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Item Comparison of Intraocular Pressure, Blood Pressure, Ocular Perfusion Pressure and Blood Flow Fluctuations During Dorzolamide Versus Timolol Add-On Therapy in Prostaglandin Analogue Treated Glaucoma Subjects(MDPI, 2012-03-21) Januleviciene, Ingrida; Siaudvytyte, Lina; Diliene, Vaida; Barsauskaite, Ruta; Paulaviciute-Baikstiene, Daiva; Siesky, Brent; Harris, Alon; Ophthalmology, School of MedicineObjective: To compare the effects of dorzolamide and timolol add-on therapy in open-angle glaucoma (OAG) patients previously treated with prostaglandin analogue (Pg), by evaluating fluctuations in the intraocular (IOP), blood (BP), ocular perfusion pressures (OPP) and retrobulbar blood flow (RBF) parameters. Methods: 35 OAG patients (35 eyes), 31 women (88.6%) age 63.3 (8.9) years were evaluated in a 3 month randomized, cross-over, single-masked study. During the experiments BP, heart rate, IOP and OPP were assessed 4 times per day (8-12-16-20 h). RBF was measured twice per day (8-20 h) using Color Doppler imaging in the ophthalmic (OA), central retinal (CRA), nasal (nSPCA) and temporal (tSPCA) posterior ciliary arteries. In each vessel, peak systolic velocity (PSV) and end-diastolic velocity (EDV) were assessed and vascular resistance (RI) calculated. Results: Both add-on therapies lowered IOP in a statistically significant manner from 15.7 ± 2.4 mmHg at latanoprost baseline to 14.9 ± 2.2 mmHg using dorzolamide (p < 0.001) and 14.2 ± 1.9 mmHg using timolol (p < 0.001). The IOP lowering effect was statistically significant at 20 h, favoring timolol as compared to dorzolamide (1.4 ± 2.4 vs. 0.2 ± 2.1 mmHg), (p < 0.05). Dorzolamide add-on therapy showed smaller IOP (2.0 ± 1.4), SPP (13.3 ± 7.9), systolic BP (13.5 ± 8.7) and diastolic BP (8.4 ± 5.4) fluctuations as compared to both latanoprost baseline or timolol add-on therapies. Higher difference between morning and evening BP was correlated to decreased evening CRA EDV in the timolol group (c = -0.41; p = 0.01). With increased MAP in the morning or evening hours, we found increased evening OA RI in timolol add-on group (c = 0.400, p = 0.02; c = 0.513, p = 0.002 accordingly). Higher MAP fluctuations were related to impaired RBF parameters during evening hours-decreased CRA EDV (c = -0.408; p = 0.01), increased CRA RI (c = 0.576; p < 0.001) and tSPCA RI (c = 0.356; p = 0.04) in the dorzolamide group and increased nSPCA RI (c = 0.351; p = 0.04) in the timolol add-on group. OPP fluctuations correlated with increased nSPCA RI (c = 0.453; p = 0.006) in the timolol group. OPP fluctuations were not related to IOP fluctuations in both add-on therapies (p < 0.05). Conclusions: Both dorzolamide and timolol add-on therapies lowered IOP in a statistically significant fashion dorzolamide add-on therapy showed lower fluctuations in IOP, SPP and BP. Higher variability of daytime OPP led to impaired RBF parameters in the evening.Item Plasticity of visual attention in Isha yoga meditation practitioners before and after a 3-month retreat(Frontiers Media, 2013-12-12) Braboszcz, Claire; Cahn, B. Rael; Balakrishnan, Bhavani; Maturi, Raj K.; Grandchamp, Romain; Delorme, Arnaud; Ophthalmology, School of MedicineMeditation has lately received considerable interest from cognitive neuroscience. Studies suggest that daily meditation leads to long lasting attentional and neuronal plasticity. We present changes related to the attentional systems before and after a 3 month intensive meditation retreat. We used three behavioral psychophysical tests - a Stroop task, an attentional blink task, and a global-local letter task-to assess the effect of Isha yoga meditation on attentional resource allocation. 82 Isha yoga practitioners were tested at the beginning and at the end of the retreat. Our results showed an increase in correct responses specific to incongruent stimuli in the Stroop task. Congruently, a positive correlation between previous meditation experience and accuracy to incongruent Stroop stimuli was also observed at baseline. We also observed a reduction of the attentional blink. Unexpectedly, a negative correlation between previous meditation experience and attentional blink performance at baseline was observed. Regarding spatial attention orientation as assessed using the global-local letter task, participants showed a bias toward local processing. Only slight differences in performance were found pre- vs. post- meditation retreat. Biasing toward the local stimuli in the global-local task and negative correlation of previous meditation experience with attentional blink performance is consistent with Isha practices being focused-attention practices. Given the relatively small effect sizes and the absence of a control group, our results do not allow clear support nor rejection of the hypothesis of meditation-driven neuronal plasticity in the attentional system for Isha yoga practice.Item Regenerative Therapeutic Potential of Adipose Stromal Cells in Early Stage Diabetic Retinopathy(Public Library of Science, 2014-01-09) Rajashekhar, Gangaraju; Ramadan, Ahmed; Abburi, Chandrika; Callaghan, Breedge; Traktuev, Dmitry O.; Evans-Molina, Carmella; Maturi, Raj; Harris, Alon; Kern, Timothy S.; March, Keith L.; Ophthalmology, School of MedicineDiabetic retinopathy (DR) is the leading cause of blindness in working-age adults. Early stage DR involves inflammation, vascular leakage, apoptosis of vascular cells and neurodegeneration. In this study, we hypothesized that cells derived from the stromal fraction of adipose tissue (ASC) could therapeutically rescue early stage DR features. Streptozotocin (STZ) induced diabetic athymic nude rats received single intravitreal injection of human ASC into one eye and saline into the other eye. Two months post onset of diabetes, administration of ASC significantly improved "b" wave amplitude (as measured by electroretinogram) within 1-3 weeks of injection compared to saline treated diabetic eyes. Subsequently, retinal histopathological evaluation revealed a significant decrease in vascular leakage and apoptotic cells around the retinal vessels in the diabetic eyes that received ASC compared to the eyes that received saline injection. In addition, molecular analyses have shown down-regulation in inflammatory gene expression in diabetic retina that received ASC compared to eyes that received saline. Interestingly, ASC were found to be localized near retinal vessels at higher densities than seen in age matched non-diabetic retina that received ASC. In vitro, ASC displayed sustained proliferation and decreased apoptosis under hyperglycemic stress. In addition, ASC in co-culture with retinal endothelial cells enhance endothelial survival and collaborate to form vascular networks. Taken together, our findings suggest that ASC are able to rescue the neural retina from hyperglycemia-induced degeneration, resulting in importantly improved visual function. Our pre-clinical studies support the translational development of adipose stem cell-based therapy for DR to address both retinal capillary and neurodegeneration.Item Characterization, Enrichment, and Computational Modeling of Cross-Linked Actin Networks in Transformed Trabecular Meshwork Cells(Association for Research in Vision and Ophthalmology, 2025) Li, Haiyan; Harvey, Devon H.; Dai, Jiannong; Swingle, Steven P.; Compton, Anthony M.; Sugali, Chenna Kesavulu; Dhamodaran, Kamesh; Yao, Jing; Lin, Tsai-Yu; Sulchek, Todd; Kim, Taeyoon; Ethier, C. Ross; Mao, Weiming; Ophthalmology, School of MedicinePurpose: Cross-linked actin networks (CLANs) are prevalent in the glaucomatous trabecular meshwork (TM). We previously developed the GTM3L cell line, which spontaneously forms fluorescently labeled CLANs, by transducing GTM3, a transformed glaucomatous TM cell line, with a lentivirus expressing the LifeAct-GFP fusion protein. Here, we determined if LifeAct-GFP viral copy numbers are associated with CLANs, developed approaches to increase CLAN incidence, and computationally studied the biomechanical properties of CLAN-containing GTM3L cells. Methods: GTM3L cells were fluorescently sorted for viral copy number analysis to determine whether increased CLAN incidence was associated with copy number. CLAN incidence was increased by combining (1) differential adhesion sorting, (2) cell deswelling, and (3) cell stiffness selection. GTM3L cells were cultured on glass or soft hydrogels for stiffness measurement by atomic force microscopy. Computational models studied the biomechanical properties of CLANs. Results: GTM3L cells had one LifeAct-GFP viral copy/cell on average, and viral copy number or LifeAct-GFP expression level did not associate with CLAN incidence rate. However, CLAN rate was increased from -0.28% to -50% by combining the three enrichment methods noted above. Further, GTM3L cells formed more CLANs on a stiff versus a soft substrate. Computational modeling predicted that CLANs contribute to higher cell stiffness, including increased resistance of the nucleus to tensile stress when CLANs are physically linked to the nucleus. Conclusions: It is possible to greatly enhance CLAN incidence in GTM3L cells. CLANs are mechanosensitive structures that affect cell biomechanical properties. Further research is needed to determine the biomechanics, mechanobiology, and etiology of CLANs in the TM.Item Vasoreparative Dysfunction of CD34+ Cells in Diabetic Individuals Involves Hypoxic Desensitization and Impaired Autocrine/Paracrine Mechanisms(Public Library of Science, 2014-04-08) Jarajapu, Yagna P. R.; Hazra, Sugata; Segal, Mark; LiCalzi, Sergio; Jhadao, Chandra; Qian, Kevin; Mitter, Sayak K.; Raizada, Mohan K.; Boulton, Michael E.; Grant, Maria B.; Ophthalmology, School of MedicineWe hypothesized that endothelial progenitor cells derived from individuals with diabetes would exhibit functional defects including inability to respond to hypoxia and altered paracrine/autocrine function that would impair the angiogenic potential of these cells. Circulating mononuclear cells isolated from diabetic (n = 69) and nondiabetic (n = 46) individuals were used to grow endothelial colony forming cells (ECFC), early endothelial progenitor cells (eEPCs) and isolate CD34+ cells. ECFCs and eEPCs were established from only 15% of the diabetic individuals tested thus directing our main effort toward examination of CD34+ cells. CD34+ cells were plated in basal medium to obtain cell-free conditioned medium (CM). In CM derived from CD34+ cells of diabetic individuals (diabetic-CM), the levels of stem cell factor, hepatocyte growth factor, and thrombopoietin were lower, and IL-1β and tumor necrosis factor (TNFα) levels were higher than CM derived from nondiabetic individuals (nondiabetic-CM). Hypoxia did not upregulate HIF1α in CD34+ cells of diabetic origin. Migration and proliferation of nondiabetic CD34+ cells toward diabetic-CM were lower compared to nondiabetic-CM. Attenuation of pressure-induced constriction, potentiation of bradykinin relaxation, and generation of cGMP and cAMP in arterioles were observed with nondiabetic-CM, but not with diabetic-CM. Diabetic-CM failed to induce endothelial tube formation from vascular tissue. These results suggest that diabetic subjects with microvascular complications exhibit severely limited capacity to generate ex-vivo expanded endothelial progenitor populations and that the vasoreparative dysfunction observed in diabetic CD34+ cells is due to impaired autocrine/paracrine function and reduced sensitivity to hypoxia.Item Transcriptional and Epigenetic Regulation of KIF14 Overexpression in Ovarian Cancer(Public Library of Science, 2014-03-13) Thériault, Brigitte L.; Basavarajappa, Halesha D.; Lim, Harvey; Pajovic, Sanja; Gallie, Brenda L.; Corson, Timothy W.; Ophthalmology, School of MedicineKIF14 (kinesin family member 14) is a mitotic kinesin and an important oncogene in several cancers. Tumor KIF14 expression levels are independently predictive of poor outcome, and in cancer cells KIF14 can modulate metastatic behavior by maintaining appropriate levels of cell adhesion and migration proteins at the cell membrane. Thus KIF14 is an exciting potential therapeutic target. Understanding KIF14's regulation in cancer cells is crucial to the development of effective and selective therapies to block its tumorigenic function(s). We previously determined that close to 30% of serous ovarian cancers (OvCa tumors) exhibit low-level genomic gain, indicating one mechanism of KIF14 overexpression in tumors. We now report on transcriptional and epigenetic regulation of KIF14. Through promoter deletion analyses, we identified one cis-regulatory region containing binding sites for Sp1, HSF1 and YY1. siRNA-mediated knockdown of these transcription factors demonstrated endogenous regulation of KIF14 overexpression by Sp1 and YY1, but not HSF1. ChIP experiments confirmed an enrichment of both Sp1 and YY1 binding to the endogenous KIF14 promoter in OvCa cell lines with high KIF14 expression. A strong correlation was seen in primary serous OvCa tumors between Sp1, YY1 and KIF14 expression, further evidence that these transcription factors are important players in KIF14 overexpression. Hypomethylation patterns were observed in primary serous OvCa tumors, suggesting a minor role for promoter methylation in the control of KIF14 gene expression. miRNA expression analysis determined that miR-93, miR-144 and miR-382 had significantly lower levels of expression in primary serous OvCa tumors than normal tissues; treatment of an OvCa cell line with miRNA mimics and inhibitors specifically modulated KIF14 mRNA levels, pointing to potential novel mechanisms of KIF14 overexpression in primary tumors. Our findings reveal multiple mechanisms of KIF14 upregulation in cancer cells, offering new targets for therapeutic interventions to reduce KIF14 in tumors, aiming at improved prognosis.Item Mesenchymal Stem Cells: New Players in Retinopathy Therapy(Frontiers Media, 2014-04-24) Rajashekhar, Gangaraju; Ophthalmology, School of MedicineRetinopathies in human and animal models have shown to occur through loss of pericytes resulting in edema formation, excessive immature retinal angiogenesis, and neuronal apoptosis eventually leading to blindness. In recent years, the concept of regenerating terminally differentiated organs with a cell-based therapy has evolved. The cells used in these approaches are diverse and include tissue-specific endogenous stem cells, endothelial progenitor (EPC), embryonic stem cells, induced pluripotent stem cells (iPSC) and mesenchymal stem cells (MSC). Recently, MSC derived from the stromal fraction of adipose tissue have been shown to possess pluripotent differentiation potential in vitro. These adipose stromal cells (ASC) have been differentiated in a number of laboratories to osteogenic, myogenic, vascular, and adipocytic cell phenotypes. In vivo, ASC have been shown to have functional and phenotypic overlap with pericytes lining microvessels in adipose tissues. Furthermore, these cells either in paracrine mode or physical proximity with endothelial cells, promoted angiogenesis, improved ischemia-reperfusion, protected from myocardial infarction, and were neuroprotective. Owing to the easy isolation procedure and abundant supply, fat-derived ASC are a more preferred source of autologous mesenchymal cells compared to bone marrow MSC. In this review, we present evidence that these readily available ASC from minimally invasive liposuction will facilitate translation of ASC research into patients with retinal diseases in the near future.Item KIF14 Promotes AKT Phosphorylation and Contributes to Chemoresistance in Triple-Negative Breast Cancer(Elsevier, 2014) Singel, Stina M.; Cornelius, Crystal; Zaganjor, Elma; Batten, Kimberly; Sarode, Venetia R.; Buckley, Dennis L.; Peng, Yan; John, George B.; Li, Hsiao C.; Sadeghi, Navid; Wright, Woodring E.; Lum, Lawrence; Corson, Timothy W.; Shay, Jerry W.; Ophthalmology, School of MedicineDespite evidence that kinesin family member 14 (KIF14) can serve as a prognostic biomarker in various solid tumors, how it contributes to tumorigenesis remains unclear. We observed that experimental decrease in KIF14 expression increases docetaxel chemosensitivity in estrogen receptor-negative/progesterone receptor-negative/human epidermal growth factor receptor 2-negative, "triple-negative" breast cancers (TNBC). To investigate the oncogenic role of KIF14, we used noncancerous human mammary epithelial cells and ectopically expressed KIF14 and found increased proliferative capacity, increased anchorage-independent grown in vitro, and increased resistance to docetaxel but not to doxorubicin, carboplatin, or gemcitabine. Seventeen benign breast biopsies of BRCA1 or BRCA2 mutation carriers showed increased KIF14 mRNA expression by fluorescence in situ hybridization compared to controls with no known mutations in BRCA1 or BRCA2, suggesting increased KIF14 expression as a biomarker of high-risk breast tissue. Evaluation of 34 cases of locally advanced TNBC showed that KIF14 expression significantly correlates with chemotherapy-resistant breast cancer. KIF14 knockdown also correlates with decreased AKT phosphorylation and activity. Live-cell imaging confirmed an insulin-induced temporal colocalization of KIF14 and AKT at the plasma membrane, suggesting a potential role of KIF14 in promoting activation of AKT. An experimental small-molecule inhibitor of KIF14 was then used to evaluate the potential anticancer benefits of downregulating KIF14 activity. Inhibition of KIF14 shows a chemosensitizing effect and correlates with decreasing activation of AKT. Together, these findings show an early and critical role for KIF14 in the tumorigenic potential of TNBC, and therapeutic targeting of KIF14 is feasible and effective for TNBC.Item The Difference in Translaminar Pressure Gradient and Neuroretinal Rim Area in Glaucoma and Healthy Subjects(Hindawi, 2014) Siaudvytyte, Lina; Januleviciene, Ingrida; Ragauskas, Arminas; Bartusis, Laimonas; Meiliuniene, Indre; Siesky, Brent; Harris, Alon; Ophthalmology, School of MedicinePurpose: To assess differences in translaminar pressure gradient (TPG) and neuroretinal rim area (NRA) in patients with normal tension glaucoma (NTG), high tension glaucoma (HTG), and healthy controls. Methods: 27 patients with NTG, HTG, and healthy controls were included in the prospective pilot study (each group consisted of 9 patients). Intraocular pressure (IOP), intracranial pressure (ICP), and confocal laser scanning tomography were assessed. TPG was calculated as the difference of IOP minus ICP. ICP was measured using noninvasive two-depth transcranial Doppler device. The level of significance P < 0.05 was considered significant. Results: NTG patients had significantly lower IOP (13.7(1.6) mmHg), NRA (0.97(0.36) mm(2)), comparing with HTG and healthy subjects, P < 0.05. ICP was lower in NTG (7.4(2.7) mmHg), compared with HTG (8.9(1.9) mmHg) and healthy subjects (10.5(3.0) mmHg); however, the difference between groups was not statistically significant (P > 0.05). The difference between TPG for healthy (5.4(7.7) mmHg) and glaucomatous eyes (NTG 6.3(3.1) mmHg, HTG 15.7(7.7) mmHg) was statistically significant (P < 0.001). Higher TPG was correlated with decreased NRA (r = -0.83; P = 0.01) in the NTG group. Conclusion: Translaminar pressure gradient was higher in glaucoma patients. Reduction of NRA was related to higher TPG in NTG patients. Further prospective studies are warranted to investigate the involvement of TPG in glaucoma management.Item A 6-month, subject-masked, randomized controlled study to assess efficacy of dexamethasone as an adjunct to bevacizumab compared with bevacizumab alone in the treatment of patients with macular edema due to central or branch retinal vein occlusion(Dove Press, 2014-06-03) Maturi, Raj K.; Chen, Vincent; Raghinaru, Dan; Bleau, Laurie; Stewart, Michael W.; Ophthalmology, School of MedicineAims: To determine if intravitreal bevacizumab combined with the dexamethasone intravitreal implant 0.7 mg improves visual acuity and macular thickness more than bevacizumab monotherapy in eyes with macular edema due to branch and central retinal vein occlusions. Methods: Thirty eyes were randomly assigned to receive either combination therapy or bevacizumab monotherapy. All patients received intravitreal bevacizumab at baseline, followed by dexamethasone implants or sham injections 1 week later. Monthly bevacizumab injections were given if the central subfield thickness (CST) was >250 μm, and the combined group received a second implant at month 4 or 5 if CST was >250 μm. Results: At 6 months, several secondary endpoints were met. Patients receiving combined therapy required fewer bevacizumab reinjections compared to those receiving monotherapy (two versus three; P=0.02), experienced greater mean reductions in CST from randomization (-56 μm versus +45 μm; P=0.01), and were more likely to have resolved all edema (CST <250 μm) (7/11 versus 2/14; P=0.02). The primary endpoint was not met since mean visual acuity changes from baseline were similar in the two groups (P=0.75). Conclusion: In patients with macular edema due to vein occlusions, bevacizumab with dexamethasone implants produces greater improvements in macular thickness compared to bevacizumab monotherapy, despite fewer bevacizumab injections.