R Manavalan

Annamalai University, Anamalainagar, Tamil Nādu, India

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Publications (111)52.73 Total impact

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    ABSTRACT: Export Date: 18 October 2014
    International Journal of Pharma and Bio Sciences 01/2014; 5(1):P606-P611. · 5.12 Impact Factor
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    ABSTRACT: Low-density lipoprotein cholesterol (LDL-C) remains the primary target of lipid-lowering therapy. Achieving LDL-C goals as outlined by the National Cholesterol Education Program Adult Treatment Panel III can be difficult with statins alone; therefore, adjunctive therapy is often indicated to reduce cardiovascular risk. This review provides an overview of beneficial effects of ezetimibe in patients with dyslipidemia when attempting to normalize serum lipid profiles and reduce risk for cardiovascular disease. Ezetimibe, a potent inhibitor of intestinal cholesterol absorption, has been shown to be safe, tolerable and effective at lowering LDL-C, non-high-density lipoprotein cholesterol and apolipoprotein B, each of which has been correlated with improved clinical outcomes, alone or in combination with a statin. Ezetimibe coadministered with statins, a dual inhibition treatment strategy that targets both cholesterol absorption and synthesis, is an effective therapeutic option for dyslipidemia.
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    ABSTRACT: To prepare curcumin-piperine (Cu-Pi) nanoparticles by various methods and to study the effect of various manufacturing parameters on Cu-Pi nanoparticles and to identify a suitable method for the preparation of Cu-Pi nanoparticles to overcome oral bioavailability and cancer cell targeting limitations in the treatment of cancer. Cu-Pi nanoparticles were prepared by thin film hydration method, solid dispersion method, emulsion polymerization method and Fessi method. Optimization was carried out to study the effect of various manufacturing parameter on the Cu-Pi nanoparticles. Out of four methods, Fessi method produced a minimum average particle size of 85.43 nm with a polydispersity index of 0.183 and zeta potential of 29.7 mV. Change of organic solvent (acetone or ethanol) did not have any significant effect on Cu-Pi nanoparticles. However, increase in sonication time, stirring speed, viscosity, use of 1:10:10 ratio of drug/polymer/surfactant, and use of anionic surfactant or combination of anionic surfactant with cationic polymer or combination of non-ionic surfactant with cationic polymer had a significant effect on Cu-Pi nanoparticles. Cu-Pi nanoparticles coated with PEG containing copolymer produced by Fessi method had a minimum average particle size, excellent polydispersity index and optimal zeta potential which fall within the acceptable limits of the study. This dual nanoparticulate drug delivery system appears to be promising to overcome oral bioavailability and cancer cell targeting limitations in the treatment of cancer.
    Asian Pacific Journal of Tropical Biomedicine 11/2012; 2(11):841-8. DOI:10.1016/S2221-1691(12)60241-X
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    ABSTRACT: Developed and optimized a validated isocratic reverse phase HPLC separation of Rosuvastatin, Telmisartan, Ezetimibe and Atorvastatin in pharmaceutical preparation using response surface methodology. The separation was carried out by using phenomenex C18 column (15 cm × 4.6 mm id, 5 μm particle size) and UV detection at 239 nm. The ranges of the independent variables used for the optimization were MeCN: 33–38%, buffer conc.: 10–20 mM and flow rate: 1–2 ml/min. The influence of these independent variables on the output responses: capacity factor of the first peak (k1), resolutions of the 2nd and 3rd peak (Rs2,3), and capacity factor of the fifth peak (k5) were evaluated. Using this strategy, a mathematical model was defined and a response surface was derived for the separation. The three responses were simultaneously optimized by using Derringer’s desirability functions. Optimum conditions chosen for the assay were MeCN, MeOH, 20 mM K2HPO4 (pH 3.0 ± 0.2) solution (34.27:20:45.73 v/v/v) and flow rate 2 ml/min. Total chromatographic analysis time per sample was approximately 10 min. The optimized assay condition was validated as per the ICH guidelines and applied for the quantitative analysis of Rosavel EZ, Avas-EZ and Lipisar 20 tablet. The developed method was simple, accurate and precise. Hence, it can be employed for the routine analysis in quality control laboratories.
    Arabian Journal of Chemistry 03/2012; 107. DOI:10.1016/j.arabjc.2012.03.001 · 2.68 Impact Factor
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    ABSTRACT: Written information play a significant role in supplementing and reinforcing information provided by healthcare professionals. Patient information leaflets (PILs), an inexpensive form of written information which aids the patients and their caregivers to understand the disease and medication. However, poorly designed leaflets may lead to lack of adherence to the proposed treatment. Information in PILs must confirm to the highest standards of scientific accuracy, comprehensive, and designed in a way that is easy to read and understand. Hence, the primary aim of the present study was to assess the quality of patient information leaflet supplied by pharmaceutical manufacturers with respect to readability, design and contents. The study included 35 PILs collected from patients, community pharmacies and hospitals. Readability of PILs was assessed using flesch readability ease formula and flesch kincaid grade level formula. Design and contents of PILs were assessed using predefined score table. The study results showed that 88% of the PILs had reading difficulty, 74% of the PILs had poor design and 60 % of the PILs did not have the necessary information.
  • Research Journal of Pharmacy and Technology 01/2012; 5(4):547-552.
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    ABSTRACT: BACKGROUND: Drug therapy has become so difficult that no one professional is expected to optimize the drug therapy and control drug related problems (DRPs) alone. Despite excellent benefits and safety profile of most medications, DRPs pose a significant risk and adversely affect quality of life of patients. Pharmacists seek to implement pharmaceutical care and measure their effects on patient outcomes. OBJECTIVE: The objective of the study was to identify DRPs amongst inpatients, and the clinical outcome derived from pharmaceutical reactive intervention and passive interventions. METHODOLOGY: The prospective study involves collection of medication details of all the patients and reviewed independently by the pharmacist to identify DRPs and discussed with the physician and suitable reactive interventions were provided and each intervention was graded based on the expected clinical outcome. Similarly passive interventions involved provision drug information services to health care professionals. RESULTS: A total of 386 interventions were made of which 261 were reactive interventions (261DRPs were identified from 189 patients) and 125 were passive interventions. The most common DRPs was drug use without indication (18%) and most common reactive intervention was cessation of drug (20%) and the most frequent passive intervention (drug information query) was related to education and recent advances (51.2%). CONCLUSION: The study demonstrates that reactive interventions of clinical pharmacist improved the patient outcome and passive interventions influenced physicians' decision making in drug therapy.
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    ABSTRACT: Selecting the right method for the preparation of nanoparticles is a crucial decision. A wrong decision can result in the product having to be formulated and developed again. One tool that can be useful in determining the most appropriate method is the Analytical Hierarchy Process (AHP). AHP has been employed in almost all areas related to decision-making problems. In this paper, the results of a case study illustrate that the AHP concept can assist designers in the effective evaluation of various methods available for the preparation of nanoparticles. This paper presents the methodology of selecting the most suitable method for preparing nanoparticles using the analytical hierarchy process.
    Pharmazie 11/2011; 66(11):836-42. DOI:10.1691/ph.2011.1034 · 1.00 Impact Factor
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    P Venkatesan, R Manavalan, K Valliappan
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    ABSTRACT: The aim of present study was to formulate and evaluate the loxoprofen loaded Sustained release microspheres by emulsion solvent evaporation technique. Ethylcellulose, a biocompatible polymer is used as the retardant material. The effects of process conditions such as drug loading, polymer type and solvent type on the characteristics of microspheres were investigated. The prepared microspheres were characterized for their particle size and drug loading and drug release. The in-vitro release studies were carried out in phosphate buffer at pH 7.4. The prepared microspheres were white, free flowing and spherical in shape. The drug-loaded microspheres showed 71.2% of entrapment and the in-vitro release studies showed that Loxoprofen microspheres of 1:3 ratios showed better sustained effect over a period of 8 hours.
    06/2011; 2(3):159-62.
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    ABSTRACT: Recent developments in the technology have initiated scientists to develop orally disintegrating tablets (or) orodispersible tablets with an improved patient compliance and convenience. There are various methods available for the formulation of orodispersible tablets like direct compression, lyophilization (or) freeze drying, sublimation and vaccum drying etc. It is important to incorporate all the quantitative and qualitative criteria such as formulation information, manufacturing skill, supplier, technical information, technical status and machine in the selection process. The fuzzy set theory allows to incorporate unquantifiable, incomplete and partially known information into the decision model. Hence, in the present study fuzzy analytic hierarchical process (FAHP) was applied to select best method for the formulation of orodispersible tablets. Based on the results of FAHP it is concluded that direct compression method is the best method for the formulation of orodispersible tablets.
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    ABSTRACT: Global cancer population is more than 6.75 billion and it is the leading cause of death worldwide. Efforts are being made with the aim to prevent, control and cure the cancer through research activities with the contributions from industries, government and philanthropic funders. However, academic researchers prefer In-vitro cell based assays as they are economically good enough to establish the anticancer activity of a compound/ drug. Assessment of in-vitro anticancer activity is based on the concept of ‘basal’ cytotoxicity of the compounds/ drug which affects the basic functions of cells which in turn leads to cellular damage. Hence anticancer activity/ cytotoxicity can be evaluated by measuring the basic parameter of cellular damage such as increased ATP levels, change in mitochondrial activity, increased concentration of LDH and uptake of fluorescent dye after DNA fragmentation. This review focuses the principle, brief methodology, and latest utilization of the most commonly employed in-vitro cell based anticancer drug screening techniques.
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    ABSTRACT: The purpose of the present study was to systematically investigate some of the important physicochemical properties of loxoprofen loaded microspheres. Loxoprofen, 2-[4-(2-oxocyclopentylmethyl) phenyl]-propionate with two chiral centers, is marketed as an equal parts mixture of four stereoisomers. Loxoprofen sodium is an important non-steroidal anti-inflammatory drug (NSAID) of the 2-arylpropionic acid group used for the treatment of rheumatoid arthritis and osteoarthritis. Almost all drugs are marketed as tablets, capsules or both. Prior to the development of these major dosage forms, it is essential that pertain fundamental physical and chemical properties of the drug molecule and other divided properties of the drug powder are determined. This information decides many of the subsequent events and approaches in formation development.A sustained release microsphere of Loxoprofen was prepared by solvent evaporation method using ethyl cellulose as coating material. So before selection of excipients, the Preformulation study of drug loxoprofen is completed for successful formulation of sustained release microspheres. Preformulation studies included solubility, pKa, dissolution, melting point, assay development, stability in Solution, stability in solid state; microscopy, bulk density, flow properties, excipient compatibility, entrapment efficiency and release profile of microspheres were investigated. INTRODUCTION Nonsteroidal anti-inflammatory drugs (NSAIDs) are widely used for the treatment of pain and inflammation. NSAIDs produce their therapeutic effect by inhibiting the cyclooxygenase (COX) enzymes, which are involved in the biosynthesis of prostaglandins (PGs) [1,2]. Loxoprofen, 2-[4-(2-oxocyclopentylmethyl) phenyl]-propionate with two chiral centres, is marketed as an equal parts mixture of four stereoisomers. Loxoprofen sodium is an important non-steroidal anti-inflammatory drug (NSAID) of the 2-arylpropionic acid group used for the treatment of rheumatoid arthritis and osteoarthritis. Loxoprofen is a prodrug which produces effects after being absorbed from the gastrointestinal tract followed by conversion to an active metabolite. The mechanism of action of loxoprofen is due to inhibition of prostaglandin biosynthesis by its action on cyclooxygenase. After oral administration, loxoprofen sodium is absorbed as the free acid from the gastrointestinal tract rather than the sodium salt, which causes just weak irritation of the gastric mucosa, and is then converted to an active metabolite by reduction of the ketone carbonyl to the trans-OH form. The active isomer has the 2S, 1R', 2'S configuration, which potently inhibits prostaglandin biosynthesis [3–5]. Loxoprofen has an activity to treat inflammatory rheumatoid diseases and relieve acute pain. It is effective against period pains, pain after surgery and fever. Loxoprofen available in pharmaceutical formulations as Tablets and Transdermal patches [6, 7]. Preformulation commences when a newly synthesized drug shows sufficient pharmacologic promise in animal models to warrants evaluation in man. These studies should focus on those physicochemical properties of the new compound that could affect drug performance and development of an efficacious dosage form. A thorough understanding of these properties may ultimately provide a rational for formulation design, or support the need for molecular modification [8].
    International Journal of Research in Pharmaceutical and Biomedical Sciences 01/2011; 2:107-117.
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    ABSTRACT: Cancer is one of the major causes of death worldwide and chemotherapy is a major therapeutic approach for the treatment which may be used alone or combined with other forms of therapy. However, conventional chemotherapy suffers lack of aqueous solubility, lack of selectivity and multidrug resistance. Nanotherapeutics is rapidly progressing aimed to solve several limitations of conventional drug delivery systems. Nonspecific target of cancer chemotherapy leads to damage rapidly proliferating normal cells and can be significantly reduced through folate and transferrin mediated nanotherapeutics which are aimed to target cancerous cells. Multidrug resistance is challenge in cancer chemotherapy which can be significantly reversed by solid lipid nanoparticles, polymeric nanoparticles, mesoporous silica nanoparticles, nanoparticulated chemosensitizer, nanoparticluated poloxamer and magnetic nanoparticles. Hydrophobic nature of chemotherapeutics leads to poor aqueous solubility and low bioavailability which can be overcome by nanocrystals, albumin based nanoparticles, liposomal formulation, polymeric micelles, cyclodextrin and chitosan based nanoparticles. This review focuses the role of nanotherapeutics to overcome lack of selectivity, multidrug resistance and lack of aqueous solubility of conventional cancer chemotherapy.
    Journal of Pharmacy and Pharmaceutical Sciences 01/2011; 14(1):67-77. · 1.68 Impact Factor
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    ABSTRACT: The present study was conducted to evaluate the in vivo antioxidant and lipid peroxidation effect of various extracts of whole plant of Mucuna pruriens (Linn). High fat diet rats showed significant decreased activities of tissue enzymatic and non enzymatic antioxidant. High fat diet induces the oxidative stress in cell by producing reactive oxygen species. Antioxidant enzymes such as superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR), non enzymatic antioxidant glutathione (GSH) and thiobarbituric acid reactive substance levels were increased in the administration of methanolic extract of Mucuna pruriens in high fat diet rats when compared to other two extracts. Hence it is concluded that methanolic extract of Mucuna pruriens were found to have protective action against high fat diet induced oxidative stress in different tissues in rats.
    Asian Journal of Chemistry 01/2011; 23:823-825. · 0.36 Impact Factor
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    ABSTRACT: In the present study was to evaluate the free radical scavenging potential of various extracts from whole plant of Ionidium suffruticosum with the help of three in-vitro antioxidant models were carried out for total antioxidant activity (phosphomolybdic acid method), ferric-reducing antioxidant potential (FRAP) assay and total flavonoids method. Methanolic extract of Ionidium suffruticosum was found to be extremely effective in free radical scavenging activity than that of other two extracts in total antioxidant activity and FRAP methods were tested. High amount of flavonoids were found in methanolic extract of Ionidium suffruticosum. The results obtained in the present study indicate that the methanolic extract of whole plant of Ionidium suffruticosum are a potential source of natural antioxidant.
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  • K Geetha, R Manavalan, D Venkappayya
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    ABSTRACT: Urolithiasis, the process of formation of stones in the kidneys and urinary tract, is the major clinical manifestation of hyperoxaluria. Ethylene glycol feeding resulted in hyperoxaluria with increased renal excretion of oxalate, sodium, calcium and phosphate and a decrease in the excretion of magnesium. Supplementation with an aqueous and alcoholic extract of the leaves of Salvadora persica significantly reduced elevated urinary oxalate levels, indicating a regenerative action on endogenous oxalate synthesis. The deposition of stone-forming constituents in the kidneys of calculogenic rats was also significantly lowered by curative and preventive treatments with the aqueous and alcoholic extracts of Salvadora persica. The high serum creatinine level observed in ethylene glycol-treated rats was also reduced following treatment with the extracts. Histopathological findings showed signs of improvement after treatment with the extracts. These observations led to the conclusion that the aqueous and alcoholic extracts of the leaves of Salvadora persica are endowed with antiurolithiatic properties.
    Methods and Findings in Experimental and Clinical Pharmacology 11/2010; 32(9):623-9. DOI:10.1358/mf.2010.32.9.1549114 · 0.77 Impact Factor