore, the effect of thimerosal on cellular content of glutathione was examined on thymocytes obtained from 4-week-old rats using a flow cytometer and 5-chloromethylfluorescein diacetate. Thimerosal at concentrations ranging from 1 to 10 microM reduced the cellular content of glutathione in a concentration-dependent manner, and the complete depletion of cellular glutathione was observed when the cells were treated with 30 microM thimerosal. L-Cysteine significantly attenuated the actions of thimerosal to reduce the glutathione content and to increase the intracellular Ca2+ concentration. Prolonged incubation (24 h) with 1-3 microM thimerosal induced the apoptosis. The cytotoxic action of thimerosal was greatly augmented when the cells suffered oxidative stress induced by H2O2. It may be unlikely that thimerosal exerts potent cytotoxic action under the in vivo condition because the blood concentration of thimerosal after receiving vaccines does not seem to reach micromolar range and nonprotein thiols at micromolar concentrations are present in the blood.  相似文献   
104.
Oncolytic viruses are a promising method of cancer therapy, even for advanced malignancies. HF10, a spontaneously mutated herpes simplex type 1, is a potent oncolytic agent. The interaction of oncolytic herpes viruses with the tumor microenvironment has not been well characterized. We injected HF10 into tumors of patients with recurrent breast carcinoma, and sought to determine its effects on the tumor microenvironment. Six patients with recurrent breast cancer were recruited to the study. Tumors were divided into two groups: saline-injected (control) and HF10-injected (treatment). We investigated several parameters including neovascularization (CD31) and tumor lymphocyte infiltration (CD8, CD4), determined by immunohistochemistry, and apoptosis, determined by terminal deoxynucleotidyl transferase dUTP nick end labeling assay. Median apoptotic cell count was lower in the treatment group (P=0.016). Angiogenesis was significantly higher in treatment group (P=0.032). Count of CD8-positive lymphocytes infiltrating the tumors was higher in the treatment group (P=0.008). We were unable to determine CD4-positive lymphocyte infiltration. An effective oncolytic viral agent must replicate efficiently in tumor cells, leading to higher viral counts, in order to aid viral penetration. HF10 seems to meet this criterion; furthermore, it induces potent antitumor immunity. The increase in angiogenesis may be due to either viral replication or the inflammatory response.  相似文献   
105.
We describe a patient with acute lymphoblastic leukemia (ALL, L2) who relapsed with multiple bone lesions after allogeneic bone marrow transplantation (allo-BMT). Allo-BMT was performed from an HLA-identical sibling during the first hematological complete remission (CR). Minimal residual disease (MRD) assessed by polymerase chain reaction (PCR) with primers for T cell receptor delta (TCRdelta) gene became positive in the bone marrow sample on day 46 after allo-BMT. On day 113, the patient complained of a painful tumor at the right clavicle. The examination of biopsy specimen revealed infiltration of leukemic cells. After partial response was achieved by local radiotherapy, disseminated bone lesions were demonstrated by 99mTC scintigraphy scan, followed by bone marrow relapse on day 137. The patient died of cardiac tamponade on day 236 after Allo-BMT. MRD assessed by PCR assay for TCRdelta gene in the bone marrow is useful for the prediction of extramedullary as well as medullary relapse after BMT.  相似文献   
106.
Polycomb repressive complex 2 (PRC2) methylates histone H3 lysine 27 and represses gene expression to regulate cell proliferation and differentiation. Enhancer of zeste homolog 2 (EZH2) or its close homolog EZH1 functions as a catalytic subunit of PRC2, so there are two PRC2 complexes containing either EZH2 or EZH1. Tumorigenic functions of EZH2 and its synthetic lethality with some subunits of SWItch/Sucrose Non‐Fermentable (SWI/SNF) chromatin remodeling complexes have been observed. However, little is known about the function of EZH1 in tumorigenesis. Herein, we developed novel, orally bioavailable EZH1/2 dual inhibitors that strongly and selectively inhibited methyltransferase activity of both EZH2 and EZH1. EZH1/2 dual inhibitors suppressed trimethylation of histone H3 lysine 27 in cells more than EZH2 selective inhibitors. They also showed greater antitumor efficacy than EZH2 selective inhibitor in vitro and in vivo against diffuse large B‐cell lymphoma cells harboring gain‐of‐function mutation in EZH2. A hematological cancer panel assay indicated that EZH1/2 dual inhibitor has efficacy against some lymphomas, multiple myeloma, and leukemia with fusion genes such as MLL‐AF9, MLL‐AF4, and AML1‐ETO. A solid cancer panel assay demonstrated that some cancer cell lines are sensitive to EZH1/2 dual inhibitor in vitro and in vivo. No clear correlation was detected between sensitivity to EZH1/2 dual inhibitor and SWI/SNF mutations, with a few exceptions. Severe toxicity was not seen in rats treated with EZH1/2 dual inhibitor for 14 days at drug levels higher than those used in the antitumor study. Our results indicate the possibility of EZH1/2 dual inhibitors for clinical applications.  相似文献   
107.
BACKGROUND AND OBJECTIVES: Hepatocellular carcinoma (HCC) is one of the most common recurrence diseases, which affects the patient's prognosis. The aim of this report is to evaluate recurrence risk after primary treatment by the combination study with the clinical features and immunohistological findings. METHODS: 153 removable HCCs were examined by immunohistochemical study of the proliferating cell nuclear antigen (PCNA), p53, or Bax. The relationships of these factors with histological grades, the presence of intra-hepatic metastasis (IM), tumor size, value of serum alpha-fetoprotein (AFP), and prognosis were studied. PCNA labeling index (LI) was calculated to count positive nuclei in 1,000 cells. RESULTS: PCNALI was significantly higher in cancer and correlated with tumor size. PCNALI and the tumor diameter in themselves could be a good predictor for patient prognosis and the combination study of them was an even stronger indicator. The value of AFP was significantly higher in positive p53 cases. The incidence of p53 was associated with histological types. The presence of IM was found in negative Bax cases of main tumors. The appearance of Bax was not correlated with histological types. The incidence of p53 or Bax was indicated to distinguish the patient prognosis of the lower grade histological cases, in which differences could not be found by the routine histological study. CONCLUSIONS: The combination study of the immunohistochemical findings and the clinical features could be one of the most important aids in interpreting the status of HCC.  相似文献   
108.
BACKGROUND: Peripheral blood stem cell (PBSC) reinfusion has been widely used for hematopoietic reconstitution after high-dose chemotherapy. However, the optimal dose of granulocyte colony-stimulating factor (G-CSF) for PBSC mobilization in combination with chemotherapy for autograft remains unknown. METHODS: To find the optimal dose of glycosylated G-CSF (lenograstim) for PBSC mobilization in combination with chemotherapy for aggressive non-Hodgkin's lymphoma (NHL), we conducted a dose-finding study on 43 newly diagnosed patients who had unfavorable prognostic factors. They received four to six courses of cyclophosphamide, doxorubicin, vincristine and prednisolone combined with lenograstim every 2 weeks (biweekly CHOP therapy). PBSC apheresis was started after the third course of biweekly CHOP therapy. Lenograstim was given daily from day 3 until the day of the last apheresis. The optimum dose of lenograstim was assessed based on mobilization efficacy and safety profiles at a daily single dose of 2, 5 and 10 microg/kg for eight patients in each level. RESULTS: The collected number of CD34+ cells in the first apheresis products was higher in the 5 microg/kg group than in the 2 microg/kg group (median, 4.22 x 10(6) vs 2.49 x 10(6) CD34+ cells/kg, P = 0.051). The highest dose of 10 microg/kg (median, 2.99 x 10(6) CD34+ cells/kg) failed to show a dose dependence in PBSC mobilization. The efficacy and safety of the 5 microg/kg dose were further confirmed in an additional 19 patients. CONCLUSIONS: The present study suggests that the recommended dose of lenograstim for PBSC mobilization with CHOP therapy in untreated NHL is 5 microg/kg.  相似文献   
109.
Intravenous use of contrast medium (CM), which may cause kidney dysfunction, is admissible for hemodialysis patients because of the efficient removal by hemodialysis. We herein report a 61-year-old woman on hemodialysis who suffered from cholecystitis and cholangitis after large-volume CM administration during continuous renal replacement therapy. After catheter ablation, she developed life-threatening retroperitoneal hemorrhage, which led to the use of 500 mL CM for 5 consecutive days. It should be kept in mind that excessive vicarious CM excretion in the biliary system may become a predisposing factor of cholecystitis and cholangitis in patients who frequently undergo radiological interventions and imaging.  相似文献   
110.
PURPOSEThe aim of this study was to assess the usefulness of denoising deep-learning-based reconstruction (dDLR) to improve image quality and vessel delineation in noncontrast 3-T whole-heart coronary magnetic resonance angiography (WHCMRA) with sub-millimeter isotropic resolution (Sub-mm) compared with a standard resolution without dDLR (Standard).METHODSFor 10 healthy volunteers, we acquired the WHCMRA with Sub-mm with and without dDLR and Standard to quantify signal- (SNR) and contrast-to-noise ratio (CNR) and vessel edge signal response (VESR) in all the 3 image types. Two independent readers subjectively graded vessel sharpness and signal homogeneity of 8 coronary segments in each patient. We used Kruskal–Wallis test with Bonferroni correction to compare SNR, CNR, VESR, and the subjective evaluation scores among the 3 image types and weighted kappa test to evaluate inter-reader agreement on the scores.RESULTSSNR was significantly higher with Sub-mm with dDLR (P < .001) and Standard (P = .005) than with Sub-mm without dDLR and was comparable between Sub-mm with dDLR and Standard (P = .511). CNR was significantly higher with Sub-mm with dDLR (P < .001) and Standard (P = .005) than with Sub-mm without dDLR and was comparable between Sub-mm with dDLR and Standard (P = .560). VESR was significantly greater with Sub-mm with (P = .001) and without dDLR (P = .017) than with Standard and was comparable between Sub-mm with and without dDLR (P = 1.000). In the proximal, middle, distal, and all the coronary segments, the subjective vessel sharpness was significantly better with Sub-mm with dDLR than Sub-mm without dDLR and Standard (P < .001, for all) and was comparable between Sub-mm without dDLR and Standard (P > .05); the subjective signal homogeneity was significantly improved from Sub-mm without dDLR to Standard to Sub-mm with dDLR (P < .001). The inter-reader agreement was excellent (kappa = 0.84).CONCLUSIONApplication of dDLR is useful for improving image quality and vessel delineation in the WHCMRA with Sub-mm compared with Standard.

Main points
  • A denoising method with deep-learning-based reconstruction (dDLR) uses a deep convolution neural network to reduce image noise in magnetic resonance images without additional scan time.
  • dDLR can be applied to improve signal- (SNR) and contrast-noise ratio in noncontrast 3-T whole-heart coronary magnetic resonance angiography (WHCMRA) using a spoiled gradient-echo sequence, which offers lower SNR than a steady-state free precession sequence commonly applied at 1.5 T.
  • Combined application of dDLR and sub-millimeter isotropic resolution is useful for improving vessel sharpness, signal homogeneity, and delineation of the coronary arteries in the WHCMRA.
Three-dimensional (3D) whole-heart coronary magnetic resonance angiography (WHCMRA) is a noninvasive imaging method for assessing coronary artery stenosis and is advantageous over coronary computed tomography angiography (CCTA) because it does not require radiation exposure or contrast media administration and is only slightly susceptible to calcium-related artifacts.1-3 Because WHCMRA is commonly limited in delineation of distal coronary segments and quantification of vessel lumen stenosis due to its insufficient spatial resolution and anisotropy, some investigators have used various techniques to acquire WHCMRA with sub-millimeter isotropic resolution (Sub-mm) whose image quality is not necessarily satisfactory at 1.5 T, within an acceptable acquisition time.4-6 While a steady-state free precession (SSFP) sequence has been commonly applied in noncontrast WHCMRA at 1.5 T, increased B1 field inhomogeneity, frequency offset from tissue susceptibility variation, and specific absorption rate limit consistency of SSFP at 3 T. As such, the spoiled gradient-echo sequence, which decreases the signal-to-noise ratio (SNR) of the coronary arteries, has often been used at 3 T.7-10A 3-T clinical MR scanner with a maximum gradient magnetic field of 100 mT/m (the slew rate: 200 mT/m/ms) has been recently introduced and can offer thinner slice images at the same bandwidth (i.e., the same sampling interval/time). With this scanner, a denoising method with deep-learning-based reconstruction (dDLR) has been newly developed using a convolution neural network (CNN) to improve SNR in high-resolution MR images without additional scan time.11 Currently, this dDLR algorithm (Advanced intelligent Clear-IQ Engine [AiCE], Canon Medical Systems Corporation) is clinically available only from the single vendor. While some smoothing filters frequently applied in clinical settings are designed to reduce high-frequency noise at the cost of image blurring, we hypothesized that dDLR should only reduce image noise without any negative influence on the delineation of the coronary vessels in WHCMRA. Thus, we performed volunteer studies to assess usefulness of dDLR to improve image quality and coronary vessel delineation in noncontrast WHCMRA with Sub-mm compared with a standard resolution without dDLR (Standard) using this 3-T scanner.  相似文献   
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