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51.
The purpose of this study was to investigate the variability in the performance of a pulsatile capsule delivery system induced by wet granulation of an erodible HPMC tablet, used to seal the contents within an insoluble capsule body. Erodible tablets containing HPMC and lactose were prepared by direct compression (DC) and wet granulation (WG) techniques and used to seal the model drug propranolol inside an insoluble capsule body. Dissolution testing of capsules was performed. Physical characterisation of the tablets and powder blends used to form the tablets was undertaken using a range of experimental techniques. The wet granulations were also examined using the novel technique of microwave dielectric analysis (MDA). WG tablets eroded slower and produced longer lag-times than those prepared by DC, the greatest difference was observed with low concentrations of HPMC. No anomalous physical characteristics were detected with either the tablets or powder blends. MDA indicated water-dipole relaxation times of 2.9, 5.4 and 7.7x10(-8)ms for 15, 24 and 30% HPMC concentrations, respectively, confirming that less free water was available for chain disentanglement at high concentrations. In conclusion, at low HPMC concentrations water mobility is at its greatest during the granulation process, such formulations are therefore more sensitive to processing techniques. Microwave dielectric analysis can be used to predict the degree of polymer spreading in an aqueous system, by determination of the water-dipole relaxation time.  相似文献   
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It has been previously suggested that morphine can regulate the expression and function of some proteins of the cytoskeleton. In the present study, we used real-time quantitative polymerase chain reaction to examine the effects of chronic morphine administration, in rat striatum, on 14 proteins involved in microtubule polymerization and stabilization, intracellular trafficking, and serving as markers of neuronal growth and degeneration. Chronic morphine treatment led to modulation of the mRNA level of seven of the 14 genes tested. Glial fibrillary acidic protein (Gfap) and activity-regulated cytoskeleton-associated protein (Arc) mRNA were upregulated, while growth associated protein (Gap43), clathrin heavy chain (Cltc), alpha-tubulin, Tau, and stathmin were downregulated. In order to determine if the regulation of an mRNA correlates with a modulation of the expression of the corresponding protein, immunoblot analyses were performed. With the exception of Gap43, the levels of Cltc, Gfap, Tau, stathmin, and alpha-tubulin proteins were found to be in good agreement with those from mRNA quantification. These results demonstrate that neuroadaptation to chronic morphine administration in rat striatum implies modifications of the expression pattern of several genes and proteins of the cytoskeleton and cytoskeleton-associated components.  相似文献   
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The phosphatidylinositol‐3‐kinase (PI3K)/AKT/mammalian target of rapamycin (mTOR) pathway is frequently activated in HER2‐negative breast cancer and may play a role in taxane resistance. The phase IB/II TAKTIC trial (NCT01980277) has shown that combining a dual AKT and p70 ribosomal protein S6 kinase (p70S6K) inhibitor (LY2780301) taken orally with weekly paclitaxel in HER2‐negative advanced breast cancer is feasible, with preliminary evidence of efficacy. We wanted to explore whether circulating tumor DNA (ctDNA) may be a surrogate marker of treatment efficacy in this setting. Serial plasma samples were collected and cell‐free DNA was sequenced using low‐coverage whole‐genome sequencing, and analysis was completed with droplet digital polymerase chain reaction (PCR) for some patients with driver mutations. Baseline tumor fraction (TF) and TF after 7 weeks on treatment were compared to progression‐free survival (PFS) and the overall response rate. We also explored circulating copy number alterations associated with treatment failure. Of the 51 patients enrolled in the TAKTIC trial, at least one plasma sample was available for 44 cases (96 timepoints). All patients with tumor TP53, PI3KCA, or AKT1 mutations harbored at least one of these alterations in plasma. TF at inclusion was correlated with PFS (6m‐PFS was 92% for ctDNAneg patients vs 68% for ctDNApos cases; hazard ratio [HR] = 3.45, 95% confidence interval [CI] [1.34–8.90], P = 0.007). ctDNA status at week 7 was not correlated with prognosis. Even though most circulating copy number alterations were conserved at disease progression, some genomic regions of interest were altered in post‐progression samples. In conclusion, ctDNA detection at baseline was associated with shorter PFS in patients included in the TAKTIC trial. Plasma‐based copy number analysis may help to identify alterations involved in resistance to treatment.  相似文献   
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In material-resource poor countries like Mali, traditional practices incorporate the use of plants for medicinal purposes. Ethnobotanical research has documented traditional uses of plants, while concomitant studies by natural product chemists, ethnobotanists, and microbiologists have verified the efficacy of using traditional medicinal plants that have proven antimicrobial activity. These plants may also be used to protect agricultural crops pre-harvest and post-harvest from insect herbivory. In Mali, subsistence farmers, regional scientists, and extension specialists rely on local plants for many medicinal needs and are amenable to using traditional plant materials for insect pest management. The goal of this research was to develop Integrated Pest Management (IPM) strategies using Malian traditional medicine as a discovery lead. The discovery premise was based on identifying plants through a matrix approach utilizing agricultural scientists, traditional practitioners, and subsistence farmers. We hypothesized that plants used in traditional medicine with antimicrobial activity lead to potential insect pest management agents. To test our hypothesis, we developed a four-step process for selecting Malian plant species. Seven criteria were selected to create a systematic matrix to identify the most promising plant materials for practical, affordable, ecologically-sound insect management by Malian farmers. In the first step of the process, we developed a list of 294 medicinal Malian plant species which were evaluated using the matrix. Sixty-seven plant species met our main criteria. After the environmental soundness of these species was evaluated using four minor criteria, 50 species emerged from this pre-chemical, pre-bioassay process for further consideration in IPM programs in Mali.  相似文献   
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Documenta Ophthalmologica - Neuronal ceroid lipofuscinoses (CLN) are neurodegenerative disorders among the most frequent, inherited as an autosomal recessive trait. Affected patients can present...  相似文献   
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Objective: Several biologic therapies are available for the treatment of mild-to-moderate Crohn’s disease (CD). This network meta-analysis (NMA) aimed to assess the comparative efficacy of ustekinumab, adalimumab, vedolizumab and infliximab in the maintenance of clinical response and remission after 1?year of treatment.

Methods: A systematic literature search was performed to identify relevant randomized controlled trials (RCTs). Key outcomes of interest were clinical response (CD activity index [CDAI] reduction of 100 points; CDAI-100) and remission (CDAI score under 150 points; CDAI < 150). A treatment sequence Bayesian NMA was conducted to account for the re-randomization of patients based on different clinical definitions, the lack of similarity of the common comparator for each trial and the full treatment pathway from the induction phase onwards.

Results: Thirteen RCTs were identified. Ustekinumab 90?mg q8w was associated with statistically significant improvement in clinical response relative to placebo and vedolizumab 300?mg. For clinical remission, ustekinumab 90?mg q8w was associated with statistically significant improvement relative to placebo and vedolizumab 300?mg q8w. Findings from sub-population analyses had similar results but were not statistically significant.

Conclusions: The NMA suggest that ustekinumab is associated with the highest likelihood of reaching response or remission at 1?year compared with placebo, adalimumab and vedolizumab. Results should be interpreted with caution because this is a novel methodology; however, the treatment sequence analysis may be the most methodologically sound analysis to derive estimates of comparative efficacy in CD in the absence of head-to-head evidence.  相似文献   

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Objectives Film coatings based on blends of Eurylon 6 HP‐PG (a hydroxypropylated and pregelatinized high amylose starch) and ethylcellulose were to be evaluated as promising coating materials for site‐specific drug delivery to the colon of patients suffering from inflammatory bowel diseases. Methods Pellet starter cores containing 60% 5‐aminosalicylic acid were prepared by extrusion/spheronization and coated with different Eurylon 6 HP‐PG : ethylcellulose blends at various coating levels. Drug release was measured in media simulating the contents of the upper gastrointestinal tract (in the presence and absence of enzymes) as well as in media simulating the contents of the colon. Key findings 5‐Aminosalicylic acid release could effectively be suppressed in 0.1 N HCl and phosphate buffer pH 6.8, optionally containing pepsin or pancreatin, but occurred as soon as the pellets came into contact with culture medium inoculated with faecal samples from inflammatory bowel disease patients. This can be attributed to the partial degradation of the starch derivative by enzymes secreted by bacteria present in the colon of these patients. Conclusions The presented drug delivery system is adapted to the pathophysiological conditions in inflammatory bowel disease patients. Furthermore, drug release remained unaltered upon 1 year open storage.  相似文献   
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