Objective To study the stress change characteristics of the cervical disc after removing different ranges of the uncinate process by establishing a three⁃dimensional finite element model of the C

Structural maintenance of chromosomes (SMC), including cohesin, condensin and the SMC5/6 complex, are protein complexes which maintain the higher structure and dynamic stability of chromatin. Such circular complexes, with similar structures, play pivotal roles in chromatid cohesion, chromosomal condensation, DNA replication and repair, as well as gene transcription. Despite extensive research on the functions of the SMCs, our understanding of the SMC5/6 complex has remained limited compared with the other two complexes. This article has reviewed the architecture and crucial physiological roles of the SMCs, and explored the associated phenotypes resulting from mutations of the SMC components such as Cornelia de Lange syndrome (CdLS) and microcephaly, with an aim to provide insights into their functions in eukaryotic cells and implications for human diseases.

Intramedullary needle(IMN)has the advantages of high healing rate and low incidence of complications in treatment of tibial fracture,and has become one of the most commonly used fixation methods for the treatment of tibial fracture.However,due to the patient's own factors,fracture location and fracture type,infection and surgical treatment,bone nonunion after IMN still occurs in clinic.Bone nonunion leads to the increase of medical cost and prolonged the hospitalization time of patients,which causes great pain to patients,and also brings great challenges to the treatment of orthopedic surgeons.Therefore,this paper reviews the influencing factors of bone nonunion after IMN for tibial fracture,in order to provide reference for clinical treatment.

Objective To monitor the susceptibility of clinical isolates to antimicrobial agents in tertiary hospitals in major regions of China in 2022.Methods Clinical isolates from 58 hospitals in China were tested for antimicrobial susceptibility using a unified protocol based on disc diffusion method or automated testing systems.Results were interpreted using the 2022 Clinical &Laboratory Standards Institute(CLSI)breakpoints.Results A total of 318 013 clinical isolates were collected from January 1,2022 to December 31,2022,of which 29.5％were gram-positive and 70.5％were gram-negative.The prevalence of methicillin-resistant strains in Staphylococcus aureus,Staphylococcus epidermidis and other coagulase-negative Staphylococcus species(excluding Staphylococcus pseudintermedius and Staphylococcus schleiferi)was 28.3％,76.7％and 77.9％,respectively.Overall,94.0％of MRSA strains were susceptible to trimethoprim-sulfamethoxazole and 90.8％of MRSE strains were susceptible to rifampicin.No vancomycin-resistant strains were found.Enterococcus faecalis showed significantly lower resistance rates to most antimicrobial agents tested than Enterococcus faecium.A few vancomycin-resistant strains were identified in both E.faecalis and E.faecium.The prevalence of penicillin-susceptible Streptococcus pneumoniae was 94.2％in the isolates from children and 95.7％in the isolates from adults.The resistance rate to carbapenems was lower than 13.1％in most Enterobacterales species except for Klebsiella,21.7％-23.1％of which were resistant to carbapenems.Most Enterobacterales isolates were highly susceptible to tigecycline,colistin and polymyxin B,with resistance rates ranging from 0.1％to 13.3％.The prevalence of meropenem-resistant strains decreased from 23.5％in 2019 to 18.0％in 2022 in Pseudomonas aeruginosa,and decreased from 79.0％in 2019 to 72.5％in 2022 in Acinetobacter baumannii.Conclusions The resistance of clinical isolates to the commonly used antimicrobial agents is still increasing in tertiary hospitals.However,the prevalence of important carbapenem-resistant organisms such as carbapenem-resistant K.pneumoniae,P.aeruginosa,and A.baumannii showed a downward trend in recent years.This finding suggests that the strategy of combining antimicrobial resistance surveillance with multidisciplinary concerted action works well in curbing the spread of resistant bacteria.

Inertial microfluidics,as a microfluidic technology with the ability to precisely manipulate particles and cells with high throughput,has attracted widespread attention.However,challenges remain in achieving particle focusing with insensitivity to flow rates in large-scale channels,mainly due to the instability of secondary flows within the inertial microfluidic chip.This study developed a microstructure-assisted ultra-low aspect ratio spiral microchannel,which utilized the stability and acceleration of secondary flows to achieve inertial particle focusing.The research results demonstrated successful particle focusing within a 1 mm-wide spiral channel chip,for different diameter sizes(7.3 μm and 15.5 μm),within a wide range of flow rates(0.5-3 mL/min).The focusing efficiencies for these particles were measured to be above 94%and 99%,respectively.Additionally,it was observed that the particle focusing position was approximately 100 μm away from the channel walls,significantly larger than other inertial focusing chips.Consequently,by incorporating ordered microstructures within the spiral channel chip,the stability and enhancement of secondary flows were achieved,resulting in flow rate and particle size-insensitive inertial focusing.Compared to traditional methods of inertial focusing,this design had advantages of not requiring additional sheath flow operations,and boasted high throughput and ease of manufacturing.This innovative structure opened up vast prospects for the development of portable inertial microfluidic chips,and could be used in the fields such as cell analysis and detection,flow cytometry,and online sample processing.

Objective To evaluate the in vitro effect of combinations of 5 β-lactam antibiotics with different β-lac-tamase inhibitors on the activity of multidrug-resistant Mycobacterium tuberculosis(MDR-TB),and identify the most effective combination of β-lactam antibiotics and β-lactamase inhibitors against MDR-TB.Methods MDR-TB strains collected in Henan Province Antimicrobial Resistance Surveillance Project in 2021 were selected.The mini-mum inhibitory concentrations(MIC)of 5 β-lactam antibiotics or combinations with different β-lactamase inhibitors on clinically isolated MDR-TB strains were measured by MIC detection method,and the blaC mutation of the strains was analyzed by polymerase chain reaction(PCR)and DNA sequencing.Results A total of 105 strains of MDR-TB were included in the analysis.MIC detection results showed that doripenem had the highest antibacterial activity against MDR-TB,with a MIC50 of 16 μg/mL.MIC values of most β-lactam antibiotics decreased significantly after combined with β-lactamase inhibitors.A total of 13.33％(n=14)strains had mutations in blaC gene,mainly 3 nu-cleotide substitution mutations,namely AGT333AGG,AAC638ACC and ATC786ATT.BlaC proteins Ser111 Arg and Asn213Thr enhanced the synergistic effect of clavulanic acid/sulbactam and meropenem on MDR-TB compared with synonymous single-nucleotide mutation.Conclusion The combination of doripenem and sulbactam has the strongest antibacterial activity against MDR-TB.Substitution mutations of BlaC protein Ser111 Arg and Asn213Thr enhances the sensitivity of MDR-TB to meropenem through the synergy with clavulanic acid/sulbactam.

OBJECTIVE: To observe the effects of acupuncture at "Kongzui" (LU 6) and "Yuji" (LU 10) on the latent period of inducing asthma, pulmonary function and the expression of endothelin-1 (ET-1) and metallothionein-2 (MT-2) in asthma rats, and to explore the possible mechanism of acupuncture in alleviating airway smooth muscle spasm and improving the acute attack of asthma. METHODS: A total of 40 male SD rats of SPF-grade were randomly divided into a normal group, a model group, a medication group and an acupuncture group, 10 rats in each group. Except for the normal group, ovalbumin sensitization method was used to establish the asthma model in the other 3 groups. Salbutamol nebulization was adopted in the medication group, while acupuncture was applied at bilateral "Kongzui" (LU 6) and "Yuji" (LU 10) in the acupuncture group. The intervention was given once a day for 14 days in the two groups. The latent period of inducing asthma and pulmonary function were observed, the levels of ET-1 and tumor necrosis factor (TNF)-α in serum and bronchoalveolar lavage fluid (BALF) were detected by ELISA method, the morphology of the airway was observed by Masson staining, the ultrastructure of the airway smooth muscle was observed by transmission electron microscopy, the mRNA and protein expression of ET-1 and MT-2 in lung tissue was detected by real-time PCR and Western blot methods. RESULTS: Compared with the normal group, in the model group, the latent period of inducing asthma was shortened (P<0.01); the airway resistance (RL) was increased while the dynamic compliance (Cdyn) was decreased (P<0.01, P<0.05); the levels of ET-1 and TNF-α in serum and BALF were increased (P<0.01); collagen fibers and collagen depositions were found around the bronchi, airway smooth muscle was thickened, the cell damage was severe and mitochondria were swollen; the mRNA and protein expression of ET-1 was increased while the mRNA and protein expression of MT-2 was decreased (P<0.01). Compared with the model group, in the acupuncture group, the latent period of inducing asthma was prolonged (P<0.05), the RL was decreased while the Cdyn was increased (P<0.01, P<0.05). Compared with the model group, in the medication group and the acupuncture group, the levels of ET-1 and TNF-α in serum and BALF were decreased (P<0.01, P<0.05); collagen fibers and collagen depositions around the bronchi were reduced, the thickened airway smooth muscle was lightened, the cell damage was improved; the mRNA and protein expression of ET-1 was decreased while the mRNA and protein expression of MT-2 was increased (P<0.01). Compared with the medication group, the mRNA expression of MT-2 was increased in the acupuncture group (P<0.05). CONCLUSION Acupuncture at "Kongzui" (LU 6) and "Yuji" (LU 10) can improve the pulmonary function and alleviate the airway smooth muscle spasm in rats with asthma. Its mechanism may be related to the down-regulation of ET-1 expression and up-regulation of MT-2 expression.
Rats ; Male ; Animals ; Tumor Necrosis Factor-alpha/metabolism* ; Rats, Sprague-Dawley ; Lung ; Asthma/metabolism* ; Acupuncture Therapy ; Spasm ; RNA, Messenger/metabolism*

Although the development of COVID-19 vaccines has been a remarkable success, the heterogeneous individual antibody generation and decline over time are unknown and still hard to predict. In this study, blood samples were collected from 163 participants who next received two doses of an inactivated COVID-19 vaccine (CoronaVac®) at a 28-day interval. Using TMT-based proteomics, we identified 1,715 serum and 7,342 peripheral blood mononuclear cells (PBMCs) proteins. We proposed two sets of potential biomarkers (seven from serum, five from PBMCs) at baseline using machine learning, and predicted the individual seropositivity 57 days after vaccination (AUC = 0.87). Based on the four PBMC's potential biomarkers, we predicted the antibody persistence until 180 days after vaccination (AUC = 0.79). Our data highlighted characteristic hematological host responses, including altered lymphocyte migration regulation, neutrophil degranulation, and humoral immune response. This study proposed potential blood-derived protein biomarkers before vaccination for predicting heterogeneous antibody generation and decline after COVID-19 vaccination, shedding light on immunization mechanisms and individual booster shot planning.
Humans ; COVID-19 Vaccines ; Leukocytes, Mononuclear ; Proteomics ; COVID-19/prevention & control* ; Vaccination ; Antibodies ; Antibodies, Viral ; Antibodies, Neutralizing