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Purpose: To analyze the distribution of fibrovascular proliferative membrane (FVPM) in proliferative diabetic retinopathy (PDR) patients that need treated with pars plana vitrectomy (PPV), and to evaluate the outcomes separately. Methods: Retrospective review of consecutive 25-G PPV cases operated for PDR between September 2018 and April 2020. All FVPMs were outlined and assigned to three groups: arcade type, juxtapapillary type and central type. General characteristics, operation-related variables, best-corrected visual acuity (BCVA) 12 month postoperative and complications were recorded. , All patients were followed up for over one year Results: In total, 93 eyes were recruited. Among them, the FVPMs distribution of nasotemporal and inferiosuperioral were significantly different (both p < 0.01), with 87 (93.55%) FVPMs located in the nasal hemispheres, and 67 (72.04%) in the inferior hemispheres. The eyes with a central FVPM required the longest operation time, with silicon oil used in most patients, generally combined with tractional retinal detachment (RD) and rhegmatogenous RD, as well as the worst postoperative best-corrected visual acuity and the highest rates of recurrent RD and iatrogenic retinal break formation (all p < 0.05). Conclusion: FVPMs were more commonly found in the nasal and inferior mid-peripheral retina in addition to the area of arcade vessels. Performing 25-G PPV for treating PDR eyes with a central FVPM had a relatively worse prognosis.

Retinal segmentation is a prerequisite for quantifying retinal structural features and diagnosing related ophthalmic diseases. Canny operator is recognized as the best boundary detection operator so far, and is often used to obtain the initial boundary of the retina in retinal segmentation. However, the traditional Canny operator is susceptible to vascular shadows, vitreous artifacts, or noise interference in retinal segmentation, causing serious misdetection or missed detection. This paper proposed an improved Canny operator for automatic segmentation of retinal boundaries. The improved algorithm solves the problems of the traditional Canny operator by adding a multi-point boundary search step on the basis of the original method, and adjusts the convolution kernel. The algorithm was used to segment the retinal images of healthy subjects and age-related macular degeneration (AMD) patients; eleven retinal boundaries were identified and compared with the results of manual segmentation by the ophthalmologists. The average difference between the automatic and manual methods is: 2-6 microns (1~2 pixels) for healthy subjects and 3-10 microns (1~3 pixels) for AMD patients. Qualitative method is also used to verify the accuracy and stability of the algorithm. The percentage of “perfect segmentation” and “good segmentation” is 98% in healthy subjects and 94% in AMD patients. This algorithm can be used alone or in combination with other methods as an initial boundary detection algorithm. It is easy to understand and improve, and may become a useful tool for analyzing and diagnosing eye diseases.

The size and shape of the foveal avascular zone (FAZ) have a strong positive correlation with several vision-threatening retinovascular diseases. The identification, segmentation and analysis of FAZ are of great significance to clinical diagnosis and treatment. We presented an adaptive watershed algorithm to automatically extract FAZ from retinal optical coherence tomography angiography (OCTA) images. For the traditional watershed algorithm, “over-segmentation” is the most common problem. FAZ is often incorrectly divided into multiple regions by redundant “dams”. This paper analyzed the relationship between the “dams” length and the maximum inscribed circle radius of FAZ, and proposed an adaptive watershed algorithm to solve the problem of “over-segmentation”. Here, 132 healthy retinal images and 50 diabetic retinopathy (DR) images were used to verify the accuracy and stability of the algorithm. Three ophthalmologists were invited to make quantitative and qualitative evaluations on the segmentation results of this algorithm. The quantitative evaluation results show that the correlation coefficients between the automatic and manual segmentation results are 0.945 (in healthy subjects) and 0.927 (in DR patients), respectively. For qualitative evaluation, the percentages of “perfect segmentation” (score of 3) and “good segmentation” (score of 2) are 99.4% (in healthy subjects) and 98.7% (in DR patients), respectively. This work promotes the application of watershed algorithm in FAZ segmentation, making it a useful tool for analyzing and diagnosing eye diseases.

INTRODUCTION The aim of the present study is to assess whether postoperative residual non-enhancing volume (PRNV) is correlated and predictive of overall survival (OS) in glioblastoma (GBM) patients. METHODS We retrospectively analyzed a total 134 GBM patients obtained from The University of Texas MD Anderson Cancer Center (training cohort, n = 97) and The Cancer Genome Atlas (validation cohort, n = 37). All patients had undergone postoperative magnetic resonance imaging immediately after surgery. We evaluated the survival outcomes with regard to PRNV. The role of possible prognostic factors that may affect survival after resection, including age, sex, preoperative Karnofsky performance status, postoperative nodular enhancement, surgically induced enhancement, and postoperative necrosis, was investigated using univariate and multivariate Cox proportional hazards regression analyses. Additionally, a recursive partitioning analysis (RPA) was used to identify prognostic groups. RESULTS Our analyses revealed that a high PRNV (HR 1.051; p-corrected = 0.046) and old age (HR 1.031; p-corrected = 0.006) were independent predictors of overall survival. This trend was also observed in the validation cohort (higher PRNV: HR 1.127, p-corrected = 0.002; older age: HR 1.034, p-corrected = 0.022). RPA analysis identified two prognostic risk groups: low-risk group (PRNV

Collecting geospatial data from location-based services can provide location evidence while analysing spatial information. However, releasing location data may result in the disclosure of sensitive personal information. The adaptive grid method (AG) uses differential privacy to protect information. In AG, the algorithm uses two levels of grids over data domain. However, it does not take into account the data distribution. Usually, the accuracy will be reduced in response to long-range counting queries. In this paper, the adjacent grid cells with similar data density are clustered together. Laplace noise is added to the clusters created by the clustering of the grid cells. The noisy count obtained from the grid cells that form each cluster is evenly redistributed to the grid cells in the cluster. Extensive experiments on real-world datasets showed that the query accuracy of the proposed method is higher than the existing methods.

Measures of intelligence, when broadcast, serve as salient signals of social status, which may be used to unjustly reinforce low-status stereotypes about out-groups' cultural norms. Herein, we investigate neurobehavioural signals manifest in small ( n = 5) groups using functional magnetic resonance imaging and a ‘ranked group IQ task’ where implicit signals of social status are broadcast and differentiate individuals based on their expression of cognitive capacity. We report an initial overall decrease in the expression of cognitive capacity in the small group setting. However, the environment of the ‘ranked group IQ task’ eventually stratifies the population into two groups (‘high performers’, HP and ‘low performers’, LP) identifiable based on changes in estimated intelligence quotient and brain responses in the amygdala and dorsolateral prefrontal cortex. In addition, we demonstrate signals in the nucleus accumbens consistent with prediction errors in expected changes in status regardless of group membership. Our results suggest that individuals express diminished cognitive capacity in small groups, an effect that is exacerbated by perceived lower status within the group and correlated with specific neurobehavioural responses. The impact these reactions have on intergroup divisions and conflict resolution requires further investigation, but suggests that low-status groups may develop diminished capacity to mitigate conflict using non-violent means.

We previously demonstrated that activation of peripheral group II mGluRs inhibits PGE2-induced thermal hyperalgesia. In the present study we examined the role of peripheral group II mGluRs in inflammation-induced mechanical allodynia in CD1 mice. Subcutaneous injection of group II mGluR agonists or antagonists into the plantar surface of the mouse hind paw did not alter mechanical thresholds, suggesting that peripheral group II mGluRs did not modulate basal mechanical sensation. We then used either PGE2 or carrageenan to induce mechanical allodynia and investigated the effects of activating or inhibiting peripheral group II mGluRs. PGE2-injected mice showed an 87±1% decrease of mechanical thresholds 75 min after the injection, whereas mice injected with group II mGluR agonists had no increase in sensitivity compared to vehicle-injected mice. In the carrageenan-induced inflammation model, 3 h after carrageenan injection the mechanical thresholds of mice injected with group II mGluR agonist APDC fully recovered to baseline levels while vehicle-injected mice showed only 43±8% recovery. The application of group II mGluR antagonist (LY341495) alone delayed the recovery of PGE2- and carrageenan-induced mechanical allodynia. Three hours after injection of carrageenan, LY341495-injected mice showed little or no recovery with mechanical thresholds 8±1% of pre-carrageenan baselines, compared to 57±8% of pre-carrageenan baselines in vehicle-injected mice at the same time point. Our results suggest that activation of peripheral group II mGluRs reduces inflammation-induced mechanical allodynia and that peripheral group II mGluRs may mediate endogenous anti-allodynia effects, which speed recovery from inflammation-induced hypersensitivity.

Tetrodotoxin (TTX)-resistant sodium currents are important in nociception and nociceptive sensitization, which is partially due to their cAMP/protein kinase A (PKA)-mediated enhancement. Here we studied the effects of group II mGluR activation on TTX-resistant sodium currents in cultured mouse dorsal root ganglion (DRG) neurons. Activation of adenylyl cyclase with forskolin caused an increase in the amplitude of TTX-R currents and a leftward shift of the activation curve. When neurons were treated with ammonium pyrrolidinedithiocarbamate (APDC), a selective group II mGluR agonist, both the forskolin-induced increase in current amplitude and the shift of activation curve were blocked. LY341495, a group II mGluR antagonist, prevented these inhibitory effects of APDC. Our results suggest that group II mGluRs can negatively regulate TTX-R sodium currents in mouse DRG neurons.

Previous studies have shown that group II metabotropic glutamate receptors (mGluRs) are present on the peripheral terminals of primary sensory neurons, suggesting that they might be involved in nociception. In this study, we investigated the modulation of nociception by peripheral group II mGluRs and the molecular basis of this modulation. Subcutaneous injection of a group II mGluR agonist, 2R,4R4-aminopyrrolidine-2,4-dicarboxylate (APDC), did not alter thermal sensitivity but blocked prostaglandin E(2)(PGE(2))-induced thermal hyperalgesia. This effect was blocked by (2s)-2-amino-2-[(1s,2s)-2-carboxycycloprop-1-yl]-3-(xanth-9-yl) propanoic acid, a selective group II mGluR antagonist. In cultured primary sensory neurons, APDC blocked PGE(2)-induced potentiation of capsaicin responses, which was abolished when neurons were pretreated with pertussis toxin. Similar potentiating effects induced by forskolin but not 8-bromo-cAMP were also blocked by the activation of group II mGluRs. These results indicate that peripheral group II mGluRs act via inhibition of adenylyl cyclase to reverse the sensitization of capsaicin receptors and the thermal hyperalgesia induced by PGE(2), and suggest that peripheral group II mGluRs might be targeted for therapeutic intervention in inflammatory pain states.