在晶状体损伤诱导的视神经长时程再生过程中MMP-12的表达规律

目的:探讨晶状体损伤诱导SD大鼠视神经钳压损伤后轴突长时程再生过程中MMP-12的表达变化。方法:建立SD大鼠视神经损伤模型和晶状体损伤模型,将实验动物24只分为对照组(仅开放眼眶暴露视神经)、晶状体损伤组、视神经损伤组、晶状体损伤联合视神经损伤组,每组各6只大鼠。采用有参转录组测序分析损伤视神经区域差异基因表达变化,筛选相关高表达差异基因,通过实时荧光定量PCR(qRT-PCR)和酶联免疫吸附实验(ELISA)定量分析损伤区MMP-12的表达量变化。结果:转录组测序主成因分析表明,晶状体损伤联合视神经损伤是基因表达变化中的主要成因。基因表达差异分析显示,晶状体损伤联合视神经损伤组中,存在MMP-12基因表达上调。在建模成功后14、21d时,晶状体损伤联合视神经损伤组的MMP-12 mRNA表达量与对照组、视神经损伤组和晶状体损伤组比较上调(P<0.05);在7、28d时,各组间表达无差异。在建模成功后7、14、21d时,晶状体损伤联合视神经损伤组的MMP-12蛋白表达量与对照组和视神经损伤组比较上调(P<0.05);21d时,晶状体损伤联合视神经损伤组与视神经损伤组比较上调(P<0.05)。28d时,各组间表达无差异。结论:MMP-12表达上调可能参与晶状体损伤后诱导视神经长时程再生过程。

Association between the Khorana risk score and all-cause mortality in Japanese patients with gastric and colorectal cancer: A retrospective cohort study

BACKGROUND The Khorana risk score(KRS)has poor predictive value for cancer-associated thrombosis in a single tumor type but is associated with early all-cause mortality from cancer.Evidence for the association between KRS and all-cause mortality in Japanese patients with gastric and colorectal cancer is limited.AIM To investigate whether KRS was independently related to all-cause mortality in Japanese patients with gastric and colorectal cancer after adjusting for other covariates and to shed light on its temporal validity.METHODS Data from Dryad database were used in this study.Patients in the Gastroen-terology Department of Sapporo General Hospital,Sapporo,Japan,were enrolled.The starting and ending dates of the enrollment were January 1,2008 and January 5,2015,respectively.The cutoff date for follow-up was May 31,2016.The inde-pendent and dependent(target)variables were the baseline measured using the KRS and final all-cause mortality,respectively.The KRS was categorized into three groups:Low-risk group(=0 score),intermediate-risk group(1-2 score),and high-risk group(≥3 score).RESULTS Men and patients with Eastern Cooperative Oncology Group Performance Status(ECOG PS)≥2 displayed a higher 2-year risk of death than women and those with ECOG PS 0-1 in the intermediate/high risk group for KRS.The higher the score,the higher the risk of early death;however,the relevance of this independent prediction decreased with longer survival.The overall survival of each patient was recorded via real-world follow-up and retrospective observations,and this study yielded the overall relationship between KRS and all-cause mortality.CONCLUSION The prechemotherapy baseline of KRS was independently associated with all-cause mortality within 2 years;however,this independent predictive relationship weakened as survival time increased.

Dynamical changing patterns of histological structure and ultrastructure of liver graft undergoing warm ischemia injury from non-heart-beating donor in rats

AIM： To investigate the histological and ultra-structural characteristics of liver graft during different of warm ischemia time （WIT） in rats and to predict the maximum limitation of liver graft to warm ischemia. METHODS： The rats were randomized into 7 groups undergoing warm ischemia injury for 0, 10, 15, 20, 30, 45 and 60 min, respectively. All specimens having undergone warm ischemia injury were investigated dynamically by light and electron microscopy, and histochemistry staining. After orthotopic liver transplantation （OLT）, the recovery of morphology of liver grafts after 6, 24 and 48 h was observed. RESULTS： The donor liver from non-heart-beating donors （NHBD） underwent ischemia injury both in the warm ischemia period and in the reperfusion period. Morphological changes were positively related to warm ischemia injury in a time-dependent manner during the reperfusion period. The results demonstrated that different degrees of histocyte degeneration were observed when WIT was within 30 min, and became more severe with the prolongation of WIT, no obvious hepatocyte necrosis was noted in any specimen. In the group undergoing warm ischemia injury for 45 min, small focal necrosis occurred in the central area of hepatic Iobule first. In the group undergoing warm ischemia injury for 60 rain, patchy or diffused necrosis was observed and the area was gradually extended, while hepatic sinusoid endothelial cells were obviously swollen. Hepatic sinusoid was obstructed and microcirculation was in disorder.CONCLUSION： The rat liver graft undergoing warm ischemia injury is in the reversible stage when the WIT is within 30 min. The 45 min WIT may be a critical point of rat liver graft to endure warm ischemia injury. When the WIT is over 60 min, the damage is irreversible.

Neuroprotective effects of long noncoding RNAs involved in ischemic postconditioning after ischemic stroke

During acute reperfusion,the expression profiles of long noncoding RNAs in adult rats with focal cerebral ischemia undergo broad changes.However,whether long noncoding RNAs are involved in neuroprotective effects following focal ischemic stroke in rats remains unclear.In this study,RNA isolation and library preparation was performed for long noncoding RNA sequencing,followed by determining the coding potential of identified long noncoding RNAs and target gene prediction.Differential expression analysis,long noncoding RNA functional enrichment analysis,and co-expression network analysis were performed comparing ischemic rats with and without ischemic postconditioning rats.Rats were subjected to ischemic postconditioning via the brief and repeated occlusion of the middle cerebral artery or femoral artery.Quantitative real-time reverse transcription-polymerase chain reaction was used to detect the expression levels of differentially expressed long noncoding RNAs after ischemic postconditioning in a rat model of ischemic stroke.The results showed that ischemic postconditioning greatly affected the expression profile of long noncoding RNAs and mRNAs in the brains of rats that underwent ischemic stroke.The predicted target genes of some of the identified long noncoding RNAs(cis targets)were related to the cellular response to ischemia and stress,cytokine signal transduction,inflammation,and apoptosis signal transduction pathways.In addition,15 significantly differentially expressed long noncoding RNAs were identified in the brains of rats subjected to ischemic postconditioning.Nine candidate long noncoding RNAs that may be related to ischemic postconditioning were identified by a long noncoding RNA expression profile and long noncoding RNA-mRNA co-expression network analysis.Expression levels were verified by quantitative real-time reverse transcription-polymerase chain reaction.These results suggested that the identified long noncoding RNAs may be involved in the neuroprotective effects associated with ischemic postconditioning following ischemic stroke.The experimental animal procedures were approved by the Animal Experiment Ethics Committee of Kunming Medical University(approval No.KMMU2018018)in January 2018.

Geological characteristics,metallogenic regularity,and research progress of lithium deposits in China

China is rich in abundant lithium resources characterized by considerable reserves and a concentrated distribution of metallogenic zones or belts,with proven reserves of 4046.8×10^(3) t(calculated based on Li_(2)O)by 2021.China is also a big consumer of lithium.By 2019,China’s lithium consumption in the battery sector alone had reached 99×10^(3) t,with an average annual growth rate of nearly 26%.China has become the world’s largest importer of lithium resources,showing a severely unbalanced relationship between supply and demand for lithium resources.Therefore,there is an urgent need for the prospecting,exploitation,and study of lithium resources in China.This study collected,organized,and summarized the data on the major lithium deposits in China,analyzed and compared the spatial-temporal distribution patterns,geological characteristics,and metallogenic regularity of these lithium deposits,and summarized the prospecting and research achievements over the last decade.The major lithium deposits in China are distributed in provinces and regions such as Qinghai,Jiangxi,Sichuan,Tibet,and Xinjiang.These deposits are mostly small in scale.According to different genetic types,this study divided lithium deposits into granitic pegmatite type,granite type,saline lake brine type,underground brine type,and sedimentary type,as well as new types including hot spring type and magmatic-hydrothermal type,and summarized the characteristics and key metallogenic factors of these different types of deposits.Sixteen metallogenic prospect areas of lithium deposits were delineated according to the deposit types and the distribution patterns of metallogenic belts.The paper introduced the research progress in major metallogenic models and lithium extraction techniques made over the past decade.Based on the comprehensive analysis of the prospecting potential of lithium deposits,the authors concluded that the future prospecting of lithium resources in China should focus on lithium metallogenic belts,the deep and peripheral areas of currently determined large-scale pegmatite-type lithium deposits,geophysical-geochemical anomalous areas with mineralization clues,and areas with developed large-scale low-grade associated granite-type and sedimentary lithium resources.The study aims to serve as a guide for the future prospecting of lithium deposits in China.

Effect of phosphorus on the microstructure and mechanical properties of strip cast carbon steel

Carbon steel strips with different phosphorus and carbon contents were produced by using the twin roll strip casting process. Fine grains and dendrite structure were observed in high-P steels. Negative phosphorus segregation was found in strip cast high-P and high-C steels. For the steels with different carbon contents, phosphorus distribution in the thickness direction of the strip is obviously different. This is because solutes are redistributed in the melting pool and the phosphorus segregation rate is associated with the length of the mushy zone and the phosphorus solubility in different phases. Phosphorus as a solute in ferrite can lead to the higher hardness and strength with lower plastic propertyies.

Establishment and Application of UFC-ACC Heat Transfer Coefficient Model

Based on medium plate runout table ultra-fast cooling( UFC)-accelerated cooling equipment( ACC) system,a heat transfer coefficient model was constructed. Firstly,according to the measured data,heat transfer coefficients under different roll speed and water volume were calculated by using an inverse heat conduction method. Secondly,a monofactorial heat transfer coefficient calculation formula was obtained. Finally,the heat transfer coefficient model based on medium plate runout table UFC-ACC system was constructed by intercept function,slope function,interaction influence function and linear or nonlinear influencing factors. The precision of these models was validated by comparing model prediction value with measured data,and the results were in good agreement with practical needs,and the average deviation was less than 5%.

The geographical distribution of grey wolves (Canis lupus) in China:a systematic review

The grey wolf （Canis lupus） is one of the most widely distributed terrestrial mammals, and its distribution and ecology in Europe and North America are largely well described. However, the distribution of grey wolves in southern China is still highly controversial. Several well-known western literatures stated that there were no grey wolves in southern China, while the presence of grey wolves across China has been indicated in A Guide to the Mammals of China, published by Princeton University Press. It is essential to solve this discrepancy since dogs may have originated from grey wolves in southern China. Therefore, we systematically investigated Chinese literatures about wild animal surveys and identified more than 100 articles and books that included information of the distribution of grey wolves in China. We also surveyed the collections of three Chinese natural museums and found 26 grey wolf skins specimens collected across China. Moreover, we investigated the fossil records in China and identified 25 archaeological sites with wolf remains including south China. In conclusion, with the comprehensive summary of Chinese literatures, museum specimens and fossil records, we demonstrate that grey wolves do distribute across all parts of the Chinese mainland, including the most southern parts.

Associations of gut microbiota with dyslipidemia based on sex differences in subjects from Northwestern China

BACKGROUND The gut microbiota(GM)has been proven to play a role in the regulation of host lipid metabolism,which provides a new theory about the pathogenesis of dyslipidemia.However,the associations of GM with dyslipidemia based on sex differences remain unclear and warrant elucidation.AIM To investigate the associations of GM features with serum lipid profiles based on sex differences in a Chinese population.METHODS This study ultimately recruited 142 participants(73 females and 69 males)at Honghui Hospital,Xi’an Jiaotong University.The anthropometric and blood metabolic parameters of all participants were measured.According to their serum lipid levels,female and male participants were classified into a high triglyceride(H_TG)group,a high total cholesterol(H_CHO)group,a low high-density lipoprotein cholesterol(L_HDL-C)group,and a control(CON)group with normal serum lipid levels.Fresh fecal samples were collected for 16S rRNA gene sequencing.UPARSE software,QIIME software,the RDP classifier and the FAPROTAX database were used for sequencing analyses.RESULTS The GM composition at the phylum level included Firmicutes and Bacteroidetes as the core GM.Different GM features were identified between females and males,and the associations between GM and serum lipid profiles were different in females and males.The GM features in different dyslipidemia subgroups changed in both female patients and male patients.Proteobacteria,Lactobacillaceae,Lactobacillus and Lactobacillus_salivarius were enriched in H_CHO females compared with CON females,while Coriobacteriia were enriched in L_HDL-C females.In the comparison among the three dyslipidemia subgroups in females,Lactobacillus_salivarius were enriched in H_CHO females,and Prevotellaceae were enriched in L_HDL-C females.Compared with CON or H_TG males,Prevotellaceae,unidentified_Ruminococcaceae,Roseburia and Roseburia_inulinivorans were decreased in L_HDL-C males(P value<0.05),and linear discriminant analysis effect size analysis indicated an enrichment of the above GM taxa in H_TG males compared with other male subgroups.Additionally,Roseburia_inulinivorans abundance was positively correlated with serum TG and total cholesterol levels,and Roseburia were positively correlated with serum TG level.Furthermore,Proteobacteria(0.724,95%CI:0.567-0.849),Lactobacillaceae(0.703,95%CI:0.544-0.832),Lactobacillus(0.705,95%CI:0.547-0.834)and Lactobacillus_salivarius(0.706,95%CI:0.548-0.835)could distinguish H_CHO females from CON females,while Coriobacteriia(0.710,95%CI:0.547-0.841),Coriobacteriales(0.710,95%CI:0.547-0.841),Prevotellaceae(0.697,95%CI:0.534-0.830),Roseburia(0.697,95%CI:0.534-0.830)and Roseburia_inulinivorans(0.684,95%CI:0.520-0.820)could discriminate H_TG males from CON males.Based on the predictions of GM metabolic capabilities with the FAPROTAX database,a total of 51 functional assignments were obtained in females,while 38 were obtained in males.This functional prediction suggested that cellulolysis increased in L_HDL-C females compared with CON females,but decreased in L_HDL-C males compared with CON males.CONCLUSION This study indicates associations of GM with serum lipid profiles,supporting the notion that GM dysbiosis may participate in the pathogenesis of dyslipidemia,and sex differences should be considered.

Ultrafast Electron Transfer in All-Small-Molecule Photovoltaic Blends Promoted by Intermolecular Interactions in Cyanided Donors

Cyano substitution has been established as a viable approach to optimize the performance of all-small-molecule organic solar cells.However,the effect of cyano substitution on the dynamics of photo-charge generation remains largely unexplored.Here,we report an ultrafast spectroscopic study showing that electron transfer is markedly promoted by enhanced intermolecular charge-transfer interaction in all-small-molecule blends with cyanided donors.The delocalized excitations,arising from intermolecular interaction in the moiety of cyano-substituted donor,undergo ultrafast electron transfer with a lifetime of∼3 ps in the blend.In contrast,some locally excited states,surviving in the film of donor without cyano substitution,are not actively involved in the charge separation.These findings well explain the performance improvement of devices with cyanided donors,suggesting that manipulating intermolecular interaction is an efficient strategy for device optimization.

Growth and Electronic Properties of Ag Nanoparticles on Reduced CeO2-x（111） Films

Ag nanoparticles grown on reduced CeO2-x thin films have been studied by X-ray plhotoelec- tron spectroscopy and resonant photoelectron spectroscopy of the valence band to understand the effect of oxygen vacancies in the CeO2-x thin films on the growth and interracial elec- tronic properties of Ag. Ag grows as three-dimensional particles on the CeO2-x （111） surface at 300 K. Compared to the fully oxidized ceria substrate surface, Ag favors the growth of smaller particles with a larger particle density on the reduced ceria substrate surface, which can be attributed to the nucleation of Ag on oxygen vacancies. The binding energy of Ag3d increases when the Ag particle size decreases, which is mainly attributed to the final-state screening. The interracial interaction between Ag and CeO2_x（lll） is weak. The resonant enhancement of the 4f level of Ce3＋ species in RPES indicates a partial Ce4＋--＋Ce3＋ reduction after Ag deposited on reduced ceria surface. The sintering temperature of Ag on CeO 1.85 （111） surface during annealing is a little higher than that of Ag on CeO2 （111） surface, indicating that Ag nanoparticles are more stable on the reduced ceria surface.

Re-evaluating data quality of dog mitochondrial,Y chromosomal,and autosomal SNPs genotyped by SNP array

Quality deficiencies in single nucleotide polymorphism （SNP） analyses have important implications. We used missingness rates to investigate the quality of a recently published dataset containing 424 mitochonddal, 211 Y chromosomal, and 160 432 autosomal SNPs generated by a semicustom Illumina SNP array from 5 392 dogs and 14 grey wolves. Overall, the individual missingness rate for mitochondrial SNPs was -43.8%, with 980 （18.1%）individuals completely missing mitochondrial SNP genotyping （missingness rate=l）. In males, the genotype missingness rate was -28.8% for Y chromosomal SNPs, with 374 males recording rates above 0.96. These 374 males also exhibited completely failed mitochondrial SNPs genotyping, indicative of a batch effect. Individual missingness rates for autosomal markers were greater than zero, but less than 0.5. Neither mitochondrial nor Y chromosomal SNPs achieved complete genotyping （locus missingness rate=0）, whereas 5.9% of autosomal SNPs had a locus missingness rate=l. The high missingness rates and possible batch effect show that caution and rigorous measures are vital when genotyping and analyzing SNP array data for domestic animals. Further improvements of these arrays will be helpful to future studies.

Efficiency of collective myosin Ⅱ motors studied with an elastic coupling power-stroke ratchet model

We proposed a modified ratchet model including power-stroke and elastic coupling to study the efficiency of collective non-processive motors such as myosin Ⅱ in muscle. Our theoretical results are in good agreement with the experimental data. Our study not only reveals that the maximum efficiency depends on elasticity and is independent of transition rates but also indicates that the parameters fitted to fast muscle are different from those fitted to a slow one. The latter may imply that the structure of the fast muscle is different from that of the slow one. The main reason that our model succeeds is that velocity in this model is an independent variable.

Discoid medial meniscus of both knees:A case report

BACKGROUND Discoid meniscus is a congenital anomaly that typically affects the lateral meniscus.The appearance of the discoid medial meniscus in both knees is extremely rare,with an incidence of only 0.012%.CASE SUMMARY Our patient was a 30-year-old female.Under no obvious predisposing causes,she began to experience pain in both knees,which worsened while walking and squatting.The pain was aggravated after exercise,and joint flexion and extension activities were accompanied by knee snapping.Apley’s test was positive on physical examination,and there was a pressing pain in the medial articular space.Plain radiographs of both knees revealed no obvious abnormalities in the bilateral knee joint space.Partial meniscectomy as well as menisci reformation were performed on both knees under arthroscopy.Under the guidance of rehabilitation,the patient’s range of motion in both knees returned to normal without pain and knee snapping.CONCLUSION This study showed that the clinical manifestations of the discoid medial meniscus injury are identical to those of the conventional medial meniscus injury,and arthroscopic surgery is effective.

Ligament augmentation reconstruction system artificial ligaments in patellar tendon reconstruction-a chronic patellar tendon rupture after multiple operations: A case report

BACKGROUND Patellar tendon rupture is a rare disease,and reports regarding patellar tendon reconstruction with ligament augmentation reconstruction system(LARS)ligaments are limited,with only three reports available in the literature.LARS ligaments are made of polyethylene terephthalate and have been certified as a more favorable option than other tendon transplants.To our knowledge,this is the first report of patellar tendon reconstruction with LARS for suture fixation due to poor quality of the tendon after multiple operations to enable early mobilization and quick rehabilitation.CASE SUMMARY A 65-year-old woman had limited ability in extending her leg and an inability to perform a straight leg raise after multiple operations due to patella fracture.The patient underwent patellar tendon reconstruction with LARS artificial ligaments.After 12 mo of follow-up,the patient was able to perform a straight leg raise,and the incision healed well without complications.The Lysholmscore was 95 and the range of motion of the knee was 0-130°.CONCLUSION This study revealed that patellar tendon reconstruction with LARS artificial ligaments is possible in a patient with a patellar tendon rupture who required rapid postoperative recovery.

Fast compression and reconstruction of astronomical images based on compressed sensing

With the fast increase in the resolution of astronomical images, the question of how to process and transfer such large images has become a key issue in astronomy. We propose a new real-time compression and fast reconstruction algorithm for astronomical images based on compressive sensing techniques. We first reconstruct tile Original signal with fewer measurements, according to its compressibility. Then, based on the characteristics of astronomical images, we apply Daubechies orthogonal wavelets to obtain a sparse representation. A matrix representing a random Fourier ensembleis used to obtain a sparse representation in a lower dimensional space. For reconstructing the image, we propose a novel minimum total variation with block addptive sensing to balance the accuracy and eomputation time. Our experimental results show that the proposed algorithm can efficiently reconstruct colorful astronomicai images with high resolution and improve the applicability of compressed sensing.

Hydrogen Embrittlement of Advanced High-Strength Steel for Automobile Application:A Review

The hydrogen embrittlement(HE)fracture of advanced high-strength steels used in lightweight automobiles has received increasing public attention.The source,transmission,and movement of hydrogen,characterization parameters,and test methods of HE,as well as the characteristics and path of HE fractures,are introduced.The mechanisms and modes of crack propagation of HE and hydrogen-induced delayed fracture are reviewed.The recent progress surrounding micro and macro typical fracture characteristics and the influencing factors of HE are discussed.Finally,methods for improving HE resistance can be summarized as follows:(1)reducing crystalline grain and inclusion sizes(oxides,sulfides,and titanium nitride),(2)controlling nano-precipitates(niobium carbide,titanium carbide,and composite precipitation),and(3)increasing residual austenite content under the reasonable tension strength of steel.

Modeling flow stress and grain size of GCr15 bearing steel at hightemperature deformation near end of solidification

Hot-core heavy reduction rolling is an innovative technology for continuous casting billet at the end of solidification.The deformation characteristics of GCr15 bearing billet were investigated over the temperature range of 1000-1300℃ with the strain rate of 0.001-10 s^(-1) by the Gleeble 3800 thermo-mechanical simulator.Firstly,the true stress-strain data are calibrated by the friction correction method to acquire accurate parameters near the solidus.Then,the Laasraoui-type constitutive model and dynamic austenite grain size model are established by the thermal compression results and corrosion experimental results,and the predicted values of the experimental interval are obtained by using the models.Meanwhile,the accuracy of models is verified by comparing the predicted curves with the experimental data.Last but not the least,the dynamic parameters between solidus and liquidus are predicted by the two models,and the difficulty of experimental collecting near the melting point is solved.

Microstructure and Abrasive Wear Behavior of Medium Carbon Low Alloy Martensitic Abrasion Resistant Steel

The effect of processing parameters such as hot rolling and heat treatment on microstructure and mechanical properties was investigated for a new 0.27mass% C and Ni, Mo-free low alloy martensitic abrasion resistant steel. The three-body impact abrasive wear behavior was also analyzed. The results showed that two-step controlled rolling besides quenching at 880 ℃ and tempering at 170 ℃ could result in optimal mechanical property., the Brinell hardness, tensile strength, elongation and --40 ℃ impact toughness were 531, 1530 MPa, 11.8% and 58 J, re- spectively. The microstructure was of fine lath martensite with little retained austenite. Three-body impact abrasive wear results showed that wear mechanism was mainly of plastic deformation fatigue when the impact energy was 2 J, and the relative wear resistance was 1.04 times higher than that of the same grade compared steel under the same working condition. The optimal hardness and toughness match was the main reason of higher wear resistance.

Stable Real-Time Surgical Cutting Simulation of Deformable Objects Embedded with Arbitrary Triangular Meshes

Surgical simulators need to simulate deformation and cutting of deformable objects. Adaptive octree mesh based cutting methods embed the deformable objects into octree meshes that are recursively refined near the cutting tool trajectory. Deformation is only applied to the octree meshes; thus the deformation instability problem caused by degenerated elements is avoided. Biological tissues and organs usually contain complex internal structures that are ignored by previous work. In this paper the deformable objects are modeled as voxels connected by links and embedded inside adaptive octree meshes. Links swept by the cutting tool are disconnected and object surface meshes are reconstructed from disconnected links. Two novel methods for embedding triangular meshes as internal structures are proposed. The surface mesh embedding method is applicable to arbitrary triangular meshes, but these meshes have no physical properties. The material sub-region embedding method associates the interiors enclosed by the triangular meshes with physical properties, but requires that these meshes are watertight, and have no self-intersections, and their smallest features are larger than a voxel. Some local features are constructed in a pre-calculation stage to increase simulation performance. Simulation tests show that our methods can cut embedded structures in a way consistent with the cutting of the deformable objects. Cut fragments can also deform correctly along with the deformable objects.