218 research outputs found
Anti-inflammatory and analgesic activity of different fractions of Boswellia serrata
The study was designed to investigate the anti-inflammatory and analgesic effect of different fractions of Boswellia serrata. The effect of different fractions of Boswellia serrata were studied using carrageenan induced paw edema, acetic acid induced writhing response, formalin induced pain, hot plate and tail flick method for studying anti-inflammatory and analgesic activity, respectively. The different fractions of B. serrata, essential oil (10 ml/kg), gum (100 mg/kg, resin (100 mg/kg) oleo-resin (100 mg/kg) and oleo-gum-resin (100 mg/kg) significantly reduces carrageenan induced inflammation in rats and shows analgesic activity, as determined by acetic acid induced writhing response, formalin induced pain, hot plate and tail flick method. The different fractions of B. serrata showed prompt anti-inflammatory and analgesic activity due to the inhibition of 5-lipoxygenase enzyme.Keywords: Analgesic; Boswellia serrata; Inflammation; 5- lipoxygenase; Burseraceae
Comparative Evaluation of ICP-AES and Turbidimetric Methods for Determining Extractable Sulfur in Soils
The deficiency of sulfur (S) as a constraint to crop productivity in irrigated, intensified systems has long been recognized (Kanwar 1972; Pasricha and Fox 1993; Singh 2001). A recent survey of farmers’ fields in the Indian semi-arid tropics (SAT) demonstrated that the deficiency of S, as a constraint to crop production and productivity, is also equally widespread in the rainfed production systems (Rego et al. 2007; Sahrawat et al. 2007). The results of this research further showed that soil testing was effective in diagnosing S deficiency; and the crops grown on farmers’
fields with calcium chloride extractable-S levels of less than 8-10 mg kg-1 soil responded positively to the application of sulfur (Rego et al. 2007)
Paramagnetic GaN:Fe and ferromagnetic (Ga,Fe)N - relation between structural, electronic, and magnetic properties
We report on the metalorganic chemical vapor deposition (MOCVD) of GaN:Fe and
(Ga,Fe)N layers on c-sapphire substrates and their thorough characterization
via high-resolution x-ray diffraction (HRXRD), transmission electron microscopy
(TEM), spatially-resolved energy dispersive X-ray spectroscopy (EDS),
secondary-ion mass spectroscopy (SIMS), photoluminescence (PL), Hall-effect,
electron-paramagnetic resonance (EPR), and magnetometry employing a
superconducting quantum interference device (SQUID). A combination of TEM and
EDS reveals the presence of coherent nanocrystals presumably FexN with the
composition and lattice parameter imposed by the host. From both TEM and SIMS
studies, it is stated that the density of nanocrystals and, thus the Fe
concentration increases towards the surface. In layers with iron content x<0.4%
the presence of ferromagnetic signatures, such as magnetization hysteresis and
spontaneous magnetization, have been detected. We link the presence of
ferromagnetic signatures to the formation of Fe-rich nanocrystals, as evidenced
by TEM and EDS studies. This interpretation is supported by magnetization
measurements after cooling in- and without an external magnetic field, pointing
to superparamagnetic properties of the system. It is argued that the high
temperature ferromagnetic response due to spinodal decomposition into regions
with small and large concentration of the magnetic component is a generic
property of diluted magnetic semiconductors and diluted magnetic oxides showing
high apparent Curie temperature.Comment: 21 pages, 30 figures, submitted to Phys. Rev.
Comparative Evaluation of Inductively Coupled Plasma–Atomic Emission Spectroscopy and Colorimetric Methods for Determining Hot-Water-Extractable Boron in Soils
Frequency of boron (B) deficiency is increasing in rainfed systems, and hence there is a need to diagnose the deficiency. Colorimetric methods are still widely used in soil-testing laboratories in India for measuring B. Little information is available on the comparative evaluation of the colorimetric and inductively coupled plasma (ICP) methods for determining extractable B in soils. We describe results of the comparative evaluation of these methods for measuring extractable B in 57 soil samples with pH values ranging from 5.3 to 9.5. There was a significant correlation between B values determined by the two methods, and the correlation coefficient was greater for soil samples with pH in the neutral to alkaline range. Interaction between soil samples and methods (ICP or colorimetric) was significant except for soil samples in the pH range of 8.0 to 9.5. Precision for B determination was greater with the ICP than with the colorimetric method
Surfactant protein D inhibits HIV-1 infection of target cells via interference with gp120-CD4 interaction and modulates pro-inflammatory cytokine production
© 2014 Pandit et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.Surfactant Protein SP-D, a member of the collectin family, is a pattern recognition protein, secreted by mucosal epithelial cells and has an important role in innate immunity against various pathogens. In this study, we confirm that native human SP-D and a recombinant fragment of human SP-D (rhSP-D) bind to gp120 of HIV-1 and significantly inhibit viral replication in vitro in a calcium and dose-dependent manner. We show, for the first time, that SP-D and rhSP-D act as potent inhibitors of HIV-1 entry in to target cells and block the interaction between CD4 and gp120 in a dose-dependent manner. The rhSP-D-mediated inhibition of viral replication was examined using three clinical isolates of HIV-1 and three target cells: Jurkat T cells, U937 monocytic cells and PBMCs. HIV-1 induced cytokine storm in the three target cells was significantly suppressed by rhSP-D. Phosphorylation of key kinases p38, Erk1/2 and AKT, which contribute to HIV-1 induced immune activation, was significantly reduced in vitro in the presence of rhSP-D. Notably, anti-HIV-1 activity of rhSP-D was retained in the presence of biological fluids such as cervico-vaginal lavage and seminal plasma. Our study illustrates the multi-faceted role of human SPD against HIV-1 and potential of rhSP-D for immunotherapy to inhibit viral entry and immune activation in acute HIV infection. © 2014 Pandit et al.The work (Project no. 2011-16850) was supported by Medical Innovation Fund of Indian Council of Medical Research, New Delhi, India (www.icmr.nic.in/)
Effect of silver nanoparticles on the physicochemical and antimicrobial properties of an orthodontic adhesive
ABSTRACT Orthodontic treatment with fixed brackets plays a major role on the formation of white spot lesions. Objective This study aimed to incorporate silver nanoparticle solutions (AgNP) in an orthodontic adhesive and evaluate its physicochemical and antimicrobial properties. Material and Methods Silver nanoparticle solutions were added to a commercial adhesive in different concentrations (w/w): 0%, 0.11%, 0.18%, and 0.33%. Shear bond strength (SBS) test was performed after bonding metal brackets to enamel. Raman spectroscopy was used to analyze in situ the degree of conversion (DC) of the adhesive layer. The surface free energy (SFE) was evaluated after the measurement of contact angles. Growth inhibition of Streptococcus mutans in liquid and solid media was determined by colony-forming unit count and inhibition halo, respectively. One-way ANOVA was performed for SBS, DC, SFE, and growth inhibition. Results The incorporation of AgNP solution decreased the SBS (p<0.001) and DC in situ (p<0.001) values. SFE decreased after addition of 0.18% and 0.33% AgNP. Growth inhibition of S. mutans in liquid media was obtained after silver addition (p<0.05). Conclusions The addition of AgNP solutions to Transbond™ XT adhesive primer inhibited S. mutans growth. SBS, DC, and SFE values decreased after incorporation up to 0.33% AgNP solution without compromising the chemical and physical properties of the adhesive
Hydrocarbon Contamination Decreases Mating Success in a Marine Planktonic Copepod
The mating behavior and the mating success of copepods rely on chemoreception to locate and track a sexual partner. However, the potential impact of the water-soluble fraction of hydrocarbons on these aspects of copepod reproduction has never been tested despite the widely acknowledged acute chemosensory abilities of copepods. I examined whether three concentrations of the water-soluble fraction of diesel oil (0.01%, 0.1% and 1%) impacts (i) the swimming behavior of both adult males and females of the widespread calanoid copepod Temora longcornis, and (ii) the ability of males to locate, track and mate with females. The three concentrations of the water-soluble fraction of diesel oil (WSF) significantly and non-significantly affect female and male swimming velocities, respectively. In contrast, both the complexity of male and female swimming paths significantly decreased with increasing WSF concentrations, hence suggesting a sex-specific sensitivity to WSF contaminated seawater. In addition, the three WSF concentrations impacted both T. longicornis mating behavior and mating success. Specifically, the ability of males to detect female pheromone trails, to accurately follow trails and to successfully track a female significantly decreased with increasing WSF concentrations. This led to a significant decrease in contact and capture rates from control to WSF contaminated seawater. These results indicate that hydrocarbon contamination of seawater decreases the ability of male copepods to detect and track a female, hence suggest an overall impact on population fitness and dynamics
Structure Activity Relationship of Dendrimer Microbicides with Dual Action Antiviral Activity
Topical microbicides, used by women to prevent the transmission of HIV and other sexually transmitted infections are urgently required. Dendrimers are highly branched nanoparticles being developed as microbicides. However, the anti-HIV and HSV structure-activity relationship of dendrimers comprising benzyhydryl amide cores and lysine branches, and a comprehensive analysis of their broad-spectrum anti-HIV activity and mechanism of action have not been published.Dendrimers with optimized activity against HIV-1 and HSV-2 were identified with respect to the number of lysine branches (generations) and surface groups. Antiviral activity was determined in cell culture assays. Time-of-addition assays were performed to determine dendrimer mechanism of action. In vivo toxicity and HSV-2 inhibitory activity were evaluated in the mouse HSV-2 susceptibility model. Surface groups imparting the most potent inhibitory activity against HIV-1 and HSV-2 were naphthalene disulfonic acid (DNAA) and 3,5-disulfobenzoic acid exhibiting the greatest anionic charge and hydrophobicity of the seven surface groups tested. Their anti-HIV-1 activity did not appreciably increase beyond a second-generation dendrimer while dendrimers larger than two generations were required for potent anti-HSV-2 activity. Second (SPL7115) and fourth generation (SPL7013) DNAA dendrimers demonstrated broad-spectrum anti-HIV activity. However, SPL7013 was more active against HSV and blocking HIV-1 envelope mediated cell-to-cell fusion. SPL7013 and SPL7115 inhibited viral entry with similar potency against CXCR4-(X4) and CCR5-using (R5) HIV-1 strains. SPL7013 was not toxic and provided at least 12 h protection against HSV-2 in the mouse vagina.Dendrimers can be engineered with optimized potency against HIV and HSV representing a unique platform for the controlled synthesis of chemically defined multivalent agents as viral entry inhibitors. SPL7013 is formulated as VivaGel(R) and is currently in clinical development to provide protection against HIV and HSV. SPL7013 could also be combined with other microbicides
Electronic, Mössbauer and magnetic studies of self-assembled monodispersed FePt nanoparticles
805-809The organic ligand encapsulated and bare 4 nm FePt particles, synthesized by wet chemical processing are studied for their structural, electronic and magnetic properties. The fcc phase is stable even above 833 K without any agglomeration and particle growth. The Mössbauer spectra recorded at 10 K for the as-prepared and annealed FePt nanoparticles reveal the presence of superparamagnetic and ferromagnetic fractions. The superparamagnetic blocking temperature decreases from
55 K to 10 K, after annealing at 623 K, due to the decrease in magnetocrystalline anisotropy and Fe-Pt-C is formed at the surface at elevated temperatures. Two distinct sextets are observed at 10 K with a large magnetic hyperfine field for one of the components. The 2D array of the nanoparticles and also the electronic and magnetic properties of the Fe sites are retained even after removing the organic ligand molecules
Mössbauer and magnetic studies for the coexistence of Ɛ-Fe₃₋xNixN and ϒ'-Fe₄₋yNiyN phases in Fe-Ni-N nanoparticles
834-838Nanocrystalline Ɛ-Fe3-xNixN (x = 0.5-0.8) particles are synthesized by precursor technique and nitridation of decomposed products in NH₃ (g) at 673 K. A small fraction of fcc ϒ'-Fe₄₋yNiyN phase (space group: P43m) is precipitated along with the formation of Ɛ-Fe₃₋xNixN hexagonal structure (space group: P63/mmc). The Mössbauer spectrum at room temperature for all the compositions shows the presence of superparamagnetic doublet, which is attributed to Ɛ-Fe₃₋xNixN phase and two sextets corresponding to the corner Fe (Fec) and fcc Fe (Fef), in ϒ'-Fe₄₋yNiyN. The added Ni atoms preferentially substitute the Fec positions. The isomer shift, quadrupole splitting and hyperfine field values vary with the Ni content. The zero-field cooled (ZFC) and field-cooled (FC) curves indicate strong interparticle interactions and surface spin-glass-like state is realized from the low temperature features. The magnetization curves are saturated at 5 K, due to the dominating ferromagnetic nature of the ϒ'-Fe₄₋yNiyN phase
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