Transport of the Proinflammatory Chemokines C-C Motif Chemokine Ligand 2 (MCP-1) and C-C Motif Chemokine Ligand 5 (RANTES) across the Intact Mouse Blood-Brain Barrier Is Inhibited by Heparin and Eprodisate and Increased with Systemic Inflammation.

One important function of the vascular blood-brain barrier (BBB) is to facilitate neuroimmune communication. The BBB fulfills this function, in part, through its ability to transport cytokines and chemokines. C-C motif chemokine receptor 2 (CCL2) (MCP-1) and C-C motif chemokine receptor 5 (CCL5) (RANTES) are proinflammatory chemokines that mediate neuroimmune responses to acute insults and aspects of brain injury and neurodegenerative diseases; however, a blood-to-brain transport system has not been evaluated for either chemokine in vivo. Therefore, we determined whether CCL2 and CCL5 in blood can cross the intact BBB and enter the brain. Using CD-1 mice, we found that 125I-labeled CCL2 and CCL5 crossed the BBB and entered the brain parenchyma. We next aimed to identify the mechanisms of 125I-CCL2 and 125I-CCL5 transport in an in situ brain perfusion model. We found that both heparin and eprodisate inhibited brain uptake of 125I-CCL2 and 125I-CCL5 in situ, whereas antagonists of their receptors, CCR2 or CCR5, respectively, did not, suggesting that heparan sulfates at the endothelial surface mediate BBB transport. Finally, we showed that CCL2 and CCL5 transport across the BBB increased following a single injection of 0.3 mg/kg lipopolysaccharide. These data demonstrate that CCL2 and CCL5 in the brain can derive, in part, from the circulation, especially during systemic inflammation. Further, binding to the BBB-associated heparan sulfate is a mechanism by which both chemokines can cross the intact BBB, highlighting a novel therapeutic target for treating neuroinflammation. SIGNIFICANCE STATEMENT: Our work demonstrates that C-C motif chemokine ligand 2 (CCL2) and C-C motif chemokine ligand 5 (CCL5) can cross the intact blood-brain barrier and that transport is robustly increased during inflammation. These data suggest that circulating CCL2 and CCL5 can contribute to brain levels of each chemokine. We further show that the transport of both chemokines is inhibited by heparin and eprodisate, suggesting that CCL2/CCL5-heparan sulfate interactions could be therapeutically targeted to limit accumulation of these chemokines in the brain.

QUANTIFIED ANASTOMOTIC AREAS OF NEOVASCULARIZATION AS FACTORS ASSOCIATED WITH FREQUENT RECURRENCE IN NEOVASCULAR AGE-RELATED MACULAR DEGENERATION.

PURPOSE: To investigate the quantitative characteristics of anastomoses of macular neovascularization (MNV) in neovascular age-related macular degeneration using optical coherence tomography angiography according to the frequency of intravitreal injections. METHODS: Eighty-six eyes of 86 patients treated for neovascular age-related macular degeneration were classified into two groups based on the number of intravitreal injections administered over 12 months: stable (<3) and unstable (≥3). Anastomotic areas were defined as areas surrounded by neighboring vessels in the MNV; their total number, mean area, maximal and minimal diameters (i.e., maximal and minimum Feret diameters), and ratio (Feret aspect ratio) were analyzed in the inner and outer areas of the MNV. RESULTS: Forty-four and 42 eyes were classified into the stable and unstable groups, respectively. The eyes in the unstable group had larger anastomotic areas with longer minimum Feret diameters and longer perimeters in the outer MNV. In the logistic regression analysis, instability was associated with a larger anastomotic area and a longer minimum Feret diameter in the outer MNV. Multivariate analysis revealed that a longer minimum Feret diameter in the outer MNV was the most significant factor ( P = 0.03). CONCLUSION: The quantitative characteristics of the anastomotic areas in the MNV might indicate the need for intravitreal injections in patients with neovascular age-related macular degeneration.

Applying Reinforcement Learning for Enhanced Cybersecurity against Adversarial Simulation.

Cybersecurity is a growing concern in today's interconnected world. Traditional cybersecurity approaches, such as signature-based detection and rule-based firewalls, are often limited in their ability to effectively respond to evolving and sophisticated cyber threats. Reinforcement learning (RL) has shown great potential in solving complex decision-making problems in various domains, including cybersecurity. However, there are significant challenges to overcome, such as the lack of sufficient training data and the difficulty of modeling complex and dynamic attack scenarios hindering researchers' ability to address real-world challenges and advance the state of the art in RL cyber applications. In this work, we applied a deep RL (DRL) framework in adversarial cyber-attack simulation to enhance cybersecurity. Our framework uses an agent-based model to continuously learn from and adapt to the dynamic and uncertain environment of network security. The agent decides on the optimal attack actions to take based on the state of the network and the rewards it receives for its decisions. Our experiments on synthetic network security show that the DRL approach outperforms existing methods in terms of learning optimal attack actions. Our framework represents a promising step towards the development of more effective and dynamic cybersecurity solutions.

Network differences based on arterial spin labeling related to anti-seizure medication response in focal epilepsy.

PURPOSE: The aim of this study was to determine whether anti-seizure medication (ASM) response is associated with structural connectivity in diffusion tensor imaging (DTI) or functional co-variance network in arterial spin labeling (ASL) magnetic resonance imaging (MRI) in patients with focal epilepsy. METHODS: In this retrospective study conducted at a tertiary hospital, we enrolled 105 patients with focal epilepsy, of which 64 patients were good ASM responders, and 41 patients were poor ASM responders. All patients showed normal MRI findings on visual inspection and underwent DTI and ASL MRI from August 2018 to July 2020, with regular follow-up for at least 12 months after epilepsy diagnosis while taking ASMs. We calculated the structural connectivity based on DTI and functional co-variance network based on ASL MRI by using graph theory and analyzed their differences in relation to the ASM response. RESULTS: No differences were observed in structural connectivity between the good and poor ASM responders. However, significant differences were observed in functional co-variance network between the good and poor ASM responders. In comparison with good ASM responders, poor ASM responders showed a significantly greater characteristic path length (2.557 vs. 1.753, p = 0.034) and a lower local efficiency (2.311 vs. 3.927, p = 0.048). CONCLUSION: Significant differences were observed in functional co-variance network based on ASL MRI between the good and poor ASM responders. These findings suggest that functional co-variance network could serve as a new biomarker of ASM response in focal epilepsy.

Alterations in the structural covariance network of the hypothalamus in patients with narcolepsy.

PURPOSE: The hypothalamus plays a pivotal role in the pathogenesis of narcolepsy. This study aimed to evaluate the differences in the structural covariance network of thehypothalamus based on volume differences between patients with narcolepsy and healthy controls. METHODS: We retrospectively enrolled 15 patients with narcolepsy and 19 healthy controls.All subjects underwent three-dimensional T1-weighted imaging using a 3-T magnetic resonance imaging scanner. Hypothalamic subunits were segmented, and the volumes of individual hypothalamic subunits were obtained using the FreeSurfer program. Subsequently, we conducted a structural covariance network analysis of the subunit volumes with graph theory using the BRAPH program in patients with narcolepsy and in healthy controls. RESULTS: There were no significant differences in the volumes of the entire right and left hypothalamus nor in the hypothalamic subunit between patients with narcolepsy and healthy controls. However, we found significant differences in the structural covariance network in the hypothalamus between these groups. The characteristic path length was significantly lower in patients with narcolepsy than in healthy controls (1.698 vs. 2.831, p = 0.001). However, other network measures did not differ between patients with narcolepsy and healthy controls. CONCLUSION: We found that the structural covariance network of the hypothalamus, as assessed from the subunit volumes of hypothalamic regions using a graph theoretical analysis, is different in patients with narcolepsy compared to healthy controls. These findings may contribute to the understanding of the pathogenesis of narcolepsy.

Application of machine learning analysis based on diffusion tensor imaging to identify REM sleep behavior disorder.

PURPOSE: We evaluated the feasibility of machine learning analysis using diffusion tensor imaging (DTI) parameters to identify patients with idiopathic rapid eye movement (REM) sleep behavior disorder (RBD). We hypothesized that patients with idiopathic RBD could be identified via machine learning analysis based on DTI. METHODS: We enrolled 20 patients with newly diagnosed idiopathic RBD at a tertiary hospital. We also included 20 healthy subjects as a control group. All of the subjects underwent DTI. We obtained the conventional DTI parameters and structural connectomic profiles from the DTI. We investigated the differences in conventional DTI measures and structural connectomic profiles between patients with idiopathic RBD and healthy controls. We then used machine learning analysis using a support vector machine (SVM) algorithm to identify patients with idiopathic RBD using conventional DTI and structural connectomic profiles. RESULTS: Several regions showed significant differences in conventional DTI measures and structural connectomic profiles between patients with idiopathic RBD and healthy controls. The SVM classifier based on conventional DTI measures revealed an accuracy of 87.5% and an area under the curve of 0.900 to identify patients with idiopathic RBD. Another SVM classifier based on structural connectomic profiles yielded an accuracy of 75.0% and an area under the curve of 0.833. CONCLUSION: Our findings demonstrate the feasibility of machine learning analysis based on DTI to identify patients with idiopathic RBD. The conventional DTI parameters might be more important than the structural connectomic profiles in identifying patients with idiopathic RBD.

Alterations of structural connectivity and structural co-variance network in focal cortical dysplasia.

BACKGROUND: The aim of this study was to investigate alterations in structural connectivity and structural co-variance network in patients with focal cortical dysplasia (FCD). METHODS: We enrolled 37 patients with FCD and 35 healthy controls. All subjects underwent brain MRI with the same scanner and with the same protocol, which included diffusion tensor imaging (DTI) and T1-weighted imaging. We analyzed the structural connectivity based on DTI, and structural co-variance network based on the structural volume with T1-weighted imaging. We created a connectivity matrix and obtained network measures from the matrix using the graph theory. We tested the difference in network measure between patients with FCD and healthy controls. RESULTS: In the structural connectivity analysis, we found that the local efficiency in patients with FCD was significantly lower than in healthy controls (2.390 vs. 2.578, p = 0.031). Structural co-variance network analysis revealed that the mean clustering coefficient, global efficiency, local efficiency, and transitivity were significantly decreased in patients with FCD compared to those in healthy controls (0.527 vs. 0.635, p = 0.036; 0.545 vs. 0.648, p = 0.026; 2.699 vs. 3.801, p = 0.019; 0.791 vs. 0.954, p = 0.026, respectively). CONCLUSIONS: We demonstrate that there are significant alterations in structural connectivity, based on DTI, and structural co-variance network, based on the structural volume, in patients with FCD compared to healthy controls. These findings suggest that focal lesions with FCD could affect the whole-brain network and that FCD is a network disease.

Brain networks in patients with isolated or recurrent transient global amnesia.

OBJECTIVES: The aim of this study was to investigate differences in cerebral blood flow (CBF) and functional networks between transient global amnesia (TGA) patients with a single event and those with recurrent events using arterial spin labeling (ASL) MRI. METHODS: We enrolled patients with TGA and classified them into two groups according to the number of TGA events: TGA patients with a single event and those with recurrent events. MRI scans were performed within 24 h after TGA ictal onset in all patients. We quantified CBF and analyzed the functional network based on CBF using graph theory, and determined the differences in CBF and functional networks between the groups. RESULTS: We enrolled 44 patients with TGA. Among them, 6 patients had recurrent TGA events, whereas 38 patients had a single TGA event. No regions had significantly different CBFs between TGA patients with recurrent events and those with a single event. The global functional network analysis found that the eccentricity was significantly higher in TGA patients with recurrent events than in those with a single event (5.829 vs. 4.657, p = .001). The local functional network analysis showed that several regions had significantly different betweenness centrality and eccentricity measures between TGA patients with recurrent events and those with a single event. CONCLUSIONS: We demonstrated the differences in the functional network based on CBF using graph theory according to recurrence in patients with TGA. These findings suggest that TGA is a network disease, and functional network alterations in TGA are related to clinical symptoms.

AUTOMATED QUANTIFICATION OF VITREOUS HYPERREFLECTIVE FOCI AND VITREOUS HAZE USING OPTICAL COHERENCE TOMOGRAPHY IN PATIENTS WITH UVEITIS.

PURPOSE: Development of an automated method to quantify the count of vitreous hyperreflective foci (vHF) and intensity of vitreous haze in patients with uveitis by optical coherence tomography. METHODS: A method based on deep learning to automatically segment the vHF, vitreous, and retinal pigment epithelium (RPE) in optical coherence tomography was developed using 1,058 scans from 88 optical coherence tomography volumes of 33 patients with intermediate, posterior or panuveitis. Based on segmented images, the vHF count and the relative intensity of vitreous to RPE (VIT/RPE-relative intensity) were quantified. Dice coefficient and intraclass correlation coefficient were calculated between ground truth and the trained network. RESULTS: The segmented area of vHF, vitreous, and RPE by the deep learning-based model showed good agreement with the clinicians' results, yielding a Dice coefficient of 0.69, 0.99, and 0.88, respectively. The intraclass correlation coefficient of the vHF count and the VIT/RPE-relative intensity per scan was 0.99 and 1.00, respectively. In eyes of test set, changes in vHF and VIT/RPE-relative intensity during treatment did not show similar patterns. CONCLUSION: Automated segmentation of the vHF, vitreous, and RPE in optical coherence tomography images of patients with uveitis was accomplished by a deep learning approach. The vHF count and VIT/RPE-relative intensity could be quantified with high reliability.

POST-TREATMENT PREDICTION OF OPTICAL COHERENCE TOMOGRAPHY USING A CONDITIONAL GENERATIVE ADVERSARIAL NETWORK IN AGE-RELATED MACULAR DEGENERATION.

PURPOSE: To develop a deep learning model to generate posttreatment optical coherence tomography (OCT) images of neovascular age-related macular degeneration. METHODS: Two hundred ninety-eight patients with neovascular age-related macular degeneration were included. The conditional generative adversarial network was trained using 15,183 augmented paired OCT B-scan images obtained from 723 scans of 241 patients at baseline and 1 month after 3 loading doses of an anti-vascular endothelial growth factor treatment. The network was also trained using baseline fluorescein angiography (FA) or indocyanine green angiography (ICGA) images together with baseline OCT images. A test set of 150 images of 50 eyes was used to evaluate its ability to predict the presence of intraretinal fluid, subretinal fluid, PED, and subretinal hyperreflective material. Posttreatment OCT images were compared with images generated from baseline OCT with or without FA and indocyanine green angiography images. RESULTS: The predicted images inferred from baseline OCT images achieved an acceptable accuracy, specificity, and negative predictive value for four lesions (range: 77.0-91.9, 94.1-95.1, and 54.7-96.5%, respectively). The addition of both FA and indocyanine green angiography images improved the accuracy, specificity, and negative predictive value (range: 80.7-96.3, 97.3-99.0, and 59.0-98.3%, respectively). CONCLUSION: A conditional generative adversarial network is able to generate posttreatment OCT images from baseline OCT, FA, and indocyanine green angiography images.

ASSOCIATION OF TREATMENT RESPONSE WITH QUANTITATIVE CHANGES IN CHOROIDAL NEOVASCULARIZATION AND CHOROIDAL VESSEL IN NEOVASCULAR AGE-RELATED MACULAR DEGENERATION.

PURPOSE: To evaluate the association between treatment response and quantitative morphological changes in choroidal neovascularization and outer choroidal vessels using optical coherence tomography angiography (OCTA) and en face OCT in neovascular age-related macular degeneration (nAMD). METHODS: We retrospectively analyzed 75 eyes of typical nAMD patients and 53 polypoidal choroidal vasculopathy eyes of 124 patients with OCTA performed at least 6 months after initial antivascular endothelial growth factor treatment. Quantitative parameters, including vessel area, vessel diameter, branch vessel length, fractal dimension, and lacunarity were analyzed based on en face images of the choroidal neovascularization and choroidal vessel in Haller's layer. Parameters associated with loss of logarithm of the minimum angle of resolution visual acuity with the basis of 0.3 and the treatment interval (good vs. poor responder based on 12 weeks) were analyzed. Analyses were conducted for "before OCTA" (initial visit to OCTA) and "after OCTA" (OCTA to 6 months post-OCTA). RESULTS: In typical nAMD, visual acuity loss before OCTA was associated with a higher SD of choroidal neovascularization diameter and lower choroidal fractal dimension. Visual acuity loss after OCTA in typical nAMD was associated with higher lacunarity of the choroid. Poor responders before OCTA were not associated with any factor. Poor responders after OCTA were associated with a lower SD of outer choroidal vessel diameter in typical nAMD. In polypoidal choroidal vasculopathy, no factor was associated with clinical outcomes in either period. CONCLUSION: Quantitative analyses of choroidal neovascularization on OCTA and choroidal vessels on en face OCT provide information about treatment response, including changes in visual acuity and treatment interval, in nAMD.

Diabetic macular edema with pachychoroid features.

BACKGROUND: To investigate the clinical features of diabetic macular edema (DME) in eyes with pachychoroid phenotypes using multimodal retinal imaging. METHODS: We retrospectively reviewed 210 eyes from 210 DME patients and analyzed the clinical and imaging parameters, including visual acuity, central macular thickness (CMT), subfoveal choroidal thickness (SFCT) and neural retina layer thickness (NRT). The DME eyes were divided into two groups: group 1 (80 eyes with submacular detachment [SMD]) and group 2 (130 eyes without SMD). The clinical and imaging parameters of 285 eyes from 285 diabetic patients without DME were collected as a control group. RESULTS: DME eyes with pachychoroid phenotypes were more frequent in group 1 than in group 2 (53 eyes [66.25%] and 53 eyes [40.77%], respectively, P < 0.001). Pachychoroid phenotypes were identified in 108 (37.90%) of the control eyes. CMT and NRT were greater in group 1 than in group 2. In group 1, 37 eyes had SMD combined with focal edema, and 43 eyes had SMD combined with diffuse-type edema. No significant difference in pachychoroid phenotypes was found between the focal and diffuse types (26 [70.27%] and 27 [62.79%], respectively, P = 0.481). In group 2, 70 eyes had focal-type edema, and 60 eyes had diffuse-type edema. No significant difference in the frequency of pachychoroid phenotypes was found (32 [45.71%] and 21 [35.00%], respectively, P = 0.215). Interestingly, among the 70 eyes with focal edema in group 2, 13 (40.6%) and 5 (13.2%) eyes with and without pachychoroid phenotypes showed no definite microaneurysms, respectively. CONCLUSION: SMD and focal edema without definite microaneurysms may be clinical manifestations of DME with pachychoroid phenotypes and possibly related to choroidal circulation disturbance in DME.

QUANTIFICATION OF RETINAL VESSEL TORTUOSITY IN DIABETIC RETINOPATHY USING OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY.

PURPOSE: To investigate the association of vessel tortuosity with severity of diabetic retinopathy (DR) using optical coherence tomography angiography. METHODS: We retrospectively analyzed 30 healthy eyes and 121 eyes of diabetic subjects with no DR, mild nonproliferative DR (NPDR), moderate to severe NPDR and proliferative DR (PDR). Binarized images were used to quantify the vessel tortuosity, vessel density, foveal avascular zone (FAZ) area, and FAZ acircularity. The vessels were divided vertically as superficial retinal layer and deep retinal layer, and horizontally as circular areas with 3 mm and 1.5 mm diameters. Analysis of variance was performed for multiple comparisons. Correlation analysis evaluated the association between the quantified parameters. RESULTS: Compared with healthy eyes, vessel tortuosity increased as DR severity was more in NPDR, but decreased in PDR (P = 0.033). The decrease in vessel density and the increase in both FAZ area and FAZ acircularity were consistent, while DR approached PDR. Among all parameters, statistically significant difference between no DR and mild NPDR was observed only in vessel tortuosity, especially within the 1.5 mm area of superficial retinal layer (P = 0.011). Correlations of vessel tortuosity with FAZ area and acircularity were confined to the 3 mm and 1.5 mm areas of superficial retinal layer (r = -0.185, P = 0.023 for FAZ area; r = 0.268, P = 0.001 for FAZ acircularity), while vessel density strongly correlated with FAZ parameters in the superficial retinal layer and deep retinal layer. CONCLUSION: Vessel tortuosity increased as the stage of NPDR was more severe, but decreased in PDR. The vessel tortuosity determined using optical coherence tomography angiography might be a useful parameter indicating the progression to PDR, circumventing the risk from invasive conventional angiography.

CORRELATION OF MICROVASCULAR STRUCTURES ON OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY WITH VISUAL ACUITY IN RETINAL VEIN OCCLUSION.

PURPOSE: To analyze the correlation of superficial and deep capillary plexuses using optical coherence tomography (OCT) angiography with visual acuity in eyes with retinal vein occlusion (RVO). METHODS: We retrospectively reviewed the medical records of 33 patients with retinal vein occlusion (RVO; branch retinal vein occlusion in 21 patients, central retinal vein occlusion in 12 patients) and included 33 healthy subjects as a control group, who were evaluated by OCT angiography. The OCT angiography was performed on a 3 mm × 3-mm region centered on the fovea and parafoveal area. The foveal avascular zone (FAZ), and foveal and parafoveal vascular density (VD) in superficial and deep vascular plexuses were analyzed using OCT angiography. RESULTS: The area of superficial and deep FAZ in eyes with RVO were larger than those in fellow eyes and control eyes (P = 0.034, P = 0.018). The superficial and deep parafoveal VDs in eyes with RVO were significantly lower than those in fellow eyes and control eyes (P = 0.001, P< 0.001). The area of superficial FAZ was negatively correlated with best-corrected visual acuity, and the superficial and deep parafoveal VDs were positively correlated with best-corrected visual acuity. Eighteen of the total 21 eyes with branch retinal vein occlusion (85.7%) showed a high concordance rate with respect to the location of branch retinal vein occlusion and the lowest parafoveal VD area. The multivariate analysis showed that the deep parafoveal VD was associated with best-corrected visual acuity. CONCLUSION: The OCT angiography allows to detect FAZ enlargement, increased parafoveal capillary nonperfusion, and decreased parafoveal VD in eyes with RVO. The area of superficial FAZ and the parafoveal VD are correlated with best-corrected visual acuity in eyes with RVO.

Clinical Significance of Fluid-Attenuated Inversion Recovery Vascular Hyperintensities in Borderzone Infarcts.

BACKGROUND AND PURPOSE: Fluid-attenuated inversion recovery vascular hyperintensities (FVHs) are seen in some cases with cerebral hemodynamic impairment and collateral flow. Because the worst outcomes of patients with borderzone infarcts were mainly correlated with impaired hemodynamics, the presence of FVH might provide another clue for predicting the prognosis of patients with borderzone infarcts. METHODS: We reviewed 1377 consecutive patients with ischemic stroke. Cortical borderzone (CBZ) and internal borderzone infarcts were selected based on diffusion-weighted imaging. FVHs were defined as tubular- or serpentine-shaped hyperintensities in the subarachnoid space. We investigated the clinical significance of FVHs in borderzone-infarcted patients. RESULTS: Among 87 patients with borderzone infarcts, the presence of FVH was observed in 30 (34.5%). We identified 62 patients with CBZ infarcts and 25 patients with internal borderzone infarcts. In the cases with CBZ infarcts, the initial National Institutes of Health Stroke Scale scores and the portions of nonfavorable outcome at 3 months in the FVH(+) group were significantly higher than in the FVH(-) group (P<0.05 and P<0.001, respectively). Unlike the cases with CBZ infarcts, there were no significant differences of these clinical features between the FVH(+) group and the FVH(-) group in the patients with internal borderzone infarcts. CONCLUSIONS: The findings of FVH are associated with relatively severe clinical presentation and nonfavorable prognosis in patients with CBZ infarcts, but not in patients with internal borderzone infarcts. The presence of FVH may help to identify CBZ-infarcted patients who require close observation and hemodynamic control.

BASELINE SPECTRAL DOMAIN OPTICAL COHERENCE TOMOGRAPHIC HYPERREFLECTIVE FOCI AS A PREDICTOR OF VISUAL OUTCOME AND RECURRENCE FOR CENTRAL SEROUS CHORIORETINOPATHY.

PURPOSE: To investigate the association between baseline retinal microstructures including hyperreflective foci (HF), shown by spectral domain optical coherence tomography, and visual outcome and recurrence after laser photocoagulation for central serous chorioretinopathy. METHODS: We retrospectively reviewed 62 eyes from the medical records of 62 central serous chorioretinopathy patients. At the initial visit, baseline visual acuity, presence of photoreceptor granulation, subretinal fluid thickness, choroidal thickness at the macula, and retinal pigment epithelium status at the leakage site were examined. In addition, the numbers of HF at the macula and the leakage site were counted at the inner, outer, subretinal, and sub-retinal pigment epithelium segmented retinal layers. The statistical correlation was evaluated between the baseline characteristics and the duration of subretinal fluid resolution, duration of visual recovery, and recurrence. RESULTS: Sixty-one of the 62 eyes achieved Snellen best-corrected visual acuity ≥20/22 at the final visit. The duration of subretinal fluid resolution was positively associated with the number of total HF at the macula and the leakage site (P = 0.047 and P = 0.004, respectively). The duration for achieving best-corrected visual acuity ≥20/22 was positively associated with both the baseline logMAR best-corrected visual acuity and the total number of HF at the macula (P < 0.001 and P = 0.02, respectively). Recurrence was positively associated with the presence of irregular retinal pigment epithelium and the number of subretinal HF at the leakage site (P = 0.02 and P = 0.01, respectively). CONCLUSION: The baseline number of HF observed in spectral domain optical coherence tomography may be able to predict the course of anatomical and functional recovery, and the recurrence of central serous chorioretinopathy.

CORRELATION BETWEEN OPTICAL COHERENCE TOMOGRAPHIC HYPERREFLECTIVE FOCI AND VISUAL OUTCOMES AFTER ANTI-VEGF TREATMENT IN NEOVASCULAR AGE-RELATED MACULAR DEGENERATION AND POLYPOIDAL CHOROIDAL VASCULOPATHY.

PURPOSE: To investigate the correlation between hyperreflective foci (HF) on spectral domain optical coherence tomography at baseline and visual outcomes after intravitreal anti-vascular endothelial growth factor injection in neovascular age-related macular degeneration (nAMD) and polypoidal choroidal vasculopathy (PCV). METHODS: The authors retrospectively reviewed the medical records of 44 patients with nAMD and 44 patients with PCV. The number of HF was counted according to the location of HF on spectral domain optical coherence tomography: neurosensory retinal layer, outer retinal layer, and subretinal layer. Statistical correlation between final visual acuity and pretreatment and posttreatment optical coherence tomographic parameters including the number of HF, the status of external limiting membrane and inner segment ellipsoid zone was evaluated. RESULTS: The number of HF in all retinal layers was reduced in nAMD and PCV after treatment. In multivariate regression analysis, final visual acuity was associated with baseline visual acuity (P = 0.028), number of subretinal HF (P = 0.046), and ellipsoid zone disruption length (P = 0.009) in nAMD. In PCV, final visual acuity was associated with baseline visual acuity (P = 0.001), number of subretinal HF (P = 0.001), and pigment epithelial detachment thickness (P = 0.034). The baseline number of subretinal HF was correlated with final foveal thickness and thickness of subretinal fluid and choroidal neovascularization in nAMD (P = 0.002, P < 0.001, P = 0.009, respectively). In PCV, the baseline number of subretinal HF was correlated with final foveal thickness and ellipsoid zone and external limiting membrane disruption lengths (P = 0.027, P = 0.010, P = 0.020, respectively). CONCLUSION: The number of HF at subretinal layer on spectral domain optical coherence tomography at baseline might predict the final visual acuity after treatment in nAMD and PCV.

Gln-362 of angiopoietin-2 mediates migration of tumor and endothelial cells through association with α5ß1 integrin.

Angiopoietin-2 (Ang-2) not only regulates angiogenesis by binding to its well known receptor Tie2 on endothelial cells but also controls sprouting of Tie2-negative angiogenic endothelial cells and invasion of Tie2-negative non-endothelial cells by binding to integrins. However, the molecular mechanism of the Ang-2/integrin association has been unclear. In this study, we found that the Gln-362 residue of Ang-2 was essential for binding to α5ß1 integrin. A Q362E Ang-2 mutant, which still bound to Tie2, failed to associate with α5ß1 integrin and was unable to activate the integrin downstream signaling of focal adhesion kinase. In addition, unlike wild-type Ang-2, the Q362E Ang-2 mutant was defective in mediating invasion of Tie2-negative glioma or Tie2-positive endothelial cells. Furthermore, the tailpiece domain of the α5 subunit in α5ß1 integrin was critical for binding to Ang-2. Taken together, these results provide a novel insight into the mechanism of integrin regulation by Ang-2, which contributes to tumor invasion and endothelial cell migration in a Tie2-independent manner.

Clonidine Reduces Nociceptive Responses in Mouse Orofacial Formalin Model: Potentiation by Sigma-1 Receptor Antagonist BD1047 without Impaired Motor Coordination.

Although the administration of clonidine, an alpha-2 adrenoceptor agonist, significantly attenuates nociception and hyperalgesia in several pain models, clinical trials of clonidine are limited by its side effects such as drowsiness, hypotension and sedation. Recently, we determined that the sigma-1 receptor antagonist BD1047 dose-dependently reduced nociceptive responses in a mouse orofacial formalin model. Here we examined whether intraperitoneal injection of clonidine suppressed the nociceptive responses in the orofacial formalin test, and whether co-administration with BD1047 enhances lower-dose clonidine-induced anti-nociceptive effects without the disruption of motor coordination and blood pressure. Formalin (5%, 10 µL) was subcutaneously injected into the right upper lip, and the rubbing responses with the ipsilateral fore- or hind-paw were counted for 45 min. Clonidine (10, 30 or 100 µg/kg) was intraperitoneally administered 30 min before formalin injection. Clonidine alone dose-dependently reduced nociceptive responses in both the first and second phases. Co-localization for alpha-2A adrenoceptors and sigma-1 receptors was determined in trigeminal ganglion cells. Interestingly, the sub-effective dose of BD1047 (3 mg/kg) significantly potentiated the anti-nociceptive effect of lower-dose clonidine (10 or 30 µg/kg) in the second phase. In particular, the middle dose of clonidine (30 µg/kg) in combination with BD1047 produced an anti-nociceptive effect similar to that of the high-dose clonidine, but without a significant motor dysfunction or hypotension. In contrast, mice treated with the high dose of clonidine developed severe impairment in motor coordination and blood pressure. These data suggest that a combination of low-dose clonidine with BD1047 may be a novel and safe therapeutic strategy for orofacial pain management.

Exosomal proteins in the aqueous humor as novel biomarkers in patients with neovascular age-related macular degeneration.

Age-related macular degeneration (AMD) describes the progressive degeneration of the retinal pigment epithelium (RPE), retina, and choriocapillaris and is the leading cause of blindness in people over 50. The molecular mechanisms underlying this multifactorial disease remain largely unknown. To uncover novel secretory biomarkers related to the pathogenesis of AMD, we adopted an integrated approach to compare the proteins identified in the conditioned medium (CM) of cultured RPE cells and the exosomes derived from CM and from the aqueous humor (AH) of AMD patients by LC-ESI-MS/MS. Finally, LC-MRM was performed on the AH from patients and controls, which revealed that cathepsin D, cytokeratin 8, and four other proteins increased in the AH of AMD patients. The present study has identified potential biomarkers and therapeutic targets for AMD treatment, such as proteins related to the autophagy-lysosomal pathway and epithelial-mesenchymal transition, and demonstrated a novel and effective approach to identifying AMD-associated proteins that might be secreted by RPE in vivo in the form of exosomes. The proteomics-based characterization of this multifactorial disease could help to match a particular marker to particular target-based therapy in AMD patients with various phenotypes.