Objective To investigate the possible involvement of erythropoietin (EPO)/erythropoietin receptor (EPOR) system in neovascularization and vascular regeneration in diabetic retinopathy (DR). Methods EPOR positive...Objective To investigate the possible involvement of erythropoietin (EPO)/erythropoietin receptor (EPOR) system in neovascularization and vascular regeneration in diabetic retinopathy (DR). Methods EPOR positive circulating progenitor cells (CPCs: CD34^+) and endothelial progenitor cells (EPCs: CD34^+KDR^+) were assessed by flow cytometry in type 2 diabetic patients with different stages of DR. The cohort consisted of age- and sex-matched control patients without diabetes (n=7), non-prolif- erative DR (NPDR, n=7), proliferative DR (PDR, n=8), and PDR complicated with diabetic nephropathy (PDR-DN, n=7). Results The numbers of EPOR^+ CPCs and EPOR^+ EPCs were reduced remarkably in NPDR corn pared with the control group (both P(0.01), whereas rebounded in PDR and PDR-DN groups in varying degrees. Similar changes were observed in respect of the proportion of EPOR^+ CPCs in CPCs (NPDR vs. control, P(0.01) and that of EPOR^+ EPCs in EPCs (NPDR vs. control, P〈0.05). Conclusion Exogenous EPO, mediated via the EPO/EPOR system of EPCs, may alleviate the impaired vascular regeneration in NPDR, whereas it might aggravate retinal neovascularization in PDR due to a rebound of EPOR^+ EPCs associated with ischemia.展开更多
Objective To identify the possible association between C(-106)T polymorphism of the aldose reductase (ALR) gene and diabetic retinopathy (DR) in a cohort of Chinese patients with type 2 diabetes mellitus (T2DM...Objective To identify the possible association between C(-106)T polymorphism of the aldose reductase (ALR) gene and diabetic retinopathy (DR) in a cohort of Chinese patients with type 2 diabetes mellitus (T2DM). Methods From November 2009 to September 2010, patients with T2DM were recruited and assigned to DR group or diabetic without retinopathy (DWR) group according to the duration of diabetes and the grading of 7-field fundus color photographs of both eyes. Genotypes of the C(-106)T polymorphism (rs759853) in ALR gene were analyzed using the MassARRAY genotyping system and an association study was performed. Results A total of 268 T2DM patients (129 in the DR group and 139 in the DWR group) were included in this study. No statistically significant differences were observed between the 2 groups in the age of diabetes onset (P=0.10) and gender (P=0.78). The success rate of genotyping for the study subjects was 99.6% (267/268), with one case of failure in the DR group. The frequencies of the T allele in the C(-106)T polymorphism were 16.0% (41/256) in the DR group and 19.4% (54/278) in the DWR group (P=0.36). There was no signit^cant difference in the C(-106)T genotypes between the 2 groups (P=0.40). Compared with the wild-type genotype, odds ratio (OR) for the risk of DR was 0.7 (95% CI, 0.38-1.3) for the heterozygous CT genotype and 0.76 (95% CI, 0.18-3.25) for the homozygous TT genotype. The risk of DR was positively associated with microalbuminuria (OR=4.61; 95% CI, 2.34-9.05) and insulin therapy (OR=3.43; 95% CI, 1.94-6.09). Conclusions Microalbuminuria and insulin therapy are associated with the risk of DR in Chinese patients with T2DM. C(-106)T polymorphism of the ALR gene may not be significantly associated with DR in Chinese patients with T2DM.展开更多
Objective To analyze the effects of Dan Huang Ming Mu Recipe(DHMMR)(a pharmaceutical preparation from herbs and having the function of replenishing vital essence,removing heat,promoting blood circulation and excreting...Objective To analyze the effects of Dan Huang Ming Mu Recipe(DHMMR)(a pharmaceutical preparation from herbs and having the function of replenishing vital essence,removing heat,promoting blood circulation and excreting pathogenic water) on diabetic retinopathy(DR) after retinal laser photocoagulation through regulating the expression of vascular endothelial growth factor(VEGF) and pigment epithelium-derived factor(PEDF).Methods Forty male Brown Norway(BN) rats were randomly divided into blank group(group A,10 BN rats) and model group(30 BN rats).DR models were induced by 40 mg/kg streptozotocin(STZ) and the body weight and blood glucose of rats were monitored.After 12-week injection,fluorescein fundus angiography(FFA) and histopathological examination were detected to confirm the successful establishment of DR models.Subsequently,the right eyes of model group rats were conducted retinal laser photocoagulation with the left eyes having no retinal laser photocoagulation and rats of the model group were randomly divided into group B(the model control group),group C(the positive control group),and group D(the DHMMR group),with 10 rats in each group.Rats of the group A and the group B were given vehicle,and the group C were given calcium dobesilate suspension by gavage,and the group D were given DHMMR by gavage.After 4-week gavage,FFA was carried out to observe the fundus microvascular change.Then,the rats were sacrificed to do histopathological examinations and the serum levels of P-selectin,cAMP,cGMP,and the relative expression of the protein of VEGF and PEDF in retina were detected.Results After 12-week STZ injection,the blood glucose of the model group were pronouncedly higher than the blank group(P < 0.01).Fundus micro-hemangioma changes were observed in the rats of the model group through FFA,and the rats of the blank group did not see any changes.The pictures of HE staining showed that the retinal structure of the model group was more disordered than the blank group.After 4-week gavage,treatments with DHMMR showed dramatic reduction of serum levels of Pselectin,cAMP and cGMP compared with the group B(P < 0.01).FFA and histopathological examinations of DHMMR-treated rats revealed significantly suppression of retinal edema,fundus microvascular destruction and retinal destruction distinguishing from the group B.And the relative expression of VEGF protein of the group D and the group A was markedly lower than that of the group B(P < 0.01).The relative expression of PEDF protein of the group D and the group A was dramatically higher than that of the group B to the contrary(P < 0.01).Conclusions DHMMR demonstrates pronounced suppressive effects on the progression of DR after retinal laser photocoagulation,through down-regulating VEGF and upregulating PEDF.展开更多
Diabetic retinopathy is one of the main causes of visual impairment and blindness on a global scale. At present, thelimitations of anti-vascular endothelial growth factor agents, steroids, laser photocoagulation, and ...Diabetic retinopathy is one of the main causes of visual impairment and blindness on a global scale. At present, thelimitations of anti-vascular endothelial growth factor agents, steroids, laser photocoagulation, and vitreous surgery haveled to a growing awareness of the role of Chinese medicines in the treatment of diabetic retinopathy. This review firstdescribes the ingredients and characteristics of the formulae including Chinese herbal formulaes, Chinese patent drugsand ancient processed drugs and summarizes the application of Chinese medicines and their mechanisms of action in thetreatment of diabetic retinopathy. Due to the complexity of Chinese medicines, in-depth mechanisms, side effects of herb,and drug interactions need to be elaborated in future research. Chinese medicines have the potencial to protect theresidual eyesight and delay the progression of disease, thereby offering a beneficial, exploitable option in thetreatment/prevention of diabetic retinopathy.展开更多
Objective. To study the changes of microcirculation in patients with diabetic retinopathy(DR). Methods. Examination were performed in 153 cases of type Ⅱ diabetes mellitus, among them, 7...Objective. To study the changes of microcirculation in patients with diabetic retinopathy(DR). Methods. Examination were performed in 153 cases of type Ⅱ diabetes mellitus, among them, 72 cases were male, 81 cases were female, mean age 57.0±10.0 years, mean disease course 8.2±7.5 years. All cases were examined fundi by ophthalmologist, urinary albumin excretion rate (UAE) in 24 hours was measured by radioimmunoassay. Moreover, we examined the blood glucose, blood pressure, blood viscosity and observed the changes of naifold microcirculation. Results.It was found that there were more evident disturbance of microcirculation, markedly slowed velocity of blood flow(P<0.05), significantly increased aggregation of blood cells(P<0.05) and exudation around the loop(P<0.05) in the group with DR, compared with the group without DR. Conclusion. It was more evident disturbance of nailfold microcirculation in patients with diabetic retinopathy.展开更多
Cancer-associated retinopathy (CAR) typically has a sudden or progressive onset of severe visual loss and an ominous association with an occult malignancy which contains breast cancer. Pathologically, CAR is the degen...Cancer-associated retinopathy (CAR) typically has a sudden or progressive onset of severe visual loss and an ominous association with an occult malignancy which contains breast cancer. Pathologically, CAR is the degeneration of photoreceptors. But the precise mechanism has not been fully established, CAR may result from autoimmune mediated apoptosis. And in recent years, there also have been some results demonstrating that tumor derived angiogenic factors such as VEGF may also confer the development of CAR, which may offer novel avenues for the therapeutic intervention in CAR. Early initiation of immunosuppressive therapy is critical for vision preservation. Future developments in rapid identification and longitudinal quantification of antibody levels would enable individualized management in these patients. The goal of this review was to analyze the epidemiology, the clinical features, the diagnosis and management of retinopathy in the context of recent advances in the elucidation of breast cancer-associated retinopathy (BCAR) pathogenesis.展开更多
Diabetic retinopathy(DR) and age-related macular degeneration(AMD) are the leading causes of blindness in adults. The impact of these conditions on the quality of life is increasing in significance with a rise in life...Diabetic retinopathy(DR) and age-related macular degeneration(AMD) are the leading causes of blindness in adults. The impact of these conditions on the quality of life is increasing in significance with a rise in life expectancy. The role of hyperglycemia, oxidative stress and inflammatory responses in the development and/or progression of DR and AMD, and several other sight threatening ocular diseases, is well established. In proliferative retinopathy, signals sent by the retina for nourishment, triggers the growth of fragile and abnormal blood vessels. Changes in ocular pressure may lead to rupture of these blood vessels causing severe vision problems. Recent in vitro and preclinical studies demonstrate that certain phytochemicals possessing potent antioxidant and anti-inflammatory activity and ocular blood flow enhancing properties may be very useful in the treatment of, or as a prophylactic measure for, DR and AMD. Apart from these properties they have also been investigated for their anti-bacterial, hormonal, enzyme stimulation, and anti-angiogenic activities. The attractive aspect of these potential therapeutic candidates is that they can act on multiplepathways identified in the etiology of DR, AMD, cataract and other ocular diseases. However, results from clinical trials have been somewhat ambiguous, raising questions about the concentrations of these bioflavonoids achieved in the neural retina following oral administration. Unfortunately, as of date, an efficient noninvasive means to deliver therapeutic agents/candidates to the back-of-the eye is still not available. This review examines some of these promising natural agents and discusses the challenges encountered in delivering them to the posterior segment ocular tissues through the oral route.展开更多
Diabetic retinopathy (DR) is one of the microvascular complications of diabetes, which could be divided intonon-proliferative DR and proliferative DR according to the severity of retinopathy. Diabetic microangiopath...Diabetic retinopathy (DR) is one of the microvascular complications of diabetes, which could be divided intonon-proliferative DR and proliferative DR according to the severity of retinopathy. Diabetic microangiopathy notonly affects the eyesight of patients with diabetes, but also endangers the lives of patients. Therefore, DR has drawnmore and more attention from domestic and foreign scholars. The etiology and treatment of diabetes are reviewedto explore ways of treating diabetic retinopathy.展开更多
Objective To evaluate nitric oxide(NO)and vascular endothelial growth factor(VEGF)in vitreous humor and blood samples in patients with proliferative diabetic retinopathy(PDR)and in patients with branch retinal vein oc...Objective To evaluate nitric oxide(NO)and vascular endothelial growth factor(VEGF)in vitreous humor and blood samples in patients with proliferative diabetic retinopathy(PDR)and in patients with branch retinal vein occlusion(BRVO).Methods NO concentrations were determined by using the Greiss reaction in plasma and vitreous humor samples.VEGF levels were assayed by ELISA.The patients in the studies were divided into four groups:16 patients with PDR,5 patients with BRVO,11 patients with rhegmatogenous retinal detachment(RRD),and 10 patients with idiopathic macular hole(IMH).Results The vitreous fluid levels of NO were significantly higher in patients with PDR(15.2μmol/L,4.6-50.9μmol/L)than those in the other three groups(F=5.13,P=0.005).The concentrations of VEGF were significantly higher in patients with PDR and BRVO(1507.2 μg/mL,50.71-3722.0μg/ml;838.8μg/mL,159.6-3328.0μg/mL)than those in the other two groups(F=6.84,P=0.0008),but highest in PDR(T=3.92,P=0.001).There was no significant difference between NO and VEGF in serum in four groups.There was no correlation between concentrations of NO and VEGF in four groups whatever in vitreous or plasma(all P>0.05).Conclusion The results suggest that higher levels of NO and VEGF may be related to the angiogenesis in DR.展开更多
DR (diabetic retinopathy) is a most probable reason of blindness in adults, but the only remedy or escape from blindness is that we have to detect DR as early. Several automated screening techniques are used to dete...DR (diabetic retinopathy) is a most probable reason of blindness in adults, but the only remedy or escape from blindness is that we have to detect DR as early. Several automated screening techniques are used to detect individual lesions in the retina. Still it takes more dependency of time and experts. To overcome those problems and also automatically detect DR in easier and faster way, we took into soft computing approaches in our proposed work. Our proposed work will discuss several amounts of soft computing algorithms, it can detect DR features (landmark and retinal lesions) in an easy manner. Processes includes are: (1) Pre-processing; (2) Optic disc localization and segmentation; (3) Localization of fovea; (4) Blood vessel segmentation; (5) Feature extraction; (6) Feature selection; Finally (7) detection of diabetic retinopathy stages (mild, moderate, severe and PDR). Our experimental results based on Matlab simulation and it takes databases of STARE and DRIVE. Proposed effective soft computing approaches should improve the sensitivity, specificity and accuracy.展开更多
基金Supported by Sciences and Technology Commission of Shanghai Municipality (08ZR1422100 and 08410701200)
文摘Objective To investigate the possible involvement of erythropoietin (EPO)/erythropoietin receptor (EPOR) system in neovascularization and vascular regeneration in diabetic retinopathy (DR). Methods EPOR positive circulating progenitor cells (CPCs: CD34^+) and endothelial progenitor cells (EPCs: CD34^+KDR^+) were assessed by flow cytometry in type 2 diabetic patients with different stages of DR. The cohort consisted of age- and sex-matched control patients without diabetes (n=7), non-prolif- erative DR (NPDR, n=7), proliferative DR (PDR, n=8), and PDR complicated with diabetic nephropathy (PDR-DN, n=7). Results The numbers of EPOR^+ CPCs and EPOR^+ EPCs were reduced remarkably in NPDR corn pared with the control group (both P(0.01), whereas rebounded in PDR and PDR-DN groups in varying degrees. Similar changes were observed in respect of the proportion of EPOR^+ CPCs in CPCs (NPDR vs. control, P(0.01) and that of EPOR^+ EPCs in EPCs (NPDR vs. control, P〈0.05). Conclusion Exogenous EPO, mediated via the EPO/EPOR system of EPCs, may alleviate the impaired vascular regeneration in NPDR, whereas it might aggravate retinal neovascularization in PDR due to a rebound of EPOR^+ EPCs associated with ischemia.
基金Supported by the National Basic Research Program of China(973 Program,2007CB512201)the Beijing Municipal Health Bureau Grant(2009208)the Beijing Natural Science Foundation(7131007)
文摘Objective To identify the possible association between C(-106)T polymorphism of the aldose reductase (ALR) gene and diabetic retinopathy (DR) in a cohort of Chinese patients with type 2 diabetes mellitus (T2DM). Methods From November 2009 to September 2010, patients with T2DM were recruited and assigned to DR group or diabetic without retinopathy (DWR) group according to the duration of diabetes and the grading of 7-field fundus color photographs of both eyes. Genotypes of the C(-106)T polymorphism (rs759853) in ALR gene were analyzed using the MassARRAY genotyping system and an association study was performed. Results A total of 268 T2DM patients (129 in the DR group and 139 in the DWR group) were included in this study. No statistically significant differences were observed between the 2 groups in the age of diabetes onset (P=0.10) and gender (P=0.78). The success rate of genotyping for the study subjects was 99.6% (267/268), with one case of failure in the DR group. The frequencies of the T allele in the C(-106)T polymorphism were 16.0% (41/256) in the DR group and 19.4% (54/278) in the DWR group (P=0.36). There was no signit^cant difference in the C(-106)T genotypes between the 2 groups (P=0.40). Compared with the wild-type genotype, odds ratio (OR) for the risk of DR was 0.7 (95% CI, 0.38-1.3) for the heterozygous CT genotype and 0.76 (95% CI, 0.18-3.25) for the homozygous TT genotype. The risk of DR was positively associated with microalbuminuria (OR=4.61; 95% CI, 2.34-9.05) and insulin therapy (OR=3.43; 95% CI, 1.94-6.09). Conclusions Microalbuminuria and insulin therapy are associated with the risk of DR in Chinese patients with T2DM. C(-106)T polymorphism of the ALR gene may not be significantly associated with DR in Chinese patients with T2DM.
基金the funding support from the Provincial Natural Science Foundation General Program(No.2015JJ2109)Hunan Province Graduate Student Research Innovation Program(No.CX2018B473)+7 种基金Hunan Traditional Chinese Medicine Scientific Research Program(NO.201463 and NO.2017141)Key Scientific Research Project of Hunan Administration of Traditional Chinese Medicine(NO.201917)University-level Scientific Research Projects of Hunan University of Chinese Medicine(NO.2017029 and NO.2018XJJJ31)The Domestic Firstclass Discipline Construction Project of Chinese Medicine of Hunan University of Chinese MedicineCentral Finance Supported Local High School Construction ProjectState Administration of Traditional Chinese Medicine Ophthalmology Key Discipline Construction ProjectHunan Province Traditional Chinese Medicine Facial Feature Key Discipline Construction ProjectHunan Engineering Technology Research Center for the Prevention and Treatment of Otorhinolaryngologic Diseases and Protection of Visual Function with Chinese Medicine,Hunan Provincial Key Laboratory for the Prevention and Treatment of Ophthalmology and Otolaryngology Diseases with Traditional Chinese Medicine
文摘Objective To analyze the effects of Dan Huang Ming Mu Recipe(DHMMR)(a pharmaceutical preparation from herbs and having the function of replenishing vital essence,removing heat,promoting blood circulation and excreting pathogenic water) on diabetic retinopathy(DR) after retinal laser photocoagulation through regulating the expression of vascular endothelial growth factor(VEGF) and pigment epithelium-derived factor(PEDF).Methods Forty male Brown Norway(BN) rats were randomly divided into blank group(group A,10 BN rats) and model group(30 BN rats).DR models were induced by 40 mg/kg streptozotocin(STZ) and the body weight and blood glucose of rats were monitored.After 12-week injection,fluorescein fundus angiography(FFA) and histopathological examination were detected to confirm the successful establishment of DR models.Subsequently,the right eyes of model group rats were conducted retinal laser photocoagulation with the left eyes having no retinal laser photocoagulation and rats of the model group were randomly divided into group B(the model control group),group C(the positive control group),and group D(the DHMMR group),with 10 rats in each group.Rats of the group A and the group B were given vehicle,and the group C were given calcium dobesilate suspension by gavage,and the group D were given DHMMR by gavage.After 4-week gavage,FFA was carried out to observe the fundus microvascular change.Then,the rats were sacrificed to do histopathological examinations and the serum levels of P-selectin,cAMP,cGMP,and the relative expression of the protein of VEGF and PEDF in retina were detected.Results After 12-week STZ injection,the blood glucose of the model group were pronouncedly higher than the blank group(P < 0.01).Fundus micro-hemangioma changes were observed in the rats of the model group through FFA,and the rats of the blank group did not see any changes.The pictures of HE staining showed that the retinal structure of the model group was more disordered than the blank group.After 4-week gavage,treatments with DHMMR showed dramatic reduction of serum levels of Pselectin,cAMP and cGMP compared with the group B(P < 0.01).FFA and histopathological examinations of DHMMR-treated rats revealed significantly suppression of retinal edema,fundus microvascular destruction and retinal destruction distinguishing from the group B.And the relative expression of VEGF protein of the group D and the group A was markedly lower than that of the group B(P < 0.01).The relative expression of PEDF protein of the group D and the group A was dramatically higher than that of the group B to the contrary(P < 0.01).Conclusions DHMMR demonstrates pronounced suppressive effects on the progression of DR after retinal laser photocoagulation,through down-regulating VEGF and upregulating PEDF.
文摘Diabetic retinopathy is one of the main causes of visual impairment and blindness on a global scale. At present, thelimitations of anti-vascular endothelial growth factor agents, steroids, laser photocoagulation, and vitreous surgery haveled to a growing awareness of the role of Chinese medicines in the treatment of diabetic retinopathy. This review firstdescribes the ingredients and characteristics of the formulae including Chinese herbal formulaes, Chinese patent drugsand ancient processed drugs and summarizes the application of Chinese medicines and their mechanisms of action in thetreatment of diabetic retinopathy. Due to the complexity of Chinese medicines, in-depth mechanisms, side effects of herb,and drug interactions need to be elaborated in future research. Chinese medicines have the potencial to protect theresidual eyesight and delay the progression of disease, thereby offering a beneficial, exploitable option in thetreatment/prevention of diabetic retinopathy.
文摘Objective. To study the changes of microcirculation in patients with diabetic retinopathy(DR). Methods. Examination were performed in 153 cases of type Ⅱ diabetes mellitus, among them, 72 cases were male, 81 cases were female, mean age 57.0±10.0 years, mean disease course 8.2±7.5 years. All cases were examined fundi by ophthalmologist, urinary albumin excretion rate (UAE) in 24 hours was measured by radioimmunoassay. Moreover, we examined the blood glucose, blood pressure, blood viscosity and observed the changes of naifold microcirculation. Results.It was found that there were more evident disturbance of microcirculation, markedly slowed velocity of blood flow(P<0.05), significantly increased aggregation of blood cells(P<0.05) and exudation around the loop(P<0.05) in the group with DR, compared with the group without DR. Conclusion. It was more evident disturbance of nailfold microcirculation in patients with diabetic retinopathy.
文摘Cancer-associated retinopathy (CAR) typically has a sudden or progressive onset of severe visual loss and an ominous association with an occult malignancy which contains breast cancer. Pathologically, CAR is the degeneration of photoreceptors. But the precise mechanism has not been fully established, CAR may result from autoimmune mediated apoptosis. And in recent years, there also have been some results demonstrating that tumor derived angiogenic factors such as VEGF may also confer the development of CAR, which may offer novel avenues for the therapeutic intervention in CAR. Early initiation of immunosuppressive therapy is critical for vision preservation. Future developments in rapid identification and longitudinal quantification of antibody levels would enable individualized management in these patients. The goal of this review was to analyze the epidemiology, the clinical features, the diagnosis and management of retinopathy in the context of recent advances in the elucidation of breast cancer-associated retinopathy (BCAR) pathogenesis.
文摘Diabetic retinopathy(DR) and age-related macular degeneration(AMD) are the leading causes of blindness in adults. The impact of these conditions on the quality of life is increasing in significance with a rise in life expectancy. The role of hyperglycemia, oxidative stress and inflammatory responses in the development and/or progression of DR and AMD, and several other sight threatening ocular diseases, is well established. In proliferative retinopathy, signals sent by the retina for nourishment, triggers the growth of fragile and abnormal blood vessels. Changes in ocular pressure may lead to rupture of these blood vessels causing severe vision problems. Recent in vitro and preclinical studies demonstrate that certain phytochemicals possessing potent antioxidant and anti-inflammatory activity and ocular blood flow enhancing properties may be very useful in the treatment of, or as a prophylactic measure for, DR and AMD. Apart from these properties they have also been investigated for their anti-bacterial, hormonal, enzyme stimulation, and anti-angiogenic activities. The attractive aspect of these potential therapeutic candidates is that they can act on multiplepathways identified in the etiology of DR, AMD, cataract and other ocular diseases. However, results from clinical trials have been somewhat ambiguous, raising questions about the concentrations of these bioflavonoids achieved in the neural retina following oral administration. Unfortunately, as of date, an efficient noninvasive means to deliver therapeutic agents/candidates to the back-of-the eye is still not available. This review examines some of these promising natural agents and discusses the challenges encountered in delivering them to the posterior segment ocular tissues through the oral route.
文摘Diabetic retinopathy (DR) is one of the microvascular complications of diabetes, which could be divided intonon-proliferative DR and proliferative DR according to the severity of retinopathy. Diabetic microangiopathy notonly affects the eyesight of patients with diabetes, but also endangers the lives of patients. Therefore, DR has drawnmore and more attention from domestic and foreign scholars. The etiology and treatment of diabetes are reviewedto explore ways of treating diabetic retinopathy.
基金Supported by Shanghai Leading Academic Discipline Project(S30205)Shanghai Science and Technology Commission Foundation(08JC1415600)National Natural Science Foundation of China(60978030)
文摘Objective To evaluate nitric oxide(NO)and vascular endothelial growth factor(VEGF)in vitreous humor and blood samples in patients with proliferative diabetic retinopathy(PDR)and in patients with branch retinal vein occlusion(BRVO).Methods NO concentrations were determined by using the Greiss reaction in plasma and vitreous humor samples.VEGF levels were assayed by ELISA.The patients in the studies were divided into four groups:16 patients with PDR,5 patients with BRVO,11 patients with rhegmatogenous retinal detachment(RRD),and 10 patients with idiopathic macular hole(IMH).Results The vitreous fluid levels of NO were significantly higher in patients with PDR(15.2μmol/L,4.6-50.9μmol/L)than those in the other three groups(F=5.13,P=0.005).The concentrations of VEGF were significantly higher in patients with PDR and BRVO(1507.2 μg/mL,50.71-3722.0μg/ml;838.8μg/mL,159.6-3328.0μg/mL)than those in the other two groups(F=6.84,P=0.0008),but highest in PDR(T=3.92,P=0.001).There was no significant difference between NO and VEGF in serum in four groups.There was no correlation between concentrations of NO and VEGF in four groups whatever in vitreous or plasma(all P>0.05).Conclusion The results suggest that higher levels of NO and VEGF may be related to the angiogenesis in DR.
文摘DR (diabetic retinopathy) is a most probable reason of blindness in adults, but the only remedy or escape from blindness is that we have to detect DR as early. Several automated screening techniques are used to detect individual lesions in the retina. Still it takes more dependency of time and experts. To overcome those problems and also automatically detect DR in easier and faster way, we took into soft computing approaches in our proposed work. Our proposed work will discuss several amounts of soft computing algorithms, it can detect DR features (landmark and retinal lesions) in an easy manner. Processes includes are: (1) Pre-processing; (2) Optic disc localization and segmentation; (3) Localization of fovea; (4) Blood vessel segmentation; (5) Feature extraction; (6) Feature selection; Finally (7) detection of diabetic retinopathy stages (mild, moderate, severe and PDR). Our experimental results based on Matlab simulation and it takes databases of STARE and DRIVE. Proposed effective soft computing approaches should improve the sensitivity, specificity and accuracy.