Myelin formation is considered the last true "invention" in the evolution of vertebrate nervous system cell structure. The rapid jumping pulse propagation achieved by myelin enables the high conduction speed that is the basis of human movement, sensation, and cognitive function. As a key structure in the brain, white matter is the gathering place of myelin. However, with age, white matter-associated functions become abnormal and a large number of myelin sheaths undergo degenerative changes, causing serious neurological and cognitive disorders. Despite the extensive time and effort invested in exploring myelination and its functions, numerous unresolved issues and challenges persist. In-depth exploration of the functional role of myelin may bring new inspiration for the treatment of central nervous system (CNS) diseases and even mental illnesses. In this study, we conducted a comprehensive examination of the structure and key molecules of the myelin in the CNS, delving into its formation process. Specifically, we propose a new hypothesis regarding the source of power for myelin expansion in which membrane compaction may serve as a driving force for myelin extension. The implications of this hypothesis could provide valuable insights into the pathophysiology of diseases involving myelin malfunction and open new avenues for therapeutic intervention in myelin-related disorders.
Myelin Sheath/metabolism* ; Humans ; Central Nervous System/metabolism* ; Animals

Objective:To explore the impact of donor cold ischemia time(CIT)on early recovery after liver transplantation(LT).Methods:From January 2016 to December 2020, the relevant clinical data were retrospectively reviewed for 456 LT recipients.According to the value of CIT of donor liver, they were assigned into two groups of CIT >5 h and CIT≤5 h. T, Mann-Whitney U or Chi square test was employed for statistical processing.Intraoperative findings and liver function(LF)parameters of two groups were compared, including operative duration, intraoperative volume of hemorrhage, erythrocyte transfusion and anhepatic phase.LF parameters included alanine aminotransferase(ALT), aspartate aminotransferase(AST)and total bilirubin(TB)within Day 1-7 post-LT.Postoperative recovery was evaluated by postoperative stay of intensive care unit(ICU), normalization time of liver function recovery, length of postoperative hospitalization and incidence of postoperative complications.Results:Among them, 407(89.3%)patients underwent classic orthotopic LT.Median CIT of donor liver was 309 min.In CIT≤5 h and CIT >5 h groups, operative duration was[(446.3+ 76.8)vs.(526.0+ 98.1)min], anhepatic phase time[(51.9+ 13.3)vs.(62.6+ 18.9)min]and intraoperative volume of erythrocyte transfusion[(7.3+ 5.8)vs.(10.0+ 6.87)U]. And the differences were statistically significant( P<0.001, 0.001 & 0.001). Postoperative hospitalization stay was longer[(29.1±15.9)vs.(27.1±13.0)]day.And the incidence of postoperative complications was higher in CIT >5 h group[22.7%(54/238)vs.12.4%(27/218)]. And the difference was statistically significant( P=0.045 & 0.004). As compared with CIT≤5 h group, ALT, AST & TB spiked in CIT >5 h group at Day 1 post-operation and the differences were statistically significant( P=0.002, P<0.001, P=0.001). In CIT >5 h group, ALT rose at Day 2/5/6/7 post-LT( P=0.026, 0.026, 0.015 & 0.011), AST jumped from Days 2-6( P=0.002, 0.004, 0.035, 0.029 and 0.019)and TB increased from Days 2-7 post-LT and the differences were statistically significant( P=0.003, 0.014, 0.030, 0.039, 0.027 & 0.009). LF recovered at CIT≤5 h and CIT>5 h group[(10.0±3.2)vs.(10.7±3.3)day]. There were significantly statistical differences( P=0.044). Conclusions:Non-conducive to patient recovery, prolonged cold ischemic time aggravates early LF injury post-LT.

Objective To investigate radiation doses to examinees undergoing computed tomography (CT) scanning of different body parts (the head, chest, and abdomen) in medical institutions of Shijiazhuang, China, and to provide a reference for optimizing radiation protection for examinees in medical institutions. Methods March 2021 to March 2022, eleven medical institutions of radiation monitoring in Shijiazhuang were surveyed for the basic information, scanning parameters, and dosimetric data of a total of 930 adults and children who received CT examinations. The dosimetric data of the subjects were analyzed and compared with the domestic and international diagnostic reference levels and the results of other cities in China. Results In the above hospitals, the CTDI_vol(P₅₀) of CT subjects in children's group were 17.42-50.45 mGy, 2.13-14.01 mGy and 3.58-28.20 mGy, respectively. DLP(P₅₀) ranges from 228.87 to 966.97 mGy·cm, 33.20 to 296.03 mGy·cm, and 74.90 to 926.53 mGy·cm, respectively. In the adult group, the CTDI_vol(P₅₀) in the head, chest and abdomen of CT subjects were 37.28-54.05 mGy, 6.43-14.99 mGy and 8.28-18.75 mGy, respectively. DLP(P₅₀) ranges from 372.81 to 630.56 mGy·cm, from 219.77 to 467.93 mGy·cm, and from 313.86 to 689.87 mGy·cm, respectively. The distribution of radiation doses in different-grade hospitals varied greatly. The abdomen dose of the children's hospital was higher than other hospitals. Especially the primary hospitals were significantly higher than the recommended diagnostic reference level (DRL). Conclusion In some secondary and primary hospitals, the setting of CT scanning parameters was simplified, not specific to the subjects’ age and body types. They should strictly comply with the principal of optimizing radiation protection to strengthen radiation dose optimization and supervision, reducing the radiation dose of examinees in future examinations .

MicroRNA (miRNA) is a short noncoding RNA, which can regulate gene expression.miR-21 is one of the human miRNAs identified earlier.As an oncovirus, it is involved in the post-transcriptional regulation of gene and plays important roles in cell proliferation, apoptosis and differentiation.In addition, miR-21 promotes inflammatory responses and also plays a key role in regulating the function of immune system.Recent studies have shown that miR-21 could be detected in corneal fibroblasts cells, retinal pigment epithelial cells, retinal microvascular endothelial cells, retinal microglia and other eye-derived cells.Furthermore, miR-21 plays an important part in the development of various eye diseases including retinoblastoma, uveal melanoma, corneal alkali burn, proliferative vitreoretinopathy, diabetic retinopathy and uveitis.Further studies have shown that inhibited expression of miR-21 can treat retinoblastoma and rescue vision loss caused by corneal neovascularization and diabetic retinopathy, while overexpression of miR-21 can promote corneal epithelial healing and treat primary open-angle glaucoma and retinal degeneration.This review summarized the recent research progress of the role of miR-21 in eye diseases.

Objective To study the different ischemic characteristics of cerebral gray matter and deep white matter in patients with chronic cerebral artery severe stenosis or occlusion. Methods A retrospective study was conducted on 30 patients with chronic unilateral cerebral artery severe stenosis or occlusion from April 2014 to April 2018 in our hospital. Cerebral blood flow (CBF), cerebral blood volume (CBV), mean transit time (MTT), time of peak time (TTP) and time to delay(TTD) of cerebral cortex gray matter and deep white matter in the blood supply area of the responsible artery (the affected side) and the contralateral hemisphere (the healthy side) were measured. Statistical analysis of the perfusion parameters of cerebral cortex gray matter and deep white matter in the affected side and contralateral side were performed using SPSS13.0 software package. T test was used for variance homogeneity, and t′test was used for variance discrepancy, and P<0.05 was statistically significant. Results The average values of CBF and CBV of the ipsilateral and contralateral cerebral cortex were increased than those of ipsilateral and contralateral cerebral deep white matter respectively(P<0.01). MTT, TTP and TTD of the ipsilateral and contralateral cerebral cortex were decreased than that of ipsilateral and contralateral cerebral deep white matter (P<0.01); CBF of ipsilateral cerebral cortex and CBV of ipsilateral cerebral deep white matter were not different from those of the contralateral cerebral cortex and deep white matter respectively, but CBF of ipsilateral cerebral deep white matter is decreased than that of the contralateral deep white matter (P<0.01). CBV of ipsilateral cerebral cortex is increased than that of the contralateral cerebral cortex (P<0.01). MTT, TTP and TTD of ipsilateral cerebral cortex and deep white matter were increased than those of contralateral cerebral cortex and deep white matter respectively(P<0.01). Conclusion Deep cerebral white matter perfusion decreased more significantly than cortical gray matter in the supply region of chronic cerebral artery severe stenosis or occlusion. CT perfusion imaging can quantify the degree of chronic cerebral ischemia and can provide quantitative diagnostic information for clinical treatment and efficacy evaluation.

Objective: To study the different ischemic characteristics of cerebral gray matter and deep white matter in patients with chronic cerebral artery severe stenosis or occlusion. Methods: A retrospective study was conducted on 30 patients with chronic unilateral cerebral artery severe stenosis or occlusion from April 2014 to April 2018 in our hospital. Cerebral blood flow (CBF), cerebral blood volume (CBV), mean transit time (MTT), time of peak time (TTP) and time to delay(TTD) of cerebral cortex gray matter and deep white matter in the blood supply area of the responsible artery (the affected side) and the contralateral hemisphere (the healthy side) were measured. Statistical analysis of the perfusion parameters of cerebral cortex gray matter and deep white matter in the affected side and contralateral side were performed using SPSS13.0 software package. T test was used for variance homogeneity, and t′ test was used for variance discrepancy, and P<0.05 was statistically significant. Results: The average values of CBF and CBV of the ipsilateral and contralateral cerebral cortex were increased than those of ipsilateral and contralateral cerebral deep white matter respectively(P<0.01). MTT, TTP and TTD of the ipsilateral and contralateral cerebral cortex were decreased than that of ipsilateral and contralateral cerebral deep white matter (P<0.01); CBF of ipsilateral cerebral cortex and CBV of ipsilateral cerebral deep white matter were not different from those of the contralateral cerebral cortex and deep white matter respectively, but CBF of ipsilateral cerebral deep white matter is decreased than that of the contralateral deep white matter (P<0.01). CBV of ipsilateral cerebral cortex is increased than that of the contralateral cerebral cortex (P<0.01). MTT, TTP and TTD of ipsilateral cerebral cortex and deep white matter were increased than those of contralateral cerebral cortex and deep white matter respectively(P<0.01). Conclusion Deep cerebral white matter perfusion decreased more significantly than cortical gray matter in the supply region of chronic cerebral artery severe stenosis or occlusion. CT perfusion imaging can quantify the degree of chronic cerebral ischemia and can provide quantitative diagnostic information for clinical treatment and efficacy evaluation.

Mitophagy is an essential intracellular process that eliminates dysfunctional mitochondria and maintains cellular homeostasis. Mitophagy is regulated by the post-translational modification of mitophagy receptors. Fun14 domain-containing protein 1 (FUNDC1) was reported to be a new receptor for hypoxia-induced mitophagy in mammalian cells and interact with microtubule-associated protein light chain 3 beta (LC3B) through its LC3 interaction region (LIR). Moreover, the phosphorylation modification of FUNDC1 affects its binding affinity for LC3B and regulates selective mitophagy. However, the structural basis of this regulation mechanism remains unclear. Here, we present the crystal structure of LC3B in complex with a FUNDC1 LIR peptide phosphorylated at Ser17 (pS), demonstrating the key residues of LC3B for the specific recognition of the phosphorylated or dephosphorylated FUNDC1. Intriguingly, the side chain of LC3B Lys49 shifts remarkably and forms a hydrogen bond and electrostatic interaction with the phosphate group of FUNDC1 pS. Alternatively, phosphorylated Tyr18 (pY) and Ser13 (pS) in FUNDC1 significantly obstruct their interaction with the hydrophobic pocket and Arg10 of LC3B, respectively. Structural observations are further validated by mutation and isothermal titration calorimetry (ITC) assays. Therefore, our structural and biochemical results reveal a working model for the specific recognition of FUNDC1 by LC3B and imply that the reversible phosphorylation modification of mitophagy receptors may be a switch for selective mitophagy.
Crystallography, X-Ray ; Membrane Proteins ; chemistry ; metabolism ; Microtubule-Associated Proteins ; chemistry ; metabolism ; Mitochondrial Degradation ; Mitochondrial Proteins ; chemistry ; metabolism ; Peptides ; chemistry ; metabolism ; Phosphorylation ; Protein Structure, Quaternary

Objective To summarize the therapeutic effect of combined treatment for children hemifacial microsomia.Methods From Aug 2008 to May 2016, 108 children with hemifacial microsomia underwent combined treatment at an early age .Digital simultation technology was used for design of the guiding model during osteotomy .The mandibular distraction osteogenesis , auricular reconstruction and orthodontic treatment were also adopted .The maxillary development and post-distraction relapse were analyzed during the follow-up period.Results The distractor fell off in 3 cases.All other patients got obvious improvement in facial symmetry , auricular deformity and occlusion .During the follow-up period of 6 -39 months, the development of maxilla on the affected side increased significantly .Though the distracted mandible showed some certain relapse , but the facial asymmetry and occlusion improved a lot . Conclusions The children hemifacial microsomia should receive a combined treatment at an early age to achieve a goodresult .

Objective To summarize the therapeutic effect of combined treatment for children hemifacial microsomia.Methods From Aug 2008 to May 2016, 108 children with hemifacial microsomia underwent combined treatment at an early age .Digital simultation technology was used for design of the guiding model during osteotomy .The mandibular distraction osteogenesis , auricular reconstruction and orthodontic treatment were also adopted .The maxillary development and post-distraction relapse were analyzed during the follow-up period.Results The distractor fell off in 3 cases.All other patients got obvious improvement in facial symmetry , auricular deformity and occlusion .During the follow-up period of 6 -39 months, the development of maxilla on the affected side increased significantly .Though the distracted mandible showed some certain relapse , but the facial asymmetry and occlusion improved a lot . Conclusions The children hemifacial microsomia should receive a combined treatment at an early age to achieve a goodresult .

Objective To investigate the expression of oncogene C-erbB-2 and its significance in colorectal carcinoma. Methods Immunohistological EnVision staining was used to detect the expression of C-erbB-2 in 171 colorectal carcinoma, and 15 normal colorectal tissues were taken as controls. Results The positive percentages of C-erbB-2 in colorectal carcinoma and normal colorectal tissues were 23.4 % (40/171)and 0, which was significantly different (P ＜0.05). Only 5 samples showed strong positive expression (++ and +++) on epicyte, no relationship was found between C-erbB-2 expression and patients' gender, tumor differentiation, tumor stage, vascular and lymph node involvement, etc(P ＞0.05). The five year survival rate were 69.5 % (91/131) and 65.0 % (26/40) of C-erbB-2 negative and positive expression, the difference was not statistical (P ＞0.05). Conclusion There was on significant association between C-erbB-2 expression and clinicopathologic characteristics of colorectal carcinoma. C-erbB-2 did not present prognostic value in colorectal carcinoma.