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<p><b>BACKGROUND</b>Leber congenital amaurosis (LCA) is a visual disease which is caused by RPE65 mutations and results in retinal degeneration and severe vision loss in early infancy. According to previous researches, mutations of the RPE65 gene account for 16% of all cases of LCA. This study aimed to identify RPE65 gene mutations in Chinese patients with LCA.</p><p><b>METHODS</b>We recruited 52 sporadic patients from Peking University Third Hospital in 2016 and applied Sanger sequencing to identify variants among exons responsible for the disease. The genomic DNAs from blood leukocytes of these patients were isolated, and the entire coding region of the RPE65 gene was amplified by polymerase chain reaction. We then determined the sequence of RPE65 using ABI 3100 Genetic Analyzer.</p><p><b>RESULTS</b>Our study identified that only 1 out of the 52 patients with LCA carried the previously unreported homozygosis missense mutation c1174A>C (T392P) of the RPE65 gene. However, the mutation was associated with the disease phenotype and not detected in 100 normal controls.</p><p><b>CONCLUSIONS</b>Though we identified a novel missense mutation in the RPE65 gene that causes LCA, our result indicates that RPE65 mutations may not play a major role in the LCA patients in China since only 1 out of the 52 patients carried mutation in the RPE65 gene.</p>
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Microglia is the most important immune cell in the central nervous system.It plays a key role in mediating the immune response in the central nervous system.Sterile inflammation is the key factor in the pathophysiological process following ischemic stroke.Microglia is activated and induces a series of inflammatory signals through binding of injuring related ligands to their corresponding receptors.This article introduces the activation of microglia and inflammatory response after ischemic stroke from Toll-like receptors,inflammasome,cytokine receptors,Notch signaling and other signaling pathways.
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Background Genetic mutation remains to be the most common cause of congenital cataract.Whole exon sequencing technology is an ideal method to detect the pathogenic gene mutations.Objective This study was to identify the pathogenic gene in a Chinese autosomal dominant congenital cataract (ADCC) family by whole-exome sequencing.Methods This study complied with Helsinki Declaration and the protocol was approved by Ethic Committee of Peking University Third Hospital.Informed consent was obtained from each subject before any medical examination.A cross-sectional study was designed.A Chinese ADCC family with 4 generations and 48 members were enrolled in Peking University Third Hospital,of which Ⅰ1 and Ⅰ2 died.The periphery blood of 8-10 ml was collected from each member of Ⅱ,Ⅲ and Ⅳ generations for the high throughput sequencing of genes using whole exon trapping and new sequencing technology,and the sequencing results were compared with the data of human HA PMAP8,dbSNP130 and 1000 Genome Project database.The synonymous mutation was filtered after reported common variants,and the false positive results of explicit sequencing were finally excluded by Sanger sequencing and then the candidate genes were identified.The mutation genes were screened to determine the pathogenic gene of this ADCC family.Results Eleven ADCC patients were found in this family,and the patients distributed in each generation with an equal chance for involvement in male and female subjects,which conformed to an autosomal dominant inheritance pattern.All the patients were nuclear cataract.Genome-wide whole-exome sequencing found that major intrinsic protein (MIP) gene was known genes of ADCC in initially identified candidate genes,so the Sanger was used to verify the MIP gene.The heterozygous mutation of MIP gene (chr12:56845250 C ＞ T) appeared to be the pathogenic cause of this ADCC family.The mutation occurred in the splice sites of the gene,resulting in the fourth exon coded-61 amino acids are replaced by leucine,histidine and serine,which lead to the abnormal truncated proteins.Conclusions The heterozygous mutation of MIP gene is the molecular pathogenesis of this Chinese ADCC family.
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Objective To investigate the effects of of inhibition of AMP-activated protein kinase (AMPK) on cytochrome c (CytC) expression in the cortex and hippocampus after focal cerebral ischemia-reperfusion in mice. Methods Thirty-six male C57BL/6 mice were randomly divided into 3 groups: a sham operation group, an ischemia-reperfusion group, and a compound C group (n = 12 in each group). The mice of the compound C group were intraperitonealy injected an AMPK specific inhibitor compound C (20 mg/kg) at the time of ischemia. A model of middle cerebral artery occlusion was induced by a modified suture method. After 24 h of reperfusion, Western blot was used to detect the expression levels of AMPK, phosphorylated-AMPK (p-AMPK), and cytoplasm CytC in the cortex and hippocampus in the ischemic side. Results p-AMPK/MPK levels in the cortex in the sham operation group, ischemia-reperfusion group, and compound C group were 0. 701 ± 0. 197, 1. 408 ± 0. 322, and 0. 930 ± 0. 229, respectively (F = 12. 000, P =0. 001); p-AMPK/MPK levels in the hippocampus were 0. 685 ± 0. 228, 1. 507 ± 0. 418, and 0. 964 ± 0. 378, respectively ( F = 8. 530, P = 0. 003 ); p-AMPK/AMPK levels both in the cortex ( P < 0. 001 ) and hippocampus (P = 0. 001) in the ischemia-reperfusion group were significantly higher than those in the sham operation group, p-AMPK/AMPK levels both in the cortex (P = 0. 005) and hippocampus (P = 0. 017) in the compound C group were significantly lower than those in the ischemia-reperfusion group. CytC levels in the cortex in the sham operation group, ischemia-reperfusion group, and compound C group were 0. 496 ±0. 278, 1. 461 ± 0. 321, and 1. 018 ± 0. 175, respectively (F = 19. 915, P < 0. 001); CytC levels in the hippocampus were 0. 511 ± 0. 257, 1. 610 ± 0. 441, and 0. 921 ± 0. 228 (F = 17. 795, P < 0. 001); CytC levels both in the cortex (P < 0. 001) and hippocampus (P < 0. 001) in the ischemia-reperfusion group were significantly higher than those in the sham operation group, while CytC levels both in the cortex (P = 0. 011) and hippocampus (P = 0. 002) in the compound C group were significantly lower than those in the ischemia-reperfusion group. Conclusion Inhibition of the AMPK may down-regulate the cytoplasm CytC expression in the cortex and hippocampus after cerebral ischemia-reperfusion in mice.
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<p><b>OBJECTIVE</b>To investigate potential mutation of PHOX2A (or ARIX) gene in a Chinese family affected with congenital fibrosis of extraocular muscles tyep 2 (CFEOM2).</p><p><b>METHODS</b>Genomic DNA was obtained from affected and unaffected members of the family. With an ABI PRSIM Linkage Mapping Set-MD10 kit, selected markers flanking the PHOX2A locus were used for linkage analysis. Exons of PHOX2 gene were amplified and sequenced. A total of 100 normal subjects were recruited as controls.</p><p><b>RESULTS</b>Genetic linkage was found at 11q13 between D11S4151 and D11S1320 and the PHOX2A gene. DNA sequencing has identified a heterozygous mutation in the exon 2 of the gene (227T to G, N76K). The same mutation was not found in the unaffected and 100 normal controls.</p><p><b>CONCLUSION</b>A mutation of the PHOX2A gene 227T to G is responsible for the onset of congenital fibrosis of extraocular muscles type 2 in this Chinese family.</p>
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Female , Humans , Male , Base Sequence , Case-Control Studies , China , Fibrosis , Genetics , Homeodomain Proteins , Genetics , Molecular Sequence Data , Mutation , Ocular Motility Disorders , Genetics , Oculomotor Muscles , Congenital Abnormalities , PedigreeABSTRACT
Objective To investigate the effects of Saussurea involucrata extract pretreatment on the expression of the Toll-like receptor 4 (TLR4)/nuclear factor-κB (NF-κB) in focal cerebral ischemia/reperfusion in mice and its possible neuroprotective mechanism.Methods Seventy-two Kunming mice were randomly divided into four groups:sham operation,saline,Saussurea involucrata extract,and edaravone groups (n =18 in each group).Saussurea involucrata extract 0.8 g/kg was given intraperitoneally in the Saussurea involucrata extract group; edaravone 3 mg/kg was given in the edaravone group; and the same volume of saline was given in the saline group.A model of middle cerebral artery occlusion (MCAO) was induced after 7 days of continuous injection.Cerebral infarct volume was determined by 2,3,5-triphenyltetrazolium staining.Immunohistochemical staining was used to detect TLR4-positive cells in ischemic brain tissue.Reverse transcriptase polymerase chain reaction was used to detect the expression of TLR4/NF-κB mRNA.Results The cerebral infarct volume in mice in the saline,Saussurea involucrata extract and edaravone groups was 131.55± 28.25 mm3,84.10 ±13.92 mm3 and 65.10 ± 6.78 mm3,respectively.There were significant difference (F =10.158,P =0.012).The infarct volume in the Saussurea involucrata extract group (P =0.020) and edaravone group (P0.005) was significantly less than that in the saline group,and there was no significantly difference between the 2 groups.The numbers of cortex and TLR4 positive cells in hippocampus area at the ischemic sides in the saline group were significantly more than those in the sham operation group (all P ＜0.001).The numbers of positive cells of cortex and TLR4 in the Saussurea involucrata extract group and the edaravone group were significantly decreased compared to the saline group (all P ＜ 0.05),and there was no significant differences between the Saussurea involucrata extract group and the edaravone group.The expressions of TLR4,p50,and p65 mRNA in the saline group were significantly up-regulated compared to the sham operation group (all P =0.000).Saussurea involucrata extract could significantly down-regulate the expressions of TLR4,p50,and p65 mRNA at 24 hours after ischemia/reperfusion (all P =0.000).Edaravone could significantly down-regulate the expressions of TLR4 and p65 mRNA (all P =0.000) and it had a down-regulated trend for the expression of p50 mRNA (P =0.053); while there was no significant difference in the expressions of TLR4 and p65 mRNA between the Saussurea involucrata extract group and the edaravone group.Conclusions Saussurea involucrata extract pretreatment may significantly reduce the cerebral infarct volume,down-regulate the expressions of TLR4 and NF-κB subunit,and play a neuroprotective effect by inhibiting inflammatory response after ischemia.
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<p><b>OBJECTIVE</b>To map the candidate gene by linkage analysis in a Chinese family with autosomal dominant congenital retinaochoroidal coloboma.</p><p><b>METHODS</b>A detailed clinical examination was performed for all patients in the family. The genomic DNA of all family members was extracted from peripheral blood leukocytes. Linkage analysis and genome-wide linkage screening was conducted using fluorescent detection of 398 microsatellite markers representing all autosomes at an average resolution of approximately 10 cM. Polymerase chain reaction was carried out to amplify all 398 microsatellite markers. The allele sizes were determined on ABI 3130-Avant genetic analyzer according to an internal size standard, and the results were analyzed using Genescan 3.1 and Genotyper 2.0 software.</p><p><b>RESULTS</b>Linkage analysis showed the markers D2S2382-D2S301-D2S2244-D2S163 co-segregated with the disease locus in all affected members. The maximum Lod score was 3.01(D2S2382).</p><p><b>CONCLUSION</b>The candidate region of the disease gene in the family was located in 2q34-2q35.</p>
Subject(s)
Female , Humans , Male , Asian People , Chromosome Mapping , Coloboma , Genetics , DNA Mutational Analysis , Family , Genetic Linkage , Genotype , Lod Score , Loss of Heterozygosity , Microsatellite Repeats , Genetics , Myopia , Genetics , Pedigree , Polymerase Chain ReactionABSTRACT
0.05).Con- clusion It is a feasible way for infants to fast in solid diet 6 hours and liquid 2 hours before operation in order to re- duce indisposition of infants and meet the need of operation.