119 research outputs found
Estrogen treatment decreases matrix metalloproteinase (MMP)-9 in autoimmune demyelinating disease through estrogen receptor alpha (ERalpha).
Matrix metalloproteinases (MMPs) have a crucial function in migration of inflammatory cells into the central nervous system (CNS). Levels of MMP-9 are elevated in multiple sclerosis (MS) and predict the occurrence of new active lesions on magnetic resonance imaging (MRI). This translational study aims to determine whether in vivo treatment with the pregnancy hormone estriol affects MMP-9 levels from immune cells in patients with MS and mice with experimental autoimmune encephalomyelitis (EAE). Peripheral blood mononuclear cells (PBMCs) collected from three female MS patients treated with estriol and splenocytes from EAE mice treated with estriol, estrogen receptor (ER) alpha ligand, ERbeta ligand or vehicle were stimulated ex vivo and analyzed for levels of MMP-9. Markers of CNS infiltration were assessed using MRI in patients and immunohistochemistry in mice. Supernatants from PBMCs obtained during estriol treatment in female MS patients showed significantly decreased MMP-9 compared with pretreatment. Decreases in MMP-9 coincided with a decrease in enhancing lesion volume on MRI. Estriol treatment of mice with EAE reduced MMP-9 in supernatants from autoantigen-stimulated splenocytes, coinciding with decreased CNS infiltration by T cells and monocytes. Experiments with selective ER ligands showed that this effect was mediated through ERalpha. In conclusion, estriol acting through ERalpha to reduce MMP-9 from immune cells is one mechanism potentially underlying the estriol-mediated reduction in enhancing lesions in MS and inflammatory lesions in EAE
METHOD DEVELOPMENT AND VALIDATION FOR THE ESTIMATION OF ENTECAVIR IN BULK AND PHARMACEUTICAL DOSAGE FORMS BY RP-HPLC
Objective: The objective and purpose of the analysis have sensibly assessed by selecting of a rapid and sensitive RP-HPLC method for Entecavir in bulk and pharmaceutical dosage form by using the most commonly employed C-18column with UV detection.Methods: In estimation by RP-HPLC method Agilent 1120 compact LC system with variable programmable UV detector and Rheodyne injector with 20 µl fixed loop was used for the chromatographic separation. The mode of operation was isocratic with the components of a solution consisting of methanol: acetonitrile(70:30v/v) and triethanolamine (2-4drops)at the flow rate of 1.2 ml/min and run time was 10 min. Forced degradation studies were conducted to evaluate the stability and specificity of the method along with the validation parameters.Results: Validation parameters of HPLC were found at a detection wavelength of 255 nm. Linearity was observed with the concentration range (Beer's law range) 20-100µg/ml with R2=0.9991. Robustness with detection wavelengths 253 and 257 nm with a flow rate of 1 ml/min and 1.4 ml/min showed good results. The retention time of the drug was 2.64 min and assay showed 98.1%.Conclusion: The proposed RP-HPLC method was validated as per the ICH Q2B Guidelines, and was found to be applicable for routine quantitative analysis of Entecavir by RP-HPLC using UV detector in pharmaceutical dosage forms. The results of linearity, precision, accuracy and specificity, were proved, that does not exceed certain specified limits. The method provides selective quantification with no interference from other formulation excipients. The proposed method was highly sensitive, reproducible, reliable, robust and specific. Therefore, this method is a simple, rapid analysis may actually be more desirable than a more complicated and time-consuming process. The degradation studies at various stress conditions like thermal and hydrolytic, drug gets degraded at a temperature of 80 °c and refluxing with water at 70 °c for 24hours.Â
Development of Functional Polyurethane–ZnO Hybrid Nanocomposite Coatings from Thevetia peruviana Seed Oil
The present article reports eco-friendly multifunctional
polyurethane–ZnO hybrid nanocomposite coatings
obtained from Thevetia peruviana seed oil (TPSO).
Initially, the polyols were prepared by treating TPSO with
glycerol and the formation was supported by Fourier transform
infrared (FT-IR) and 1H-NMR studies. In the next
stage, siloxane functionalized ZnO nanoparticles were
added to the polyol mixture in different weight percentages
(0, 1 and 2 %) and then treated with excess 4,4′-diisocyanatodicyclohexylmethane
(H12MDI) in order to synthesize
isocyanate terminated polyurethane nanocomposites.
The polyurethane hybrids were then casted as thin films
and cured under atmospheric moisture. After complete
curing they were characterized by using FT-IR, 1H-NMR,
13C-NMR, X-ray diffraction, scanning electron microscopy,
thermogravimetric analysis, and dynamic mechanical
thermal analysis techniques. The hybrid nanocomposites
showed superior thermo-mechanical and anti-corrosive
properties compared to pristine polyurethane. Also, due
to the presence of nano ZnO in the polyurethane matrix,the composite coatings are showing excellent resistance
towards various bacterial and fungal stains
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Therapeutic laquinimod treatment decreases inflammation, initiates axon remyelination, and improves motor deficit in a mouse model of multiple sclerosis.
BackgroundTherapeutic strategies that induce effective neuroprotection and enhance intrinsic repair mechanisms are central goals for future treatment of multiple sclerosis (MS), as well as other diseases. Laquinimod (LQ) is an orally administered, central nervous system (CNS)-active immunomodulator with demonstrated efficacy in MS clinical trials and a favorable safety and tolerability profile.AimsWe aimed to explore the pathological, functional, and behavioral consequences of prophylactic and therapeutic (after presentation of peak clinical disease) LQ treatment in the chronic experimental autoimmune encephalomyelitis (EAE) mouse model of MS.Materials and methodsActive EAE-induced 8-week-old C57BL/6 mice were treated with 5 or 25 mg/kg/day LQ via oral gavage beginning on EAE post-immunization day 0, 8, or 21. Clinical scores and rotorod motor performance were assessed throughout the disease course. Immune analysis of autoantigen-stimulated splenocytes, electrophysiological conduction of callosal axons, and immunohistochemistry of white matter-rich corpus callosum and spinal cord were performed.ResultsProphylactic and therapeutic treatment with LQ significantly decreased mean clinical disease scores, inhibited Th1 cytokine production, and decreased the CNS inflammatory response. LQ-induced improvement in axon myelination and integrity during EAE was functional, as evidenced by significant recovery of callosal axon conduction and axon refractoriness and pronounced improvement in rotorod motor performance. These improvements correlate with LQ-induced attenuation of EAE-induced demyelination and axon damage, and improved myelinated axon numbers.DiscussionEven when initiated at peak disease, LQ treatment has beneficial effects within the chronic EAE mouse model. In addition to its immunomodulatory effects, the positive effects of LQ treatment on oligodendrocyte numbers and myelin density are indicative of significant, functional neuroprotective and neurorestorative effects.ConclusionsOur results support a potential neuroprotective, in addition to immunomodulatory, effect of LQ treatment in inhibiting ongoing MS/EAE disease progression
Deep learning framework for uncovering compositional and environmental contributions to pitting resistance in passivating alloys
We have developed a deep-learning-based framework for understanding the individual and mutually combined contributions of different alloying elements and environmental conditions towards the pitting resistance of corrosion-resistant alloys. A fully connected deep neural network (DNN) was trained on previously published datasets on corrosion-relevant electrochemical metrics, to predict the pitting potential of an alloy, given the chemical composition and environmental conditions. Mean absolute error of 170 mV in the predicted pitting potential, with an R-square coefficient of 0.61 was obtained after training. The trained DNN model was used for multi-dimensional gradient descent optimization to search for conditions maximizing the pitting potential. Among environmental variables, chloride-ion concentration was universally found to be detrimental. Increasing the amounts of dissolved nitrogen/carbon was found to have the strongest beneficial influence in many alloys. Supersaturating transition metal high entropy alloys with large amounts of interstitial nitrogen/carbon has emerged as a possible direction for corrosion-resistant alloy design
Allocation and Inventory Policies for Reels in Printed Circuit Board Assemblies
In Printed Circuit Board (PCB) assemblies, various types of reels loaded with different components are extensively utilized. We examine the inventory and allocation policies across assembly lines when the number and size of the reels substantially affect the assembly efficiency (e.g., when the number of available slots in a chip shooter is relatively limited). Critical features of the policies are illustrated via numerical examples
Thermal Stability and Antibacterial Activity of a Newly Prepared Organic Coating from a De-saturated Seed Oil of Thevetia Peruviana
Air drying polyesteramide-urethanes resins were synthesized from de-saturated fatty methyl ester
(FAME) of Thevetia peruviana seed oil commonly known as Yellow oleanda (a tropical ornamental
shrub) having about 68.8% unsaturated and 30.9% saturated fatty acids. Urea fractionation
method was used to optimize the percentage of functional groups (in this case double bonds) by
physio-sorption of the saturated fatty acids. The physico-chemical characterization of the optimized
unsaturated FAME such as hydroxyl value, iodine value, saponification value, refractive index,
inherent viscosity were carried out using standard methods. Through condensation reaction the
N,N- bis(2-hydroxyethyl) Thevetia peruviana (HETA) prepared from the FAME react with
isophthalic acid to form polyesteramide. The latter undergo urethanation with H1
•
2 MDI. The
structural elucidation of the moisture cured polyesteramide-urethane urethane coating was based
on FTIR, 1H-NMR and 13C-NMR spectroscopic methods. The coatings films were evaluated for its
antibacterial activity and thermal stability properties on TGA and DSC. SEM of the coating films
was also examine
Anti-microbial and anti-corrosive poly (ester amide urethane) siloxane modified ZnO hybrid coatings from Thevetia peruviana seed oil
The utilization of renewable resources for the
development of organic coatings is a viable means of creating
alternatives to petroleum-based chemicals which are
not eco-friendly. This paper reports the synthesis of polyesteramide–
urethane–silica–zinc oxide hybrid coatings from
Thevetia peruviana seed oil (TPSO). The periphery of ZnO
nano-particles is modified with 3-aminopropyltrimethoxysilane
to prepare silica grafted ZnO composite particles.
The TPSO based polyesteramide was reacted with 4,40-
diisocyanatodicyclohexylmethane in presence of siloxane
modified ZnO to obtain –NCO terminated polyesteramide–
urethane–silica ZnO prepolymer. These hybrid pre-polymers
were casted on tin foil and cured under atmospheric
moisture to obtain eco-friendly, moisture cured polyesteramide–
urethanes–silica–zinc oxide hybrid coating films. The
synthesized polyester and polyurethane formation was confirmed
by using FT-IR and NMR spectroscopic techniques.The resultant hybrid coating films were characterized by
using FT-IR, TGA, DSC, SEM, corrosion resistance and
microbial resistance. Results confirm that with increase of
siloxane modified ZnO content in the polyurethane matrix
thermal stability, glass transition temperature and corrosion
resistance improved. The antibacterial activity shows that
the hybrid films exhibit excellent resistance towards Escherichia
coli and Staphylococcus aureus. The salt spray test
on coated panel samples show good corrosion resistance
properties
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