Epigenetic modifications such as DNA methylation, histone post-translational modifications, non-coding RNA are reversible, heritable alterations which are induced by environmental stimuli. Major risk factors of diabetes and diabetic complications including hyperglycemia, oxidative stress and advanced glycation end products, can lead to abnormal epigenetic modifications in retinal vascular endothelial cells and retinal pigment epithelium cells. Epigenetic mechanisms are involved in the pathogenesis of macular edema and neovascularization of diabetic retinopathy (DR), as well as diabetic metabolic memory. The heritable nature of epigenetic marks also playsakey role in familial diabetes mellitus. Further elucidation of epigenetic mechanisms in DR can open the way for the discovery of novel therapeutic targets to prevent DR progression.
Objective lt;brgt;To evaluated the effect of transpupillary thermotherapy (TTT) on age-related macular degeneration (AMD). lt;brgt; lt;brgt;Methods lt;brgt;Sixty-two cases (62 eyes) of exudative AMD were managed with TTT. Before treatment, 58 cases underwent fundus fluorescein angiography(FFA),42 cases underwent simultaneous indocyanine green angiography (ICGA), and 56 cases underwent optic coherence tomography (OCT).TTT was delivered using a 810 nm diode laser with variable spot sizes 0.5-3.0 mm and power range 60-40 mW,60 seconds duration. Sixty-two cases were followed up for 1-10 months with 4.8 months average. lt;brgt; lt;brgt;Results lt;brgt;The visual acuities of last visit were compared with those before the treatment. The visual acuity was unchanged in 43 cases (69.3%), improved in 15 cases (24.2%), and declined in 4 cases (6.5%). OCT was re-done in 51 cases and compared with OCT images before TTT treatment. The height of macular edema was unchanged in 29 cases (56.9%), decreased in 18 cases (35.3%), and increased in 4 cases (7.8%). The amelioration of visual acuity was compatible with that of macular configuration in the majority of cases (74.5%). Only in 13 cases (25.5%) the amelioration of visual acuity lagged behind that of macular configuration. The re-treatment was performed in 18 cases (29.1%), probably due to insufficiency of laser power. No side-effect was found. lt;brgt; lt;brgt;Conclusion lt;brgt;TTT makes most of the cases of exudative AMD retaining or improving their visual acuity. The employment is secured. Further exploration is needed in order to obtain the parameters of the laser treatment. (Chin J Ocul Fundus Dis, 2002, 18: 180-183)
Objective To explore the effects of Neurogenesin 1 (Ng1) gene on functional recovery after spinal cord injury (SCI) and its mechanism. Methods Thirty-six rats (aging 4 months, weighing 230 g and being male or female), were randomly divided into two groups: experimental group (n=18) and control group (n=18). After spinal cord contusive injury at T10 level was made in all these rats using modified Allen’s method, Ng1 recombinant plasmid and blank plasmid were transfectedinto the damaged areas of exprimental group and control group respectively by Alzet pumps. At 1 day, 1 week, 2 weeks, 3 weeks, and 4 weeks after SCI, Basso-Beattle-Bresnahan (BBB) Rating Scale was used to observe the recovery of motor function. At 1 week after injury, the expressions of Ng1 mRNA and protein in injured spinal cord were detected by RT-PCR and Western blot techniques. And at 2 and 4 weeks, double immunofluorescence and histopathologic examinations were performed to study the prol iferation of the adult endogenous neural stem cells and pathological change after SCI. Results At 1-4 weeks after SCI, the BBB scores in the exprimental group was significantly higher than that in control group (P lt; 0.05), and at 4 weeks the BBB score of the experimental group (16.80 ± 1.79) was significantly higher than that of the control group (9.60 ± 1.67), (P lt; 0.01). RTPCR and Western blot showed that the mRNA and protein expressions of Ng1 were observed in the exprimental group and no expression was seen in the control group. Histologic observation showed that the morphology of spinal cord and neurons in the exprimental group was better than that in the control group and was close to the normal tissue. The mean number of Nestin+/ BrdU+ newborn endogenous neural stem cells in the exprimental group was significantly more than that in control group (P lt; 0.05). Conclusion Ng1 gene could promote the prol iferation of endogenous neural stem cells and protect the injured neurons, which enhances the repair of the motor function after SCI.
ObjectiveTo identify and observe disease-causing gene variants and clinical phenotypes in a Han Chinese family with Leber congenital amaurosis (LCA). MethodsA retrospective study. A patient with LCA10 and his parents who had presented at Department of Ophthalmology of Henan Provincial People's Hospital on May 2022 were selected as the study subject. Detailed medical and family histories were recorded, fundus photography and flash electroretinogram (F-ERG) were performed. Peripheral venous blood samples (3 ml) of the proband and his parents were collected to extract whole genomic DNA, then whole exome sequencing (WES) and mitochondrial DNA (mtDNA) sequencing were carried out for the proband to determine the disease-causing gene and variants. All variants were annotated by bioinformatics analysis. According to the American College of Medical Genetics and Genomics (ACMG) guidelines, the pathogenicity of all detected variants were evaluated. Candidate variants were verified by Sanger sequencing, and in vitro minigene assay were performed to evaluate the impact of the missense variant with insufficient evidence on mRNA splicing. ResultsThe proband, male, 7-month-old, presented with an inability to follow light or objects, eye poking, photophobia, nystagmus, partial loss of retinal pigment epithelium around the fovea of the macula. At the age of 2 years old, F-ERG revealed severe reduction, elongation, or even no waveform of a-wave and b-wave in both eyes. No obvious abnormality was found in the clinical phenotype of his parents. The result of WES revealed that the proband carried two variants in exon 40 and exon 2 of CEP290, a frameshift variant c.5515_5518del (p.Glu1839Lysfs*11) (V1) and a novel missense variant c.74C>T (p.Ala25Val) (V2), respectively. The result of mitochondrial DNA sequencing was negative. Sanger sequencing confirmed that the heterozygous frameshift variant was inherited from his father and the heterozygous novel missense variant was inherited from his mother, which constituted compound heterozygous variants. In vitro minigene splicing assay confirmed that V2 created a new splicing donor at exon 2, leading to the in-frame deletion of 30bp fragment during transcription and loss of 10 amino acid residues in the protein. The two variants were pathogenic (V1) and likely pathogenic (V2) based on ACMG guidelines, respectively. ConclusionsThe c.5515_5518del and novel c.74C>T compound heterozygous variants of the CEP290 gene probably are the cause of LCA10 in this family, which lead to the production of a truncated protein and aberrant splicing of pre-mRNA, respectively. LCA is characterized by early onset, severe impairment of visual function, and a wide range of disease-causing variations.
PURPOSE:To investigate the spatial and temporal relation of fibronectin(Fn),basic fibroblast growth factor(b-FGF)and astrocytes with the retinal vascular developmemt of human fatuses. METHODS:The retinas of 86 human fetuses from 13th week to 40th week were studied by immunohistochemical methods and light microscopy. RESULTS:Fn immunoreativity was localized in spindle cells ,vascular endothelial cells and extracellular matrix ahead of the spindle cells,vascular endothelial cells,ganglion cells and cone cells were b-FGF immunopositive. The b-FGF immunoreactivity in ganglion cells and cone cells appeared earlier than the vascularization nearby.Astrocytes migrated to ora serrata in close association with the spindle cells.and sent numerous processes to ensheath the blood vessels formed in two processes of retinal vascuiarlzation. CONCLUSION:These results suggest that Fn ,b-FGF and astrocytes were involved in modulating both of two processes of retinal vascularizalion. （Chin J Ocul Fundus Dis,1996,12:180-182）
Objective To clarify the role of gastrokine 1 in the process of formation and development of gastric cancer. Methods The expressions of gastrokine 1 in gastric cancer and paracancerous tissues of 52 patients with gastriccancer were detected by real-time fluorescence quantitative polymerase chain reaction （RT-PCR） and immunohistochemistry. Meanwhile the relationship of the expression level of gastrokine 1 with clinicopathologic characteristics were analyzed. Results The expression levels of gastrokine 1 gene and protein in the gastric cancer tissues were significantly lower than those in the paracancerous tissues （P＜0.01）. No significant relationship was found between expression of gastrokine 1 gene and clinicopathologic features including tumor location， depth of invasion， differentiation， lymph node metastasis， tumor stage， gender， age， and preoperative peripheral blood CEA and CA19-9 levels （P＞0.05，respectively）. What’s more， the expression level of gastrokine 1 gene in gastric cancer tissues of Helicobacter pylori （HP）-positive patients was lower than that in the negative ones （P＜0.05）. Conclusions Gastrokine 1 may play a significant role as an anti-oncogene in the process of the formation and development of gastric cancer. Its effect may become weak due to HP infection in gastric cancer patients.
Objective To investigate the tumor suppressor genes of phlegm DNA in smokers, and analyze the correlation between methylation level of tumor suppressor gene promoter and chronic mucus hypersecretion (CMH). Methods The study recruited the patients who were admitted in the respiratory department during 2013-2016 in this hospital, including 700 cases of urban smokers and 380 cases of rural smokers. Eleven genes commonly silenced by promoter methylation in lung cancer and associated with cancer risk were selected. Methylation specific PCR (MSP) was used in the sputum sample of 700 individuals in the urban smokers cohort. Replication was performed in 380 individuals from the rural smokers cohort. Results CMH was significantly associated with an overall increased number of methylated genes, with SULF2 methylation demonstrating the most consistent association. The association between SULF2 methylation and CMH was significantly increased in males but not in females both in the urban and rural groups (OR=2.73, 95%CI 1.53-4.93, P=0.001; OR=2.96, 95%CI 1.47-5.94, P=0.002, respectively). Furthermore, the association between methylation and CMH was more obvious among 139 male former smokers with persistent CMH compared with current smokers (SULF2, OR=3.64, 95%CI 1.57-8.35, P=0.002). Conclusion These findings demonstrate that especially male former smokers with persistent CMH have markedly increased promoter methylation of lung cancer risk genes and potentially could be at increased risk for lung cancer.
OBJECTIVE To review the fundamental research and the experimental study of vascular endothelial growth factor (VEGF). METHODS The laboratory information and experimental study of VEGF were extensively reviewed. RESULTS VEGF, as a mitogen specifically for endothelial cells, could bly stimulate angiogenesis as well as vascular permeability, especially in hypoxia state. Experimentally, survival area and viability of flaps could be increased significantly when exogenous VEGF was applied in the form of protein or cDNA. CONCLUSION VEGF provides a new way for therapeutic angiogenesis in reparative and reconstructive surgery.
Objective To compare and evaluate the capability of pure autogenous bone and the enhanced autogenous bone combined with bone morphogenetic protein in bone repair of femoral head. Methods Eighteen femoral heads of 9 dogs weredrilled by trephine, 4 mm in diameter, followed by respective implantations of autogenous bone grafting (group B) and of the enhanced autogenous bone composite, combined with bone morphogenetic protein (group C), with the selfrepair of bone defect as the control (group A). Three, six, nine weeks after the operation, radiological examination, computerized tomography, light and electronic microscopes were performed to investigate the bone healing of the defect in the femoral head. Results In group A, it could be observed that there washematoma organization and delayed woven bone formation in the 3rd week after operation, and therewas little replacement of woven bone by bone trabecula in the 9th week; in group B, the autogenous bone implanted were dead in the 3rd week and maintained in situ in the 9th week; in group C, active new bone formation, either endochondral or intramembranous ossification, was found in the 3rd week and entire repair of the bone defect by bone trabecula in the 9th week after operation. Conclusion The enhanced autogenous bone combined with bone morphogenetic protein could promote reconstruction of the bone defect in femoral head, superior to pure autogenous bone which could provide a framework for the new bone formation.
Objective To study the relationships between expressions of somatostatin receptor subtypes（SSTR1-SSTR5） and angiogenesis in colorectal cancer. Methods The expressions of SSTR1-SSTR5, VEGF, and CD34 in the paraffin sections of colorectal cancer tissues from 127 cases were detected by the standard streptavidin-peroxidase (SP) technique. CD34 was used as a marker to account microvessel density (MVD) in colorectal cancer tissues. The relationships between the expressions of SSTR1-SSTR5 and VEGF expression, or MVD were analyzed. Results The positive expression rate of SSTR1, SSTR2, SSTR3, SSTR4, and SSTR5 was 64.6% （82/127）, 36.2% （46/127）, 18.9% （24/127）, 18.9% （24/127）, and 38.6% （49/127） in colorectal cancer tissues, meanwhile, the positive expression rate of VEGF was 63.8% （81/127） and MVD was (34.67±16.62)/HP in colorectal cancer tissues. The positive expression rate of VEGF (47.8%， 22/46) and MVD 〔(29.00±15.32)/HP〕 in colorectal cancer tissues with SSTR2 positive expression were significantly lower than those in colorectal cancer tissues with SSTR2 negative expression 〔72.8%， 59/81； (37.90±16.56)/HP〕, Plt;0.05. There were no relationships between SSTR1, SSTR3, SSTR4, and SSTR5 expression and VEGF expression or MVD （Pgt;0.05）. Conclusion The positive expression of SSTR2 is related with angiogenesis in colorectal cancer tissues.