166 research outputs found
2D and 3D QSAR studies and antibacterial activity of 4-methyl-3-(6-{[arylmethylene] amino}pyridin-3-YL)-2H-chromen-2-one derivatives
4-methyl-3-(6-{[arylmethylene] amino} pyridin-3-yl)-2H-chromen-2-one derivatives containing different functional groups have been synthesized and screened for their antibacterial activity against four different strains of bacteria. 2D and 3D QSAR analysis of synthesized derivatives were performed on Vlife MDS 3.5 software. The data set for QSAR studies encompassed activities of 64 molecules divided into training and test set. The best models were selected on basis of correlation coefficient (r2) and internal and external predictivity (Pred_r2) of the QSAR model. QSAR models reveled that electronic, steric and liphophillic parameters have correlation with antibacterial activity. The 3D interactions and their contributions indicate multi-targeted mode of action of the compounds.Colegio de Farmacéuticos de la Provincia de Buenos Aire
Evaluation of functional outcome after osteosynthesis of intra articular distal humerus fracture with pre contoured locking compression plates
Background: Intra articular distal humerus fractures are challenging and cumbersome to treat. Therefore osteosynthesis of such fractures is required. The aim of our study was to evaluate the functional outcome of intra articular distal humerus fractures AO type 13C by osteosynthesis using olecranon osteotomy with pre contoured locking compression plates in orthogonal plate configuration.Methods: Thirty patients were included in our study comprising of 18 males and 12 females. Mean age was 39.63 years with mean follow up of 34 weeks. 7 were AO type 13C1, 9 were AO type 13C2 and 14 were AO type 13C3. Osteosynthesis was done for all fractures by olecranon osteotomy approach. Functional outcome was assessed using mayo elbow performance score.Results: Mean flexion attained at the end of follow up was 127.56 degrees with mean extensor lag of 7.16 degrees. Mean arc of motion was 120.4 degrees. Mean mayo elbow performance score at the end of follow up was 80.36. Mayo elbow performance score in patients aged less than 40 years of age was not statistically significant as compared to patients more than 40 years of age. Functional outcome was also dependent on fracture subtype.Conclusions: Osteosynthesis of distal humerus fractures AO type 13C using pre contoured locking compression plates in orthogonal plate configuration by olecranon osteotomy provides excellent visualization of fracture and better functional outcome
DEVELOPMENT AND VALIDATION OF SPECTROPHOTOMETRIC AND ION PAIR CHROMATOGRAPHIC TECHNIQUE FOR ESTIMATION OF VALSARTAN AND HYDROCHLOROTHIAZIDE
Two new simple, sensitive, rapid, accurate and reproducible methods (UV-spectrophotometric and ion pair chromatography) have been developed for simultaneous estimation of valsartan (VAL) and hydrochlrothiazide (HCTZ) from their tablet dosage form. The first method involves multiwavelength spectrophotometric method (Method 1) in which interference of HCTZ at 245nm (wavelength for estimation of VAL) was removed by recording absorbance difference at 245nm and 301 nm whereas HCTZ was estimated directly from its absorbance at 316 nm at which VAL shows no absorbance. Linearity of the response was demonstrated by VAL in the concentration range of 5-45 g/ml with a square correlation coefficient (r2) of 0.9998. Linearity of the response was demonstrated by HCTZ in the concentration range of 2-18 g/ml with a square correlation coefficient (r2) of 0.9994. The second method utilizes ion pair chromatography (Method 2) on a HIQ sil ODS column (250 mm* 4.6 mm i.d.) using methanol: 0.0025 M orthophosphoric acid: (70:30 by volume) having pH 4.6: 0.1% hexane sulphonic acid as mobile phase with UV detection at 259nm over concentration range for VAL is 240-0 μg/ml, and for HCTZ is 75-0μg/ml. Losartan potassium was used as the internal standard. The suggested procedures were checked using laboratory prepared mixtures and were applied successfully for the analysis of their tablet dosage form. The results of analysis were statistically analysed. Both the methods were validated as per ICH Q2B guideline
Comparative Studies of Photochemical and Electrochemical Methods on Mineralization of Picric Acid
The effluents generated from synthesis and processing plant of Picric acid is reported to be carcinogenic and hence needs to be treated to reduce its concentration below safe discharge limit. Present paper deals with studies on mineralization of Picric acid by adopting photochemical and electrochemical processes and the efficacy of the both processes have been explored in details. Crucial process parameters viz. pH, concentration of oxidizer and catalyst for mineralization of Picric acid are optimized. In photochemical method, It is observed that Picric acid is treated to bring down its concentration from 100 ppm to ≤ 1 ppm under Photo-Fenton process in 2 hrs whereas same treatment carried out under Photo- catalytic process takes only 1 hr. It is also observed that TiO2 xerogel and beads of nano-TiO2 are more efficient compared to that of commercially available TiO2. The TiO2–Polysulfone (PS) beads show less efficiency than TiO2 xerogel. However, the Picric acid oxidation efficiency for TiO2–PS beads is comparable and advantage of TiO2–PS beads is that it can easily be recovered from the treated solution and can be reused in the next experiments. Electrochemical process is user’s friendly and economical. In case of electrochemical treatments at optimized process parameters under Electro-Fenton reaction picric acid is completely mineralized below its drain discharge limit where as under Electro-peroxide reaction picric acid is mineralized upto 3 ppm within 3 hrs. The treated solution has been characterized by using UV-Visible spectrophotometer, High performance Liquid Chromatography (HPLC) and Total Organic Carbon (TOC) Analyzer. The observed results have been interpreted and reported in the present paper
Synthesis, Characterization and Quantification of Simvastatin Metabolites and Impurities
Simvastatin is used in treatment of hypercholesterolemia because it regulates cholesterol synthesis as a result of its β-hydroxy acid acting as an inhibitor of 3-hydroxy-methylglutaryl coenzyme A (HMG-CoA). The present communication deals with synthesis, characterization and development of accurate, precise and sensitive Reverse Phase High Performance Liquid Chromatography (RP-HPLC) method for simultaneous estimation of simvastatin and its synthetic impurities. The impurities methyl ether and β-hydroxy acid of simvastatin were synthesized in the laboratory and characterized by MS, NMR and FT-IR spectroscopy. The separation of simvastatin and its impurities was carried out on an isocratic JASCO RP-HPLC system using KYA TECH HIQ SIL C18 column (150 × 4.6 mm internal diameter, particle size 5 μm) operating at ambient temperature using acetonitrile:water (80:20 v/v) with 0.1% orthophosphoric acid as mobile phase. The method developed for HPLC analysis of three impurities along with simvastatin was validated using ICH Q2B (R1) guidelines and it complied with these guidelines. The results of analysis were found to be in the range of 98.14% to 101.89% for all analytes with acceptable accuracy and precision. The method can be used for detection and quantification of synthetic impurities in bulk or formulations of simvastatin
Assessment of Procurement Parameters for A Construction Project
The Procurement of raw material and the handling equipment for the Construction works involve valid sources of supply with varying cost and other liabilities while arriving at the most effective proposal. The abvious parameters for arriving at a purchase decision are cost, lead time, quality of commodity being purchased. Typically supplier are located in a vicinity of the site through their prices could vary amongest themselves as well as the index for the quality. The distant supplier might seem economic for the price while the lead time might not justify the choice. These contrasting needs of the purchasers underline the need for optimal or balanced methods of evaluating the impact on the said resources
An Attempt to Improve Data Security in Text Based Cryptosystem Using Elliptic Curve Cryptography
Data can be debilitated by hackers and spies. Cryptography helps us find better approaches to secure information in digital form. Elliptic Curve Cryptography (ECC) is favorable over numerous cryptographic systems because of smaller keys and quick key generation. This paper proposes a system which intends to provide multifold security in text based communication. The system has two main modules: encryption, and decryption. Encoding scheme which works on variable length text block mapping technique has been exhibited, thereby enhancing data security provided by ECC in text based cryptosystems. To leverage the advantages of ECC, it is being used in many applications. This papers attempts to utilize ECC in text based cryptosystems efficiently
Study of serum sodium and potassium concentration in cataract patients
Background: The present study was aimed to study alterations in levels of sodium and potassium in age-related cataract patients.Methods: 50 senile cataract patients in age group of 50 to 80 years and 50 control group were included for the study. Serum sodium and potassium levels were determined by flame photometry.Results: Significant (<0.0001) increased levels of plasma Na+ in cataract patients (145.06 ± 5.84mEq/lit) were found as compared with controls (141.18 ± 2.67mEq/lit). While Plasma K+ the conc. in cataract patients (4.18 ± 0.34mEq/lit) was not significantly (P = 0.002) increased when compared with controls (4.13 ± 0.32mEq/lit).Conclusion: Na, K-ATPase is responsible for maintaining the correct concentrations of sodium and potassium in lens cells. In ageing, lens fibers undergoes oxidation, and glycation may decrease Na, K-ATPase activity. The asymmetrical distribution of Na, K-ATPase activity in the epithelium and fibers may contribute to ionic currents that flow in and around the lens. So, abnormal elevation of lens sodium can be used as a marker in the opacification of the lens cortex in age-related human cataract
SOLID DISPERSION: STRATEGY TO ENHANCE SOLUBILITY
The solubility behavior of drugs remains one of the most exigent aspects in formulation development.With the advent of combinatorial chemistry and high throughput screening, the number of poorly water soluble compounds has dramatically increased. Among all the newly discovered chemical entities, about 40-45% drugs fail to reach market due to their poor water solubility. Because of solubility problem, bioavailability of drugs gets affected and hence solubility enhancement becomes necessary. Solid dispersions have attracted considerable interest as an efficient means of improving the dissolution rate and hence the bioavailability of drugs. This article reviews the various preparation techniques, carriers used, advantages and limitations of solid dispersions and compiles some of the recent advances. There are various methods available to improve the solubility of the new drug in which solid dispersion emerged promising. A Solid dispersion generally composed of two components- the drug and the polymer matrix. Numerous methods are existing to prepare the solid dispersions such as melting method, solvent evaporation method, fusion method, kneading method, melting method, spray drying method, co-grinding method, lyophilization technique, hot melt extrusion, melt agglomeration, supercritical fluid (SCF) technology etc. Solid dispersion technologies are particularly promising for improving the oral absorption and bioavailability of BCS Class II drugs. The experience with solid dispersions over the last 10-15 years indicates that this is a very fruitful approach in improving the release rate and oral bioavailability of poorly water soluble drugs. Hence, this approach is expected to form a basis for the commercialization of many poorly water-soluble and water-insoluble drugs in their solid-dispersion formulations in the near future. Key words: Dissolution, Solid Dispersion, Solubility, Cellulose Derivatives, Polyethylene glycol
Impact Sensitivity of RDX and Viton Compositions Prepared by Co-precipitation Method
Desensitisation of explosive materials using polymers is an important area in safe utilisation of explosives in various applications. The RDX/viton composition has been developed using co-precipitation method with varying content of viton, ranging from 5 to 35 wt per cent. RDX and viton were dissolved in acetone which is a common solvent for RDX and viton, and then the acetone was extracted from the solution by distillation resulting in homogeneous RDX/viton composition. Infrared spectroscopy studies indicated presence of RDX and viton in the resulting compositions. Thermogravimetric and differential thermal analysis studies made on yielded compositions confirmed that RDX is present in the composition in desired content. The shift in exotherm of RDX/viton composition as compared to RDX showed that polymer-bonded RDX compositions are more stable. The impact sensitivity studies showed that sensitivity of RDX/viton composition decreased with increasing content of viton. The similar trend was observed for friction sensitivity. The co-precipitation method has been found to be advantages to obtain homogeneous composition of RDX and viton (with viton content up to 25 wt per cent) as revealed by linear trend in sensitivity data measurements. It has been demonstrated that the sensitivity of RDX can be tailored within a wide range using viton so as to suit in desired applications.Defence Science Journal, Vol. 65, No. 4, July 2015, pp. 287-291, DOI: http://dx.doi.org/10.14429/dsj.65.864
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