Objective To investigate clinical diagnostic efficacy of carotid artery non-enhanced high-resolution magnetic resonance imaging(MRI)for carotid artery stenosis.Methods We analyzed 122 cases of symptomatic carotid stenosis who underwent carotid endarterectomy(CEA)for the first time in our hospital from January to September 2024.Preoperative computed tomography angiography(CTA)and non-enhanced high-resolution MRI of the carotid artery were performed.According to the North American Symptomatic Carotid Endarterectomy Trial(NASCET)criteria,two radiologists independently measured degree of stenosis in 244 carotid arteries on CTA and MRI images.The sensitivity,specificity,accuracy,missed diagnosis rate,and misdiagnosis rate of MRI for the diagnosis of carotid stenosis were calculated with CTA as the control and carotid stenosis rates of≥50%,≥70%,and 100%as the thresholds.Results Taking the carotid stenosis rate of≥50%as the threshold,the sensitivity,specificity,accuracy,missed diagnosis rate,and misdiagnosis rate of MRI were 99.4%(161/162),100.0%(82/82),99.6%(243/244),0.6%(1/162),and 0.0%(0/82),respectively.Taking the carotid stenosis rate of≥70%as the threshold,the sensitivity,specificity,accuracy,missed diagnosis rate,and misdiagnosis rate of MRI were 100.0%(129/129),100.0%(115/115),100.0%(244/244),0.0%(0/129),and 0.0%(0/115),respectively.Taking the carotid stenosis rate of 100%as the threshold,the sensitivity,specificity,accuracy,missed diagnosis rate,and misdiagnosis rate of MRI were 100.0%(30/30),99.5%(213/214),99.6%(243/244),0.0%(0/30),and 0.5%(1/214),respectively.The Kappa values(κ)were in good agreement among different radiologist groups(CTA:κ=0.967,P=0.000;MRI:κ=0.956,P=0.000).Conclusion Carotid artery non-enhanced high-resolution MRI can accurately evaluate carotid stenosis.

Objective To investigate the nutritional quality characteristics of vitamin D3-fortified yogurt and explore its improving effect on vitamin D metabolism in the body under simulated weightlessness,thereby providing a theoretical basis for the development of functional foods.Methods Using reconstituted milk as the matrix and Vitamin D3(VD3)microcapsule powder as the fortifier,VD3-fortified yogurt was prepared.A systematic study was conducted to investigate the effects of different gradients(1.25 μg/100 mL,2.50 μg/100 mL,3.75 μg/100 mL,5.00 μg/100 mL,6.25 μg/100 mL)of VD3 microcapsule addition on its quality characteristics(titratable acidity,solid content,water-holding capacity,syneresis).In vivo assessments were conducted using a Sprague-Dawley(SD)rat tail-suspension model to simulate weightlessness.Levels in serum 25(OH)D3,1,25-(OH)2D3,calcium(Ca),and phosphorus(P)were detected using the enzyme-linked immunosorbent assay(ELISA)to evaluate its metabolic capacity.Results During fermentation(3 h),titratable acidity of VD?-fortified yogurt initially increased,then decreased,and eventually stabilized with rising microcapsule dosage,while total solid content remained consistent.WHC exhibited an initial increase followed by a decline,whereas syneresis showed an inverse trend.At an optimal dosage of 3.75 μg/100 mL,the yogurt displayed a dense and uniform network structure,characterized by non-Newtonian fluid behavior with shear-thinning properties.This formulation demonstrated robust structural stability under high-frequency mechanical stress,alongside desirable textural,flavor,and sensory attributes.Animal experiments revealed that the serum concentrations of 25(OH)D3,1,25-(OH)2D3,calcium,and phosphorus in the vitamin D?-fortified yogurt intervention group were significantly higher than those in the tail-suspended control group(P<0.05).Conclusion VD? microencapsulation technology effectively preserves and enhances the nutritional quality characteristics of yogurt and mitigates vitamin D metabolic dysregulation under simulated weightlessness.

Pyruvate kinase M2(PKM2)is closely linked to a variety of neurological disorders,involved in the onset and progression of a wide range of diseases,including Alzheimer's disease,Parkinson's disease,multiple sclerosis and traumatic brain injury through such mechanisms as aerobic glycolysis,oxidative stress,inflammation and apoptosis.This review is intended to provide an overview of the biological characteristics of PKM2 and its role in the pathophysiological mechanisms of neurological disorders.A better understanding of the correlations between PKM2 and the development of neurological diseases can offer new insights into and references for the clinical diagnosis and treatment of these conditions.

Objective:To utilize the left ventricular myocardial work（LVMW）technique for early identification of myocardial damage in patients with fabry disease（FD）.Methods:In an observational cross-sectional study，35 patients with FD who visited the Second Hospital of Hebei Medical University from February 2023 to April 2024 were included. They were categorized into two groups based on left ventricular mass index（LVMI）：the non-left ventricular hypertrophy group（LVH-FD group，14 cases）and the left ventricular hypertrophy group（LVH+FD group，21 cases）. Further gender-stratified analysis was performed on parameters related to left ventricular global longitudinal strain（LVGLS）and LVMW. Additionally，for the FD group with normal LVGLS，a comparison of their LVMW-related parameters was made with a control group. A control group consisting of 28 healthy subjects from the same period was selected for comparison. The LVGLS，global work index（LVGWI），global constructive work（LVGCW），global wasted work（LVGWW），and global work efficiency（LVGWE）of the three groups were analyzed using two-dimensional speckle tracking and non-invasive myocardial work techniques，and intergroup comparisons of these parameters were performed. Pearson's linear correlation was applied to analyse the correlation between LVGWI，LVGWE and LVMI.Results:① According to the LVMI grouping results，compared with the control group，the LVH-FD group showed decreased LVGWI（ P<0.05），while the LVH+FD group exhibited reductions in LVGLS，LVGWI，and LVGWE（all P<0.05）. Compared to the LVH-FD group，the LVH+FD group demonstrated lower LVGLS，LVGWI，and LVGWE（all P<0.05）. ② Gender subgroup analysis revealed that in the female subgroup，no statistically significant differences were observed in LVGLS，LVGWI，and LVGWE between the female control group and the female LVH-FD group（all P>0.05）. However，the female LVH+ FD group showed decreased LVGLS，LVGWI，and LVGWE compared to both the female control group（all P<0.05）and the female LVH-FD group（all P<0.05）. In the male subgroup，compared to the male control group，the male LVH-FD group had reduced LVGWI（ P<0.05）but no significant differences in LVGLS or LVGWE（both P>0.05）. The male LVH+ FD group displayed lower LVGLS，LVGWI，and LVGWE compared to both the male control group（all P<0.05）and the male LVH- FD group（all P<0.05）. ③Compared with the control group，the LVGLS-normal FD group had a reduced LVGWI（ P<0.05），while there were no statistically significant differences in LVGLS，LVGWE，LVGCW，and LVGWW between these two groups（all P>0.05）. ④LVGWI and LVGWE were negatively correlated with LVMI（ r=-0.617，-0.707；both P<0.001）. Conclusions:LVMW can detect early cardiac dysfunction in patients with FD and is of guiding value for their clinical management.

Objective:To evaluate the application of metagenomic next-generation sequencing（mNGS）in the identification of non-tuberculous mycobacteria（NTM）.Methods:A retrospective analysis was conducted on mNGS results of 358 bronchoalveolar lavage fluid（BALF）samples positive for NTM collected at the First Affiliated Hospital of Zhejiang University School of Medicine from February 2021 to January 2024. The analysis included the distribution of NTM species，the detection of mixed pathogens，and the performance of conventional mycobacterial detection methods.Results:The results showed that 362 strains of 15 NTM species were identified from 350 specimens，8 specimens were not precise to the species level. The most frequently detected species were Mycobacterium intracellulare（37.3%，135/362）， Mycobacterium abscessus（26.8%，97/362），followed by Mycobacterium avium（11.0%，40/362）， Mycobacterium kansasii（8.0%，29/362）and Mycobacterium chelonae（7.7%，28/362）. Single NTM species were detected in 339 specimens，while two or three NTM species were simultaneously detected in 11 specimens（3.1%，11/358）. Non-NTM microorganisms co-infected were detected in 53.4%（191/358）of NTM-positive BALF samples，including common pathogens such as Pseudomonas aeruginosa， Staphylococcus aureus，and Aspergillus fumigatus；and difficult-to-identify pathogens such as Legionella pneumophila and Talaromyces marneffei. In NTM-positive patients detected by mNGS，the results supported the diagnosis of NTM infection in 298 cases（298/358，83.2%）and 105 cases（105/358，29.3%）initiated anti-NTM treatment accordingly；while in 60 cases（60/358，16.8%）the positive results were considered as colonization or unrelated to clinical infection. For samples tested with acid-fast staining，mycobacterial liquid culture，and DNA microarray，the positivity rates for NTM were 31.5%（73/232），48.7%（57/117），and 43.0%（46/107），respectively. Conclusions:mNGS demonstrates advantages in identification of NTM. However，the test may detect multiple microorganisms，in that case，the interpretation with clinical and radiological results is requried to determine the main pathogens.

Flagella are important protein structures on the cell surface of bacteria and the main appendage for bacterial swimming. Flagella play a crucial role in bacterial motility, chemotaxis, pathogenicity, and environmental sensing. With the development of microscopic tracking technology and flagellum visualization tools, new forms of flagellar motility and increasing roles of flagella in the physiological activities of bacteria have been discovered. This review introduces the visualization methods of flagella and the applications of these methods in studying flagellar functions, giving insights into exploring the functions of flagella and laying a theoretical foundation for its future applications in inhibiting bacterial transmission and treating bacterial infections.
Flagella/physiology* ; Bacterial Physiological Phenomena ; Chemotaxis/physiology* ; Bacteria

Objective To investigate clinical diagnostic efficacy of carotid artery non-enhanced high-resolution magnetic resonance imaging(MRI)for carotid artery stenosis.Methods We analyzed 122 cases of symptomatic carotid stenosis who underwent carotid endarterectomy(CEA)for the first time in our hospital from January to September 2024.Preoperative computed tomography angiography(CTA)and non-enhanced high-resolution MRI of the carotid artery were performed.According to the North American Symptomatic Carotid Endarterectomy Trial(NASCET)criteria,two radiologists independently measured degree of stenosis in 244 carotid arteries on CTA and MRI images.The sensitivity,specificity,accuracy,missed diagnosis rate,and misdiagnosis rate of MRI for the diagnosis of carotid stenosis were calculated with CTA as the control and carotid stenosis rates of≥50%,≥70%,and 100%as the thresholds.Results Taking the carotid stenosis rate of≥50%as the threshold,the sensitivity,specificity,accuracy,missed diagnosis rate,and misdiagnosis rate of MRI were 99.4%(161/162),100.0%(82/82),99.6%(243/244),0.6%(1/162),and 0.0%(0/82),respectively.Taking the carotid stenosis rate of≥70%as the threshold,the sensitivity,specificity,accuracy,missed diagnosis rate,and misdiagnosis rate of MRI were 100.0%(129/129),100.0%(115/115),100.0%(244/244),0.0%(0/129),and 0.0%(0/115),respectively.Taking the carotid stenosis rate of 100%as the threshold,the sensitivity,specificity,accuracy,missed diagnosis rate,and misdiagnosis rate of MRI were 100.0%(30/30),99.5%(213/214),99.6%(243/244),0.0%(0/30),and 0.5%(1/214),respectively.The Kappa values(κ)were in good agreement among different radiologist groups(CTA:κ=0.967,P=0.000;MRI:κ=0.956,P=0.000).Conclusion Carotid artery non-enhanced high-resolution MRI can accurately evaluate carotid stenosis.

Objective:To evaluate the application of metagenomic next-generation sequencing（mNGS）in the identification of non-tuberculous mycobacteria（NTM）.Methods:A retrospective analysis was conducted on mNGS results of 358 bronchoalveolar lavage fluid（BALF）samples positive for NTM collected at the First Affiliated Hospital of Zhejiang University School of Medicine from February 2021 to January 2024. The analysis included the distribution of NTM species，the detection of mixed pathogens，and the performance of conventional mycobacterial detection methods.Results:The results showed that 362 strains of 15 NTM species were identified from 350 specimens，8 specimens were not precise to the species level. The most frequently detected species were Mycobacterium intracellulare（37.3%，135/362）， Mycobacterium abscessus（26.8%，97/362），followed by Mycobacterium avium（11.0%，40/362）， Mycobacterium kansasii（8.0%，29/362）and Mycobacterium chelonae（7.7%，28/362）. Single NTM species were detected in 339 specimens，while two or three NTM species were simultaneously detected in 11 specimens（3.1%，11/358）. Non-NTM microorganisms co-infected were detected in 53.4%（191/358）of NTM-positive BALF samples，including common pathogens such as Pseudomonas aeruginosa， Staphylococcus aureus，and Aspergillus fumigatus；and difficult-to-identify pathogens such as Legionella pneumophila and Talaromyces marneffei. In NTM-positive patients detected by mNGS，the results supported the diagnosis of NTM infection in 298 cases（298/358，83.2%）and 105 cases（105/358，29.3%）initiated anti-NTM treatment accordingly；while in 60 cases（60/358，16.8%）the positive results were considered as colonization or unrelated to clinical infection. For samples tested with acid-fast staining，mycobacterial liquid culture，and DNA microarray，the positivity rates for NTM were 31.5%（73/232），48.7%（57/117），and 43.0%（46/107），respectively. Conclusions:mNGS demonstrates advantages in identification of NTM. However，the test may detect multiple microorganisms，in that case，the interpretation with clinical and radiological results is requried to determine the main pathogens.

Objective:To utilize the left ventricular myocardial work（LVMW）technique for early identification of myocardial damage in patients with fabry disease（FD）.Methods:In an observational cross-sectional study，35 patients with FD who visited the Second Hospital of Hebei Medical University from February 2023 to April 2024 were included. They were categorized into two groups based on left ventricular mass index（LVMI）：the non-left ventricular hypertrophy group（LVH-FD group，14 cases）and the left ventricular hypertrophy group（LVH+FD group，21 cases）. Further gender-stratified analysis was performed on parameters related to left ventricular global longitudinal strain（LVGLS）and LVMW. Additionally，for the FD group with normal LVGLS，a comparison of their LVMW-related parameters was made with a control group. A control group consisting of 28 healthy subjects from the same period was selected for comparison. The LVGLS，global work index（LVGWI），global constructive work（LVGCW），global wasted work（LVGWW），and global work efficiency（LVGWE）of the three groups were analyzed using two-dimensional speckle tracking and non-invasive myocardial work techniques，and intergroup comparisons of these parameters were performed. Pearson's linear correlation was applied to analyse the correlation between LVGWI，LVGWE and LVMI.Results:① According to the LVMI grouping results，compared with the control group，the LVH-FD group showed decreased LVGWI（ P<0.05），while the LVH+FD group exhibited reductions in LVGLS，LVGWI，and LVGWE（all P<0.05）. Compared to the LVH-FD group，the LVH+FD group demonstrated lower LVGLS，LVGWI，and LVGWE（all P<0.05）. ② Gender subgroup analysis revealed that in the female subgroup，no statistically significant differences were observed in LVGLS，LVGWI，and LVGWE between the female control group and the female LVH-FD group（all P>0.05）. However，the female LVH+ FD group showed decreased LVGLS，LVGWI，and LVGWE compared to both the female control group（all P<0.05）and the female LVH-FD group（all P<0.05）. In the male subgroup，compared to the male control group，the male LVH-FD group had reduced LVGWI（ P<0.05）but no significant differences in LVGLS or LVGWE（both P>0.05）. The male LVH+ FD group displayed lower LVGLS，LVGWI，and LVGWE compared to both the male control group（all P<0.05）and the male LVH- FD group（all P<0.05）. ③Compared with the control group，the LVGLS-normal FD group had a reduced LVGWI（ P<0.05），while there were no statistically significant differences in LVGLS，LVGWE，LVGCW，and LVGWW between these two groups（all P>0.05）. ④LVGWI and LVGWE were negatively correlated with LVMI（ r=-0.617，-0.707；both P<0.001）. Conclusions:LVMW can detect early cardiac dysfunction in patients with FD and is of guiding value for their clinical management.

Objective To explore the effect of physical exercise on semen quality in order to provide basic data and theoretical basis for the improvement of male reproductive health.Methods A cross-sectional study was conducted on 1 059 males who visited the Reproductive Medicine Center of Shandong Maternal and Child Health Hospital for medical treatment and physical examination during July 2022 and April 2023.Their demographic data and physical exercise data were surveyed with questionnaires.Total sperm count,sperm concentration,total sperm motility,forward movement and normal sperm morphology were analyzed with computer aided analysis.Logistic regression model and multiple linear regression model were applied to analyze the effects of physical exercise on semen quality.Results After adjustment for confounding factors such as age,body mass index,alcohol consumption and smoking,logistic regression analysis showed that the risk of abnormal semen quality was increased in patients with moderate and heavy exercise intensity(OR=2.103,OR=2.229).Compared with the participants with physical exercise ≤10 min per session,those with＞20 min per session had a lower risk of abnormal semen quality(OR=0.357,0.256,0.289 for exercise time for＞20～30,＞30～60,＞60 min,respectively).There was no statistical significance between physical exercise frequency and semen quality(P＞0.05).The participants having exercise well were at a lower risk for abnormal semen quality(OR=0.711).Multiple linear regression analysis revealed that the frequency of physical exercise was an influencing factor of sperm concentration(β=7.474,95％CI:4.800～10.149,P＜0.05);the time of physical exercise per session was an influencing factor for total sperm count(β=20.632,95％CI:7.634～33.629);the intensity of physical exercise(β=-1.461,95％CI:-2.392～-0.530)and time of physical exercise per session(β=2.608,95％CI:1.404～3.812,P＜0.05)were influencing factors for percentage of forward motility sperm(P＜0.05);and physical exercise intensity(β=-1.934,95％CI:-3.238～-0.630),time of physical exercise per session(β=4.211,95％CI:2.525～5.897)and frequency of physical exercise(β=-2.008,95％CI:-3.480～-0.536)were influencing factors of total sperm motility(P＜0.05).Conclusion Physical exercise may affect semen quality,greater intensity of physical exercise may be a risk factor for abnormal semen quality,and longer physical exercise time may be related to improving semen quality.Therefore,proper physical exercise can help improve semen quality.