18 research outputs found

    Некоторые особенности структурной динамики межсекторальных ресурсных потоков в научной системе Украины

    Get PDF
    Представлен анализ динамики финансирования научно-технической деятельности в аспекте основных источников средств и исполнителей за весь период независимости Украины. Изложен авторский подход к оцениванию роли государства и других экономических субъектов, который адаптирует требования международных учетных стандартов к реалиям отечественной экономики.Представлено аналіз динаміки фінансування науково-технічної діяльності в аспекті головних джерел коштів та виконавців за весь період незалежності України. Викладено авторський підхід до оцінювання ролі держави та інших економічних суб’єктів, що адаптує вимоги міжнародних облікових стандартів до реалій вітчизняної економіки.An analysis of the R&D funding dynamics in terms of main funding sources and performers over the period of the Ukrainian independence is given. The author’s approach to evaluating the role of the government and other economic entities, which adapts the requirements of international accounting standards to the realities of the national economy, is shown

    Photocytotoxicity of mTHPC (Temoporfin) Loaded Polymeric Micelles Mediated by Lipase Catalyzed Degradation

    Get PDF
    Purpose. To study the in vitro photocytotoxicity and cellular uptake of biodegradable polymeric micelles loaded with the photosensitizer mTHPC, including the effect of lipase-catalyzed micelle degradation. Methods. Micelles of mPEG750-b-oligo(ɛ-caprolactone)5 (mPEG750-b-OCL5) with a hydroxyl (OH), benzoyl (Bz) or naphthoyl (Np) end group were formed and loaded with mTHPC by the film hydration method. The cellular uptake of the loaded micelles, and their photocytotoxicity on human neck squamous carcinoma cells in the absence and presence of lipase were compared with free and liposomal mTHPC (Fospeg ®). Results. Micelles composed of mPEG750-b-OCL5 with benzoyl and naphtoyl end groups had the highest loading capacity up to 30 % (w/w), likely due to π–π interactions between the aromatic end group and the photosensitizer. MTHPC-loaded benzoylated micelles (0.5 mg/mL polymer) did not display photocytotoxicity or any mTHPC-uptake by the cells, in contrast to free and liposomal mTHPC. After dilution of the micelles below the critical aggregation concentration (CAC), or after micelle degradation by lipase, photocytotoxicity and cellular uptake of mTHPC were restored. Conclusion. The high loading capacity of the micelles, the high stability of mTHPC-loaded micelles above the CAC, and the lipase-induced release of the photosensitizer makes these micelles very promising carriers for photodynamic therapy in vivo. KEY WORDS: drug release; enzymatic degradation; meta-tetra(hydroxyphenyl)chlorin (mTHPC); photodynamic therapy (PDT); polymeric micelles

    Genomic analyses identify hundreds of variants associated with age at menarche and support a role for puberty timing in cancer risk

    Get PDF
    The timing of puberty is a highly polygenic childhood trait that is epidemiologically associated with various adult diseases. Using 1000 Genomes Project-imputed genotype data in up to similar to 370,000 women, we identify 389 independent signals (P <5 x 10(-8)) for age at menarche, a milestone in female pubertal development. In Icelandic data, these signals explain similar to 7.4% of the population variance in age at menarche, corresponding to similar to 25% of the estimated heritability. We implicate similar to 250 genes via coding variation or associated expression, demonstrating significant enrichment in neural tissues. Rare variants near the imprinted genes MKRN3 and DLK1 were identified, exhibiting large effects when paternally inherited. Mendelian randomization analyses suggest causal inverse associations, independent of body mass index (BMI), between puberty timing and risks for breast and endometrial cancers in women and prostate cancer in men. In aggregate, our findings highlight the complexity of the genetic regulation of puberty timing and support causal links with cancer susceptibility

    Genomic analyses identify hundreds of variants associated with age at menarche and support a role for puberty timing in cancer risk

    Get PDF
    The timing of puberty is a highly polygenic childhood trait that is epidemiologically associated with various adult diseases. Using 1000 Genomes Project–imputed genotype data in up to ~370,000 women, we identify 389 independent signals (P < 5 × 108^{−8}) for age at menarche, a milestone in female pubertal development. In Icelandic data, these signals explain ~7.4% of the population variance in age at menarche, corresponding to ~25% of the estimated heritability. We implicate ~250 genes via coding variation or associated expression, demonstrating significant enrichment in neural tissues. Rare variants near the imprinted genes MKRN3 and DLK1 were identified, exhibiting large effects when paternally inherited. Mendelian randomization analyses suggest causal inverse associations, independent of body mass index (BMI), between puberty timing and risks for breast and endometrial cancers in women and prostate cancer in men. In aggregate, our findings highlight the complexity of the genetic regulation of puberty timing and support causal links with cancer susceptibility

    Membrane activity of the phospholipase C-δ(1) pleckstrin homology (PH) domain

    No full text
    PH-PLCδ(1) [the PH domain (pleckstrin homology domain) of PLCδ(1) (phospholipase C-δ(1))] is among the best-characterized phosphoinositide-binding domains. PH-PLCδ(1) binds with high specificity to the headgroup of PtdIns(4,5)P(2), but little is known about its interfacial properties. In the present study, we show that PH-PLCδ(1) is also membrane-active and can insert significantly into PtdIns(4,5)P(2)-containing monolayers at physiological (bilayer-equivalent) surface pressures. However, this membrane activity appears to involve interactions distinct from those that target PH-PLCδ(1) to the PtdIns(4,5)P(2) headgroup. Whereas the majority of PtdIns(4,5)P(2)-bound PH-PLCδ(1) can be displaced by adding excess of soluble headgroup [Ins(1,4,5)P(3)], membrane activity of PH-PLCδ(1) cannot. PH-PLCδ(1) differs from other phosphoinositide-binding domains in that its membrane insertion does not require that the phosphoinositide-binding site be occupied. Significant monolayer insertion remains when the phosphoinositide-binding site is mutated, and PH-PLCδ(1) can insert into monolayers that contain no PtdIns(4,5)P(2) at all. Our results suggest a model in which reversible membrane binding of PH-PLCδ(1), mediated by PtdIns(4,5)P(2) or other acidic phospholipids, occurs without membrane insertion. Accumulation of the PH domain at the membrane surface enhances the efficiency of insertion, but does not significantly affect its extent, whereas the presence of phosphatidylethanolamine and cholesterol in the lipid mixture promotes the extent of insertion. This is the first report of membrane activity in an isolated PH domain and has implications for understanding the membrane targeting by this common type of domain

    Angiogenic endothelium shows lactadherin-dependent phagocytosis of aged erythrocytes and apoptotic cells

    No full text
    Angiogenic endothelium plays a crucial role in tumor growth. During angiogenesis, complex alterations in the microenvironment occur. In response, the endothelium undergoes phenotypic changes, for example overexpression of alpha(v)-integrins. Here, we show that the overexpression of alpha(v)-integrins on angiogenic endothelial cells is engaged in phagocytic actions involving binding ("tethering") and uptake ("tickling") of lactadherin (also termed MFG-E8)-opsonized particles. Phosphatidylserine (PS)-exposing multilamellar vesicles, "aged" erythrocytes, and apoptotic melanoma cells incubated with lactadherin were all phagocytosed by angiogenic endothelial cells in vitro. Furthermore, we demonstrated lactadherin expression in and around tumor blood vessels making opsonization in situ plausible. By engineering the surface of erythrocytes with covalently coupled cyclic Arg-Gly-Asp (RGD) peptides-mimicking lactadherin opsonization-we could induce phagocytosis by angiogenic endothelial cells both in vitro and in vivo. In vitro, this was confirmed by cytochalasin D preincubation. When RGD-erythrocytes were administered intravenously in tumor-bearing mice, blood vessel congestion followed by tumor core necrosis was seen. Moreover, RGD-erythrocytes could delay tumor growth in a murine melanoma model, possibly through induction of tumor infarctions. These results reveal that angiogenic endothelial cells have phagocytic properties for lactadherin-opsonized large particles and apoptotic cells. Implications of our findings for diagnostic and therapy of angiogenesis-driven diseases are discussed

    The assessment of Pseudomonas aeruginosa lectin LecA binding characteristics of divalent galactosides using multiple techniques

    Get PDF
    Pseudomonas aeruginosa is a widespread opportunistic pathogen that is capable of colonizing various human tissues and is resistant to many antibiotics. LecA is a galactose binding tetrameric lectin involved in adhesion, infection and biofilm formation. This study reports on the binding characteristics of mono- and divalent (chelating) ligands to LecA using different techniques. These techniques include Affinity Capillary Electrophoresis (ACE), Bio Layer Interferometry (BLI), Native Mass Spectrometry and a Thermal Shift Assay. Aspects of focus include: affinity, selectivity, binding kinetics and residence time. The affinity of a divalent ligand was determined to be in the low nanomolar range for all of the used techniques and with a ligand residence time of approximately 7 hours, while no strong binding was seen to related lectin tetramers. Each of the used techniques provides a unique and complementary insight into the chelation based binding mode of the divalent ligand to the LecA tetramer
    corecore