BACKGROUND:The pelvis has abundant trabecular bone content,but the ability of conventional sacroiliac percutaneous fixation to control trabecular bone is limited,leading to fixation failure.Therefore,the development of devices that can more effectively control trabecular bone tension is of significant importance.OBJECTIVE:The mechanical properties of a novel sacroiliac tension screw were investigated using biomechanical testing and numerical modeling analysis,along with an assessment of the reliability of the pull-out force numerical model.METHODS:A mechanical model was established based on the working principle of the novel sacroiliac tension screw.Numerical methods were employed to analyze its pull-out performance,validated through mechanical testing with polyurethane material to assess the reliability of the pull-out force numerical model.Using pelvic specimens,the mechanical effectiveness of the novel sacroiliac tension screw in repairing sacroiliac joint injuries was analyzed under normal standing posture,along with an evaluation of the load stiffness of different pelvic models in the standing position.RESULTS AND CONCLUSION:(1)The average error between the computed values of the numerical model and the measured values was 13.19％,indicating a certain level of validity for the numerical model.(2)The damage to the polyurethane material after the extraction of the screw was less pronounced in the novel screw group.(3)The average effective holding displacement for the novel screw was approximately(9.24±0.27)mm,significantly greater than the average displacement of(1.71±0.57)mm observed with the lag screws.However,the maximum resistance to pullout for the lag screws was significantly higher than that for the novel screws.(4)The novel screw effectively repaired sacroiliac joint injuries.(5)The stiffness after repair of sacroiliac joint injuries was equivalent when using a single novel screw compared to using two lag screws.(6)These results prove that the theoretical model for the maximum resistance to pullout of the screws established in this study has a certain level of validity and can guide the design of them with improved mechanical performance.The novel sacroiliac spiral blade screw can effectively hold trabecular bone and has practical clinical utility.

Objective:To study the risk factors and the molecular epidemiology characteristics for Carbapenem-resistant Enterobacteriaceae(CRE) colonization in neonatal inpatients in Shenzhen region, China, which provide reference for the prevention and control of clinical CRE infection.Methods:This study is a prospective case-control study.Anal samples from inpatients between January 2023 and December 2023 at Longgang Maternity and Child Institute of Shantou University Medical College and Shenzhen Children's Hospital were collected for screening CRE strain. Drug susceptibility test, modified Carbapenem Inactivation Method (mCIM) test, drug resistance-related gene sequencing and multilocus sequence typing (MLST) were performed for isolated CRE strains.Meanwhile, the clinical data were collected for analyzing the risk factors of CRE intestinal colonization by multivariate regression analysis.Results:A total of 1 517 patients were screened, 26 CRE(1.7%, 26/1 517) were identified which including 14 Escherichia coli(53.8%, 14/26), 11 Klebsiella pneumoniae(42.3%, 11/26), 1 Enterobacter cloacae(3.9%, 1/26). The predominant carbapenemase gene was New Delhi Metallo(NDM) (92.4%, 24/26), followed by Imipenem (IMP) (3.8%, 1/26) and Guiana extended spectrum gene (GES) (3.8%, 1/26).Among the carried NDM resistance genes, New Delhi Metallo 5 (NDM5) was the main one, accounting for 84.6% (22/26).The MLST typing of Escherichia coli was mainly Sequence Type 48 (ST48) (6/14), while that of Klebsiella pneumoniae was mainly Sequence Type 35 (ST35) (10/11). All CRE isolates were resistant to penicillin, penicillinase inhibitors, cephalosporins, ertapenem and imipenem.The resistance rates of Escherichia coli to amikacin, levofloxacin was 1/14, 4/14, respectively. All isolates of Klebsiella pneumoniae were sensitive to amikacin, and the resistance rate to levofloxacin is 1/11. Risk factors for CRE colonization include the older age, length of hospital stay, tracheal intubation, invasive respiration, lumbar puncture, Apgar <7 score, and exposure to antibiotics.Conclusions:NDM5 is the predominant resistant gene in CRE isolated from neonatal patients feces in Shenzhen region.It is necessary to strengthen the screening of CRE colonization in neonate for prevention and control of CRE infection.

The xylitol dehydrogenase(XDH)is a crucial enzyme involved in the xylose utilization in pentose-catabolizing yeasts and fungi.In addition to producing xylulose,XDH can also be employed to develop a biosensor for monitoring xylitol concentration.In this study,the gene encoding the thermophilic fungus Talaromyces emersonii XDH(TeXDH)was heterologously expressed in Escherichia coli BL21(DE3)at 16 ℃ in the soluble form.Recombinant TeXDH with high purity was purified by using a Ni-NTA affinity column.Size-exclusion chromatography and SDS-PAGE analysis demonstrated that the puri-fied recombinant TeXDH exists as a native trimer with a molecular mass of approximately 116 kD,and is composed of three identical subunits,each with a molecular weight of around 39 kD.The TeXDH strictly preferred NAD+as a coenzyme to NADP+.The optimal temperature and pH of the TeXDH were 40 ℃and 10.0,respectively.After EDTA treatment,the enzyme activity of TeXDH decreased to 43.26％of the initial enzyme activity,while the divalent metal ions Mg2+or Ca2+could recover the enzyme activity of TeXDH,reaching 103.32％and 110.69％of the initial enzyme activity,respectively,making them the optimal divalent metal ion cofactors for TeXDH enzyme.However,the divalent metal ions of Mn2+,Ni2+,Cu2+,Zn2+,Co2+,and Cd2+significantly inhibited the activity of TeXDH.ICP-MS and molecular doc-king studies revealed that 1 mol/L of TeXDH bound 2 mol/L Zn2+ions and 1 mol/L Mg2+ion.Further-more,TeXDH exhibited a high specificity for xylitol,laying the foundation for the development of future xylitol biosensors.

OBJECTIVES: To characterize fine particulate matter (PM _2.5)-bound polycyclic aromatic hydrocarbons (PAHs) emitted from different cooking fumes and their exposure routes and assess their health-associated impact to provide a reference for health risk prevention from PAH exposure across different age and sex groups. METHODS: Sixteen PM _2.5-bound PAHs emitted from 11 cooking styles were analyzed using GC-MS/MS. The health hazards of these PAHs in the Handan City population (stratified by age and sex) were predicted using the incremental lifetime cancer risk ( ILCR) model. The respiratory deposition doses ( RDDs) of the PAHs in children and adults were calculated using the PM _2.5 deposition rates in the upper airway, tracheobronchial, and alveolar regions. RESULTS: The total concentrations of PM _2.5-bound PAHs ranged from 61.10 to 403.80 ng/m ³. Regardless of cooking styles, the ILCR _total values for adults (1.23 × 10 ^-6 to 3.70 × 10 ^-6) and older adults (1.28 × 10 ^-6 to 3.88 × 10 ^-6) exceeded the acceptable limit of 1.00 × 10 ^-6. With increasing age, the ILCR _total value first declined and then increased, varying substantially among the population groups. Cancer risk exhibited particularly high sensitivity to short exposure to barbecue-derived PAHs under equivalent body weights. Furthermore, barbecue, Sichuan and Hunan cuisine, Chinese cuisine, and Chinese fast food were associated with higher RDDs for both adults and children. CONCLUSION ILCR _total values exceeded the acceptable limit for both females and males of adults, with all cooking styles showing a potentially high cancer risk. Our findings serve as an important reference for refining regulatory strategies related to catering emissions and mitigating health risks associated with cooking styles.
Humans ; Polycyclic Aromatic Hydrocarbons/analysis* ; Cooking/methods* ; Male ; Female ; Particulate Matter/analysis* ; Adult ; Child ; Middle Aged ; Air Pollutants/analysis* ; Adolescent ; Air Pollution, Indoor/analysis* ; Young Adult ; Child, Preschool ; Aged ; China ; Inhalation Exposure ; Age Factors ; Sex Factors ; Cities ; Infant

Objective To investigate the distribution and antimicrobial resistance profiles of clinically isolated Haemophilus influenzae and Moraxella catarrhalis in hospitals across China from 2015 to 2021,and provide evidence for rational use of antimicrobial agents.Methods Data of H.influenzae and M.catarrhalis strains isolated from 2015 to 2021 in CHINET program were collected for analysis,and antimicrobial susceptibility testing was performed by disc diffusion method or automated systems according to the uniform protocol of CHINET.The results were interpreted according to the CLSI breakpoints in 2022.Beta-lactamases was detected by using nitrocefin disk.Results From 2015 to 2021,a total of 43 642 strains of Haemophilus species were isolated,accounting for 2.91％of the total clinical isolates and 4.07％of Gram-negative bacteria in CHINET program.Among the 40 437 strains of H.influenzae,66.89％were isolated from children and 33.11％were isolated from adults.More than 90％of the H.influenzae strains were isolated from respiratory tract specimens.The prevalence of β-lactamase was 53.79％in H.influenzae strains.The H.influenzae strains isolated from children showed higher resistance rate than the strains isolated from adults.Overall,779 strains of H.influenzae did not produce β-lactamase but were resistant to ampicillin(BLNAR).Beta-lactamase-producing strains showed significantly higher resistance rates to these antimicrobial agents than the β-lactamase-nonproducing strains.Of the 16 191 M.catarrhalis strains,80.06％were isolated from children and 19.94％isolated from adults.M.catarrhalis strains were mostly susceptible to both amoxicillin-clavulanic acid and cefuroxime,evidenced by resistance rate lower than 2.0％.Conclusions The emergence of antibiotic-resistant H.influenzae due to β-lactamase production poses a challenge for clinical anti-infective treatment.Therefore,it is very important to implement antibiotic resistance surveillance for H.influenzae and guide rational antibiotic use.All local clinical microbiology laboratories should actively improve antibiotic susceptibility testing and strengthen antibiotic resistance surveillance for H.influenzae.

The xylitol dehydrogenase(XDH)is a crucial enzyme involved in the xylose utilization in pentose-catabolizing yeasts and fungi.In addition to producing xylulose,XDH can also be employed to develop a biosensor for monitoring xylitol concentration.In this study,the gene encoding the thermophilic fungus Talaromyces emersonii XDH(TeXDH)was heterologously expressed in Escherichia coli BL21(DE3)at 16 ℃ in the soluble form.Recombinant TeXDH with high purity was purified by using a Ni-NTA affinity column.Size-exclusion chromatography and SDS-PAGE analysis demonstrated that the puri-fied recombinant TeXDH exists as a native trimer with a molecular mass of approximately 116 kD,and is composed of three identical subunits,each with a molecular weight of around 39 kD.The TeXDH strictly preferred NAD+as a coenzyme to NADP+.The optimal temperature and pH of the TeXDH were 40 ℃and 10.0,respectively.After EDTA treatment,the enzyme activity of TeXDH decreased to 43.26％of the initial enzyme activity,while the divalent metal ions Mg2+or Ca2+could recover the enzyme activity of TeXDH,reaching 103.32％and 110.69％of the initial enzyme activity,respectively,making them the optimal divalent metal ion cofactors for TeXDH enzyme.However,the divalent metal ions of Mn2+,Ni2+,Cu2+,Zn2+,Co2+,and Cd2+significantly inhibited the activity of TeXDH.ICP-MS and molecular doc-king studies revealed that 1 mol/L of TeXDH bound 2 mol/L Zn2+ions and 1 mol/L Mg2+ion.Further-more,TeXDH exhibited a high specificity for xylitol,laying the foundation for the development of future xylitol biosensors.

Group C rotavirus（RVC）is one of the important etiological agents responsible for human rotavirus gastroenteritis（RVGE）. Although its overall detection rate has shown a declining trend in recent years，sporadic outbreaks continue to be reported，highlighting its potential public health threat. RVC infections predominantly occur in preschool children，adolescents，and adults，typically presenting with mild to moderate diarrhea. While most cases are sporadic，cluster outbreaks can also occur. At present，fundamental research on RVC remains limited，particularly regarding its transmission and pathogenesis. Nevertheless，emerging evidence suggests that interspecies transmission may represent a key route of human infection. This review provides a comprehensive overview of current research on RVC-associated gastroenteritis，with a particular focus on its virological characteristics，epidemiological patterns，clinical manifestations，and preventive and control strategies. It aims to offer a theoretical foundation and practical reference for future studies and public health interventions targeting RVC.

Objective:To study the risk factors and the molecular epidemiology characteristics for Carbapenem-resistant Enterobacteriaceae(CRE) colonization in neonatal inpatients in Shenzhen region, China, which provide reference for the prevention and control of clinical CRE infection.Methods:This study is a prospective case-control study.Anal samples from inpatients between January 2023 and December 2023 at Longgang Maternity and Child Institute of Shantou University Medical College and Shenzhen Children's Hospital were collected for screening CRE strain. Drug susceptibility test, modified Carbapenem Inactivation Method (mCIM) test, drug resistance-related gene sequencing and multilocus sequence typing (MLST) were performed for isolated CRE strains.Meanwhile, the clinical data were collected for analyzing the risk factors of CRE intestinal colonization by multivariate regression analysis.Results:A total of 1 517 patients were screened, 26 CRE(1.7%, 26/1 517) were identified which including 14 Escherichia coli(53.8%, 14/26), 11 Klebsiella pneumoniae(42.3%, 11/26), 1 Enterobacter cloacae(3.9%, 1/26). The predominant carbapenemase gene was New Delhi Metallo(NDM) (92.4%, 24/26), followed by Imipenem (IMP) (3.8%, 1/26) and Guiana extended spectrum gene (GES) (3.8%, 1/26).Among the carried NDM resistance genes, New Delhi Metallo 5 (NDM5) was the main one, accounting for 84.6% (22/26).The MLST typing of Escherichia coli was mainly Sequence Type 48 (ST48) (6/14), while that of Klebsiella pneumoniae was mainly Sequence Type 35 (ST35) (10/11). All CRE isolates were resistant to penicillin, penicillinase inhibitors, cephalosporins, ertapenem and imipenem.The resistance rates of Escherichia coli to amikacin, levofloxacin was 1/14, 4/14, respectively. All isolates of Klebsiella pneumoniae were sensitive to amikacin, and the resistance rate to levofloxacin is 1/11. Risk factors for CRE colonization include the older age, length of hospital stay, tracheal intubation, invasive respiration, lumbar puncture, Apgar <7 score, and exposure to antibiotics.Conclusions:NDM5 is the predominant resistant gene in CRE isolated from neonatal patients feces in Shenzhen region.It is necessary to strengthen the screening of CRE colonization in neonate for prevention and control of CRE infection.

BACKGROUND:The pelvis has abundant trabecular bone content,but the ability of conventional sacroiliac percutaneous fixation to control trabecular bone is limited,leading to fixation failure.Therefore,the development of devices that can more effectively control trabecular bone tension is of significant importance.OBJECTIVE:The mechanical properties of a novel sacroiliac tension screw were investigated using biomechanical testing and numerical modeling analysis,along with an assessment of the reliability of the pull-out force numerical model.METHODS:A mechanical model was established based on the working principle of the novel sacroiliac tension screw.Numerical methods were employed to analyze its pull-out performance,validated through mechanical testing with polyurethane material to assess the reliability of the pull-out force numerical model.Using pelvic specimens,the mechanical effectiveness of the novel sacroiliac tension screw in repairing sacroiliac joint injuries was analyzed under normal standing posture,along with an evaluation of the load stiffness of different pelvic models in the standing position.RESULTS AND CONCLUSION:(1)The average error between the computed values of the numerical model and the measured values was 13.19％,indicating a certain level of validity for the numerical model.(2)The damage to the polyurethane material after the extraction of the screw was less pronounced in the novel screw group.(3)The average effective holding displacement for the novel screw was approximately(9.24±0.27)mm,significantly greater than the average displacement of(1.71±0.57)mm observed with the lag screws.However,the maximum resistance to pullout for the lag screws was significantly higher than that for the novel screws.(4)The novel screw effectively repaired sacroiliac joint injuries.(5)The stiffness after repair of sacroiliac joint injuries was equivalent when using a single novel screw compared to using two lag screws.(6)These results prove that the theoretical model for the maximum resistance to pullout of the screws established in this study has a certain level of validity and can guide the design of them with improved mechanical performance.The novel sacroiliac spiral blade screw can effectively hold trabecular bone and has practical clinical utility.

Objective:To design a set of simulation system for surgical operation based on virtual reality(VR)technique and intelligent scoring functions,so as to assess its clinical application effect.Methods:The Digital Imaging and Communications in Medicine(DICOM)images of typical patients were collected.Materialise Interactive Medical Image Control System(MIMICS)software was adopted to reconstruct the three-dimensional(3D)model of diseased organs.Surgical instrument models were constructed by using 3D Max software.Unity 3D software was adopted to construct simulation system for surgical operation with VR+intelligent scoring.A total of 40 surgical resident physicians,who were employed with 3 years since 2019 in The Second Affiliated Hospital of Kunming Medical University,were selected.They were divided into observation group and control group,with 20 cases in each group.The observation group used simulation system for surgical operation to conduct intelligent scoring for cholecystectomy under laparoscope,and the control group used conventional scoring for surgical operation.The scores of surgical operation and test between the two groups were compared.Results:The mean value of surgical operation time of the observation group was(1.72±0.41)h,and the average incidence of complication was(0.03±0.02)%,both of them of the observation group were significantly lower than those of the control group[(2.25±0.42)h and(0.05±0.03)%].The differences of them between two groups were statistically significant(t=9.00,4.08,P<0.05).The test scores of surgical operation of the observation group was also significantly higher than that of the control group(t=5.26,P<0.001).Conclusion:The developed simulation system for surgical operation with VR+intelligent scoring can significantly enhance users'surgical operation skills and improve learning outcomes,which has favorable prospects in future applications.