-
[show abstract]
[hide abstract]
ABSTRACT: Screening for insect growth regulatory activity (IGR) of Thevetia nerifolia leaf extracts were evaluated against Spodoptera litura (Fab.). Methanol extract of leaves provided 53.8 % larval mortality, 29.6 % pupation and 22.3 % adult emergence at 2.5 % concentration level. The extract was further subfractioned with solvents of different polarity in search of better IGR activity and chloroform extract was found to be most active in terms of larval mortality (27.5-61.5 %), pupation (28.4-60.2 %) and adult emergence (19.8-52.8 %). GI 50 of the extract was recorded to be 3.02 %. Activity was attributed to the glycosides present in the extract.
-
[show abstract]
[hide abstract]
ABSTRACT: Diabetic retinopathy (DR) is one of the most debilitating disorders of microvasculature of the retina and one of the leading causes of vision loss among the working class worldwide. At present, intravitreal anti-inflammatory (corticosteroids) and anti-angiogenesis (anti-Vascular Endothelial Growth Factor) agents are being used as wide options for the pharmacotherapy of DR and diabetic macular edema (DME). Anti-inflammatory agents (Triamcinolone acetonide and other agents) have shown evidence-based clinical benefits in various randomized clinical trials for the treatment of DR and DME, and also shown improvement in best corrected visual acuity. However, direct intravitreal injections are associated with serious side-effects like cataract and elevation of Intra Ocular Pressure. Despite this, corticosteroid therapy has been effective for DR and DME, therefore current focus is on the development of novel intravitreal steroid delivery devices that release a small quantity over a prolonged period of time. In addition to corticosteroids, anti-angiogenic agents are found to be effective for the treatment of DR and DME. The most popular target of these agents is the subfamily of proteins known as VEGF, whose over-expression is believed to play a role in numerous diseases including DR and Age-related Macular Degeneration. Intravitreal bevacizumab (AvastinĀ®) and Ranibizumab (LucentisĀ®) are gaining popularity as a clinical adjunct to panretinal photocoagulation in patients with proliferative DR. Moreover, Lucentis has been recently approved by the United States Food and Drug Administration for macular edema following retinal vein occlusion. Further, systemic agents (specially, hypoglycemic, hypolipidemic and anti-hypertensive agents) have shown beneficial results in reducing the progression of DR. In conclusion, it can be stated that for the present scenario systematic use of available pharmacotherapy as an adjunct to laser photocoagulation, which is gold standard therapy, can be a useful tool in the prevention of vision loss from DR and related disorders. This article summarizes the up-to-date developments in the pharmacotherapy of DR. Method- Literature search was done on online database, Pubmed, Google Scholar, clinitrials.gov and browsing through individual ophthalmology journals and leading pharmaceutical company websites.
Journal of Postgraduate Medicine 04/2012; 58(2):132-9. · 1.26 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Intraocular pressure (IOP)-lowering effects of investigational antiglaucoma drugs often need comparison with existing drugs, but detailed data showing comparative efficacy of antiglaucoma drugs with different mechanism of action has not been reported so far. This study was designed to establish baseline information of the IOP-lowering effect of three currently used antiglaucoma drugs in three experimental models in rabbits, so that they act as a benchmark for the efficacy evaluation of the future experimental antiglaucoma drugs. The IOP-lowering effect of single-drop application of pilocarpine, timolol and latanoprost was studied in normotensive, water loading and steroid-induced models of glaucoma in rabbits. The noncontact tonometer was used for the first time to estimate IOP in rabbits. The peak IOP-lowering effect of pilocarpine, timolol and latanoprost in normotensive rabbit eye was 18.23%, 20% and 22.56%, respectively. In water-loading model, the maximum protection against the rise in IOP was shown by latanoprost (40.27%), followed by timolol (31.39%) and pilocarpine (28.91%). In steroid-pretreated rabbit eyes, peak IOP-lowering effects of pilocarpine, timolol and latanoprost were 25.65%, 34.21% and 35.06%, respectively. Therefore, the latanoprost was found to be most effective in all three models followed by timolol and pilocarpine. The results of this study can be used for future preclinical investigations for the assessment of IOP-lowering activity of potential antiglaucoma drugs.
Methods and Findings in Experimental and Clinical Pharmacology 01/2008; 29(10):665-71. · 0.93 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Estimation of intraocular pressure in rabbits is often done by indentation tonometry using Schiotz tonometer. The use of Schiotz tonometer for estimation of intraocular pressure requires the use of topical anesthesia, poses risk of infection and injury to cornea and puts the animal under stress. Therefore, in this study noncontact tonometer was used to estimate intraocular pressure in rabbits and the technique is described for the first time. Twenty-five rabbits were subjected to intraocular pressure estimation using Schiotz as well as noncontact tonometer by two independent observers. All intraobserver and interobserver differences were within two standard deviation from the mean, indicating good repeatability and reproducibility of the two methods. A good linear correlation was observed between measurements done by Schiotz and noncontact tonometers with the correlation coefficient (r(2)) of 0.9122 and regression equation y = 1.632x + 4.8684. No significant difference was observed in percent change in intraocular pressure in timolol-treated, water-loaded rabbits using noncontact tonometer and Schiotz tonometer. Noncontact tonometer provides an easy, quick and safe method for intraocular pressure estimation, which is comparable to the conventional method of Schiotz tonometry. Therefore, despite the cost, noncontact tonometry seems to have a greater scope in experimental studies.
Methods and Findings in Experimental and Clinical Pharmacology 29(6):405-9. · 0.93 Impact Factor