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51.
Calcified pseudoneoplasms of the neuraxis (CAPNON) are a rare diagnostic entity. They have been reported intra‐cranially as well as in the spine, and are most commonly found at the skull base. This is a case report of a 38‐year‐old woman who presented with bilateral CAPNON, diagnosed 8 years apart. While there are approximately 46 reported in the current literature of cerebral and spinal fibro‐osseous lesions, this is the first report of separate lesions. 相似文献
52.
Min Xie Farhad Vesuna Mahendran Botlagunta Guus Martinus Bol Ashley Irving Yehudit Bergman Ramachandra S. Hosmane Yoshinori Kato Paul T. Winnard Jr Venu Raman 《Oncotarget》2015,6(30):29901-29913
DDX3X (DDX3), a human RNA helicase, is over expressed in multiple breast cancer cell lines and its expression levels are directly correlated to cellular aggressiveness. NZ51, a ring-expanded nucleoside analogue (REN) has been reported to inhibit the ATP dependent helicase activity of DDX3. Molecular modeling of NZ51 binding to DDX3 indicated that the 5:7-fused imidazodiazepine ring of NZ51 was incorporated into the ATP binding pocket of DDX3. In this study, we investigated the anticancer properties of NZ51 in MCF-7 and MDA-MB-231 breast cancer cell lines. NZ51 treatment decreased cellular motility and cell viability of MCF-7 and MDA-MB-231 cells with IC50 values in the low micromolar range. Biological knockdown of DDX3 in MCF-7 and MDA-MB-231 cells resulted in decreased proliferation rates and reduced clonogenicity. In addition, NZ51 was effective in killing breast cancer cells under hypoxic conditions with the same potency as observed during normoxia. Mechanistic studies indicated that NZ51 did not cause DDX3 degradation, but greatly diminished its functionality. Moreover, in vivo experiments demonstrated that DDX3 knockdown by shRNA resulted in reduced tumor volume and metastasis without altering tumor vascular volume or permeability-surface area. In initial in vivo experiments, NZ51 treatment did not significantly reduce tumor volume. Further studies are needed to optimize drug formulation, dose and delivery. Continuing work will determine the in vitro-in vivo correlation of NZ51 activity and its utility in a clinical setting. 相似文献
53.
Haka AS Shafer-Peltier KE Fitzmaurice M Crowe J Dasari RR Feld MS 《Proceedings of the National Academy of Sciences of the United States of America》2005,102(35):12371-12376
We employ Raman spectroscopy to diagnose benign and malignant lesions in human breast tissue based on chemical composition. In this study, 130 Raman spectra are acquired from ex vivo samples of human breast tissue (normal, fibrocystic change, fibroadenoma, and infiltrating carcinoma) from 58 patients. Data are fit by using a linear combination model in which nine basis spectra represent the morphologic and chemical features of breast tissue. The resulting fit coefficients provide insight into the chemical/morphological makeup of the tissue and are used to develop diagnostic algorithms. The fit coefficients for fat and collagen are the key parameters in the resulting diagnostic algorithm, which classifies samples according to their specific pathological diagnoses, attaining 94% sensitivity and 96% specificity for distinguishing cancerous tissues from normal and benign tissues. The excellent results demonstrate that Raman spectroscopy has the potential to be applied in vivo to accurately classify breast lesions, thereby reducing the number of excisional breast biopsies that are performed. 相似文献
54.
Ramesh K Sood Vishweshwar S Bhadti Ali I Fattom Robert B Naso Brent E Korba Earl R Kern Huan-Ming Chen Ramachandra S Hosmane 《Antiviral research》2002,53(2):159-164
Novel ring-expanded nucleoside (REN) analogs (1-3) containing 5:7 fused ring systems as the heterocyclic base were found to be potent and selective inhibitors of hepatitis B virus (HBV) replication in cultured human hepatoblastoma 2.2.15 cells. The most active compound, 6-amino-4,5-dihydro-8H-1-(beta-D-ribofuranosyl)imidazo[4,5-e][1,3]diazepine-4,8-dione (1), inhibited the synthesis of intracellular HBV replication intermediates and extracellular virion release in 2.2.15 cells with 50% effective concentration (EC50) of 0.604 and 0.131 microM, respectively. All three compounds had no effect on the synthesis of viral ribonucleic acids (RNA) in 2.2.15 cells. These compounds also exhibited low cellular toxicity in stationary and rapidly growing cell systems. 相似文献
55.
Fluorescence tomographic imaging in turbid media using early-arriving photons and Laplace transforms
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Jun Wu Lev Perelman Ramachandra R. Dasari Michael S. Feld 《Proceedings of the National Academy of Sciences of the United States of America》1997,94(16):8783-8788
We present a multichannel tomographic technique to detect fluorescent objects embedded in thick (6.4 cm) tissue-like turbid media using early-arriving photons. The experiments use picosecond laser pulses and a streak camera with single photon counting capability to provide short time resolution and high signal-to-noise ratio. The tomographic algorithm is based on the Laplace transform of an analytical diffusion approximation of the photon migration process and provides excellent agreement between the actual positions of the fluorescent objects and the experimental estimates. Submillimeter localization accuracy and 4- to 5-mm resolution are demonstrated. Moreover, objects can be accurately localized when fluorescence background is present. The results show the feasibility of using early-arriving photons to image fluorescent objects embedded in a turbid medium and its potential in clinical applications such as breast tumor detection. 相似文献
56.
V. Phaniendra Kumar S. Ramachandra Reddy M. H. Das 《Indian journal of otolaryngology and head and neck surgery》1997,49(3):262-264
The state of art of Laryngoplastic surgery gaining day to day importance where Rhinoplasty stood almost a century ago. Medialization
Laryngoplasty using Silastic Implant for the correction of symptomatic unilateral vocal cord paralysis is discussed. 相似文献
57.
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59.
E S Raveché J Phillips F Mahboudi A Dang H Fernandes S Ramachandra T Lin B Peng 《International Journal of Clinical & Laboratory Research》1992,22(4):220-234
B-1 (CD5+ B) cells appear early in ontogeny, produce mainly unmutated polyreactive antibodies, and are capable of self-renewal. B-1 cells clonally expand with age and are the malignant cell in chronic lymphocytic leukemia. In this report immunological analysis of B-1 malignancies in NZB mice, a murine model of chronic lymphocytic leukemia, is related to current information on B-1 cells. B-1 clones from NZB mice produce high levels of interleukin-10, detected at the RNA level by semi-quantitative polymerase chain reaction. In addition, the B-1 malignant clones in NZB mice and their hybrids, are negative for B220/6B2 expression, the B-specific antigenic form of CD45 which is a membrane-associated phosphatase involved in lymphocyte activation. Both the autocrine production by B-1 cells of interleukin-10 and altered CD45 expression may be responsible for the clonal expansion of these cells, as well as the accompanying T cell expansion. We report the establishment of an in vitro cytotoxic CD8+ T cell line derived from an NZB with a B-1 malignancy. The effect of B-1 cell-derived interleukin-10 on subsets of T lymphocytes may account for the immunoregulatory properties of B-1 cells. In addition, the NZB malignancies were also characterized for immunoglobulin variable region sequence and antigen specificity. The B-1 malignancies produced immunoglobulin derived from unmutated germline sequences with no N base substitutions. It appears that both the immunoglobulin and interleukin-10 produced by the B-1 malignant cell in NZB mice may have immunoregulatory properties. A study of B-1 malignancies may shed light on the immunoregulatory properties of non-clonally expanded normal B-1 cells. 相似文献
60.
Synthesis of novel caffeic acid esters (1 and 2) was accomplished starting from appropriately substituted benzaldehydes (3 and 9). While compound 2 exhibited potent anti-oxidative activity in both the nitroblue tetrazolium and 1,1-diphenyl-2-picrylhydrazyl radical-scavenging models, compound 1 showed moderate 5-lipoxygenase inhibitory activity. 相似文献