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81.
Yoshio Gunji Kaoru Sakamoto Kouichi Kamura Kenichi Yamada Hidehiko Kashiwabara Hideaki Shimada Seiji Hori Takao Suzuki Takenori Ochiai 《Surgery today》2001,31(6):492-496
This study analyzes ten cases of malignancy in a cohort of 183 renal transplant recipients, examining surgical management,
postoperative immunosuppressive therapy, and long-term outcome. One of these ten patients, who had malignant lymphoma of the
jejunum, died of the neoplasm, but the other nine patients did not show any signs of tumor recurrence after removal. All of
these nine patients, except for one who had transplant renal cell carcinoma (RCC), received the same dose of immunosuppressive
agents after surgery for the malignant disease. Seven patients were still alive at the time of this report, six of whom had
good transplant renal function. The findings of this study indicate that even if immunosuppressive agents predispose to the
development of cancer, it is not necessary to reduce their dose after removal of the tumor.
Received: April 17, 2000 / Accepted: November 20, 2000 相似文献
82.
Gunji Y Sakamoto K Yamada K Hamaguchi K Kashiwabara H Hori S Shimada H Suzuki T Ochiai T 《Surgery today》2001,31(4):374-377
Posttransplant renal cell carcinoma (RCC) usually arises in the native kidneys of renal transplant recipients rather than
in the transplanted kidney. This report describes a case of RCC that developed in the transplanted cadaveric kidney in a 37-year-old
male recipient 9 months after transplantation. An en bloc radical transplant nephrectomy was performed, and he has subsequently
remained stable on hemodialysis for 3 years without any sign of recurrence.
Received: March 27, 2000 / Accepted: September 26, 2000 相似文献
83.
Hayashida M Nishimoto Y Matsuura T Takahashi Y Kohashi K Souzaki R Taguchi T 《Journal of pediatric surgery》2007,42(12):2097-2101
Background
Biliary atresia (BA) is a cholestatic disease of unknown etiology. It has recently been suggested that graft-vs-host disease caused by microchimerism is an etiology in the development of autoimmune disease. Moreover, the liver is a frequent target organ of graft-vs-host disease. The aim of this study is to identify the presence and extent of maternal microchimerism and to determine whether it plays a role in the etiology of BA.Methods
The liver biopsy specimens of 6 male patients with BA (BA group) and 6 males with other liver diseases (non-BA group) were assayed for X- and Y-chromosome using fluorescent in situ hybridization. The cells with 2 sex chromosomes in the nuclei were counted. Cells with 1 X- and 1 Y-chromosomes were considered to be host cells, and those with 2 X-chromosome were considered to be of maternal origin.Results
The frequency of cells with XX chromosomes per 1000 host cells in the BA group and the non-BA group were 3.00 ± 0.75 and 0.99 ± 0.50, respectively (P = .005). Moreover, the age at the time of biopsy did not affect the number of chimeric cells.Conclusion
The presence of female cells in the liver of male patients with BA was significantly higher than in males with other liver disease. Maternal microchimerism is therefore suggested to contribute to the pathogenesis of BA. 相似文献84.
Yuichi Inoue Eisei Sohara Katsuki Kobayashi Motoko Chiga Tatemitsu Rai Kenichi Ishibashi Shigeo Horie Xuefeng Su Jing Zhou Sei Sasaki Shinichi Uchida 《Journal of the American Society of Nephrology : JASN》2014,25(12):2789-2799
We previously reported that disruption of the aquaporin-11 (AQP11) gene in mice resulted in cystogenesis in the kidney. In this study, we aimed to clarify the mechanism of cystogenesis in AQP11(−/−) mice. To enable the analyses of AQP11 at the protein level in vivo, AQP11 BAC transgenic mice (TgAQP11) that express 3×HA-tagged AQP11 protein were generated. This AQP11 localized to the endoplasmic reticulum (ER) of proximal tubule cells in TgAQP11 mice and rescued renal cystogenesis in AQP11(−/−) mice. Therefore, we hypothesized that the absence of AQP11 in the ER could result in impaired quality control and aberrant trafficking of polycystin-1 (PC-1) and polycystin-2 (PC-2). Compared with kidneys of wild-type mice, AQP11(−/−) kidneys exhibited increased protein expression levels of PC-1 and decreased protein expression levels of PC-2. Moreover, PC-1 isolated from AQP11(−/−) mice displayed an altered electrophoretic mobility caused by impaired N-glycosylation processing, and density gradient centrifugation of kidney homogenate and in vivo protein biotinylation revealed impaired membrane trafficking of PC-1 in these mice. Finally, we showed that the Pkd1(+/−) background increased the severity of cystogenesis in AQP11(−/−) mouse kidneys, indicating that PC-1 is involved in the mechanism of cystogenesis in AQP11(−/−) mice. Additionally, the primary cilia of proximal tubules were elongated in AQP11(−/−) mice. Taken together, these data show that impaired glycosylation processing and aberrant membrane trafficking of PC-1 in AQP11(−/−) mice could be a key mechanism of cystogenesis in AQP11(−/−) mice.Aquaporin-11 (AQP11) is a membrane-channel protein. Although AQP11 is reported to be permeable to the water molecule,1–3 the permeability of AQP11 to other solutes remains unclear. AQP11(−/−) mice die in the neonatal period because of renal failure and retarded growth.4,5 Moreover, AQP11(−/−) mice develop renal cysts, suggesting that AQP11 can play a role in cystogenesis.4,5 However, the mechanisms of cystogenesis in AQP11(−/−) mice have yet to be clarified. One of the reasons for the difficulties in investigating AQP11 has been the lack of a good antibody for detecting endogenous AQP11 in mouse tissues.Autosomal dominant polycystic kidney disease (PKD) is the most common inherited renal disorder, occurring in 1:400 to 1:1000 live births. It is characterized by gradual renal cyst development and expansion, ultimately resulting in massive kidney enlargement and ESRD. Among autosomal dominant PKD patients, 85%–90% of cases result from mutations in the PKD1 gene, whereas another 10%–15% of cases are accounted for by mutations in the PKD2 gene. PKD1 encodes polycystin-1 (PC-1), a 462-kD, 4303–amino acid integral membrane protein with 11 transmembrane domains, a long extracellular N terminus with multiple binding domains, and a short cytoplasmic C terminus that interacts with multiple proteins, including the protein product of PKD2, polycystin-2 (PC-2).6 PC-2 is a significantly smaller 110-kD protein with six transmembrane domains. PC-1 and PC-2 are located in the plasma membrane and cilia of renal epithelia.6–8To enable the analyses of AQP11 in mice at the protein level in vivo, we generated AQP11 BAC transgenic mice (TgAQP11) that express AQP11 tagged with 3×hemagglutinin (HA) sequence at its N terminus and showed that AQP11 localizes to the endoplasmic reticulum (ER) of proximal tubule cells in vivo. Moreover, to investigate the mechanisms of cystogenesis in AQP11(−/−) mouse kidneys, we focused on PC-1 and PC-2. Impaired glycosylation processing and membrane trafficking of PC-1 in AQP11(−/−) mouse kidneys were found, which could represent a key mechanism of cyst formation in AQP11(−/−) mice. 相似文献
85.
Kurabayashi T Matsushita H Tomita M Kato N Kikuchi M Nagata H Honda A Yahata T Tanaka K 《Journal of bone and mineral metabolism》2004,22(3):241-247
We longitudinally studied whether vitamin D receptor (VDR) and estrogen receptor (ER) gene polymorphisms in Japanese women influenced the effect of longterm hormone replacement therapy (HRT) on bone mineral density (BMD) in the lumbar spine. The 81 subjects were aged 40 to 64 years (mean ± SEM, 49.5 ± 0.6 years), and had received sequential or continuous HRT regimens, including 0.625mg of conjugated equine estrogen and 2.5 to 5mg of medroxy-progesterone acetate, for at least 3 years. Genomic DNA was extracted from blood cells, and analyzed for restriction fragment length polymorphism, using the restriction endonucleases Taq I, Apa I, and Fok I for VDR, and Pvu II and Xba I for ER. At 1 year, subjects with a Taq I genotype of TT (i.e., site absent) showed a significantly greater increase in BMD with treatment (BMD) than subjects with the Tt genotype (2.6 ± 0.5% vs –0.8 ± 1.4%; P = 0.016). A small difference between genotypes remained at 2 years (3.8 ± 0.6% vs 0.8 ± 1.6%; P = 0.069), but no significant difference between genotypes was seen at 3 years. In multiple regression analyses, BMD at 1 year was significantly affected by VDR-Taq I, Apa I, and ER-Pvu II genotypes and by age at treatment initiation, although at 3 years or more, BMD was significantly affected only by age. These results indicate that Taq I VDR gene polymorphism predicted the effect on lumbar BMD for the first year of HRT in Japanese women, and that the differences in BMD versus the polymorphism disappeared if the treatment was continued for over 2 years. 相似文献
86.
Magnetic resonance imaging for preoperative evaluation of breast cancer: a comparative study with mammography and ultrasonography 总被引:11,自引:0,他引:11
Hata T Takahashi H Watanabe K Takahashi M Taguchi K Itoh T Todo S 《Journal of the American College of Surgeons》2004,198(2):190-197
BACKGROUND: The widespread use of mammographic screening has led to increased detection of small tumors that are often difficult to diagnose with conventional imaging modalities such as mammography and ultrasonography. Intraductal spread of breast cancer, a principle risk factor for local recurrence, is also difficult to diagnose with mammography and ultrasonography. We investigated the clinical usefulness of magnetic resonance imaging of the breast in the therapy of breast cancer and we compared it with mammography and ultrasonography. STUDY DESIGN: A total of 183 patients with primary breast cancer underwent surgery at our institute between September 1, 1999, and November 30, 2002. They were examined preoperatively with magnetic resonance imaging, mammography, and ultrasonography. Magnetic resonance imaging evaluation included contrast-enhanced dynamic studies using IV injection of gadolinium-diethylenetriamine pentaacetic acid. RESULTS: Detection rates of breast cancers by magnetic resonance imaging, mammography, and ultrasonography were 93.7%, 84.6%, and 97.3%, respectively (magnetic resonance imaging versus mammography, p < 0.05). Patterns of time-intensity curves in dynamic magnetic resonance imaging differed with histologic types. Sensitivity, specificity, and accuracy of detection of intraductal spread were 66.7%, 64.2%, and 65.6% with MRI; 22.2%, 85.7%, and 50% with mammography; and 20.6%, 85.2%, and 50% with ultrasonography, respectively (sensitivity, specificity, and accuracy; p < 0.05, respectively). CONCLUSIONS: Magnetic resonance imaging can diagnose breast cancer as accurately as ultrasonography and more accurately than mammography. Patterns of time-intensity curves correlated with tumor histology. In addition, magnetic resonance imaging can detect intraductal spread more accurately than the other two methods. Magnetic resonance imaging appears to be indispensable in breast-conserving surgery to minimize local recurrence. 相似文献
87.
Lymph node metastasis in T1 adenocarcinoma of the colon and rectum 总被引:11,自引:0,他引:11
Satoshi?Okabe Jinru?Shia Garrett?Nash W.?Douglas?Wong José?G.?Guillem Martin?R.?Weiser Larissa?Temple Kenichi?Sugihara Philip?B.?PatyEmail author 《Journal of gastrointestinal surgery》2004,8(8):1032-1040
The biology of colorectal cancer differs according to location within the large intestine. To evaluate the clinical significance
of tumor location as a risk factor for lymph node metastasis (LNM), we performed a detailed pathological review of T1 adenocarcinomas
of the colon and rectum. T1 adenocarcinomas of the colon and rectum treated by radical resection (n = 428) were identified
from prospective clinical databases at two institutions. Tumor location was assigned as right colon (cecum to transverse),
left colon (splenic flexure to sigmoid), or rectum (0–18 cm from AV). Pathology slides were reviewed, extent of submucosal
invasion (sm width, sm depth) was quantified using an optical micrometer, and morphologic features of the cancer and its infiltrating
margin were recorded. The overall rate of LNM was 10%. On univariate analysis, LNM was significantly more common in the rectum
(27/176, 15%) compared to the left colon (13/160, 8%, p = .04) or right colon (3/92, 3%, p = .003). However, on multivariate
analysis, deep submucosal invasion and lymphovascular invasion were independent and significant risk factors, whereas tumor
location was not. T1 colorectal cancers have a progressively higher risk of LNM as their location becomes more distal. However,
the increasing rate of LNM observed in cancers of the left colon and rectum is explained by a higher prevalence of high-risk
pathologic features. In early colorectal cancers, tumor morphology is the strongest clinical predictor of metastatic behavior.
Presented at the Forty-Fifth Annual Meeting of The Society for Surgery of the Alimentary Tract, New Orleans, Louisiana, May
15–19, 2004
Presented at the Forty-Fifth Annual Meeting of The Society for Surgery of the Alimentary Tract, New Orleans, Louisiana, May
15–19, 2004 相似文献
88.
To determine the availability and limitations of the detection of ischemic lesions by stress thallium-201 myocardial SPECT as the daily routine procedure, we compared and evaluated the detectability of the quantitative analysis (%uptake and washout rate (WR)) and visual evaluation in 104 patients with effort angina and 17 normal subjects. Visual evaluation combined with WR analysis resulted in significantly higher sensitivity (88.0%) but lower specificity (60.2%) than the other methods. The sensitivity by visual evaluation was quite low in multivessel disease (MVD), and in the regions supplied by mild coronary stenosis or by the left circumflex artery. These were markedly improved by combining visual evaluation and WR analysis, but sensitivity in the MVD group was unsatisfactory even with this analytic method in comparison with the single vessel disease group. One of the causes of low sensitivity in the MVD group might be the "true negative": No induction of the ischemia in the regions of milder stenosis, or the regions supplied by the collateral coronary flow. We therefore conclude that the combination of visual evaluation as a qualitative analysis and WR analysis as a quantitative analysis, is the most useful daily routine procedure as a screening test for detecting ischemia. 相似文献
89.
Tomiguchi S Kumita S Hashimoto J Inoue T Nomura Y Emoto J Nakajima K Nishimura T 《Kaku igaku. The Japanese journal of nuclear medicine》2002,39(1):37-46
The aim of this study was to evaluate the clinical usefulness of attenuation and scatter correction (AC, SC) on a 201Tl myocardial single-photon emission computed tomography (201Tl SPECT) as a multi-center trial. With a dual-detecter and a triple-detector SPECT systems with a 99mTc transmission source, simultaneous transmission/emission tomography (TCT/ECT) was performed on 38 patients with angiographically coronary heart disease (CHD) and 26 patients without evidence of CHD. Stress and delayed attenuation and scatter corrected images (SAC) and uncorrected images (NC) were reconstructed. On NC images of normal cases, influence of attenuation was greater in male than female. In comparison of 201Tl distribution between male and female, significant decrease in 201Tl activity was observed in the inferoposterior wall in male and that was observed in the anterobasal wall of the left myocardium in female. Such a difference in 201Tl distribution between male and female disappeared on SAC images. On the diagnostic performance for the identification of CHD, SAC images demonstrated improved specificity and accuracy values in the right coronary arterial territory (RCA) with visual analysis statistically. Sensitivity value in the RCA was also improved, but it was not statistically significant. Sensitivity value in the left circumflex arterial territory (LCX) increased without decrease in specificity value on SAC images. In the left anterior descending arterial territory (LAD), sensitivity value increased on SAC images. Although specificity value decreased on SAC images in LAD territory, it was not statistically significant. The difference in 201Tl distribution between male and female is improved in normal cases by attenuation and scatter correction on 201Tl myocardial SPECT. Diagnostic performance of CHD is also improved by attenuation and scatter correction, especially in territories of which specificity in assessing the absence of disease have been suboptimal. In conclusion, attenuation and scatter correction on 201Tl myocardial SPECT is considered to be clinically useful. 相似文献
90.
The retention indices of 201Tl-SPECT in brain tumors 总被引:1,自引:0,他引:1
Otsuka H Shinbata H Hieda M Yamashita K Kitamura H Senba T Kashihara K Tagashira H 《Annals of nuclear medicine》2002,16(7):455-459
OBJECTIVE: The aim of this study was to assess the utility of 201Tl SPECT in the differential diagnosis of intracranial tumors and to determine the relationship between 201Tl uptake and histological types. METHODS: Thirty-eight patients (19 males and 19 females) with thirty-eight brain tumors were evaluated with 201Tl-SPECT. The early and delayed 201Tl uptake ratio was calculated, and the retention index (RI) was applied as follows; RI = delayed uptake ratio/early uptake ratio. RESULTS: The RI of malignant tumors was higher (0.72 +/- 0.18) than that of benign tumors (0.50 +/- 0.16) and the difference was statistically significant (p = 0.00045). The difference between high-grade glioma (0.80 +/- 0.15) and metastatic tumors (0.64 +/- 0.19) was statistically significant (p = 0.039). CONCLUSION: 201Tl-SPECT may add useful biochemical information and could differentiate malignant brain tumors from benign lesions, but the RI of metastatic tumors varied depending on the organs with the primary lesion and histological types. 相似文献