609 research outputs found
Finite range Decomposition of Gaussian Processes
Let \D be the finite difference Laplacian associated to the lattice
\bZ^{d}. For dimension , and a sufficiently large
positive dyadic integer, we prove that the integral kernel of the resolvent
G^{a}:=(a-\D)^{-1} can be decomposed as an infinite sum of positive
semi-definite functions of finite range, for
. Equivalently, the Gaussian process on the lattice with
covariance admits a decomposition into independent Gaussian processes
with finite range covariances. For , has a limiting scaling form
as .
As a corollary, such decompositions also exist for fractional powers
(-\D)^{-\alpha/2}, . The results of this paper give an
alternative to the block spin renormalization group on the lattice.Comment: 26 pages, LaTeX, paper in honour of G.Jona-Lasinio.Typos corrected,
corrections in section 5 and appendix
Thromboembolic events in patients treated with anti-angiogenic drugs
Induction of neo-angiogenesis is a fundamental step in many pathological conditions. The therapeutic value of inhibiting angiogenesis is an interesting area of research in oncology, with vascular endothelial growth factor (VEGF) being the most suitable anti-angiogenic target. In the last decade a number of anti-VEGF drugs have demonstrated, especially in combination with standard chemotherapy, clinical efficacy in the treatment of different solid tumor types. As data from clinical trials on anti-VEGF drugs are becoming available, it is increasingly recognized that VEGF, in addition to being a permeability, proliferation, and migration factor, is also a maintenance and protection factor for endothelial cells, being capable of regulating multiple biological functions, i.e. the production of vasoactive mediators and the expression of components of the thrombolytic and coagulation pathways. Consequently, the disturbance of vascular homeostasis by blocking VEGF may lead to endothelial dysfunction and adverse vascular effects, such as venous and arterial thromboembolic events. In preclinical models angiogenesis and the increased expression of VEGF has been associated to altered expression of proinflammatory genes. These genes may be regulated in a biphasic manner, and it is possible that anti-VEGF therapy may disrupt a negative feedback loop that leads to potential in situ thrombus formation. Accordingly, combination treatment with bevacizumab and chemotherapy, compared with chemotherapy alone, was recently associated with an increased risk of thromboembolism. The present review considers the biological mechanisms and clinical impact of thromboembolic complications during anti-angiogenic treatments in cancer patients
Non-steroidal anti-inflammatory drugs in cancer prevention and therapy
Long-term use of non-steroidal anti-inflammatory drugs (NSAIDs) can be regarded as an effective approach for cancer chemoprevention, as demonstrated by a bulk of clinical and experimental evidence. However, the clinical use of these drugs as chemopreventive agents is limited by many open questions about the optimal drug, dose, duration of therapy and knowledge about the mechanism(s) by which these drugs act. In particular, the recent data on cardiovascular toxicity of coxibs has posed some limitations on the use of NSAIDs for cancer chemoprevention in the general population. The situation is different in certain genetically susceptible subgroups, such as in individuals with genetic mutations associated with hereditary nonpolyposis colon cancer (HNPCC) or familiar adenomatous polyps (FAP) in whom lifetime risk increases up to 70-90% and in whom the benefit of a chemopreventive drug might justify its use even in the presence of adverse effects
Interleukin-2 inhalation therapy in renal cell cancer: a case report and review of the literature
Renal cell carcinoma (RCC) is the most common malignancy of the kidney. One third of RCC presents metastatic disease at the time of diagnosis, usually leading to a fatal outcome. Small response rates were seen with most cytotoxic agents including gemcitabine and vinorelbine, whereas systemic therapy with high doses of interleukin 2 (IL-2) has been shown to provide durable complete remissions. However, in consideration of its severe toxicity, IL-2 immunotherapy is restricted to selected patients. Aerosol IL-2 has been introduced as an alternative therapy in cancer patients. However, only very few data are available on its use in patients with pulmonary metastatic RCC. This paper briefly summarizes current clinical experience with the use of inhaled IL-2 therapy, either as a single therapy or in combination with other treatments. In addition, we report on a male patient with pulmonary metastasized RCC who achieved a durable complete response to combined gemcitabine/vinorelbine and interleukin-2 inhalation therapy
Non-steroidal anti-inflammatory drugs in cancer prevention and therapy
Long-term use of non-steroidal anti-inflammatory drugs (NSAIDs) can be regarded as an effective approach for cancer chemoprevention, as demonstrated by a bulk of clinical and experimental evidence. However, the clinical use of these drugs as chemopreventive agents is limited by many open questions about the optimal drug, dose, duration of therapy and knowledge about the mechanism(s) by which these drugs act. In particular, the recent data on cardiovascular toxicity of coxibs has posed some limitations on the use of NSAIDs for cancer chemoprevention in the general population. The situation is different in certain genetically susceptible subgroups, such as in individuals with genetic mutations associated with hereditary nonpolyposis colon cancer (HNPCC) or familiar adenomatous polyps (FAP) in whom lifetime risk increases up to 70-90% and in whom the benefit of a chemopreventive drug might justify its use even in the presence of adverse effects
Biological effects of a software-controlled voltage pulse generator (PhyBack PBK-2C) on the release of vascular endothelial growth factor (VEGF)
Electrical stimulation (ES) may induce vascular permeability and physiological angiogenesis. ES of rat muscles significantly increases the microvessel density and vascular endothelial growth factor (VEGF) protein levels. Thus, a pilot study was designed to analyze the effects of low-voltage electric impulses on VEGF levels in patients with dystrophic ulcers
Prognostic value of vascular endothelial growth factor tumor tissue content of colorectal cancer
A longitudinal study was designed to quantify tumor tissue content of vascular endothelial growth factor (VEGF) in patients with colorectal cancer (CRC) and to evaluate its prognostic value in respect to the relapse-free and overall survivals
Serum sE-selectin levels and carcinoembryonic antigen mRNA-expressing cells in peripheral blood as prognostic factors in colorectal cancer patients
This study analyzed the possible prognostic value of presurgical serum soluble (s)E-selectin levels and/or carcinoembryonic antigen (CEA) mRNA positivity in predicting the disease-free survival of colorectal cancer (CRC) patients
Prognostic value of carcinoembryonic antigen and vascular endothelial growth factor tumor tissue content in colorectal cancer
This study was designed to assess the prognostic significance of the combined measurement of vascular endothelial growth factor (VEGF) and carcinoembryonic antigen (CEA) tissue content with respect to relapse-free and overall survival of patients with colorectal cancer (CRC)
Prognostic significance of adiponectin levels in non-metastatic colorectal cancer
Circulating adiponectin levels are inversely correlated with the risk of colorectal cancer (CRC). This study was designed to evaluate the association between adiponectin levels and the clinicopathological variables of CRC and to analyze the possible prognostic value of adiponectin in predicting relapse-free survival
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