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2015

Uchiyama E, Faez S, Nasir H, Unizony S, Plenge R, Papaliodis G, Sobrin L. Accuracy of the International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) as a research tool for identification of patients with uveitis and scleritis.. Ophthalmic Epidemiol. 2015;22(2):139–41.

PURPOSE: To report on the accuracy of the International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) codes for identifying patients with polymyalgia rheumatica (PMR) and concurrent noninfectious inflammatory ocular conditions in a large healthcare organization database. METHODS: Queries for patients with PMR and uveitis or scleritis were executed in two general teaching hospitals' databases. Patients with ocular infections or other rheumatologic conditions were excluded. Patients with PMR and ocular inflammation were identified, and medical records were reviewed to confirm accuracy. RESULTS: The query identified 10,697 patients with the ICD-9-CM code for PMR and 4154 patients with the codes for noninfectious inflammatory ocular conditions. The number of patients with both PMR and noninfectious uveitis or scleritis by ICD-9-CM codes was 66. On detailed review of the charts of these 66 patients, 31 (47%) had a clinical diagnosis of PMR, 43 (65%) had noninfectious uveitis or scleritis, and only 20 (30%) had PMR with concurrent noninfectious uveitis or scleritis confirmed based on clinical notes. CONCLUSIONS: While the use of ICD-9-CM codes has been validated for medical research of common diseases, our results suggest that ICD-9-CM codes may be of limited value for epidemiological investigations of diseases which can be more difficult to diagnose. The ICD-9-CM codes for rarer diseases (PMR, uveitis and scleritis) did not reflect the true clinical problem in a large proportion of our patients. This is particularly true when coding is performed by physicians outside the area of specialty of the diagnosis.

Weis, Schmidt, Maamar, Raj, Lin, Tóth, Riedmann, Raddatz, Seitz, Ho, Lyko, Linhart. Inhibition of intestinal tumor formation by deletion of the DNA methyltransferase 3a. Oncogene. 2015;34(14):1822–30.
Aberrant de novo methylation of DNA is considered an important mediator of tumorigenesis. To investigate the role of de novo DNA methyltransferase 3a (Dnmt3a) in intestinal tumor development, we analyzed the expression of Dnmt3a in murine colon crypts, murine colon adenomas and human colorectal cancer using RNA fluorescence in situ hybridization (FISH), quantitative PCR and immunostaining. Following conditional deletion of Dnmt3a in the colon of APC((Min/+)) mice, we analyzed tumor numbers, genotype of macroadenomas and laser dissected microadenomas, global and regional DNA methylation and gene expression. Our results showed increased Dnmt3a expression in colon adenomas of APC((Min/+)) mice and human colorectal cancer samples when compared with control tissue. Interestingly, in tumor tissue, RNA FISH analysis showed highest Dnmt3a expression in Lgr5-positive stem/progenitor cells. Deletion of Dnmt3a in APC((Min/+)) mice reduced colon tumor numbers by ~40%. Remaining adenomas and microadenomas almost exclusively contained the non-recombined Dnmt3a allele; no tumors composed of the inactivated Dnmt3a allele were detected. DNA methylation was reduced at the Oct4, Nanog, Tff2 and Cdkn1c promoters and expression of the tumor-suppressor genes Tff2 and Cdkn1c was increased. In conclusion, our results show that Dnmt3a is predominantly expressed in the stem/progenitor cell compartment of tumors and that deletion of Dnmt3a inhibits the earliest stages of intestinal tumor development.
Aung T, Ozaki M, Mizoguchi T, Allingham R, Li Z, Haripriya A, Nakano S, Uebe S, Harder J, Chan A, Lee MC, Burdon K, Astakhov Y, Abu-Amero K, Zenteno J, Nilgün Y, Zarnowski T, Pakravan M, Safieh LA, Jia L, Wang YX, Williams S, Paoli D, Schlottmann P, Huang L, Sim KS, Foo JN, Nakano M, Ikeda Y, Kumar R, Ueno M, Manabe SI, Hayashi K, Kazama S, Ideta R, Mori Y, Miyata K, Sugiyama K, Higashide T, Chihara E, Inoue K, Ishiko S, Yoshida A, Yanagi M, Kiuchi Y, Aihara M, Ohashi T, Sakurai T, Sugimoto T, Chuman H, Matsuda F, Yamashiro K, Gotoh N, Miyake M, Astakhov S, Osman E, Al-Obeidan S, Owaidhah O, Al-Jasim L, Shahwan SA, Fogarty R, Leo P, Yetkin Y, Oğuz Ç, Kanavi MR, Beni AN, Yazdani S, Akopov E, Toh KY, Howell G, Orr A, Goh Y, Meah WY, Peh SQ, Kosior-Jarecka E, Lukasik U, Krumbiegel M, Vithana E, Wong TY, Liu Y, Koch AA, Challa P, Rautenbach R, Mackey D, Hewitt A, Mitchell P, Wang JJ, Ziskind A, Carmichael T, Ramakrishnan R, Narendran K, Venkatesh R, Vijayan S, Zhao P, Chen X, Guadarrama-Vallejo D, Cheng CY, Perera S, Husain R, Ho SL, Welge-Luessen UC, Mardin C, Schloetzer-Schrehardt U, Hillmer A, Herms S, Moebus S, Nöthen M, Weisschuh N, Shetty R, Ghosh A, Teo YY, Brown M, Lischinsky I, Blue Mountains Eye Study GWAS Team, Wellcome Trust Case Control Consortium 2, Crowston J, Coote M, Zhao B, Sang J, Zhang N, You Q, Vysochinskaya V, Founti P, Chatzikyriakidou A, Lambropoulos A, Anastasopoulos E, Coleman A, Wilson R, Rhee D, Kang JH, May-Bolchakova I, Heegaard S, Mori K, Alward W, Jonas J, Xu L, Liebmann J, Chowbay B, Schaeffeler E, Schwab M, Lerner F, Wang N, Yang Z, Frezzotti P, Kinoshita S, Fingert J, Inatani M, Tashiro K, Reis A, Edward D, Pasquale L, Kubota T, Wiggs J, Pasutto F, Topouzis F, Dubina M, Craig J, Yoshimura N, Sundaresan P, John S, Ritch R, Hauser M, Khor CC. A common variant mapping to CACNA1A is associated with susceptibility to exfoliation syndrome.. Nat Genet. 2015;47(4):387–92.

Exfoliation syndrome (XFS) is the most common recognizable cause of open-angle glaucoma worldwide. To better understand the etiology of XFS, we conducted a genome-wide association study (GWAS) of 1,484 cases and 1,188 controls from Japan and followed up the most significant findings in a further 6,901 cases and 20,727 controls from 17 countries across 6 continents. We discovered a genome-wide significant association between a new locus (CACNA1A rs4926244) and increased susceptibility to XFS (odds ratio (OR) = 1.16, P = 3.36 × 10(-11)). Although we also confirmed overwhelming association at the LOXL1 locus, the key SNP marker (LOXL1 rs4886776) demonstrated allelic reversal depending on the ancestry group (Japanese: ORA allele = 9.87, P = 2.13 × 10(-217); non-Japanese: ORA allele = 0.49, P = 2.35 × 10(-31)). Our findings represent the first genetic locus outside of LOXL1 surpassing genome-wide significance for XFS and provide insight into the biology and pathogenesis of the disease.

Bunker S, Holeniewska J, Vijay S, Dahlmann-Noor A, Khaw P, Ng YS, Shima D, Foxton R. Experimental glaucoma induced by ocular injection of magnetic microspheres.. J Vis Exp. 2015;(96).

Progress in understanding the pathophysiology, and providing novel treatments for glaucoma is dependent on good animal models of the disease. We present here a protocol for elevating intraocular pressure (IOP) in the rat, by injecting magnetic microspheres into the anterior chamber of the eye. The use of magnetic particles allows the user to manipulate the beads into the iridocorneal angle, thus providing a very effective blockade of fluid outflow from the trabecular meshwork. This leads to long-lasting IOP rises, and eventually neuronal death in the ganglion cell layer (GCL) as well as optic nerve pathology, as seen in patients with the disease. This method is simple to perform, as it does not require machinery, specialist surgical skills, or many hours of practice to perfect. Furthermore, the pressure elevations are very robust, and reinjection of the magnetic microspheres is not usually required unlike in some other models using plastic beads. Additionally, we believe this method is suitable for adaptation for the mouse eye.

Jakobiec F, Kool M, Stagner A, Pfister S, Eagle R, Proia A, Korshunov A. Intraocular Medulloepitheliomas and Embryonal Tumors with Multilayered Rosettes of the Brain: Comparative Roles of LIN28A and C19MC.. Am J Ophthalmol. 2015;

PURPOSE: To compare immunohistochemical and genetic overlaps and differences between intraocular medulloepitheliomas and embryonal tumors with multilayered rosettes of the brain. DESIGN: Retrospective histopathologic, immunohistochemical and genetic analysis of 20 intraocular medulloepitheliomas. METHODS: 1) Review of clinical data and hematoxylin and eosin stained sections with 2) immunohistochemical staining of paraffin sections using a polyclonal antibody against the protein LIN28A, and 3) FISH testing for the amplification of the genetic locus 19q13.42 involving the C19MC cluster of miRNA. Ten retinoblastomas served as controls and to determine the specificity of these biomarkers for intraocular medulloepitheliomas. RESULTS: Nineteen of the 20 intraocular medulloepitheliomas were either diffusely or focally LIN28A positive (weak, moderate or strong). The most intense positivity correlated with aggressive behavior such as intraocular tissue invasion or extraocular extension. None of the cases studied by fluorescence in situ hybridization (FISH) harbored an amplicon for C19MC. The ten retinoblastomas were LIN28A and C19MC negative. CONCLUSION: LIN28A has a putative role in oncogenesis and is found only in embryonic cells and malignancies. Intraocular medulloepitheliomas and embryonal tumors with multilayered rosettes of the brain both display LIN28A positivity. Only the latter, however, display amplification of the 19q13.42 locus involving C19MC, implying that other causative factors are at play in intraocular medulloepitheliomas. More aggressive tumor behavior within the eye can be partially predicted by LIN28A staining intensity.

Lei H, Qian C, Lei J, Haddock L, Mukai S, Kazlauskas A. RasGAP Promotes Autophagy and Thereby Suppresses Platelet-Derived Growth Factor Receptor-Mediated Signaling Events, Cellular Responses, and Pathology.. Mol Cell Biol. 2015;35(10):1673–85.
Platelet-derived growth factors (PDGFs) and their receptors (PDGFRs) make profound contributions to both physiology and pathology. While it is widely believed that direct (PDGF-mediated) activation is the primary mode of activating PDGFRs, the discovery that they can also be activated indirectly begs the question of the relevance of the indirect mode of activating PDGFRs. In the context of a blinding eye disease, indirect activation of PDGFRα results in persistent signaling, which suppresses the level of p53 and thereby promotes viability of cells that drive pathogenesis. Under the same conditions, PDGFRβ fails to undergo indirect activation. In this paper, we report that RasGAP (GTPase-activating protein of Ras) prevented indirect activation of PDGFRβ. RasGAP, which associates with PDGFRβ but not PDGFRα, reduced the level of mitochondrion-derived reactive oxygen species, which are required for enduring activation of PDGFRs. Furthermore, preventing PDGFRβ from associating with RasGAP allowed it to signal enduringly and drive pathogenesis of a blinding eye disease. These results indicate a previously unappreciated role of RasGAP in antagonizing indirect activation of PDGFRβ, define the underlying mechanism, and raise the possibility that PDGFRβ-mediated diseases involve indirect activation of PDGFRβ.
Liu Y, Kam W, Ding J, Sullivan D. Can tetracycline antibiotics duplicate the ability of azithromycin to stimulate human meibomian gland epithelial cell differentiation?. Cornea. 2015;34(3):342–6.

PURPOSE: Azithromycin and tetracyclines are commonly prescribed in the United States for the treatment of meibomian gland dysfunction (MGD). The efficacy of these antibiotics has been believed to be their antiinflammatory and antibacterial actions, which suppress MGD-associated posterior blepharitis and growth of lid bacteria. However, we recently discovered that azithromycin can act directly on human meibomian gland epithelial cells (HMGECs) to stimulate their function. In this study, we sought to determine whether tetracycline antibiotics can duplicate this azithromycin effect. METHODS: Immortalized HMGEC were cultured in the presence of a vehicle, azithromycin, doxycycline, minocycline, or tetracycline for 5 days. Cells were evaluated for cholesterol and neutral lipid staining, and the lipid composition of cellular lysates was analyzed by high-performance thin-layer chromatography. RESULTS: Our results demonstrate that azithromycin's ability to stimulate the differentiation of human meibomian gland cells is unique, and is not duplicated by doxycycline, minocycline, or tetracycline. Azithromycin, but not the other antibiotics, significantly increased the cellular accumulation of cholesterol, cholesterol esters, phospholipids, and lysosomes. These differentiative actions of azithromycin were paralleled by an increased expression of sterol regulatory element-binding protein 1. CONCLUSIONS: Our findings show that the stimulatory effects of azithromycin on HMGEC function are unique and are not duplicated by the antibiotics doxycycline, minocycline, or tetracycline. Our results further suggest that this stimulatory influence of azithromycin may contribute to its beneficial effect in treating MGD and its associated evaporative dry eye disease.