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101.
Yang Y Macleod V Bendre M Huang Y Theus AM Miao HQ Kussie P Yaccoby S Epstein J Suva LJ Kelly T Sanderson RD 《Blood》2005,105(3):1303-1309
Although widespread skeletal dissemination is a critical step in the progression of myeloma, little is known regarding mechanisms that control metastasis of this cancer. Heparanase-1 (heparanase), an enzyme that cleaves heparan sulfate chains, is expressed at high levels in some patients with myeloma and promotes metastasis of some tumor types (eg, breast, lymphoma). Using a severe combined immunodeficient (SCID) mouse model, we demonstrate that enhanced expression of heparanase by myeloma cells dramatically up-regulates their spontaneous metastasis to bone. This occurs from primary tumors growing subcutaneously and also from primary tumors established in bone. Interestingly, tumors formed by subcutaneous injection of cells metastasize not only to bone, but also to other sites including spleen, liver, and lung. In contrast, tumors formed by injection of cells directly into bone exhibit a restricted pattern of metastasis that includes dissemination of tumor to other bones but not to extramedullary sites. In addition, expression of heparanase by myeloma cells (1) accelerates the initial growth of the primary tumor, (2) increases whole-body tumor burden as compared with controls, and (3) enhances both the number and size of microvessels within the primary tumor. These studies describe a novel experimental animal model for examining the spontaneous metastasis of bone-homing tumors and indicate that heparanase is a critical determinant of myeloma dissemination and growth in vivo. 相似文献
102.
Xiu-Xia Luo Fang FangAlex Pui-Wai Lee Jing-Ping SunShuang Li Zhi-Hua ZhangJohn E. Sanderson Joey S.W. KwongQing Zhang Jing WangCheuk-Man Yu 《International journal of cardiology》2014
Purpose
Three-dimensional speckle-tracking echocardiography (3D-STE) is a newly developed technique to evaluate left ventricular (LV) deformation by measuring the area strain (AS) of endocardial surface that combines information from both longitudinal (LS) and circumferential strain (CS). We performed a study to examine myocardial deformation in patients with heart failure (HF) using 3D-STE.Method
A total of 149 subjects including 58 patients with HF and preserved ejection fraction (HFPEF), 45 patients with HF and reduced ejection fraction (HFREF), and 46 normal subjects were prospectively studied by 3D-STE.Result
After adjusting for age, gender and BSA, global CS, LS, radial strain (RS) and AS derived from 3D-STE in patients with HFPEF were significantly higher than their counterparts in patients with HFREF (all p < 0.001), but lower than that in normal subjects (all p < 0.05). In addition, among all the strain parameters, global AS exhibited the highest correlation with LV ejection fraction (y = 1.243x + 6.332, r = 0.982, p < 0.001) and the best intra- (ICCs: 0.986, p < 0.001) and inter-observer variability (ICCs: 0.978, p < 0.001) than other parameters of 3D strain (CS: 0.981 and 0.974; LS: 0.908 and 0.841; RS: 0.946 and 0.915; all p < 0.001).Conclusions
Measurement of endocardial surface AS based on 3D-STE technique is reproducible and proves to be accurate and comprehensive in assessing the global LV performance and multidirectional deformation of the LV myocardium in HF patients. 相似文献103.
Elizabeth A. Laugeson Ruth Ellingsen Jennifer Sanderson Lara Tucci Shannon Bates 《Journal of autism and developmental disorders》2014,44(9):2244-2256
Social skills training is a common treatment method for adolescents with autism spectrum disorder (ASD), yet very few evidence-based interventions exist to improve social skills for high-functioning adolescents on the spectrum, and even fewer studies have examined the effectiveness of teaching social skills in the classroom. This study examines change in social functioning for adolescents with high-functioning ASD following the implementation of a school-based, teacher-facilitated social skills intervention known as Program for the Education and Enrichment of Relational Skills (PEERS ® ). Seventy-three middle school students with ASD along with their parents and teachers participated in the study. Participants were assigned to the PEERS ® treatment condition or an alternative social skills curriculum. Instruction was provided daily by classroom teachers and teacher aides for 14-weeks. Results reveal that in comparison to an active treatment control group, participants in the PEERS ® treatment group significantly improved in social functioning in the areas of teacher-reported social responsiveness, social communication, social motivation, social awareness, and decreased autistic mannerisms, with a trend toward improved social cognition on the Social Responsiveness Scale. Adolescent self-reports indicate significant improvement in social skills knowledge and frequency of hosted and invited get-togethers with friends, and parent-reports suggest a decrease in teen social anxiety on the Social Anxiety Scale at a trend level. This research represents one of the few teacher-facilitated treatment intervention studies demonstrating effectiveness in improving the social skills of adolescents with ASD in the classroom: arguably the most natural social setting of all. 相似文献
104.
Yang Y Yaccoby S Liu W Langford JK Pumphrey CY Theus A Epstein J Sanderson RD 《Blood》2002,100(2):610-617
Syndecan-1 (CD138) is a transmembrane heparan sulfate-bearing proteoglycan expressed by most myeloma plasma cells that regulates adhesion, migration, and growth factor activity. In patients with myeloma, shed syndecan-1 accumulates in the bone marrow, and high levels of syndecan-1 in the serum are an indicator of poor prognosis. To test the effect of soluble syndecan-1 on tumor cell growth and dissemination, ARH-77 B-lymphoid cells were engineered to produce a soluble form of syndecan-1. Controls included vector only (neo)-transfected cells and cells transfected with full-length syndecan-1 complementary DNA that codes for the cell surface form of syndecan-1. Assays reveal that all 3 transfectants have similar growth rates in vitro, but cells expressing soluble syndecan-1 are hyperinvasive in collagen gels relative to controls. When injected into the marrow of human bones that were implanted in severe combined immunodeficient mice, tumors formed by cells expressing soluble syndecan-1 grow faster than tumors formed by neo-transfected cells or by cells expressing cell surface syndecan-1. In addition, cells bearing cell surface syndecan-1 exhibit a diminished capacity to establish tumors within the mice as compared with both neo- and soluble syndecan-1-transfected cells. Tumor cell dissemination to a contralateral human bone is detected significantly more often in the tumors producing soluble syndecan-1 than in controls. Thus, high levels of soluble syndecan-1 present in patients with myeloma may contribute directly to the growth and dissemination of the malignant cells and thus to poor prognosis. 相似文献
105.
Pradyumna Agasthi Hasan Ashraf Sai Harika Pujari Marlene Girardo Andrew Tseng Farouk Mookadam Nithin Venepally Matthew R Buras Bishoy Abraham Banveet K Khetarpal Mohamed Allam Siva K Mulpuru MD Mackram F Eleid Kevin L Greason Nirat Beohar John Sweeney David Fortuin David R Jr Holmes Reza Arsanjani 《World journal of cardiology》2023,15(3):95-105
BACKGROUND Atrioventricular block requiring permanent pacemaker(PPM) implantation is an important complication of transcatheter aortic valve replacement(TAVR).Application of machine learning could potentially be used to predict preprocedural risk for PPM.AIM To apply machine learning to be used to predict pre-procedural risk for PPM.METHODS A retrospective study of 1200 patients who underwent TAVR(January 2014-December 2017) was performed. 964 patients without prior PPM were included for a 30-d ... 相似文献
106.
Margaret L. Kaplan Gregory M. Asnis William C. Sanderson Lata Keswani Juan M. de Lecuona Sunny Joseph 《Journal of clinical psychology》1994,50(2):294-298
This study examined whether patients disclosed the same information about suicidal behaviors on a self-report instrument that they conveyed to a clinician in a face-to-face interview. The results indicated a generally high level of agreement between these two forms of suicide assessment. The one exception was the question that concerns recent suicidal ideation, where patients tended to disclose more on the self-report form. 相似文献
107.
Twenty-two detergent cleaning solutions from different ward areas were sampled for bacteria when freshly prepared, during use and at discard. Contamination, mainly by Gram-negative bacilli, was found in 10 freshly prepared solutions and in 21 of the 22 at discard. Preliminary studies showed that the detergent solution was bactericidal to Staphylococcus aureus but allowed the survival but not multiplication of Escherichia coli. 相似文献
108.
Pomegranate is the fruit of the pomegranate tree ( Punica granatum ), native to Africa, introduced into the Mediterranean area, and now widely cultivated. The tree be-longs to the Myrtaceae family and is currently used therapeutically for gingivitis and gastric-duodenal trait. The fruit pulp is made up of a cluster of red-violet seeds. 相似文献
109.
PURPOSE: To assess the feasibility of combined perfusion and viability testing by using magnetic resonance (MR) imaging in one setting in patients with non-ST segment-elevation acute coronary syndromes. MATERIALS AND METHODS: The data of 13 patients (mean age, 68 years; range, 40-85 years) at high risk for myocardial infarction who underwent MR imaging at 1.5 T were reviewed. Risk factors were increased troponin T levels in seven, reversible ST depression on an electrocardiogram in four, history of myocardial infarction in two, and presence of heart failure in four. Cine imaging of the left ventricle was performed with a true-fast imaging with steady-state precession (FISP) sequence to assess the regional myocardial contraction and ejection fraction. After injection of 0.1 mmol per kilogram of body weight of gadopentetate dimeglumine, first-pass MR images were obtained by using an inversion-recovery true-FISP sequence at rest and during infusion of adenosine (140 microg/kg/min). Resting and stress images were assessed qualitatively for abnormal regional perfusion (hypoenhancement). The myocardium was divided into three radial segments corresponding to the three coronary artery territories. Delayed (after 15 minutes) contrast material-enhanced images were acquired with use of a segmented inversion-recovery fast low-angle shot sequence. Conventional coronary angiograms were compared with the first-pass images. A more than 50% stenosis in diameter in any coronary artery was considered substantial. Mann-Whitney test was used to assess any significant difference between the left ventricular ejection fraction (LVEF) in patients with and those without myocardial infarct. RESULTS: Mean LVEF was 51.5% (range, 30%-77%). First-pass stress perfusion studies depicted 25 segments of hypoenhancement in 11 patients. Comparison of first-pass perfusion defects with findings on coronary angiograms indicated an overall sensitivity of 92% (24 of 26) and specificity of 92% (12 of 13) in detection of substantial coronary artery disease. Infarcts detected from hyperenhancement on delayed contrast-enhanced images were present in eight segments (four were transmural) in five patients. No significant difference was noted in the LVEF between patients with and those without infarct (P =.724). CONCLUSION: Combined stress perfusion and viability MR imaging was feasible in patients with acute coronary syndromes. First-pass MR perfusion defects compare well with the presence of substantial coronary artery stenosis on conventional angiograms. 相似文献
110.
Prospective,Randomized, Sham‐Control,Double Blind,Crossover Trial of Subthreshold Spinal Cord Stimulation at Various Kilohertz Frequencies in Subjects Suffering From Failed Back Surgery Syndrome (SCS Frequency Study) 下载免费PDF全文