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 observe the heart anatomic and histological structure of the Banna mini-pig inbred-lined and to provide the morphological data for heart xenotransplantation and breeding transgens pig. METHODS: Ten Banna mini-pigs (12-18 months old) were affused and fixed by common coratid artery. The heart were observed and measured by gross anatomy and histology. RESULTS: There were many similarities between the Banna pig heart and the human heart in anatomy and histology. However, the following differences were observed in the Banna pig heart: 1. Azygos vein directly drew into right atrium cordis. 2. The intercalated disk of cardiac muscle was less than that of human. 3. The Purkinje’s fibre was bigger than that of human. CONCLUSION: On the morphology and histology, the structure of Banna pig heart is similar to the heart of human being. It is possible that Banna minipig heart becomes organ donors for xenotransplantation.
OBJECTIVE: To explore the kidney anatomic structure of banna minipig inbred-lines, and to provide data for kidney xenotransplantation. METHODS: The fresh and infused kidneys of banna minipig (including the vessel and the ureter) were checked by anatomic microscope and vernier caliper in original location and away body. The tissue structure was observed by HE stain. RESULTS: The structure of kidney of banna minipig inbred-lines (including the vessel and the ureter) are similar to that of human being. The fascia propria of kidney is divided into three layers including capsula fibrosa, capsula adipose and fascia renalis. The thickness of cortex renalis is (20.0 +/- 2.4) mm. The average diameter of renal artery is 5.1 mm and is similar to that of human being. All the kidneys of banna minipig inbred-lines have a single branch renal artery. The diameters of left and right ureters are 5.1 mm and 4.7 mm, respectively. CONCLUSION: The kidney of banna minipig inbred-lines is an ideal replacement of human kidney for xenotransplantation.
Epigenetics refers to the changes in gene expression level and function caused by non-genetic sequence changes. It can provide the time, location and mode of the genetic information for the execution of DNA sequences, including DNA methylation, histone modification, non-coding RNA and chromatin remodeling. Studies had shown that epigenetics plays an important role in the development of diabetic retinopathy (DR), and it had been found that epigenetic-related treatment regimens had a certain effect on the treatment of DR through animal experiments and in vitro experiments. It was benefit to regulate the development of diabetes and its complications by depth study of DNA methylation, histone modification, miRNA and metabolic memory. An understanding of changes in gene transcriptional mechanisms at the epigenetic level could help us to further study the prevention and control of diabetes and its complications, and to provide new ideas for treatment.
The effects of various receptor agonists/antagonists on the accumulation of inositol phosphates(InsPs) in cultured rat retinal pigment epitheium (RPE) cells were analysed. The results showed that serotonin and the 5-HT2 agonists such as alpha;-methyl-serotonin, quipazine, and DOI (1-[2.5-dimethoxy-4-iodopheny1]-2-aminopropane) all stimulated InsPs accumulation in rat RPE cells. The serotonin-induced stimulation of InsPs was effectively blocked by ketanserin, a 5-HT2 antagonist, but also attenuated by the active phorbol ester PMA (4ft-phorbol 12-myristate 13-acetate), a potent protein kinase C activator.The data presented provide clear evidence for the presence of 5-HT2 receptors coupled to phosphoinositide metabolism on cultured rat RPE cells. （Chin J Ocul Fundus Dis,1994,10:80-83）
OBJECTIVE: To evaluate the clinical result of repairing degloving injury of hand with abdominal bipedicled subdermal vascular-network flap in emergence. METHODS: From 1994 to 1997, 19 cases with degloving injury of hand were treated with two flaps, one flaps with the inferior epigastric artery as pedicle, another with superficial epigastric artery. The two skin flaps were designed oppositely to cover the injured hands. RESULTS: All the flaps survived. Followed up for 1 to 3 years, the contour of hands were fine. Extension of fingers was normal and opponers of thumbs was good. Range of flexion of metacarpo-phalangeal joints was from 45 to 60 degrees, and the proximal interphalangeal joints was from 10 to 25 degrees. CONCLUSION: For the subdermal vascular network, the bipedicled flaps of abdomen in repair of degloving injury of hand have sufficient blood supply, b resistance to infection, high survival rate, and good contour.
ObjectiveTo investigate the difference of DNA methylation before and after bariatric surgery.MethodThe relevant literatures of the research on the changes of DNA methylation level and gene expression regulation in blood and tissues before and after bariatric surgery were retrieved and reviewed.ResultsDNA methylation was an important method of epigenetic regulation in organisms and its role in bariatric surgery had been paid more and more attention in recent years. Existing studies had found that there were changes of DNA methylation in blood and tissues before and after bariatric surgery. The degree of methylation varies with different follow-up time after bariatric surgery and the same gene had different degrees of methylation in different tissues, and some even had the opposite results.ConclusionsDNA methylation levels before and after bariatric surgery are different in different tissues. And studies with larger sample size and longer follow-up time are needed, to further reveal relationship among DNA methylation, obesity, and bariatric surgery.
ObjectiveTo observe the disease-causing genes and the inheritance in sporadic retinitis pigmentosa (sRP) in Ningxia region. Methods49 sRP patients and 128 family members were recruited for this study. All the patients and family members received complete ophthalmic examinations including best corrected visual acuity, slit-lamp microscope, indirect ophthalmoscopy, fundus color photography, visual field, optic coherence tomography, full view electroretinogram. DNA was extracted from patients and family members. Using exon combined target region capture sequencing chip to screen the 230 candidate disease-causing gene mutations, polymerase chain reaction and direct sequencing were used to confirm the disease-causing mutations. Results24/49 patients (49.0%) had identified disease-causing genes, totally 16 genes were involved. There were 41 mutation sites were found, including 32 new mutations (78.0%). The disease-causing genes include USH2A, C2orf71, GNGA1, RPGR1, IFT140, TULP1, CLRN1, RPE65, ABCA4, GUCA1, EYS, CYP4V2, GPR98 and ATXN7. Based on pedigree analysis, 20 patients were autosomal recessive retinitis pigmentosa, 3 patients were autosomal dominant retinitis pigmentosa and 1 patient was X linked retinitis pigmentosa. 3/7 patients with USH2A mutations were identified as Usher syndrome. ConclusionsUSHZA is the main disease-causing of sRP patients in Ningxia region. 83.3% of sRP in this cohort are autosomal recessive retinitis pigmentosa.
Objective To detect the expression of melanocortin 1 receptor (MC-1R) and the melanin contents in human skin autografts and the normal skin, to elucide the role of MC-1R in hyperpigmented process of skin autografts. Methods Skin autografts and normal skin samples were obtained from skin graft on neck who need reoperation to release contractures after 1 year of operations. Immunohistochemical technique was performed to detect the expression and distribution of MC-1R in skin autografts(include full thickenss skin autografts, medium thickness skin autografts, and razorthin skin autografts) and normal skin respectively. MassonFontana staining technique was performedto detect the melanin contents in all sorts specimens respectively. Results The expression of MC-1R was located on cell membrane and cytoplasm of melanocyte and keratinocyte in epidermal. The expression of MC-1R in most skin autografts was much ber than that of control normal skins; the thinnerskin autografts were, the more obvious expressions of MC-1R in skin autografts were. The expressions of MC-1R in all sorts of skinautografts were of significant differences compared with that in normal skins(P＜0.01); the expression of MC-1R in normal skin of donor area was no significant differences compared with normal skin around recipient area(P＞0.01). The contents of melanin in skin autografts were increased obviously and there were significantdifferences compared with that in normal skins(P＜0.01); the contents of melanin among all sorts of skin autografts were of significant differences (P＜0.01). The thinner skin autografts were, the more melanin contents in skin autografts. The expression of MC-1R was positively correlated with the contents ofmelanin in epidermis. Conclusion The expression of MC-1R in skin autografts is significantly higher than that in normal skin and is correlated positively with the contents of melanin in skin autografts. Overexpression of MC-1R may play an important role in hyperpigmented process of skin autografts.
OBJECTIVE: To provide an ideal method for repairing the circular cicatricial contracture of thigh. METHODS: Deep inferior epigastric perforator (DIEP) island flaps was elevated based only on the deep inferior epigastric artery and vein and transferred to cover the thigh wound after scar had been resected. RESULTS: Four DIEP island flaps was applied clinically and all flaps survived. The size of the flaps ranged from (8 cm x 28 cm) to (11 cm x 32 cm). Venous return and edema had been obviously improved postoperatively. There was no abdominal weakness and hernia in the donor sites. CONCLUSION: DIEP flap not only retains the advantages of TRAM flap such as good blood supply and rich tissue volume, but also preserves the integrity of the rectus abdominis muscle. DIEP island flap is a good material for repair of the circular cicatricial contracture of the thigh.