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991.
Tamura T Usui S Murakami S Arihiro K Fujimoto T Yamada T Naito K Akiyama M 《Magnetic resonance in medicine》2012,68(3):890-897
Previous studies have reported that the signal attenuation of diffusion weighted magnetic resonance imaging for tumor tissues displays a non-monoexponential biexponential decay, and the apparent diffusion coefficients (ADCs) can be divided into a fast and slow diffusion component by using a simple biexponential decay model. The purpose of this study is to examine the non-monoexponential character of the diffusion weighted magnetic resonance imaging signal attenuations of breast cancers, estimate the fast and slow diffusion components, and compare them with the extra- and intracellular component information obtained from the pathological specimens. Twenty-two subjects having breast cancers underwent diffusion weighted magnetic resonance imaging using six b-values up to 3500 s/mm(2) and the signal attenuations were analyzed using the biexponential function. The derived slow component fraction correlated with the cellular fraction and the ADCs converged to 0.2-0.3 × 10(-3) mm(2) /s for the higher cellular fractions. The ADCs of the fast component ranged from 1.3 to 3.9 × 10(-3) mm(2) /s and showed no correlation with the extracellular components. This result suggests that the main reason for the decreasing ADC of a breast tumor is the decreasing fraction of the fast component and the increasing fraction of the slow component having a low ADC rather than the decreasing ADC of the fast component by the restricted water diffusion in the reduced extracellular spaces. 相似文献
992.
Tsuruyama T Fujimoto Y Yonekawa Y Miyao M Onodera H Uemoto S Haga H 《Transplant international》2012,25(5):537-544
Immunological responses in human intestinal allografts are poorly understood and accurate diagnosis of acute cellular rejection remains difficult. Here, human intestinal allografts were analyzed by multi-color quantitative fluorescent immunohistochemical morphometry in order to monitor the clinical course of rejection. Morphometry gave two-dimensional plots based on size and circularity, and identified phenotypes of individual cells infiltrating the allograft by fluorescent staining. Using this method, invariant TCRVα24(+) NKT (iNKT) cells were observed in the intestinal allograft during rejection. Because these were not identified in the normal donor intestine before surgery, this finding was considered to be a signature of acute cellular rejection of the intestinal allograft. Infiltrating iNKT cells released IL-4 and IL-5, Th2-related cytokines that antagonize the Th1 responses that induce acute cellular rejection. Histological observation suggested eosinophilic enteritis in the mucosa with elevation of IL-4 and IL-5. In conclusion, iNKT cells were recruited to the intestine; however, because higher levels of IL-4 and IL-5 may contribute to eosinophilic enteritis, timely steroid administration is recommended for allograft injury due to enteritis, as well as acute cellular rejection. 相似文献
993.
Impact of FOXA1 Expression on the Prognosis of Patients with Hormone Receptor-Positive Breast Cancer
Hisamatsu Y Tokunaga E Yamashita N Akiyoshi S Okada S Nakashima Y Aishima S Morita M Kakeji Y Maehara Y 《Annals of surgical oncology》2012,19(4):1145-1152
Background
Assessing indications for adjuvant chemotherapy (CT) in patients with hormone receptor (HR)-positive/human epidermal receptor 2 (HER2)-negative breast cancer remains a challenge for oncologists. In this study, we evaluated whether forkhead-box protein A1 (FOXA1) expression was a prognostic and predictive marker for HR-positive breast cancer. 相似文献994.
Okada S Tokunaga E Kitao H Akiyoshi S Yamashita N Saeki H Oki E Morita M Kakeji Y Maehara Y 《Annals of surgical oncology》2012,19(5):1499-1507
Background
BRCA1 and BRCA2 are two major tumor suppressor genes for hereditary breast and ovarian cancer. In sporadic breast cancer, although somatic mutations of these genes are rare, loss of heterozygosity (LOH) at BRCA1 and BRCA2 loci is common. 相似文献995.
Daiki Hashimoto Mizuki Kajimoto Yuko Ueda Taiju Hyuga Kota Fujimoto Saaya Inoue Kentaro Suzuki Tomoya Kataoka Kazunori Kimura Gen Yamada 《Reproductive Medicine and Biology》2021,20(2):199-207
PurposeErectile dysfunction (ED) is one of the increasing diseases with aging society. The basis of ED derived from local penile abnormality is poorly understood because of the complex three‐dimensional (3D) distribution of sinusoids in corpus cavernosum (CC). Understanding the 3D histological structure of penis is thus necessary. Analyses on the status of regulatory signals for such abnormality are also performed.MethodsTo analyze the 3D structure of sinusoid, 3D reconstruction from serial sections of murine CC were performed. Histological analyses between young (2 months old) and aged (14 months old) CC were performed. As for chondrogenic signaling status of aged CC, SOX9 and RBPJK staining was examined.ResultsSinusoids prominently developed in the outer regions of CC adjacent to tunica albuginea. Aged CC samples contained ectopic chondrocytes in such regions. Associating with the appearance of chondrocytes, the expression of SOX9, chondrogenic regulator, was upregulated. The expression of RBPJK, one of the Notch signal regulators, was downregulated in the aged CC.ConclusionsProminent sinusoids distribute in the outer region of CC which may possess important roles for erection. A possibility of ectopic chondrogenesis induced by alteration of SOX9/Notch signaling with aging is indicated. 相似文献
996.
Eriko Sakamoto Yusuke Seino Ayako Fukami Naohiro Mizutani Shin Tsunekawa Kota Ishikawa Hidetada Ogata Eita Uenishi Hideki Kamiya Yoji Hamada Hiroyuki Sato Norio Harada Yukiyasu Toyoda Ichitomo Miwa Jiro Nakamura Nobuya Inagaki Yutaka Oiso Nobuaki Ozaki 《Journal of diabetes investigation.》2012,3(5):432-440
Aims/Introduction: Excessive intake of sucrose can cause severe health issues, such as diabetes mellitus. In animal studies, consumption of a high‐sucrose diet (SUC) has been shown to cause obesity, insulin resistance and glucose intolerance. However, several in vivo experiments have been carried out using diets with much higher sucrose contents (50–70% of the total calories) than are typically ingested by humans. In the present study, we examined the effects of a moderate SUC on glucose metabolism and the underlying mechanism. Materials and Methods: C57BL/6J mice received a SUC (38.5% sucrose), a high‐starch diet (ST) or a control diet for 5 weeks. We assessed glucose tolerance, incretin secretion and liver glucose metabolism. Results: An oral glucose tolerance test (OGTT) showed that plasma glucose levels in the early phase were significantly higher in SUC‐fed mice than in ST‐fed or control mice, with no change in plasma insulin levels at any stage. SUC‐fed mice showed a significant improvement in insulin sensitivity. Glucagon‐like peptide‐1 (GLP‐1) secretion 15 min after oral glucose administration was significantly lower in SUC‐fed mice than in ST‐fed or control mice. Hepatic glucokinase (GCK) activity was significantly reduced in SUC‐fed mice. During the OGTT, the accumulation of glycogen in the liver was suppressed in SUC‐fed mice in a time‐dependent manner. Conclusions: These results indicate that mice that consume a moderate SUC show glucose intolerance with a reduction in hepatic GCK activity and impairment in GLP‐1 secretion. (J Diabetes Invest, doi: 10.1111/j.2040‐1124.2012.00208.x , 2012) 相似文献
997.
998.
Maruyama M Murakami R Nakaguchi Y Kakei K Takenaga E Tsujita N Omura Y Kodabashi T Yokoo T Saito T Matsuyama T 《Nihon Hoshasen Gijutsu Gakkai zasshi》2012,68(2):162-168
The purpose of this study was to evaluate the reliability of cone-beam computed tomography (CBCT)-derived adaptive radiotherapy. We evaluate planning computed tomography (pCT) and CBCT in 50 patients who had undergone image guided radiotherapy (IGRT) with CBCT. Irradiated sites included head, neck, chest, abdomen, and pelvis; there were 10 patients in each group. Treatment plans including 153 beam data were recalculated based on CBCT. To compare between pCT and CBCT, we estimated CT values of normal tissues, body contour, effective depth, and monitor units (MU) calculation. The maximum difference in CT values was observed in lung estimation. The 5 mm or more differences in depth were observed in 2 beams of 2 pelvic cases, but CBCT also demonstrated a shift of abdominal wall due to intestinal motility. There were downward trends for the effective depth and MU based on CBCT, especially in lung cases. However, the differences in prescribed dose due to MU calculation were less than 5% because all patients were treated with a multifield irradiation plan. CBCT provides not only precise daily setup but also accurate anatomical information on body contour. In addition, CBCT may be considered as a useful tool for dose calculation. 相似文献
999.
T Sano H Matsutani T Kondo S Fujimoto T Sekine T Arai H Morita S Takase 《Nihon Hoshasen Gijutsu Gakkai zasshi》2012,68(8):951-960
Background: Because coronary computed tomography angiography (CCTA) by 320-area detector CT (320-ADCT) can be obtained in a short time, the probability of meeting up with premature contraction (PC) during scanning may be lower in 320-ADCT compared to 64-MDCT. The purpose is to compare the probability of meeting up with PC, scanning time, and image quality in patients with PC between the 2 groups (320-ADCT vs 64-MDCT). Methods: We have never rejected any CCTA examination due to arrhythmias. The 320-ADCT was performed in 2424 consecutive patients to include 70 atrial fibrillations (Afibs) and 64-MDCT in 1905 consecutive patients to include 51 Afibs. After exclusion of the patients with Afibs, we studied the probability of meeting up with PC during scanning and we compared the scanning time, image quality, and reconstruction phase for patients with PC between the 2 groups. Results: The probability of meeting up with PC during scanning in 320-ADCT (2.0%) is significantly lower (P<0.0001) than 64-MDCT (5.6%). For patients with PC, scanning time in 320-ADCT (2.9±0.6 s) was significantly shorter (P<0.0001) than 64-MDCT (9.5±1.9 s) and image quality in 320-ADCT (2.9±0.3 points) was significantly higher (P<0.0001) than 64-MDCT (2.2±0.8 points). CCTA was reconstructed in mid-diastolic phase in 93% of patients with PC using the 320-ADCT with arrhythmia rejection system. Conclusion: The scanning time of 320-ADCT was 1/3 in comparison with that of 64-MDCT, and the probability of meeting up with PC during scanning in 320-ADCT was 1/3 in comparison with that in 64-MDCT. 相似文献
1000.