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Advaita Ganguly Ravindra B. MalabadiRaimer Loebenberg Mavanur R. SureshHoon H. Sunwoo 《Diagnostic microbiology and infectious disease》2014
Dengue and the more severe dengue hemorrhagic fever have been a very critical public health problem globally. Millions of people especially in the tropical areas get infected with dengue. An efficient diagnostic is very important for early screening of dengue infection. In dengue-infected patients, the nonstructural protein NS1 is present on the surface of infected cells and secreted in plasma. The NS1 antigen is an important target for developing a quick diagnostic largely due to its long presence in the blood. We have developed a simple-to-use immunoswab-based diagnostic procedure employing monoclonal antibodies and the second-generation quadromas. The detection limit for NS1 has been established to be in the subnanogram range. The assay is very sensitive, has a visual end point, and also being extremely inexpensive. With this assay, screening time for a dengue-infected person would be very rapid. 相似文献
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Stratification of the aggressiveness of prostate cancer using pre‐biopsy multiparametric MRI (mpMRI)
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Durgesh Kumar Dwivedi Rajeev Kumar Girdhar S. Bora Sanjay Thulkar Sanjay Sharma Siddhartha Datta Gupta Naranamangalam R. Jagannathan 《NMR in biomedicine》2016,29(3):232-238
Risk stratification, based on the Gleason score (GS) of a prostate biopsy, is an important decision‐making tool in prostate cancer management. As low‐grade disease may not need active intervention, the ability to identify aggressive cancers on imaging could limit the need for prostate biopsies. We assessed the ability of multiparametric MRI (mpMRI) in pre‐biopsy risk stratification of men with prostate cancer. One hundred and twenty men suspected to have prostate cancer underwent mpMRI (diffusion MRI and MR spectroscopic imaging) prior to biopsy. Twenty‐six had cancer and were stratified into three groups based on GS: low grade (GS ≤ 6), intermediate grade (GS = 7) and high grade (GS ≥ 8). A total of 910 regions of interest (ROIs) from the peripheral zone (PZ, range 25–45) were analyzed from these 26 patients. The metabolite ratio [citrate/(choline + creatine)] and apparent diffusion coefficient (ADC) of voxels were calculated for the PZ regions corresponding to the biopsy cores and compared with histology. The median metabolite ratios for low‐grade, intermediate‐grade and high‐grade cancer were 0.29 (range: 0.16, 0.61), 0.17 (range: 0.13, 0.32) and 0.13 (range: 0.05, 0.23), respectively (p = 0.004). The corresponding mean ADCs (×10–3 mm2/s) for low‐grade, intermediate‐grade and high‐grade cancer were 0.99 ± 0.08, 0.86 ± 0.11 and 0.69 ± 0.12, respectively (p < 0.0001). The combined ADC and metabolite ratio model showed strong discriminatory ability to differentiate subjects with GS ≤ 6 from subjects with GS ≥ 7 with an area under the curve of 94%. These data indicate that pre‐biopsy mpMRI may stratify PCa aggressiveness noninvasively. As the recent literature data suggest that men with GS ≤ 6 cancer may not need radical therapy, our data may help limit the need for biopsy and allow informed decision making for clinical intervention. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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Motaz M. Alyafi Abdulhadi A. AlAmodi Bernhard H. J. Juurlink Paul Ganguly 《The International journal of angiology》2012,21(2):77-80
There is a debate among medical education experts on the application of dissection or prosection for learning anatomy. However, the literature reveals that the majority of published articles are in favor of dissection. In this article, we present a case of an abdominal aortic aneurysm (AAA) with intracardiac thrombus in a cadaver on routine dissection. We will discuss possible explanations for such finding and provide some insight into how this finding can support the significance of the cadaver-based teaching of anatomy of the medical students. Initially, the abdomen was dissected and exposed to study the abdominal structures in an anatomy class and later the thoracic region was dissected and all the clinical abnormalities were examined and documented. Autopsy of the clot was obtained for histopathology analysis. The intracardiac thrombus was present in the right atrium characterized by its projection into the superior vena cava, inferior vena cava, and the right ventricle. The AAA was extensive and inferior to the renal arteries constricting the entire inferior vena cava. Moreover, associated findings included presence of numerous collaterals in the thoracic region near the superior vena cava; histological examination of the clot showed extensive population of leukocytes. There were enlarged mediastinal lymph nodes. Our cadaver showed an excellent model for integrating between clinical anatomy and pathology by triggering medical students to think of normal and abnormal structures: often called “thinking outside the box.” Such an effort might help them in developing their thought processes and future medical careers. 相似文献
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Male breast cancer (MBC) is an uncommon and poorly understood disease. Recent molecular studies have shown important differences from female breast cancer which are likely to influence treatment strategies from the current female‐based management towards a more tailored approach. Significantly more MBCs than female breast cancers arise with an underlying germline cancer predisposition, and display a vastly different penetrance compared with females. Furthermore, the genophenotypical association of basal‐like cancer with BRCA1 present in female breast cancer is not observed in male breast cancer. Differences in somatic changes between male and female breast cancer have also been reported, with particular enrichment of PIK3CA mutations and a paucity of TP53 mutations. In general, chromosomal‐based changes, in particular regions of gains, are seen more frequently in male than female breast cancer and methylation is seen less frequently. Clinically, several molecular subtypes with prognostic relevance have been described, including chromosomal complex high and methylation high groups, and subgroups with profiling signatures pertaining to epithelial mesenchymal transition and hormonal therapy insensitivity. As with female breast cancer, attention to male specific multicentre trials based on the individual characteristics are needed, together with establishment of reliable preclinical models to understand more clearly the pathogenesis of male breast cancer and improve the general poor outcome of this disease. 相似文献
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Maria Fatima Falangola Xingju Nie Ralph Ward Emilie T. McKinnon Siddhartha Dhiman Paul J. Nietert Joseph A. Helpern Jens H. Jensen 《NMR in biomedicine》2020,33(9)
The 3×Tg‐AD mouse is one of the most studied animal models of Alzheimer's disease (AD), and develops both amyloid beta deposits and neurofibrillary tangles in a temporal and spatial pattern that is similar to human AD pathology. Additionally, abnormal myelination patterns with changes in oligodendrocyte and myelin marker expression are reported to be an early pathological feature in this model. Only few diffusion MRI (dMRI) studies have investigated white matter abnormalities in 3×Tg‐AD mice, with inconsistent results. Thus, the goal of this study was to investigate the sensitivity of dMRI to capture brain microstructural alterations in 2‐month‐old 3×Tg‐AD mice. In the fimbria, the fractional anisotropy (FA), kurtosis fractional anisotropy (KFA), and radial kurtosis (K┴) were found to be significantly lower in 3×Tg‐AD mice than in controls, while the mean diffusivity (MD) and radial diffusivity (D┴) were found to be elevated. In the fornix, K┴ was lower for 3×Tg‐AD mice; in the dorsal hippocampus MD and D┴ were elevated, as were FA, MD, and D┴ in the ventral hippocampus. These results indicate, for the first time, dMRI changes associated with myelin abnormalities in young 3×Tg‐AD mice, before they develop AD pathology. Morphological quantification of myelin basic protein immunoreactivity in the fimbria was significantly lower in the 3×Tg‐AD mice compared with the age‐matched controls. Our results demonstrate that dMRI is able to detect widespread, significant early brain morphological abnormalities in 2‐month‐old 3×Tg‐AD mice. 相似文献
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Govind K Makharia Chris J J Mulder Khean Lee Goh Vineet Ahuja Julio C Bai Carlo Catassi Peter H R Green Siddhartha Datta Gupta Knut E A Lundin Balakrishnan Siddartha Ramakrishna Ramakant Rawat Hanish Sharma Ajit Sood Chikako Watanabe Peter R Gibson World Gastroenterology Organization‐Asia Pacific Association of Gastroenterology Working Party on Celiac Disease 《Journal of gastroenterology and hepatology》2014,29(4):666-677