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Noninvasive Detection (noninvasive + detection)
Selected AbstractsCMR2009: 11.05: Noninvasive detection and biological impacts of injected single-walled carbon nanotubes (SWCNT) using MR techniquesCONTRAST MEDIA & MOLECULAR IMAGING, Issue 6 2009A. Al Faraj No abstract is available for this article. [source] Specific dynamic and noninvasive labeling of pancreatic , cells in reporter miceGENESIS: THE JOURNAL OF GENETICS AND DEVELOPMENT, Issue 4 2005Ahmi Ben-Yehudah Abstract Noninvasive detection of differentiated cells is increasingly demanded for accurate and reliable assessments of both in vitro and in vivo experimental systems. Here we present an efficient, innovative approach for imaging the , cells of the pancreatic islets of Langerhans. The main physiologic function of , cells is glucose-stimulated insulin secretion. This function is facilitated through the synthesis and storage of insulin in secretory vesicles of , cells, which then release their contents when , cells are exposed to hyperglycemic conditions. To visualize , cells in vivo in the mouse, we used targeted mutagenesis techniques to construct a modified insulin II (InsII) gene allele, InsIIEGFP, that expresses a proinsulin-EGFP (enhanced green fluorescent protein) fusion peptide. The EGFP portion of this fusion is entirely within the C-peptide portion of the proinsulin peptide. This fusion protein is processed in , cells to insulin and EGFP-tagged C peptide, which are stored together in cytoplasmic secretory vesicles. The large amount of vesicular EGFP-tagged C peptide is evident as a characteristic robust and specific fluorescence pattern in the , cells of InsIIEGFP mice. This innovative method of visualizing , cells will be a useful tool in the study of both , cell physiology and the development of the endocrine cells of the pancreas.genesis 43:166,174, 2005. © 2005 Wiley-Liss, Inc. [source] Noninvasive detection of pulmonary tissue destruction in a mouse model of emphysema using hyperpolarized 129Xe MRS under spontaneous respirationMAGNETIC RESONANCE IN MEDICINE, Issue 4 2010Hirohiko Imai Abstract In the present study, a chemical shift saturation recovery method in hyperpolarized 129Xe MR spectroscopy measurements was applied to two groups of spontaneously breathing mice, an elastase-induced emphysema model and a control group. Parameters detected were those related to lung structures and functions, such as alveolar septal thickness, h, the ratio of the alveolar septal volume relative to gas space volume, Vs/Va, and the transit time of blood through the gas exchange region, ,. To investigate the potential of these parameters as biomarkers, an attempt was made to detect physiologic changes in the lungs of elastase-treated mice. Our results showed that Vs/Va was significantly reduced in elastase-treated mice, reflecting emphysema-like destruction of the alveolar wall. Compared with histologic results, this degree of reduction was shown to reflect the severity of wall destruction. On the other hand, significant changes in other parameters, h and ,, were not shown. This study is the first application of hyperpolarized 129Xe MR spectroscopy to a mouse model of emphysema and shows that the Vs/Va volume ratio is an effective biomarker for emphysema that could become useful in drug research and development through noninvasive detection of pathologic changes in small rodents. Magn Reson Med, 2010. © 2010 Wiley-Liss, Inc. [source] Urinary biomarker profiling in transitional cell carcinomaINTERNATIONAL JOURNAL OF CANCER, Issue 11 2006Nicholas P. Munro Abstract Urinary biomarkers or profiles that allow noninvasive detection of recurrent transitional cell carcinoma (TCC) of the bladder are urgently needed. We obtained duplicate proteomic (SELDI) profiles from 227 subjects (118 TCC, 77 healthy controls and 32 controls with benign urological conditions) and used linear mixed effects models to identify peaks that are differentially expressed between TCC and controls and within TCC subgroups. A Random Forest classifier was trained on 130 profiles to develop an algorithm to predict the presence of TCC in a randomly selected initial test set (n = 54) and an independent validation set (n = 43) several months later. Twenty two peaks were differentially expressed between all TCC and controls (p < 10,7). However potential confounding effects of age, sex and analytical run were identified. In an age-matched sub-set, 23 peaks were differentially expressed between TCC and combined benign and healthy controls at the 0.005 significance level. Using the Random Forest classifier, TCC was predicted with 71.7% sensitivity and 62.5% specificity in the initial set and with 78.3% sensitivity and 65.0% specificity in the validation set after 6 months, compared with controls. Several peaks of importance were also identified in the linear mixed effects model. We conclude that SELDI profiling of urine samples can identify patients with TCC with comparable sensitivities and specificities to current tumor marker tests. This is the first time that reproducibility has been demonstrated on an independent test set analyzed several months later. Identification of the relevant peaks may facilitate multiplex marker assay development for detection of recurrent disease. © 2006 Wiley-Liss, Inc. [source] Noninvasive detection of pulmonary tissue destruction in a mouse model of emphysema using hyperpolarized 129Xe MRS under spontaneous respirationMAGNETIC RESONANCE IN MEDICINE, Issue 4 2010Hirohiko Imai Abstract In the present study, a chemical shift saturation recovery method in hyperpolarized 129Xe MR spectroscopy measurements was applied to two groups of spontaneously breathing mice, an elastase-induced emphysema model and a control group. Parameters detected were those related to lung structures and functions, such as alveolar septal thickness, h, the ratio of the alveolar septal volume relative to gas space volume, Vs/Va, and the transit time of blood through the gas exchange region, ,. To investigate the potential of these parameters as biomarkers, an attempt was made to detect physiologic changes in the lungs of elastase-treated mice. Our results showed that Vs/Va was significantly reduced in elastase-treated mice, reflecting emphysema-like destruction of the alveolar wall. Compared with histologic results, this degree of reduction was shown to reflect the severity of wall destruction. On the other hand, significant changes in other parameters, h and ,, were not shown. This study is the first application of hyperpolarized 129Xe MR spectroscopy to a mouse model of emphysema and shows that the Vs/Va volume ratio is an effective biomarker for emphysema that could become useful in drug research and development through noninvasive detection of pathologic changes in small rodents. Magn Reson Med, 2010. © 2010 Wiley-Liss, Inc. [source] Potential impact of a new blood glucose monitoring device: the GlucoWatch® BiographerPRACTICAL DIABETES INTERNATIONAL (INCORPORATING CARDIABETES), Issue 4 2002NN Chan Abstract Home blood glucose monitoring may be laborious, time-consuming, inconvenient and painful. Failure to test may preclude optimisation of glycaemic control. We aimed to evaluate the potential usefulness of a new noninvasive automatic glucose monitor, the GlucoWatch® Biographer. Eight patients with type 1 diabetes and two with type 2 diabetes (4M:6F) aged between 23 and 65 years participated in this study. All participants were given 1 hour of instruction prior to provision of the GlucoWatch®. They were given contact numbers and reviewed weekly. Several disadvantages were encountered by the participants, which included the daily 3 hour calibration period (n = 10), skin irritations (n = 6) and skipped measurements (n = 2) due to unsatisfactory probe contact due to skin temperature or sweats. Several patients, however, found it invaluable to have their daily profile monitored to allow insulin dosage adjustment and detection of hypoglycaemia. The GlucoWatch® Biographer is an invaluable tool that allows noninvasive detection of glucose trends, which contributes to glycaemic control. However, it is not suitable for every patient. Self-motivation and ability to learn how to use the device are the key factors. Copyright © 2002 John Wiley & Sons, Ltd. [source] A microarray-based approach for the identification of epigenetic biomarkers for the noninvasive diagnosis of fetal diseasePRENATAL DIAGNOSIS, Issue 11 2009Tianjiao Chu Abstract Objectives We describe a novel microarray-based approach for the high-throughput discovery of epigenetic biomarkers for use in the noninvasive detection of fetal genetic disease. Methods We combined a 215 060-probe custom oligonucleotide microarray with a comprehensive library preparation method and novel statistical tools to compare DNA methylation patterns in chorionic villus samples (CVS) with gestational age-matched maternal blood cell (MBC) samples. Our custom microarray was designed to provide high-resolution coverage across human chromosomes 13, 18 and 21. Results We identified 6311 MspI/HpaII sites across all three chromosomes that displayed tissue-specific differential CpG methylation patterns. To maximize the probability of identifying biomarkers that have clinical utility we filtered our data to identify MspI/HpaII sites that are within 150 bp of a highly polymorphic single nucleotide polymorphism (SNP) so that its allelic ratio may be determined for the detection of fetal aneuploidy. Our microarray design and the computational tools used for data analysis are available for download as is the entire data set. Conclusions This high-resolution analysis of DNA methylation patterns in the human placenta during the first trimester of pregnancy identifies numerous potential biomarkers for the diagnosis of fetal aneuploidy on chromosomes 13, 18 and 21. Copyright © 2009 John Wiley & Sons, Ltd. [source] Digital PCR: a powerful new tool for noninvasive prenatal diagnosis?PRENATAL DIAGNOSIS, Issue 12 2008Bernhard G. Zimmermann Abstract Recent reports have indicated that digital PCR may be useful for the noninvasive detection of fetal aneuploidies by the analysis of cell-free DNA and RNA in maternal plasma or serum. In this review we provide an insight into the underlying technology and its previous application in the determination of the allelic frequencies of oncogenic alterations in cancer specimens. We also provide an indication of how this new technology may prove useful for the detection of fetal aneuploidies and single gene Mendelian disorders. Copyright © 2008 John Wiley & Sons, Ltd. [source] Kidney Injury Molecule-1 is an Early Noninvasive Indicator for Donor Brain Death-Induced Injury Prior to Kidney TransplantationAMERICAN JOURNAL OF TRANSPLANTATION, Issue 8 2009W. N. Nijboer With more marginal deceased donors affecting graft viability, there is a need for specific parameters to assess kidney graft quality at the time of organ procurement in the deceased donor. Recently, kidney injury molecule-1 (Kim-1) was described as an early biomarker of renal proximal tubular damage. We assessed Kim-1 in a small animal brain death model as an early and noninvasive marker for donor-derived injury related to brain death and its sequelae, with subsequent confirmation in human donors. In rat kidney, real-time PCR revealed a 46-fold Kim-1 gene upregulation after 4 h of brain death. In situ hybridization showed proximal tubular Kim-1 localization, which was confirmed by immunohistochemistry. Also, Luminex assay showed a 6.6-fold Kim-1 rise in urine after 4 h of brain death. In human donors, 2.5-fold kidney injury molecule-1 (KIM-1) gene upregulation and 2-fold higher urine levels were found in donation after brain death (DBD) donors compared to living kidney donors. Multiple regression analysis showed that urinary KIM-1 at brain death diagnosis was a positive predictor of recipient serum creatinine, 14 days (p < 0.001) and 1 year (p < 0.05) after kidney transplantation. In conclusion, we think that Kim-1 is a promising novel marker for the early, organ specific and noninvasive detection of brain death-induced donor kidney damage. [source] | |||||||||||||