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AIM: To evaluate the potential efficacy and mechanisms of nintedanib in corneal neovascularization (NV) in rabbit models. METHODS: Corneal NV was induced using 1 mol/L NaOH. Rabbits (n=21) were randomized to 3 groups: Group 1 were treated with 0.9% NaCl, Group 2 with Avastin (5 mg/mL), and Group 3 with nintedanib (1 mg/mL). All treatments started 1d after alkaline burns and were topically performed 3 times a day for 2wk. Photographs were taken on a slit lamp microscope on day 7 and 14. The NV area, the length of the vascularization and angiogenesis index (AI) were used to evaluate the corneal NV. On day 14, the immunohistochemical (IHC) studies of the cornea were examined. Western blot was performed to test the expression levels of vascular endothelial growth factor (VEGF), Akt, p-Akt, P38, p-P38, MMP-2 and MMP-9. RESULTS: The corneal NV area, vessel length and AI in Group 3 were significantly lower than Group 2, with both being lower than Group 1. IHC staining showed that VEGF was significantly overexpressed in the epithelium and stroma of cornea following alkaline burns. In contrast, the level of VEGF was significantly suppressed in both Group 2 and Group 3. Western blot results further confirmed that, compared with Group 1, Group 3 had significantly reduced expressions of VEGF, Akt, p-Akt, p-P38, MMP-2, and MMP-9 in corneal tissues. Trends of lower levels of MMP-2, AKT, and p-AKT in Group 3 than Group 2 were identified. CONCLUSION: Nintedanib and Avastin can effectively inhibit corneal NV, with P38 MAPK and AKT signaling pathways being possibly involved. Nintedanib seems more effective than Avastin and has the potential to be a novel therapy for preventing corneal NV.

E-commerce agriculture has gradually become an important force in poverty alleviation. Some large e-commerce enterprises in China, such as Alibaba and JD, have carried out poverty alleviation activities with the support of the government. With the enthusiasm of consumers towards the goal of helping farmers, they can continue to develop e-commerce agriculture and efficiently achieve this goal. However, the unstable relationship among e-commerce enterprises, the government, and consumers with regard to poverty alleviation hinders the realization of poverty reduction goals. To promote the cooperation among the three parties under e-commerce poverty alleviation, this study uses the evolutionary game method. First, this study analyzes the collaborative mechanism of the government, e-commerce enterprises, and consumers participating in poverty alleviation. Second, based on the above analysis, a tripartite evolutionary game model is constructed. A payment matrix is established to analyze the factors that affect the strategic choices of participants, and the conditions for promoting the tripartite collaborative mechanism of poverty alleviation are discussed using numerical simulation. The results show the following: (1) The reduction in poverty alleviation costs and the increase in cooperation benefits are important factors in promoting the choice of poverty alleviation strategies. (2) E-commerce enterprises are more sensitive to consumer preferences for helping farmers. When consumer preferences for helping farmers are low, the government’s early efforts to participate in poverty alleviation can guide e-commerce enterprises and consumers to participate in cooperative poverty alleviation. (3) The government and e-commerce enterprises can reduce poverty alleviation incentives and agricultural product premiums by increasing the willingness of e-commerce enterprises and consumers to support farmers in the initial stage to promote the participation of all parties in poverty alleviation at a relatively low cost.

Blood vessel dysfunction causes several retinal diseases, including diabetic retinopathy, familial exudative vitreoretinopathy, macular degeneration and choroidal neovascularization in pathological myopia. Vascular endothelial growth factor (VEGF)-neutralizing proteins provide benefits in most of those diseases, yet unsolved haemorrhage and frequent intraocular injections still bothered patients. Here, we identified endothelial CD146 as a new target for retinal diseases. CD146 expression was activated in two ocular pathological angiogenesis models, a laser-induced choroid neovascularization model and an oxygen-induced retinopathy model. The absence of CD146 impaired hypoxia-induced cell migration and angiogenesis both in cell lines and animal model. Preventive or therapeutic treatment with anti-CD146 antibody AA98 significantly inhibited hypoxia-induced aberrant retinal angiogenesis in two retinal disease models. Mechanistically, under hypoxia condition, CD146 was involved in the activation of NFκB, Erk and Akt signalling pathways, which are partially independent of VEGF. Consistently, anti-CD146 therapy combined with anti-VEGF therapy showed enhanced impairment effect of hypoxia-induced angiogenesis in vitro and in vivo. Given the critical role of abnormal angiogenesis in retinal and choroidal diseases, our results provide novel insights into combinatorial therapy for neovascular fundus diseases.

BackgroundThe visual outcome of open globe injury (OGI)-no light perception (NLP) eyes is unpredictable traditionally. This study aimed to develop a model to predict the visual outcomes of vitrectomy surgery in OGI-NLP eyes using a machine learning algorithm and to provide an interpretable system for the prediction results.MethodsClinical data of 459 OGI-NLP eyes were retrospectively collected from 19 medical centres across China to establish a training data set for developing a model, called ‘VisionGo’, which can predict the visual outcome of the patients involved and compare with the Ocular Trauma Score (OTS). Another 72 cases were retrospectively collected and used for human–machine comparison, and an additional 27 cases were prospectively collected for real-world validation of the model. The SHapley Additive exPlanations method was applied to analyse feature contribution to the model. An online platform was built for real-world application.ResultsThe area under the receiver operating characteristic curve (AUC) of VisionGo was 0.75 and 0.90 in previtrectomy and intravitrectomy application scenarios, which was much higher than the OTS (AUC=0.49). VisionGo showed better performance than ophthalmologists in both previtrectomy and intravitrectomy application scenarios (AUC=0.73 vs 0.57 and 0.87 vs 0.64). In real-world validation, VisionGo achieved an AUC of 0.60 and 0.91 in previtrectomy and intravitrectomy application scenarios. Feature contribution analysis indicated that wound length-related indicators, vitreous status and retina-related indicators contributed highly to visual outcomes.ConclusionsVisionGo has achieved an accurate and reliable prediction in visual outcome after vitrectomy for OGI-NLP eyes.

AIM: To determine the effects of safranal on choroidal neovascularization (CNV) and oxidative stress damage of human choroidal microvascular endothelial cells (HCVECs) and its possible mechanisms. METHODS: Forty-five rats were used as a laser-induced CNV model for testing the efficacy and safety of safranal (0.5 mg/kg·d, intraperitoneally) on CNV. CNV leakage on fluorescein angiography (FA) and CNV thickness on histology was compared. HCVECs were used for a H2O2-induced oxidative stress model to test the effect of safranal in vitro. MTT essay was carried to test the inhibition rate of safranal on cell viability at different concentrations. Tube formation was used to test protective effect of safranal on angiogenesis at different concentrations. mRNA transcriptome sequencing was performed to find the possible signal pathway. The expressions of different molecules and their phosphorylation level were validated by Western blotting. RESULTS: On FA, the average CNV leakage area was 0.73±0.49 and 0.31±0.11 mm2 (P?=?0.012) in the control and safranal-treated group respectively. The average CNV thickness was 127.4±18.75 and 100.6±17.34 μm (P=0.001) in control and safranal-treated group. Under the condition of oxidative stress, cell proliferation was inhibited by safranal and inhibition rates were 7.4%-35.4% at the different concentrations. For tube formation study, the number of new branches was 364 in control group and 35, 42, and 17 in 20, 40, and 80 μg/mL safranal groups respectively (P

Severe mechanical ocular trauma with no light perception (NLP) predicts a poor prognosis of visual acuity and enucleation of the eyeball. Since the innovative treatment concept of exploratory vitreoretinal surgery has developed and treatment technology has advanced, the outcomes of severe ocular trauma treatment in NLP patients have greatly improved. However, there remains a lack of unified standards for the determination, surgical indication, and timing of vitrectomy in NLP eye treatment. To address these problems, we aimed to create evidence-based medical guidelines for the diagnosis, treatment, and prognosis of mechanical ocular trauma with NLP. Sixteen relevant recommendations for mechanical ocular trauma with NLP were obtained, and a consensus was reached. Each recommendation was explained in detail to guide the treatment of mechanical ocular trauma associated with NLP.

Neuroinflammation is believed to play a primary role in the pathogenesis of most neurodegenerative diseases including Alzheimer's disease, Parkinson's disease and schizophrenia. Currently, suitable in vitro neuroinflammation models for studying cellular interactions and inflammatory mechanisms at the neurovascular unit are still scarce. In this study, we established an experimentally flexible tri-culture neuroinflammation model combining murine microglial cells (N11), mouse neuroblastoma Nuro2A cell lines and brain microvascular endothelial MVEC(B3) cells in a transwell co-culture system stimulated with lipopolysaccharides. Neuroinflammation was induced in this tri-culture model as manifested by activated N11 cells via toll-like receptor 4, resulting in increased release of proinflammatory mediators (nitric oxide, interleukin-6 and tumour necrosis factor-α) through the activation of nuclear factor-κB signalling pathway. The released inflammatory cytokines from N11 in turn, damaged the tight junction in microvascular endothelial MVEC(B3) cells, increased permeability of endothelial barrier, and induced tau phosphorylation and up-regulated caspase-3 expression in mouse neuroblastoma Nuro2A cell lines, leading to neuroinflammation injury. In summary, this tri-culture inflammation model mimics the microenvironment, the cellular crosstalk and the molecular events that take place during neuroinflammation. It provides a robust in vitro model for studying neuroinflammation mechanisms and screening for potential therapeutics to treat various neurodegenerative diseases.

Power electronic devices such as Insulated Gate Bipolar Transistors (IGBT) are widely used in electronic systems. The failure of IGBT may bring fatal damage to the whole system. The ability to accurately predict the remaining useful life (RUL) of IGBT can provide a basis for intelligent equipment maintenance, thereby minimizing the risk of catastrophe failure at work. The research in this field aims to achieve accurate and timely RUL prediction of equipment. This paper exploited the IGBT accelerated aging data from NASA Ames Research Center, and the monitoring data of IGBT is collected under thermal overstress load condition with square signal bias at gate. This paper developed three machine learning models to predict the RUL of IGBT, including Back Propagation Neural Network(BPNN), Random Forest and Extreme Learning Machine. These models realize real-time prediction of RUL, and the performance of these models is observed and analyzed.

Blood vessel dysfunction causes several retinal diseases, including diabetic retinopathy, familial exudative vitreoretinopathy, macular degeneration and choroidal neovascularization in pathological myopia. Vascular endothelial growth factor (VEGF)-neutralizing proteins provide benefits in most of those diseases, yet unsolved haemorrhage and frequent intraocular injections still bothered patients. Here, we identified endothelial CD146 as a new target for retinal diseases. CD146 expression was activated in two ocular pathological angiogenesis models, a laser-induced choroid neovascularization model and an oxygen-induced retinopathy model. The absence of CD146 impaired hypoxia-induced cell migration and angiogenesis both in cell lines and animal model. Preventive or therapeutic treatment with anti-CD146 antibody AA98 significantly inhibited hypoxia-induced aberrant retinal angiogenesis in two retinal disease models. Mechanistically, under hypoxia condition, CD146 was involved in the activation of NFκB, Erk and Akt signalling pathways, which are partially independent of VEGF. Consistently, anti-CD146 therapy combined with anti-VEGF therapy showed enhanced impairment effect of hypoxia-induced angiogenesis in vitro and in vivo. Given the critical role of abnormal angiogenesis in retinal and choroidal diseases, our results provide novel insights into combinatorial therapy for neovascular fundus diseases.

BackgroundDendrobium mixture (DMix) is an effective treatment for diabetic nephropathy (DN), but the underlying molecular mechanism remains unclear. In this study, we investigated whether DMix regulates the transforming growth factor-β1 (TGF-β1)/Smads signal transduction pathway. MethodsTwenty-four db/db mice were randomly divided into three groups: the model, DMix, and gliquidone groups, while eight db/m mice were selected as the normal control group. The drug was administered by continuous gavage for 8 weeks. Body weight (BW), kidney weight (KW), kidney index, fasting blood glucose (FBG), blood lipid, 24-hour urinary albumin excretion rate, blood urea nitrogen, and serum creatinine levels were measured. Pathological changes in the renal tissue were observed using a light microscope. Real-time quantitative PCR and immunohistochemical staining were used to detect mRNA expression of TGF-β1 and alpha-smooth muscle actin (α-SMA) genes and proteins, respectively, in renal tissues. TGF-β1, Smad2, p-Smad2, Smad3, p-Smad3, and α-SMA expression levels were measured using western blotting. ResultsDMix significantly reduced FBG level, BW, KW, and blood lipid level, and improved renal function in db/db mice. Histopathology showed that DMix alleviated glomerular mesangial cell proliferation and renal interstitial fibrosis in db/db mice. Additionally, DMix reduced protein and mRNA expression of TGF-β1 and α-SMA, and inhibited Smad2 and Smad3 phosphorylation. ConclusionsThe findings suggest that DMix may inhibit renal fibrosis and delay the progression of DN by regulating the TGF-β1/Smads signaling pathway. Key words: Diabetic nephropathy, Dendrobium mixture, TGF-β1/Smads signaling pathway

Colon cancer is a highly metastatic gastrointestinal cancer. BMP activin membrane-bound inhibitor (BAMBI), as a pseudo-receptor of the tumor growth factor (TGF)-β signal transduction pathway, has previously been demonstrated to be involved in human cancers. The present study demonstrated that BAMBI-small interfering (si)RNA regulated the viability and motility of colon cancer by activating TGF-β signaling. The expression level of BAMBI was suppressed by transfecting BAMBI-siRNA into the SW480 and HT-29 colon cancer cell lines. Decreased cell proliferation and increased cell apoptosis were detected in SW480 and HT-29 cells transfected with BAMBI-siRNA. Decreased expression of proliferation marker proteins Ki67 and proliferating cell nuclear antigen and elevated expression of apoptosis marker proteins (caspases-3, −8 and −9) further verified the role of BAMBI-siRNA in inhibiting cell viability. Silencing of BAMBI strongly reduced the closing rate and the number of invasive cells compared with control group. BAMBI-siRNA additionally resulted in decreased expression of migration marker proteins matrix metalloproteinase-9 (MMP-9), MMP-14 and vascular endothelial cell growth factor. In addition, the expression of TGF-β and phosphorylated-mothers against decapentaplegic homolog (Smad) 2/3 was increased in W480 and HT-29 cells transfected with BAMBI-siRNA. Elevated expression of the downstream signaling molecule E2F transcription factor 4/5 and suppressed c-MYC were additionally detected in the BAMBI-siRNA group. Finally, the in vivo experiment in the CSC xenograft revealed that BAMBI-siRNA strongly reduced the tumor growth and tumor volume. BAMBI-siRNA inhibited hepatic metastases and the expression of metastasis-associated proteins. The upregulated expression of TGF-β signaling proteins were detected in the BAMBI-siRNA group compared with control group in vivo. Overall, the results of the present study indicated that the inhibition of BAMBI reduces the viability and motility of colon cancer and may involve activation of the TGF-β/Smad pathway in vitro and in vivo.

Background: The super-spreading events were associated with the outbreaks of SARS and MERS, but their association with the outbreak of COVID-19 was unknown before we first published a report in medRxiv preprint in March 2020. Here, we reported a super-spreading transmission chain of SARS-CoV-2 involving an index patient, seven cancer patients, 40 health care workers and four family members. Methods: We conducted a retrospective study to identify the index patient and the exposed individuals linked to a chain of transmission associated with COVID-19. We collected and analyzed the data on demographic features, exposure history, clinical presentation, laboratory investigation, radiological examination, and disease outcome of these patients. Results: We identified the index patient and another presumptive “super-spreader”, who initiated and amplified a super-spreading transmission chain associated with COVID-19, respectively. There were 31 female and 21 male patients in this cohort, and the median age was 37 years (range: 22-79 years). Each of them had an exposure history with the index patient or his close contacts. Approximately 87% (45/52) of the patients had fever or other symptoms, 96% (50/52) had abnormal chest CT-scan findings, 86% of the tested patients (39/45) were positive for SARS-CoV-2 in the nasopharyngeal or throat swab specimen, 85% of the tested patients (29/34) were positive for SARS-CoV-2-specific IgM and/or IgG, 15% of the RT-PCR positive patients were tested negative for the specific IgM and/or IgG at the convalescent phase, and 15% of the RT-PCR negative patients were tested positive for the specific IgM and/or IgG. The severe patients experienced a significant decrease in oximetry saturation, lymphocyte, and platelet counts, along with a significant increase in C-reactive protein, D-dimer, and lactate dehydrogenase. All six fatal cases had comorbidities and five of the seven cancer patients (71%) died within 2-20 days of the disease onset. Conclusions: Our findings suggested that the super-spreading events associated with COVID-19 took place at the early stage of the disease outbreak in Wuhan. The cancer patients appeared to be highly vulnerable to SASR-CoV-2 infection.

The demand for life-cycle management of weapons and equipment drives the research and development of radar fault prognostic and Health Management (PHM) technology. With the continuous development of information technology, digital circuits account for more and more of the radar due to their excellent reliability and stability. The digital circuit will be affected by the surrounding environmental stress (thermal stress and mechanical stress) in the process of use, which will cause deformation of printed circuit board and lead to the failure of the pin of the chip, and ultimately lead to the failure of the chip, which may lead to serious damage to the radar. The Field Programmable Gate Array (FPGA) chip, due to its Programmable characteristics and its important position in the digital circuit, we regard the monitoring of FPGA pin as the standard to judge whether the digital circuit communicates normally. In this paper, the damage of FPGA pin is monitored by means of solder joint-built in self test(sj-bist) and the monitoring circuit is designed by means of principle analysis and IP core design, and the monitoring results are analyzed quantitatively by circuit design. The simulation experiment is carried out by PSpice simulation software, and the feasibility of monitoring circuit design by sj-bist method is verified by circuit construction and simulation analysis. Finally, the influence of temperature and internal resistance on the monitoring accuracy is obtained through simulation experiment, and the monitoring results are modified through theoretical analysis to improve the monitoring accuracy of the sj-bist technology.

The demand for weapons and equipment life cycle management has promoted the research and development of radar fault prediction and health management (PHM) technology, and radar has also evolved from ex post maintenance to condition Based maintenance (CBM). With the continuous development of information technology, digital circuits, with their excellent reliability and stability, account for more and more in radar. The Ball Grid Array (BGA) encapsulated Field Programmable Gate Array (FPGA) chip's solder joint failure is difficult to detect directly, and the failure of the FPGA's solder joint can cause serious damage to the radar. In view of this situation, this paper introduces several methods and principles of solder joint fault detection, and expounds its advantages and disadvantages.

BackgroundSuper-spreading events were associated with the outbreaks of SARS and MERS, but their association with the outbreak of COVID-19 remains unknown. Here, we report a super-spreading transmission chain of SARS-CoV-2 involving an index patient, seven cancer patients, 40 health care workers and four family members.MethodsWe conducted a retrospective study to identify the index patient and the exposed individuals linked to a chain of transmission associated with COVID-19. We collected and analyzed the data on demographic features, exposure history, clinical presentation, laboratory investigation, radiological examination, and disease outcome of these patients.ResultsWe identified the index patient and another presumptive “super-spreader”, who initiated and amplified a super-spreading transmission chain associated with COVID-19, respectively. There were 31 female and 21 male patients in this cohort, and the median age was 37 years (range: 22-79 years). Each of them had an exposure history with the index patient or his close contacts. Approximately 87% (45/52) of the patients had fever or other symptoms, 96% (50/52) had abnormal chest CT-scan findings, 86% of the tested patients (39/45) were positive for SARS-CoV-2 in the nasopharyngeal or throat swab specimen, 85% of the tested patients (29/34) were positive for SARS-CoV-2-specific IgM and/or IgG, 15% of the RT-PCR positive patients were tested negative for the specific IgM and/or IgG at the convalescent phase, and 15% of the RT-PCR negative patients were tested positive for the specific IgM and/or IgG. The severe patients experienced a significant decrease in oximetry saturation, lymphocyte, and platelet counts, along with a significant increase in C-reactive protein, D-dimer, and lactate dehydrogenase. All six fatal cases had comorbidities and five of the seven cancer patients (71%) died within 2-20 days of the disease onset.ConclusionsThe super-spreading events were associated with the outbreak of COVID-19 in Wuhan and its impact on disease transmission warrants further investigation. Cancer patients appeared highly vulnerable to COVID-19. The finding that a significant portion of SARS-CoV-2 infected patients were tested negative for the serum specific IgM and IgG at the convalescent phase should be addressed by additional studies.

Highlights • A high rate of asymptomatic SARS-CoV-2 carriers was found in healthcare workers. • Asymptomatic individuals had lower antibody levels in the acute phase. • Asymptomatic IgG titration reduced during the early convalescent phase., Objectives To investigate the proportion and characteristics of asymptomatic infection among healthcare workers (HCWs). Methods This study retrospectively investigated 1407 HCWs who were screened for COVID-19 by chest computed tomography (CT) scans and nasopharyngeal swabs for SARS-CoV-2 nucleic acid. Demographics, CT features, nasopharyngeal swabs, baseline symptoms, and laboratory data were collected. Results Of 1407 HCWs, 235 had symptoms and 1172 were asymptomatic close contacts, of which, 107 were symptomatic cases and 84 were close contacts who had abnormal CT findings. Of 152 symptomatic individuals and 908 close contacts tested for SARS-CoV-2 nucleic acid, 122 symptomatic cases and 38 close contacts had positive reverse-transcriptase real-time polymerase chain (RT-PCR) test results. The rate of confirmed asymptomatic infections was 4.2% (38/908). Both symptomatic and asymptomatic infected cases had high titrations of specific IgG or had ≥four-fold increase in IgG during convalescence compared with the acute phase. Combining the RT-PCR tests and serological findings, the rate of asymptomatic infections was 9.7% (88/908). In terms of the duration of viral shedding, there was no significant difference between symptomatic mild/moderate participants and asymptomatic infections. Conclusions The findings demonstrated that a high rate of asymptomatic SARS-CoV-2 carriers existed among healthcare worker close contacts during the outbreak of COVID-19.

Purpose. Recent research has provided novel insight into the function of fibromodulin (FMOD) in wound healing and angiogenesis. The role of FMOD in initiation of proliferative vitreoretinopathy (PVR) has not been studied. This study investigated the effect of FMOD on human retinal pigment epithelial (RPE) cell, which plays an essential role in the progression of PVR, and the possible mechanisms. Methods. Small interfering (si) RNA-based gene transfer technology was used to decrease FMOD expression and to study its effects on RPEs in vitro. Cell Counting Kit-8 assays, transwells, and flow cytometry analysis were used to measure cell proliferation, migration, cell cycle, and apoptosis. Western blot was used to measure expression of vascular endothelial growth factor (VEGF), VEGF receptor 2 (VEGFR2), extracellular signal-related kinase 1/2 (ERK1/2), and phosphoinositide 3 kinase (PI3K/AKT). Results. After transfection of RPEs with a FMOD-specific siRNA, cell proliferation and migration were inhibited to the percentage of 65% ± 5% and 39% ± 10%, respectively, compared to the control group. Depletion of FMOD induced cell cycle arrest and apoptosis in RPE cells. Downregulation of VEGF, VEGFR2, and phosphorylated AKT (p-AKT) were detected in transfected RPEs. Conclusion. Depletion of FMOD selectively downregulated the expression of VEGF and VEGFR2 and inhibited the signaling pathway of AKT phosphorylation, which consequently inhibited the proliferation and migration of RPE Cell.

In order to improve detection and estimation performance of distributed Orthogonal-Frequency-Division Multiplexing (OFDM) Multiple-Input Multiple-Output (MIMO) radar system in multi-target scene, we propose a novel approach of Adaptive Waveform Design (AWD) based on a constrained Multi-Objective Optimization (MOO). The sparse measurement model of this radar system is derived, and the method based on decomposed Dantzig selectors is applied for the sparse recovery according to the block structures of the sparse vector and the system matrix. An AWD approach is proposed, which optimizes two objective functions, namely minimizing the upper bound of the recovery error and maximizing the weakest-target return, by adjusting the complex weights of the emitting waveform amplitudes. Several numerical simulations are provided and their results show that the detection and estimation performance of the radar system is improved significantly when this MOO-based AWD approach is applied to the distributed OFDM MIMO radar system. Especially, we verify the effectiveness of our AWD approach when the available samples are reduced severally and the technique of compressed sensing is introduced. Keywords: Adaptive waveform design, Compressed sensing, Distributed radar, Multi-objective optimization, Multiple-input multiple-output, Orthogonal-frequency-division multiplexing

The purpose of our study was to investigate the effects of pleiotrophin (PTN) in proliferative vitreoretinopathy (PVR) both in vitro and in vivo. Immunofluorescence was used to observe the PTN expression in periretinal membrane samples from patients with PVR and controls. ARPE-19 cells were exposed to TGF-β1. The epithelial-to-mesenchymal transition (EMT) of the ARPE-19 cells was confirmed by observed morphological changes and the increased expression of α-SMA and fibronectin at both the mRNA and protein levels. We used specific small interfering (si)RNA to knock down the expression of PTN. The subsequent effects of PTN inhibition were assessed with regard to the EMT, migration, proliferation, cytoskeletal arrangement, TGF-β signaling, PTN signaling, integral tight junction protein expression (e.g., claudin-1 and occludin), and p38 MAPK and p-p38 MAPK levels. Additionally, a PVR rat model was established by the intravitreal injection of ARPE-19 cells transfected with PTN-siRNA and was evaluated accordingly. PTN was highly expressed in PVR membranes compared to controls. PTN knockdown attenuated the TGF-β1-induced migration, proliferation, cytoskeletal rearrangement, and expression of EMT markers such as α-SMA and fibronectin in the ARPE-19 cells, and these effects may have been mediated through p38 MAPK signaling pathway activation. PTN silencing inhibited the up-regulation of claudin-1 and occludin stimulated by TGF-β1, and PTN knockdown inhibited the proliferative aspects of severe PVR in vivo. PTN is involved in the process of EMT induced by TGF-β1 in human ARPE-19 cells in vitro, and PTN knockdown attenuated the progression of experimental PVR in vivo. These findings provide new insights into the pathogenesis of PVR.

The present study aimed to evaluate the impact of dendrobium mixture (DMix) on the gene and protein expression of insulin signaling pathway-associated factors in the livers of diabetic rats. The molecular mechanisms by which DMix inhibits gluconeogenesis were also investigated. A total of 47 female Wistar rats were used in the present study. Of these, 11 rats were randomly selected as healthy controls and diabetes was induced in the remaining 36 rats by administering a high-fat and high-sugar diet for 6 weeks, followed by two intraperitoneal injections of streptozotocin. The 36 rats were screened for diabetes and then randomly divided into three groups: Model, metformin and DMix groups. Following 12 weeks of treatment, the fasting blood glucose (FBG), glycosylated serum protein (GSP), serum insulin, blood lipids [total cholesterol (Tch) and triglycerides (TG)], alanine transaminase (ALT) and aspartate transaminase (AST) were assessed. In addition, hematoxylin and eosin staining was used for histomorphological examination of the liver tissues. The mRNA expression of insulin receptor (InsR), forkhead box protein O1 (FoxO1), phosphoenolpyruvate carboxykinase (PEPCK) and glucose 6-phosphatase (G6Pase) in the liver was measured with reverse transcription-quantitative polymerase chain reaction and the protein expression of InsR, phosphoinositide-3-kinase (PI3K), phosphorylated (p)-PI3K, protein kinase B (Akt), p-Akt, FoxO1, PEPCK and G6Pase in the liver was measured by western blot analysis. The FBG, GSP, InsR, Tch, TG, ALT and AST levels were significantly lower in the DMix-treated group compared with the model group (P

Diabetic macular edema is major cause of vision loss associated with diabetic retinopathy. Breakdown of blood-retinal barrier, especially inner BRB, is an early event in pathogenesis of DR. Apelin, an endogenous ligand of APJ, mediates angiogenesis and is involved in the development of DR. The present study aimed to investigate effects and mechanism of apelin-13 in vascular permeability during DME. We verified apelin-13 was upregulated in DME patients’ vitreous. High glucose incubation led to a progressive increase of apelin-13, APJ, cytoskeleton, and tight junction proteins, including VE-Cadherin, FAK, Src, ZO-1, and occludin. Apelin-13 promoted HRMEC proliferation and migration and phosphorylation of both cytoskeleton and tight junction under both normal and high glucose conditions. Besides, apelin-13 activated PI-3K/Akt and MAPK/Erk signaling pathways, including PLCγ1, p38, Akt, and Erk both in HRMEC and in C57BL/6 mice. Meanwhile, F13A performed opposite effects compared with apelin-13. In in vivo study, apelin-13 was also upregulated in retina of db/db mice. Taken together, apelin-13 increased biologic activity of HRMEC, as well as expression of both cytoskeleton and tight junction in DME via PI-3K/Akt and MAPK/Erk signaling pathways. Apelin-13 as an early promoter of vascular permeability may offer a new perspective strategy in early treatment of DR.

Purpose The Slit-Robo signal has an important role in vasculogenesis and angiogenesis. Our study examined the expression of Slit2 and its receptor, Robo1, in a rat model of streptozotocin-induced diabetes and in patients with proliferative diabetic retinopathy. Methods Diabetes was induced in male Sprague-Dawley rats via a single, intraperitoneal injection of streptozotocin. The rats were sacrificed 1, 3 or 6 months after the injection. The expression of Slit2 and Robo1 in retinal tissue was measured by real-time reverse transcription polymerase chain reaction (RT-PCR), and protein levels were measured by western blotting and immunohistochemistry. Recombinant N-Slit2 protein was used to study the effects of Slit2 on the expression of VEGF in vivo. The concentration of Slit2 protein in human eyes was measured by enzyme-linked immunosorbent assay in 27 eyes with proliferative diabetic retinopathy and 28 eyes in control group. The expression of Slit2, Robo1 and VEGF in the excised human fibrovascular membranes was examined by fluorescence immunostaining and semi-quantitative RT-PCR. Results The expression of Slit2 and Robo1 in the retina was altered after STZ injection. Recombinant N-Slit2 protein did not increase the retinal VEGF expression. Vitreous concentrations of Slit2 were significantly higher in the study group than in the control group. In the human fibrovascular membranes of the study group, the co-localization of VEGF with the markers for Slit2 and Robo1was observed. The expression of Slit2 mRNA, Robo1 mRNA, and VEGF mRNA was significantly higher in human fibrovascular proliferative diabetic retinopathy membranes than in the control membranes. Conclusions The alteration of Slit2 and Robo1 expression in the retinas of diabetic rats and patients with proliferative diabetic retinopathy suggests a role for the Slit-Robo signal in the various stages diabetic retinopathy. Further studies should address the possible involvement of the Slit-Robo signal in the pathophysiological progress of diabetic retinopathy.

Clinical trials have revealed that the antivascular endothelial growth factor (VEGF) therapies are effective in retinopathy of prematurity (ROP). But the low level of VEGF was necessary as a survival signal in healthy conditions, and endogenous placental growth factor (PIGF) is redundant for development. The purpose of this study was to elucidate the PIGF expression under hypoxia as well as the influence of anti-VEGF therapy on PIGF.CoCl2-induced hypoxic human umbilical vein endothelial cells (HUVECs) were used for an in vitro study, and oxygen-induced retinopathy (OIR) mice models were used for an in vivo study. The expression patterns of PIGF under hypoxic conditions and the influence of anti-VEGF therapy on PIGF were evaluated by quantitative reverse transcription-polymerase chain reaction (RTPCR). The retinal avascular areas and neovascularization (NV) areas of anti-VEGF, anti-PIGF and combination treatments were calculated. Retina PIGF concentration was evaluated by ELISA after treatment. The vasoactive effects of exogenous PIGF on HUVECs were investigated by proliferation and migration studies.PIGF mRNA expression was reduced by hypoxia in OIR mice, in HUVECs under hypoxia and anti-VEGF treatment. However, PIGF expression was reversed by anti-VEGF therapy in the OIR model and in HUVECs under hypoxia. Exogenous PIGF significantly inhibited HUVECs proliferation and migration under normal conditions, but it stimulated cell proliferation and migration under hypoxia. Anti-PIGF treatment was effective for neovascular tufts in OIR mice (P0.05).The finding that PIGF expression is iatrogenically up-regulated by anti-VEGF therapy provides a consideration to combine it with anti-PIGF therapy.

Pathological retinal angiogenesis is a major cause of vision loss. Endostatin is a natural antiangiogenesis antitumor protein that is widely used in cancer studies. In this study, we investigated the efficacy and potential mechanisms of endostatin for the prevention of retinal neovascularization both in vitro and in vivo.Human umbilical vein endothelial cells (HUVECs) were used for the in vitro studies. HUVECs were incubated with endostatin or the vascular endothelial growth factor (VEGF) and endostatin for different time points. Cell proliferation, migration, cell cycling, and tube formation studies were carried out using a Cell Counting Kit-8 assay, a Transwell assay, flow cytometry, and a Matrigel assay, respectively. Enzyme-Linked Immunosorbent Assay (ELISA) was used to study VEGF and pigment epithelial-derived factor (PEDF) protein secretion from the HUVECs at different time points. A murine oxygen-induced retinopathy (OIR) model was used for the in vivo studies. Seven-day-old C57BL/6J pups (p7) were exposed to 75% oxygen for 5 days. On p12, the animals were returned to a normal atmosphere and were immediately injected intravitreously with 1.5 μL of a 5 mg/mL endostatin solution. At p18, the mice were perfused with fluorescein-dextran-FITC, and their retinas were flat mounted to measure the nonperfused area. Retinal VEGF and PEDF levels were also measured by ELISA Kits in the OIR mice at p18.In vitro, endostatin inhibited HUVEC proliferation in a dose-dependent manner and also inhibited HUVEC proliferation in a VEGF-containing medium. Additionally, endostatin can inhibit migration, tube formation, and VEGF secretion in HUVECs, while also inducing apoptosis in HUVECs at several time points. These effects were statistically significant when compared to the control group (P0.05). In vivo, a single intravitreous injection of endostatin reduced the retinal nonperfused area from 30% in the control group to 23% in the treatment group (P0.0001). Intravitrous injection of endostatin reduced VEGF levels in retinas, while it increased PEDF levels.Endostatin showed convincing inhibitory effects on angiogenesis both in vitro and in vivo. The inhibitory effects may be, at least partly, resulted from the restoration of the PEDF/VEGF ratio. These data suggest that endostatin could offer an innovative pharmaceutical strategy for the prevention of retinal neovascularization.

Adeno-associated virus type 2 (AAV2) mediated gene therapy providing a potential treatment in the eye. However, immune responses can limit virally mediated gene transfer and therapy. To assess preexisting AAV2 neutralizing factors (NF) titers in peripheral blood and the vitreous in patients with age-related macular degeneration (AMD) and polypoidal choroidal vasculopathy (PCV). 130 subjects were enrolled: 50 with neovascular AMD, 30 with PCV, and 50 controls. The serum and the vitreous were obtained for AAV2 NF assay. We found AAV2 NF are present in all of AMD, PCV patients and controls we tested. There were no significant differences in prevalence of NAb in serum between AMD, PCV and controls (P =0.999). There was no correlation between NF in serum and in vitreous (P>0.05), and NF in vitreous was significantly less than in serum. Our results for the first time showed in Chinese population, NF against AAV2 was present in serum of all the patients with AMD or PCV and controls, and there were no significant differences among these groups. Therefore, it demonstrated there were no correlations between AAV2 NF titer and these diseases. We found NF in vitreous was considerably less than in serum in all groups. We also found no direct correlation between NF in vitreous and in serum suggesting serum antibody levels may not be used to predict their counterparts in the vitreous. Our results will provide crucial information for future clinical studies in the development of new therapies based on AAV2 mediated gene delivery in the eye.

Purpose. To identify the predictors of visual response to the bevacizumab treatment of neovascular age-related macular degeneration (AMD).Design. A cohort study within the Neovascular AMD Treatment Trial Using Bevacizumab (NATTB).Methods. This was a multicenter trial including 144 participants from the NATTB study. Visual outcomes measured by change in visual acuity (VA) score, proportion gaining ≥15 letters, and change in central retinal thickness (CRT) were compared among groups according to the baseline, demographic, and ocular characteristics and genotypes. Results. Mean change in the VA score was 9.2 ± 2.3 SD letters with a total of 46 participants (31.9%) gaining ≥15 letters. Change in median CRT was −81.5 μm. Younger age, lower baseline VA score, shorter duration of neovascular AMD, and TT genotype inrs10490924were significantly associated with greater VA score improvement (P=0.028,P<0.001,P=0.02, andP=0.039, resp.). Lower baseline VA score and TT genotype inrs10490924were significantly associated with a higher likelihood of gaining ≥15 letters (P=0.028, andP=0.021, resp.).Conclusions. Baseline VA and genotype ofrs10490924were both important predictors for visual response to bevacizumab at 6 months. This trial is registered with the Registration no.NCT01306591.