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)
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.
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.
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 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.
Schwanns cell (SC) was isolated from sciatic nerve of adult rat with Wallerine degeneration. After culture, SC-serum free culture media (SCSFCM) was obtained. By ultrafiltration with PM-10 Amicon Membrane, electrophoresis with DiscPAGE,and electrical wash-out with Biotrap apparatus, D-band protein was isolated from the SC-SFCM. The D-band protein in the concentration of 25ng/ml could affect the survival of the spinal anterior horn neuron in vitro, prominently and itsactivity was not changed after being frozen. The molecular weight of the protein ranged from 43 to 67 Kd. The D-band protein might be a neurotrophic substancedifferent from the known SCderived neurotrophic factors (NTF). Its concentration with biological activity was high enough to be detected. The advantages of MTT in assessment of NTF activity were also discussed.
Objective To investigate the heterotopic odontogenesis ability ofDelta1 gene transfected human dental pulp stem cell (DPSC) and nanohydroxyapatite/collagen (nHAC) composite scaffold. Methods The cultured human DPSC was transfected with Delta1-enhanced green fluorescent protein recombinant retrovirus supernatant，and was selected by puromycin to obtain the positive cell clone. The experimental group contained the Delta1 transfected DPSC; however, the control group did not contain the Delta1 transfected DPSC but contained DPSC transfected with vectors only. The cells were seeded into the nHAC carriers and were cultured in the odonto-inductive medium. The growth of the transduced cells in the carriers was observed by the fluorescent phase contrast microscope and the scanning electron microscope (SEM). The cell-carrier composites were subcutaneously transplanted into the Delta1 transfected 8 nude mice (female, 8 weeks old). Eight weeks after operation,the composites were taken out and tested with the histological and the immunohistological methods.Results Green fluorescence was observed inthe cells in the experimental group, which were grown in the carriers by the fluorescent phase contrast microscope. Observed by SEM, great amounts of transduced DPSC were observed along the scaffold materials, even filling the porous structures of nHAC and secreting a lot of extracellular matrix. However, in the control group, much fewer cells were found in the carriers. All the 4 Delta1 transduced DPSC-nHAC composites produced dentin-like structures that lined the surfaces of some nHAC porous structures. The odontoblast-like cells extended the cytoplasmic processes into the dentinal matrix, which was interfaced with a pulp-like interstitial tissue infiltrated with the blood vessels. Dentin sialophosphoprotein was expressed in the odontoblast-like cells when immunohisochemistry was performed. The morphology of the control composite was a typical one of the fibrous connective tissue,and only a little dentin-like structure was found in 2 of the 8 control transplants. Conclution DPSC can be used as the recipient cell of the Delta1 gene for expression and secretion of the Delta1 protein. The composites of the transfected cells and nHAC can induce heterotopic odontogenesis, which indicates that Delta1 is a novel candidate for the gene enhanced dentinpulp composite engineering.
Objective To analyse the indocyanine green angiographic findings in contralateral eyes of patients with unilateral exudative age-related macular degeneration(AMD). Methods Fundus photograph,fundus fluorescein angiography(FFA) and indocyanine green angiography(ICGA) were performed in a series of 70 patients with unilateral AMD and drusens and pigmentary changes in the macular region in contralateral eyes.The findings of fluoroangiograms were observed and analysed. Results ICGA revealed the characteristics of the contralateral eyes as follows:(1)Drusen could be hypofluorescent,hyperfluorescent or normal fluorescent;(2)14 eyes revealed plaque-like late hyperfluorescent;(3)13 eyes revealed choroidal filling defect;(4)18 eyes revealed pindot-like clusters of late hyperfluorescence. Conclusion ICGA is useful in evaluating the lesions and circulation disturbance of the contralateral eye,and may help to find the risk factors of developing future exudative changes. (Chin J Ocul Fundus Dis, 1999, 15: 216-218)
ObjectiveTo determine the expression level of Sonic hedgehog (Shh) in the passage of hair follicle stem cells (HFSCs), analyze the effect of Shh overexpression on the proliferation activity of HFSCs, and explore the survival of HFSCs after Shh overexpression and its effect on hair follicle regeneration. MethodsHair follicles from the normal area (H1 group) and alopecia area (H2 group) of the scalp donated by 20 female alopecia patients aged 40-50 years old were taken, and the middle part of the hair follicle was cut under the microscope to culture, and the primary HFSCs were obtained and passaged; the positive markers (CD29, CD71) and negative marker (CD34) on the surface of the fourth generation HFSCs were identified by flow cytometry. The two groups of HFSCs were transfected with Shh-overexpressed lentivirus. Flow cytometry and cell counting kit 8 assay were used to detect the cell cycle changes and cell proliferation of HFSCs before and after transfection, respectively. Then the HFSCs transfected with Shh lentivirus were transplanted subcutaneously into the back of nude mice as the experimental group, and the same amount of saline was injected as the control group. At 5 weeks after cell transplantation, the expression of Shh protein in the back skin tissue of nude mice was detected by Western blot. HE staining and immunofluorescence staining were used to compare the number of hair follicles and the survival of HFSCs between groups. ResultsThe isolated and cultured cells were fusiform and firmly attached to the wall; flow cytometry showed that CD29 and CD71 were highly expressed on the surface of the cells, while CD34 was lowly expressed, suggesting that the cultured cells were HFSCs. The results of real-time fluorescence quantitative PCR and Western blot showed that the expression levels of Shh protein and gene in the 4th, 7th, and 10th passages of cells in H1 and H2 groups decreased gradually with the prolongation of culture time in vitro. After overexpression of Shh, the proliferation activity of HFSCs in the two groups was significantly higher than that in the blank group (not transfected with lentivirus) and the negative control group (transfected with negative control lentivirus), and the proliferation activity of HFSCs in H1 group was significantly higher than that in H2 group before and after transfection, showing significant differences (P<0.05). At 5 weeks after cell transplantation, Shh protein was stably expressed in the dorsal skin of each experimental group; the number of hair follicles and the expression levels of HFSCs markers (CD71, cytokeratin 15) in each experimental group were significantly higher than those in the control group, and the number of hair follicles and the expression levels of HFSCs markers in H1 group were significantly higher than those in H2 group, and the differences were significant (P<0.05). ConclusionLentivirus-mediated Shh can be successfully transfected into HFSCs, the proliferation activity of HFSCs significantly increase after overexpression of Shh, which can secrete and express Shh continuously and stably, and promote hair follicle regeneration by combining the advantages of stem cells and Shh.