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.
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)
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: To study the effect of simvastatin on the expression of bone morphogenetic protein-2 (BMP-2) and alkaline phosphates (ALP) activity in the primary cultured bone marrow stromal cells, and to elucidate the mechanism of the anabolic osteogenetic effect of simvastatin. METHODS: Bone marrow stromal cells in femur and tibia of adult mouse were cultured in vitro. after treated with different concentrations of simvastatin (0, 0.1, 0.2, 0.5 and 1.0 mumol/L) or recombinant human BMP-2 for 72 hours, ALP activity of bone marrow stromal cells was determined. BMP-2 expression of bone marrow stromal cells was analyzed by using immunocytochemistry and Western blotting. RESULTS: After treated with simvastatin for 72 hours, BMP-2 expression increased, while little BMP-2 expression could be observed in the control group. ALP activity also increased in a dose-dependent manner; t-test showed that ALP activity in the group which concentrations of simvastatin were 0.5 mumol/L (t = 2.35, P = 0.041), 1.0 mumol/L (t = 2.348, P = 0.041) had significant difference when compared with control group. CONCLUSION: Simvastatin lead to high expression of BMP-2 in bone marrow stromal cells, via the increased auto- or para-crine of BMP-2, and ALP activity increased. These may be parts of the mechanism on the anabolic osteogenetic effect of simvastatin.
Schwanns cells were obtained from the distal end of the sciatic nerve following Wallerian degeneration of SD rats. These cells were cultured with the anteriorhorn neuron of spinal cord of 14dayold SD rat fetus. The two kinds of cells were separated by a slice. Through the microscope, the dendrites and the morphology changes at the 24th, 48th, 72th, and 96 th hour after culture were observed. It was demonstrated that the Schwanns cells played the role of maintaining the survival of neuron and promoting the growth of dendrites. It was said that the Schwanns cells could secrete neurotrophic factor which made the body enlarged and caused the dendrites enlonged to several times of the body.
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）
In order to observe the role of genetically modified Schwann cell (SC) with pSVP0Mcat in the regeneration of injured spinal cord, the cells were implanted into the spinal cord. Ninety SD rats were used to establish a model of hemi-transection of spinal cord at the level of T8, and were divided into three groups, randomly, that is, pSVP0Mcat modified SC implantation (Group A), SC implantation (Group B) and without cell implantation as control (Group C). After three months the presence of axonal regeneration of the injured spinal cord was examined by means of horseradish peroxidase (HRP) retrograde labelling technique and stereography. The results indicated that HRP labelled cells in Group A and B could be found in the superior region of injured spinal cord and the brain stem such as the red nuclei and oculomotor nuclei. The density of ventral hom neurons of the spinal cord and the number of myelinated axons in 100 microns of the white matter was A gt; B gt; C group. In brief, the pSVP0Mcat modified SC intraspinal implantation could promote regeneration of the injured spinal cord.
PURPOSE:Understanding the characteristics of color vision defects in patients with maculopathy. METHODS:Applying Panel D-15 test and FM 100-hue test to evaluate the color vision of 78 patients (122 eyes) with maculopathy and analyzing the types of color vision defects and the relationship between the color discrimination and the visual acuity. RESULTS:All eyes of the wetform AMT(14 eyes),Stargardt's disease(10 eyes),macular hole (6 eyes)and central exudative retinochoroidopathy(3 eyes)showed color vision defects and high average roots of total error scores of FM 1000-hue test.The abnormal rates of color vision and the average roots of tota error scores in patients with epiretinal membrane (18 eyes)and dry-form AMD(71 eyes)were low.The roots of total error scores in FM 100-hue test was negatively relative with the visual acuity（r-0.8944）. CNCLUSION:The types and severities of color vision defects vary in different maculopathy.The color discrimination was negatively relative with the visual acuity. （Chin J Ocul Fundus Dis,1996,12: 80-82）
ObjectiveTo study the local vascular remodeling, inflammatory response, and their correlations following acute spinal cord injury (SCI) with different grades, and to assess the histological changes in SCI rats.MethodsOne hundred and sixteen adult female Sprague Dawley rats were randomly divided into 4 groups (n=29). The rats in sham group were received laminectomy only. A standard MASCIS spinal cord compactor was applied with drop height of 12.5, 25.0, or 50.0 mm to establish the mild, moderate, or severe SCI model, respectively. Quantitative rat endothelial cell antigen 1 (RECA1) and CD68 positive areas and the correlations were studied by double immunofluorescent (DIF) staining at 12 hours, 24 hours, 3 days, 7 days, and 28 days following SCI. Moreover, qualitative neurofilament-H (NF-H) and glial fibrillary acidic protein (GFAP) positive glial cells were studied by DIF staining at 28 days. ELISA was used to detect the levels of tumor necrosis factor α (TNF-α), interleukin 1β (IL-1β), and IL-6 in spinal cord homogenates at 12 hours, 24 hours, and 3 days, and the correlations between TNF-α, IL-1β, or IL-6 levels and microvascular density (RECA1) were accordingly studied. Moreover, the neural tissue integrity and neuron damage were assessed by HE staining at 12 hours, 24 hours, 3 days, 7 days, and 28 days, and Nissl’s staining at 28 days following SCI, respectively.ResultsDIF staining revealed that the ratio of RECA1 positive area was the highest in moderate group, higher in mild and severe groups, and the lowest in sham group with significant differences between groups (P<0.05). The ratio of CD68 positive area was the highest in severe group, higher in moderate and mild groups, and the lowest in sham group with significant differences between groups (P<0.05), except the comparisons between mild and moderate groups at 24 hours and 28 days after SCI (P>0.05). There was no significant correlation between the RECA1 and CD68 expressions in sham group at different time points (P>0.05). At 12 and 24 hours after SCI, the RECA1 and CD68 expressions in mild and moderate groups showed significant positive correlations (P<0.05), while no significant correlation was found in severe group (P>0.05). No significant correlations between the RECA1 and CD68 expressions was shown in all SCI groups at 3 days and in severe group at 7 days (P>0.05), while the negative correlations were shown in mild and moderate groups at 7 days, and in all SCI groups at 28 days (P<0.05). In mild, moderate, and severe groups, the axons became disrupted, shorter and thicker rods-like, or even merged blocks with increased injury, while the astrocytes decreased in number, unorganized and condensed in appearance. ELISA studies showed that TNF-α, IL-1β, and IL-6 levels in sham group were significantly lower than those in other 3 groups at different time points (P>0.05). The differences in TNF-α, IL-1β, and IL-6 levels between SCI groups at different time points were sinificant (P<0.05), except IL-1β levels between the mild and moderate groups at 12 hours (P>0.05). Three inflammatory factors were all significantly correlated with the microvascular density grades (P<0.05). Histological analysis indicated that the damage to spinal cord tissue structure correlated with the extent of SCI. In severe group, local hemorrhage, edema, and infiltration of inflammatory cells were found the most drastic, the grey/white matter boundary was disappeared concurrently with the formation of cavity and shortage of normal neurons.ConclusionIn the acute stage following mild or moderate SCI, progressively aggravated injury result in higher microvessel density and increased inflammation. However, at the SCI region, the relation between microvessel density and inflammation inverse with time in the different grades of SCI. Accordingly, the destruction of neural structures positively relate to the grades of SCI and severity of inflammation.