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81.
PURPOSE: The purpose of this work was to provide a scientific basis for specific immunotherapy of colon cancer. EXPERIMENTAL DESIGN: This study focused on identification of colon tumor-associated antigens and HLA-A2-restricted and tumor-reactive cytotoxic T lymphocytes (CTLs) generated from tumor-infiltrating lymphocytes of a colon cancer patient. A gene expression cloning method was used to identify genes coding for tumor antigens. Fifty-six peptides with HLA-A2-binding motifs encoded by these proteins were examined for their ability to induce HLA-A2-restricted and tumor-reactive CTLs. RESULTS: We identified the following three genes coding for proliferation-related proteins: thymidylate synthase (TYMS), which is involved in chemoresistance (5-fluorouracil); 5'-aminoimidazole-4-carboxamide-1-beta-d-ribonucleotide transfolmylase/inosinicase (AICRT/I); and phosphoglycerate kinase 1 (PKG1), which was secreted by tumor cells and involved in the angiogenic process. TYMS was preferentially expressed in tumor cells, whereas AICRT/I and PKG1 were equally expressed in both cancer cells and normal tissues at the mRNA level. Among 56 peptides with HLA-A2-binding motifs encoded by these proteins, 8 peptides were recognized by the CTLs, and 5 of 8 peptides were also recognized by the CTL precursors without ex vivo activation in the peripheral blood of colon cancer patients. Furthermore, four of them (one each from TYMS and PKG1 and two from AICRT/1) possessed the ability to induce HLA-A2-restricted and peptide-specific CTLs cytotoxic to colon tumor cells in peripheral blood mononuclear cells of colon cancer patients. CONCLUSIONS: TYMS and PGK1, as well as their epitope peptides, might be appropriate target molecules for specific immunotherapy of HLA-A2(+) colon cancer patients because of the positive role of TYMS and PGK1 in chemoresistance (5-fluorouracil) and angiogenesis of tumor cells, respectively.  相似文献   
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Three lipopeptides, ciliatamides A-C ( 1- 3), were isolated from the deep-sea sponge Aaptos ciliata, and their structures were elucidated on the basis of spectroscopic and chemical methods. Ciliatamides A ( 1) and B ( 2) were found to be antileishmanial, while 2 also exhibited marginal cytotoxicity to HeLa cells.  相似文献   
84.
Ovarian Sertoli-Leydig cell tumors (SLCT) are rare sex cord stromal neoplasms. To date there have been approximately 25 case reports of ovarian SLCT expressing alpha-fetoprotein (AFP). In such cases, AFP was immunohistochemically detected in the Sertoli cells, Leydig cells, or hepatocytes. This case report confirms heterologous gastrointestinal epithelium expression of AFP. A 20-year-old woman presented with complaints of abdominal enlargement and irregular menstrual cycles over one year. A right ovarian tumor was detected and the patient's serum AFP was elevated. A right salpingo-oophorectomy was performed. On microscopic examination, the tumor was composed of a fibrosarcoma-like area and a poorly differentiated SLCT area with heterologous gastrointestinal epithelium. Immunohistochemical analysis detected AFP in the gastrointestinal epithelium only. Postoperatively, serum AFP levels fell to normal. A recurrent tumor was discovered in the omentum after adjuvant chemotherapy, but serum AFP remained normal. A second laparotomy was performed and the recurrent tumor showed only fibrosarcoma-like features. The patient received second line chemotherapy and is currently in remission. This is the first case of AFP production by heterologous gastrointestinal epithelium in SLCT.  相似文献   
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Surface-based morphometry (SBM) is extremely useful for estimating the indices of cortical morphology, such as volume, thickness, area, and gyrification, whereas voxel-based morphometry (VBM) is a typical method of gray matter (GM) volumetry that includes cortex measurement. In cases where SBM is used to estimate cortical morphology, it remains controversial as to whether VBM should be used in addition to estimate GM volume. Therefore, this review has two main goals. First, we summarize the differences between the two methods regarding preprocessing, statistical analysis, and reliability. Second, we review studies that estimate cortical morphological changes using VBM and/or SBM and discuss whether using VBM in conjunction with SBM produces additional values. We found cases in which detection of morphological change in either VBM or SBM was superior, and others that showed equivalent performance between the two methods. Therefore, we concluded that using VBM and SBM together can help researchers and clinicians obtain a better understanding of normal neurobiological processes of the brain. Moreover, the use of both methods may improve the accuracy of the detection of morphological changes when comparing the data of patients and controls.In addition, we introduce two other recent methods as future directions for estimating cortical morphological changes: a multi-modal parcellation method using structural and functional images, and a synthetic segmentation method using multi-contrast images (such as T1- and proton density-weighted images).  相似文献   
87.
We collected information by postal survey from 622 medical institutions reported to be using telemedicine in Japan. The questionnaire asked about willingness to pay (WTP) for telemedicine and willingness to undertake (WTU) it. The Kernel Estimation Method was used to obtain WTP for teleradiology (4379 yen), telepathology (9526 yen), teleconferencing (2084 yen) and teleconsultation (633 yen). The estimated WTU were teleradiology (3875 yen), telepathology (17,918 yen), teleconferencing (3230 yen) and teleconsultation (3643 yen). These values are larger than the current charges that customers actually pay or providers receive. Multiplying these values by the number of medical institutions that had implemented telemedicine allows the total annual benefits of telemedicine to be estimated, e.g. for teleradiology, the annual benefit in terms of WTP and WTU (millions of yen per year) were 140.20 and 1101.75, respectively. Based on the results of the survey, specific policy measures to promote telemedicine further include improvement of quality and reimbursement.  相似文献   
88.
Abstract: Ultrasonography (US) is one tool for preoperative diagnosis of lymph node metastases in breast cancer. However, US cannot detect true sentinel lymph nodes (SLNs). We identified SLNs in 60 clinically node‐negative breast cancer patients using a real‐time virtual sonography (RVS) system to display in real time a virtual multi‐planar reconstruction obtained from computed tomography (CT) volume data corresponding to the same cross‐sectional image from US. CT volume data were obtained from our original three‐dimensional CT lymphography (3DCT‐LG), which accurately detects SLNs in breast cancer. SLN metastases were assessed by shape and visibility of the hilum. All patients underwent SLN biopsy and SLN metastases were examined pathologically. In all 60 patients, we were able to detect the same SLNs visualized by 3DCT‐LG. Suspicious SLN metastases were identified in seven of the 60 patients, and four of seven patients were pathologically positive. Positive predictive value was 57%. The remaining 53 patients displayed non‐suspect SLNs in which absence of metastasis from the SLN was confirmed histologically. Overall accuracy was 95%. This is a first attempt at preoperatively identifying SLNs using US guided by the RVS system in breast cancer patients. Although evaluation of SLN metastases was unsatisfactory, this method may be useful for preoperative fine‐needle aspiration cytology for diagnosis of SLN metastases.  相似文献   
89.
Surgery Today - Postoperative pneumonia affects the length of stay and mortality after surgery in elderly patients with colorectal cancer (CRC). We aimed to determine the risk factors of...  相似文献   
90.

Background

To investigate the expression of parathyroid hormone (PTH)/PTH-related peptide (PTHrP) receptor 1 (PTH1R) in clinical specimens of normal and diseased bladders. PTHrP is a unique stretch-induced endogenous detrusor relaxant that functions via PTH1R. We hypothesized that suppression of this axis could be involved in the pathogenesis of bladder disease.

Methods

PTH1R expression in clinical samples was examined by immunohistochemistry. Normal kidney tissue from a patient with renal cancer and bladder specimens from patients undergoing ureteral reimplantation for vesicoureteral reflux or partial cystectomy for urachal cyst were examined as normal control organs. These were compared with 13 diseased bladder specimens from patients undergoing bladder augmentation. The augmentation patients ranged from 8 to 31 years old (median 15 years), including 9 males and 4 females. Seven patients had spinal disorders, 3 had posterior urethral valves and 3 non-neurogenic neurogenic bladders (Hinman syndrome).

Results

Renal tubules, detrusor muscle and blood vessels in normal control bladders stained positive for PTH1R. According to preoperative urodynamic studies of augmentation patients, the median percent bladder capacity compared with the age-standard was 43.6% (range 1.5–86.6%), median intravesical pressure at maximal capacity was 30 cmH2O (range 10–107 cmH2O), and median compliance was 3.93 ml/cmH2O (range 0.05–30.3 ml/cmH2O). Detrusor overactivity was observed in five cases (38.5%). All augmented bladders showed negative stainings in PTH1R expression in the detrusor tissue, but positive staining of blood vessels in majority of the cases.

Conclusions

Downregulation of PTH1R may be involved in the pathogenesis of human end-stage bladder disease requiring augmentation.  相似文献   
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