SPECTROPHOTOMETRIC DETERMINATION OF ATORVASTATIN CALCIUM AND PITAVASTATIN CALCIUM THROUGH ION-PAIR COMPLEX FORMATION USING ACID DYES IN PHARMACEUTICAL FORMULATIONS AND HUMAN URINE SAMPLES

Objective: The main objective was to develop simple, cost-effective, rapid and selective spectrophotometric methods for the determination of atorvastatin calcium and pitavastatin calcium in pure and pharmaceutical formulations using acid dyes like bromothymol blue, bromocresol purple and bromocresol green and also in human urine samples. Methods: The developed methods were based on the formation of ion-pair complexes between statin drugs and acid dyes after studying the optimization conditions. The association constants of the developed ion-pair complexes were evaluated using Benesi–Hildebrand equation. The methods were validated according to ICH guidelines. Results: The formed ion-pair complexes showed maximum absorbance which was measured at 637 nm for both methods A and D, 601 nm, 606 nm for methods B and E and 631 nm for both methods C and F respectively with correlation coefficients 0.999. The analytical parameters and their effects in the developed methods were investigated. The ion-pair complexes were stable up to 24 h and showed good linearity. The molar absorptivity, Sandell sensitivity, detection, and quantification limits were also calculated. The stoichiometry ratio in all the cases was 1:2 by using Job’s method of continuous variation. The recovery studies again showed good results because co-formulated substances did not interfere for the determination of ATC and PTC in the developed methods. Conclusion: The developed methods were applicable for routine quality control analysis of ATC and PTC in pure and pharmaceutical dosage forms. Good results were obtained when the developed methods were applied in healthy human urine samples

Misoprostol for cervical ripening at and near term - a comparative study

Objective. To compare the safety and efficacy of misoprostol with that of dinoprostone for the induction of labour at term, or near term.Design. Three hundred and ninety-six women with term pregnancies were randomised to receive either oral or vaginal misoprostol, or dinoprostone. Women who had had a previous caesarean section (CS) or those with a malpresentation or who were parity ≥ 5, were excluded. The control group received dinoprostone 1 mg inserted in the posterior fornix and repeated 6-hourly to a maximum of three doses. The study group received either oral misoprostol 20 pμ 2-hourly to a maximum of four doses (80 μg), or vaginal misoprostol 25 μg in the posterior fornix with a switch to the oral misoprostol regimen if there was no change in the Bishop's score or no palpable uterine contractions.Results. There was no significant difference in vaginal delivery rate within 24 hours between the groups (58.1% v. 58%, p = 0.633). There were no significant differences in CS rates between the groups; however, more CSs were performed for fetal distress in the misoprostol group than in the dinoprostone group (28% v. 25%). There was a significantly higher incidence of hyperstimulation in the vaginal misoprostol group (21.4%) than in the other two groups (oral misoprostol 16.5%, dinoprostone 8.9%) (p = 0.004). The incidence of meconium staining of liquor was comparable between the groups.Conclusions. In selected women, the efficacy of misoprostol for the induction of labour at term is similar to that of dinoprostone but misoprostol is associated with a higher incidence of hyperstimulation

Studies of vitamin A deficiency in children

The clinical features of 319 children with vitamin A deficiency observed in Coonoor and forty-nine children studied in Hyderabad have been discussed in detail. Estimations of the contents of vitamin A and carotene in the serum and the in vitro destruction of vitamin A by lysed red blood cells were carried out. There was a lack of association between the incidence of night blindness and other ocular signs of vitamin A deficiency. Although signs of vitamin A deficiency were always associated with a low dietary intake of carotene and vitamin A, the reverse did not always occur. The proportion of patients with vitamin A deficiency who had keratomalacia was much greater in Hyderabad than in Coonoor. Levels of vitamin A and carotene in the serum were low in all children with vitamin A deficiency. Levels of vitamin A in the serum of subjects with kwashiorkor but without clinical signs of vitamin A deficiency were also found to be significantly lower than the levels in apparently normal children. Treatment with a high protein diet without vitamin A supplementation brought about a significant increase in the levels of vitamin A in the serum in the latter. The in vitro destruction of vitamin A by lysed red blood cells of children suffering from vitamin A deficiency appeared to be higher than that of the normal controls Treatment with vitamin A lowered this abnormal in vitro destruction

Role of chromodomain helicase DNA-binding protein 2 in DNA damage response signaling and tumorigenesis.

The chromodomain helicase DNA-binding proteins (CHDs) are known to affect transcription through their ability to remodel chromatin and modulate histone deacetylation. In an effort to understand the functional role of the CHD2 in mammals, we have generated a Chd2 mutant mouse model. Remarkably, the Chd2 protein appears to play a critical role in the development, hematopoiesis and tumor suppression. The Chd2 heterozygous mutant mice exhibit increased extramedullary hematopoiesis and susceptibility to lymphomas. At the cellular level, Chd2 mutants are defective in hematopoietic stem cell differentiation, accumulate higher levels of the chromatin-associated DNA damage response mediator, cH2AX, and exhibit an aberrant DNA damage response after X-ray irradiation. Our data suggest a direct role for the chromatin remodeling protein in DNA damage signaling and genome stability maintenance

First principles studies of the potential-induced lifting of the Au(100) surface reconstruction

The potential-induced surface reconstruction of Au(100) has been studied by a combination of density functional theory and thermodynamic considerations. Surface free energies of reconstructed-(5 x 1) and unreconstructed-(1 x 1) surfaces were calculated as function of an external electric field using the extended ab initio atomistic thermodynamics approach. After relating electric field and electrode potential by using capacitance measurements, we calculate lifting of the reconstruction to occur at 0.58 V in 0.01 M HClO4 and 0.27 V in 0.01 M H2SO4, being in agreement with the experimental values of 0.60 and 0.27 V (vs. SCE). Finally, the consequences of using experimental capacitance measurements for calculating surface free energies are discussed

Spectroscopic and quantum mechanical investigations of (2E)-3-(2H-1,3-benzodioxol-5-yl)-N-phenylprop-2-enamide using density functional theory method

The Fourier transform infrared (FTIR) and FT-Raman of (2E)-3-(2H-1,3-benzodioxol-5-yl)-N-phenylprop-2-enamide (2BNP2E) have been recorded in the regions 4000-100 and 4000-450cm-1, respectively. A complete assignment and analysis of the fundamental vibrational modes of the molecule have been carried out. The observed fundamental modes have been compared with the harmonic vibrational frequencies computed using DFT (B3LYP) method by employing 6-311++G(d,p) basis set. The vibrational studies have been interpreted in terms of potential energy distribution. The first order hyperpolarizability (β0) and related properties (α, μ and ∆α) of this molecular system are calculated using B3LYP/6-311++G(d,p) method based on the finite-field approach. Stability of the molecule arising from hyperconjugative interactions and charge delocalization has been analyzed using natural bond orbital (NBO) analysis. The results show that electron density (ED) in the σ* and π* anti-bonding orbitals and second-order delocalization energies (E(2)) confirm the occurrence of intramolecular charge transfer (ICT) within the molecule. Molecular electrostatic potential (MEP) and HOMO-LUMO energy levels have also been constructed. The thermodynamic properties of the title compound have been calculated at different temperature and the results reveal that the standard heat capacity C, entropy S and enthalpy changes H increase with rise in temperature

Post-harvest soil nutrient prediction in hybrid castor (Ricinus communis l.) Cropping sequence using a multivariate analysis technique

In the era of precision agriculture, the fertilizer prescription based on the soil fertility status is much required.  Analyzing the soil after each crop is necessary for fertilizer recommendation and developing an alternative technique to forecast the soil available nutrient value rather than analyzing the soil. Multiple linear regression (MLR) equation was developed using filed experiment data to predict the soil available nutrient in castor cropping sequence. The post-harvest soil available nutrient was considered as the dependent variable and the initially available soil nutrient values, fertilizer added, yield and nutrient uptake of castor as an independent variable. In general, the post-harvest soil nutrient model's prediction accuracy was notable and had a coefficient of determination of less than 0.90. By calculating the RMSE (root means square error), R2 value, the ratio performance to deviation (RPD) and, RE (relative error) the performance of the MLR model was confirmed.Using the validated model, post-harvest soil available nutrients were predicted and compared with laboratory tested soil available nutreints. It turned out that the established model is more precisely effective and equally precise. Fertilizer recommendation could be made to subsequent crop after hybrid castor using the predicted soil available nutrients