Evaluation of a novel artificial intelligence-based screening system for diabetic retinopathy in community of China: a real-world study.

PURPOSE: To evaluate the performance of an AI-based diabetic retinopathy (DR) grading model in real-world community clinical setting. METHODS: Participants with diabetes on record in the chosen community were recruited by health care staffs in a primary clinic of Zhengzhou city, China. Retinal images were prospectively collected during December 2018 and April 2019 based on intent-to-screen principle. A pre-validated AI system based on deep learning algorithm was deployed to screen DR graded according to the International Clinical Diabetic Retinopathy scale. Kappa value of DR severity, the sensitivity, specificity of detecting referable DR (RDR) and any DR were generated based on the standard of the majority manual grading decision of a retina specialist panel. RESULTS: Of the 193 eligible participants, 173 (89.6%) were readable with at least one eye image. Mean [SD] age was 69.3 (9.0) years old. Total of 321 eyes (83.2%) were graded both by AI and the specialist panel. The κ value in eye image grading was 0.715. The sensitivity, specificity and area under curve for detection of RDR were 84.6% (95% CI: 54.6- 98.1%), 98.0% (95% CI: 94.3-99.6%) and 0.913 (95% CI: 0.797-1.000), respectively. For detection of any DR, the upper indicators were 90.0% (95% CI: 68.3-98.8), 96.6% (95% CI: 92.1-98.9) and 0.933 (95% CI: 0.933-1.000), respectively. CONCLUSION: The AI system showed relatively good consistency with ophthalmologist diagnosis in DR grading, high specificity and acceptable sensitivity for identifying RDR and any DR. TRANSLATIONAL RELEVANCE: It is feasible to apply AI-based DR screening in community. PRECIS: Deployed in community real-world clinic setting, AI-based DR screening system showed high specificity and acceptable sensitivity in identifying RDR and any DR. Good DR diagnostic consistency was found between AI and manual grading. These prospective evidences were essential for regulatory approval.

Effect of Endothelin-1 on proliferation, migration and fibrogenic gene expression in human RPE cells.

The pathology of the fibrotic proliferative vitreoretinopathy (PVR) membrane represents an excessive wound healing response characterised by cells' proliferation, migration and secretion of extracellular matrix molecules (ECMs). Retinal pigment epithelial (RPE) cells are a major cellular component of the fibrotic membrane. Endothelin-1 (ET-1) has been reported to be involved in the development of PVR in vivo research. However, little is known about the role of ET-1 in RPE cells in vitro. In the present study, we investigated the role of ET-1 in the proliferation, migration and secretion of ECMs (such as type I collagen and fibronectin) in RPE cells in vitro. Our results illustrated that ET-1 promoted the proliferation, migration and secretion of ECMs through the protein kinase B (Akt) and extracellular signal-regulated kinase (Erk) signaling pathways in RPE cells in vitro. These findings strongly suggested that ET-1 may play a vital role in the development of PVR.

The significance of the increased expression of phosphorylated MeCP2 in the membranes from patients with proliferative diabetic retinopathy.

The purpose of this study was to evaluate the correlation of expression of phosphorylated methyl-CpG binding protein 2-Ser421 (MeCP2-S421) and VEGF in the membranes of patients with PDR. We examined the expression of phospho-MeCP2-S80, S421, VEGF and PEDF in surgically excised PDR membranes from 33 patients with diabetes, and idiopathic epiretinal membranes from 11 patients without diabetes, using immunohistochemistry and western blot. The colocalization of MeCP2-S421 with VEGF, PEDF, CD31, GFAP and αSMA was revealed by fluorescent double labeling. The effect of CoCl2 and knock down MeCP2 using specific siRNA on the expression of MeCP2 and VEGF were analyzed in HUCAC cells by Western blot. We found that phospho-MeCP2-S421 was significantly increased in the membranes from the patients with PDR compared with the specimens from patients without diabetes (P < 0.01). The expression of phospho-MeCP2-S421 was much stronger than that of phospho-MeCP2-S80 in the PDR membranes. Double labeling showed that the high phospho-MeCP2-S421 expression was associated with strong expression of VEGF, but not PEDF. Further, phospho-MeCP2-S421 and VEGF were increased by the stimulation of CoCl2 and knock down MeCP2 inhibited the expression of VEGF. Our result suggests that phospho-MeCP2-S421 might involve in the pathogenesis of PDR.

Programmed Death 1 (PD-1) is involved in the development of proliferative diabetic retinopathy by mediating activation-induced apoptosis.

PURPOSE: Recent studies revealed that immunological mechanisms play a prominent role in the pathogenesis of proliferative diabetic retinopathy (PDR). Given the importance of the immune response in PDR and the significance of the programmed death 1 (PD-1) pathway as an immune regulatory pathway, the aim of this study is to determine the expression and functional characteristics of the PD-1 pathway in peripheral blood lymphocytes from patients with PDR. METHODS: Peripheral blood lymphocytes were obtained from patients with PDR, age-matched patients with diabetes mellitus and no diabetic retinopathy (DM-NDR), and controls. The mRNA expression of PD-1 and its ligands were determined using real-time PCR. The frequencies of PD-1 and its ligands, activation-induced apoptosis, IFN-γ, and IL-4 were determined by flow cytometry. RESULTS: The PD-1 mRNA expression markedly decreased, while the frequency of PD-1(+) cells increased in the PDR group compared with the DM-NDR and control groups. The expression of PD-ligand 1 (PD-L1) mRNA and PD-L1(+) cells in the PDR group was lower than that in the other two groups. In the PDR group, the frequency of Annexin V(+)PI(-) and Annexin V(+)PI(-)PD-1(+) cells increased, while the frequency of Annexin V(+)PI(-)PD-L1(+) cells decreased. Although their expression was upregulated, the ratio of PD-1(+) IFN-γ(+) to PD-1(+)IL-4(+) cells in the PDR group was not significantly different to that in the DM-NDR and control groups. CONCLUSIONS: These results suggest that PD-1 is involved in the development of PDR by mediating activation-induced apoptosis.

Differential expression of the inflammation-associated chemokines/cytokines in mouse lung after exposure to cigarette smoke and smoking cessation.

OBJECTIVE: To determine the changes in the airway inflammation-related cytokine/chemokine profiles after exposure to cigarette smoke (CS) and smoking cessation (SC). METHODS: A total of 18 male C57BL/6 mice were equally divided into three groups: CS group, SC group, and normal control group. The airway resistance, lung morphology, and collagen deposition around airways were determined. HE staining and Masson trichrome staining were used for histopathological analysis. The inflammatory cells in bronchoalveolar lavage fluid (BALF) were assessed. The inflammation-associated cytokines were determined using real-time PCR and immunohistochemistry. Expressions of CXCR3 ligands including the CXCL9, CXCL10, CXCL11 and other cytokines in lung tissue and BALF were also analyzed. RESULTS: The airway resistance significantly increased in both CS group and SC group when compared with the normal control group. Lung pathological scores in both CS group and SC group were also higher than that in the normal control group, while there was no significant difference between the CS group and SC group. Inflammatory cells including the neutrophils, macrophages, and lymphocytes also increased in both the CS group and SC group at both mRNA and protein levels. The mRNA levels of CXCL9, CXCL10, MMP9, and MMP12 were significantly higher in CS group and SC group than those in the normal control group (all P<0.05). The protein expression levels of CXCL9, CXCL10, CXCL11, MMP2, MMP9, MMP12, and TGF-Β1 were significantly higher in CS group and SC group than those in the normal control group (all P<0.05). Compared with the normal control group,the concentrations of CXCL9, CXCL10, CXCL11, IL-8, and TGF-Β1 in the BALF supernatants of the CS group and SC group significantly increased (P<0.05); in addition, the IL-6 and TNF-Α concentrations also increased in the CS group (both P<0.05). CONCLUSIONS: CS exposure triggers inflammatory cell flux and accumulation in the lung parenchyma and BALF. As a consequence, the inflammatory cytokines increase dramatically. After CS, the cytokines/chemokines can decrease, but is still higher than in non-smokers.

[Clinical significance of peripheral blood circular DNA level measurements in patients with acute myocardial infarction].

OBJECTIVE: To explore clinical value of circular DNA in acute myocardial infarction. METHODS: Venous blood (2 ml/head) of 40 healthy control and 40 patients with acute myocardial infarction within 48h of onset of illness and convalescent period was collected. The level of plasma circular DNA was detected by duplex real-time polymerase chain reaction assay. The levels of myocardial enzyme spectrum and cardiac troponin T (cTnT) were detected by biochemistry method. RESULTS: The level of circular DNA in control group and group of acute myocardial infarction before treatment was (21.5 +/- 10.7) ng/ml and (253.6 +/- 45.7) ng/ml, respectively (P = 0.000). The levels of serum myocardial enzyme spectrum and cTnT before treatment in patients with acute myocardial infarction were significantly higher than those of control group (P < 0.05). The level of circular DNA after treatment in patients with acute myocardial infarction was significantly decreased compared with that before treatment (P = 0.000), the levels of myocardial enzyme spectrum and cTnT were also significantly reduced (P < 0.05). There was significant correlation between the level of circular DNA and those of CK-MB and cTnT, r = 0.613, 0.654, P = 0.032, 0.021. CONCLUSION: Circular DNA can be used as a marker of sensitively reflecting myocardial cell injury.

[The level of peripheral circular DNA in patients with hand foot and mouth disease].

OBJECTIVE: To determine the circular DNA level of patients with hand foot and mouth disease (HFMD) and evaluate its potential clinical value. METHODS: Venous blood in 30 healthy children and 78 patients with HFMD within 3 days of onset of illness and convalescent period was collected. The level of plasma circular DNA was detected by duplex real-time polymerase chain reaction assay. Blood sugar, high-sensitive CRP(hs-CRP) and leucocyte were also detected. RESULTS: The level of circular DNA in control group was (6.57 +/- 4.67) ng/ml. The level of circular DNA in ordinary and severe HFMD patients was (11.51 +/- 7.75) ng/ml and (20.59 +/- 10.67) ng/ml before treatment, respectively. The levels of circular DNA in ordinary and severe HFMD patients were significantly higher than that in control group (P = 0.021; 0.000); the level of circular DNA in severe HFMD patients was significantly higher than that in ordinary HFMD patients (P = 0.011). The level of circular DNA in severe HFMD patients after treatment were significantly lower than that before treatment (P = 0.033). The level of circular DNA before treatment and after treatment in ordinary HFMD patients had no significant difference. The levels of blood sugar and hs-CRP in severe HFMD patients were higher than those in ordinary before treatment (P = 0.045; 0.011). The levels of blood sugar and hs-CRP before treatment and after treatment in ordinary HFMD patients had no significant change. There was significantly positive correlation between the level of circular DNA and that of hs-CRP in HFMD patient (P = 0.021), but there was no correlation between the level of circular DNA and that of blood sugar and leucocyte. CONCLUSIONS: The level of circular DNA not only become an early identification marker of severe HFMD patients, but also become monitoring marker of effect of treatment.

[The surgical timing and effects for vitreous hemorrhage caused by ocular blunt trauma].

OBJECTIVE: To investigate the surgical timing and effects for vitreous hemorrhage caused by blunt ocular trauma. METHOD: 116 eyes of vitreous hemorrhage caused by ocular blunt trauma were divided into two groups, non-vitrectomy group (46 eyes) and vitrectomy group (70 eyes). The treating results and follow-up results were compared. RESULTS: 50 of 70 eyes (71.4%) in vitrectomy group and 10 of 46 eyes (21.7%) in non-vitrectomy group achieved a visual acuity of 0.1 or better over a follow-up period of 1 month, which indicated a significant difference between two groups. In the non-vitrectomy group, visual acuity of 10 eyes were better than 0.1, 7 eyes (70.0%) of them improved within 2 weeks of injury. In surgery group, 27.1% underwent only vitrectomy and 70.9% needed combining with other manipulations. In vitrectomy group the retina detachment was found in 3 eyes (4.3%) post-operatively and were cured by second operation. In non-vitrectomy group, the retinal detachment was found in 14 eyes (30.4%) during the follow-up period, and 8 eyes (72.7%) of 11 eyes received operation were cured. CONCLUSION: Early vitreous surgery can improve curative effect for vitreous hemorrhage caused by blunt ocular trauma when no improvement was observed after applied drugs 2 - 3 weeks.