Thiruvananthapuram, India
Thiruvananthapuram, India

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Singha S.,University of Calcutta | Datta H.,Regional Institute of Ophthalmology | Dasgupta A.K.,University of Calcutta
Journal of Nanoscience and Nanotechnology | Year: 2010

Citrate synthase is a heat labile enzyme showing a loss of activity even in response to a modest shift of temperature (35°-45°C). Gold nanoparticle is shown to prevent the thermal aggregation of this enzyme. The chaperon like activity of the nanoparticle diminishes if the particle size is reduced from 40 nm to 20 nm keeping the atomic concentration of gold constant. This implies that the effect is not merely due to enhanced surface area offered by the nano-surfaces. The effect is reversible as the protein separated out from nanoparticles behaves similar to control. The observed coupling between chaperon activity of the nanoparticle and its cluster forming ability is illustrated in terms of a thermal cage model. Copyright © 2010 American Scientific Publishers All rights reserved.

Bandyopadhyay S.K.,Regional Institute of Ophthalmology
Journal of the Indian Medical Association | Year: 2012

To study the macular thickness and peripapillary nerve fibre layer thickness in children with anisometropic amblyopia, a prospective non-randomised case series study was undertaken among 39 children (25 boys and 14 girls) aged between 5 and 16 years. This study was carried out between January 2010 and April 2011. The peripapillary retinal nerve fibre layer (RNFL) thickness and macular layer thickness was measured using optical coherence tomography (OCT), the RNFL thickness and the macular layer thickness of the amblyopic eye was assessed and compared to the normal eye of the same subject. It was found that macular layer thickness in the amblyopic eye was greater than that of the macular thickness in the normal eye. The mean macular layer thickness in the amblyopic eyes was 229.589 microm with a standard deviation of -+/- 31.9149 microm. The mean macular layer thickness in the normal eyes of these children was 206.8717 microm with a standard deviation of +/- 28.490 microm, the p-value was 0.00141 which is much lesser than 0.005 and hence is strongly statistically significant. However the mean RNFL thickness in the amblyopic eye was 104.454 microm with a standard deviation of +/- 22.244 microm. The mean RNFL thickness of the normal eye was 108.2746 microm with a SD of +/- 19.370 microm. The p-value in this case being 0.4246 which is statistically insignificant. It is conducted that macular layer thickness is raised in the amblyopic eye of children with anisometropic amblyopia though the RNFL thickness is not.

Kusumesh R.,Regional Institute of Ophthalmology | Vanathi M.,All India Institute of Medical Sciences
Oman Journal of Ophthalmology | Year: 2015

Purpose: Early presentation of rejection facilitates early initiation of treatment which can favor a reversible rejection and better outcome. We analyzed the incidence, clinical features including rejection-treatment period and outcomes following graft rejection in our series of pediatric corneal graft.Materials and Methods: Case records of pediatric penetrating keratoplasty (PK) were reviewed retrospectively, and parameters noted demographic profile, indication of surgery, surgery-rejection period, rejection-treatment interval, graft outcome, and complications.Results: PK was performed in 66 eyes of 66 children <12 years, with an average follow-up of 21.12 ± 11.36 months (range 4-48 month). The median age at the time of surgery was 4.0 years (range 2 months to 12 years). Most of the children belonged to rural background. Scarring after keratitis (22, 33.4%) was the most common indication. Graft rejection occurred in eight eyes (12.12%) (acquired nontraumatic - 3, congenital hereditary endothelial dystrophy [CHED] - 2, nonCHED - 1, congenital glaucoma - 1, regraft - 1). The mean surgery-rejection period was 10.5 ± 7.3 months and mean rejection-treatment interval was 10.9 ± 7.02 days.Conclusion: This study showed irreversible graft rejection was the leading cause of graft failure of pediatric PK. Though, the incidence (12.1%) of graft rejection in current study was not high, but the percentage of reversal (25%) was one of the lowest in literature because of delayed presentation and longer interval between corneal graft rejection and treatment. In addition, categorization of the type of graft rejection was very difficult and cumbersome in pediatric patients. © 2015 Farjadnia M, et al.

Sasikala V.,Kerala University | Rooban B.N.,Kerala University | Sahasranamam V.,Regional Institute of Ophthalmology | Abraham A.,Kerala University
Graefe's Archive for Clinical and Experimental Ophthalmology | Year: 2013

Background: Cataract, the leading cause of blindness, is associated with oxidative damage and protein modification in the lens. The present study was carried out to assess the efficacy of rutin on rat-lens crystallins in selenite-induced in-vivo cataract models. Methods: Eight-day-old Sprague-Dawley rat pups were grouped as control (G I), experimental (G II) and rutin-treated (G III). The rat pups in G II, and G III received a single subcutaneous injection of sodium selenite (4 μg/g body weight) and G I received a single subcutaneous injection of sterile water on the 10th day. The treatment groups (G III) were administered with rutin (1 μg/g body weight) respectively from the 8th to 15th day. Cataract was visualized from the 16th day. Lens crystallins (α, β, and γ) were isolated by size exclusion chromatography. Chaperone activity of isolated crystallins was measured by heat, DTT, and oxidation-induced aggregation and refolding assays. Concentration of total protein (soluble and insoluble) and SDS-PAGE analysis of soluble proteins were also done. Results: Treatment with rutin prevented the loss of α crystallin chaperone property, and protein insolubilization prevailed during selenite-induced cataract. Conclusions: These results suggest the therapeutic potential of rutin, a bioflavonoid, against selenite-induced cataract, which has been reported in this paper for the first time. The work assumes significance, as this is a novel approach in modulating the chaperone activity of lens crystallins in selenite-induced cataract by a natural product. © 2013 Springer-Verlag Berlin Heidelberg.

Archana S.,Regional Institute of Ophthalmology
Nepalese journal of ophthalmology : a biannual peer-reviewed academic journal of the Nepal Ophthalmic Society : NEPJOPH | Year: 2011

Cataract surgery techniques have improved a lot over the years from couching to the latest micro-incision cataract surgery. To compare the temporal sclero-corneal and clear corneal tunnel incisions in patients undergoing manual small-incision cataract surgery (SICS) with respect to the surgically-induced astigmatism. The present study included 60 patients who underwent manual SICS with posterior chamber intraocular lens implantation. Group A comprised of 30 patients, selected randomly, who underwent sutureless manual SICS through 6 mm curvilinear clear corneal tunnel incision made temporally and Group B comprised of 30 patients, selected randomly, who underwent sutureless manual SICS through 6 mm straight sclero-corneal tunnel made temporally. The patients were assessed at 1 week, 2 weeks, 1 month and 2 months post-operatively and visual acuity and keratometry findings were recorded. The amount of surgically induced astigmatism was calculated using Holladay's formula. Numerical data were compared between the two groups using unpaired Student's t-test. The p value of less than 0.50 was considered significant. The mean induced astigmatism in Group A was 2.69 ± 0.84 D at 1 week, 2.31 ± 0.77 D at 2 weeks; 2.03 ± 0.82 D at 4 weeks and 1.98 ± 0.54 D at 8 weeks post-operatively. In group B, it was 1.85 ± 0.62 D, 1.56 ± 0.54 D, 1.35 ± 0.49 D and 1.34 ±0.45 D at 1 week, 2 weeks, 4 weeks and 8 weeks postoperatively. Uncorrected visual acuity (UCVA) of 20/ 20 was seen in 20 % of patients in group A and in 40 % in group B at 8 weeks postoperatively. Surgically-induced astigmatism is significantly higher in clear corneal manual SICS than in sclero-corneal. Our study confirmed the safety and improvement in visual acuity after small-incision cataract surgery using sclero-corneal tunnel incision. © NEPjOPH.

Thakur S.K.,Regional Institute of Ophthalmology
Nepalese journal of ophthalmology : a biannual peer-reviewed academic journal of the Nepal Ophthalmic Society : NEPJOPH | Year: 2011

The corneal endothelium plays an important role in maintaining the dehydrated state and the transparency of the cornea. Some degree of endothelial cell loss invariably occurs in all types of cataract surgery but the amount of endothelial cell loss varies with the surgical technique. To evaluate the density of the central corneal endothelial cells before and after small incision cataract surgery (SICS) with posterior chamber intraocular lens (PC IOL) implantation. A total of 100 eyes of 100 patients undergoing SICS with PC IOL were included in the study. Endothelial cell density was measured with non-contact specular microscope pre-operatively and post-operatively on Day 1, Day 7 and at one month. The mean endothelial cell count pre-operatively was 2673 ± 358.85 cells / sq mm while post-operatively at 1 month it was 2249.77 ± 354.04 cells / sq mm. There is 15.83 % reduction in endothelial cell count after SICS with PC IOL implantation, which is comparable with other modes of cataract surgery like extra-capsular cataract extraction and phacoemulsification. © NEPjOPH.

Sen D.,Regional Institute of Ophthalmology | Ghosh S.,Regional Institute of Ophthalmology | Roy D.,Regional Institute of Ophthalmology
Diabetes and Metabolic Syndrome: Clinical Research and Reviews | Year: 2015

Background Association of C-reactive protein (CRP) and body mass index (BMI) with diabetic retinopathy (DR) has conflicting reports. Method Sixty diabetes patients each with DR (Group A), no DR (Group B) and 60 healthy volunteers (control, group C) were studied. CRP was measured. BMI was calculated. Result Significant difference in CRP was observed between groups A & B (p = 0.000) and A & C (p = 0.007). No significant difference in BMI was observed. Central macular thickness correlated positively with CRP and negatively with BMI. Conclusion We observed strong association of CRP with DR and no significant relationship between DR and BMI. © 2014 Diabetes India. Published by Elsevier Ltd. All rights reserved.

Ghosh S.,Regional Institute of Ophthalmology
Indian journal of public health | Year: 2012

To evaluate pattern of visual impairment in school children from low-income families in Kolkata, India, an institutional cross-sectional study was conducted among 2570 children of 10 primary schools. Ocular examination including refraction was done and pattern of visual impairment and refractive error was studied. The age range was 6-14 years. Refractive error was seen in 14.7%. Only 4 children were already wearing correction. Myopia and hypermetropia was present in 307 (11.9%) and 65 (2.5%) children, respectively. Visual acuity of less than 6/12 in better eye was present in 109 (4.2%) and 5 (0.2%) children pre- and post-correction, respectively. Eighteen children had amblyopia. Although prevalence of refractive error in this group is less compared to school children of all income categories reported from other cities of India, it is more compared to school children of all income categories from the same city. Refractive error mostly remains uncorrected in this group.

Rooban B.N.,Kerala University | Sasikala V.,Kerala University | Sahasranamam V.,Regional Institute of Ophthalmology | Abraham A.,Kerala University
Graefe's Archive for Clinical and Experimental Ophthalmology | Year: 2011

Purpose: Recent evidence suggests that oxidative stress plays a significant role in the development of cataract. The present study sought to evaluate the efficacy of flavonoid fraction of Vitex negundo (FVN) in preventing the toxicity induced by sodium selenite in vitro culture condition. Methods: Enucleated rat lenses were maintained in organ culture containing DMEM medium alone (G I), supplemented with 0.1mM sodium selenite (G II), sodium selenite + 20 μg/ml quercetin (G III) and sodium selenite + 50 μg/ml FVN (G IV). Treatment was from the second to fifth day, while selenite administration was done on the third day. After the experimental period, lenses were taken out and the activities of superoxide dismutase (SOD), catalase, Ca2+ ATPase, levels of reduced glutathione (GSH), calcium, reactive oxygen species (ROS), thiobarbituric acid reactive substances (TBARS), and sulfhydryl content were studied. Results: Morphological examination revealed dense vacuolization and loss of cortical transparency in G II compared to control and treated group. The mean activities of the enzymes SOD, catalase and Ca2+ ATPase, levels of GSH and sulfhydryl content were significantly reduced in lenses of G II compared to control. In addition, the mean levels of ROS, calcium and TBARS were elevated in G II compared to control. However, these changes were modulated by FVN treatment to further strengthen its protective role over selenite cataract. Conclusion: These results suggest that FVN treatment prevented selenite toxicity and cataractogenesis by maintaining antioxidant status, calcium homeostasis, protecting sulfhydryl group, and decreasing oxidative stress in lens, which may be due to its protective effects. © 2011 Springer-Verlag.

Rooban B.N.,Kerala University | Sasikala V.,Kerala University | Sahasranamam V.,Regional Institute of Ophthalmology | Abraham A.,Kerala University
Molecular Vision | Year: 2011

Purpose: Cataract is the leading cause of blindness and is associated with oxidative damage and protein modification in the lens. In the present study, we have employed proteomic and microscopic approaches to investigate the attenuation of selenite cataract by the flavonoids from Vitex negundo (FVN). Methods: To demonstrate this attenuation, Sprague-Dawley rat pups were divided into control (G I), selenite induced (G II), and selenite + FVN treated (G III). Cataract was induced by single subcutaneous injection of sodium selenite (4 mg/ Kg bodyweight) on the 10th day and FVN (1 mg/Kg bodyweight) administered intraperitoneally from the 8th to the 15th day. Results: Our study indicated that chaperone property of α-crystallin and soluble protein levels were reduced in the selenite induced group. Post translational modifications identified by two dimensional-polyacrylamide gel electrophoresis (2DPAGE) and immunoblot analysis revealed the loss of cytoskeletal proteins in selenite induced group. Damage of lenticular membrane and abnormal fiber structure were observed by electron microscopy. Conclusions: The results of this study suggest that FVN modulated selenite induced cataractogensis in rat pups by preventing loss of chaperone property, various changes in lens proteins, and lens structure, further strengthening its protective role.

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