Recent evidence suggests that the thyroid hormone L-thyroxine (T 4 ) stimulates growth of cancer cells via a plasma membrane receptor on integrin A V B 3 . The contribution of this recently described receptor for thyroid hormone and receptor-based stimulation of cellular mitogen-activated protein kinase [MAPK; extracellular signal-regulated kinase 1/2 (ERK1/2)] activity, to enhancement of cell proliferation by thyroid hormone was quantitated functionally and by immunologic means in three glioma cell lines exposed to T 4 . At concentrations of 1 to 100 nmol/L, T 4 caused proliferation of C6, F98, and GL261 cells, measured by accumulation of proliferating cell nuclear antigen (PCNA) and radiolabeled thymidine incorporation. This effect was inhibited by the T 4 analogue, tetraiodothyroacetic acid, and by an A V B 3 RGD recognition site peptide, both of which block T 4 binding to integrin A V B 3 but are not agonists. Activation of MAPK by T 4 was similarly inhibited by tetraiodothyroacetic acid and the RGD peptide. The thyroid hormone 3,5,3 ¶-triiodo-L-thyronine (T 3 ) and T 4 were equipotent stimulators of PCNA accumulation in C6, F98, and GL261 cells, but physiologic concentrations of T 3 are 50-fold lower than those of T 4 . In conclusion, our studies suggest that glioblastoma cells are thyroid hormone dependent and provide a molecular basis for recent clinical observations that induction of mild hypothyroidism may improve duration of survival in glioblastoma patients. The present experiments infer a novel cell membrane receptor-mediated basis for the growth-promoting activity of thyroid hormone in such tumors and suggest new therapeutic approaches to the treatment of patients with glioblastoma. (Cancer Res 2006; 66(14): 7270-5)

Gender inequity in use of cataract surgical services persists in the low- and middle-income countries. It is estimated in this study that blindness and severe visual impairment from cataract could be reduced by around 11% in the low- and middle-income countries if women were to receive cataract surgery at the same rate as men. Additional effort globally is needed to ensure that women receive the benefits of cataract surgery at the same rate as men.

Primary angle closure glaucoma was the predominant form of glaucoma followed by PAC, and POAG suggesting that the pattern in Saudi Arabia could be quite different from that reported for primary glaucomas in the Western literature. In addition, pseudoexfoliation was the most common form of secondary open and closed angle glaucoma. These results indicate the need for a national intervention program for early detection and referral of glaucoma cases in order to prevent significant visual loss. There is also a need for a community based assessment to determine the prevalence of glaucoma as a baseline for future intervention.

To investigate which matrix metalloproteinases (MMPs) are more likely to be involved in the angiogenic process in proliferative diabetic retinopathy (PDR), we measured the levels of MMPs in the vitreous fluid from patients with PDR and controls and correlated these levels with the levels of vascular endothelial growth factor (VEGF). Vitreous samples from 32 PDR and 24 nondiabetic patients were studied by mosaic multiplex MMPs enzyme-linked immunosorbent assay (ELISA), single ELISA, Western blot and zymography analysis. Epiretinal membranes from 11 patients with PDR were studied by immunohistochemistry. MMP-8 and MMP-13 were not detected. ELISA, Western blot and gelatin ymography assays revealed significant increases in the expression levels of MMP-1, MMP-7, MMP-9 and VEGF in vitreous samples from PDR patients compared to nondiabetic controls, whereas MMP-2 and MMP-3 were not upregulated in vitreous samples from PDR patients. Significant correlations existed between ELISA and zymography assays for the quantitation of MMP-2 (r=0.407; p=0.039) and MMP-9 (r=0.711; p<0.001). Significant correlations were observed between levels of VEGF and levels of MMP-1 (r=0.845; P<0.001) and MMP-9 (r=0.775; p<0.001), and between levels of MMP-1 and MMP-9 (r=0.857; p<0.001). In epiretinal membranes, cytoplasmic immunoreactivity for MMP-9 was present in vascular endothelial cells and stromal monocytes/macrophages and neutrophils. Our findings suggest that among the MMPs measured, MMP-1 and MMP-9 may contribute to the angiogenic switch in PDR.

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Objectives:To determine the prevalence and causes of blindness and diabetic retinopathy (DR) in Jazan district, Southern Saudi Arabia.Methods:Using the standardized Rapid Assessment for Avoidable Blindness (RAAB) and DR cross-sectional methodology, 3800 subjects were randomly selected from the population of ≥50 years of age in Jazan, Saudi Arabia between November 2011 and January 2012. Participants underwent screening comprised of interview, random blood glucose test, and ophthalmic assessment including visual acuity (VA) and fundus examination. Among participants with VA <6/18 in either eye, the cause(s) of visual impairment was determined. Participants were classified as diabetic if they had previous diagnoses of diabetes, or random blood glucose >200 mg/dl. Diabetic participants were assessed for DR using dilated fundus examination. All data were recorded using the RAAB + DR standardized forms.Results:The prevalence of bilateral blindness <3/60 was 3.3% (95% confidence interval [CI]: 2.74 - 3.90). Cataract was the leading cause of blindness (58.6%); followed by posterior segment diseases (20%), which included DR (7; 3.3%). The prevalence of diabetes mellitus (DM) was 22.4%, (95% CI: 21.09 - 23.79), among them; 27.8% had DR. The prevalence of sight-threatening DR was 5.7%.Conclusion:The prevalence of DM and the corresponding proportion of DR in this region is lower than that reported in other regions of Saudi Arabia. However, the prevalence of blindness not related to DR is relatively higher than the other studies.

PPV with JLP for optic disc pit maculopathy had similar functional and anatomic outcomes compared with vitrectomy without JLP.

Retinopathy of Prematurity (ROP) is one of the leading causes of bilateral blindness in childhood. Early detection and effective treatment can prevent blindness. Efficient and timely screening examination of the retina by an experienced ophthalmologist who deals with preterm neonates with ROP is the mainstay in the management of this disease. All neonatologists and pediatricians who care for these at-risk preterm neonates should also be aware of this timing. This practical guideline intends to provide guidance to ophthalmologists, neonatologists and allied health care professionals in Saudi Arabia on current indications for screening and management of retinopathy of prematurity to prevent or minimize subsequent complications. This practical guideline was led by the National Eye Health Program (NEHP) and Neonatology Services Improvement Program at Ministry of Health (MOH), furthermore it has been solicited and endorsed from both Saudi Ophthalmological Society (SOS) and Saudi Neonatology Society (SNS).