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61.
Takayama Y Kishimoto R Hanaoka S Nonaka H Kandatsu S Tsuji H Tsujii H Ikehira H Obata T 《Journal of magnetic resonance imaging : JMRI》2008,27(6):1331-1335
PURPOSE: To assess the apparent diffusion coefficient (ADC) value and diffusion tensor image (DTI) including fractional anisotropy (FA) of the noncancerous prostate and prostate cancer before and after carbon-ion radiotherapy (CIRT). MATERIALS AND METHODS: Nine patients with biopsy-proven prostate cancer underwent 1.5T magnetic resonance (MR) examinations. One patient with benign prostatic hypertrophy and one healthy volunteer were also examined as references. The changes in ADC values and DTI of the entire prostate calculated from b-values of 0 and 700 (s/mm(2)) were estimated between before and after CIRT. RESULTS: ADC values of prostate cancer significantly increased after CIRT by paired t-test (P < 0.01) but those of noncancerous inner gland (IG) and peripheral zone (PZ) showed no significant change. By analysis of variance, significant differences in ADC values were observed among prostate cancer and noncancerous IG and PZ before CIRT (P < 0.05). After CIRT, those significant differences had disappeared. FAs showed no significant differences in any comparisons. DTI showed changes in the direction of the main axis of the tensor in prostate cancer after CIRT. CONCLUSION: There were changes in ADC and DTI in prostate cancer after CIRT. They may be useful for monitoring prostatic structural changes under radiotherapy. 相似文献
62.
Development of a therapeutic adenoviral vector for cholangiocarcinoma combining tumor-restricted gene expression and infectivity enhancement 总被引:2,自引:0,他引:2
Peter Nagi M.D. Selwyn M. Vickers M.D. Julia Davydova M.D. Ph.D. Yasuo Adachi M.D. Ph.D. Koichi Takayama M.D. Ph.D. Shannon Barker Victor Krasnykh Ph.D. David T. Curiel M.D. Masato Yamamoto M.D. Ph.D. 《Journal of gastrointestinal surgery》2003,7(3):364-371
Cholangiocarcinoma is an invasive malignancy that is most often unresectable upon diagnosis and unresponsive to chemotherapy
and radiation. While adenoviral gene therapy has shown promise in treating many tumors, systemic toxicity and low tumor transduction
efficiency have hampered its application in many gastrointestinal cancers. To overcome these difficulties, we have constructed
an adenoviral vector utilizing a tumor-specific promoter (TSP) for selective transgene expression and a vector with an RGD-motif
in the fiber-knob region for infectivity enhancement. In seeking a TSP for cholangiocarcinoma, Secretory Leukoprotease Inhibitor,
Midkine, Gastrin Releasing Peptide, VEGF, Cox-2M, and Cox-2L promoters were configures in adenoviral vectors, and evaluated
in cholangiocarcinoma cells lines (Oz and SkChA-1). Luciferase assays demonstrated that Cox-2 promoters (M and L) showed the
highest promoter activity, with Cox-2M appearing slightly stronger than Cox-2L. Infectivity enhanced vectors with RGD-motif
in the fiber-knob region were also constructed with the luciferase transgene driven by a CMV control and the Cox-2M and Cox-2L
promoters. Subsequent luciferase assays comparing the unmodified vectors to the RGD-modified versions demonstrated higher
levels of luciferase activity than the RGD-infected cells. This paradigm was then applied to a therapeutic HSV-TK/GCV model
by constructing RGD-enhanced HSV-TK vectors driven by Cox-2M and Cox-2L promoters. In vitro cytocidal effect analysis confirmed
that the RGD-modified, cox-2 (M and L) driven vectors showed a stronger cytocidal effect upon gancyclovir administration than
the vectors with wild-type fiber. The Cox-2 promoter demonstrates a favorable selectivity profile for cholangiocarcinoma,
and RGD-modification further enhances transduction efficiency. This combination has potential to overcome the obstacles to
clinical application of adenoviral gene therapy in cholangiocarcinoma.
Presented at the Forty-Third Annual Meeting of The Society for Surgery of The Alimentary Tract, San Francisco, California,
May 19–22, 2002 (oral presentation). 相似文献
63.
Branch patch reconstruction in living donor liver transplantation: arterialization of grafts with replaced type arteries 总被引:5,自引:0,他引:5
We developed a hepatic arterialization technique in living donor liver transplantation. The technique was indicated in patients with a left graft from donors with a right hepatic artery originated from superior mesenteric artery or a right graft from donors with a left hepatic artery from left gastric artery. The donor common hepatic and gastroduodenal arteries were split. On the recipient side, left and right hepatic arteries or branches of the right hepatic artery were split, received patch plasty, and anastomosed with the graft arteries under loupe observation. Livers from 25 donors were procured (16 right livers and 9 left livers) using this technique. There were no vascular complications in the donors. Three recipients died due to infectious disease with arterial patency. The remaining 22 recipients survived without hepatic arterial thrombosis. In limited situations, this technique can be adapted for living donor liver transplantation without increasing donor complications. 相似文献
64.
Daisuke Yoshioka Hiroo Takayama Arthur R. Garan Veli K. Topkara Jiho Han Boyganzi Li Paul Kurlansky Melana Yuzefpolskaya Paolo C. Colombo Yoshifumi Naka Koji Takeda 《The Journal of thoracic and cardiovascular surgery》2017,153(4):752-762.e5
Objective
The role of short-term mechanical circulatory support has increased in patients with refractory cardiogenic shock. However, limited data exist on the outcomes of a bridge to a durable left ventricular assist device strategy using short-term mechanical circulatory support.Methods
We retrospectively reviewed 382 patients who underwent continuous-flow left ventricular assist device insertion between 2004 and 2014. Of these, 45 (12%) were bridged with short-term mechanical circulatory support devices for refractory cardiogenic shock. We analyzed early and midterm outcomes in this bridged cohort. Multivariate Cox proportional hazards modeling was performed to evaluate the predictor of overall death in the entire cohort.Results
The mean age of the bridged cohort was 53 ± 10 years, and 87% were male. The types of initial support included percutaneous devices in 24 patients (53%) and external continuous-flow ventricular assist device in 21 patients (47%). The median duration of short-term mechanical circulatory support was 14.0 (interquartile range, 7.5-29.5) days. The short-term mechanical circulatory support significantly improved end-organ function and hemodynamics. After conversion to durable left ventricular assist device insertion, in-hospital mortality was 18%. The incidence of right ventricular assist device use was high at 27%. The overall survival was 70% and 62% at 1 and 2 years, respectively. Cox multivariate hazard analysis in the entire cohort demonstrated that the use of a postoperative right ventricular assist device was a significant predictor of overall death (hazard ratio, 4.04; P < .001; 95% confidence interval, 1.97-7.94), but the use of a short-term mechanical circulatory support was not (P = .937).Conclusions
Short-term mechanical circulatory support can optimize patients in refractory cardiogenic shock and serve as a bridge to implantation of a durable left ventricular assist device. However, the early mortality rate after durable left ventricular assist device implantation is high because of unrecognized right ventricular failure. 相似文献65.
Cyclin‐Dependent Kinase Inhibitor‐1‐Deficient Mice are Susceptible to Osteoarthritis Associated with Enhanced Inflammation 下载免费PDF全文
Shinsuke Kihara Shinya Hayashi Shingo Hashimoto Noriyuki Kanzaki Koji Takayama Tomoyuki Matsumoto Nobuaki Chinzei Kenjiro Iwasa Masahiko Haneda Kazuhiro Takeuchi Kotaro Nishida Ryosuke Kuroda 《Journal of bone and mineral research》2017,32(5):991-1001
Osteoarthritis (OA) is a multifactorial disease, and recent data suggested that cell cycle–related proteins play a role in OA pathology. Cyclin‐dependent kinase (CDK) inhibitor 1 (p21) regulates activation of other CDKs, and recently, we reported that p21 deficiency induced susceptibility to OA induced by destabilization of the medial meniscus (DMM) surgery through STAT3‐signaling activation. However, the mechanisms associated with why p21 deficiency led to susceptibility to OA by the STAT3 pathway remain unknown. Therefore, we focused on joint inflammation to determine the mechanisms associated with p21 function during in vitro and in vivo OA progression. p21‐knockout (p21?/?) mice were used to develop an in vivo OA model, and C57BL/6 (p21+/+) mice with the same background as the p21?/? mice were used as controls. Morphogenic changes were measured using micro‐CT, IL‐1β serum levels were detected by ELISA, and histological or immunohistological analyses were performed. Our results indicated that p21‐deficient DMM‐model mice exhibited significant subchondral bone destruction and cartilage degradation compared with wild‐type mice. Immunohistochemistry results revealed p21?/? mice susceptibility to OA changes accompanied by macrophage infiltration and enhanced MMP‐3 and MMP‐13 expression through IL‐1β‐induced NF‐κB signaling. p21?/? mice also showed subchondral bone destruction according to micro‐CT analysis, and cathepsin K staining revealed increased numbers of osteoclasts. Furthermore, p21?/? mice displayed increased serum IL‐1β levels, and isolated chondrocytes from p21?/? mice indicated elevated MMP‐3 and MMP‐13 expression with phosphorylation of IκB kinase complex in response to IL‐1β stimulation, whereas treatment with a specific p‐IκB kinase inhibitor attenuated MMP‐3 and MMP‐13 expression. Our results indicated that p21‐deficient DMM mice were susceptible to alterations in OA phenotype, including enhanced osteoclast expression, macrophage infiltration, and MMP expression through IL‐1β‐induced NF‐κB signaling, suggesting that p21 regulation may constitute a possible therapeutic strategy for OA treatment. © 2017 American Society for Bone and Mineral Research. 相似文献
66.
L. G. Machado D. S. Domiciano C. P. Figueiredo V. F. Caparbo L. Takayama R. M. Oliveira J. B. Lopes P. R. Menezes R. M. R. Pereira 《Osteoporosis international》2016,27(12):3525-3533
Summary
The present study investigates the relationship between visceral fat measured by dual-energy X-ray absorptiometry (DXA) and the incidence of non-spine fractures in community-dwelling elderly women. We demonstrated a potential negative effect of visceral fat on bone health in nonobese women.Introduction
The protective effect of obesity on bone health has been questioned because visceral fat has been demonstrated to have a deleterious effect on bone. The aim of this study was to investigate the association of visceral fat measured by DXA with the incidence of non-spine fractures in community-dwelling elderly women.Methods
This longitudinal prospective population-based cohort study evaluated 433 community-dwelling women aged 65 years or older. A specific clinical questionnaire, including personal history of a fragility fracture in non-spine osteoporotic sites, was administered at baseline and after an average of 4.3 years. All incidences of fragility fractures during the study period were confirmed by affected-site radiography. Visceral adipose tissue (VAT) was measured in the android region of a whole-body DXA scan.Results
The mean age was 72.8?±?4.7 years, and 28 incident non-spine osteoporotic fractures were identified after a mean follow-up time of 4.3?±?0.8 years. According to the Lipschitz classification for nutritional status in the elderly, 38.6 % of women were nonobese (BMI?≤?27 kg/m2) and 61.4 % were obese/overweight. Logistic regression models were used to estimate the relationship between VAT and non-spine fractures in elderly women. After adjusting for age, race, previous fractures, and BMD, VAT (mass, area, volume) had a significant association with the incidence of non-spine fractures only in nonobese elderly women (VAT mass: OR, 1.42 [95 % CI, 1.09–1.85; p?=?0.010]; VAT area: OR, 1.19 [95 % CI, 1.05–1.36; p?=?0.008]; VAT volume: OR, 1.40 [95 % CI, 1.09–1.80; p?=?0.009]).Conclusion
This study suggests a potential negative effect of visceral adiposity on bone health in nonobese women.67.
Masutani K Fujisaki K Maeda H Toyonaga J Inoshima I Takayama K Katafuchi R Hirakata H Tsuruya K Iida M 《Clinical and experimental nephrology》2008,12(5):398-402
A 52-year-old Japanese female was admitted to our hospital for microhematuria, proteinuria and progressive renal dysfunction.
Two years prior to admission, she was diagnosed with lung adenocarcinoma and multiple bone and brain metastases, and was treated
with gefitinib (250 mg/day). Treatment for 6 months induced partial response with 30% regression of the primary lung tumor,
and resolution of metastatic tumors. After confirmation of the partial remission state, we performed percutaneous renal biopsy.
Glomeruli showed mild to moderate mesangial proliferation, segmental endocapillary proliferation and occasional fibrocellular
crescent formation. In addition, severe interstitial fibrosis and tubular atrophy relative to the degree of glomerular sclerosis
were noted. Immunofluorescence microscopy showed predominant IgA deposition in the mesangial area. Electron microscopy revealed
subepithelial and paramesangial electron-dense deposits. In consideration of the prognosis of lung cancer and complication
of immunosuppressive treatment, we continued gefitinib only and closely followed-up the clinical course in the outpatient
clinic. Sixteen months later, she continued to have proteinuria and microhematuria, and the severity of renal dysfunction
was still the same. However, the lung cancer started to increase in size. This is quite an unusual case presenting histologically
with tubulointerstitial nephritis and IgA nephropathy in a patient on long-term treatment with gefitinib. 相似文献
68.
Kazushi Takayama Akinobu Suzuki Tomoya Manaka Susumu Taguchi Yusuke Hashimoto Yuuki Imai Shigeyuki Wakitani Kunio Takaoka 《Journal of bone and mineral metabolism》2009,27(4):402-411
Noggin is a major extracellular antagonist to bone morphogenetic proteins (BMPs) which binds to BMPs and blocks binding of
them to BMP-specific receptors and negatively regulates BMP-induced osteoblastic differentiation. In this study, we investigated
the effect of noggin silencing by transfection of small interfering RNA (siRNA) on BMP-induced osteoblastic differentiation
in vitro and ectopic bone formation in vivo induced by recombinant human BMP-2 (rhBMP-2). Noggin mRNA expression was up-regulated
in response to rhBMP-2 in C2C12 cells, a myoblastic cell line, in dose- and time-dependent fashion as determined by real-time
RT-PCR assay. Silencing of noggin expression by transfection of noggin siRNA suppressed BMP-stimulated noggin expression,
resulting in acceleration of BMP-induced osteoblastic differentiation. For in vivo noggin silencing, siRNA was injected locally
into back muscles and transfected into local cells by electroporation, where rhBMP-2-retaining (5 μg) collagen disks had been
surgically placed. The implants were harvested at 2 weeks after surgery from experimental and control group mice and analyzed
by radiological and histological methods. As a result, bone mineral content of ossicles ectopically induced by rhBMP-2 was
significantly increased by silencing of noggin. Our findings suggest that silencing of noggin enhances the osteoblastic differentiation
of BMP-responding cells in vitro and new bone formation induced by rhBMP-2 in vivo by eliminating negative regulation of the
effects of BMP. RNA interference might be useful for intensifying the effects of BMP in promoting new bone (callus) formation
in repair of damaged bone. 相似文献
69.
Takuichi Oikawa Tadatoshi Takayama Shunji Okada Tomohisa Kamo Masahiko Sugitani Michiie Sakamoto 《Journal of Hepato-Biliary-Pancreatic Surgery》2009,16(1):90-93
We present a case of multiple colorectal liver metastases with macroscopic portal vein thrombi. A 55-year-old woman presented
to us with rectosigmoid cancer and presented with two liver metastases. The tumor in the posterior sector was associated with
invasion of first order branches of the portal vein. We performed low anterior resection, hepatic posterior sectorectomy and
partial left anterior sectorectomy. Both the colorectal cancer and liver tumors exhibited histological characteristics of
moderately differentiated adenocarcinoma with a substantial amount of mucin production. The liver metastases were associated
with prominent tumor thrombi in many branches of the portal vein. Stronger staining for endoglin (CD 105) than for Fas ligand
(Fas L) and matrix metalloproteinase (MMP-2) was observed in both the colorectal cancer and metastatic liver tumor cells.
Expression of the vascular endothelial growth factor within the tumor cells was seen in both the colorectal cancer as well
as the metastatic liver tumor cells. Six months after the operation, she was diagnosed to have multiple, more than about 20
liver metastases, and in 9 months after the operation, the patient died. The colorectal cancer with liver metastases associated
with portal vein tumor thrombosis was poor prognosis, found neoplastic microvessel formation. 相似文献
70.
Yasuyuki?Fukami Yuji?KaneokaEmail author Atsuyuki?Maeda Yuichi?Takayama Shunsuke?Onoe Masatoshi?Isogai 《Surgery today》2016,46(2):176-182