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51.
The gas chromatography mass spectrometry (GCMS) with combination of Solid Phase Micro-extraction (SPME) was used to study the volatile organic compounds (VOCs) which emitted by the in-vitro cultured human cells and compared with documented volatile biomarker of lung cancer. For this purpose, the lung cancer cell (A549) and non-cancerous lung cell (WI38VA13) were cultured in identical growth medium, concurrently. The VOCs in the headspace of the cell cultures and the blank growth media (reference sample) were collected directly from the culture flask using SPME for 15minutes. The results show that two different volatile metabolites were screened out between A549 cells and Wi38VA13 cells. A549 cell found to emit 2 noticeable VOC which are decane and heneicosane. While for WI38VA13, the VOCs released were 1-Heptanol and heptadecane. The acquired VOCs were compared with the previous studies. The findings in this work conclude that the specific VOC of cells can be act as their odour signature and can be used to provide non-invasively screening of lung cancer using gas array sensor devices. 相似文献
52.
Xu M Ye J Yang D Xu X Yeo TT Ng WH Lim CC 《Analytical and bioanalytical chemistry》2007,389(7-8):2153-2159
Ex-vivo and in-vitro nuclear magnetic resonance (NMR) spectroscopy techniques have been used for studying chemical metabolites
in surgically resected specimens of human neoplasms, and may provide complementary information to in-vivo whole-body magnetic-resonance
spectroscopy (MRS). We describe an ex-vivo NMR in water method for measurement of water-soluble metabolites in unprocessed
normal rat brain tissue and human intracranial neoplasms. The NMR spectra obtained using the method described here were comparable
to those obtained using high-resolution magic-angle spinning (HRMAS) NMR methods, with good correlation in metabolite concentrations
relative to creatine (r
2 = 0.7635). Improved spectral resolution and baseline were noted compared to HRMAS, but macromolecule resonances were not
detected. Ex-vivo NMR of unprocessed tissue in water is rapid and technically simple to perform, and has the potential to
be used for direct assessment of intracranial neoplasms. 相似文献
53.
Robert Thayer Sataloff Janette C. Ressue Melissa Portell Ronald M. Harris Robert Ossoff Albert L. Merati Steven Zeitels 《Journal of voice》2000,14(1):119-134
Granular cell tumor is a rare neoplasm that may involve the larynx. It is almost always benign. Laryngologists should be familiar with this unusual tumor, its implications and appropriate treatment. 相似文献
54.
An important unsolved problem in medical science concerns the physical origin of the sigmoidal shape of pressure-volume curves of healthy (and some unhealthy) lungs. Conventional wisdom holds that linear response, i.e., Hooke’s law, together with alveolar overdistention play a dominant role in respiration, but such assumptions cannot explain the crucial empirical sigmoidal shape of the curves. Here, we propose a theory of alveolar recruitment together with nonlinear elasticity of the alveoli. The proposed model surprisingly and correctly predicts the observed sigmoidal pressure-volume curves. We discuss the importance of this result and its implications for medical practice. 相似文献
55.
We have developed a microfluidic gradient device for controlling mucin gene expression of NCI-H292 epithelial cells derived from lung tissues. We hypothesized that gradient profiles would control mucin gene expression of lung epithelial cells. However, it was not possible to generate various stable gradient profiles using conventional culture methods. To address this limitation, we used a microfluidic gradient device to create various gradient profiles (i.e. non-linear, linear, and flat) in a temporal and spatial manner. NCI-H292 lung epithelial cells were exposed to concentration gradients of epidermal growth factor in a microfluidic gradient device with continuous medium perfusion. We demonstrated an effect of gradient profiles on mucin expression of lung epithelial cells cultured in the microfluidic gradient device. It was revealed that NCI-H292 lung epithelial cells exposed to the flat gradient profile of the epidermal growth factor exhibited high expression of mucin as compared with cells exposed to non-linear and linear gradient profiles. Therefore, this microfluidic gradient device could be a potentially useful tool for regulating the mucin expression of lung epithelial cells exposed to chemokine gradient profiles. 相似文献
56.
Radiotherapy, frequently used for treatment of solid tumors, carries two main obstacles including acquired radioresistance in cancer cells during radiotherapy and normal tissue injury. Phenylpropanoids, which are naturally occurring phytochemicals found in plants, have been identified as potential radiotherapeutic agents due to their anti-cancer activity and relatively safe levels of cytotoxicity. Various studies have proposed that these compounds could not only sensitize cancer cells to radiation resulting in inhibition of growth and cell death but also protect normal cells against radiation-induced damage. This review is intended to provide an overview of recent investigations on the usage of phenylpropanoids in combination with radiotherapy in cancer treatment. 相似文献
57.
Kwak IH Shin YH Kim M Cha HY Nam HJ Lee BS Chaudhary SC Pai KS Lee JH 《Experimental & molecular medicine》2011,43(2):111-120
Aberrant activation of hepatocyte growth factor/scatter factor (HGF/SF) and its receptor, Met, is involved in the development and progression of many human cancers. In the cell-based screening assay, (-)epigallocatechin-3-gallate (EGCG) inhibited HGF/SF-Met signaling as indicated by its inhibitory activity on HGF/SF-induced cell scattering and uPA activation (IC50=15.8 microgram/ml). Further analysis revealed that EGCG at low doses specifically inhibited HGF/SF-induced tyrosine phosphorylation of Met but not epidermal growth factor (EGF)-induced phosphorylation of EGF receptor (EGFR). On the other hand, high-dose EGCG decreased both Met and EGFR proteins. We also found that EGCG did not act on the intracellular portion of Met receptor tyrosine kinase, i.e., it inhibited InlB-dependent activation of Met but not NGF-induced activation of Trk-Met hybrid receptor. This inhibition decreased HGF-induced migration and invasion by parental or HGF/SF-transfected B16F10 melanoma cells in vitro in either a paracrine or autocrine manner. Furthermore, EGCG inhibited the invasion/metastasis of HGF/SF-transfected B16F10 melanoma cells in mice. Our data suggest the possible use of EGCG in human cancers associated with dysregulated paracrine or autocrine HGF/SF-Met signaling. 相似文献
58.
Min Hee Lee So Ri Kim Seung Yong Park Seoung Ju Park Eun Jung Lee Gong Yong Jin Yong Chul Lee 《Magnetic resonance imaging》2012
Although some therapeutics provide an opportunity for cure, recurrence is a major obstacle to achieve a complete remission for lung cancers. Therefore, precise assessment of lung cancers has been a task with challenge. In recent years, integration of positron emission tomography and computed tomography (PET–CT) and whole-body magnetic resonance imaging (WB-MRI) have been introduced as an alternative to standard multimodality imaging strategies and are now increasingly applied to various malignancies. However, there is little information on the surveillance capability of WB-MRI in patients with lung cancers. We aimed to investigate the clinical potential of WB-MRI as a novel surveillance modality after curative treatments for lung cancers, comparing it with PET–CT. Sixty two consecutive patients with lung malignancy who underwent both WB-MRI and PET–CT were selected to assess the recurrent malignant lesions. The clinical data including radiologic and pathologic findings were collected and analyzed retrospectively. On each lymph node station, the ability of WB-MRI to detect malignant lesions significantly correlated with that of PET–CT (γ= 0.86; P<.01). The correlation coefficient ranged from 0.999 to 1 for assessing distant metastases from lung cancers by two modalities (P<.01). Based on the pathologic confirmation, both modalities showed an equivalent diagnostic accuracy (PET–CT: sensitivity 85.71%, specificity 47.27% versus WB-MRI: sensitivity 85.71%, specificity 56.25%). This study demonstrates the clinical potential of WB-MRI, together with PET–CT, as a novel surveillance modality for lung cancers after curative treatments. 相似文献
59.
利用体内噬菌体展示技术筛选了肿瘤特异性结合靶肽, 获得了肺腺癌靶肽CSIHYPLSC(YC11)并对其进行了放射性碘标记. 采用反相高效液相色谱技术(RP-HPLC)分离纯化131I-YC11和对照肽131I-NGR, 放化纯度大于99%. 在荷人肺腺癌A549裸鼠体内的分布结果表明, 131I-YC11的肿瘤/血液放射性计数比为0.62, 肿瘤/心脏放射性计数比为2.06, 肿瘤/肺放射性计数比为1.11, 肿瘤/肝脏放射性计数比为0.81, 略高于131I-NGR的对应值. 131I-YC11在肿瘤中的摄取值为2.79%ID/g, 与131I-NGR在肿瘤中的摄取值(1.61%ID/g)相比, 131I-YC11的肿瘤摄取高于多肽131I-NGR. 相似文献
60.
Jaime F. Mata Talissa A. AltesKai Ruppert Klaus D. HagspielGrady W. Miller James R. BrookemanJohn P. Mugler III 《Magnetic resonance imaging》2009
The purpose of this study was to assess the properties of a model system for hyperpolarized He-3 (HHe) diffusion MR imaging created from the lungs of New Zealand white rabbits by drying the lungs while inflated at constant pressure. The dried lungs were prepared by sacrificing the animal, harvesting the lungs en bloc and dehydrating the lungs for several days using dry compressed air. In four rabbits, the apparent diffusion coefficient (ADC) of HHe gas was measured in vivo and, within 1 week, in vitro in the dried lungs. To assess long-term repeatability, in vitro ADC values were measured again 3 months later. Dried lungs from four additional rabbits were imaged twice on the same day to assess the short-term repeatability of ADC measurements, and tissue samples from these lungs were then removed for histology. In vivo and in vitro ADC maps showed similar features and similar distributions of ADC values; mean in vivo and in vitro ADC values differed by less than 12%. The in vitro mean ADC values were highly reproducible, with no more than 5% difference between measurements for the short-term repeatability and less than 17% difference between measurements for the long-term repeatability. Histological samples from the dried lungs demonstrated that the lung structure remained intact. These results suggest that the dried lungs are a useful and inexpensive alternative to human or in vivo animal studies for HHe diffusion MR sequence development, testing and optimization. 相似文献