OALib Journal期刊

ISSN: 2333-9721




2014 ( 5 )

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2012 ( 22 )

2011 ( 13 )


匹配条件: “Bhalekar Mangesh” ,找到相关结果约93条。
Statistical optimization of dithranol-loaded solid lipid nanoparticles using factorial design
Gambhire, Makarand Suresh;Bhalekar, Mangesh Ramesh;Gambhire, Vaishali Makarand;
Brazilian Journal of Pharmaceutical Sciences , 2011, DOI: 10.1590/S1984-82502011000300008
Abstract: this study describes a 32 full factorial experimental design to optimize the formulation of dithranol (dth) loaded solid lipid nanoparticles (sln) by the pre-emulsion ultrasonication method. the variables drug: lipid ratio and sonication time were studied at three levels and arranged in a 32 factorial design to study the influence on the response variables particle size and % entrapment efficiency (%ee). from the statistical analysis of data polynomial equations were generated. the particle size and %ee for the 9 batches (r1 to r9) showed a wide variation of 219-348 nm and 51.33- 71.80 %, respectively. the physical characteristics of dth-loaded sln were evaluated using a particle size analyzer, differential scanning calorimetry and x-ray diffraction. the results of the optimized formulation showed an average particle size of 219 nm and entrapment efficiency of 69.88 %. ex-vivo drug penetration using rat skin showed about a 2-fold increase in localization of dth in skin as compared to the marketed preparation of dth.
Eservative Efficacy Testing for Pharmaceutical Products During Stability Studies
Shivani Rao,Mangesh Bhalekar,Ashwini Madgulkar,Saloni Vora
Pharmaceutical Reviews , 2006,
Abstract: Stability studies are performed on all pharmaceutical products before theyare marketed. These include the exposure of the products to stress conditionsfor short time period.Preservatives or antimicrobials are added in some ofthe products in view of protecting it against contaminants during the usageor storage by the consumer.This renders the testing of the efficacy of the preservative as a necessityduring stability studies. Preservative efficacy testing can be done by analyticalor microbiological methods. The article highlights importance of preservativeefficacy testing during stability studies, the regulatory status and needfor harmonization.The rapidmethods for testing preservative testing are also described.
TRIPS: India - Patent Protection for Pharmaceuticals
Ashwini R. Madgulkar,Mangesh Bhalekar,Vinay Kolhe,Shivani Rao
Pharmaceutical Reviews , 2007,
Abstract: The first round of trade negotiations took place while the Preparatory Committee was still working on drafting the Charter because the participants were anxious to begin the process of trade liberalization as soon as possible. Their results were incorporated into the General Agreement (GATT), which was signed in 1947. Having agreed that in implementing their commitments on market access, developed country Members would take fully into account the particular needs and conditions of developing country Members by providing for a greater improvement of opportunities and terms of access for agricultural products of particular interest to these Members, including the fullest liberalization of trade in tropical agricultural products as agreed at the Mid-Term Review, and products of particular importance to the diversification of production from the growing of illicit narcotic crops;
Formulation development of domperidone buccal bioadhesive hydrophilic matrix tablets
Madgulkar Ashwini,Bhalekar Mangesh,Ner Amruta,Wable Nitin
Asian Journal of Pharmaceutics , 2011,
Abstract: Buccoadhesives have long been employed to improve the bioavailability of drugs undergoing significant hepatic first pass metabolism. Domperidone is also reported to have low oral bioavailability due to an extensive hepatic first-pass effect. Buccoadhesive hydrophilic matrices containing Domperidone were prepared using a 32 factorial design. The amounts of Carbopol 934P (CP) and Methocel K100LV (HPMC) were taken as the formulation variables (factors) for optimizing bioadhesion and kinetics of dissolution. A mathematical model was generated for each response parameter. Bioadhesive strength tended to vary quite linearly in an increasing order with an increasing amount of each polymer. The drug release pattern for all the formulation combinations was found to be non Fickian, approaching zero-order kinetics. A suitable combination of two polymers provided adequate bioadhesive strength and fairly regulated the release profile up to 4 hr. The response surfaces and contour plots for each response parameter are presented for further interpretation of the results. The optimum formulations were chosen and their predicted results were found to be in close agreement with the experimental findings.
Novel ion exchange resin-based combination drug-delivery system for treatment of gastro esophageal reflux diseases
Bhalekar, Mangesh Ramesh;Kadam, Nitin Madhukar;Patil, Nilam Hindurao;Gawale, Nitin Somnath;Madgulkar, Ashwini;
Brazilian Journal of Pharmaceutical Sciences , 2010, DOI: 10.1590/S1984-82502010000200021
Abstract: the present study involves preparation and characterization of a combination tablet of ranitidine in immediate release form and domperidone in sustained release form, using ion exchange resins. ranitidine lowers acid secretion, while domperidone release over a prolonged period improves gastric motility thus justifying this combination in gastro esophageal reflux diseases (gerd) and ensuring patient compliance. drug loading was carried out by batch method & resinates were characterized using ftir, xrpd. resinates were formulated as a combination tablet and evaluated for tablet properties & in vitro drug release. resinates provided sustained release of domperidone and immediate release of ranitidine. ir and x-ray studies indicate complexation of drug and resin along with monomolecular distribution of drugs in amorphous form in the resin matrix. the tablets of resinate combination showed good tablet properties. in-vitro drug release gave desired release profiles and ex-vivo drug absorption studies carried out by placing everted rat intestine in dissolution medium indicated statistically significant similarity in absorption from test and marketed formulation. the novelty of this study is that the retardation in release of domperidone from resinates is achieved by presence of weak resin in the formulation.
Ion Exchange Resins in Formulation : An Update
Mrs. Ashwini R. Madgulkar,Dr. Mangesh R. Bhalekar,Mr. Vinay J. Kolhe,Ms. Krishna G. Patel
Pharmaceutical Reviews , 2007,
Abstract: The ion exchange resins in drug delivery system are used to optimize presentation and bioavailability of established therapeutic agents. Formulations based on ion exchange resins are available in the market. Ion Exchange resins have found application not only as drug carriers, but also in a number of areas in formulations and drug delivery. Various applications of resin in drug delivery formulations, recent developments and future scope are discussed in this review. In the continuing search for novel drug delivery system to optimize presentation and bioavailability of established therapeutic agents, Ion exchange resins should be considered as polymers with unique advantageous properties. Ion exchange resins (IER) may be defined as high molecular weight water insoluble polymers containing fixed positively or negatively charged functional groups in their matrix, which have an affinity for oppositely charged counterions 1 . Since the majority of drugs possess an ionic site in their molecule, the charge of the resins provides a means to loosely attach such drugs to insoluble polymers. Various studies has revealed that ion exchange resins are equally suitable for drug delivery technology 2 , including controlled release, transdermal, site specific, fast dissolving, iontophoretically assisted transdermal, nasal, topical and taste masked system.
Optimization of Carboxymethyl-Xyloglucan-Based Tramadol Matrix Tablets Using Simplex Centroid Mixture Design
Ashwini R. Madgulkar,Mangesh R. Bhalekar,Rahul R. Padalkar,Mohseen Y. Shaikh
Journal of Pharmaceutics , 2013, DOI: 10.1155/2013/396468
Abstract: The aim was to determine the release-modifying effect of carboxymethyl xyloglucan for oral drug delivery. Sustained release matrix tablets of tramadol HCl were prepared by wet granulation method using carboxymethyl xyloglucan as matrix forming polymer. HPMC K100M was used in a small amount to control the burst effect which is most commonly seen with natural hydrophilic polymers. A simplex centroid design with three independent variables and two dependent variables was employed to systematically optimize drug release profile. Carboxymethyl xyloglucan , HPMC K100M , and dicalcium phosphate were taken as independent variables. The dependent variables selected were percent of drug release at 2nd hour and at 8th hour . Response surface plots were developed, and optimum formulations were selected on the basis of desirability. The formulated tablets showed anomalous release mechanism and followed matrix drug release kinetics, resulting in regulated and complete release from the tablets within 8 to 10 hours. The polymer carboxymethyl xyloglucan and HPMC K100M had significant effect on drug release from the tablet ( ). Polynomial mathematical models, generated for various response variables using multiple regression analysis, were found to be statistically significant ( ). The statistical models developed for optimization were found to be valid. 1. Introduction Hydrophilic matrices are an interesting option while developing an oral sustained-release formulation. They can be used for controlled release of both water-soluble and water-insoluble drugs. The release behaviour of drugs varies with the nature of the matrix and it is the complex interaction of swelling, diffusion, and erosion processes [1]. Polysaccharides are the choice of material which has been evaluated as hydrophilic matrix for drug delivery system due to their nontoxicity and acceptance by regulating authorities. Xyloglucan is a natural polysaccharide isolated from seed kernel of Tamarindus indica. It is used as ingredient in food and pharmaceutical industry. It has been significantly evaluated for use in hydrophilic drug delivery system. It possesses high viscosity, broad pH tolerance, and swelling and binding properties [2]. This led to its application as release retardant polymer and binder in pharmaceutical industry. In addition to these, other important properties of xyloglucan have been identified recently, which include noncarcinogenicity [3], mucoadhesivity, biocompatibility [4], high drug holding capacity [5], and high thermal stability [6]. This led to its application as excipient in
Chaos Control and Synchronization in Fractional-Order Lorenz-Like System
Sachin Bhalekar
International Journal of Differential Equations , 2012, DOI: 10.1155/2012/623234
Abstract: The present paper deals with fractional-order version of a dynamical system introduced by Chongxin et al. (2006). The chaotic behavior of the system is studied using analytic and numerical methods. The minimum effective dimension is identified for chaos to exist. The chaos in the proposed system is controlled using simple linear feedback controller. We design a controller to place the eigenvalues of the system Jacobian in a stable region. The effectiveness of the controller in eliminating the chaotic behavior from the state trajectories is also demonstrated using numerical simulations. Furthermore, we synchronize the system using nonlinear feedback. 1. Introduction A variety of problems in engineering and natural sciences are modeled using chaotic dynamical systems.A chaotic system is a nonlinear deterministic system possessing complex dynamical behaviors such as being extremely sensitive to tiny variations of initial conditions, unpredictability, and having bounded trajectories in the phase space [1]. Controlling the chaotic behavior in the dynamical systems using some form of control mechanism has recently been the focus of much attention. So many approaches are proposed for chaos control namely, OGY method [2], backstepping design method [3], differential geometric method [4], inverse optimal control [5], sampled-data feedback control [6], adaptive control [7], and so on. One simple approach is the linear feedback control [8]. Linear feedback controllers are easy to implement, they can perform the job automatically, and stabilize the overall control system efficiently [9]. The controllers can also be used to synchronize two identical or distinct chaotic systems [10–13]. Synchronization of chaos refers to a process wherein two chaotic systems adjust a given property of their motion to a common behavior due to a coupling. Synchronization has many applications in secure communications of analog and digital signals [14] and for developing safe and reliable cryptographic systems [15]. Fractional calculus deals with derivatives and integration of arbitrary order [16–18] and has deep and natural connections with many fields of applied mathematics, engineering, and physics. Fractional calculus has wide range of applications in control theory [19], viscoelasticity [20], diffusion [21–25], turbulence, electromagnetism, signal processing [26, 27], and bioengineering [28]. Study of chaos in fractional order dynamical systems and related phenomena is receiving growing attention [29, 30]. I. Grigorenko and E. Grigorenko investigated fractional ordered Lorenz
Infinite-Scroll Attractor Generated by the Complex Pendulum Model
Sachin Bhalekar
International Journal of Analysis , 2013, DOI: 10.1155/2013/368150
Abstract: We report the finding of the simple nonlinear autonomous system exhibiting infinite-scroll attractor. The system is generated from the pendulum equation with complex-valued function. The proposed system is having infinitely many saddle points of index two which are responsible for the infinite-scroll attractor. 1. Introduction A variety of natural systems show a chaotic (aperiodic) behaviour. Such systems depend sensitively on initial data, and one cannot predict the future of the solutions. There are various chaotic systems such as the Lorenz system [1], the Rossler system [2], the Chen system [3], and the Lü system [4] where the dependent variables are the real-valued functions. Though the chaos has been intensively studied over the past several decades, very few articles are devoted to study the complex dynamical systems. Ning and Haken [5] proposed a complex Lorenz system arising in lasers. Wang et al. [6] discussed the applications in genetic networks. Mahmoud and coworkers have studied complex Van der Pol oscillator [7], new complex system [8], complex Duffing oscillator [9], and so forth. Complex multiscroll attractors have a close relationship with complex networks also [10–12]. In this work, we propose a complex pendulum equation exhibiting infinite-scroll attractor. The chaotic phase portraits are plotted, and maximum Lyapunov exponents are given for the different values of the parameter. 2. The Model The real pendulum equation is given by [13] where is constant and is a real valued function. We propose a complex version of (1) given by where is a complex-valued function. The system (2) gives rise to a coupled nonlinear system Using the new variables , , and , the system (3) can be written as the autonomous system of first-order ordinary differential equations given by 2.1. Symmetry Symmetry about the , -axes (or , axes), since (or ) do not change the equations. 2.2. Conservation Consider the following: System is conservative. 2.3. Equilibrium Points and Their Stability It can be checked that the system (4) has infinitely many real equilibrium points given by , where . Jacobian matrix corresponding to the system (4) is Since the eigenvalues of are , , , and , the points are stable equilibrium points. The eigenvalues of are , , , and . An equilibrium point is called a saddle point if the Jacobian matrix at has at least one eigenvalue with negative real part (stable) and one eigenvalue with nonnegative real part (unstable). A saddle point is said to have index one (/two) if there is exactly one (/two) unstable eigenvalue/s. It is established in
Predicting maximum voluntary ventilation in normal healthy individuals using indirect inspiratory muscle strength measurements: a correlation study  [PDF]
Rohit Sontakke, Mangesh Deore, Dhara Kothari
Health (Health) , 2010, DOI: 10.4236/health.2010.24043
Abstract: Maximum Voluntary Ventilation (MVV), one of the components of Pulmonary Function Testing (PFT), has multiple uses. Various factors including the inspiratory muscle strength (IMS) influence its magnitude. Our aim was to quantify the IMS indirectly using an economical and non invasive bedside assessment tool, determine its association with MVV and then develop a predictive equation for MVV. 41 healthy non-athletic physical therapy students participated in the study. IMS measurement was performed with a sphygmomanometer. Average of the three net deflections in sphygmomanometer following deepest possible breaths was taken as indirect measurement of IMS in mm of Hg. MVV was measured according to ATS guidelines using a spirometer. Results from the data analysis revealed a significant correlation between IMS and MVV(r = 0.83, p < 0.001) and the coefficient of determination = 0.68. So, we developed a regression equation: Y = 1.9669(X) + 49.838 with SEE: 13.02L/min and ANOVA for the equation was (F=68.9, p < 0.001). Hence, it can be concluded that a strong correlation between the indirect IMS and MVV was established and a predictive equation to estimate MVV was developed. This equation proved to have a high predictive value with a small error of estimation. This indicates that the value of the indirect IMS measurement obtained using the sphygmomanometer can be used to estimate MVV in normal healthy individuals without the use of a conventional spirometer.

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