Cell membrane vesicles derived from hBMSCs and hUVECs enhance bone regeneration

Bone tissue renewal can be enhanced through co-transplantation of bone mesenchymal stem cells(BMSCs)and vascular endothelial cells(ECs).However,there are apparent limitations in stem cell-based therapy which hinder its clinic translation.Hence,we investigated the potential of alternative stem cell substitutes for facilitating bone regeneration.In this study,we successfully prepared cell membrane vesicles(CMVs)from BMSCs and ECs.The results showed that BMSC-derived cell membrane vesicles(BMSC-CMVs)possessed membrane receptors involved in juxtacrine signaling and growth factors derived from their parental cells.EC-derived cell membrane vesicles(EC-CMVs)also contained BMP2 and VEGF derived from their parental cells.BMSC-CMVs enhanced tube formation and migration ability of hUVECs,while EC-CMVs promoted the osteogenic differentiation of hBMSCs in vitro.Using a rat skull defect model,we found that co-transplantation of BMSC-CMVs and EC-CMVs could stimulate angiogenesis and bone formation in vivo.Therefore,our research might provide an innovative and feasible approach for cell-free therapy in bone tissue regeneration.

Illuminating β-arrestin conformational dynamics by fluorine NMR

In a recent paper, solution-state ^(19)F NMR spectroscopy was used to probe the conformational dynamics of β-arrestin-1, an essential adaptor and signaling component of the G-protein couple receptor (GPCR) signaling pathway. This work reveals a highly complex conformational energy landscape of β-arrestin-1, and illuminates the molecular mechanism of the membrane phosphoinositide PIP2-induced β-arrestin-1 activation at residue level.(https://doi.org/10.1038/s41467-023-43694-1).

DNA binding mechanism of WhiB4 from Mycobacterium tuberculosis

Mycobacterium tuberculosis(Mtb),the pathogen of tuberculosis,has latently infected about one-third of the world's population and may lead to severe clinical symptoms and death.The WhiB4 protein,a transcription factor,plays a crucial role in the survival and pathology of Mtb.WhiB4 leads to the condensation of mycobacterial nucleoids and regulates the expression of genes involved in central metabolism,respiration,and maintaining redox homeostasis.Here,we report the solution structure of reduced apo-WhiB4 monomer,which consists of an unstructured N-terminal domain with four cysteine residues and a helix-turnhelix C-terminal domain that plays a major role in DNA binding.The C-terminal domain of WhiB4 binds DNA at the minor groove,with five positively charged lysine/arginine residues contacting DNA sugar-phosphate backbones through electrostatic interactions.AT-rich DNA sequences with narrower minor grooves are more preferred by WhiB4.The binding affinity of a single C-terminal domain of WhiB4 is weak.When oxidized,WhiB4 can form dimers and oligomers in different forms through disulfide bonds,which should significantly enhance its DNA binding ability through multivalent effect and change the local structure of target genes and influence their transcription.These structural features form the basis for WhiB4 to function as a redox-sensitive transcription factor in Mtb.

聚醚醚酮/碳化硅复合材料的结构及性能

为满足聚醚醚酮(PEEK)特种封装塑料在特殊环境中应用的高耐热性、高力学性能和透波性能等需求,通过分别将玻璃纤维(GF)和碳化硅纤维(SiC)经熔融共混的方式引入PEEK中,并采用注塑成型的方式制备PEEK复合材料;使用扫描电子显微镜、差示量热扫描仪、万能拉力试验仪、热重分析仪和矢量分析仪对复合材料的拉伸断裂面形貌结构、熔融和结晶行为、力学性能、热稳定性以及电磁屏蔽性能等特性进行了深入研究。结果表明,SiC纤维与PEEK基体具有良好的界面相容性,PEEK/SiC复合材料的力学性能较PEEK/GF复合材料更为优异,其拉伸断裂强度和模量及冲击强度分别可达130.4 MPa,7.39 GPa和14.8 kJ/m^(2),比纯PEEK分别提高了67%,347%和143%。此外,PEEK/SiC复合材料还表现出优异的热稳定性和良好的透波性能。研究结果说明,小尺寸SiC纤维填充PEEK复合材料具有更优的力学性能、耐热性能和透波性能。为在极端环境中应用的电子封装材料的研究与开发提供了有益的思路。

Analysis of differentially expressed genes in the sea cucumber Apostichopus japonicus under heat stress

The sea cucumber Apostichopus japonicus plays important roles in marine benthic ecosystem as environmental cleaners,and it is the important aquaculture species in China.High water temperature poses critical threat for the survival of A.japonicus,which has resulted in extensive death in summer.To explore the genes expression profiles under different levels of heat stress,the high-throughput RNA-seq was applied in this study.Our results revealed a total of 1371,1225 and 1408 differentially expressed genes(DEGs)in 26℃for 6 h,26℃for 48 h and 30℃for 6 h respectively in comparison with Control group.The pathway analysis suggested“Protein processing in endoplasmic reticulum(ER)”was significantly enriched in all these heat stress(HS)treatment groups.The expression results of key DEGs in this pathway(Hsp70,Derlin,NEF,PDI,GPR94 and ERP57)by qRT-PCR was in accordance with the RNA-seq data.The subcluster analysis of DEGs revealed that a variety of heat shock proteins(HSPs)and calcium ion binding proteins had an obvious up-regulated expression in 26℃for 6 h,comparatively low expression in 26℃for 48 h,and the highest expression in 30℃for 6 h.The other DEGs subcluster,consisting of critical components of extracellular matrix(ECM)and a subset of peptidases and proteases,showed significantly rising tendency in 30℃for 6 h.Additionally,the expression of matrix metalloproteases(MMP1,MMP16 and MMP19)was prominently affected by HS,and peaked in 30℃for 6 h.This study provides a series of candidate genes for further study about heat shock response in A.japonicus,especially genes associated with protein processing in ER and regulation of ECM,which also offers new insights into cellular homeostasis under stressful conditions in marine invertebrates.

Bedside ultrasound-guided water injection assists endoscopically treatment in esophageal perforation caused by foreign bodies: A case report

BACKGROUND Fishbone migration from the esophagus to the neck is relatively uncommon in clinical practice.Several complications secondary to esophageal perforation after ingestion of a fishbone have been described in the literature.Typically,a fishbone is detected and diagnosed by imaging examination and is usually removed by a neck incision.CASE SUMMARY Herein,we report a case of a 76-year-old patient with a fishbone in the neck that had migrated from the esophagus and that was in close proximity to the common carotid artery,and the patient experienced dysphagia.An endoscopically-guided neck incision was made over the insertion point in the esophagus,but the surgery failed due to having a blurred image at the insertion site during the operation.After injection of normal saline laterally to the fishbone in the neck under ultrasound guidance,the purulent fluid outflowed to the piriform recess along the sinus tract.With endoscopic guidance,the position of the fish bone was precisely located along the direction of liquid outflow,the sinus tract was separated,and the fish bone was removed.To the best of our knowledge,this is the first case report describing bedside ultrasound-guided water injection positioning combined with endoscopy in the treatment of a cervical esophageal perforation with an abscess.CONCLUSION In conclusion,the fishbone could be located by the water injection method under the guidance of ultrasound and could be accurately located along the outflow direction of the purulent fluid of the sinus by the endoscope and was removed by incising the sinus.This method can be a nonoperative treatment option for foreign body-induced esophageal perforation.

UWB Positioning System Based on Genetic Algorithm

In order to enhance the positioning accuracy, a UWB positioning system based on genetic algorithm is proposed. Firstly, it uses the DW1000 module to measure the distance, and preprocesses the measured data to remove noise. Then, a positioning equation is established according to the processed distance information, and the genetic algorithm is used to solve the equation to obtain the coordinates of the unknown node. The experimental results show that the measured positioning accuracy is within 30 cm, which means that the system can obtain a good positioning effect and meet the need for precise positioning.

Hybrid Location Algorithm Based on Cuckoo and Statistical Manifold

To improve the location accuracy, a hybrid location algorithm based on cuckoo and statistical manifold method is proposed. It combines the cuckoo algorithm's strong global optimization ability and the statistical manifold’s accurate positioning ability fully. The simulation results show that the hybrid location algorithm has higher accuracy and reduces the influence of initial value selection on location accuracy.

Identification of a functional 339 bp Alu insertion polymorphism in the schizophrenia-associated locus at 10q24.32

Genome-wide association studies(GWAS)have identified multiple single nucleotide polymorphisms(SNPs)or small indels robustly associated with schizophrenia;however,the functional risk variations remain largely unknown.We investigated the 10q24.32 locus and discovered a 339 bp Alu insertion polymorphism(rs71389983)in complete linkage disequilibrium(LD)with the schizophrenia GWAS risk variant rs7914558.The presence of the Alu insertion at rs71389983 strongly repressed transcriptional activities in in vitro luciferase assays.This polymorphism may be a target for future mechanistic research.Our study also underlines the importance and necessity of considering previously underestimated Alu polymorphisms in future genetic studies of schizophrenia.

A Novel Statistical Manifold Algorithm for Position Estimation

In this paper, a novel statistical manifold algorithm is proposed for position estimation of sensor nodes in a wireless network, making full use of distance information available among unknown nodes and simultaneous localization of multiple unknown nodes. To begin, a ranging model including the distance information among unknown nodes is established. With the reparameterization of the natural parameter and natural statistic,the solution problem of the ranging model is transformed into a parameter estimation problem of the curved exponential family.Then, a natural gradient method is adopted to deal with the parameter estimation problem of the curved exponential family.To ensure the convergence of the proposed algorithm, a particle swarm optimization method is utilized to obtain initial values of the unknown nodes. Experimental results indicate that the proposed algorithm can improve the positioning accuracy, compared with the traditional algorithm.

Optimal Design of Electrical Machines Assisted by Hybrid Surrogate Model Based Algorithm

In this paper,for design of large-scale electromagnetic problems,a novel robust global optimization algorithm based on surrogate models is presented.The proposed algorithm can automatically select a proper meta-model technique among multiple alternatives.In this paper,three representative meta-modeling techniques including ordinary Kriging,universal Kriging,and response surface method with multi-quadratic radial basis functions are applied.In each optimization iteration,the above three models are used for parallel calculation.The proposed hybrid surrogate model optimization algorithm synthesizes advantages of these different meta-models.Without verification of a specific meta-model,a suitable one for the engineering problem to be analyzed is automatically selected.Therefore,the proposed algorithm intends to make a better trade-off between numerical efficiency and searching accuracy for solving engineering problems,which are characterized by stronger non-linearity,higher complexity,non-convex feasible region,and expensive performance analysis.

Joint Optimization of Communications and Computing Resources Allocation for Deterministic Transmission in Wireless Edge Networks

Motivated by 5th generation wireless systems(5G),a large number of emerging applications appear,which put forward higher requirements for the task’s transmission determinacy,which refers to the delay and jitter.To satisfy the deterministic requirement,mobile edge computing(MEC)is envisioned as a promising technique for reducing the end-to-end delay significantly.In this paper,we consider delaysensitive task and jitter-sensitive task,and then formulate the joint communications and computing optimization problem under the latency,the total bandwidth,the total transmission power of base station(BS)and the computing ability of the MEC server constraints to minimize the delay and jitter in a multiuser MEC system.Because of the problems are nonconvex,we decouple them into some subproblems and propose the corresponding algorithms to obtain a suboptimal solution.Finally,numerical results show that the proposed algorithms have a significant performance gain over the traditional solution in terms of the delay and the jitter.

Retroperitoneal parasitic fetus: A case report

BACKGROUND Fetus-in-fetu(FIF)is an extremely rare congenital abnormal mass,in which a normal fetus’s vertebral axis frequently connected with malformed fetus around this axis.Here,we report the case of a male infant aged 26 d presenting with retroperitoneal parasitic fetus.CASE SUMMARY In a prenatal examination,we first detected an abdominal mass measuring 7.8 cm×5.1 cm×6.8 cm in a mother’s abdomen at 25 gestational weeks and teratoma was suspected.After the fetal was born,we did a magnetic resonance imaging(MRI)and ultrasonography on him and saw a distinctive limb with five-toes.According to the result of MRI,ultrasonography and postoperative pathology,he finally was diagnosed with FIF.CONCLUSION A laparotomy was performed at 26 d of age with excision of the retroperitoneal cystic tumor,which measured about 10 cm in diameter.According to the result of imaging and histological test,FIF was confirmed.

气候变化与海洋微塑料污染的相互影响研究进展

气候变化和海洋微塑料污染已成为全球关注的热点问题,两者在相当长的一段时间内会同时存在.然而,基于文献报道的实验结果和环境监测数据,关于气候变化和海洋微塑料污染的研究大多是相互独立的,缺乏对两者相互影响的清晰认知.本文通过综述全球气候变化状况和海洋微塑料的污染现状,总结了气候变化下海洋生态环境的改变,特别是海水升温、酸化、低氧等与海洋微塑料污染之间的相互影响,发现气候变化会加剧海洋微塑料污染,改变微塑料的海洋环境行为,同时海洋微塑料污染也会影响气候变化,加剧气候变暖、海洋酸化和低氧,所以两者是密切相关的.本文还展望了未来的研究方向和前景,以期为有效应对全球气候变化和海洋微塑料污染提供重要的理论基础.

Intensive phototherapy vs.exchange transfusion for the treatment of neonatal hyperbilirubinemia:a multicenter retrospective cohort study

Background:Intensive phototherapy(IPT)and exchange transfusion(ET)are the main treatments for extreme hyperbilirubinemia.However,there is no reliable evidence on determining the thresholds for these treatments.This multicenter study compared the effectiveness and complications of IPT and ET in the treatment of extreme hyperbilirubinemia.Methods:This retrospective cohort study was conducted in seven centers from January 2015 to January 2018.Patients with extreme hyperbilirubinemia that met the criteria of ET were included.Patients were divided into three subgroups(low-,medium-,and high-risk)according to gestational week and risk factors.Propensity score matching(PSM)was performed to balance the data before treatment.Study outcomes included the development of bilirubin encephalopathy,duration of hospitalization,expenses,and complications.Mortality,auditory complications,seizures,enamel dysplasia,ocular motility disorders,athetosis,motor,and language development were evaluated during follow-up at age of 3 years.Results:A total of 1164 patients were included in this study.After PSM,296 patients in the IPT only group and 296 patients in the IPT plus ET group were further divided into the low-,medium-,and high-risk subgroups with 188,364,and 40 matched patients,respectively.No significant differences were found between the IPT only and IPT plus ET groups in terms of morbidity,complications,and sequelae.Hospitalization duration and expenses were lower in the low-and medium-risk subgroups in the IPT only group.Conclusions:In this study,our results suggest that IPT is a safe and effective treatment for extreme hyperbilirubinemia.The indication of ET for patients with hyperbilirubinemia could be stricter.However,it is necessary to have a contingency plan for emergency ET as soon as IPT is commenced especially for infants with risk factors.If IPT can be guaranteed and proved to be therapeutic,ET should be avoided as much as possible.

Biodegradation of waste refrigerator polyurethane by mealworms

Refrigerator insulation replacement results in discarding a large amount of waste refrigerator polyurethane(WRPU).Insect larvae like mealworms have been used to biodegrade pristine plastics.However,knowledge about mealworms degrading WRPU is scarce.This study presents an in-depth investigation of the degradation of WRPU by mealworms using the micro-morphology,composition,and functional groups of WRPU and the egested frass characteristics.It was found that the WRPU debris in frass was scoured,implying that WRPU was ingested and degraded by mealworms.The carbon content of WRPU-based frass was lower than that of WRPU,indicating that mealworms utilized WRPU as a carbon source.The urethane groups in WRPU were broken,and benzene rings’C=C and C–H bonds in the isocyanate disappeared after being ingested by mealworms.Thermal gravimetric-differential thermal gravimetry analysis showed that the weight loss temperature of WRPU-based frass was 300°C lower than that of WRPU,indicating that the thermal stability of WRPU deteriorated after being ingested.The carbon balance analysis confirmed that carbon in the ingested WRPU released as CO_(2) increased from 18.84%to 29.80%,suggesting that WRPU was partially mineralized.The carbon in the mealworm biomass ingesting WRPU decreased.The possible reason is that WRPU does not supply sufficient nutrients for mealworm growth,and the impurities and odor present in WRPU affect the appetite of the mealworms.The microbial community analysis indicated that WRPU exerts a considerable effect on the gut microorganism of mealworms.These findings confirm that mealworms degrade WRPU.

SIMROID机器人在口腔医学生麻醉教学中的应用

目的:本研究利用SIMROID机器人将接诊流程模式化应用于本科生教学培训考核,并通过问卷调查的方式对其进行评价。方法:以6岁患儿局部浸润麻醉下拔除下颌滞留的乳中切牙为蓝本,编撰人机交互的医患沟通和行为管理脚本,将机器人的应答和相应头部、手部的动作导入SIMROID机器人。在课堂借助PPT讲解儿童口腔科的医患沟通和行为管理后,将82名口腔医学大学四年级医学生随机分成机器人组(实验组)和同伴练习组(对照组),之后两组互换。实习结束后,学生填写调查问卷,对两种教学模式进行评价。结果:学生认为机器人的外形与真人还是有一定差距(P<0.001),而在模拟临床突发情况时机器人表现更好(P=0.001);使用同伴沟通更能考虑到患者的疼痛感受(P=0.001)。结论:本研究利用SIMROID机器人完成儿童口腔局部浸润麻醉时“标准病人”的建立,尝试情景化临床思维训练和医患沟通、行为管理教学的新途径,为进一步开展和推广机器人模拟临床教学奠定了基础。

新生儿消化道穿孔患儿的临床特点及治疗结局

目的探讨新生儿消化道穿孔患儿的病因、临床特点、治疗和结局。方法选取2020年1月至2022年4月四川大学华西第二医院新生儿科收治的63例新生儿消化道穿孔患儿为研究对象。采取回顾性分析方法,根据消化道穿孔部位,将其分为肠穿孔组(n=51)、胃穿孔组(n=8)和穿孔部位不明组(n=4)。回顾性分析所有患儿的一般临床资料、实验室及影像学检查结果、手术相关情况、术后治疗及预后等。本研究遵循的程序符合四川大学华西第二医院伦理委员会规定,通过该伦理委员会批准(审批文号:医学科研2022伦审批第〔141〕号)。结果①消化道穿孔原因:胃穿孔组患儿均因先天性胃壁肌层缺损所致(8/8);肠穿孔组患儿中,由于NEC、自发性肠穿孔(SIP)、肠闭锁、食管闭锁合并食管气管瘘、胎粪性腹膜炎与先天性巨结肠所致穿孔各为38例(74.5%)、7例(13.7%)、3例(5.9%)、1例(2.0%)、1例(2.0%)与1例(2.0%);其余4例穿孔部位不明。②临床表现:患儿均以腹胀、气促、呼吸困难、反应差等为主要表现。③辅助检查:其中53例(81.0%,51/63)患儿的腹部X射线摄片检查结果提示腹腔游离气体。④治疗措施:60例(95.2%)接受手术治疗(剖腹探查术为38例,仅行腹腔引流术为12例,腹腔引流术+剖腹探查术为10例),3例采取保守治疗措施。⑤治疗结局:40例(63.5%)治愈出院,17例(27.0%)主动要求出院,6例(9.5%)住院死亡。45例(75.0%,45/60)接受手术患儿术后恢复肠内营养。结论NEC、SIP、先天性胃壁肌层缺损是导致新生儿消化道穿孔的主要病因。结合临床表现及影像学检查结果尽早识别、积极外科手术,或可降低新生儿消化道穿孔患儿死亡率。

Distinguishing transgenic from non-transgenic Arabidopsis plants by ~1H NMR-based metabolic fingerprinting

We have recently reported the construction of an nuclear magnetic resonance （NMR）-based metabonomics study platform, Automics. To examine the application of Automics in transgenic plants, we performed metabolic fingerprinting analysis, i.e., 1H NMR spectroscopy and multivariate analysis, on wild-type and transgenic Arabidopsis. We found that it was possible to distinguish wild-type from four transgenic plants by PLS-DA following application of orthogonal signal correction （OSC）. Scores plot following OSC clearly demonstrates significant variation between the transgenic and non-transgenic groups, suggesting that the metabolic changes among wild-type and transgenic lines are possibly associated with transgenic event, We also found that the major contributing metabolites were some specific amino acids （i.e., threonine and alanine）, which could correspond to the insertion of the selective marker BAR gene in the transgenic plants. Our data suggests that NMR-based metabonomics is an efficient method to distinguish fingerprinting difference between wild-type and transgenic plants, and can potentially be applied in the bio-safety assessment of transgenic plants.

Metamorphism and Zircon Geochronological Studies of Metagabbro Vein in the Yushugou Granulite-Peridotite Complex from South Tianshan,China

Yushugou granulite-peridotite complex,located at the east part of the northern margin of South Tianshan,may represent an ophiolitic slice subducted to 40–50 km depth with high-pressure granulite facies metamorphism.Although a lot of studies have been conducted on rocks in this belt,the rock association and tectonic background of the ophiolitic slice are still in dispute.A detailed study on petrology,phase equilibrium modeling and U-Pb zircon ages have been performed on the metagabbro vein in peridotite unit to constrain the tectonic evolution of the Yushugou granulite-peridotite complex.Three stages of mineral assemblage in the metagabbro were defined as stage I:Cpx^A+Opx^A+Pl^A,which represents the original minerals of the metagabbro vein;stage II:Cpx^B+Opx^B+Pl^B+Spl,which represents the mineral assemblage of granulite facies metamorphism with peak P-T conditions of 4.2–6.9 kbar and 940–1070℃;stage III is characterized by the existence of prehnite,thomsonite and amphibole in the matrix,indicating that the metagabbro vein may be influenced by fluids during retrograde metamorphism.Combined with the crosscut relationship,it can be deduced that the metagabbro vein,together with the peridotite in Yushugou granulite-peridotite complex has experienced similar high-temperature granulite facies metamorphism.The zircon chronological data shows that the protolith age of the metagabbro vein is 400.5±6.2 Ma,reflecting Devonian magmatism event and the granulite facies metamorphism occurred at^270 Ma which may be related to the post-collisional magmatism.