Cyclophilin D-induced mitochondrial impairment confers axonal injury after intracerebral hemorrhage in mice

The mitochondrial permeability transition pore is a nonspecific transmembrane channel.Inhibition of mitochondrial permeability transition pore opening has been shown to alleviate mitochondrial swelling,calcium overload,and axonal degeneration.Cyclophilin D is an important component of the mitochondrial permeability transition pore.Whether cyclophilin D participates in mitochondrial impairment and axonal injury after intracerebral hemorrhage is not clear.In this study,we established mouse models of intracerebral hemorrhage in vivo by injection of autologous blood and oxyhemoglobin into the striatum in Thy1-YFP mice,in which pyramidal neurons and axons express yellow fluorescent protein.We also simulated intracerebral hemorrhage in vitro in PC12 cells using oxyhemoglobin.We found that axonal degeneration in the early stage of intracerebral hemorrhage depended on mitochondrial swelling induced by cyclophilin D activation and mitochondrial permeability transition pore opening.We further investigated the mechanism underlying the role of cyclophilin D in mouse models and PC12 cell models of intracerebral hemorrhage.We found that both cyclosporin A inhibition and short hairpin RNA interference of cyclophilin D reduced mitochondrial permeability transition pore opening and mitochondrial injury.In addition,inhibition of cyclophilin D and mitochondrial permeability transition pore opening protected corticospinal tract integrity and alleviated motor dysfunction caused by intracerebral hemorrhage.Our findings suggest that cyclophilin D is used as a key mediator of axonal degeneration after intracerebral hemorrhage;inhibition of cyclophilin D expression can protect mitochondrial structure and function and further alleviate corticospinal tract injury and motor dysfunction after intracerebral hemorrhage.Our findings provide a therapeutic target for preventing axonal degeneration of white matter injury and subsequent functional impairment in central nervous diseases.

注水黏膜切开刀推进式内镜黏膜下剥离术切除早癌及癌前病变的应用研究

目的探讨应用注水型电刀行推进式内镜黏膜下剥离术(PESD)切除大面积贲门早癌及癌前病变的价值,并分析总结相关技术要点。方法选取2017年1月-2020年12月在保定市第一中心医院内镜诊疗中心通过胃镜活检及放大染色内镜检查考虑贲门早癌或高级别上皮内瘤变且病变最大径>2.0 cm的病例,术中用注水型电刀行PESD治疗,并选取该中心同期该医生以普通黏膜切开刀行贲门常规内镜黏膜下剥离术(ESD)治疗的病例,对比分析两组病例的单位面积剥离速度、病变完整切除率、并发症发生率(术后迟发性出血和穿孔)等。结果PESD组(n=32)病变直径2.0~8.0 cm,平均(5.1±2.9)cm;其中1处病变位于前壁,16处位于后壁,3处位于大弯侧,12处位于小弯侧;30处病变为一次性切除,2处病变(贲门大弯侧)为分块切除;剥离时间19~112 min,平均(65.5±48.3)min;术中出血8例(25.0%),无迟发性出血及穿孔发生,术后住院3~5 d;ESD组(n=17)病变直径2.0~6.5 cm,平均(4.2±2.2)cm;2处病变位于前壁,10处位于后壁,5处位于小弯侧;所有病变均为一次性切除;剥离时间26~157 min,平均(91.5±26.5)min;术中出血8例(47.1%),术中穿孔2例(11.8%),均给予金属夹夹闭并内科保守治疗取得成功,无迟发性出血和迟发性穿孔发生,术后住院3~6 d。结论应用注水型电刀行PESD是一种基于贲门解剖结构的创新术式,与常规ESD相比,可有效提高剥离速度,降低并发症发生率,使内镜手术更安全和快捷。

Isothermal reduction kinetics of zinc calcine under carbon monoxide

The reduction kinetics of zinc calcine under a CO atmosphere was evaluated by isothermal reductive roasting in a temperature range of 600-800℃.The extent of reaction of zinc calcine was measured using thermogravimetry(TG),and the decomposition mechanism of zinc ferrite in zinc calcine was analyzed based on variations in the soluble zinc and ferrous contents.The results indicate that the reaction was controlled by the nucleation of the products,with an apparent activation energy of 65.28 k J/mol.The partial pressure of CO affected the reaction rate more strongly than the CO intensity(defined as PCO/(PCO+PCO2)).The generation rate of zinc oxide was higher than that of ferrous oxide;therefore,the nucleation of ferrous oxide is the rate-determining step of the reaction.

Transcription and Secretion of Interleukin-1β and HMGB1 in Keratinocytes Exposed to Stimulations Mimicking Common Inflammatory Damages

Objective:Interleukin-1β(IL-1β)and high-mobility group box 1(HMGB1)are widely known damage-associated molecular patterns(DAMPs).However,their expression and secretion in different skin diseases,especially in inflammatory skin disorders,remain to be further elucidated.This study was performed to explore and compare the transcriptional and secretory levels of IL-1β and HMGB1 in keratinocytes under 3 types of stimulation:ultraviolet B(UVB)irradiation;co-stimulation by tumor necrosis factor-α(TNF-α)and interferon-γ(IFN-γ)(simulation of T helper 1 cell inflammatory challenge);and psoriasis-like stimulation by M5,a mixture of 5 proinflammatory cytokines.Methods:We used quantitative reverse-transcription polymerase chain reaction to determine the transcription levels of IL-1β and HMGB1.Western blotting and enzyme-linked immunosorbent assay were used to detect the secretion levels of IL-1β and HMGB1.The results were statistically analyzed by t test.Results:A rapid transcriptional and secretory response of IL-1β from keratinocytes occurred in all 3 types of stimulation mimicking common inflammatory environments(P<0.05).Transcription of HMGB1 was inhibited in all 3 types of stimulation(P<0.05),but secretion was increased after exposure to UVB irradiation and co-stimulation by TNF-α and IFN-γ(P<0.05).We observed no change in the secretion level of HMGB1 after treatment with M5(P=0.196).Conclusion:IL-1β is a critical cytokine for the immunomodulatory functions of keratinocytes in inflammatory responses.In this study,keratinocytes restrained transcription of HMGB1 when the secretion of HMGB1 was induced in certain stimulations(eg,by UVB exposure or stimulation by TNF-α and IFN-γ).

mTOR-Dependent Autophagy Machinery Is Inhibited in Fibroblasts of Keloid

Objectives:Mechanistic target of rapamycin(mTOR)activation has been identified in keloid.This study aimed to identify the role of mTOR-dependent autophagy activity in keloid.Methods:We detected the expression of specific proteins representing mTOR activity and baseline autophagy levels in keloid tissues(KTs)and primary keloid fibroblasts(KFs)using immunohistochemical staining and western blotting.Simultaneously,the formation of acid vesicles was assessed by acridine orange staining in KFs.To investigate whether mTOR-dependent pathway mediated the regulation of autophagy machinery in keloid,we first validated whether mTOR inhibitors,rapamycin(100 nmol/L)and KU-0063794(5mmol/L),could inhibit mTOR activity in KFs by western blotting.Then we explored the reverse effects on autophagy activity induced by mTOR inhibitors in the presence of lysosomal protease inhibitors by western blotting.Results:It demonstrated elevated expression of mTOR,S6,and their activated forms in KTs,and an elevated expression of p-S6 Ser235/236 in KFs,suggesting mTOR was activated in keloid.Less LC3 and Beclin1 were expressed in the cytoplasm of KFs,whereas Ubiquitin was abundantly expressed in KTs compared with extra-lesional tissues.In addition,at the cellular level,an impeded conversion of LC3-I to LC3-II was shown in KFs and the formation of acid vesicles were also decreased in KFs compared with normal fibroblasts(NFs),indicating that autophagy activity is defective in keloid.mTOR inhibitors,Rapamycin(E-64d+pepstatin vs.rapamycin+E-64d+pepstatin:[0.88±0.35]vs.[1.56±0.46],F=5.56,P=0.049)and KU-0063794(E-64d+pepstatin vs.KU-0063794+E-64d+pepstatin:[0.92±0.22]vs.[1.51±0.25],F=25.88,P=0.011)can reverse the inhibition effect on autophagy of KFs while inhibiting mTOR activity.Conclusion:Autophagy machinery is inhibited in keloid which is regulated by mTOR-dependent pathway.

Slow Down Dewetting in Polymer Films by Isocyanate-treated Graphite Oxide

Isocyanate-treated graphite oxides （iGOs） were well-dispersed into the polystyrene （PS） thin films and formed a novel network structure. With control in fabrication, an iGOs-web layer was horizontally embedded near the surface of the films and thus formed a composite slightly doped by iGOs. This work demonstrated that the iGOs network can remarkably depress the dewetting process in the polymer matrix of the composite, while dewetting often leads to rupture of polymer films and is considered as a major practical limit in using polymeric materials above their glass transition temperatures （Tg）. Via annealing the 50-120 nm thick composite and associated neat PS films at temperatures ranging from 35℃ to 70 ℃ above Tg, surface morphology evolution of the films was monitored by atomic force microscopy （AFM）. The iGOs-doped PS exhibited excellent thermal stability, i.e., the number of dewetting holes was greatly reduced and the long-term hole growth was fairly restricted. In contrast, the neat PS film showed serious surface fluctuation and a final rupture induced by ordinary dewetting. The method developed in this work may pave a road to reinforce thin polymer films and enhance their thermal stability, in order to meet requirements by technological advances.

Ultraviolet Induced Skin Inflammation

Ultraviolet(UV)induced skin inflammation(UISI)is associated with many skin disorders.However,the mechanism by which UV causes skin inflammation remains unclear.Studies evaluating UISIin vivo have mainly been conducted using mouse models.Current investigations indicate that the classic inflammatory pathways involving nuclear factor kappa B and Toll-like receptor contribute to the regulation of UISI.However,more novel signaling factors have been identified as being involved in this process,including interleukin 22 receptor-α,cluster of differentiation 28 and cluster of differentiation 1d,serum amyloid A1,estrogen,melatonin,peroxisome proliferator activated receptorsβ/δ,isocitrate dehydrogenase 2,and transglutaminase 2.In addition,the gene mutation offermitin family member 1 and selenium deficiency are reported to affect the phenotype of UISI.Although the actual roles of UISI in UV-related skin diseases need to be clarified,recent studies have reported the potent contribution of UISI to photocarcinogesis.To clarify the process and modulation of UISI,the special profiles of cytokines and inflammatory mediators and the core regulatory pathways should be identified clearly.These investigations would be promoted rapidly,accompanied by the conduction of high-quality clinical research on patients with UV-related skin disease and the construction of precise animal models of UISI.

Mediation of Anti-Keloid Effects of mTOR Inhibitors by Autophagy-Independent Machinery

Objective:Blocking mechanistic target of rapamycin(mTOR)activation with mTOR inhibitors has promising therapeutic potential for keloids.However,the precise mechanism of mTOR inhibitors remains unclear.This study was aimed to investigate the role of autophagy machinery in the anti-keloid effects of mTOR inhibitors.Methods:We first validated the biological effects induced by the mTOR inhibitors rapamycin(100 nmol/L)and KU-0063794(5μmol/L)on the proliferation,apoptosis,migration,and collagen synthesis of keloid fibroblasts(KFs)derived from Han Chinese persons through a Cell Counting Kit-8 assay,5-Bromo-2’-deoxyuridine incorporation,Annexin V/propidium iodide staining,migration,and western blotting.To explore whether autophagy machinery is involved in the anti-keloid effects of mTOR inhibitors,we first blocked the autophagy activation induced by rapamycin and KU-0063794 with a pharmacological autophagy inhibitor(wortmannin)or by silencing the key autophagy gene(ATG5),and we then re-evaluated these biological effects on KFs.Results:Blocking mTOR activation with either rapamycin or KU-0063794 completely inhibited proliferation,migration,and collagen synthesis of primary KFs but did not affect apoptosis.Incubating KFs with the autophagy inhibitor wortmannin or performingATG5 silencing abrogated the subsequent activation of autophagic activity induced by rapamycin(rapamycin+E-64d+pepstatinvs.rapamycin+wortmannin+E-64d+pepstatin:1.88±0.38vs.1.02±0.35,F=6.86,P=0.013),(non-sense control+rapamycinvs.ATG5 small interfering RNA+rapamycin:1.46±0.18vs.0.75±0.20,respectively;F=7.68,P=0.01)or KU-0063794(KU-0063794+E-64d+pepstatinvs.KU-0063794+wortmannin+E-64d+pepstatin:1.65±0.35vs.0.76±0.17,F=10.01,P=0.004),(NC+KU-0063794vs.ATG5 small interfering RNA+KU-0063794:1.59±0.50vs.0.77±0.09,F=5.93,P=0.02)as evidenced by decreased accumulation of LC3-II.However,blockage of autophagy induction in mTOR inhibitor-treated KFs with both methods did not disturb their anti-keloid effects,such as inhibition of cell viability,cell migration,and collagen synthesis(P>0.05 each).Conclusion:Blocking mTOR activation with the mTOR inhibitors rapamycin and KU-0063794 showed anti-keloid effects in KFs.Restoration of autophagy inhibition by mTOR inhibitors does not contribute to their anti-keloid effects.

An indirect approach for quantum-mechanical eigenproblems: duality transforms

We suggest an indirect approach for solving eigenproblems in quantum mechanics.Unlike the usual method,this method is not a technique for solving differential equations.There exists a duality among potentials in quantum mechanics.The first example is the Newton–Hooke duality revealed by Newton in Principia.Potentials that are dual to each other form a duality family consisting of infinite numbers of family members.If one potential in a duality family is solved,the solutions of all other potentials in the family can be obtained by duality transforms.Instead of directly solving the eigenequation of a given potential,we turn to solve one of its dual potentials which is easier to solve.The solution of the given potential can then be obtained from the solution of this dual potential by a duality transform.The approach is as follows:first to construct the duality family of the given potential,then to find a dual potential which is easier to solve in the family and solve it,and finally to obtain the solution of the given potential by the duality transform.In this paper,as examples,we solve exact solutions for general polynomial potentials.

GenOrigin: A comprehensive protein-coding gene origination database on the evolutionary timescale of life

The origination of new genes contributes to the biological diversity of life. New genes may quickly build their network, exert important functions, and generate novel phenotypes. Dating gene age and inferring the origination mechanisms of new genes, like primate-specific genes, is the basis for the functional study of the genes. However, no comprehensive resource of gene age estimates across species is available. Here,we systematically date the age of 9,102,113 protein-coding genes from 565 species in the Ensembl and Ensembl Genomes databases, including 82 bacteria, 57 protists, 134 fungi, 58 plants, 56 metazoa, and 178 vertebrates, using a protein-family-based pipeline with Wagner parsimony algorithm. We also collect gene age estimate data from other studies and uniformly distribute the gene age estimates to time ranges in a million years for comparison across studies. All the data are cataloged into Gen Origin(http://genorigin.chenzxlab.cn/), a user-friendly new database of gene age estimates, where users can browse gene age estimates by species, age, and gene ontology. In Gen Origin, the information such as gene age estimates,annotation, gene ontology, ortholog, and paralog, as well as detailed gene presence/absence views for gene age inference based on the species tree with evolutionary timescale, is provided to researchers for exploring gene functions.