骨肌串扰防治骨肌共减症的作用及机制

骨肌共减症(osteosarcopenia,OS)是一种常见的老年退行性综合症,表现为个体在衰老过程中骨量和肌肉含量同时减少,引起骨质疏松症和肌少症,导致机体平衡能力下降,容易跌倒、骨折,严重威胁老年人的生活质量和生存寿命。由于骨骼和肌肉都属于运动系统,骨质疏松症与肌少症在遗传、内分泌、旁分泌和脂肪浸润方面有共同的致病因素,彼此相互影响、相互调节。因此,本文综述了诱导骨肌共减症的力学串扰、细胞因子串扰、信号通路间相互串扰的分子机制和临床诊断方法,通过运动、营养和药物的干预,对提高老年人的寿命和生存质量,实践“健康老龄化”具有重要的意义。

探讨“骨正筋和、形神共调”康复原则在慢性肌骨功能障碍中的应用

慢性肌骨功能障碍涉及全身各部位,影响患者的运动功能、日常活动及生活质量。肌骨障碍的主要病机为筋骨失衡、形神失调,具体表现为骨不正、筋不和的形体障碍及神散形坏的情绪认知及运动协调障碍等。“骨不正”表现包括关节对线不良和骨代谢的异常,影响形的活动度、稳定性及其控制能力,产生骨痹、骨痿等障碍;“筋不和”表现肌肉张力、质量、力量改变和肌群协调性异常、肌肉代谢失衡等,导致筋痿、筋痹、筋挛等障碍;形神不调表现为情绪认知改变及神经肌肉的运动控制障碍,导致筋骨控制的失常,形神功能难以相应,筋骨失衡与形神失调之间相互影响。根据肌骨康复的原理,结合中医康复对筋骨和形神功能的认识,提出“骨正筋和、形神共调”的康复原则。“骨正”为骨髓坚固、关节清利,保持关节良好的对线对位并保持正常的骨代谢平衡;“筋和”指关节周围的相关肌群、韧带等软组织具备良好的柔韧性和均衡的力量,肌群之间在运动和稳定中发挥协调的作用,同时肌肉代谢正常,即筋的形质和功能均维持在和谐的状态。骨正提供结构支撑和稳定的功能,“骨正则形健”,也与筋和提供的驱动关节活动和稳定协调关节运动的作用——“筋和则形康”相辅相成。“形神共调”指在骨正筋和的调控过程中,需要神经系统对关节活动、肌群激活及其协调性的正确控制,也需要情绪认知的良好配合,体现神明形安促进运动控制能力对筋骨平衡的重要性,实现“调神以御形”“全形以治神”。此外,中医康复疗法如传统运动、针灸、手法等均体现对筋骨平衡、调形治神的重要性。“骨正筋和、形神共调”是中医康复整体功能观的体现,也是适用于肌骨功能障碍的主动康复原则,有助于中西医结合康复发挥精准康复的优势和整体康复的特色。

定量磁共振成像在关节软骨中的应用研究进展

在临床上,关节软骨损伤是一种常见病,其发生发展可由外伤、骨性关节炎(osteoarthritis, OA)以及剥脱性骨软骨炎等原因造成,而且这种损坏发生后很难修复。关节软骨损伤主要表现为关节疼痛及功能障碍,关节软骨的损伤以及退变都不同程度地发生在老年人及长期剧烈运动的人群中。关节镜检查被认为是诊断关节软骨病变的金标准。但由于其有创检查的性质,对检查者的技术水平要求很高,且无法深入了解软骨的内部情况。定量磁共振成像(quantitative magnetic resonance imaging, qMRI)既可显示软骨形态学变化,又可以定量评估软骨的生化成分,由于该技术具有无创、良好的软组织分辨力、多参数、多平面成像的优势,它能以非侵入性的定量测量来敏感地监测软骨的微细变化,提供可靠和可重复的成像生物标志物。

掺锶锌涂层与成骨/巨噬细胞共培养体系对血管内皮细胞的影响

探究掺锶锌微孔涂层及成骨/巨噬细胞共培养体系对血管内皮细胞增殖、迁移的影响。方法 微弧氧化制备含锶、锌元素的微孔钛片,场发射扫描电子显微镜和能谱分析检测涂层理化性质,并制备该涂层浸提液。小鼠胚胎成骨细胞前体细胞和小鼠单核巨噬细胞白血病细胞共培养,并制备共培养上清液。培养人脐静脉内皮细胞,根据培养基不同分为六组:A组,30 %涂层浸提液+ 70 %内皮细胞完全培养基;B组,30 %共培养上清液+ 70 %内皮细胞完全培养基;C组:30 %涂层浸提液+ 30 %共培养上清液+ 40 %内皮细胞完全培养基;D - F组,为A - C组的内皮细胞完全培养基换成内皮细胞无血清培养基,其余成分一致。应用CCK - 8试剂盒和细胞划痕实验分别检测前三组细胞增殖和后三组细胞迁移情况。结果 场发射扫描电子显微镜检测显示微弧氧化制备的掺锶锌钛片表面有均匀分布的孔洞;能谱分析检测显示锶、锌元素成功掺入涂层中;CCK - 8细胞增殖检测显示B组人脐静脉内皮细胞增殖最高,其次为C组,再次为A组(p < 0.05);划痕实验显示F组细胞迁移最快,D组最慢(p < 0.05),E组与F组差异无统计学意义。结论 成骨/巨噬细胞共培养体系更有利于人脐静脉内皮细胞的增殖,锶锌微孔涂层与共培养体系二者联合应用更有利于细胞迁移。

Environmentally benign and economic synthesis of covalent triazine-based frameworks

Covalent triazine-based frameworks（CTFs） are important microporous materials with a wide range of applications.Here,we demonstrate an environmentally benign and economic synthetic pathway to CTFs.The monomers used for CTFs,aromatic nitriles,were obtained by cyanation using nontoxic potassium hexacyanoferrate（Ⅱ） in place of commonly used toxic cyanides.Then,the CTFs were synthesized by trimerization of the corresponding cyano monomers in molten zinc chloride.A series of CTFs was synthesized,and the highest Brunauer-Emmett-Teller surface area measured in this series was 2404 m^2/g.Among the synthesized CTFs,CTF_（DCP） exhibited excellent CO_2 adsorption properties,with a CO_2 uptake of 225 mg/g at 0℃.

Magnetic Resonance Imaging Findings of Temporal Lobe Radiation Encephalopathy in Nasopharyngeal Carcinoma

Objective： To observe the magnetic resonance imaging （MRI） morphological features of radiation encephalopathy （REP） in nasopharyngeal carcinoma （NPC） and investigate their diagnostic value. Methods： The MRI data of 160 lesions from 104 NPC patients with the diagnosis of temporal lobe REP were retrospectively analyzed. The MRI was performed after radiation therapy of NPC with an interval ranged from 8 months to 13 years. The imaging sequences included T1-weighted imaging and T2-weighted imaging. Additionally T1-weighted imaging with injection of the contrast agent of Gd-DTPA was performed in 111 lesions and fluid attenuated inversion recovery （FLAIR） was performed on 37 lesions, and among them, 2 cases were subjected to MR perfusion weighted imaging （PWI）. Results： Unilateral temporal lobe was involved in 48 cases of REP, bilateral temporal lobe in 56 cases of REP respectively, with a total of 160 lesions. The REP in the white matter displayed hyper-intensity signal on T2-weighted imaging which could be homogenous, whereas areas with heterogeneous hypo-intensity signal could be seen in 59 of them otherwise with hyper-intensity signal, and 91 lesions of white matter were associated with gray matter lesions with an appearance of hypo-intensity signal on T1-weighted imaging and hyper-intensity signal on T2-weighted imaging. In 111 lesions with the Gd-DTPA enhanced T1-weigthed imaging, 91 showed the enhancement of brain parenchyma. Hemorrhage and hemosiderosis occurred in 5 lesions of REP. Conclusion： REP in NPC has a multiplicity of the imaging features on MRI, in addition to the common involvement of white matter, including other relatively frequent findings, such as the involvement of gray matter, hemorrhage, hemosiderosis and blood-brain barrier destruction, those could be clearly revealed on MRI.

A new strategy for the fabrication of covalent organic framework‐metal‐organic framework hybrids via in‐situ functionalization of ligands for improved hydrogen evolution reaction activity

The development of novel porous materials have attracted significant attention owing to its possible application in several fields.In this study,we designed a novel covalent organic framework‐metal‐organic framework(COF‐MOF)material through an in‐situ ligand self‐assembly method.The in‐situ modified ligands not only act as nucleation sites to form Ti‐MOF,but also as a channel to rapidly transfer photogenerated electrons without introducing additional chemical bonds.The photocatalytic hydrogen production rate achieved over B‐CTF‐Ti‐MOF(1:1)was 1975μmol·g^(–1)·h^(–1) with an apparent quantum efficiency of 4.76%,which is 11.8 times higher than that of the pure CTF‐1.In addition,compared with the sample prepared by separating the ligands(CTF‐1/Ti‐MOF),B‐CTF‐Ti‐MOF shows excellent activity and stability.Finally,a reasonable photocatalytic mechanism was proposed using the results of electrochemical tests and spectral analyses.This study provides a universal method for the construction of highly efficient and stable COF/MOF materials with excellent properties.

Asymmetric photocatalysis over robust covalent organic frameworks with tetrahydroquinoline linkage

The asymmetric photocatalytic organic synthesis(APOS)process is a sustainable and environmentally benign method for the production of optically active chemicals with sunlight as an energy source.However,it still lacks efficient semiconductors with tunable band structures and has a low recycling stability.Herein,we report the synthesis of tetrahydroquinoline-linked covalent organic frameworks(QH-COFs)with irreversible tetrahydroquinoline linkage as efficient semiconductors for the visible-light-driven asymmetricα-alkylation of aldehydes by merging with a chiral secondary amine.Up to 94%ee was obtained over QH-COFs,and the activity of QH-COFs was significantly higher than those of inorganic semiconductors(e.g.,Ti O2,Bi VO4,and WO3)under similar conditions,which is mainly attributed to their narrow band gap and suitable band edge.As far as we know,QH-COFs are the most active semiconductors for asymmetricα-alkylation of aldehydes ever reported.The QH-COFs were prepared via a one-pot Povarov cascade imine formation and cycloaddition reaction using Sc(OTf)3/Yb(OTf)3 as Lewis acid catalysts.Attributed to the tetrahydroquinoline linkage,QH-COFs showed extremely high recycling stability,which made practicals application possible.This work not only opens up a new avenue for asymmetric photocatalysis but also provides an efficient and general method for the construction of robust COFs.

2D metal‐free heterostructure of covalent triazine framework/g‐C_(3)N_(4) for enhanced photocatalytic CO_(2) reduction with high selectivity

Solar‐driven CO_(2)conversion to precious fossil fuels has been proved to become a potential way to decrease CO_(2)with producing renewable fuels,which mainly relies on photocatalysts with efficient charge separation.In this work,a metal free heterostructure of covalent triazine framework(CTF)and graphite carbon nitride(g‐C_(3)N_(4),abbreviated as CN)is applied in the CO_(2)photoreduction for the first time.Detailed characterization methods such as photoluminescence(PL)and time‐resolved PL(TR‐PL)decay are utilized to reveal the photo‐induced carries separating process on g‐C_(3)N_(4)/CTF(CN/CTF)heterostructure.The introduced CTF demonstrated a great boosting photocatalytic activity for CN,bringing about the transform rates of CO_(2)to CO reaching 151.1μmol/(g·h)with a 30 h stabilization time,while negligible CH_(4)was detected.The optimal CN/CTF heterostructure could more efficiently separate charges with a lower probability of recombination under visible light irradiation,which made the photoreduction efficiency of CO_(2)to CO be 25.5 and 2.5 times higher than that of CTF and CN,respectively.This investigation is expected to offer a new thought for fabricating high‐efficiency photocatalyst without metal in solar‐energy‐driven CO_(2)reduction.

AGE-RELATED CHANGES OF BONE MARROW OF NORMAL ADULT MAN ON DIFFUSION WEIGHTED IMAGING

Objective To investigate the signal intensity and apparent diffusion coefficient (ADC) of bone marrow of normal adult man on diffusion weighted imaging (DWI). Methods Fifteen healthy volunteers and thirty-eight patients with benign prostatic hyperplasia or normal prostate were enrolled in this study, with age range 28-82 years old (mean 55.26 ± 18.05 years). All people were examined with large field DWI on a 3.0T magnetic resonance scanner, which ranges from the top of head to the lower limb. The signal-to-noise ratio (SNR) on the DWI and ADC of lumber vertebra at renal hilum level, left ilium and superior segment of left femur were measured. The measured SNR and ADC value of the above sites were compared by one way analysis of variance and their correlations with age were investigated by Pearson's correlation analysis. Results The SNR of lumber vertebra, left ilium and left femur showed no significant difference (F = 0.271, P = 0.763). The SNR of lumber vertebra (r = 0.309, P = 0.024) and left ilium (r = 0.359, P = 0.008) showed positive correlation with age, while the SNR of left femur showed no correlation with age (r = -0.163, P = 0.283). The ADC of lumber vertebra [(0.617 ± 0.177) ×10-3 mm2/s] was significantly higher than that of left ilium [(0.404 ± 0.112) ×10-3 mm2/s, P < 0.001] and left femur [(0.362 ± 0.092) ×10-3 mm2/s, P < 0.001], while the ADC of left ilium and left femur had no significant difference. The ADC of lumber vertebra, left ilium and left femur showed no correlation with age. Conclusion Understanding of age-related changes of normal adult bone marrow on DWI is very important to differentiate the normal bone marrow and abnormal lesions.

FEASIBILITY OF WHOLE BODY DIFFUSION WEIGHTED IMAGING IN DETECTING BONE METASTASIS ON 3.0T MR SCANNER

Objective To evaluate the feasibility of whole body diffusion weighted imaging (DWI) in bone metastasis detection using bone scintigraphy as comparison. Methods Forty-five patients with malignancy history were enrolled in our study. All the patients received the whole body DWI and bone scintigraphy scan within 1 week. The magnetic resonance (MR) examination was performed on 3.0T MR scanner using embedded body coil. The images were reviewed separately by two radiologists and two nuclear medicine physicians, who were blinded to the results of the other imaging modality. The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of the two techniques for detecting bone metastasis were analyzed. Results A total of 181 metastatic lesions in 77 regions of 34 patients were detected by whole body DWI, and 167 metastatic lesions in 76 regions of 31 patients were identified by bone scintigraphy. The patient-based sensitivity and PPV of whole body DWI and bone scintigraphy were similar (89.5% vs. 81.6%, 97.1% vs. 91.2%), whereas, the patient-based specificity and NPV of whole body DWI were obviously higher than those of bone scintigraphy (85.7% vs. 57.1%, 60.0% vs. 36.4%). Ten regions negative in scintigraphy but positive in whole body DWI, mainly located in spine, pelvis, and femur; nine regions only detected by scintigraphy, mainly located in skull, sternum, clavicle, and scapula. The region-based sensitivity and specificity of whole body DWI were slightly higher than those of bone scintigraphy (89.5% vs. 88.4%, 95.6% vs. 87.6%). Conclusion Whole body DWI reveals excellent concordance with bone scintigraphy regarding detection of bone metastasis, and the two techniques are complementary for each other.

Direct and Indirect Excitons in Two-Dimensional Covalent Organic Frameworks

Highly luminescent bulk two-dimensional covalent organic frameworks(COFs)attract much attention recently.Origin of their luminescence and their large Stokes shift is an open question.After first-principles calculations on two kinds of COFs using the GW method and Bethe-Salpeter equation,we find that monolayer COF has a direct band gap,while bulk COF is an indirect band-gap material.The calculated optical gap and optical absorption spectrum for the direct excitons of bulk COF agree with the experiment.However,the calculated energy of the indirect exciton,in which the photoelectron and the hole locate at the conduction band minimum and the valence band maximum of bulk COF respectively,is too low compared to the fluorescence spectrum in experiment.This may exclude the possible assistance of phonons in the luminescence of bulk COF.Luminescence of bulk COF might result from exciton recombination at the defects sites.The indirect band-gap character of bulk COF originates from its AA-stacked conformation.If the conformation is changed to the AB-stacked one,the band gap of COF becomes direct which may enhance the luminescence.

Amide-linked covalent organic frameworks as efficient heterogeneous photocatalysts in water

Semiconductor photocatalysts play an indispensable role in the photocatalytic process.Two-dimensional covalent organic frameworks(2D-COFs),as a kind of innovative photocatalyst,have garnered tremendous attention.Herein,we report an amide-linked 2D-COF(COF-JLU19)with outstanding photocatalytic performance in water,designed through a multi-synergistic approach.The synergistic effects of the high porosity,photoactive framework,high wettability,and stability of COF-JLU19 led to an unprecedented enhancement in the photocatalytic activity and recyclability in water upon illumination by visible light.More importantly,amide-linked 2D-COF based electrospinning membranes were prepared,which also exhibited superior photocatalytic activity for the degradation of Rhodamine B in water with sunlight.This study highlights the potential of the multi-synergistic approach as a universal rule for developing COF-based photocatalysts to address environmental and energy challenges.

CO-TRANSFECTION OF RAT BONE MARROW MESENCHYMAL STEM CELLS WITH HUMAN BMP2 AND VEGF165 GENES

Objective To explore the feasibility and efficacy of lentivirus-mediated co-transfection of rat bone marrow mesenchymal stem cells （MSCs） with human vascular endothelial growth factor 165 （hVEGFI65） gene and human bone morphogenetic protein 2 （hBMP2） gene. Methods The hVEGF165 and hBMP2 cDNAs were obtained from human osteosarcoma cell line MG63 and cloned into lentiviral expression vectors designed to co-express the copepod green fluorescent protein （copGFP）. The expression lentivector and packaging Plasmid Mix were co-transferred to 293TN cells, which produced the lentivirus carrying hVEGF165 （Lv-VEGF） or hBMP2 （ Lv-BMP） , respectively. MSCs of Wistar rats were co-transfected with Lv-BMP and Lv-VEGF （BMP ＋ VEGF group）, or each alone （BMP group and VEGF group）, or with no virus （ Control group）. The mRNA and protein expressions of hVEGF165 and hBMP2 genes in each group were detected by real-time PCR and enzyme linked immunosorbent assay （ELISA）. Results Lentiviral expression vectors carrying hVEGF165 or hBMP2 were correctly constructed and confirmed by restriction endonucleses analysis and DNA sequencing analysis. A transfer efficiency up to 90% was archieved in all the transfected groups detected by the fraction of fluorescent cells using fluorescent microscopy. From the results generated by real-time PCR and ELISA, VEGF165 and BMP2 genes were co-expressed in BMP ＋ VEGF group. No significant difference of BMP2 expression was detected between BMP ＋ VEGF and BMP groups （ P 〉 0. 05）. Similarly, there was no significant difference of VEGF165 expression between BMP ＋ VEGF and VEGF groups （ P 〉 0. 05）. Conclusion VEGF165 and BMP2 genes were successfully co-expressed in MSCs by lentivirus-mediated co-transfection, which provided a further foundation for the combined gene therapy of bone regeneration.

Ionic covalent organic frameworks for highly effective catalysis

As an emerging class of crystalline porous materials, covalent organic frameworks（COFs） have been widely used as catalysts or catalyst supports. Flexible regulation of the pores and easy introduction of functional active sites onto the skeleton of COFs make them promising platforms for many catalysis applications. However, only a single function is generally observed in these COFs. Herein, we synthesized a negatively charged ionic COF（I-COF） and successfully incorporated functionalized counter ions, that is, metallic Mn2＋ and a coordination complex of manganese（Ⅱ） bipyridine complexes（[Mn（bpy）2]2＋）, via a simple ion exchange process. The resulting I-COFs can act as effective heterogeneous catalysts for epoxidation reactions. We envisage that with this type of ionic architecture, a variety of other functional cations could be exchanged into the frameworks, thus making the COF a versatile platform for different applications.

AGGREGATE IMAGE BASED TEXTURE IDENTIFICATION USING GRAY LEVEL CO-OCCURRENCE PROBABILITY AND BP NEURAL NETWORK

Classifying the texture of granules in 2D images has aroused manifold research atten-tion for its technical challenges in image processing areas.This letter presents an aggregate texture identification approach by jointly using Gray Level Co-occurrence Probability(GLCP) and BP neural network techniques.First, up to 8 GLCP-associated texture feature parameters are defined and computed, and these consequent parameters next serve as the inputs feeding to the BP neural network to calculate the similarity to any of given aggregate texture type.A finite number of aggregate images of 3 kinds, with each containing specific type of mineral particles, are put to the identification test, experimentally proving the feasibility and robustness of the proposed method.

HISTOMORPHOMETRIC STUDY OF SUBCHONDRAL BONE OF NECROTIC FEMORAL HEAD IN RABBITS INDUCED BY METHYLPREDNISOLONE COMBINED WITH LOW-DOSE LIPOPOLYSACCHARIDE

Objective To investigate the histomorphometric features of the necrotic femoral head of rabbits induced by methylprednisolone combined with lipopolysaccharide. Methods Thirty-two mole adult New Zealand white rabbits were used. Among them, 16 were injected with lipopolysaccharide and methylprednisolone （ osteonecrosis group） , and another 16 were sham-injected with saline （ control group）. Magnetic resonance （MR） imaging was taken for femoral heads of the rabbits in both groups at the end of 2, 4 and 6 weeks after the injection. All the rabbits were then killed 6 weeks later. The femoral heads of the rabbits were collected and processed for histological and histomorphometric analysis. Results Femoral head necrosis occurred in 14 rabbits of the osteonecrosis group which were confirmed by histological evaluation and MR imaging. Osteonecrotic femoral heads, compared to controls, were characterized by lower values of bone volume/tissue volume （ P 〈 0. 01 ）, tabecular thichness （ P 〈 0. 01 ） , osteoid surface/bone surface （ P 〈 0. 05 ）, mineralizing apposition rate （ P 〈 0 05 ）, and bone formation rate/bone surface （ P 〈0. 05 ）. However, tabecular separation and eroded surface/bone surface were higher in osteonecrotic femoral heads than in controls （ P 〈 0. 01 ）. Trabecular number and osteoclast surface/ bone surface did not differ significantly. Conclusion The results demonstrated that osteoporosis was apparent in osteonecrotic femoral heads induced by methylprednisolone and lipopolysaccharide, due mainly to trabecular thinning rather than reduction of trabecular number. This might be due to reduced bone formation combined with increased bone resorption.

DFT study of CO_(2)electrochemical reduction on two-dimensional metal-based covalent organic frameworks

CO_(2)electrochemical reduction(CO_(2)ER)to high-value fuels and chemicals is a promising strategy for using CO_(2)as a carbon source.However,the large-scale application of CO_(2)ER is limited by the lack of efficient and selective electrocatalysts.By means of density functional theory(DFT)calculations,the potential of transitional metal-based covalent organic frameworks(TM-COFs,TM=Fe,Co,Ni,Cu,Zn,Ru,Rh,Pd,and Ag)as CO_(2)reduction electrocatalysts was systematically studied.The results show that the single TM atom can be firmly anchored on COFs for forming stable single-atom catalysts.The TM atom in phthalocyanine has excellent catalytic activity towards CO_(2)ER,while the pyridine N in pyrazine is the active site of the hydrogen evolution reaction(HER).Among studied candidates,Co-COF and Rh-COF are predicted to have limiting potential of-0.66/-0.11 and-0.49/-0.49 V for CO_(2)ER/HER,respectively.The present study may provide a new strategy for designing novel bifunctional catalysts.

当手指被甲鱼咬住之后

冬冬今年6岁,上小学一年级,他脑子灵,手也巧,还对小动物特别感兴趣,只要有机会就喜欢与小狗、小猫在一起玩耍。暑假的一天,妈妈带冬冬去农贸市场买菜,当他看到一位菜农的盆里有几只甲鱼时,高兴极了,他不知甲鱼的厉害,立即伸手去抓那只头伸得老高的甲鱼。说时迟那是快,甲鱼见冬冬的手伸过来,立即张开血口把他的手紧紧咬住不放,冬冬痛得哭叫起来。

立足企业特点 开展国防教育

企业开展国防教育,这是落实党的十三大关于“加强国防教育,提高人民的国防观念”一个实际行动,也是《全民所有制工业企业法》赋予企业的一项职责和义务。企业开展国防教育,在组织形式和内容方法上,都必须与生产实际相结合,适合企业自身的特点。