Possibility of a new order parameter driven by multipolar moment and Fermi surface evolution in CeGe

Polycrystalline CeGe is investigated by means of DC and AC susceptibility, non-linear DC susceptibility, electrical transport and heat capacity measurements in the low temperature regime. This compound shows two peaks at low magnetic field around T^I ~ 10.7 and T^II ~ 7.3 K due to antiferromagnetic ordering and subsequent spin rearrangement respectively. Investigation of non-linear DC susceptibility reveals a presence of higher order magnetization which results in the development of a new order parameter around T^I. This leads to a lowering of symmetry of the magnetic state. The order parameter increases with decreasing temperature and stabilizes around T^II. Consequently, the symmetry of the magnetic state is preserved below this transition. Heat capacity and resistivity results indicate the presence of a gap opening around T^I on portion of Fermi surface, due to evolution of the Fermi surface. Magnetoresistance behavior and violation of Kohler’s rule suggest that the evolution of Fermi surface changes the symmetry of magnetic state. The observation of new order parameter (which is of second order) is also confirmed from the Landau free energy theory.

Assessment of healthcare measures, healthcare resource use, and cost of care among severe hemophilia A patients in Mumbai region of India

Background

In India, the low public health priority given to rare disorders such as hemophilia hinders their management and optimal care, leading to relatively poor health outcomes. This study aims to profile the multidimensional health status of patients with severe hemophilia A, and its association with the use of healthcare resources and the cost of care in Mumbai region of India.

Subjects and Methods

A cross-sectional, single-center study was conducted during January-May 2011, among 160 patients diagnosed with severe hemophilia A in Mumbai region of India. Their health status was documented using the Hemophilia Utilization Group Study's validated instrument of Functional Health Status Measure (FHS) and a single item of Self-care Measure.

Results

Of 160 patients, 55% (n = 88) scored on the lower side on the FHS, with an average score of 6.65 ± 2.85. The use of healthcare resources and cost of treatment were considerable for patients with a lower mean rank score on the FHS and a higher mean rank score on the self-care measure. The consumption of clotting factor concentrates (CFCs), number of visits to a health facility and incidence of inpatient episodes were significantly associated with a relatively low score on the FHS. Similarly, a higher cost of treatment, in terms of the cost of CFCs, direct cost, emergency room cost, and indirect cost, were significantly associated with a lower score on the FHS.

Conclusion

The health status of patients with severe hemophilia A is compromised and has a significant impact on the use of healthcare resources and the cost of treatment.

Cation-specific interactions of protein surface charges in dilute aqueous salt solutions: a combined study using dielectric relaxation spectroscopy and Raman spectroscopy

We exploited glycine as a zwitterionic model system to experimentally probe the cation specific interaction of protein surface charges in dilute (≤0.25 mol L-1) aqueous solutions of four biologically relevant inorganic salts, NaCl, KCl, MgCl2 and CaCl2, via dielectric relaxation spectroscopy (DRS) and Raman spectroscopy. Glycine is the simplest building block of proteins and it exposes the same charged groups (carboxylate and ammonium) to the solvent that dominate the protein-water interface. As a counter ion, we selected Cl- due to its biological importance. For all systems, we performed simultaneous fitting of the real (ε') and imaginary (ε″) parts of the dielectric functions, assuming a multimodal relaxation model, obtained from concentration dependent dielectric measurements at ∼293 K. We observe a reduction of the dielectric amplitude for the glycine relaxation while the corresponding time constant shows only small (<7%) deviations compared to aqueous glycine solutions. We propose that the observed reduction in dielectric amplitude is due to a reduction of the effective dipole moment (µeff) of zwitterionic glycine caused by the interaction of glycine with the ion even at very low (0.05 M) salt concentrations. The interaction between divalent metal ions and zwitterionic glycine is increased compared to the monovalent cation-zwitterion interaction; a finding that is also supported by Raman spectroscopy. Our combined dielectric relaxation and Raman spectroscopic study indicates that ion-glycine interactions are weak and mediated by the solvent. Cation-specificity of protein surface charges is also observed in dilute salt solutions (≤0.25 mol L-1), where electrostatic interactions dominate.

Complex magnetic behaviour and evidence of a superspin glass state in the binary intermetallic compound Er5Pd2

The binary intermetallic compound Er₅Pd₂ has been investigated using dc and ac magnetic susceptibilities, magnetic memory effect, isothermal magnetization, non-linear dc susceptibility, heat capacity and magnetocaloric effect studies. Interestingly, even though the compound does not show geometrical frustration it undergoes glassy magnetic phase transition below 17.2 K. Investigation of dc magnetization and heat capacity data divulged absence of long-ranged magnetic ordering. Through the magnetic memory effect, time dependent magnetization and ac susceptibility studies it was revealed that the compound undergoes glass-like freezing below 17.2 K. Analysis of frequency dependence of this transition temperature through scaling and Arrhenius law; along with the Mydosh parameter indicate, that the dynamics in Er₅Pd₂ are due to the presence of strongly interacting superspins rather than individual spins. This phase transition was further investigated by non-linear dc susceptibility and was characterized by static critical exponents γ and δ. Our results indicate that this compound shows the signature of superspin glass at low temperature. Additionally, both conventional and inverse magnetocaloric effect was observed with a large value of magnetic entropy change and relative cooling power. Our results suggest that Er₅Pd₂ can be classified as a superspin glass system with large magnetocaloric effect.

The Presence of MMP-20 Reinforces Biomimetic Enamel Regrowth

Biomimetic synthesis of artificial enamel is a promising strategy for the prevention and restoration of defective enamel. We have recently reported that a hydrogel system composed of chitosan-amelogenin (CS-AMEL) and calcium phosphate is effective in forming an enamel-like layer that has a seamless interface with natural tooth surfaces. Here, to improve the mechanical system function and to facilitate the biomimetic enamel regrowth, matrix metalloproteinase-20 (MMP-20) was introduced into the CS-AMEL hydrogel. Inspired by our recent finding that MMP-20 prevents protein occlusion inside enamel crystals, we hypothesized that addition of MMP-20 to CS-AMEL hydrogel could reinforce the newly grown layer. Recombinant human MMP-20 was added to the CS-AMEL hydrogel to cleave full-length amelogenin during the growth of enamel-like crystals on an etched enamel surface. The MMP-20 proteolysis of amelogenin was studied, and the morphology, composition, and mechanical properties of the newly grown layer were characterized. We found that amelogenin was gradually degraded by MMP-20 in the presence of chitosan. The newly grown crystals in the sample treated with MMP-20-CS-AMEL hydrogel showed more uniform orientation and greater crystallinity than the samples treated with CS-AMEL hydrogel without MMP-20. Stepwise processing of amelogenin by MMP-20 in the CS-AMEL hydrogel prevented undesirable protein occlusion within the newly formed crystals. As a result, both the modulus and hardness of the repaired enamel were significantly increased (1.8- and 2.4-fold, respectively) by the MMP-20-CS-AMEL hydrogel. Although future work is needed to further incorporate other enamel matrix proteins into the system, this study brings us one step closer to biomimetic enamel regrowth.

Enhancement of magnetic ordering temperature and magnetodielectric coupling by hole doping in a multiferroic DyFe0.5Cr0.5O3

We report the results of our investigation of magnetic, thermodynamic and dielectric properties of Ca substituted half-doped orthochromite, Dy_0.6Ca_0.4Fe_0.5Cr_0.5O₃. Magnetic susceptibility and heat capacity data bring out that this compound undergoes two antiferromagnetic transitions, one at ~132 and the other at ~22 K. These values are higher than those of DyFe_0.5Cr_0.5O₃. This finding highlights that non-magnetic hole doping in form of Ca⁺² in the place of magnetic Dy⁺³ tends to enhance magnetic transition temperatures in this half-doped orthochromite. We attribute it to possible change in the valence state of Cr/Fe-ion ions due to hole doping. Dielectric anomalies are also seen near the magnetic ordering temperatures indicating magnetodielectric coupling, which is confirmed by magnetic field dependent dielectric studies. The most notable observation is that magnetodielectric coupling strength gets significantly enhanced as compared to DyFe_0.5Cr_0.5O₃. The results reveal that it is possible to tune magnetodielectric coupling by hole doping in this system.

Safety assessment of selected medicinal food plants used in Ayurveda through CYP450 enzyme inhibition study

BACKGROUND

Andrographis paniculata, Bacopa monnieri and Centella asiatica are mentioned in Ayurveda for the management of neurodegenerative disorders. These plants and their phytomolecules, such as andrographolide, bacoside A and asiaticoside, were studied for their inhibition potential on pooled CYP450 as well as human CYP3A4, CYP2D6, CYP2C9 and CYP1A2 by CYP-CO complex assay and fluorogenic assay respectively followed by IC₅₀ determination. Quantification of bioactive compounds present in the extracts was done by RP-HPLC. Heavy metal content in the selected medicinal plants was determined by atomic absorption spectroscopy.

RESULT

CYP-CO complex assay indicated significantly less inhibition potential than standard inhibitor (P < 0.05 and above). A. paniculata showed highest inhibitory activity against CYP3A4 and CYP2D6 (IC₅₀ = 63.06 ± 1.35 µg mL^-1 ; 88.80 ± 3.32 µg mL^-1 ), whereas C. asiatica and B. monnieri showed least inhibitory activity against CYP1A2 (IC₅₀ = 288.83 ± 1.61 µg mL^-1 ) and CYP2C9 (184.68 ± 3.79 µg mL^-1 ), respectively. In all cases the extract showed higher inhibition than the single bioactive compounds. The heavy metals content in the plant extracts were within the permissible limits.

CONCLUSION

The findings suggested that selected food plants and bioactive compounds contributed negligible interaction potential with CYP isozymes and may not possess any harmful effect with regard to their therapeutic application. © 2016 Society of Chemical Industry.

Effect of rare-earth (Er and Gd) substitution on the magnetic and multiferroic properties of DyFe0.5Cr0.5O3

We report the results of our investigations on the influence of partial substitution of Er and Gd for Dy on the magnetic and magnetoelectric properties of DyFe0.5Cr0.5O3, which is known to be a multiferroic system. Magnetic susceptibility and heat capacity data, apart from confirming the occurrence of magnetic transitions at ~121 and 13 K in DyFe0.5Cr0.5O3, bring out that the lower transition temperature only is suppressed by rare-earth substitution. Multiferroic behavior is found to persist in Dy0.4Ln0.6Fe0.5Cr0.5O3 (Ln  =  Er and Gd). There is an evidence for magnetoelectric coupling in all these materials with qualitative differences in its behavior as the temperature is changed across these two transitions. Remnant electric polarization is observed for all the compounds. The most notable observation is that electric polarization is seen to get enhanced as a result of rare-earth substitution with respect to that in DyFe0.5Cr0.5O3. Interestingly, a similar trend is seen in the magnetocaloric effect, consistent with the existence of magnetoelectric coupling. The results thus provide evidence for the tuning of magnetoelectric coupling by rare-earth substitution in this family of oxides.

Interaction potential of Trigonella foenum graceum through cytochrome P450 mediated inhibition

Objective:

The seeds of Trigonella foenum-graecum (TFG) (family: Leguminosae) are widely consumed both as a spice in food and Traditional Medicine in India. The present study was undertaken to evaluate the inhibitory effect of standardized extract of TFG and its major constituent trigonelline (TG) on rat liver microsome (RLM) and cytochrome P450 (CYP450) drug metabolizing isozymes (CYP3A4 and CYP2D6), which may indicate the possibility of a probable unwanted interaction.

Materials and Methods:

Reverse phase-high performance liquid chromatography method was developed to standardize the hydroalcoholic seed extract with standard TG. The inhibitory potential of the extract and TG was evaluated on RLM and CYP isozymes using CYP450-carbon monoxide (CYP450-CO) complex assay and fluorescence assay, respectively.

Results:

The content of TG in TFG was found to be 3.38% (w/w). The CYP-CO complex assay showed 23.32% inhibition on RLM. Fluorescence study revealed that the extract and the biomarker had some inhibition on CYP450 isozymes e.g. CYP3A4 and CYP2D6 (IC₅₀ values of the extract: 102.65 ± 2.63–142.23 ± 2.61 µg/ml and TG: 168.73 ± 4.03–180.90 ± 2.49 µg/ml) which was very less compared to positive controls ketoconazole and quinidine. Inhibition potential of TFG was little higher than TG but very less compared to positive controls.

Conclusions:

From the present study, we may conclude that the TFG or TG has very less potential to inhibit the CYP isozymes (CYP3A4, CYP2D6), so administration of this plant extract or its biomarker TG may be safe.

A differently managed Spleen Injury

Introduction: Treatment of symptomatic splenic injury after more than 1 month of the trauma is not very specific. Moreover, here, we are reporting such a case where the patient was treated laparoscopically salvaging the spleen.

Case report: A 26-year-old young male presented with persistent pain in the left upper abdomen and back, following a splenic injury while playing football 1 month ago. Abdominal ultrasound showed subcapsular hematoma with intact hilum. Contrast-enhanced computed tomography of whole abdomen showed large subcapsular hematoma grade III with intact hilar vessels. In view of persistent pain and discomfort, which debilitated and restrained him from daily as well as professional activity, even after 1 month of trauma, the patient was planned for diagnostic laparoscopy and proceed, which revealed hemoperitoneum and was aspirated. Omentum was separated from splenic capsule, breech in the capsule was extended, and hematoma was sucked out. The drain was removed on 4th postoperative day after ultrasound to exclude any fresh hemorrhage. The patient soon started daily activity and resumed his job after 15 days.

Conclusion: Surgical intervention in a hemodynamically stable splenic-injury patient may sometimes be required depending upon the condition and symptoms of the patient.

Zinc oxide thin film based nonenzymatic electrochemical sensor for the detection of trace level catechol

In the present work, a novel zinc oxide thin film based nonenzymatic, electrochemical sensor is developed for the detection of catechol.

Hierarchical zinc oxide nano-tips and micro-rods: hydrothermal synthesis and improved chemi-resistive response towards ethanol

In the present work, a novel hierarchical architecture of zinc oxide has been synthesized through a spherical carbon template assisted two step hydrothermal process.

Visible light absorption and photo-sensitizing properties of spinach leaves and beetroot extracted natural dyes

Herein, chlorophyll and betalain dyes are extracted from fresh spinach leaves and beetroots. Fourier transform infrared spectra are used to identify the characteristic peaks of the extracted dyes. UV-vis light absorption characteristics of the dyes and their mixed counterpart are investigated by varying their pH and temperature. These dyes are used as photo sensitizer for fabrication of zinc oxide photo-anode based dye sensitized solar cells (DSSCs). The photo-voltaic characteristics of the developed DSSCs are measured under simulated solar light (power of incident light 100 mW cm(-2) from Air Mass 1.5G). The solar to electric conversion efficiencies for the chlorophyll, betalain and mixed dye based solar cells are estimated as 0.148%, 0.197% and 0.294% respectively. The highest conversion efficiency for mixed dye based solar cell is attributed due to the absorption of wider range of solar spectrum.

Best Combination of Promoter and Micellar Catalyst for Room Temperature Rapid Conversion of D-Lyxose to D-Lyxonic Acid in Aqueous Medium

The kinetic study of catalytic oxidation of D-lyxose by hexavalent chromium has been investigated spectrophotometrically under pseudo first order condition at temperature 313 K. The rate of oxidation of D-lyxose is very slow. Picolinic acid (PA), 2,2′-bipyridine (bpy), 1,10-phenanthroline (phen) are used as promoter to accelerate the rate of the reaction. Phen acts as the most effective promoter in aqueous medium. The rate of the reaction is also increased in presence of nonionic surfactant Triton-X-100 (TX-100) and anionic surfactant sodium dodecyl sulphate (SDS). They are used as catalyst in this reaction. Thus the observed micellar effects have been explained by considering the hydrophobic and electrostatic interactions between the reactants and surfactants in terms of the proposed mechanism. However, the combination of promoter and surfactants produces a better result. The maximum rate enhancement is obtained in presence of the combination of phen and TX-100.

Surfactant Assisted Enhancement of Bioremediation Rate for Hexavalent Chromium by Water Extract of Siris (Albizia lebbeck) Sawdust

Cr(VI) is introduced into environment as a byproduct of industries. It is highly toxic. Biosorption of hexavalent chromium by various types of sawdust appears as a very cost-effective alternative for decontamination of Cr(VI) bearing effluents. In this work water extract of siris sawdust is used for the bioremediation of hexavalent chromium. Cr(VI) ions were reduced to Cr(III) ions as a result of oxidation of organic components present in the water extract of siris sawdust. Formation of Cr(III) is proved by UV-VIS spectroscopy. Functional groups involved in the reduction of Cr(VI) are characterized by FTIR spectroscopy. Bioremediation rate is increased by the use of anionic surfactant sodium dodecylsulphate (SDS) and neutral surfactant Triton-X-100 (TX-100). Here they act as micellar catalyst. Formation of micelles which is responsible for the catalysis of the process is proved by SEM and optical images of the solution. In absence of surfactants 39 % of the total chromium(VI) is reduced within 531 h whereas removal percentage increases upto 54 % in presence of TX-100. Again in presence of SDS the reduction process is almost 99 % complete within 531 h.

Combination of Best Promoter and Micellar Catalyst for Cr(VI) Oxidation of Lactose to Lactobionic Acid in Aqueous Medium at Room Temperature

In aqueous acidic media, picolinic acid, 2,3-dipicolinic acid, and 2,6-dipicolinic acid promoted Cr(VI) oxidation of lactose to lactobionic acid has been carried out at room temperature. A possible reaction mechanism, which is based on the kinetic results and the product analysis, has been proposed. The anionic surfactant sodium dodecyl sulphate (SDS) and nonionic surfactant Triton-X-100 (TX-100) accelerate the process while the cationic surfactant N-cetylpyridinium chloride (CPC) retards the reaction.

Cytochrome P450 inhibitory potential and RP-HPLC standardization of trikatu--a Rasayana from Indian Ayurveda

ETHNOPHARMACOLOGICAL RELEVANCE

Trikatu is a very well known 'Rasayana' in Ayurveda and widely used as a polyherbal ayurvedic formulation in India. It consists of three well known plants, viz., Piper longum (PL), Piper nigrum (PN) and Zingiber officinale (ZO) in equal ratio. Trikatu has been prescribed for cough, cold, fever, asthma, respiratory problems and improvement of digestive disorders. The aim of the present study was to investigate the effect of individual ingredients of trikatu namely PL, PN, and ZO and formulations [Marketed formulation (MF) and laboratory formulation (LF)] on drug metabolizing enzymes (CYP3A4 and CYP2D6), to assess its herb-drug interaction potential through cytochrome P450 inhibition assays. Further this work was aimed to develop an RP-HPLC method for the identification and quantification of piperine and 6-gingerol in the crude drug trikatu.

MATERIALS AND METHODS

Enzyme inhibition effect of LF, MF, PL, PN and ZO was explored through CYP450-CO complex assay using rat liver microsomes (RLM) and a fluorescence screening method using individual isoenzymes (CYP3A4 and CYP2D6). The RP-HPLC method was developed for the identification and quantification of piperine and 6-gingerol in LF, MF and individual plant materials at the concentration of 1mg/mL.

RESULTS

RP-HPLC analysis confirmed the presence of piperine and 6-gingerol in LF and MF [Piperine: 7.89±2.12% (w/w) (MF), 6.70±2.13% (w/w) (LF)]; [6-gingerol: 5.3±1.21% (w/w) (MF), 4.95±2.34% (w/w) (LF)]. Inhibitory potential of MF and LF in CYP450-CO complex assay was found to be 37.54±3.12% (MF) and 35.12±2.31% (LF) and against CYP2D6 and CYP3A4 was estimated to be IC50 251.30±3.98 and 245.23±1.92μg/mL and IC50 225.50±1.02 and 223.254±0.92μg/mL respectively.

CONCLUSIONS

Different concentrations of the trikatu formulation and its individual components showed significantly (p<0.001) less inhibitory activity on individual isoenzymes as compared to the positive control. The crude drug exhibited inhibitory potential against the CYP450 enzymes in a concentration dependent manner. Outcome of the present study demonstrated that trikatu has less interaction potential with drug metabolizing enzymes.

Identification of RAPD-SCAR marker linked to white spot syndrome virus resistance in populations of giant black tiger shrimp, Penaeus monodon Fabricius

White spot disease (WSD) caused by white spot syndrome virus (WSSV) creates severe epizootics in shrimp aquaculture industry worldwide. Despite several efforts, no such permanent remedy was yet developed. Selective breeding using DNA markers would be a cost-effective strategy for long-term solution of this problem. In the present investigation, out of 30 random primers, only one primer produced a statistically significant (P < 0.01) randomly amplified polymorphic DNA (RAPD) marker of 502 bp, which provided a good discrimination between disease resistant and disease susceptible populations of Penaeus monodon from three geographical locations along the East coast of India. Because RAPD markers are dominant, a sequence characterized amplified region (SCAR) marker was developed by cloning and sequencing of 502 bp RAPD fragment, which generates a single 457 bp DNA fragment after PCR amplification only in the disease resistant shrimps. Challenge experiment was also conducted to validate this 457 bp SCAR marker, and the results suggested that the WSSV loads were 2.25 × 10(3) fold higher in disease susceptible than that in disease resistant shrimps using real-time PCR. Therefore, this 457 bp DNA SCAR marker will be very valuable towards the development of disease-free shrimp aquaculture industry.

Best combination of promoter and micellar catalyst for the rapid conversion of sorbitol to glucose

Kinetic data for oxidation of D-sorbitol to glucose by hexavalent chromium in aqueous medium and aqueous surfactant medium (SDS, TX-100) have been reported. Effect of promoter such as PA, bipy and phenanthroline on the reaction has been investigated. The reaction is performed under pseudo first order condition with an excess of substrate over the oxidant. The reaction is first order with respect to substrate and oxidant. The micelles have a catalytic effect on the reaction. Combination of phen and TX-100 produces almost twelve times increase in rate of oxidation.