ObjectiveBola-like short peptides exhibit novel self-assembly properties due to the formation of peptide dimers via hydrogen bonding interactions between their C-terminals. In this configuration, hydrophilic amino acids are distributed at both terminals, making these peptides behave similarly to Bola peptides. The electrostatic repulsive interactions arising from the hydrophilic amino acids at each terminal can be neutralized, thereby greatly promoting the lateral association of β-sheets. Consequently, assemblies with significantly larger widths are typically the dominant nanostructures for Bola-like peptides. To investigate the effect of hydrophilic amino acids on the self-assembly behavior of Bola-like peptides, the peptides Ac-RI₃-CONH₂ and Ac-HI₃-CONH₂ were designed and synthesized using the Bola-like peptide Ac-KI₃-CONH₂ as a template. Their self-assembly behavior was systematically examined. MethodsAtomic force microscopy (AFM) and transmission electron microscopy (TEM) were employed to characterize the morphology and size of the assemblies. The secondary structures of the assemblies were analyzed using circular dichroism (CD) and Fourier transform infrared (FTIR) spectroscopy. Small-angle neutron scattering (SANS) was used to obtain detailed structural information at a short-length scale. Based on these experimental results, the effects of hydrophilic amino acids on the self-assembly behavior of Bola-like short peptides were systematically analyzed, and the underlying formation mechanism was explored. ResultsThe aggregation process primarily involved three steps. First, peptide dimers were formed through hydrogen bonding interactions between their C-terminals. Within these dimers, the hydrophilic amino acids K, R, and H were positioned at both terminals, enabling the peptides to self-assemble in a manner similar to Bola peptides. Next, β-sheets were formed via hydrogen bonding interactions along the peptide backbone. Finally, self-assemblies were generated through the lateral association of β-sheets. The results demonstrated that both Ac-KI₃-CONH₂ and Ac-RI₃-CONH₂ could self-assemble into double-layer nanotubes with diameters of approximately 200 nm. These nanotubes were formed by the edge fusion of helical ribbons, which initially emerged from twisted ribbons. Notably, the primary assemblies of these peptides exhibited opposite chirality: nanofibers formed by Ac-KI₃-CONH₂ displayed left-handed chirality, whereas those formed by Ac-RI₃-CONH₂ exhibited right-handed chirality. This reversal in torsional direction was primarily attributed to the different abilities of K and R to form hydrogen bonds with water. In contrast, Ac-HI₃-CONH₂ formed narrower twisted ribbons with a significantly reduced width of approximately 30 nm, which was attributed to the strong steric hindrance caused by the imidazole rings. The multilayer height of these ribbons was mainly due to the unique structure of the imidazole rings, which can function as both hydrogen bond donors and acceptors, thereby promoting aggregate growth in the vertical direction. ConclusionThe final morphology of the self-assemblies resulted from a delicate balance of various non-covalent interactions. By altering the types of hydrophilic amino acid residues in Bola-like short peptides, the relative strength of non-covalent interactions that drive assembly formation can be effectively regulated, allowing precise control over the morphology and chirality of the assemblies. This study provides a simple and effective approach for constructing diverse self-assemblies and lays a theoretical foundation for the development of functional biomaterials.

Electroencephalogram (EEG) is a non-invasive, high temporal-resolution technique for monitoring brain activity. However, affected by the volume conduction effect, EEG has a low spatial resolution and is difficult to locate brain neuronal activity precisely. The surface Laplacian (SL) technique obtains the Laplacian EEG (LEEG) by estimating the second-order spatial derivative of the scalp potential. LEEG can reflect the radial current activity under the scalp, with positive values indicating current flow from the brain to the scalp (“source”) and negative values indicating current flow from the scalp to the brain (“sink”). It attenuates signals from volume conduction, effectively improving the spatial resolution of EEG, and is expected to contribute to breakthroughs in neural engineering. This paper provides a systematic overview of the principles and development of SL technology. Currently, there are two implementation paths for SL technology: current source density algorithms (CSD) and concentric ring electrodes (CRE). CSD performs the Laplace transform of the EEG signals acquired by conventional disc electrodes to indirectly estimate the LEEG. It can be mainly classified into local methods, global methods, and realistic Laplacian methods. The global method is the most commonly used approach in CSD, which can achieve more accurate estimation compared with the local method, and it does not require additional imaging equipment compared with the realistic Laplacian method. CRE employs new concentric ring electrodes instead of the traditional disc electrodes, and measures the LEEG directly by differential acquisition of the multi-ring signals. Depending on the structure, it can be divided into bipolar CRE, quasi-bipolar CRE, tripolar CRE, and multi-pole CRE. The tripolar CRE is widely used due to its optimal detection performance. While ensuring the quality of signal acquisition, the complexity of its preamplifier is relatively acceptable. Here, this paper introduces the study of the SL technique in resting rhythms, visual-related potentials, movement-related potentials, and sensorimotor rhythms. These studies demonstrate that SL technology can improve signal quality and enhance signal characteristics, confirming its potential applications in neuroscientific research, disease diagnosis, visual pathway detection, and brain-computer interfaces. CSD is frequently utilized in applications such as neuroscientific research and disease detection, where high-precision estimation of LEEG is required. And CRE tends to be used in brain-computer interfaces, that have stringent requirements for real-time data processing. Finally, this paper summarizes the strengths and weaknesses of SL technology and envisages its future development. SL technology boasts advantages such as reference independence, high spatial resolution, high temporal resolution, enhanced source connectivity analysis, and noise suppression. However, it also has shortcomings that can be further improved. Theoretically, simulation experiments should be conducted to investigate the theoretical characteristics of SL technology. For CSD methods, the algorithm needs to be optimized to improve the precision of LEEG estimation, reduce dependence on the number of channels, and decrease computational complexity and time consumption. For CRE methods, the electrodes need to be designed with appropriate structures and sizes, and the low-noise, high common-mode rejection ratio preamplifier should be developed. We hope that this paper can promote the in-depth research and wide application of SL technology.

ObjectiveTo investigate the effect of folic acid-modified crebanine polyethylene glycol-polylactic acid hydroxyacetic acid copolymer（PEG-PLGA） nanoparticles（FA-Cre@PEG-PLGA NPs， hereinafter referred to as NPs） combined with ultrasonic irradiation on subcutaneous tumor of liver cancer in Kunming（KM） mice. MethodsEighty-four healthy male KM mice were utilized to establish a subcutaneous tumor model of mouse hepatocellular carcinoma with H22 cells， then mice were randomly divided into model group， placebo group， hydroxycamptothecin group（8 mg∙kg^-1）， low， medium and high dose crebanine raw material groups（2， 2.5， 3 mg∙kg^-1， hereinafter referred to as the low， medium and high dose crebanine groups， respectively）， low， medium and high dose NPs groups（2， 2.5， 3 mg∙kg^-1）， and low， medium and high dose NPs combined with ultrasonic irradiation groups（2， 2.5， 3 mg∙kg^-1， hereinafter referred to as the low， medium and high dose combination groups， respectively）. The corresponding doses of drugs were administered via tail vein injection， the model group received no treatment， while the placebo group was injected with an equivalent amount of normal saline. Dosing was conducted for a total of 10 times on alternate days. The body mass of the mice was monitored， and parameters such as body mass change rate， thymus index， spleen index， tumor volume， tumor weight， relative tumor growth rate（T/C）， and tumor inhibition rate（TGI） were calculated. Pathological changes in liver and kidney tissues as well as the tumor were observed by hematoxylin-eosin（HE） staining. Additionally， the levels of aspartate aminotransferase（AST）， alanine aminotransferase（ALT）， blood urea nitrogen（BUN） and creatinine（CREA） in serum of mice were detected by biochemical method. Furthermore， the effect of ultrasound on the distribution of NPs in subcutaneous tumors of mouse hepatocellular carcinoma was observed by in vivo imaging technique. ResultsAmong different treatment methods， the combination of NPs and ultrasound irradiation had the best therapeutic effect. Compared with the model group， the body mass growth rates of mice in the medium and high combination groups decreased， while the thymus index and spleen index increased， but there was no statistically significant difference in serum AST， ALT， BUN and CREA levels， indicating that NPs combined with ultrasound irradiation had little effect on the normal physiological state of the body， oth groups had TGI>40% and T/C<60%， indicating a clear anti-tumor effect. Pathological analysis showed that compared with the NPs groups， the combination groups exhibited varying degrees of necrosis in tumor cells， accompanied by less damage to the liver and kidneys. In vivo imaging of small animals showed that compared with the high dose NPs group， the high dose combination group had stronger tumor targeting ability（P<0.01）. ConclusionNPs combined with ultrasonic irradiation can not only effectively targeted the drug to the tumor site， inhibit the subcutaneous tumor growth of mouse liver cancer， but also decrease damage to liver and kidney tissues.

OBJECTIVE To investigate the targeting effect of folic acid-modified crebanine nanoparticles （FA-Cre@PEG- PLGA NPs， hereinafter referred to as “NPs”） combined with ultrasound irradiation on M109 cells in vitro and in vivo after administration， and explore the anti-tumor mechanism. METHODS CCK-8 assay was used to detect the inhibitory effect of NPs combined with ultrasound irradiation on the proliferation of M109 cells， and the best ultrasound time was selected. Using human lung cancer A549 cells as a control， the targeting of NPs combined with ultrasound irradiation to M109 cells was evaluated by free folic acid blocking assay and cell uptake assay. The effects of NPs combined with ultrasound irradiation on the migration， invasion， apoptosis， cell cycle and reactive oxygen species （ROS） levels of M109 cells were detected by cell scratch test， Transwell chamber test and flow cytometry at 1 h after 958401536@qq.com administration； the changes of mitochondrial membrane potential （MMP） were observed by fluorescence inverted microscope. A mouse subcutaneous tumor model of M109 cells was constructed， and the in vivo tumor targeting of NPs combined with ultrasound irradiation was investigated by small animal in vivo imaging technology. RESULTS NPs combined with ultrasound irradiation could significantly inhibit the proliferation of M109 cells， and the optimal ultrasound time was 1 h after administration. The free folic acid could antagonize the inhibitory effect of NPs on the proliferation of M109 cells， and combined with ultrasound irradiation could partially reverse this antagonism. Compared with A549 cells， the uptake rate of NPs in M109 cells was significantly higher （P＜0.01）， and ultrasound irradiation could promote cellular uptake. NPs combined with ultrasound irradiation could inhibit the migration and invasion of M109 cells and block the cell cycle in the G0/G1 and G2/M phases. Compared with control group， the apoptosis rate of M109 cells and ROS level were increased significantly （P＜0.01）， while the MMP decreased significantly （P＜0.01） in the different concentration （100， 200， 300 μg/mL） groups of M109 cells. Compared with the mice in non-ultrasound group， the fluorescence intensity and tumor-targeting index of the tumor site in the 0 h ultrasound group were significantly enhanced （P＜0.05 or P＜0.01）. CONCLUSIONS NPs combined with ultrasound irradiation have a strong targeting effect on M109 cells in vitro and in vivo， the anti-tumor mechanism includes inhibiting cell migration and invasion， blocking cell cycle， and inducing apoptosis.

Aim To examine the neuroprotective im-pacts of total saponins from Trillium tschonoskii maxim(TST)on cerebral ischemia-reperfusion injury(CIRI)in rats and delve into the mechanisms of ferroptosis.Methods The CIRI model was prepared by dividing male SD rats into the model group,TST(0.1 g·kg-1)group,Donepezil hydrochloride(0.45 mg·kg-1)group,and sham group.The cognitive functions of rats in each group were assessed through the Morris water maze test,the changes in neurological function were evaluated using the Zea-Longa method,the infarct area was observed via TTC staining,and the pathologi-cal alterations in brain tissue were analysed using HE and Nissl staining.To further investigate the underly-ing mechanism,the mitochondrial structural changes were examined using transmission electron microscopy,and the levels of GSH-PX,MDA,and SOD were ana-lyzed.Additionally,the expressions of GPX4 and Nrf2 proteins were evaluated through immunohistochemistry and immunofluorescence.Furthermore,the protein lev-els of Keap1/Nrf2/HO-1 and Nrf2/SLC7A11/GPX4 pathways in rats were examined using Western blot-ting.Results The rats in the model group displayed diminished learning and memory capabilities in com-parison to those in the sham group,as well as a signifi-cantly increased cerebral infarction area and higher neurological function scores(P＜0.01),significantly increased cerebral infarct area,disordered and loosely arranged neurons,and reduced Nissl bodies.Addition-ally,mitochondria showed typical signs of ferroptosis.Changes related to ferroptosis included decreased activ-ities of SOD and GSH-PX(P＜0.01)and increased MDA levels(P＜0.01).The expression of GPX4 and Nrf2-positive cells was significantly reduced,along with decreased fluorescence intensity of GPX4.Further-more,the protein expression of Keap1,Nrf2,HO-1,GPX4,SLC7A11 in the hippocampus decreased(P＜0.05,P＜0.01).Following the administration of TST,these effects showed improvement.Conclusions TST has neuroprotective effects,enhancing learning and memory abilities while reducing oxidative stress levels.The mechanism may involve the inhibition of ferroptosis through the Keap-1/Nrf2/HO-1 and Nrf2/SLC7 A11/GPX4 pathways.

Aim To investigate the preventive and therapeutic effects of the mfat-1 gene therapy on exper-imental autoimmune encephalomyelitis in mice.Meth-ods mfat-1 gene therapy was used to render the host endogenous capability of producing ω-3 PUFAs,con-comitantly reduce the levels of ω-6 PUFAs,and change the proportion of ω-3/ω-6 PUFAs.Then,the levels of PUFAs in blood were analyzed by gas chromatography.The neurological deficits in mice were evaluated by neurological dysfunction score.HE staining and LFB staining of mouse spinal cord slices were used to ob-serve central nervous system inflammation infiltration and demyelinating lesions.Flow cytometry microsphere microarray technology was used to detect the content of cytokines in serum.Results The mfat-1 gene therapy could significantly raise the proportion of ω-3/ω-6 PU-FAs(P＜0.05),markedly delay the incubation period and peak period and reduce neurological dysfunction scores(P＜0.05),and improve inflammation and de-myelination of spinal cords(P＜0.05).It could also greatly increase the levels of IL-2,IFN-γ,IL-4 and IL-17 in serum(P＜0.05).Conclusion The pro-portion of ω-3/ω-6 PUFAs in blood circulation en-hanced by mfat-1 gene therapy can effectively prevent and treat experimental autoimmune encephalomyelitis in mice.

Objective To investigate the risk factors for delayed union of extra-articular fractures of the middle and lower third of the tibia treated by locking plate.Methods Total of 135 patients of extra-articular fractures of the middle and lower third of the tibia from January 2013 to December 2018 were retrospectively analyzed,including 85 males and 50 females,ranged from 19 to 80 years old.All cases were treated with locking plates.The patients were divided into union group and delayed union group ac-cording to the condition of fracture union.The risk factors of delayed healing were determined by univariate analysis of 14 factors that might affect fracture healing first,then the factors with significance were analyzed by binary Logistic regression.Results There were 13 patients of delayed union,and the rate of delayed union was 9.63％.Univariate analysis showed that delayed union was associated with age,smoking,reduction method,anemia and time of preoperative preparation.Regression analysis showed thatage[OR=0.849,95％CI(0.755,0.954),P=0.006],smoking[OR=0.020,95％CI(0.002,0.193),P=0.001],reduction method[OR=23.924,95％CI(2.210,258.943),P=0.009],anemia[OR=0.016,95％CI(0.001,0.289),P=0.005]were the con-tributory factors for delayed union.Conclusion Young age,smoking,closed reduction and anemia are the risk factors for de-layed union of extra-articular fractures of the middle and lower third of the tibia treated by locking plate.

Objective To investigate the feasibility of translocation of pedicled buccal fat pad in the treatment of the temporomandibular joint ankylosis(TMJA)by measuring the diameter of buccal fat pad and related anatomical structures of the transverse blood vessels,nerves and temporomandibular joint.Methods A total of 40 adult head and neck specimens were randomly divided into group A and group B,with 20 cases in each group.The morphology of the buccal fat pad in group A was observed,and its size and compression diameter through blood vessels and nerves were measured.The anatomical structures of the temporomandibular joint in group B were observed and measured.Results The volume of buccal fat pad in group A was(10.10±1.10)mL on the left side and(9.70±1.50)mL on the right side.The longitudinal axis length of buccal fat pad was(28.18±1.35)mm on the left side and(29.47±1.12)mm on the right side;Transverse axis length of buccal fat pad was(18.56±1.67)mm on the left side and(18.97±1.73)mm on the right side;There are facial artery,facial vein,maxillary artery branch,facial nerve buccal branch and so on through the buccal fat pad.In group B,the sagittal section of the temporomandibular joint disc presented S-type in 15 cases(75.0%),L-type in 3 cases(15.0%),and transitional type in 2 cases(10.0%).Anterior and posterior diameter of the articular disc was(14.42±1.94)mm on the left side and(15.34±1.37)mm on the right side;inside and outside diameter of the articular disc was(20.18±1.77)mm on the left side and(19.57±1.32)mm on the right side.Branches of maxillary artery and superficial temporal artery were respectively distributed within and outside the joint.Conclusion The pedicled buccal fat pad has a constant anatomical position,abundant blood supply,strong tissue repair,anti-infection ability and"buffer pad"function,which can reduce the formation of scar after surgery for TMJA,reduce the postoperative recurrence rate,and contribute to the recovery of joint function after surgery.

To investigate the existence of tick-borne pathogens infection of rodents at the border of China and the Demo-cratic People's Republic of Korea(DPRK).PCR was used to detect the spotted fever group rickettsiae(SFGR)ompA gene,Ehrlichia chaffeensis(Ec)and Anaplasma phagocytophilum(Ap)16S rRNA,Candidatus Neoehrlichia mikurensis(CNm)groEL gene,Bartonella(Ba)rpoB gene,and Francisella tularensis(Ft)fopA gene in rodents samples collected from Ji'an of Jilin province and Kuandian of Liaoning Province.The positivity rates of 132 wild rats spleen samples,SFGR,Ec,Ap,CNm,Ba,and Ft were 9.85％,12.88％,5.30％,3.79％,51.52％,and 6.06％,respectively,with statistical differences in in-fection rates(x2=149.236,P=0.000).The infection rate of Ba was the highest in wild rats in this area.There was no signifi-cant difference in the infection rate of SFGR,Ec,Ap,CNm,and Ft among different rats species,but there were significant differences in the infection rate of Ba(x2=13.36,P=0.010).The infection rate of Apodemus agrarius was the highest.A-mong 132 wild rats specimens,the coinfection rate of the two pathogens was 15.9％(21/132),with Ba as the main species(15/132),and two cases of coinfection with three pathogens were detected.The infection of six tick-borne pathogens is common in wild rats at the China/DPRK border.Co-infection of two or three pathogens indicates a risk of multiple tick-borne pathogens and mixed natural foci of multiple tick-borne infec-tious diseases.

Objective:To explore the levels of regulatory T cells(Tregs)and cytokines IL-35,TGF-β and IL-10 in peripheral blood of hemophilia A(HA)patients with F Ⅷ inhibitor and their clinical significance.Methods:43 HA patients admitted to the Hematology Department of the Affiliated Hospital of North China University of Science and Technology from October 2019 to December 2020 were selected,including 6 cases with F Ⅷ inhibitor and 37 cases without FⅧ inhibitor.In addition,20 healthy males who underwent physical examinations were selected as healthy controls.Flow cytometry was used to detect the levels of CD4+CD25+CD127-Tregs in peripheral blood of the HA patients and healthy controls,and ELISA assay was used to detect the expression levels of IL-35,TGF-β and IL-10 in serum,and their differences between different groups were compared.Results:Compared with the healthy control group,the level of Tregs in HA patients was decreased,and the level of Tregs in the FⅧ inhibitor positive group was the lowest,the difference was statistically significant(P＜0.05).There was no significant difference in the expression level of Tregs in HA patients of different severity levels.The serum IL-35,TGF-β,and IL-10 levels in both FⅧ inhibitor negative and positive groups were significantly lower than those in healthy control group,and those in FⅧ inhibitor positive group were significantly lower than those in FⅧ inhibitor negative group(all P＜0.05).Conclusion:The decrease of Tregs,IL-35,TGF-β,and IL-10 levels in HA patients may be related to the formation of FⅧ inhibitors.