A novel approach for 25-gauge transconjunctival sutureless vitrectomy to evaluate vitreous substitutes in rabbits.

AIM: To improve the standard three-port vitrectomy for establishing and evaluating an endotamponade model in rabbits. METHODS: Three ports were prepared near the third eyelid of rabbits, and the infusion port was placed at the inferior nasal quadrant with the inserted cannula linking with a self-designed handheld rigid infusion catheter. All right eyes of rabbits underwent a modified 25-gauge vitrectomy and were subsequently filled with balanced salt solution, silicone oil, and eight-arm polyethylene glycols (8-arm PEGs) hydrogel separately for comparison. Ophthalmic examinations were performed regularly to record the changes after the surgery. RESULTS: Successful vitrectomy was achieved among 44 chinchilla rabbits. The mean operation time was 4.51±1.25min. Four eyes (9.1%) presented limited lens touch and two eyes (4.5%) showed retinal touch during surgery. Incision leakage was found in three eyes (6.8%) after surgery. There was no endophthalmitis, hemorrhage, or retinal detachment during the observation period and ophthalmic examinations after the implantation of vitreous substitutes. CONCLUSION: The modified technique of the standard vitrectomy applied in the endotamponade model in rabbits shows excellent safety and practicality.

Primary intracranial papillary meningioma: Analysis of factors of prognosis and systematic review.

OBJECTIVE: Papillary meningioma is rare and displays an aggressive clinical behavior with poor prognosis. Therefore, we performed an extensive literature review to evaluate the adverse factors and treatment strategy of survival. METHOD: We performed Ovid, Medline, Embase, Pubmed, Web of Science and Cochrane database queries for articles published between 1938 and 2019 with the search term "WHO grade III meningioma" or "papillary meningioma" and "central nervous system", "cerebral", or "intracranial". RESULTS: After a careful evaluation, a total of 19 studies were included. The entire cohort included the 67 patients, 34 (50.7%) were male and 33 (49.3%) were female with a mean age of 32.6 ± 2.1 years ranging from 4.5 months to 74 years. Gross total resection was achieved in 48 (71.6%) cases, and 29 (51.8%) patients received postoperative radiation. The mean follow-up period was 42.3 ± 4.4 months (range, 2-197 months). Thirty-six (53.7%) patients happened to recurrences, 11 (16.4%) patients happened to extracranial metastasis and 25 (37.3%) patients died. Univariate analysis revealed that the MIB > 5% trended toward a shorter time to recurrence (p = 0.084). Gross total resection was associated with favorable progression-free survival (p = 0.007) and overall survival (p = 0.001). Postoperative radiation was associated with favorable progression-free survival (p = 0.001). CONCLUSIONS: Gross total resection and adjuvant radiation were recommended as the initial treatment option for patients with papillary meningioma.

Upregulated inflammatory associated factors and blood-retinal barrier changes in the retina of type 2 diabetes mellitus model.

AIM: To examine the expression of high mobility group box-1 (HMGB-1) and intercellular adhesion molecule-1 (ICAM-1) in the retina and the hippocampal tissues; and further to evaluate the association of these two molecules with the alterations of blood-retinal barrier (BRB) and blood-brain barrier (BBB) in a rat model of type 2 diabetes. METHODS: The type-2 diabetes mellitus (DM) model was established with a high-fat and high-glucose diet combined with streptozotocin (STZ). Sixteen weeks after DM induction, morphological changes of retina and hippocampus were observed with hematoxylin-eosin staining, and alternations of BRB and BBB permeability were measured using Evans blue method. Levels of HMGB-1 and ICAM-1 in retina and hippocampus were detected by Western blot. Serum HMGB-1 levels were determined by enzyme-linked immunosorbent assay (ELISA). RESULTS: A significantly higher serum fasting blood glucose level in DM rats was observed 2wk after STZ injection (P<0.01). The serum levels of fasting insulin, Insulin resistance homeostatic model assessment (IRHOMA), total cholesterol (TC), total triglycerides (TG) and low density lipoprotein cholesterol (LDL-C) in the DM rats significantly higher than those in the controls (all P<0.01). HMGB-1 (0.96±0.03, P<0.01) and ICAM-1 (0.76±0.12, P<0.05) levels in the retina in the DM rats were significantly higher than those in the controls. HMGB-1 (0.83±0.13, P<0.01) and ICAM-1 (1.15±0.08, P<0.01) levels in the hippocampal tissues in the DM rats were also significantly higher than those in the controls. Sixteen weeks after induction of DM, the BRB permeability to albumin-bound Evans blue dye in the DM rats was significantly higher than that in the controls (P<0.01). However, there was no difference of BBB permeability between the DM rats and controls. When compared to the controls, hematoxylin and eosin staining showed obvious irregularities in the DM rats. CONCLUSION: BRB permeability increases significantly in rats with type-2 DM, which may be associated with the up-regulated retinal expression of HMGB-1 and ICAM-1.

Involvement of HMGB1 mediated signalling pathway in diabetic retinopathy: evidence from type 2 diabetic rats and ARPE-19 cells under diabetic condition.

AIMS: Inflammation is considered to play a critical role in the pathogenesis of diabetic retinopathy, and high mobility group box protein 1 (HMGB1) could promote inflammation as an alarmin. We investigated the expression of HMGB1 signalling pathway components in type 2 diabetic rat retinas and in high glucose cultured ARPE-19 cells. METHODS: Retinal expression of HMGB1 and its receptors in type 2 diabetic rats were detected by western blot and immunohistochemistry. ARPE-19 cells were cultured with low glucose, high glucose (with or without anti-HMGB1 antibody) or mannitol (control) for different lengths of time (12, 24, 48, 72 h). Then expression of HMGB1 and its receptors was measured by immunocytochemistry, ELISA or western blot. Nuclear factor κ-light-chain-enhancer of activated B cells (NF-κB) activity and tumour necrosis factor α (TNFα)/vascular endothelial growth factor (VEGF) production in retinas as well as in ARPE-19 cells were detected by ELISA. Furthermore, blood-retinal barrier permeability and ARPE-19 cell viability were measured by Evans-Blue and Cell Counting Kit-8 assay, respectively. RESULTS: HMGB1 signalling pathway components including receptors for HMGB1 as well as NF-κB and TNFα/VEGF were significantly upregulated in type 2 diabetic retinas and in high glucose treated ARPE-19 cells, compared to their respective counterparts. HMGB1 blockage significantly alleviated NF-κB activity and VEGF secretion in ARPE-19 cells cultured with high glucose. In addition, blood-retinal barrier permeability of the diabetic retinas increased, while cell viability of high glucose treated ARPE-19 cells decreased. CONCLUSIONS: Expression of HMGB1 signalling pathway components were increased in diabetic rat retinas and in ARPE-19 cells exposed to high glucose.