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Cartilage tissue lines the joints of mammals, helping to lubricate joint movement and distribute mechanical loads. This tissue is comprised of isolated cells known as chondrocytes which are embedded in an extracellular matrix. Chondrocytes produce and maintain the cartilage by sensing and responding to changing mechanical loads. Mechanosensitive ion channels have been implicated in chondrocyte mechanotransduction and recent studies have shown that both PIEZO1 and TRPV4 can be activated by mechanical stimuli in these cells. The 2 channels mediate separate but overlapping mechanoelectrical transduction pathways, PIEZO1 in response to stretch and substrate deflections and TRPV4 in response to substrate deflections alone. These distinct pathways of mechanoelectrical transduction suggest a mechanism by which chondrocytes can distinguish between different stimuli that arise in their complex mechanical environment.  相似文献   
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We demonstrate the coating of tablets using an injection molding (IM) process that has advantage of being solvent free and can provide precision coat features. The selected core tablets comprising 10% w/w griseofulvin were prepared by an integrated hot melt extrusion-injection molding (HME-IM) process. Coating trials were conducted on a vertical injection mold machine. Polyethylene glycol and polyethylene oxide based hot melt extruded coat compositions were used. Tablet coating process feasibility was successfully demonstrated using different coating mold designs (with both overlapping and non-overlapping coatings at the weld) and coat thicknesses of 150 and 300?μm. The resultant coated tablets had acceptable appearance, seal at the weld, and immediate drug release profile (with an acceptable lag time). Since IM is a continuous process, this study opens opportunities to develop HME-IM continuous processes for transforming powder to coated tablets.  相似文献   
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During the past decades, lipid nanocarriers are gaining momentum with their multiple advantages for the management of skin diseases. Lipid nanocarriers enable to target the therapeutic payload to deep skin layers or even to reach the blood circulation making them a promising cutting-edge technology.Lipid nanocarriers refer to a large panel of drug delivery systems. Lipid vesicles are the most conventional, known to be able to carry lipophilic and hydrophilic active agents. A variety of lipid vesicles with high flexibility and deformability could be obtained by adjusting their composition; namely ethosomes, transfersomes and penetration enhancer lipid vesicles which achieve the best results in term of skin permeation. Others are designed with the objective to perform higher encapsulation rate and higher stability, such as solid lipid nanoparticles and nanostructured lipid nanocarriers.In this review, we attempted to give an overview of lipid based nanocarriers developed with the aim to enhance dermal and transdermal drug delivery. A special focus is put on the nanocarrier composition, behavior and interaction mechanisms with the skin. Recent applications of lipid-based nanocarriers for the management of skin diseases and other illnesses are highlighted as well.  相似文献   
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Aims: An Ecological approach to alcohol behaviour focuses on understanding individual–environment transactions, rather than on cognitive antecedents of behaviour. Meaning exists in the interdependence of individuals and their environments, in terms of affordances. Through subjective experience, this study focussed on group viewpoints related to alcohol-related affordances, or opportunities to consume alcohol in shared drinking environments. Methods: Forty students with a range of self-reported drinking behaviours participated in a Q-Methodology study, ranking 60 statements along a symmetrical grid. This varied concourse of alcohol-related affordances was obtained from a previous observation study within licenced premises and a photo-elicitation interview study with drinkers. Findings: Factor analysis and post-sort interviews revealed four subjective perspectives held by groups about their drinking behaviour: 13 participants were aware of contextual influences, but autonomous in their drinking choices; 12 participants were conscious of influences and compliant to their effects; six participants were unaware of influences, but unanimous with their peers; two participants were concerned about acting appropriately in a context by taking up canonical affordances. Conclusions: Grouping subjectivities from a varied concourse of affordances can reveal subjective experience in relation to drinking environments and alcohol behaviour. This conceptual approach for understanding drinking behaviour should be studied further.  相似文献   
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