Thesis (Ph. D.)--University of Hong Kong, 2007. / Also available in print.

Thesis supervisor: Mona K. Garvin. Includes bibliographic references (p. 55-57).

Thesis (M. Med. Sc.)--University of Hong Kong, 2007.

Dissertação (mestrado)—Universidade de Brasília, Faculdade de Ciências da Saúde, Programa de Pós-Graduação em Ciências da Saúde, 2013. / Submitted by Alaíde Gonçalves dos Santos (alaide@unb.br) on 2013-08-21T11:42:05Z No. of bitstreams: 1 2013_AdrianaSobralLourenço.pdf: 1732302 bytes, checksum: 15787f088c67e2b094dea116c83ad9cd (MD5) / Approved for entry into archive by Guimaraes Jacqueline(jacqueline.guimaraes@bce.unb.br) on 2013-08-21T15:52:29Z (GMT) No. of bitstreams: 1 2013_AdrianaSobralLourenço.pdf: 1732302 bytes, checksum: 15787f088c67e2b094dea116c83ad9cd (MD5) / Made available in DSpace on 2013-08-21T15:52:29Z (GMT). No. of bitstreams: 1 2013_AdrianaSobralLourenço.pdf: 1732302 bytes, checksum: 15787f088c67e2b094dea116c83ad9cd (MD5) / Objetivo: Este estudo tem como objetivo avaliar a influência do cristalino no teste de sobrecarga hídrica (TSH) em indivíduos portadores de glaucoma primário de ângulo aberto (GPAA) e sadios portadores de catarata e pseudofácicos. Método: Estudo transversal composto por 80 olhos de 80 pacientes, sendo 40 pacientes glaucomatosos e 40 sadios, por sua vez subdivididos em dois grupos compostos de 20 pacientes fácicos e outro de pacientes pseudofácicos. Os pacientes foram submetidos à curva ambulatorial (CA) e ao TSH. Resultados: A média dos picos da pressão intra-ocular (Po) na CA foi maior nos pacientes fácicos glaucomatosos que nos pseudofácicos glaucomatosos (p=0,045), assim como os picos da Po no TSH (p=0,00364). Os pacientes fácicos controles apresentaram média dos picos da Po maior que os pseudofácicos controles (p=0,012). A média dos picos da Po no TSH também foi maior no subgrupo fácico controle que no pseudofácico controle (p=0,017). Os pacientes fácicos glaucomatosos apresentaram média dos picos da Po na CA maior que os pseudofácicos controles (p<0,0001), assim como no TSH (p<0,0001). Entre subgrupos fácico controle e pseudofácico glaucoma não houve diferença estatisticamente significativa quando foi avaliada a média dos picos da Po na CA (p=0,399) e no TSH (p=0,65). Comparando os fácicos glaucomatosos e fácicos controles, não houve diferença estatisticamente significativa em relação à média dos picos da Po na CA (p=0,2156); houve significância estatística quando comparadas as médias dos picos da Po no TSH (0,0054). Comparando os subgrupos pseudofácico glaucoma e pseudofácico controle, não houve diferença estatisticamente significativa quando as médias dos picos da Po foram avaliadas tanto na CA (p=0,1043) quanto no TSH (p=0,075). Conclusão: Nos pacientes fácicos os picos pressóricos aferidos tanto no TSH quanto na CA foram maiores que nos pacientes pseudofácicos. _______________________________________________________________________________________ ABSTRACT / Purpose: The aim of this study was to evaluate the lens influence on water drinking test in patients with open angle glaucoma and health individuals, phakics and pseudophakics. Methods: Transversal study includes 80 eyes of 80 patients, 40 patients with open angle glaucoma and 40 health individuals. Each group of 40 persons was divided in two groups of 20 individuals, one with cataract and another pseudophakic. The patients was submitted a modified tensional curve and water drinking test. Results: Comparing phakics glaucomatous patients and pseudophakics glaucomatous patients, the intraocular pressure (IOP) mean peaks was higher in phakics individuals in modified tensional curve (p=0,045) and water drinking test (p=0,00364). The IOP mean peaks in modified tensional curve was higher in phakics controls patients when they was compared to pseudophakics controls (p=0,012). The IOP mean peaks on water drinking test was higher in phakic control group too (p=0,017). The glaucomatous phakics patients had IOP mean peaks in modified tensional curve higher than the pseudophakics controls (p<0,0001) and in water drinking test too (p<0,0001). When the phakic control group and pseudophakic glaucomatous group were compared there was no statistically significance on IOP mean peaks in modified tensional (p=0,399) and water drinking test (p=0,65). There was no statiscally significance on IOP mean peaks in modified tensional curve (p=0,2156) when the phakics glaucomatous patients and phakics controls were compared. But there was statistically significance between these groups in water drinking test (p=0,0054). Comparing the pseudophakic glaucoma group and pseudophakic control group there was no significance on IOP mean peaks on modified tensional curve (p=0,1043) and water drinking test too (p=0,075). Conclusion: In phakics patients the IOP peaks measureds were higher in modified tensional and water drinking test.

Orientadores : Vital Paulino Costa, Newton Kara Jose / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas / Made available in DSpace on 2018-07-27T17:41:33Z (GMT). No. of bitstreams: 1 Gondim_EvertonLima_D.pdf: 25582763 bytes, checksum: 31bf68f4f7ad2f1330f5edad72328be2 (MD5) Previous issue date: 2001 / Resumo: o objetivo deste trabalho é determinar os efeitos da vasopressina na PIO, em coelhos, após administração intracerebroventricular, endovenosa ou intra-ocular e identificar qual o mecanismo receptor responsável por estes efeitos. Administraram-se doses crescentes de vasopressina em coelhos conscientes pelas seguintes vias: (1) intracerebroventricular por meio de injeções no terceiro ventrículo, (2) endovenosa por meio de injeções na veia auricular marginal e (3) intra-ocular por meio de injeções intravítreas ou na câmara anterior. Injeções de solução salina isotônica serviram como controle. A PIO foi monitorada durante 6 horas, permitindo a geração de curvas de dose-resposta. A seguir, os efeitos da vasopressina na PIO foram examinados após a administração de um antagonista seletivo dos receptores Vl. Realizaram-se ainda injeções intracerebroventriculares e endovenosas de desmopressina, um agonista seletivo dos receptores V2 da vasopressina. As respostas na PIO foram analisadas utilizando-se o teste t de Student. Constatou-se uma elevação dose-dependente da PIO após lll Jeções intracerebroventriculares de vasopressina. Após injeções endovenosas, intravítreas ou na câmara anterior de vasopressina, observaram-se reduções significativas da PIO. Os efeitos da vasopressina na PIO foram bloqueados com o tratamento prévio com o antagonista dos receptores V1. Após administração de desmopressina por meio de injeções intracerebroventriculares ou endovenosas, não foram observados efeitos na PIO. Concluiu-se que injeções intracerebroventriculares de vasopressina promovem uma elevação da PIO de coelhos. Injeções endovenosas, intravítreas ou na câmara anterior de vasopressina promovem redução da PIO de coelhos. Os efeitos da vasopressina na PIO de coelhos após injeções intracerebroventriculares ou endovenosas são mediados pelos receptores Vl. A redução da PIO de coelhos observada após administração endovenosa de vasopressina ocorre, pelo menos em parte, por mecanismo de ação intra-ocular mediado pelos receptores V1 / Abstract: Purpose. To compare the central, peripheral and local effects of exogenous arginine vasopressin on intra-ocular pressure (IOP) in rabbits and to identify the receptor mechanisms associated with these effects. Methods. Young adult New Zealand albino rabbits were housed under a daily 12-hour light and 12-hour dark cyc1e. In the early light period, bolus injections of vasopressin or desmopressin (a specific V2receptor agonist) were given either to the central nervous system (CNS) or to the ear vein in groups of 7-9 conscious rabbits. Test peptides were delivered to the CNS through an implanted cannula to the 3rdventric1e. Injections of isotonic saline solution served as the controI. Bilateral IOP was monitored for up to 6 hours and dose-response curves were generated. Central and peripheral effects of vasopressin on IOP were further examined by the pretreatment with a selective VI receptor antagonist. To investigate whether or not vasopressin can influence IOP by intra-ocular mechanisms, we performed intravitreal or anterior chamber injections of vasopressin in groups of 6 rabbits. The contralateral eye received isotonic saline solution as the controI. Bilateral IOP was monitored for up to 6 hours. The responses in IOP were analyzed using the Student' s t-test. Results. A dose-dependent elevation of IOP was observed after gintracerebroventricular injections of vasopressin. The IOP elevation was completely blocked by the pretreatment with the VI antagonist given to the 3rdventric1e. Following intravenous injections of vasopressin, significant reductions of IOP were observed. The reductions of IOP were completely blocked by the pretreatment with the VI antagonist. Intracerebroventricular or intravenous injections of desmopressin had no effect on IOP. Following the intravitreal or anterior chamber injection of vasopressin, significant reductions ofIOP were observed. Intravitreal or anterior chamber pretreatment with the V- 1 receptor antagonist prevented the reductions ofIOP following the intravenous injection of vasopressm Conclusions. Bolus intracerebroventricular and intravenous injections of vasopressin cause opposite effects on IOP. Intracerebroventricular injections ofvasopressin increase IOP while peripheral and local injections of vasopressin decrease IOP. The central and peripheral effects ofvasopressin on IOP are mediated via the VI receptors / Doutorado / Oftalmologia / Doutor em Ciências Médicas

PURPOSE. The purpose of this study was to quantify the biomechanical response of human posterior ocular tissues from donors of various racioethnic groups to better understand how differences in these properties may play a role in the racioethnic health disparities known to exist in glaucoma. METHODS. Sequential digital image correlation (S-DIC) was used to measure the pressure-induced surface deformations of 23 normal human posterior poles from three racioethnic groups: African descent (AD), European descent (ED), and Hispanic ethnicity (HIS). Regional in-plane principal strains were compared across three zones: the optic nerve stump (ONS), the peripapillary (PP) sclera, and non-PP sclera. RESULTS. The PP scleral tensile strains were found to be lower for ED eyes compared with AD and HIS eyes at 15 mm Hg (P = 0.024 and 0.039, respectively). The mean compressive strains were significantly higher for AD eyes compared with ED eyes at 15 mm Hg (P = 0.018). We also found that the relationship between tensile strain and pressure was significant for those of ED and HIS eyes (P < 0.001 and P = 0.004, respectively), whereas it was not significant for those of AD (P = 0.392). CONCLUSIONS. Our results suggest that, assuming glaucomatous nerve loss is caused by mechanical strains in the vicinity of the optic nerve head, the mechanism of increased glaucoma prevalence may be different in those of AD versus HIS. Our ONS strain analysis also suggested that it may be important to account for ONS geometry and material properties in future scleral biomechanical analysis.

Thesis (M.A.)--Boston University / During the past ten years argon laser trabeculoplasty (ALT) has evolved from a novel to a commonplace intervention in the management of open-angle glaucoma. Despite its widespread usage, the exact effect of ALT on the trabecular meshwork is only partially understood. Nonetheless, its effect of lowering intraocular pressure through enhancement of aqueous humor outflow is well documented. Laser photocoagulation of the trabecular meshwork focally destroys, but also diffusely stimulated trabecular meshwork cells. The laser induced shape alterations in the trabecular meshwork are thought to influence aqueous humor outflow only at very high intraocular pressure levels. It appears more probable that most of the aqueous humor outflow occurring after ALT results from laser induced metabolic changes within the cells of the trabecular meshwork. This review chronicles the history of the use of the laser in glaucoma management, the clinical experience and some of the experimental studies which have been conducted to answer the questions regarding the mechanism of action of ALT.

archives@tulane.edu / Glaucoma is a debilitating and insidious disease and is the world’s leading cause of irreversible blindness. There have been many proposed innovations in the ophthalmology space though few have successfully been implemented in humans. The gap between proof of concept studies and market launch has been termed the “valley of death.” The Blake, Ayyala, and John research group have been endeavoring to bring two drug delivery systems through this “valley of death” for the last ten years. These products aim to solve a common problem in glaucoma surgery: post-surgical fibrosis resulting in the need for revision surgery. The two drug systems are a poly(hydroxyl ethyl methacrylate) hydrogel loaded with mitomycin C and a biodegradable poly(lactic-co-glycolic acid) matrix loaded with 5-fluorouracil and mitomycin C. These anti-fibrotics, when released into the surgical site, successfully reduced scar tissue formation in animal models. To translate these technologies to market, we created methods to interrogate their synthesis, studied their properties after sterilization, and performed longitudinal studies to determine their stability. For the pHEMA-based drug delivery system, we introduced a new casting method and compared it to previous studies. This new method reduced casting time two-fold and increased lot-to-lot reproducibility. We also developed an assay for quantifying the amount of drug loaded into each hydrogel. Using this assay, we reduced the loading time of the hydrogels two-fold by more than 5 days. The product was then gamma and e-beam sterilized to determine how sterilization would affect the hydrogel. We showed that the hydrogel releases mitomycin C more slowly after gamma irradiation than after e-beam and that both releases were slower than unsterilized material. This indicates that the hydrogel has cross-linked during the sterilization process. For the PLGA-based drug delivery system, we developed a solvent extraction method for quantifying the amount of drug in each piece. We then used this assay to interrogate different steps in the manufacturing process. We discovered the need for a new casting method using a positive displacement pipette. We tested the homogeneity of the 5-fluorouracil within the polymer matrix and discovered that drug distribution in our films was uniform. We ensured that we could reproducibly create lots of these films. Then, we tested the stability of this drug delivery system after gamma irradiation. We performed a longitudinal shelf-life study to see how temperature and the presence of air could affect the system during 3 months of storage. We then lyophilized our product and compared e-beam and gamma sterilization techniques. These studies contributed to an investigational new drug filing with the FDA which is the next milestone for a drug product before first-in-human trials. / 1 / Mitchell Layton Fullerton

No description available.

Apart from associated genes, a candidate causative gene NTF4 was screened and two novel putative mutations (Gly157Ala and Ala182Val) detected, likely accounting for 0.29% of POAG. In the exploration of new POAG genes, two functional candidates CNTF and SPARC were screened and excluded. / Differential association profiles were found for SNPs in/near CAV1, CAV2, CYP46A1, LMX1B, PLXDC2, TLR4, TMTC2, ZP4 and 2p16.3. SNPs at CAV1, CAV2, TLR4 and 2p16.3 were associated with POAG, whilst SNPs around other genes were unlikely to be risk factors for the disease, at least in Chinese. TLR4 rs7037117 was associated with HTG in southern Chinese (P=0.0016, OR=2.72, recessive model). SNP rs1533428 at 2p16.3 showed an age-specific association of with late-onset POAG (age at diagnosis >60 years; P=1.14x10-5, OR=2.02, dominant model) but not with juvenile- and adult-onset POAG. Moreover, rs1533428 formed a joint effect with rs7037117 to confer stronger risk to HTG (P=2.8x10 -4, OR=4.53). Besides, rs4236601 near the CAV1 and CAV2 genes was confirmed as a risk factor for POAG and another two protective SNPs rs6975771 and rs959173 were identified; moreover, that the risk and protective alleles were located in different haplotypes suggested multiple roles of the genes. / Glaucoma is a group of degenerative optic neuropathies and the leading cause of irreversible blindness worldwide. Primary open-angle glaucoma (POAG) is a major type of glaucoma in most populations. It is classified into high-tension glaucoma (HTG) and normal-tension glaucoma (NTG) according to the level of intraocular pressure. POAG has complex etiology. It could be monogenic or caused by multiple risk factors. At least 22 linkage loci have been mapped, with 3 genes (MYOC, OPTN, and WDR36 ) identified. Also, more than 30 susceptibility genes have been reported, many of which, however, remain unverified. / In the mapping of the causal gene at GLC1N, a truncation mutation c.1090delT in the MEGF11 gene was found to be cosegregated with glaucoma in the GLC1N-linked pedigree. Subsequent identification of c.1090delT in an unrelated JOAG patient supported that it is a disease-causing mutation. The identification of four splice-site mutations (IVS17+2insT, IVS17-4C>G, IVS17-2A>G and c.2472A>C) exclusively in patients provided further evidence supporting MEGF11 as a causative gene for POAG. Mutations in this gene likely account for approximately 1% of POAG or 2% of JOAG. / This thesis describes our work on the identification of new POAG genes by using a 3-tiered strategy: (1) to identify new genetic profiles of variants around the CAV1, CAV2, CYP46A1, LMX1B, NTF4, PLXDC2, TLR4, TMTC2, ZP4 genes and the 2p16.3 locus; (2) to evaluate CNTF and SPARC as disease genes for POAG; and (3) to map the causal gene at the GLC1N locus for juvenile-onset POAG (JOAG). / Totally 1645 unrelated participants were enrolled, including a Hong Kong cohort of 281 HTG, 311 NTG and 248 controls, a Shantou cohort of 102 HTG, 28 NTG and 298 controls and, a Beijing cohort of 177 HTG and 200 controls. Also involved were members of the GLC1M-linked Philippine pedigree and the GLC1N-linked Hong Kong pedigree with JOAG, which have been previously described. / Chen, Lijia. / Adviser: Chi Pui Pang. / Source: Dissertation Abstracts International, Volume: 73-02, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (leaves 185-210). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [201-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.