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971.
Ricardo Celestino Eva Sigstad Marthe Løvf Gard O. S. Thomassen Krystyna K. Grøholt Lars H. Jørgensen Aasmund Berner Patrícia Castro Ragnhild A. Lothe Trine Bjøro Manuel Sobrinho‐Simões Paula Soares Rolf I. Skotheim 《Genes, chromosomes & cancer》2012,51(12):1154-1164
Neoplasms frequently present structural chromosomal aberrations that can alter the level of expression of a protein or to the expression of an aberrant chimeric protein. In the thyroid, the PAX8‐PPARG fusion is present in the neoplastic lesions that have a follicular architecture—follicular thyroid carcinoma (FTC) and follicular variant of papillary thyroid carcinoma (FVPTC), and less frequently in follicular thyroid adenoma (FTA), while the presence of RET/PTC fusions are largely restricted to papillary thyroid carcinoma (PTC). The ability to detect fusion genes is relevant for a correct diagnosis and for therapy. We have developed a new fusion gene microarray‐based approach for simultaneous analysis of all known and predicted fusion gene variants. We did a comprehensive screen for 548 known and putative fusion genes in 27 samples of thyroid tumors and three positive controls—one thyroid cancer cell line (TPC‐1) and two PTCs with known CCDC6‐RET (alias RET/PTC1) fusion gene, using this microarray. Within the thyroid tumors tested, only well known, previously reported fusion genes in thyroid oncology were identified. Our results reinforce the pathogenic role played by RET/PTC1, RET/PTC3, and PAX8‐PPARG fusion genes in thyroid tumorigenesis. © 2012 Wiley Periodicals, Inc. 相似文献
972.
BackgroundMelusin, a muscle-specific integrin-linked protein, has been reported to be a biomechanical sensor and to protect the heart from pressure overload. In the present study, we investigated the possible role that melusin plays during cardiac remodeling after myocardial infarction (MI).MethodsWe constructed a heart failure model of rats induced by left anterior descending coronary artery ligation. At different time points (1, 2, 3, 4, 6, and 8 weeks) following the operation, cardiac function was monitored by echocardiography and hemodynamic assessment; cardiac morphology was measured using hematoxylin–eosin-stained sections. Melusin expression, as well as p-Akt, Akt, and one of the Rho small GTPase family members, CDC42, was determined dynamically by Western blotting analysis during the postinfarction cardiac remodeling.ResultsProgressive increase in left ventricular (LV) end-systolic dimension and LV end-diastolic dimension and decrease in percent LV fractional shortening (%FS) and LVdp/dtmax demonstrated gradually deteriorated cardiac function in rats following MI operation. Morphological analysis revealed cardiac remodeling in MI animals, including increased LV diameter and decreased border zone thickness. We also showed a dynamic change in melusin during heart failure progression; it had an initial decline which was evident at 3 weeks and increased subsequently, reaching peak levels at 6 weeks. This dynamic change in melusin was significantly correlated with %FS and LVdp/dtmax. p-Akt/Akt and CDC42 protein expression was correlated with melusin content.ConclusionsThe altered melusin pathways and CDC42 parallel the cardiac function progression during cardiac remodeling post-MI. The dynamic change of them during this procedure may represent an important molecular mechanism underlying postinfarction cardiac remodeling and provide potential therapeutic targets. 相似文献
973.
974.
目的探讨离心泵后负荷压力对血液破坏的影响。方法采用计算流体仿真(CFD),实现Sarns2000离心血泵的数值分析。对比分析该泵有后负荷工况和空载状态时泵内液体流速、压力、剪切力的差异。结果在1 400 r/min转速下,有后负荷时流速降低,泵的流量降低。泵内压力增大,溶血破坏增加;但剪切力大于150 Pa的区域小于0.000 032%,对溶血的控制较好。结论后负荷压力会导致Sarns2000离心泵内溶血破坏的概率增加,但不会出现因剪切力导致大量溶血的问题。 相似文献
975.
Spinderjeet Gill-Samra Thomas Ng Mark Dexter Mark Wong Najmun Nahar Katherine Allsopp Rose A. Boadle Winny Varikatt 《Journal of clinical neuroscience》2012,19(10):1456-1458
Histiocytic sarcoma is a rare malignant neoplasm of the lympho-hematopoietic system that usually occurs in the skin, lymph nodes and intestinal tract. We present a 36-year-old woman with a rare histiocytic sarcoma with isolated central nervous system (CNS) involvement of multifocal circumscribed lesions. Biopsy of the brain lesions showed diffuse proliferation of pleomorphic histiocytes that were immunopositive for CD45, CD68 and CD163. Various cytokeratins and markers of lymphoma, melanoma, germ cell tumours and primary CNS tumours were negative. Examination of bone marrow trephine and a whole-body positron emission tomography scan showed no evidence of involvement of any other organ systems, thus establishing the primary nature of the lesion. The neoplastic cells uniquely showed eosinophilic globules within the cytoplasm, which were positive for CD68. These globules were shown by electron microscopy to be collections of lysosomes. A thorough discussion of the differential diagnosis and literature review is included. 相似文献
976.
Sang Woo Park Song Am Lee Jae Joon Hwang Ik Jin Yun Jun Seok Kim Seong-Hwan Chang Hyun Keun Chee Il Soo Chang 《Korean journal of radiology》2011,12(4):481-486
Objective
We wanted to evaluate the effectiveness of endovenous ablation of the incompetent vein of Giacomini using a 980-nm diode laser.Materials and Methods
A total of 18 patients (18 limbs, 4%) had the incompetent vein of Giacomini. Retrograde reflux originating from the great saphenous vein was noted in sixteen limbs and paradoxical diastolic anterograde reflux from the saphenopopliteal junction was observed in two limbs. After tumescent anesthesia, laser ablation using a 980-nm wavelength laser fiber was performed under ultrasound and/or fluoroscopic guidance. Patients were evaluated clinically and with duplex ultrasound at one week and at one, three, six and twelve months after laser ablation for the technical and clinical success.Results
In the 18 limbs, the technical success rate was 100%. Continued closure of the vein of Giacomini was seen in 18 of 18 limbs after one month, in 12 of 12 limbs after three and six months and in six of six limbs after twelve months. No recanalization of the vein and no major complications occurred.Conclusion
Endovenous laser ablation with a 980-nm wavelength is an effective and safe procedure for treating an incompetent vein of Giacomini. 相似文献977.
978.
979.
Johnny Chahine Amer N. Kadri Rama D. Gajulapalli Amar Krishnaswamy Stephanie Mick Oscar Perez Hassan Lak Raunak M. Nair Bryce Montane James Tak E. Murat Tuzcu Brian Griffin Lars G. Svensson Serge C. Harb Samir R. Kapadia 《JACC: Cardiovascular Interventions》2019,12(22):2299-2306
ObjectivesThe aim of this study was to compare outcomes after transcatheter aortic valve replacement (TAVR) in patients with pure aortic stenosis (AS) (i.e., no or trivial associated aortic regurgitation [AR]) with those in patients with AS and mild or more severe AR (i.e., mixed aortic valve disease [MAVD]).BackgroundTAVR is indicated in treating patients with severe AS. Limited data exist regarding the outcomes of TAVR in patients with MAVD.MethodsA total of 1,133 patients who underwent TAVR between January 2014 and December 2017 were included. The primary outcome was all-cause mortality. The comparison was adjusted to account for post-TAVR AR development in both groups. The secondary outcomes included composite endpoints of early safety and clinical efficacy as specified in the Valve Academic Research Consortium-2 criteria. Variables were compared using Mann-Whitney, chi-square, and Fisher exact tests, while Kaplan-Meier analyses were used to compare survival.ResultsA total of 688 patients (61%) had MAVD (median age 83 years , 43% women). Among these, 17% developed mild, 2% moderate, and <1% severe post-TAVR AR. Overall, patients with MAVD had better survival compared with patients with pure AS (p = 0.03). Among patients who developed post-TAVR AR, those in the MAVD group had better survival (p = 0.04). In contrast, in patients who did not develop post-TAVR AR, pre-TAVR AR did not improve survival (p = 0.11).ConclusionsPatients with MAVD who underwent TAVR had better survival compared with patients with pure AS. This is explained by the better survival of patients with MAVD who developed post-TAVR AR, likely due to left ventricular adaptation to AR. 相似文献
980.
Intrapulmonary lymph nodes (IPLNs) are a frequent finding of computed tomography for lung cancer and can grow without malignant findings. Linear densities extending from the nodules are a characteristic of IPLNs. 相似文献