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1.
《Diagnostic and interventional imaging》2020,101(12):821-830
PurposeTo compare morphological imaging features and CT texture histogram parameters between grade 3 pancreatic neuroendocrine tumors (G3-NET) and neuroendocrine carcinomas (NEC).Materials and methodsPatients with pathologically proven G3-NET and NEC, according to the 2017 World Health Organization classification who had CT and MRI examinations between 2006-2017 were retrospectively included. CT and MRI examinations were reviewed by two radiologists in consensus and analyzed with respect to tumor size, enhancement patterns, hemorrhagic content, liver metastases and lymphadenopathies. Texture histogram analysis of tumors was performed on arterial and portal phase CT images. images. Morphological imaging features and CT texture histogram parameters of G3-NETs and NECs were compared.ResultsThirty-seven patients (21 men, 16 women; mean age, 56 ± 13 [SD] years [range: 28-82 years]) with 37 tumors (mean diameter, 60 ± 46 [SD] mm) were included (CT available for all, MRI for 16/37, 43%). Twenty-three patients (23/37; 62%) had NEC and 14 patients (14/37; 38%) had G3-NET. NECs were larger than G3-NETs (mean, 70 ± 51 [SD] mm [range: 18 - 196 mm] vs. 42 ± 24 [SD] mm [range: 8 - 94 mm], respectively; P = 0.039), with more tumor necrosis (75% vs. 33%, respectively; P = 0.030) and lower attenuation on precontrast (30 ± 4 [SD] HU [range: 25-39 HU] vs. 37 ± 6 [SD] [range: 25-45 HU], respectively; P = 0.002) and on portal venous phase CT images (75 ± 18 [SD] HU [range: 43 - 108 HU] vs. 92 ± 19 [SD] HU [range: 46 - 117 HU], respectively; P = 0.014). Hemorrhagic content on MRI was only observed in NEC (P = 0.007). The mean ADC value was lower in NEC ([1.1 ± 0.1 (SD)] × 10−3 mm2/s [range: (0.91 - 1.3) × 10−3 mm2/s] vs. [1.4 ± 0.2 (SD)] × 10−3 mm2/s [range: (1.1 - 1.6) × 10−3 mm2/s]; P = 0.005). CT histogram analysis showed that NEC were more heterogeneous on portal venous phase images (Entropy-0: 4.7 ± 0.2 [SD] [range: 4.2-5.1] vs. 4.5 ± 0.4 [SD] [range: 3.7-4.9]; P = 0.023).ConclusionPancreatic NECs are larger, more frequently hypoattenuating and more heterogeneous with hemorrhagic content than G3-NET on CT and MRI. 相似文献
2.
Daniel A. Monti Marie E. Stoner Gail Zivin Martha Schlesinger 《Journal of cancer survivorship》2007,1(2):161-166
Introduction As many as one quarter of all cancer survivors report traumatic stress symptoms from cancer-related experiences. While the
majority of these patients do not meet the criteria for posttraumatic stress disorder (PTSD), there is growing evidence that
subsyndromal symptoms can significantly contribute to functional impairment and negative health outcomes. Treatment options
for the hallmark symptoms of traumatic stress—unpleasant, intrusive thoughts and avoidant behaviors—have not been well investigated
for the cancer survivorship population.
Materials and methods Seven female cancer survivors with traumatic stress symptoms from cancer-related experiences and no other major psychopathology,
were enrolled to receive three sessions of Neuro-Emotional Technique (NET), a brief, targeted treatment that combines traditional
desensitization principles with complementary modalities.
Results Psychological outcome measures (Impact of Event Scale (IES) and Subjective Units of Distress (SUD) and physiological measures
(Heart Rate (HR) and Skin Conductance Level (SCL) demonstrated the following changes: 71% on IES, 88% SUD, 74% on HR, and
65% on SCL following the intervention. Statistically significant changes were observed for all four parameters, and effect
size g for proportion improved were 0.50 each for IES, SUD, and HR, and 0.20 for SCL.
Conclusions These cases suggest feasibility of the NET intervention for cancer-related traumatic stress and the potential for change in
symptoms and physiological reactivity. Further investigation is needed to determine the specific and long-term effects of
such an approach.
Implications for cancer survivors Traumatic stress from cancer-related experiences might represent a constellation of symptoms that are amenable to brief, targeted
interventions.
This study was supported by the O.N.E. Research Foundation 相似文献
3.
Isolation and partial characterization of the tegumental outer membrane of schistosomula of Schistosoma mansoni 总被引:1,自引:0,他引:1
F Levi-Schaffer R Tarrab-Hazdai M D Schryer R Arnon M Smolarsky 《Molecular and biochemical parasitology》1984,13(3):283-300
Separation of the external membranes from freshly converted mechanical schistosomula of Schistosoma mansoni was achieved by osmotic shock under hypertonic conditions, followed by mechanical shearing and ultracentrifugation. Prior to treatment, the schistosomula were surface labeled by introduction of N-DNP-epsilon-aminocaproylphosphatidylethanolamine molecules into their lipid bilayer followed by anti-DNP antibodies and stained with either 125I-protein-A or ferritin labeled secondary anti-DNP antibodies. This label provided a membrane marker by which the purity of the preparation could be assessed at each stage. Fluorescence staining with FITC-conjugated secondary antibodies prior to treatment revealed that the homogeneously stained membrane of the intact schistosomula became swollen and ruptured after the osmotic shock. The isolated membrane pellet was intensely fluorescent. Electron microscopical examination revealed mostly vesicles, some of them with organized multilayer assembly. The vesicles were ferritin labeled, indicating that they originated from the outer surface membrane of the schistosomula. A 100 fold enrichment in the alkaline phosphatase activity and about 300 fold enrichment in acetylcholinesterase activity in the membrane preparations, as compared to the intact schistosomula, was found. The isolated tegument was analyzed by SDS-polyacrylamide gel electrophoresis. The pattern obtained showed three major bands, of molecular weights 69 000, 45 000 and 12 000 alongside with a large number of minor bands. Immunoprecipitation of the isolated 125I-labeled membrane antigens with antisera from chronically infected mice revealed these three major bands together with three other bands of molecular weight 38 000, 23 000 and 16 000. 相似文献
4.
Neutrophil extracellular traps play a key role in defense against extracellular pathogens. The release of these chromatin structures, that contain a combination of cytoplasmic and granule proteins, is known as NETosis, a regulated cell death modality typical of neutrophils. NETosis is induced by pathogens as well as other stimuli such as activated platelets. Our understanding of the molecular events underlying this phenomenon remains incomplete. The currently used experimental approaches to study NETs are semi‐quantitative, subjective in nature, and low throughput, rendering it difficult to compare results between laboratories. This is highlighted in two articles published in this issue of the European Journal of Immunology which present what appear to be contradicting results on NET formation. Considering the extensive research on NETosis and the importance of this phenomenon in the immune response, we find it timely to briefly review the lacunae in the most commonly used methods to investigate NETosis. The impact these technical difficulties have on the advancement of our knowledge in this field as well as potential solutions are also discussed. 相似文献
5.
6.
Meredith Bryarly Lauren T. Phillips Qi Fu Steven Vernino Benjamin D. Levine 《Journal of the American College of Cardiology》2019,73(10):1207-1228
Postural orthostatic tachycardia syndrome (POTS), the most common form of orthostatic intolerance in young people, affects approximately 500,000 people in the United States alone, typically young women at the peak of their education and the beginning of their working lives. This is a heterogeneous disorder, the pathophysiology and mechanisms of which are not well understood. There are multiple contributing factors and numerous potential mimics. This review details the most current views on the potential causes, comorbid conditions, proposed subtypes, differential diagnoses, evaluations, and treatment of POTS from cardiological and neurological perspectives. 相似文献
7.
Primary cutaneous neuroendocrine tumors (NET) except for Merkel cell carcinoma have rarely been reported. Herein reported is a very unique case of primary cutaneous NET with immunohistochemical markers of myoepitheliomas. A 47-year-old woman presented a tumor measuring 0.8x0.9x0.6 cm of the face. The tumor was excised completely with wide margins. Morphologically, the tumor was located in the dermis, and the tumor was composed of epithelioid cells arranged in trabecular, sinusoidal, rosette, ribbon-like, and cord-like patterns. Focal areas show tubular formations. The tumor cells were homogenous, and their nuclei showed hyperchromasia but no apparent histological features of malignancy were seen. The stroma was very scant. No invasive features were seen. Immunohistochemically, the tumor cells were strongly positive for cytokeratin (CK) 34BE12, CD5/6, CK14, NCAM (CD56), p63, and KIT (CD117), and moderately positive for CK AE1/3, p53, chromogranin, synaptophysin, neuron-specific enolase (NSE), PDGFRA, CA19-9, and Ki-67 antigen (labeling index=23%). The tumor cells were negative for CK CAM5.2, CK7, CK8, CK18,CK19,CK20, EMA, vimentin, CEA, HMB45, S100 protein, α-smooth muscle antigen, desmin, CD34, GFAP, neurofilaments, CD99 (MIC2), CD45, CD57, ErbB2, TTF-1, MUC1, MUC2, MUC5AC, and MUC6. Mucins examined by d-PAS and Alcian blue techniques were negative. A genetic analysis using PCR-direct sequencing method in paraffin sections identified no mutations of KIT (exons 9, 11, 13 and 17) and PDGFRA (exons 12 and 18) genes. Imaging modalities including CT and MRI identified no tumor in the body. The clinicians thought that the tumor was cured. She was a sailor and immediately visited other countries; therefore the follow-up could not be done. 相似文献
8.
Somatostatin is a peptide with a potent and broad antisecretory action, which makes it an invaluable drug target for the pharmacological management of pituitary adenomas and neuroendocrine tumors. Somatostatin receptors (SSTR1, 2A and B, 3, 4 and 5) belong to the G protein coupled receptor family and have a wide expression pattern in both normal tissues and solid tumors. Investigating the function of each SSTR in several tumor types has provided a wealth of information about the common but also distinct signaling cascades that suppress tumor cell proliferation, survival and angiogenesis. This provided the rationale for developing multireceptor-targeted somatostatin analogs and combination therapies with signaling-targeted agents such as inhibitors of the mammalian (or mechanistic) target of rapamycin (mTOR). The ability of SSTR to internalize and the development of rabiolabeled somatostatin analogs have improved the diagnosis and treatment of neuroendocrine tumors. 相似文献
9.
Elvia Mena-Avila Ricardo Márquez-Gómez Guillermo Aquino-Miranda Gustavo Nieto-Alamilla José-Antonio Arias-Montaño 《Pharmacological reports : PR》2018,70(1):146-155
Background
Clobenpropit, a potent antagonist/inverse agonist at the histamine H3 receptor (H3R), reduced the cytotoxic action of 6-hydroxydopamine (6-OHDA) in neuroblastoma SH-SY5Y cells transfected with the human H3R. We therefore set out to study whether this effect involved a receptor-independent action on dopamine transport.Methods
The uptake of [3H]-dopamine was assayed in SH-SY5Y cells and rat striatal or cerebro-cortical isolated nerve terminals (synaptosomes). Clobenpropit binding to the human norepinephrine (NET) and dopamine (DAT) transporters was analyzed by molecular modeling.Results
In SH-SY5Y cells, [3H]-dopamine uptake was inhibited by desipramine (selective NET inhibitor), GBR-12909 (selective DAT inhibitor), and fluoxetine (selective inhibitor of the serotonin transporter, SERT) with IC50 values 37, 537, and 2800 nM, respectively. The potency rank order indicates that [3H]-dopamine uptake is primarily performed by NET. Clobenpropit inhibited [3H]-dopamine uptake (maximum inhibition 82.7 ± 2.8%, IC50 490 nM), and the effect was reproduced by the H3R antagonist/inverse agonist iodophenpropit, but not by the agonists R-α-methylhistamine and immepip or the antagonists/inverse agonists ciproxifan and A-331440. Clobenpropit also inhibited [3H]-dopamine uptake by rat striatal and cerebro-cortical synaptosomes (?54.6 ± 11.3% and ?46.3 ± 9.6%, respectively, at 10 μM). Modeling of the human NET and DAT obtained by homology from the crystal of Drosophila melanogaster DAT showed that clobenpropit can bind to a site also recognized in both transporters by nisoxetine, a potent NET inhibitor.Conclusion
These data indicate a direct inhibitory effect of clobenpropit on catecholamine transport. 相似文献10.
目的:开发设计一种远程网络设备管理软件,解决医院网络设备管理手段落后的问题.方法:采用模块化思想和可视化管理,应用.NET程序设计,基于telnet协议,利用网络设备固定命令,实现远程管理功能.结果:经在医院网络中测试运行,实现了网络交换机管理、备份和恢复配置程序、显示接口运行状态等服务,满足了网管人员的基本需求.结论:该系统平台为管理人员提供了方便快捷的可视化服务,同时,减少了维护人员的工作量,提升了工作效率,对医院网络管理智能化起到了推动作用,具有一定的应用和推广价值. 相似文献