1,421 research outputs found
Formulation and characterization of an apigenin-phospholipid phytosome (APLC) for improved solubility, in vivo bioavailability, and antioxidant potential
The apigenin-phospholipid phytosome (APLC) was developed to improve the aqueous solubility, dissolution, in vivo bioavailability, and antioxidant activity of apigenin. The APLC synthesis was guided by a full factorial design strategy, incorporating specific formulation and process variables to deliver an optimized product. The design-optimized formulation was assayed for aqueous solubility, in vitro dissolution, pharmacokinetics, and antioxidant activity. The pharmacological evaluation was carried out by assessing its effects on carbon tetrachloride-induced elevation of liver function marker enzymes in a rat model. The antioxidant activity was assessed by studying its effects on the liver antioxidant marker enzymes. The developed model was validated using the design-optimized levels of formulation and process variables. The physical-chemical characterization confirmed the formation of phytosomes. The optimized formulation demonstrated over 36-fold higher aqueous solubility of apigenin, compared to that of pure apigenin. The formulation also exhibited a significantly higher rate and extent of apigenin release in dissolution studies. The pharmacokinetic analysis revealed a significant enhancement in the oral bioavailability of apigenin from the prepared formulation, compared to pure apigenin. The liver function tests indicated that the prepared phytosome showed a significantly improved restoration of all carbon tetrachloride-elevated rat liver function marker enzymes. The prepared formulation also exhibited antioxidant potential by significantly increasing the levels of glutathione, superoxide dismutase, catalase, and decreasing the levels of lipid peroxidase. The study shows that phospholipid-based phytosome is a promising and viable strategy for improving the delivery of apigenin and similar phytoconstituents with low aqueous solubility
Quantitative nucleotide level analysis of regulation of translation in response to depolarization of cultured neural cells
Studies on regulation of gene expression have contributed substantially to understanding mechanisms for the long-term activity-dependent alterations in neural connectivity that are thought to mediate learning and memory. Most of these studies, however, have focused on the regulation of mRNA transcription. Here, we utilized high-throughput sequencing coupled with ribosome footprinting to globally characterize the regulation of translation in primary mixed neuronal-glial cultures in response to sustained depolarization. We identified substantial and complex regulation of translation, with many transcripts demonstrating changes in ribosomal occupancy independent of transcriptional changes. We also examined sequence-based mechanisms that might regulate changes in translation in response to depolarization. We found that these are partially mediated by features in the mRNA sequence—notably upstream open reading frames and secondary structure in the 5′ untranslated region—both of which predict downregulation in response to depolarization. Translationally regulated transcripts are also more likely to be targets of FMRP and include genes implicated in autism in humans. Our findings support the idea that control of mRNA translation plays an important role in response to neural activity across the genome
Glucosamine HCl-based solid dispersions to enhance the biopharmaceutical properties of acyclovir
The objective of the work presented here was to assess the feasibility of using glucosamine HCl as a solid-dispersion (SD) carrier to enhance the biopharmaceutical properties of a BCS class III/IV drug, acyclovir (ACV). The solid-dispersions of acyclovir and glucosamine HCl were prepared by an ethanol-based solvent evaporation method. The prepared formulations characterized by photomicroscopy, scanning electron microscopy (SEM), differential scanning calorimetry (DSC), Fourier transforms infrared spectrophotometry (FTIR), powder x-ray diffractometry (PXRD) and drug content analysis. The functional characterization of ACV-SD was performed by aqueous solubility evaluation, dissolution studies, fasted versus fed state dissolution comparison, ex vivo permeability, and stability studies. Photomicroscopy and SEM analysis showed different surface morphologies for pure ACV, glucosamine HCl and ACV-SD. The physical-chemical characterization studies supported the formation of ACV-SD. A 12-fold enhancement in the aqueous solubility of ACV was observed in the prepared solid dispersions, compared to pure ACV. Results from in vitro dissolution demonstrated a significant increase in the rate and extent of ACV dissolution from the prepared ACV-SD formulations, compared to pure ACV. The rate and extent of ACV permeability across everted rat intestinal membrane were also found to be significantly increased in the ACV-SD formulations. Under fed conditions, the rate and extent of the in vitro dissolution of ACV from the formulation was appreciably greater compared to fasted conditions. Overall, the results from the study suggest the feasibility of utilizing glucosamine HCl as a solid dispersion carrier/excipient for enhancement of biopharmaceutical properties of acyclovir, and similar drugs with low solubility/permeability characteristics
Kaempferol-Phospholipid Complex: Formulation, and Evaluation of Improved Solubility, In Vivo Bioavailability, and Antioxidant Potential of Kaempferol
The current work describes the formulation and evaluation of a phospholipid complex of kaempferol toenhance the latter’s aqueous solubility, in vitro dissolution rate, in vivo antioxidant and hepatoprotectiveactivities, and oral bioavailability. The kaempferol-phospholipid complex was synthesized using a freeze-drying method with the formulation being optimized using a full factorial design (32) approach. The resultsinclude the validation of the mathematical model in order to ascertain the role of specific formulation andprocess variables that contribute favorably to the formulation’s development. The final product wascharacterized and confirmed by Differential Scanning Calorimetry (DSC), Fourier Transform InfraredSpectroscopy (FTIR), Proton Nuclear Magnetic Resonance Spectroscopy (1H-NMR), and Powder X-rayDiffraction (PXRD) analysis. The aqueous solubility and the in vitro dissolution rate were enhanced comparedto that of pure kaempferol. The in vivo antioxidant properties of the kaempferol-phospholipid complex wereevaluated by measuring its impact on carbon tetrachloride (CCl4)-intoxicated rats. The optimizedphospholipid complex improved the liver function test parameters to a significant level by restoration of allelevated liver marker enzymes in CCl4-intoxicated rats. The complex also enhanced the in vivo antioxidantpotential by increasing levels of GSH (reduced glutathione), SOD (superoxide dismutase), catalase anddecreasing lipid peroxidation, compared to that of pure kaempferol. The final optimized phospholipidcomplex also demonstrated a significant improvement in oral bioavailability demonstrated by improvementsto key pharmacokinetic parameters, compared to that of pure kaempferol
Magnetoelectricity at room temperature in Bi0.9-xTbxLa0.1FeO3 system
Magnetoelectric compounds with the general formula, Bi0.9-xRxLa0.1FeO3 (R
=Gd, Tb, Dy, etc.), have been synthesized. These show the coexistence of
ferroelectricity and magnetism, possess high dielectric constant and exhibit
magnetoelectric coupling at room temperature. Such materials may be of great
significance in basic as well as applied research.Comment: 11 pages of text and figure
Cell-type-specific profiling of alternative translation identifies regulated protein isoform variation in the mouse brain
SETD3 is an actin histidine methyltransferase that prevents primary dystocia.
For more than 50 years, the methylation of mammalian actin at histidine 73 has been known to occur1. Despite the pervasiveness of His73 methylation, which we find is conserved in several model animals and plants, its function remains unclear and the enzyme that generates this modification is unknown. Here we identify SET domain protein 3 (SETD3) as the physiological actin His73 methyltransferase. Structural studies reveal that an extensive network of interactions clamps the actin peptide onto the surface of SETD3 to orient His73 correctly within the catalytic pocket and to facilitate methyl transfer. His73 methylation reduces the nucleotide-exchange rate on actin monomers and modestly accelerates the assembly of actin filaments. Mice that lack SETD3 show complete loss of actin His73 methylation in several tissues, and quantitative proteomics analysis shows that actin His73 methylation is the only detectable physiological substrate of SETD3. SETD3-deficient female mice have severely decreased litter sizes owing to primary maternal dystocia that is refractory to ecbolic induction agents. Furthermore, depletion of SETD3 impairs signal-induced contraction in primary human uterine smooth muscle cells. Together, our results identify a mammalian histidine methyltransferase and uncover a pivotal role for SETD3 and actin His73 methylation in the regulation of smooth muscle contractility. Our data also support the broader hypothesis that protein histidine methylation acts as a common regulatory mechanism
A systematic review of psychosocial therapies for children with rheumatic diseases
BACKGROUND: To assess the quality of evidence for the effects of psychosocial therapies on pain and function in children with rheumatic diseases. METHODS: We conducted a literature search of MEDLINE and PsycINFO for randomized clinical trials of psychosocial interventions for pain and disability in children with rheumatic diseases from January 1969 to September 2015. Studies with a sample size less than 10 subjects were excluded. Study quality was assessed using the Jadad score. RESULTS: Five articles met inclusion criteria, for a total of 229 patients, aged 5 to 18 years. Two studies included children with fibromyalgia. Three studies included children with juvenile arthritis. Neither study in fibromyalgia reported the statistical significance of immediate between-group pre-post changes in functioning or pain. One study examining the effects of an internet-based psychosocial intervention in children with juvenile arthritis reported significant differences in post-intervention pain scores (p = 0.03). However, 2 studies did not show improvements in pain scores among children with juvenile arthritis treated with psychosocial interventions vs. a wait-list control or vs. an active control (massage). No studies reported significant between-group differences for functional outcomes in children with juvenile arthritis. CONCLUSIONS: The available data were limited by the scarcity of randomized trials. Definite conclusions about the immediate effect of psychosocial interventions on pain and function in children with fibromyalgia could not be made because between-group comparisons of post-treatment change scores were not reported. For children with juvenile inflammatory arthritis, results of between-group comparisons for pain differed across studies, and analyses examining disability revealed no significant differences between groups
Priority projects for the implementation of CCS power generation with enhanced oil recovery in Mexico
In March 2014, Mexico launched its CCUS technology roadmap, outlining the actions to be taken up to 2024. One important action is the National Policy of Carbon Capture and Storage (CCS) ready and the identification of priority natural gas combined cycle (NGCC) with capture plants. This outcome could aid the creation of a technology roadmap for the design of new NGCC power plants and their operational requirements for EOR and for the reduction of CO 2 emissions. This article provides an overview of the opportunities for deploying CCS in new NGCC power plants in Mexico which were programed to begin operation throughout the period from 2016 to 2030. The attention is given to plants close to oil fields which are candidates for enhanced oil recovery (EOR), located in an inclusion zone suitable for storage. The Gulf of Mexico region, where potential EOR sites and the presence of industrial CO 2 sources are located, is within the inclusion zone for recommended sites for geological storage of CO 2 . After identifying new power plants in the inclusion zone, this article analyses which existing plants could be retrofitted and which new power plants could be designed to be ‘carbon capture ready’. In addition, the distance and the volumes of CO 2 are estimated
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