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1.
Vascular endothelial growth factor (VEGF) and its receptors (VEGFRs) drive angiogenesis, and several VEGFR inhibitors are already approved for use as single agents or in combination with chemotherapy. Although there is a clear benefit with these drugs in a variety of tumors, the clinical response varies markedly among individuals. Therefore, there is a need for an efficient method to identify patients who are likely to respond to antiangiogenic therapy and to monitor its effects over time. We have recently developed a molecular imaging tracer for imaging VEGFRs known as scVEGF/99mTc; an engineered single-chain (sc) form of VEGF radiolabeled with technetium Tc 99m (99mTc). After intravenous injection, scVEGF/99mTc preferentially binds to and is internalized by VEGFRs expressed within tumor vasculature, providing information on prevalence of functionally active receptors. We now report that VEGFR imaging readily detects the effects of pazopanib, a small-molecule tyrosine kinase inhibitor under clinical development, which selectively targets VEGFR, PDGFR, and c-Kit in mice with HT29 tumor xenografts. Immunohistochemical analysis confirmed that the changes in VEGFR imaging reflect a dramatic pazopanib-induced decrease in the number of VEGFR-2+/CD31+ endothelial cells (ECs) within the tumor vasculature followed by a relative increase in the number of ECs at the tumor edges. We suggest that VEGFR imaging can be used for the identification of patients that are responding to VEGFR-targeted therapies and for guidance in rational design, dosing, and schedules for combination regimens of antiangiogenic treatment.  相似文献   
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Thiochrome caproate modified by the oxyethyl radical of the thiochrome derivative was studied for its effect on different indices of lipid metabolism in the liver and blood of albino rats. It was shown that when animals were fed on a standard laboratory diet, thiochrome caproate changed the amount of total and free fatty acids in the studied tissues and the fatty acid composition in the liver to a greater extent than thiochrome and hydroxythiamine.  相似文献   
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The apicoplast is a recently discovered, plastid-like organelle present in most apicomplexa. The methylerythritol phosphate (MEP) pathway involved in isoprenoid biosynthesis is one of the metabolic pathways associated with the apicoplast, and is a new promising therapeutic target in Plasmodium falciparum. Here, we check the presence of isoprenoid genes in four coccidian parasites according to genome database searches. Cryptosporidium parvum and C. hominis, which have no plastid genome, lack the MEP pathway. In contrast, gene expression studies suggest that this metabolic pathway is present in several development stages of Eimeria tenella and in tachyzoites of Toxoplasma gondii. We studied the potential of fosmidomycin, an antimalarial drug blocking the MEP pathway, to inhibit E. tenella and T. gondii growth in vitro. The drug was poorly effective even at high concentrations. Thus, both fosmidomycin sensitivity and isoprenoid metabolism differs substantially between apicomplexan species.  相似文献   
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BACKGROUND: Recent studies indicate that the innate component of immune defense plays an important role in the establishment of antigen-specific immune response. We have previously isolated a novel mouse gene tag7/PGRP that was shown to be involved in the innate component of the immune system, and its insect homologue is an upstream mediator of Toll signaling in Drosophila. METHODS: Transiently or stably genetically modified mouse tumor cell lines expressing Tag7 were used. Tumor growth rate and animal survival were analyzed. Possible effector cells involved in tumor suppression were detected immunohistochemically. RESULTS: Transfection of mammary gland adenocarcinoma cells with the tag7 cDNA did not alter their growth rate in vitro but diminished their tumorogenicity in vivo in syngeneic and immunodeficient animals. Increased incidence of apoptosis was registered in the modified tumors. Transient expression of Tag7 by mouse melanoma M3 cells elicited protective immunity against parental tumor cells. Immunohistochemical analysis revealed that tumors after immunization with the genetically modified cells were infiltrated with Mac1(+) cells, B220(+) cells, and NK cells. Using nude mice we observed rejection of modified cells, but did not detect memory formation. CONCLUSIONS: We can conclude that secretion of the Tag7 protein by genetically modified cells can induce mobilization of antigen-presenting cells and innate effectors. Memory mechanisms are mediated by T cell response. For the first time our results demonstrate that local secretion of Tag7-the molecule involved in innate immunity-may play an important role in the induction of effective antitumor response in mice.  相似文献   
6.
The role of NKT cells on antitumor activity of CpG oligodeoxynucleotides (ODNs) was evaluated by peritumoral injections of CpG-ODNs in s.c. melanoma-bearing mice of strains differing in the number of NKT cells (athymic nude mice, recombination-activating gene(-/-)/transgenic V(alpha)14/Vbeta8.2 mice that generate NKT cells; J(alpha)281(-/-) mice and CD1(-/-) mice, which both have a strongly reduced number of NKT cells; and C57BL/6 wild-type mice). Tumor growth was significantly inhibited in strains enriched or depleted of NKT cells. The two murine strains having a reduced number of NKT cells differed significantly in the CpG-dependent tumor growth inhibition: in J(alpha)281(-/-) mice this inhibition was superimposable to that observed in C57BL/6 mice, while in CD1(-/-) mice the inhibition was dramatic. The increased tumor inhibition in CD1(-/-) correlated with a significantly higher ratio of IFN-gamma-IL-4 production in response to CpG as compared with C57BL/6 and J(alpha)281(-/-) mice. Experiments in which preparations of APCs and lymphocytes of the three strains were mixed showed that in the presence of APCs not expressing CD1, the production of CpG-ODN-induced type 1 cytokines was higher. Phenotype analysis of IFN-gamma- and IL-4-producing cells revealed that the differences between CD1(-/-) and C57BL/6 in the production of these two cytokines were mainly due to CD3(+) T lymphocytes. These data point to a regulatory role for the CD1 molecule in antitumor activity induced by danger signals, independently of V(alpha)14 NKT cells. The identification of a CD1-dependent suppressive subpopulation(s) might have important implications for the study of tolerance in the context of cancer, autoimmunity, and transplantation.  相似文献   
7.
Kiselev SL  Larin SS  Gnuchev NV  Georgiev GP 《Genetika》2000,36(11):1431-1435
Modern gene therapeutic approaches towards the treatment of malignant neoplasms are discussed. Specifically, results of the first experiments on the development of vaccines on the basis of tumor cells modified with various cytokines and activation molecules are described. We compare effectiveness of different cytokines used for modification of tumor cells are made and consider possible mechanisms of vaccine action. The reasons for impossibility of the development of effective endogenous antitumor immunity are examined. The results of comparative analysis of the Tag7 protein antitumor activity are presented. This evidence clearly shows that Tag7 is a promising agent for anticancer therapy.  相似文献   
8.
There is some evidence for a role of music training in boosting phonological awareness, word segmentation, working memory, as well as reading abilities in children with typical development. Poor performance in tasks requiring temporal processing, rhythm perception and sensorimotor synchronization seems to be a crucial factor underlying dyslexia in children. Interestingly, children with dyslexia show deficits in temporal processing, both in language and in music. Within this framework, we test the hypothesis that music training, by improving temporal processing and rhythm abilities, improves phonological awareness and reading skills in children with dyslexia. The study is a prospective, multicenter, open randomized controlled trial, consisting of test, rehabilitation and re-test (ID NCT02316873). After rehabilitation, the music group (N = 24) performed better than the control group (N = 22) in tasks assessing rhythmic abilities, phonological awareness and reading skills. This is the first randomized control trial testing the effect of music training in enhancing phonological and reading abilities in children with dyslexia. The findings show that music training can modify reading and phonological abilities even when these skills are severely impaired. Through the enhancement of temporal processing and rhythmic skills, music might become an important tool in both remediation and early intervention programs.

Trial Registration

ClinicalTrials.gov NCT02316873  相似文献   
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In this work, the effect of Trametes pubescens laccase (TpL) used in combination with a low-molecular-weight ultra-filtered lignin (UFL) to improve mechanical properties of kraft liner pulp and chemi-thermo-mechanical pulp was studied. UFL was isolated by ultra-filtration from the kraft cooking black liquor obtained from softwood pulping. This by-product from the pulp industry contains an oligomeric lignin with almost twice the amount of free phenolic moieties than residual kraft pulp lignin. The reactivity of TpL on UFL and kraft pulp was studied by nuclear magnetic resonance spectroscopy and size exclusion chromatography. Laccase was shown to polymerise UFL and residual kraft pulp lignin in the fibres, seen by the increase in their average molecular weight and in the case of UFL as a decrease in the amount of phenolic hydroxyls. The laccase initiated cross-linking of lignin, mediated by UFL, which gives rise to more than a twofold increase in wet strength of kraft liner pulp handsheets without loosing other critical mechanical properties. Hence, this could be an interesting path to decrease mechano-sorptive creep that has been reported to lessen in extent as wet strength is given to papers. The laccase/2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) mediator system showed a greater increase in wet tensile strength of the resulting pulp sheets than the laccase/UFL system. However, other mechanical properties such as dry tensile strength, compression strength and Scott Bond internal strength were negatively affected by the laccase/ABTS system.  相似文献   
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