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141.
The method based on the ultra-performance liquid chromatography coupled with electrospray mass spectrometry (UPLC/ESI–MS) instrument was used for the identification and quantification of the most commercial Bovidae fibres (wool, cashmere and yak). In the present paper, this method was developed and validated by the authors and confirmed by many analyses of, known and unknown, wool/cashmere/yak blends at different stages of manufacture (fibres, slivers, yarns, fabrics, and raw materials) and with different treatments (dyed, depigmented, bleached, finished forms).  相似文献   
142.
The possibility to reproduce key tissue functions in vitro from induced pluripotent stem cells (iPSCs) is offering an incredible opportunity to gain better insight into biological mechanisms underlying development and disease, and a tool for the rapid screening of drug candidates. This review attempts to summarize recent strategies for specification of iPSCs towards hepatobiliary lineages —hepatocytes and cholangiocytes—and their use as platforms for disease modeling and drug testing. The application of different tissue-engineering methods to promote accurate and reliable readouts is discussed. Space is given to open questions, including to what extent these novel systems can be informative. Potential pathways for improvement are finally suggested.  相似文献   
143.
To investigate Listeria innocua fate in fresh cut mixed leafy salads, packaged both in ordinary (OA) and modified atmosphere (MA), the type strain DSM 20649 was inoculated and its behaviour was monitored by conventional and molecular approaches, during storage at 4 °C.Results indicated that: fresh cut salads packaged under MA (at initial conditions of 6% CO2 and 3% O2) supported the growth of Listeria spp.; conventional plating technique could not detect L. innocua even into inoculated samples, whereas; PCR–DGGE analysis showed that the L. innocua became one of the dominant species in samples packaged in MA, starting from the 3rd day of storage.The study confirms that modified atmosphere has to be applied together with other preservative techniques in order to assure the inhibition of pathogenic micro-organisms in fresh cut vegetables.  相似文献   
144.
Peptaibols, by disturbing the permeability of phospholipid membranes, can overcome anticancer drug resistance, but their natural hydrophobicity hampers their administration. By a green peptide synthesis protocol, we produced two water-soluble analogs of the peptaibol trichogin GA IV, termed K6-Lol and K6-NH2. To reduce production costs, we successfully explored the possibility of changing the naturally occurring 1,2-aminoalcohol leucinol to a C-terminal amide. Peptaibol activity was evaluated in ovarian cancer (OvCa) and Hodgkin lymphoma (HL) cell lines. Peptaibols exerted comparable cytotoxic effects in cancer cell lines that were sensitive—and had acquired resistance—to cisplatin and doxorubicin, as well as in the extrinsic-drug-resistant OvCa 3-dimensional spheroids. Peptaibols, rapidly taken up by tumor cells, deeply penetrated and killed OvCa-spheroids. They led to cell membrane permeabilization and phosphatidylserine exposure and were taken up faster by cancer cells than normal cells. They were resistant to proteolysis and maintained a stable helical structure in the presence of cancer cells. In conclusion, these promising results strongly point out the need for further preclinical evaluation of our peptaibols as new anticancer agents.  相似文献   
145.
The discovery that receptors from all families can establish allosteric receptor–receptor interactions and variably associate to form receptor complexes operating as integrative input units endowed with a high functional and structural plasticity has expanded our understanding of intercellular communication. Regarding the nervous system, most research in the field has focused on neuronal populations and has led to the identification of many receptor complexes representing an important mechanism to fine-tune synaptic efficiency. Receptor–receptor interactions, however, also modulate glia–neuron and glia–glia intercellular communication, with significant consequences on synaptic activity and brain network plasticity. The research on this topic is probably still at the beginning and, here, available evidence will be reviewed and discussed. It may also be of potential interest from a pharmacological standpoint, opening the possibility to explore, inter alia, glia-based neuroprotective therapeutic strategies.  相似文献   
146.
Al2O3-supported Co3O4 nanosystems were grown by a Chemical Vapor Deposition route under O2 + H2O atmospheres at 500 degrees C. Subsequently, the preparation of Au/Co3O4 composites was attained by Radio Frequency-Sputtering of gold onto the previous Co3O4 nanodeposits. Important data on the system structure, morphology and chemical composition were obtained by the combined use of complementary techniques, namely Glancing Incidence X-ray Diffraction, Field Emission-Scanning Electron Microscopy, Atomic Force Microscopy, Energy Dispersive X-ray Spectroscopy, X-ray Photoelectron Spectroscopy and Secondary Ion Mass Spectrometry. Finally, the gas sensing properties of the synthesized systems were probed in the detection of ethanol and hydrogen. The obtained results revealed significant responses already at moderate temperatures, which could be further enhanced by Co3O4 functionalization with Au nanoparticles.  相似文献   
147.
This paper proposes the application to requirements elicitation of an innovative creativity fostering technique based on a model of the pragmatics of communication, the Elementary Pragmatic Model (EPM). The EPM has been used to define a creative process, called EPMcreate (EPM Creative Requirements Engineering TEchnique) that consists of sixteen steps. In each step, the problem is analyzed according to one elementary behavior identified by the EPM. Each behavior suggests that the analyst look at the problem from a different combination of users’ viewpoints. The feasibility and effectiveness of the technique in requirements elicitation was demonstrated by experiments on two projects with very different characteristics. Each experiment compared the performances of two analysis teams, one of which used EPMcreate and the other of which used brainstorming. The results of both experiments highlights the higher effectiveness of EPMcreate. Additional data from the experiments are examined for other insights into how and why EPMcreate is effective.  相似文献   
148.
Hollow 1-D gold nanostructures with controlled morphology could be readily obtained by RF-sputtering of gold into porous matrices (polycarbonate, polyester), used as scaffolds at low temperatures. Post-synthesis membrane etching by oxygen plasmas or in solution enabled the preparation of free-standing Au nanotubes maintaining the original morphology, that are attractive elements in device structures, such as biosensors for DNA chips or nanoelectrode ensembles. The present results appear extremely promising for the scale-up of different kinds of 1-D materials.  相似文献   
149.
The surface properties of a Ba-β-alumina sample (Ba ∶ Al ratio 1∶ 12) very stable to sintering (15 m2/g after calcination at 1670 K for 10 h) have been investigated by FT-IR spectroscopy of adsorbed probe molecules (water, pyridine and CO2) and by measuring the isoelectric point. The surface has a medium-strong basic character, justified by the preferential exposition of Ba-O-containing “mirror planes”, parallel to 0001 planes, on the surface of plate-like particles. This behavior has been associated to the resistance to sintering, typical of this material, possibly originated by the difficulty of the very big Ba2+ ions to migrate into the spinel-type alumina blocks. This should imply the blocking of the crystal growth along the crystallographicc axis.  相似文献   
150.
Amyotrophic lateral sclerosis (ALS) is a disease with a resilient neuroinflammatory component caused by activated microglia and infiltrated immune cells. How to successfully balance neuroprotective versus neurotoxic actions through the use of anti-inflammatory agents is still under debate. There has been a boost of awareness regarding the role of extracellular ATP and purinergic receptors in modulating the physiological and pathological mechanisms in the nervous system. Particularly in ALS, it is known that the purinergic ionotropic P2X7 receptor plays a dual role in disease progression by acting at different cellular and molecular levels. In this context, we previously demonstrated that the P2X7 receptor antagonist, brilliant blue G, reduces neuroinflammation and ameliorates some of the pathological features of ALS in the SOD1-G93A mouse model. Here, we test the novel, noncommercially available, and centrally permeant Axxam proprietary P2X7 antagonist, AXX71, in SOD1-G93A mice, by assessing some behavioral and molecular parameters, among which are disease progression, survival, gliosis, and motor neuron wealth. We demonstrate that AXX71 affects the early symptomatic phase of the disease by reducing microglia-related proinflammatory markers and autophagy without affecting the anti-inflammatory markers or motor neuron survival. Our results suggest that P2X7 modulation can be further investigated as a therapeutic strategy in preclinical studies, and exploited in ALS clinical trials.  相似文献   
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