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Microglial activation has been studied extensively in diabetic retinopathy. We have previously detected activation and migration of microglia in 8-week-old diabetic rat retinas. It is widely acknowledged that microglia-mediated inflammation contributes to the progression of diabetic retinopathy. However, existing cell models do not explore the role of activated microglia in vitro. In this study, microglia were subject to various conditions mimicking diabetic retinopathy, including high glucose, glyoxal, and hypoxia. Under high glucose or glyoxal treatment, microglia demonstrated only partially functional changes, while under hypoxia, microglia became fully activated showing enlarged cell bodies, enhanced migration and phagocytosis as well as increased production of pro-inflammatory factors such as cyclooxygenase-2 (COX-2), interleukin-1β (IL-1β), and inducible nitric oxide synthase (iNOS). The data indicate that hypoxia-treated microglia is an optimal in vitro model for exploration of microglia activation in diabetic retinopathy.

The pathophysiology of diabetic retinopathy (DR) was complex. Under hyperglycemic conditions, the release of proinflammatory cytokines and the adhesion of leukocytes to retinal capillaries contribute to endothelial damage and the subsequent increase in vascular permeability resulting in macular edema. Melatonin, produced in the retina to regulate redox reactions and dopamine metabolism, plays protective roles against inflammation and oxidative stress. Considering its anti-inflammatory and antioxidative properties, melatonin was speculated to exert beneficial effects in DR. In this study, we characterized the protective effects of melatonin on the inner blood-retinal barrier (iBRB), as well as the possible mechanisms in experimental DR. Results showed that in diabetic rat retinas, the leakage of iBRB and the expression of inflammatory factors (VEGF, TNF-α, IL-1β, ICAM-1, and MMP9) increased dramatically, while the expression of tight junction proteins (ZO-1, occludin, JAM-A, and claudin-5) decreased significantly. The above changes were largely ameliorated by melatonin. The in vivo data were confirmed in vitro. In addition, the protein expressions of p38 MAPK, NF-κB, and TXNIP were upregulated significantly in diabetes and were downregulated following melatonin treatment. Melatonin could maintain the iBRB integrity by upregulating the expression of tight junction proteins via inhibiting p38/TXNIP/NF-κB pathway, thus decreasing the production of inflammatory factors. This study may shed light on the development of melatonin-based DR therapy.

The objective of this study was to evaluate the effect of different dietary densities on growth performance, carcass characteristics, meat quality, serum metabolism, ruminal papillae morphology and liver injuries of steers. For this purpose, a total of eighteen Holstein steers were randomly fed one of the three diets: high energy and protein diet (H), standard energy and protein diet (C), and low energy and protein diet (L) for 11 months fattening with three-step finishing strategy. Steers fed with H diet had higher (p .05) average daily gain, feed efficiency, hot carcass weight, serum aspartate aminotransferase to alanine aminotransferase ratio, and monounsaturated fatty acids along with continuous low ruminal pH value, severer hepatic steatosis and ruminal papillae parakeratosis. Meanwhile, steers fed L diet increased the proportion of C20:0, C22:6n-3, saturated fatty acids and n-3 polyunsaturated fatty acids along with lower n-6 to n-3 ratio in longissimus dorsi muscle as compared to that of steers fed H diet. Dietary densities did not influence (p .10) proximate nutrients and sensory characteristics of beef. The present study indicates that Holstein steers could achieve better growth and carcass performance under high-density diet, whereas they are under threat of visceral injuries and metabolic disorders. This study gives comprehensive relationship between productivity and animal health and suggests that a proper diet should be adopted for fattening Holstein steers in consideration of both beef quality and quantity and animal health.

PURPOSE To compare structural and functional improvements in patients with vitreous haemorrhage (VH) with different IOPs re-established at the end of pars plana vitrectomy (PPV). METHODS It is a prospective, randomized, comparative, interventional study. Ninety-five patients with nonclearing VH were randomized to receive PPV with normalized IOPs of 15 mmHg (Group I: 32 eyes), 25 mmHg (Group II: 32 eyes) and 35 mmHg (Group III: 31 eyes) at the end of surgery. The grade of vitreous opacity and best-corrected visual acuity (BCVA) on postoperative day 1, week 1, month 1 and month 3 were compared with a mixed model for repeated measures analysis. RESULTS All 3 groups achieved significant improvement on postoperatively in BCVA (p

Background and Objective Recurrent retinal detachment (RD) in silicone oil-filled eyes is a serious condition. At the initial stage, it usually spares the macular and is localized in the inferior retina. The inability to locate the retinal breaks has been reported to be associated with a poor prognosis and has limited the use of conventional vitreoretinal surgeries. Demarcation laser photocoagulation (DLP) is widely accepted for treating macular-sparing RDs. For laser treatments to be effective, an adequate extent and the correct placement of the laser is of great importance. The purpose of this research was to compare the efficacy of 360° and localized DLP in the management of macular-sparing RD in silicone oil-filled eyes with no detected retinal breaks. Materials and Methods This is a retrospective, comparative, interventional study. The medical records of 48 consecutive eyes with macular-sparing RD in silicone oil-filled eyes with no detected retinal breaks were reviewed. Twenty-six patients (group I) received 360° DLP, and the remaining 22 patients (group II) underwent localized DLP. The anatomical and visual outcomes of the two groups were compared. Results The mean follow-up period was 12.54 ± 1.17 months. No significant difference was identified in the baseline characteristics. The single-operation success rate of 92.31% was achieved in group I, which was significantly higher than that of group II (59.09%, P = 0.01), and this trend was not weakened after adjusting for confounding factors (odds ratio: 0.002, P = 0.02). After salvage management of vitreoretinal surgeries, both groups had equivalent visual outcomes with silicone oil removal. Multivariate logistic regression also indicated that the radial extent of RD (odds ratio: 11.10, P = 0.04) was an independent predictor for laser treatment failure. Significant complications sufficient to require further operations included proliferative vitreoretinopathy in two (4.17%) eyes and epiretinal membrane in four (8.33%) eyes. Conclusions The 360° DLP achieved a better primary success rate and equivalent visual outcomes with localized DLP for macular-sparing RD in silicone oil-filled eyes with no detected retinal breaks. Lasers Surg. Med. © 2015 Wiley Periodicals, Inc.

Attempts were made to prepare thermoplastic elastomers (TPE) from scrap rubber power (SRP) and linear low-density polyethylene (LLDPE) as thermoplastic polymer matrix. The solid-phase grafted copolymer of LLDPE (LLDPE-g-VM) and epoxidized natural rubber (ENR) were used as dual compatibilizers to improve the interfacial adhesion between SRP and LLDPE. The compatibilized SRP/LLDPE blends had obviously improved the interfacial properties between SRP particles and LLDPE. Using this method, thermoplastic elastomer was prepared successfully. The mechanical properties especially elongation at break was improved significantly. SEM and TEM studies showed that the ENR/LLDPE-g-VM dual compatibilizer improved the distribution state of SRP particles in LLDPE and the adhesion between SRP and LLDPE. DSC results showed a distinct glass transition at 74°C of the interfacial region. The improvement in mechanical properties was attributed to the enhanced interfacial properties of the blend.