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981.
Conventional wound therapy utilizes wound coverage to prevent infection, trauma, and fluid and thermal loss. However, this approach is often inadequate for large and/or chronic wounds, which require active intervention via therapeutic cells to promote healing. To address this need, a patch which delivers multipotent adult progenitor cells (MAPCs) is developed. Medical‐grade polyurethane (PU) films are modified using plasma immersion ion implantation (PIII), which creates a radical‐rich layer capable of rapidly and covalently attaching biomolecules. It is demonstrated that a short treatment duration of 400 s maximizes surface activation and wettability, minimizes reduction in gas permeability, and preserves the hydrolytic resistance of the PU film. The reactivity of PIII‐treated PU is utilized to immobilize the extracellular matrix protein tropoelastin in a functional conformation that stably withstands medical‐grade ethylene oxide sterilization. The PIII‐treated tropoelastin‐functionalized patch significantly promotes MAPC adhesion and proliferation over standard PU, while fully maintaining cell phenotype. Topical application of the MAPC‐seeded patch transfers cells to a human skin model, while undelivered MAPCs repopulate the patch surface for subsequent cell transfer. The potential of this new wound patch as a reservoir for the sustained delivery of therapeutic MAPCs and cell‐secreted factors for large and/or non‐healing wounds is indicated in the findings.  相似文献   
982.
User-friendly, low-cost equipment for preventive screening of severe or deadly pathologies are one of the most sought devices by the National Health Services, as they allow early disease detection and treatment, often avoiding its degeneration. In recent years more and more research groups are developing devices aimed at these goals employing gas sensors. Here, nanostructured chemoresistive metal oxide (MOX) sensors were employed in a patented prototype aimed to detect volatile organic compounds (VOCs), exhaled by blood samples collected from patients affected by colorectal cancer and from healthy subjects as a control. Four sensors, carefully selected after many years of laboratory tests on biological samples (cultured cells, human stools, human biopsies, etc.), were based here on various percentages of tin, tungsten, titanium, niobium, tantalum and vanadium oxides. Sensor voltage responses were statistically analyzed also with the receiver operating characteristic (ROC) curves, that allowed the identification of the cut-off discriminating between healthy and tumor affected subjects for each sensor, leading to an estimate of sensitivity and specificity parameters. ROC analysis demonstrated that sensors employing tin and titanium oxides decorated with gold nanoparticles gave sensitivities up to 80% yet with a specificity of 70%.  相似文献   
983.
The human proteome is composed of a diverse and heterogeneous range of gene products/proteoforms/protein species. Because of the growing amount of information about proteoforms generated by different methods, we need a convenient approach to make an inventory of the data. Here, we present a database of proteoforms that is based on information obtained by separation of proteoforms using 2DE followed by shotgun ESI–LC–MS/MS. The database's principles and structure are described. The database is called “2DE-pattern” as it contains multiple isoform-centric patterns of proteoforms separated according to 2DE principles. The database can be freely used at http://2de-pattern.pnpi.nrcki.ru .  相似文献   
984.
985.
Journal of Solid State Electrochemistry - A simple and green approach for creating a highly capacitive molybdenum disulphide (MoS2) anode material for lithium-ion batteries is proposed. The...  相似文献   
986.
987.
Accreditation and Quality Assurance - During the 2011 to 2018 food microbiology proficiency testing (PT) schemes organized by REQUASUD, a systematic analytical issue was detected. For the...  相似文献   
988.
Journal of Sol-Gel Science and Technology - The Zn1.9Cu0.1SiO4 pigment was obtained by two variants of “soft” chemistry methods: using sol–gel synthesis in ethanol from TEOS and...  相似文献   
989.
Anti-mullerian hormone (AMH) is a cytokine of transforming growth factor β (TGF-β) superfamily able to induce apoptosis in cells bearing specific AMH type II receptors (AMHRII). AMHRII is overexpressed in some malignant cells, so at present recombinant AMH (rAMH) is considered as a new candidate antineoplastic drug. The use of rAMH may be especially effective in case of such severe diseases as ovarian, prostate and breast cancer. However, the development of a new drug is hampered by the laboriousness of obtaining highly purified rAMH and by the lack of data about the pharmacological characteristics of rAMH derivatives. In this work, we obtained preparations of prohormone, half-cleaved rAMH and a C-terminal fragment of rAMH, which was confirmed by qualitative and quantitative analyses. To obtain rAMH and its derivatives we used a previously developed highly effective producer strain containing the optimized human AMH gene. The production process has been divided into several stages: (a) rAMH biosynthesis in the bioreactor; (b) culture media preparation; (c) purification of rAMH and its derivatives using immunoaffinity chromatography and reversed-phase HPLC; (d) identification of the purified proteins by immunoblotting and analytical reversed-phase HPLC; and (e) evaluation of the hormone forms activity. The obtained proteins may be used in preclinical trials and in vitro study of rAMH derivatives properties.  相似文献   
990.

We introduce energy-preserving integrators for nonholonomic mechanical systems. We will see that the nonholonomic dynamics is completely determined by a triple \(({{\mathcal {D}}}^*, \varPi , \mathcal {H})\), where \({{\mathcal {D}}}^*\) is the dual of the vector bundle determined by the nonholonomic constraints, \(\varPi \) is an almost-Poisson bracket (the nonholonomic bracket) and \( \mathcal {H}: {{\mathcal {D}}}^*\rightarrow \mathbb {R}\) is a Hamiltonian function. For this triple, we can apply energy-preserving integrators, in particular, we show that discrete gradients can be used in the numerical integration of nonholonomic dynamics. By construction, we achieve preservation of the constraints and of the energy of the nonholonomic system. Moreover, to facilitate their applicability to complex systems which cannot be easily transformed into the aforementioned almost-Poisson form, we rewrite our integrators using just the initial information of the nonholonomic system. The derived procedures are tested on several examples: a chaotic quartic nonholonomic mechanical system, the Chaplygin sleigh system, the Suslov problem and a continuous gearbox driven by an asymmetric pendulum. Their performance is compared with other standard methods in nonholonomic dynamics, and their merits verified in practice.

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