240 research outputs found
SYNTHESIS, CHARACTERIZATION, QUANTITATIVE STRUCTURE-ACTIVITY RELATIONSHIP, DOCKING, ANTIBACTERIAL ACTIVITY, AND BRINE SHRIMP LETHAL STUDIES ON L-PHENYLALANINE SCHIFF BASES
ABSTRACTObjective: Aim of this work is to synthesize and characterization of the hydroxyl group the hydroxyl group substituted L-phenylalanine Schiff basesto compare their predicted quantitative structure-activity relationship (QSAR) and molecular docking against Escherichia coli protein ZipA (1s1j)outcomes with the antibacterial activity and brine shrimp lethal assay (BSLA) results.Methods: The Schiff bases of L-Phenylalanine were synthesized by the simple condensation reaction using methanol, water in 2:1 ratio at reflux andwere characterized by spectral techniques. QSAR parameters of the Schiff bases were predicted using java-based online and offline tools. Moleculardocking carried through online mcule server and CLC Drug Discovery Workbench 3. Antibacterial activity and toxicity studies were conducted usingbroth dilution and brine shrimp lethal assay methods, respectively.Results: The Schiff bases fulfilled the QSAR drug-likeness parameters and showed the docking score between −6.8 and −6.0 Kcal/mol which arehigher than amoxilicillin and gentamicin like standard drugs. They also possess good inhibition for urinary tract infection causing E. coli bacteria,and minimum inhibitory concentrations (MIC) exists between 3.25 and 5.25 μg/ml. The brine shrimp lethal concentration for 50% mortality [LC50])between 58.73 and 135.6 μg/ml.Conclusion: Para, meta and 2,4 hydroxyl substituted Schiff bases exhibited good inhibition against Gram-negative E. coli bacteria at low concentrationand the MIC exists below the LC50 value. The Schiff base showed high drug score, high docking score, and low toxicity than other Schiff base. Dockingscore, high inhibition, low clogP, low MICKeywords: L-phenylalanine, Schiff base, Quantitative structure-activity relationship, Docking, Antibacterial, Lethal concentration for 50% mortality
A comparative study on safety and efficacy of travoprost and brimonidine/timolol fixed combination in patients of primary open angle glaucoma
Background: The purpose of this study was to compare and evaluate the clinical efficacy of topically applied travoprost 0.004% eye drops versus brimonidine/timolol fixed combination eye drops in the management of primary open-angle glaucoma.Methods: In this prospective, randomized study, 65 patients received either travoprost eye drops once daily in the morning (n=33) or brimonidine/timolol fixed combination eye drops twice daily (n=32). Intra ocular pressure (IOP) was assessed at 2, 4, 8, and 12 weeks. The primary outcome measure was mean reduction in IOP.Results: Thebaseline mean IOP values were similar between two groups. Mean reduction of IOP in the right eye for brimonidine/timolol fixed combination group was 9±2.9 mmHg, whereas in the left eye it was 10.9±2.8 mmHg. In the travoprost group, the reduction in IOP of the right eye was 7.8±2.9 mmHg (p=0.0002) and 7.5±3.4 mmHg (p=0.0001) in the left eye. The mean reduction of IOP for the brimonidine/timolol group was 9.95 mmHg and for the travoprost group it was 7.6 mmHg (p<0.0001) in both the eyes.Conclusions: The fixed combination brimonidine/timolol twice daily demonstrated superior mean IOP lowering efficacy compared to travoprost 0.004% in patients with open-angle glaucoma
Integrated results from the COPERNICUS and GALILEO studies.
OBJECTIVES: To report on the efficacy and safety of intravitreal aflibercept in patients with macular edema secondary to central retinal vein occlusion (CRVO) in an integrated analysis of COPERNICUS and GALILEO.
PATIENTS AND METHODS: Patients were randomized to receive intravitreal aflibercept 2 mg every 4 weeks or sham injections until week 24. From week 24 to week 52, all intravitreal aflibercept-treated patients in both studies and sham-treated patients in COPERNICUS were eligible to receive intravitreal aflibercept based on prespecified criteria. In GALILEO, sham-treated patients continued to receive sham treatment through week 52.
RESULTS: At week 24, mean gain in best-corrected visual acuity and mean reduction in central retinal thickness were greater for intravitreal aflibercept-treated patients compared with sham, consistent with individual trial results. At week 52, after 6 months of intravitreal aflibercept as-needed treatment in COPERNICUS, patients originally randomized to sham group experienced visual and anatomic improvements but did not improve to the extent of those initially treated with intravitreal aflibercept, while the sham group in GALILEO did not improve over week 24 mean best-corrected visual acuity scores. Ocular serious adverse events occurred in
CONCLUSION: This analysis of integrated data from COPERNICUS and GALILEO confirmed that intravitreal aflibercept is an effective treatment for macular edema following CRVO
Quasiparticle bandgap engineering of graphene and graphone on hexagonal boron nitride substrate
Graphene holds great promise for post-silicon electronics, however, it faces
two main challenges: opening up a bandgap and finding a suitable substrate
material. In principle, graphene on hexagonal boron nitride (hBN) substrate
provides potential system to overcome these challenges. Recent theoretical and
experimental studies have provided conflicting results: while theoretical
studies suggested a possibility of a finite bandgap of graphene on hBN, recent
experimental studies find no bandgap. Using the first-principles density
functional method and the many-body perturbation theory, we have studied
graphene on hBN substrate. A Bernal stacked graphene on hBN has a bandgap on
the order of 0.1 eV, which disappears when graphene is misaligned with respect
to hBN. The latter is the likely scenario in realistic devices. In contrast, if
graphene supported on hBN is hydrogenated, the resulting system (graphone)
exhibits bandgaps larger than 2.5 eV. While the bandgap opening in graphene/hBN
is due to symmetry breaking and is vulnerable to slight perturbation such as
misalignment, the graphone bandgap is due to chemical functionalization and is
robust in the presence of misalignment. The bandgap of graphone reduces by
about 1 eV when it is supported on hBN due to the polarization effects at the
graphone/hBN interface. The band offsets at graphone/hBN interface indicate
that hBN can be used not only as a substrate but also as a dielectric in the
field effect devices employing graphone as a channel material. Our study could
open up new way of bandgap engineering in graphene based nanostructures.Comment: 8 pages, 4 figures; Nano Letters, Publication Date (Web): Oct. 25
2011, http://pubs.acs.org/doi/abs/10.1021/nl202725
Erosion of trust in humanitarian agencies: what strategies might help?
Aid agencies (AAs) provide a range of humanitarian and health related assistance globally. However, the trust placed on them is eroding. Evidence for this includes accusations of a decline in their humanitarianism, and the increasing number of conflicts with host states. An analysis of the concerns expressed yields two possible reasons: a relative lack of transparency of their work and weak accountability mechanisms. This is further supported by the existing milieu: an absence of internationally accepted instrument or mechanism to check the credentials of INGOs and an opaque system of close links between some of the INGOs and their donors. The article suggests two global strategies to tackle these issues: (a) Increase transparency by establishing a global register of aid agencies. This should have basic information: their main goals and activities, countries they are active in, number of employees, annual turnover of funds (updated regularly), principal financing sources and nature of links with donors. This could also be available as printed manual that should be freely available to client countries. (b) Ensure accountability by developing templates of fair legal instruments (to facilitate and regulate work), and a set of generic rules and procedures of engagement for the interactions between agencies and client states. These should be institutionalized within the regulatory frameworks of countries and included in the Codes of Conduct of NGOs
A Study on the Effect of Peristalsis and Cilia of MHD Micropolar Fluid Flow through an Inclined Porous Channel
The study of the influence of magnetic field, channel inclination, porous medium and cilia on the Micropolar fluid under different boundary conditions is carried out. The methods of solving Navier Stokes equation specific to Micropolar fluid under the joint influence of these effects are presented. The profiles of velocity (along the flow direction), the micro rotation vector and the variation of pressure rise with time average flow rate for fixed values of other parameters were carried out and the results are discussed
Impact of Baseline Retinal Nonperfusion and Macular Retinal Capillary Nonperfusion on Outcomes in the COPERNICUS and GALILEO Studies
To evaluate the impact of baseline retinal capillary nonperfusion (RNP) and macular retinal capillary nonperfusion (MNP) status on outcomes at week 24 (W24)
Early Evidence of Cardiotoxicity and Tumor Response in Patients with Sarcomas after High Cumulative Dose Doxorubicin Given as a Continuous Infusion
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