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51.

Background

Cardiac time intervals have been described as a measure of cardiac performance, where prolongation, shortening and delay of the different time intervals have been evaluated as markers of cardiac dysfunction. A relatively recently developed method with improved ability to measure cardiac events is Tissue Doppler Imaging (TDI), allowing accurate measurement of myocardial movements.

Methods

We propose the state diagram of the heart as a new visualization tool for cardiac time intervals, presenting comparative, normalized data of systolic and diastolic performance, providing a more complete overview of cardiac function. This study aimed to test the feasibility of the state diagram method by presenting examples demonstrating its potential use in the clinical setting and by performing a clinical study, which included a comparison of the state diagram method with established echocardiography methods (E/E' ratio, LVEF and WMSI). The population in the clinical study consisted of seven patients with non ST-elevation myocardial infarction (NSTEMI) and seven control subjects, individually matched according to age and gender. The state diagram of the heart was generated from TDI curves from seven positions in the myocardium, visualizing the inter- and intraventricular function of the heart by displaying the cardiac phases.

Results

The clinical examples demonstrated that the state diagram allows for an intuitive visualization of pathological patterns as ischemia and dyssynchrony. Further, significant differences in percentage duration between the control group and the NSTEMI group were found in eight of the totally twenty phases (10 phases for each ventricle), e.g. in the transition phases (Pre-Ejection and Post-Ejection). These phases were significantly longer (> 2.18%) for the NSTEMI group than for the control group (p < 0.05). No significant differences between the groups were found for the established echocardiography methods.

Conclusion

The test results clearly indicate that the state diagram has potential to be an efficient tool for visualization of cardiac dysfunction and for detection of NSTEMI.  相似文献   
52.
Microtubules are a well-validated target for anticancer therapy. Molecules that bind tubulin affect dynamic instability of microtubules causing mitotic arrest of proliferating cells, leading to cell death and tumor growth inhibition. Natural antitubulin agents such as taxanes and Vinca alkaloids have been successful in the treatment of cancer; however, several limitations have encouraged the development of synthetic small molecule inhibitors of tubulin function. We have previously reported the discovery of two novel chemical series of tubulin polymerization inhibitors, triazoles (Ouyang et al. Synthesis and structure-activity relationships of 1,2,4-triazoles as a novel class of potent tubulin polymerization inhibitors. Bioorg Med Chem Lett. 2005; 15:5154-5159) and oxadiazole derivatives (Ouyang et al. Oxadiazole derivatives as a novel class of antimitotic agents: synthesis, inhibition of tubulin polymerization, and activity in tumor cell lines. Bioorg Med Chem Lett. 2006; 16:1191-1196). Here, we report on the anticancer effects of a lead oxadiazole derivative in vitro and in vivo. In vitro, IMC-038525 caused mitotic arrest at nanomolar concentrations in epidermoid carcinoma and breast tumor cells, including multidrug-resistant cells. In vivo, IMC-038525 had a desirable pharmacokinetic profile with sustained plasma levels after oral dosing. IMC-038525 reduced subcutaneous xenograft tumor growth with significantly greater efficacy than the taxane paclitaxel. At efficacious doses, IMC-038525 did not cause substantial myelosuppression or peripheral neurotoxicity, as evaluated by neutrophil counts and changes in myelination of the sciatic nerve, respectively. These data indicate that IMC-038525 is a promising candidate for further development as a chemotherapeutic agent.  相似文献   
53.
Systems analysis of iron metabolism: the network of iron pools and fluxes   总被引:1,自引:0,他引:1  

Background  

Every cell of the mammalian organism needs iron as trace element in numerous oxido-reductive processes as well as for transport and storage of oxygen. The very versatility of ionic iron makes it a toxic entity which can catalyze the production of radicals that damage vital membranous and macromolecular assemblies in the cell. The mammalian organism maintains therefore a complex regulatory network of iron uptake, excretion and intra-body distribution. Intracellular regulation in different cell types is intertwined with a global hormonal signalling structure. Iron deficiency as well as excess of iron are frequent and serious human disorders. They can affect every cell, but also the organism as a whole.  相似文献   
54.
Oral and oropharyngeal squamous cell carcinomas (OSCC) are among the most common cancers worldwide, with approximately 60% 5-yr survival rate. To identify potential markers for disease progression, we used Affymetrix U133 plus 2.0 arrays to examine the gene expression profiles of 167 primary tumor samples from OSCC patients, 58 uninvolved oral mucosae from OSCC patients and 45 normal oral mucosae from patients without oral cancer, all enrolled at one of the three University of Washington-affiliated medical centers between 2003 to 2008. We found 2,596 probe sets differentially expressed between 167 tumor samples and 45 normal samples. Among 2,596 probe sets, 71 were significantly and consistently up- or down-regulated in the comparison between normal samples and uninvolved oral samples and between uninvolved oral samples and tumor samples. Cox regression analyses showed that 20 of the 71 probe sets were significantly associated with progression-free survival. The risk score for each patient was calculated from coefficients of a Cox model incorporating these 20 probe sets. The hazard ratio (HR) associated with each unit change in the risk score adjusting for age, gender, tumor stage, and high-risk HPV status was 2.7 (95% CI: 2.0–3.8, p = 8.8E-10). The risk scores in an independent dataset of 74 OSCC patients from the MD Anderson Cancer Center was also significantly associated with progression-free survival independent of age, gender, and tumor stage (HR 1.6, 95% CI: 1.1–2.2, p = 0.008). Gene Set Enrichment Analysis showed that the most prominent biological pathway represented by the 71 probe sets was the Integrin cell surface interactions pathway. In conclusion, we identified 71 probe sets in which dysregulation occurred in both uninvolved oral mucosal and cancer samples. Dysregulation of 20 of the 71 probe sets was associated with progression-free survival and was validated in an independent dataset.  相似文献   
55.
The development of T cell tolerance directed toward tumor-associated Ags can limit the repertoire of functional tumor-reactive T cells, thus impairing the ability of vaccines to elicit effective antitumor immunity. Adoptive immunotherapy strategies using ex vivo expanded tumor-reactive effector T cells can bypass this problem; however, the susceptibility of effector T cells to undergoing tolerization suggests that tolerance might also negatively impact adoptive immunotherapy. Nonetheless, adoptive immunotherapy strategies can be effective, particularly those utilizing the drug cyclophosphamide (CY) and/or exogenous IL-2. In the current study, we used a TCR-transgenic mouse adoptive transfer system to assess whether CY plus IL-2 treatment rescues effector CD4 cell function in the face of tolerizing Ag (i.e., cognate parenchymal self-Ag). CY plus IL-2 treatment not only enhances proliferation and accumulation of effector CD4 cells, but also preserves the ability of these cells to express the effector cytokine IFN-gamma (and to a lesser extent TNF-alpha) in proportion to the level of parenchymal self-Ag expression. When administered individually, CY but not IL-2 can markedly impede tolerization, although their combination is the most effective. Although effector CD4 cells in CY plus IL-2-treated self-Ag-expressing mice eventually succumb to tolerization, this delay results in an increased level of in situ IFN-gamma expression in cognate Ag-expressing parenchymal tissues as well as death via a mechanism that requires direct parenchymal Ag presentation. These results suggest that one potential mechanism by which CY and IL-2 augment adoptive immunotherapy strategies to treat cancer is by impeding the tolerization of tumor-reactive effector T cells.  相似文献   
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Increase in obesity rates and obesity associated health issues became one of the greatest health concerns in the present world population. With alarming increase in obese percentage there is a need to design new drugs related to the obesity targets. Among the various targets linked to obesity, pancreatic lipase was one of the promising targets for obesity treatment. Using the in silico methods like structure based virtual screening, QikProp, docking studies and binding energy calculations three molecules namely zinc85531017, zinc95919096 and zinc33963788 from the natural database were reported as the potential inhibitors for the pancreatic lipase. Among them zinc95919096 presented all the interactions matching to both standard and crystal ligand and hence it can be further proceeded to drug discovery process.  相似文献   
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