Search results for "Metas"
showing 10 items of 1693 documents
Dynamics of multilayer adsorption: a Monte Carlo simulation
1992
Abstract The growth of an adsorbed film at an initially empty surface which is exposed at time t = 0 to a gas is studied within the framework of a kinetic lattice gas model by Monte Carlo simulation. The model includes an attractive potential V ( z ) between adsorbed particles at distance z from the surface, V(z) = −A z 3 and a nearest-neighbor attractive interaction between the gas atoms. Several choices of the surface potential depth A , corresponding to different sequence of layering transitions, are considered. The Monte Carlo process assumes random evaporation/condensation events of gas atoms in adsorbed layers close to the surface, while surface diffusion is disregarded. For temperatu…
Thoracic dumbbell spinal metastasis secondary to neuroendocrine tumor of unknown origin: Case report and literature review
2022
Background: Dumbbell tumors are typically benign schwannomas, neurofibromas, and meningiomas and only rarely there are malignant variants of these lesions or other malignant histotypes. Here, a 34-year-old male presented with a thoracic spinal dumbbell metastatic neuroendocrine carcinoma of unknown primary origin. Case Description: A 34-year-old male presented with 2 months of thoracic pain and progressive mid thoracic sensory loss. A post contrast thoracic MRI showed a dumbbell tumor localized between the T7 and T9 levels with extension laterally into the T7-T8 and T8-T9 foramina. The patient underwent a laminectomy for tumor resection following which his pain and gait improved. Histopath…
The Elovl5 enzyme in breast cancer : regulation of cancer cell proliferation and metastasis
2021
Breast cancer is the most diagnosed cancer and the leading cause of cancer death in women. The 5-year relative survival rate is less than 30% for metastatic breast cancer and metastases account for more than 75% of breast cancer deaths. Fatty acid metabolism is altered in cancer and contributes to tumor progression and metastasis. Here, we were interested in Elongation of very long chain fatty acids protein 5 (Elovl5) which catalyzes the elongation of long-chain fatty acids. We observed that the tumors from patients with a breast cancer had a lower expression of Elovl5 than paired normal breast tissue. However, low expression of Elovl5 is associated with a worse prognosis in breast cancer p…
Type-II transmembrane prolyl dipeptidases and matrix metalloproteinases in membrane vesicles of active endothelial cells.
2006
Conclusions: Endothelia cells in sparse culture are migratory and increase the production of gelatinases of serine- and metallo-classes in membrane vesicles. Collectively, proteases associated with membrane vesicles degrade extracellular matrix components including type-I and type-IV collagens, laminin and fibronectin. Inhibitor studies suggest the existence of small gelatinases that were derived from these serine- and metallo-proteases. Thus, further studies are warranted to demonstrate the cooperative action of metallo- and serine proteases on cell surfaces and in extracellular vesicles during endothelial cell migration in 3D collagenous matrices, and potential proteolytic activation mech…
Molecular profile study of extracellular vesicles for the identification of useful small “hit” in cancer diagnosis
2021
Tumor-secreted extracellular vesicles (EVs) are the main mediators of cell-cell communication, permitting cells to exchange proteins, lipids, and metabolites in varying physiological and pathological conditions. They contain signature tumor-derived molecules that reflect the intracellular status of their cell of origin. Recent studies have shown that tumor cell-derived EVs can aid in cancer metastasis through the modulation of the tumor microenvironment, suppression of the immune system, pre-metastatic niche formation, and subsequent metastasis. EVs can easily be isolated from a variety of biological fluids, and their content makes them useful biomarkers for the diagnosis, prognosis, monito…
DECORIN EFFECTS ON PROTEOMIC PROFILING OF BREAST CANCER CELLS: AN UPDATED STUDY
2015
The malignant carcinomas are characterized by several capabilities acquired by the neoplastic cells, among which the ability to invade the extracellular matrix (ECM) and to establish a crosstalk with several ECM components. Under this respect, the extracellular microenvironment is an entity extraordinarily rich of information with opposite signals. Our group has long undertaken the study of the effects of ECM molecules on the behavior of cancer cells in vitro. Among the studied molecules, the decorin was found to exert a non-permissive effect on the growth and motility of the transfected tumor cells. The decorin, belongs to the family of small leucine-rich proteoglycans (SLRP) and is involv…
Tumor hypoxia and therapeutic resistance
2008
For many years, the identification of tumor hypoxia, its systematic characterization and the assessment of its clinical relevance were not possible due to the lack of methods suitable for the routine measurement of intratumoral oxygen tensions in patients. In the late 1980s, a novel and clinically applicable standardized procedure was established enabling the determination of tumor oxygenation in accessible primary tumors, local recurrences, and metastatic lesions in patients using a computerized polarographic needle electrode system (Vaupel et al. 1991; Hockel et al. 1991). Within a relatively short period of time, the significance of tumor oxygenation for therapy outcome became evident in…
Tumor Oxygenation and Its Relevance to Tumor Physiology and Treatment
2003
For many years, the identification of tumor hypoxia, its systematic characterization and the assessment of its clinical relevance were not possible due to lack of methods suitable for the routine measurement of intratumoral oxygen tensions in patients. In the late 1980s, a novel and clinically applicable standardized procedure was established enabling the determination of the tissue oxygenation status in primary tumors, local recurrences, and metastatic lesions in patients using a computerized polarographic needle electrode system. Within a relatively short period of time, the significance of tumor oxygenation for therapy outcome became evident in numerous experimental and clinical studies.
Formation of metastable structures by phase separation triggered by initial composition gradients in thin films.
2012
Phase separation kinetics of a binary (A,B) mixture contained in a thin film of thickness D induced by a quench from the one-phase region into the miscibility gap is studied by simulations using a Cahn-Hilliard-Cook model. The initial randomly mixed state (50% A, 50% B) contains a concentration gradient perpendicular to the film, while the surfaces of the film are "neutral" (no preference for either A or B). In thermal equilibrium, a pattern of large A-rich and B-rich domains must result, separated by domain walls oriented perpendicularly to the external surfaces of the thin film. However, it is shown that for many choices of D and the strength of the initial gradient Ψ(g), instead a very l…
A Maze of Solid Solutions of Pimobendan Enantiomers: An Extraordinary Case of Polymorph and Solvate Diversity
2017
Over 10 polymorphs and solvatomorphs of the chiral pharmaceutically active ingredient pimobendan were found to lack enantioselectivity in the solid state, accordingly, forming solid solutions of enantiomers, which is reported to be a rare phenomenon. Solid form screening was performed on different enantiomeric composition samples to analyze obtained phases with powder X-ray diffraction and thermogravimetric differential scanning calorimetry. For nonsolvated forms, a melt phase diagram has been constructed convincingly showing the existence of stable and metastable solid solutions near the pure enantiomer and around the racemic composition regions. A crystal structure study combined with sol…