Ophthalmology Commons^™

The Effect Of Endothelin-1 On The Expression Of Cdk Inhibitors P21 & P27 In Bovine Corneal Endothelial Cells, Lakshmi Reddy Bollu

Masters Theses & Specialist Projects

Mammalian corneal endothelial cells are considered to be non-proliferative due to the arrest of cells at the G1 phase of the cell cycle. The purpose of this study was to determine whether the down regulation of cyclin dependant kinase inhibitors (p21cip1 and p27kip1) levels by Endothelin-1 (ET-1), would overcome the G1 phase arrest and promote cell cycle progression and proliferation in cultured BCECs (Bovine corneal endothelial cells). BCECs were isolated from bovine corneas and cultured in DMEM supplemented with 10% serum. 5-Bromo 2-deoxy Uridine (BrdU) incorporation was determined in serum starved cultures in 24-well plates as a measure of cell …

Vegf-A As An Inhibitor Of Angiogenesis And Methods Of Using Same, Jayakrishna Ambati

Ophthalmology and Visual Science Faculty Patents

The invention relates to methods and compositions for the treatment or prevention of ocular angiogenesis and neovascularization associated with neovascular disease. Administration of vascular endothelial growth factor (VEGF)-A into the eye when macrophage infiltration is reduced inhibits ocular angiogenesis.

Use Of Home Remedies And Traditional Medicines For The Treatment Of Common Eye Ailments In Pakistan: A Qualitative Study, Khabir Ahmad, Muhammad Aman Khan, Muhammad Babar Khan, Muhammad Daud Khan, Azam Ali, Clare Gilbert

Department of Surgery Docs

Purpose: Qualitative studies focusing on the use of home remedies and traditional medicines for eye health are lacking. We explored the use of eye remedies and traditional eye medicines (referred to hereafter as “eye remedies/TEM”) in Pakistan’s Abbottabad district.

Material and Methods: We conducted face-to-face key informant interviews with 16 teachers (8 men, 8 women). Participants were asked to list eye remedies/TEM used in their home or in areas where they lived. They were also asked to specify conditions for which each one of them is used. Their responses were noted manually and the interview scripts were translated from Urdu …

Central Corneal Thickness Of Pakistani Adults, Roomasa Channa, Fazia Mir, Mahnaz Naveed Shah, Azam Ali, Khabir Ahmad

Section of Ophthalmology

Objective: To determine the average central corneal thickness (CCT) of healthy adults in the ophthalmology clinic of a tertiary care hospital of Pakistan.
Methods: This was a cross-sectional study conducted in the ophthalmology clinics of Aga Khan University Hospital, Karachi Pakistan. One hundred normal subjects (200 eyes) were studied. An ultrasound pachymeter was used to measure CCT.
Results: The mean (+/- SD) age of the study population was 44.29 +/- 15.18 years with a median of 47 years (range: 16-73). Twenty three percent of the subjects had diabetes mellitus, 29% hypertension and 6% had history of ischaemic heart disease. The …

Gender Differences And Delay In Presentation Of Childhood Squint, Tanveer Anjum Chaudhry, Aziz Khan, Muhammad Bilal Salman Khan, Khabir Ahmad

Section of Ophthalmology

Objective: To assess gender differences and delay in presentation of childhood squint in a tertiary care hospital.
Methods: It was a series of children presenting with squint at the Aga Khan University Hospital, Karachi, Pakistan. We retrospectively studied the cases presenting between February 2000 and July 2007.
Results: A total of 107 children with squint were seen. Of these, 55 (52.4%) were girls. A statistically significant difference was observed between the mean age at presentation (+/- SD) of boys and girls (3 years and 5 months vs 4 years and 5 months p: < 0.05). Girls had a greater mean (SD) and median (range) delay in squint presentation than had boys (2 year 4 months +/- 3 years vs 3 years +/- 2 year 8 months) and 2 year 3 months (1 month to 12 years) vs 1 year 3 months (1 month to 14 years), respectively. Overall amblyopia was present in 25.3% (23/91) children. Girls also had a higher burden of amblyopia compared with their male counterparts though the difference was not statistically significant (P = 0.09).
Conclusion: There was a significant gender difference …

Cases Of Subconjunctival Hemorrhage After A Joy Ride, Roomasa Channa, Sana Shoukat Memon, Tanveer Anjum Chaudhry, Khabir Ahmad

Department of Surgery Docs

No abstract provided.

Visual Impairment And Eye Care Among Older Americans: Secondary Analysis Of The Behavioral Risk Factor Surveillance System (Brfss), Amy L. Freeland

Dissertations

The aim of this three-paper format dissertation is to explore three topics relevant to public health and vision loss. The three papers are independent studies, yet build upon each other by first describing the population of people aged 40 years and older in the United States in terms of visual impairment, diagnosed eye disease/injury, and their use of eye care, and then next exploring the factors that influence eye care use for both the general population and the subpopulation of people with diagnosed diabetes. The first paper provides a state-level examination of the characteristics of people aged 40 years and …

Colocalization Of Increased Transforming Growth Factor-Β-Induced Protein (Tgfbip) And Clusterin In Fuchs Endothelial Corneal Dystrophy, Ula V. Jurkunas, Maya Bitar, Ian Rawe

Ophthalmology

PURPOSE: To investigate the differential expression of TGFBIp in normal human and Fuchs endothelial corneal dystrophy (FECD) endothelial cell-Descemet’s membrane (HCEC-DM) complex, and to asses the structural role of TGFBIp and clusterin (CLU) in guttae formation.

METHODS: HCEC-DM complex was dissected from stroma in normal and FECD samples. Proteins were separated by 2-D gel electrophoresis and subjected to proteomic analysis. N-terminal processing of TGFBIp was detected by Western blot analysis with two separate antibodies against the N- and C-terminal regions of TGFBIp. Expression of TGFBI mRNA was compared by using real-time PCR. Subcellular localization of TGFBIp and CLU in corneal …

Accumulation Of Rhodopsin In Late Endosomes Triggers Photoreceptor Cell Degeneration, Yashodhan Chinchore, Amitavo Mitra, Patrick J. Dolph, Norbert Perrimon

Dartmouth Scholarship

Progressive retinal degeneration is the underlying feature of many human retinal dystrophies. Previous work using Drosophila as a model system and analysis of specific mutations in human rhodopsin have uncovered a connection between rhodopsin endocytosis and retinal degeneration. In these mutants, rhodopsin and its regulatory protein arrestin form stable complexes, and endocytosis of these complexes causes photoreceptor cell death. In this study we show that the internalized rhodopsin is not degraded in the lysosome but instead accumulates in the late endosomes. Using mutants that are defective in late endosome to lysosome trafficking, we were able to show that rhodopsin accumulates …

Vitreo-Retinal Traction And Anastrozole Use, Alvin Eisner, Emily J. Thielman, Julie Falardeau, John T. Vetto

Community Health Faculty Publications and Presentations

Purpose—This study tested a prediction stemming from the hypothesis that anastrozole users experience heightened vitreo-retinal traction. This hypothesis was based on the knowledge that menopause increases the risk of intraocular tractional events such as posterior vitreous detachments (PVDs).

Methods—Retinal thickness was measured for 3 groups of amenorrheic women: (1) anastrozole users and (2) tamoxifen users undergoing adjuvant therapy for early-stage breast cancer, and (3) control subjects not using hormonal medication. Foveal shape indices were derived for subjects without PVDs.

Results—For anastrozole users, the distance to the temporal side of the fovea became less than the distance to …

Molecular Confirmation Of The Causes Of Inherited Visual Impairment In Northern Pakistan, Mehreen Adhi, Yasmin Rashid, Syed Hussain Jafri, Chris F. Inglehearn, Martin Mckibbin

Section of Ophthalmology

Families with inherited visual impairment were identified and examined from January 2000 to December 2005 and given a clinical diagnosis. Known genes and loci were screened for mutations or linkage at Institute of Ophthalmology and Neurosciences, University of Leeds, in order to provide molecular confirmation. Inherited retinal disease was the most common cause of inherited visual impairment in 38 of 57 families (66.6%) with Leber's congenital amaurosis, rod-cone dystrophy and cone-rod dystrophy being the most common diagnoses in 22, 8 and 3 families respectively. Anterior segment dysgenesis was diagnosed in 8 families (14%). Mutations in known genes or linkage to …

Trichostatin A Inhibits Corneal Haze In Vitro And In Vivo, Ajay Sharma, Maneesh M. Mehan, Sunilima Sinha, John W. Cowden, Rajiv R. Mohan

Pharmacy Faculty Articles and Research

PURPOSE. Trichostatin A (TSA), a histone deacetylase inhibitor, has been shown to suppress TGF- –induced fibrogenesis in many nonocular tissues. The authors evaluated TSA cytotoxicity and its antifibrogenic activity on TGF- –driven fibrosis in the cornea with the use of in vitro and in vivo models.

METHODS. Human corneal fibroblasts (HSFs) were used for in vitro studies, and New Zealand White rabbits were used for in vivo studies. Haze in the rabbit cornea was produced with photorefractive keratectomy (PRK) using excimer laser. Trypan blue exclusion and MTT assays evaluated TSA cytotoxicity to the cornea. Density of haze in the rabbit …

Locus Of Control And Adjustment To Vision Loss Among People With Age Related Macular Degeneration, Delinda Stinnette

Walden Dissertations and Doctoral Studies

People aged 65 and older account for 12.8% of the population and for 30% of all visually impaired individuals. Age-related Macular Degeneration (ARMD) has been identified as a significant public health issue, with a potential 8 million Americans at risk. While the literature supports a connection between LOC and adaptation to ARMD, there is a gap in the current literature supporting this relationship even when other factors are controlled (i.e. age, sex, education, type of ARMD, when diagnosed, the use of medical treatments, the use of visual assistance devices, participant engagement in rehabilitation, and depression). The present survey study used …

High-Resolution Analysis Of Dna Copy Number Alterations In Patients With Primary Open-Angle Glaucoma., Khaled K Abu-Amero, Ali Hellani, Patrick Bender, George L. Spaeth, Jonathan Myers, L Jay Katz, Marlene Moster, Thomas M Bosley

Wills Eye Hospital Papers

PURPOSE: To determine whether patients with isolated primary open-angle glaucoma (POAG) have evidence of chromosomal copy number alterations.

METHODS: Twenty-seven Caucasian and African-American POAG patients and 12 ethnically matched controls were carefully screened for possible glaucoma and tested for chromosomal copy number alterations using high resolution array comparative genomic hybridization.

RESULTS: No POAG patient had evidence of chromosomal copy number alterations when compared to normal ethnically matched controls. Additionally, there was no evidence of somatic mosaicism in any tested POAG patient.

CONCLUSIONS: Chromosomal deletions and/or duplications were not detected in POAG patients as compared to controls. Other chromosomal imbalances such …

Infectious Keratitis Associated With Contact Lens Use, Misty Dawn Harvey

All-Inclusive List of Electronic Theses and Dissertations

In March 2006, ophthalmologists noticed increased Fusarium keratitis in patients wearing soft contact lenses; the etiology was that of Fusarium solani. By May of 2006, CDC reported receiving a total of 130 confirmed cases of Fusarium keratitis across 26 states and one territory; of the 118 who could identify the lens solution they had used, 64% reported using Bausch & Lomb's ReNu with Moistureloc ©,while 18% reported using only non-Bausch & Lomb products. The association between Fusarium keratitis and ReNu with Moistureloc was not clear. Nevertheless, Bausch & Lomb withdrew Moistureloc solutions worldwide. In earlier laboratory tests using standard methods …

Decreased Expression Of Peroxiredoxins In Fuchs’ Endothelial Dystrophy, Ula V. Jurkunas, Ian Rawe, Maya Bitar, Cheng Zhu, Deshea L. Harris, Kathryn Colby, Nancy C. Joyce

Ophthalmology

Purpose: To compare the relative expression of peroxiredoxin (Prx) proteins in normal human corneal endothelium with endothelium in corneas affected by Fuchs’ endothelial dystrophy (FED) and between normal human endothelium and epithelial/stromal tissue.

Methods: Human corneal endothelial cell-Descemet’s membrane (HCEC-DM) complexes from normal and FED corneal buttons were dissected from the epithelium/stroma. For proteomic analysis, HCEC-DM protein extracts were separated by using two-dimensional gel electrophoresis. Relative differences in protein spot density was analyzed. Proteins of interest, including Prx isoforms, were identified by MALDI-TOF (matrix-assisted desorption ionization-time of flight) mass spectrometry. Western blot analysis compared the relative expression of Prx isoforms …

Increased Clusterin Expression In Fuchs’ Endothelial Dystrophy, Ula V. Jurkunas, Maya Bitar, Ian Rawe, Deshea L. Harris, Kathryn Colby, Nancy C. Joyce

Ophthalmology

Purpose: To compare the relative expression of peroxiredoxin (Prx) proteins in normal human corneal endothelium with endothelium in corneas affected by Fuchs’ endothelial dystrophy (FED) and between normal human endothelium and epithelial/stromal tissue.

Methods: Human corneal endothelial cell-Descemet’s membrane (HCEC-DM) complexes from normal and FED corneal buttons were dissected from the epithelium/stroma. For proteomic analysis, HCEC-DM protein extracts were separated by using two-dimensional gel electrophoresis. Relative differences in protein spot density was analyzed. Proteins of interest, including Prx isoforms, were identified by MALDI-TOF (matrix-assisted desorption ionization-time of flight) mass spectrometry. Western blot analysis compared the relative expression of Prx isoforms …

Progressive Optic Neuropathy In Congenital Glaucoma Associated With The Sirsasana Yoga Posture, Daniela S. Monteiro De Barros, Md; Sheila Bazzaz, Md, Moataz E. Gheith, Md, Ghada A. Siam, Md, Marlene R. Moster, Md

Wills Eye Hospital Papers

The authors describe a case of progressive optic neuropathy in a patient with congenital glaucoma who had routinely practiced the Sirsasana (headstand) yoga posture for several years. Ophthalmic examination included best-corrected visual acuity, anterior segment examination, indirect oplithalmoscopy, ultrasound pachymetry for central corneal thickness, and intraocular pressure before, during, and after maintaining the Sirsasana posture for 5 minutes. Intraocular pressure increased significantly during the Sirsasana posture. Transient elevation in intraocular pressure during yoga exercises may lead to progressive glaucomatous optic neuropathy, especially in susceptible patients with congenital glaucoma.

Feedback From Horizontal Cells To Rod Photoreceptors In Vertebrate Retina., Wallace B. Thoreson, Norbert Babai, Theodore M M. Bartoletti

Journal Articles: Ophthalmology

Retinal horizontal cells (HCs) provide negative feedback to cones, but, largely because annular illumination fails to evoke a depolarizing response in rods, it is widely believed that there is no feedback from HCs to rods. However, feedback from HCs to cones involves small changes in the calcium current (I(Ca)) that do not always generate detectable depolarizing responses. We therefore recorded I(Ca) directly from rods to test whether they were modulated by feedback from HCs. To circumvent problems presented by overlapping receptive fields of HCs and rods, we manipulated the membrane potential of voltage-clamped HCs while simultaneously recording from rods in …

Retinopathy Of Prematurity: Frequency And Risk Factors In A Tertiary Care Hospital In Karachi, Pakistan, Ather M. Taqui, Reema Syed, Tanveer Anjum Chaudhry, Khabir Ahmad, Muhammad S. Salat

Section of Ophthalmology

Introduction: To determine the frequency of Retinopathy of Prematurity (ROP) in the premature infants born in a tertiary care hospital and to determine the risk factors associated with it.
Methods: This was a retrospective analysis of premature infants with birth weight < or = 1500 grams or gestational ago < or = 32 weeks, admitted to the Neonatal Intensive Care Unit of a tertiary care hospital in a three year period. The infants underwent eye examinations between their 4th and 7th week of life. Univariate and multiple logistic regression analysis were performed to determine the association between risk factors and ROP development.
Results: Sixty eight infants were included in the analysis. Out of these, 22 (32.4%) developed ROP (inclusive of all stages) and 14 (20.6%) developed threshold disease. Multiple logistic regression analysis revealed that low gestational age, sepsis and respiratory distress syndrome were independent predictors for the development of ROP.
Conclusion: The frequency of ROP in our hospital was on the …

Cannabinoids: A Novel Treatment Strategy For Retinal Neurodegenerative Disorders, Sandeep Samudre

Theses and Dissertations in Biomedical Sciences

Synthetic and naturally occurring cannabinoids are known to decrease intraocular pressure (IOP). Glaucomatous damage to the retina and optic nerve progresses even after therapy to maintain normal intraocular pressure (IOP). Topical application of cannabinoids decreases IOP while not affecting blood pressure or heart rate. Based upon their effects on other tissues, we hypothesize that these analogs reduce IOP and may also confer direct neuroprotective effects on the retina, possibly via CB1 and/or CB2 receptors. The purpose of this study is to determine if the newly synthesized CB agonists, lipid soluble O-1812 (CB 1), and water soluble O-2545 (CB 1

The …

Conjunctival Malignant Melanoma Mimicking As A Chalazion, Sana Shoukat Memon, Roomasa Channa, Tanveer Anjum Chaudhry, Khabir Ahmad

Department of Surgery Docs

No abstract provided.

The Color Appearance Of Stimuli Detected Via Short-Wavelength-Sensitive Cones: Comparisons With Visual Adaptation And Visual Field Data For Peri- Or Post-Menopausal Women Under 70 Years Of Age, Alvin Eisner, Maureen D. Toomey

Community Health Faculty Publications and Presentations

Dynamics of foveal light adaptation for vision mediated via short-wavelength-sensitive (SWS) cones were compared for two groups of healthy amenorrheic (peri- or post-menopausal) women not using hormonal medication. Each subject was assigned to a group based on the color name – “lavender” (~2/3 of all subjects) or "white" (~1/3 of all subjects) – chosen in a forced-response paradigm to best describe a threshold-level 440-nm test presented on a larger 3.6 log td 580-nm background that had been viewed for ~5 minutes. During the first 20–30 seconds after this 3.6 log td background abruptly replaced a much dimmer background, the threshold …

Interferon Associated Retinopathy, Hassan Khan, Kamran Hamid, Aga Hassan Feroze

Section of Ophthalmology

We describe a case of retinopathy with swollen optic nerve head (ONH) in a hepatitis C patient treated with combination of interferon and ribavirin. A 33-years old man presented with sudden bilateral visual loss and headache. On examination, the Visual Acuity of right eye and left eye was hand movement and counting fingers respectively. Right fundus showed ONH swelling, healthy macula, with tortuous dilated vessels and small scattered, intra retinal haemorrhages. Retinopathy was only present in the right eye, however, poor vision in both eyes suggested neurovisual involvement.

Pdgf-Driven Proliferation, Migration, And Il8 Chemokine Secretion In Human Corneal Fibroblasts Involve Jak2-Stat3 Signaling Pathway, Neeraj Vij, Ajay Sharma, Mahesh Thakkar, Sunilima Sinha, Rajiv R. Mohan

Pharmacy Faculty Articles and Research

Purpose: Platelet-derived growth factor (PDGF) is associated with corneal fibroblast migration and proliferation and plays an important role in corneal wound healing. However, the intracellular mechanisms of PDGF-mediated functions in corneal fibroblasts are poorly understood. We tested the hypothesis that PDGF functional activities in the cornea involve the Janus kinase-2/signal transducers and activators of transcription-3 (JAK2-STAT3) signaling pathway and whether PDGF induces the expression of suppressors of cytokine signaling 3 (SOCS3), belonging to the novel family of feedback regulators of cytokine and growth factor activities.

Methods: Human corneal fibroblast (HSF) cultures were used as an in vitro model for functional …

Transcriptional Regulatory Network Analysis During Epithelial-Mesenchymal Transformation Of Retinal Pigment Epithelium., Craig H Pratt, Rajanikanth Vadigepalli, Praveen Chakravarthula, Gregory E Gonye, Nancy J Philp, Gerald B Grunwald

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

PURPOSE: Phenotypic transformation of retinal pigment epithelial (RPE) cells contributes to the onset and progression of ocular proliferative disorders such as proliferative vitreoretinopathy (PVR). The formation of epiretinal membranes in PVR may involve an epithelial-mesenchymal transformation (EMT) of RPE cells as part of an aberrant wound healing response. While the underlying mechanism remains unclear, this likely involves changes in RPE cell gene expression under the control of specific transcription factors (TFs). Thus, the purpose of the present study was to identify TFs that may play a role in this process.

METHODS: Regulatory regions of genes that are differentially regulated during …

The Effectiveness Of Prophylactic Eye Drops On The Reversal Of Uv-Light Induced Cataracts, Contessa Bly Bowman

Theses and Dissertations

Cataracts are a cloudiness of the lens within the eye which obstructs vision. They are found in many species including rats, dogs, and humans. Vision is hindered where this "cloudiness", made of water build up and broken crystalline, proteins take form. Oculvet is an eye medication, used by veterinarians, containing carnosine as its active ingredient. Topical application of carnosine is reported to be an effective treatment for the prevention and removal of pre-existing cataracts. For this experiment, Sprague- Dawley rats were anesthetized and exposed to ultraviolet radiation, UVB and UVC. They were divided into four groups (n = 32), three …

Imatinib Challenge Dismissed In India, Khabir Ahmad

Department of Surgery Docs

No abstract provided.

A Serratia Marcescens Oxyr Homolog Mediates Surface Attachment And Biofilm Formation, Robert M. Q. Shanks, Nicholas A. Stella, Eric J. Kalivoda, Megan R. Doe

Dartmouth Scholarship

OxyR is a conserved bacterial transcription factor with a regulatory role in oxidative stress response. From a genetic screen for genes that modulate biofilm formation in the opportunistic pathogen Serratia marcescens, mutations in an oxyR homolog and predicted fimbria structural genes were identified. S. marcescens oxyR mutants were severely impaired in biofilm formation, in contrast to the hyperbiofilm phenotype exhibited by oxyR mutants of Escherichia coli and Burkholderia pseudomallei. Further analysis revealed that OxyR plays a role in the primary attachment of cells to a surface. Similar to what is observed in other bacterial species, S. marcescens OxyR …

Blindness In Children At The Ida Rieu School For The Blind And Deaf, Sadia Javed Khan, Afshan Hassan, Laila Khalid, Uzma Karim, Erum Hashmi, Fariha Gul, Imtiaz Jehan

Community Health Sciences

Objective: To identify the causes of blindness at the Ida Rieu school for the blind and deaf, Karachi, Pakistan.Methods: A cross sectional study was conducted at the Ida Rieu School for the blind and deaf. The data collected from medical record of students was entered into the WHO/PBL eye examination form for children with blindness and low vision.Results: Records of 144 pupils aged between 4-30 years were reviewed, including 67% males and 33% females. One third (31%) children had visual impairment (< 6/18-6/60) and 69% were blind (< 3/60-NPL). The commonest anatomical site was retina (41%) and whole globe (20%). The etiology was unknown in 49% cases. In 33% of cases, the data suggested hereditary cause as the etiology, 40% of cases were preventable and 13% treatable.CONCLUSION: Avoidable causes of blindness were seenin 53% of children, 58% of which were preventable and 19 were treatable.