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91.
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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Metabolic syndrome (MetS) is seen more frequently in persons with schizophrenia than in the general population, and these metabolic abnormalities are further aggravated by second generation antipsychotic (SGA) drugs. Although the underlying mechanisms responsible for the increased prevalence of MetS among patients under SGA treatment are not well understood, alterations in mitochondria function have been implicated. We performed a comprehensive evaluation of the role of mitochondrial dysfunction in the pathophysiology of drug-induced MetS in schizophrenia. We found a downregulation in genes encoding subunits of the electron transport chain complexes (ETC), enzyme activity, and mitochondrial dynamics in peripheral blood cells from patients at high-risk for MetS. Additionally, we evaluated several markers of energy metabolism in lymphoblastoid cell lines from patients with schizophrenia and controls following exposure to antipsychotics. We found that the high-risk drugs clozapine and olanzapine induced a general down-regulation of genes involved in the ETC, as well as decreased activities of the corresponding enzymes, ATP levels and a significant decrease in all the functional parameters of mitochondrial oxygen consumption in cells from patients and controls. We also observed that the medium-risk SGA quetiapine decreased oxygen consumption and respiratory control ratio in controls and patients. Additionally, clozapine and olanzapine induced a downregulation of Drp1 and Mfn2 both in terms of mRNA and protein levels. Together, these data suggest that an intrinsic defect in multiple components of oxidative metabolism may contribute to the increased prevalence of MetS in patients under treatment with SGAs known to cause risk for MetS.  相似文献   
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Oxidative stress and inflammation are intricately interlinked as aetiological factors in the context of ageing and chronic disease-related accelerated ageing. Previous research by our group has highlighted the anti-oxidant and anti-inflammatory potential of grape-derived polyphenols in the context of acute inflammation and oxidative stress. The aim here was to add to this by assessing efficacy of the treatment (acutely) to address ageing-associated cumulative pro-oxidant and pro-inflammatory changes in an in vitro model. Blood from young and aged humans was analysed for baseline oxidative stress and inflammatory status. Isolated neutrophils were acutely exposed to the polyphenol treatment in vitro. The chemokinetic capacity of treated and control neutrophils in response to fMLP was subsequently determined in a Dunn chamber, using live cell imaging. Neutrophils were also analysed for the expression of selected molecular markers associated with functional capacity and oxidative stress. Results indicate that the aged population had significantly worse oxidative stress and inflammatory profiles (higher plasma conjugated dienes and MPO) than young controls. Neutrophils isolated from both young and aged individuals had improved chemokinetic accuracy and capacity after in vitro polyphenol treatment. Additionally, increased shedding of CD16 and expression of CD66b suggested sites via which the polyphenol achieved improved neutrophil motility. We conclude that grape seed-derived polyphenols facilitated improved neutrophil functionality by acting on the molecular targets elucidated here.  相似文献   
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Aim To investigate the effect of squalene on LDLR expression in HepG2 cells and its mechanism of down-regulated cholesterol. Methods The proliferation of HepG2 cells exposed to squalene at different concentrations was measured by MTT assay. The effect of squalene on the expression of LDLR in HepG2 cells was measured by flow cytometry and fluorescence mi-croscopy. The effect of different concentrations of squalene on the interaction between SCAP and Insig2, two key protein molecules of SREBP pathway, was assayed by FRET technology. Results MTT results showed that squalene had inhibitory effect on the proliferation of HepG2 cells in a dose-dependent manner. Flow cytometry and fluorescence microscopy results showed that squalene enhanced LDLR expression in HepG2 cells compared with the control group. The results of FRET technology revealed that compared with model control group, the YFP fluorescence value in Squalene group dramatically declined, and the YFP fluorescence value of each drug group decreased with the range of 5-25 |xmol L1 squalene concentration. Conclusions Squalene may promote the expression of LDLR in HepG2 cells through inhibiting the interaction between SCAP and Insig2 proteins in SREBP pathway, which may confirm that squalene is a potential novel drug for the down-regulation of cholesterol level. © 2018 Publication Centre of Anhui Medical University. All rights reserved.  相似文献   
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Extracellular vesicles (EV) are secreted signaling entities that enhance various pathological processes when released in response to cellular stresses. Respiratory exposures such as cigarette smoke and air pollution exert cellular stresses and are associated with an increased risk of several chronic diseases. The aim of this review was to examine the evidence that modifications in EV contribute to respiratory exposure-associated diseases. Publications were searched using PubMed and Google Scholar with the search terms (cigarette smoke OR tobacco smoke OR air pollution OR particulate matter) AND (extracellular vesicles OR exosomes OR microvesicles OR microparticles OR ectosomes). All original research articles were included and reviewed. Fifty articles were identified, most of which investigated the effect of respiratory exposures on EV release in vitro (25) and/or on circulating EV in human plasma (24). The majority of studies based their main observations on the relatively insensitive scatter-based flow cytometry of EV (29). EV induced by respiratory exposures were found to modulate inflammation (19), thrombosis (13), endothelial dysfunction (11), tissue remodeling (6), and angiogenesis (3). By influencing these processes, EV may play a key role in the development of cardiovascular diseases and chronic obstructive pulmonary disease and possibly lung cancer and allergic asthma. The current findings warrant additional research with improved methodologies to evaluate the contribution of respiratory exposure-induced EV to disease etiology, as well as their potential as biomarkers of exposure or risk and as novel targets for preventive or therapeutic strategies.  相似文献   
100.

Background

Hospitalization can contribute to insomnia in many patients and is usually treated symptomatically. However, sedative/hypnotic misuse is associated with complications in this population, especially in the elderly. Such complications include dizziness, falls and over-sedation. Due to the implicit dangers, widespread use of these drugs for insomnia, particularly in older patients, has been discouraged by many hospitals. The aim of this study was to review and evaluate prescribing patterns and to optimize the use of the sedative/hypnotic agents through daily pharmacy interventions at a community hospital.

Methods

This was a biphasic before and after study. Data on sedative/hypnotic use was collected retrospectively for a 2-month period and a sample of 100 patients was randomly selected for analysis. A 2-month prospective phase followed, in which daily orders were reviewed by one pharmacy resident and recommendations made to discontinue any unnecessary, newly prescribed sedative/hypnotic orders when appropriate. Finally, results of both phases were compared for any differences in patient demographics, being prescribed more than one sedative/hypnotic, and complications documented.

Results

During the prospective phase, pharmacist interventions led to the discontinuation of 25% of a total of 97 sedative/hypnotic orders in 97 patients. The number of patients receiving more than one sedative/hypnotic agents in the intervention group was significantly lower than the retrospective control group (15 Vs. 34, P?=?0.0026). The incidence of complications was not significantly different between the control and intervention groups for the following: over-sedation, falls and delirium (p?=?0.835, p?=?0.185, p?=?0.697, respectively).

Conclusion

This study suggests that the use of sedative/hypnotics in the inpatient units (excluding the critical care unit), is somewhat prevalent, and many patients may be on more than one sedative/hypnotic, which could potentially cause cumulative harm. During the intervention phase, 25% of the total in-hospital orders for sedative/hypnotics were discontinued following recommendations made by a pharmacist, and significantly lower number of patients receiving duplicate sedative/hypnotics was noted. Further efforts should be implemented to avoid unnecessary sedative/hypnotic initiation in hospitalized patients, and to ensure monitoring by pharmacists is optimized.  相似文献   
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