Investigation on the differences of four flavonoids with similar structure binding to human serum albumin

Flavonoids are structurally diverse and the most ubiquitous groups of polyphenols distributed in the various plants,which possess intensive biological activities.In this study,the interaction mechanisms between four flavonoids containing one glucose unit with similar molecular weight isolated from the Tibetan medicinal herb Pyrethrum tatsienense,namely.apigenin-7-O-β-D-glucoside（1）,luteolin-7-O-β-D-glucoside（2）.quercetin-7-O-β-D-glucoside（3）.quercetin-3-O-β-D-glycoside（4）.and human serum albumin（HSA）,were investigated by fluorescence.UV-vis absorbance,circular dichroism,and molecular modeling.The effects of biological metal ions Mg2＋,Zn2＋,and Cu2＋ on the binding affinity between flavonoids and HSA were further examined.Structure-activity relationships of four flavonoids binding to HSA were discussed in depth and some meaningful conclusions have been drawn by the experiment data and theoretical simulation.In addition,an interesting phenomenon was observed that the microenvironment of the binding site I in HSA has hardly changed in the presence of 4 differentiating from the other three flavonoids on the basis of conformation investigations.

Rules Mining-Based Gene Expression Programming for the Multi-Skill Resource Constrained Project Scheduling Problem

Themulti-skill resource-constrained project scheduling problem(MS-RCPSP)is a significantmanagement science problem that extends from the resource-constrained project scheduling problem(RCPSP)and is integrated with a real project and production environment.To solve MS-RCPSP,it is an efficient method to use dispatching rules combined with a parallel scheduling mechanism to generate a scheduling scheme.This paper proposes an improved gene expression programming(IGEP)approach to explore newly dispatching rules that can broadly solve MS-RCPSP.A new backward traversal decoding mechanism,and several neighborhood operators are applied in IGEP.The backward traversal decoding mechanism dramatically reduces the space complexity in the decoding process,and improves the algorithm’s performance.Several neighborhood operators improve the exploration of the potential search space.The experiment takes the intelligent multi-objective project scheduling environment(iMOPSE)benchmark dataset as the training set and testing set of IGEP.Ten newly dispatching rules are discovered and extracted by IGEP,and eight out of ten are superior to other typical dispatching rules.

Association of daily sitting time and leisure-time physical activity with body fat among U.S.adults

Background:Prolonged sitting and reduced physical activity lead to low energy expenditures.However,little is known about the joint impact of daily sitting time and physical activity on body fat distribution.We investigated the independent and joint associations of daily sitting time and physical activity with body fat among adults.Methods:This was a cross-sectional analysis of U.S.nationally representative data from the National Health and Nutrition Examination Survey2011-2018 among adults aged 20 years or older.Daily sitting time and leisure-time physical activity(LTPA)were self-reported using the Global Physical Activity Questionnaire.Body fat(total and trunk fat percentage)was determined via dual X-ray absorptiometry.Results:Among 10,808 adults,about 54.6%spent 6 h/day or more sitting;more than one-half reported no LTPA(inactive)or less than 150 min/week LTPA(insufficiently active)with only 43.3%reported 150 min/week or more LTPA(active)in the past week.After fully adjusting for sociodemographic data,lifestyle behaviors,and chronic conditions,prolonged sitting time and low levels of LTPA were associated with higher total and trunk fat percentages in both sexes.When stratifying by LTPA,the association between daily sitting time and body fat appeared to be stronger in those who were inactive/insuufficiently active.In the joint analyses,inactive/insuufficiently active adults who reported sitting more than 8 h/day had the highest total(female:3.99%(95%confidence interval(95%CI):3.09%-4.88%);male:3.79%(95%CI:2.75%-4.82%))and trunk body fat percentages(female:4.21%(95%CI:3.09%-5.32%);male:4.07%(95%CI:2.95%-5.19%))when compared with those who were active and sitting less than 4 h/day.Conclusion:Prolonged daily sitting time was associated with increased body fat among U.S.adults.The higher body fat associated with 6 h/day sitting may not be offset by achieving recommended levels of physical activity.

A 48-bp deletion upstream of LIGULELESS 1 alters rice panicle architecture

Panicle architecture is an agronomic determinant of crop yield and a target for cereal crop improvement.To investigate its molecular mechanisms in rice,we performed map-based cloning and characterization of OPEN PANICLE 1(OP1),a gain-of-function allele of LIGULELESS 1(LG1),controlling the spread-panicle phenotype.This allele results from a 48-bp deletion in the LG1 upstream region and promotes pulvinus development at the base of the primary branch.Increased OP1 expression and altered panicle phenotype in chimeric transgenic plants and upstream-region knockout mutants indicated that the deletion regulates spread-panicle architecture in the mutant spread panicle 1(sp1).Knocking out BRASSINOSTEROID UPREGULATED1(BU1)gene in the background of OP1 complementary plants resulted in compact panicles,suggesting OP1 may regulate inflorescence architecture via the brassinosteroid signaling pathway.We regard that manipulating the upstream regulatory region of OP1 or genes involved in BR signal pathway could be an efficient way to improve rice inflorescence architecture.

A multi-point collaborative DDoS defense mechanism for IIoT environment

Nowadays,a large number of intelligent devices involved in the Industrial Internet of Things(IIoT)environment are posing unprecedented cybersecurity challenges.Due to the limited budget for security protection,the IIoT devices are vulnerable and easily compromised to launch Distributed Denial-of-Service(DDoS)attacks,resulting in disastrous results.Unfortunately,considering the particularity of the IIoT environment,most of the defense solutions in traditional networks cannot be directly applied to IIoT with acceptable security performance.Therefore,in this work,we propose a multi-point collaborative defense mechanism against DDoS attacks for IIoT.Specifically,for the single point DDoS defense,we design an edge-centric mechanism termed EdgeDefense for the detection,identification,classification,and mitigation of DDoS attacks and the generation of defense information.For the practical multi-point scenario,we propose a collaborative defense model against DDoS attacks to securely share the defense information across the network through the blockchain.Besides,a fast defense information sharing mechanism is designed to reduce the delay of defense information sharing and provide a responsive cybersecurity guarantee.The simulation results indicate that the identification and classification performance of the two machine learning models designed for EdgeDefense are better than those of the state-of-the-art baseline models,and therefore EdgeDefense can defend against DDoS attacks effectively.The results also verify that the proposed fast sharing mechanism can reduce the propagation delay of the defense information blocks effectively,thereby improving the responsiveness of the multi-point collaborative DDoS defense.

融合纳米囊泡在癌症治疗中的研究进展

细胞外囊泡(Extracellular vesicles,EVs)凭借其天然的生物学特性和后天获得的多功能优势,逐渐参与到机体调节的生理及病理过程中,成为疾病预防、治疗、评估的有力工具。癌症是目前危害人类健康的重大疾病之一,其临床治疗手段主要依靠放化疗、手术切除及新兴的免疫治疗。然而,以上治疗方式存在药物毒副作用强、生物利用度低、治疗成本昂贵、易复发等不足,极大影响癌症的治疗进展。因此,EVs的出现为癌症治疗提供了更加安全、高效的治疗策略,但天然产生的单一EVs产量低、自体靶向能力弱且载药能力低,在疾病治疗临床转化方面的发展受限。因此,建立普适性强且灵活性好的多功能融合纳米囊泡是扩大EVs实际效用的关键。本综述系统地总结了融合纳米囊泡的制备方法、分类特点、在癌症治疗中的应用及面临的挑战,为开发有前途的精准医疗纳米平台提供理论指导。

Transcriptomic and proteomic studies of condylar ossification of the temporomandibular joint in porcine embryos

Background:The ossification mechanism of the temporomandibular joint(TMJ)condyle remains unclear in human embryo.The size and structure of TMJ,shape of articular disc and the characteristics of omnivorous chewing in the pig are similar to those of humans.The pig is an ideal animal for studying the mechanism of ossification of the TMJ condyle during the embryonic period.Method:In a previous study by our group,it was found that there was no condylar ossification on embryonic day(E)45,but the ossification of condyle occurred between E75 and E90.In this study,a total of 12 miniature pig embryos on E45 and E85 were used.Six embryos were used for tissue sections(3 in each group).The remaining six embryos were used for transcriptomic and proteomic studies to find differential genes and proteins.The differentially expressed genes in transcriptome and proteomic analysis were verified by QPCR.Results:In total,1592 differential genes comprising 1086 up-regulated genes and 506 down-regulated genes were screened for fold changes of≥2 to≤0.5 between E45 and E85.In the total of 4613 proteins detected by proteomic analysis,there were 419 differential proteins including 313 up-regulated proteins and 106 down-regulated proteins screened for fold changes of≥2 to≤0.5 between E45 and E85.A total of 36 differential genes differing in both transcriptome and proteome analysis were found.QPCR analysis showed that 14 of 15 selected genes were consistent with transcriptome analysis.Conclusion:Condylar transcriptome and proteomic analysis during the development of TMJ in miniature pigs revealed the regulatory genes/proteins of condylar ossification.

Automated apoptosis identification in fluorescence imaging of nucleus based on histogram of oriented gradients of high-frequency wavelet coefficients

The automatic and accurate identification of apoptosis facilitates large-scale cell analysis.Most identification approaches using nucleus fluorescence imaging are based on specific morphological parameters.However,these parameters cannot completely describe nuclear morphology,thus limiting the identification accuracy of models.This paper proposes a new feature extraction method to improve the performance of the model for apoptosis identification.The proposed method uses a histogram of oriented gradient(HOG)of high-frequency wavelet coefficients to extract internal and edge texture information.The HOG vectors are classified using support vector machine.The experimental results demonstrate that the proposed feature extraction method well performs apoptosis identification,attaining 95:7% accuracy with low cost in terms of time.We confirmed that our method has potential applications to cell biology research.

Polyvinyl alcohol–potassium iodide gel probe to monitor the distribution of reactive species generation around atmospheric-pressure plasma jet

This study proposes polyvinyl alcohol–potassium iodide(PVA–KI)as a novel gel chemical probe.The probe uses the reactions among PVA,KI,water,borax,and oxidative species to visualize the distribution of reactive species.This method provides information regarding the distribution of reactive species by coloration on the gel surface.The effects of the surrounding gas phase on the distribution and diffusion of the reactive species are also investigated using the PVA–KI gel probe.Further,the relationship between the irradiation distance and reactive species diffusion is determined on the surface of the PVA–KI probe with and without plastic shielding.Adjusting the irradiation distance appropriately leads to an increase in the modified area as detected by the PVA–KI gel probe analysis.The relative concentration distributions of the reactive species are also obtained from visualized color distributions measured using a colorimeter.Furthermore,reactive species generation by long-scale line plasma is confirmed by the color reaction on the PVA–KI gel surface,with a greater area being covered by an atmospheric-pressure pulsed microwave line plasma source.

水的溶剂效应对植物防晒剂UV-B吸收的影响

抵御UV-B(280~320nm)对地球生命至关重要.研究UV-B防晒分子周边的环境对UV-B吸收的影响有助于了解防晒剂的光吸收机制.水作为溶剂在细胞中无处不在,但是其对防晒剂吸收UV-B的影响还未被充分研究.本文基于第一性原理,重点研究了芥子酸酯及其相关植物防晒分子的UV-B吸收中水的溶剂作用.芥子酸酯阴离子对UV-B的吸收作用来自与其周边水溶剂环境的相互作用,因此其也是在实际环境中起到防晒功能的防晒物种。在第一性原理模拟中,隐式水溶剂模型可以提供溶剂化的介电环境,显式水溶剂模型可以与芥子酸酯阴离子形成氢键,这些因素都可以显著改变与芥子酸酯阴离子吸收UV-B相关的跃迁轨道性质.同时,发现了植物防晒剂的分子偶极矩可以作为衡量其UV-B吸收能力对周围极性环境敏感程度的指标.本工作为开发新型水溶性UV-B防晒剂提供了起点.

Carotid-subclavian bypass and endovascular aortic repair of Kommerell’s diverticulum with aberrant left subclavian artery:A case report

BACKGROUND Kommerell’s diverticulum(KD)with aberrant left subclavian artery is a rare congenital deformity and also has very little research literature about it(35%of case study).There are three types of aortic arch diverticulum.Even literature concerning the treatment options are limited.CASE SUMMARY We present a case report of a 50-year-old male with KD in the right aortic arch with aberrant left subclavian artery.We conducted a total endovascular repair procedure,which is innovative and will spread more light in the medical world.Our patient has no past medical history and is a non-smoker and non-alcoholic.Patient presented with shortness of breath,chest pain and dizziness for six months.Blood tests were done and computerized tomography(CT)angiogram of the chest confirmed the diagnosis,illustrating showed a 3.9 cm KD.On Day 1,the CT angiogram showed mild dilatation of the thoracic aorta,adjacent esophagus,trachea was compressed and displaced.Surgery was planned as the treatment modality.Carotid-Subclavian artery bypass and endovascular aortic repair was conducted.We used prolene 5-0 C1 sutures to precisely anastomose a 6-mm Dacron graft to the left subclavian artery.Haemostasis was secured and wounds were closed.Protamine was administered and patient was shifted to intensive care unit.Post-operative,patient responded favorably and was discharged.Regular follow-up is done.CONCLUSION The procedure we performed is novel.This will help the cardio-thoracic surgeons a better insight about the full procedures we conducted,thereby bringing more light and better treatment options in managing KD with aberrant subclavian artery.

交联改性对静电纺乌拉草提取液/聚乙烯醇纳米纤维膜性能的影响

为了优化用于医用敷料的乌拉草提取液/聚乙烯醇纳米纤维膜的耐水性,对制备好的纤维膜进行气相交联改性。选用戊二醛和浓盐酸作为交联剂和催化剂,在满足医用敷料性能的基础上提高膜的耐水性,进而提高抗菌性,并研究交联时间对膜的影响,确定最优交联时间。采用扫描电子显微镜、电子单纤强力仪及红外光谱仪对改性前后膜的微观形貌、力学性能及分子结构进行表征,并对膜的透气性和孔隙率、接触角和吸水性以及抗菌性进行测试。结果表明,经戊二醛交联改性后,纳米纤维膜的接触角从16°逐渐增大到78°,耐水性显著提高;其形貌、水蒸气透过率及孔隙率均能满足医用敷料的要求。随着交联时间的延长,其力学性能和吸水倍率先增强后减弱,在交联4 h时分别达到最大值(7.34±0.80)MPa和857%;其抗菌性在交联2 h时达到最优,此时大肠杆菌和金黄色葡萄球菌的抑菌圈直径分别为3.0 mm和1.1 mm。由以上结论得出,交联2 h和4 h的纳米纤维膜的综合性能最好。

急性髓细胞白血病患者CD96和CD123的表达及对预后的意义

目的检测CD96、CD123在急性髓细胞白血病(AML)患者中的表达,探讨其与AML疗效和预后的关系。方法选取156例AML患者为观察对象,选取同期该院健康体检者150例作为对照组。采用流式细胞术检测CD96、CD123表达情况,并分析CD96、CD123表达与化疗疗效的关系。结果 AML患者CD96、CD123的阳性表达率与对照组比较,差异有统计学意义(P <0.05);AML患者中CD96、CD123阳性表达的缓解率均低于阴性表达者(P <0.05);AML患者中CD96、CD123阳性表达的生存率均低于阴性表达者(P <0.05);AML患者中CD96、CD123阳性表达的化疗后感染、化疗后复发发生率均高于阴性表达者(P <0.05);AML患者中CD96、CD123阳性表达的中位生存期均低于阴性表达者(P<0.05)。结论 CD96、CD123在AML中均有不同程度的表达,其阳性表达可能与原发耐药或复发进展有关,可作为判断AML患者预后的相关指标。

输尿管导管辅助软镜工作内鞘扩张输尿管在二期软镜碎石术中置鞘困难时的应用

目的探讨输尿管导管辅助软镜工作内鞘扩张输尿管在二期输尿管软镜碎石术中置鞘困难时的临床应用。方法对一期放置5F输尿管支架管、二期行输尿管软镜碎石术时置鞘困难的9例患者,采用5F输尿管导管辅助12F软镜工作内鞘扩张输尿管后置鞘并行输尿管软镜钬激光碎石术。结果经扩张后的9例患者,软镜工作鞘均置于满意位置并成功碎石,未出现严重并发症。术后随访6个月未发现输尿管狭窄。结论应用输尿管导管辅助软镜工作内鞘扩张输尿管对二期行输尿管软镜碎石术置鞘困难的患者有提高手术成功率、降低手术风险、减轻经济负担的作用,是二期行输尿管软镜碎石术出现置鞘困难时有效、便捷、安全的辅助手段。

间充质干细胞来源的胞外囊泡在急性肝衰竭治疗中的研究进展

急性肝衰竭(Acute liver failure,ALF)是指无肝脏基础疾病而在短时间内发生大量肝细胞坏死及严重肝功能损害,并引起多器官障碍的危重临床综合征。ALF的病死率较高,但临床上还没有特效的治疗方法。因此,开发新的治疗手段来有效缓解肝衰竭的进展是研究者普遍关注且亟需解决的关键问题。目前临床前研究的方法中,干细胞疗法被认为是治疗肝衰竭最有潜力的方法。但干细胞固有的临床风险阻滞了它的进一步应用,加上越来越多的证据表明,干细胞的生物学功能在很大程度上归功于其分泌的胞外囊泡(Extracellular vesicles,EVs)。EVs作为细胞自然产生的纳米级囊泡,已经成为ALF治疗中最具吸引力的纳米治疗手段之一。本文主要综述了EVs的形成、组分与分离,以及EVs在ALF治疗中的潜在机制。

不同经上皮角膜胶原交联方法治疗进展期圆锥角膜的早期疗效观察

目的:观察比较不同经上皮角膜胶原交联方法(transepithelial corneal collagen cross-linking,TE-CXL)治疗进展期圆锥角膜的早期疗效。方法:回顾性研究。将24例34眼进展期圆锥角膜分为三组,低渗CXL组10眼接受低渗胶原交联治疗,I-CXL5min组14眼接受离子导入5min胶原交联治疗,I-CXL10min组10眼接受离子导入10min胶原交联治疗。治疗前,治疗后1wk,1、3、6mo观察视力、Pentacam眼前节分析仪、角膜激光共焦显微镜、光学相关断层扫描结果变化。结果:术后6mo,I-CXL 10min组CDVA(矫正远视力,LogM AR)提高-0.21±0.23(t=2.735,P=0.026);最大角膜屈光力(Kmax)降低2.32±5.21D,但差异无统计学意义(t=1.40,P=0.193),低渗CXL组与I-CXL 5min组的UDVA、CDVA、Kmax稳定,差异均无统计学意义(P>0.05)。术后1wk时,分界线平均深度在各组分别为:低渗CXL组152.7±42.9μm,I-CXL 5min组213.6±42.3μm,I-CXL10min组237.0±46.4μm,组间比较,差异有统计学意义(F=7.111,P=0.006)。术后基质细胞的凋亡-活化-再生现象在I-CXL 10min组最明显。三组角膜最薄点厚度、角膜内皮细胞密度与术前比较,差异无统计学意义(P>0.05)。结论:三种经上皮CXL短期观察均能安全有效控制圆锥角膜病情的发展,其中离子导入10min胶原交联方法组织反应更显著。

荧光碳点的制备及其荧光特性的研究和应用

围绕具有优良荧光发光特性的无机纳米材料——碳点,设计一个本科化学实验。通过"自下而上"的方法分别制备蓝色、绿色荧光碳点溶液;考察荧光碳点溶液的荧光激发和发射光谱关系,相对法测定荧光量子产率;探究不同浓度和pH条件下的荧光光谱变化;并将荧光碳点应用到防伪技术领域,加深学生对荧光材料的相关荧光概念和表征手段如荧光激发光谱、荧光发射光谱、荧光量子产率,术语如Stokes位移和荧光影响因素等理论知识的理解,同时通过防伪应用开拓学生的思维,鼓励学生将课堂所学应用到实际生产生活中。

Chitosan conduits combined with nerve growth factor microspheres repair facial nerve defects

Microspheres containing nerve growth factor for sustained release were prepared by a compound method, and implanted into chitosan conduits to repair 10-mm defects on the right buccal branches of the facial nerve in rabbits. In addition, chitosan conduits combined with nerve growth factor or normal saline, as well as autologous nerve, were used as controls. At 90 days post-surgery, the muscular atrophy on the right upper lip was more evident in the nerve growth factor and normal sa- line groups than in the nerve growth factor-microspheres and autologous nerve groups. Electro- physiological analysis revealed that the nerve conduction velocity and amplitude were significantly higher in the nerve growth factor-microspheres and autologous nerve groups than in the nerve growth factor and normal saline groups. Moreover, histological observation illustrated that the di- ameter, number, alignment and myelin sheath thickness of myelinated nerves derived from rabbits were higher in the nerve growth factor-microspheres and autologous nerve groups than in the nerve growth factor and normal saline groups. These findings indicate that chitosan nerve conduits com- bined with microspheres for sustained release of nerve growth factor can significantly improve facial nerve defect repair in rabbits.

Consensus Control With a Constant Gain for Discrete-time Binary-valued Multi-agent Systems Based on a Projected Empirical Measure Method

This paper studies the consensus control of multiagent systems with binary-valued observations.An algorithm alternating estimation and control is proposed.Each agent estimates the states of its neighbors based on a projected empirical measure method for a holding time.Based on the estimates,each agent designs the consensus control with a constant gain at some skipping time.The states of the system are updated by the designed control,and the estimation and control design will be repeated.For the estimation,the projected empirical measure method is proposed for the binary-valued observations.The algorithm can ensure the uniform boundedness of the estimates and the mean square error of the estimation is proved to be at the order of the reciprocal of the holding time(the same order as that in the case of accurate outputs).For the consensus control,a constant gain is designed instead of the stochastic approximation based gain in the existing literature for binary-valued observations.And,there is no need to make modification for control since the uniform boundedness of the estimates ensures the uniform boundedness of the agents’states.Finally,the systems updated by the designed control are proved to achieve consensus and the consensus speed is faster than that in the existing literature.Simulations are given to demonstrate the theoretical results.

Endoscopic measurement of variceal diameter

AIM:To measure in vitro diameter of imitational varices using a self-made endoscopic scale and confirm its accuracy and clinical feasibility.METHODS:A catheter was introduced into the endoscopeaccessory channel and attached to a zebra wire guide that was used as a stylet.The wire guide was fixed onto the tip of the catheter by a soft and thin string.By gently advancing the stylet into the catheter,the width of the opening loop at the tip of the endoscope approximated the diameter of the imitational varices.Measurements performed in vitro using this self-made endoscopic ruler were compared to measurements of simulative varices.RESULTS:At the handle,the sleeve moving distance ranged from 5 to 14 mm.There was no obvious proportional relationship between the sleeve movement distance and endoscopic measurement ruler.The results indicated that the gap between the endoscopic measurement and actual measurement of the object size tended to close.The in vitro measurement of the diameter of the simulative varices showed that the two kinds of measuring methods were not significantly different with respect to their accuracy(P=0.8499).CONCLUSION:In vitro experiments confirmed that using a self-designed endoscopic ruler to measure the diameter of simulative varices was objective,accurate and feasible.