Strain-hardening and suppression of shear-banding in rejuvenated bulk metallic glass.

Strain-hardening (the increase of flow stress with plastic strain) is the most important phenomenon in the mechanical behaviour of engineering alloys because it ensures that flow is delocalized, enhances tensile ductility and inhibits catastrophic mechanical failure1,2. Metallic glasses (MGs) lack the crystallinity of conventional engineering alloys, and some of their properties-such as higher yield stress and elastic strain limit3-are greatly improved relative to their crystalline counterparts. MGs can have high fracture toughness and have the highest known 'damage tolerance' (defined as the product of yield stress and fracture toughness)4 among all structural materials. However, the use of MGs in structural applications is largely limited by the fact that they show strain-softening instead of strain-hardening; this leads to extreme localization of plastic flow in shear bands, and is associated with early catastrophic failure in tension. Although rejuvenation of an MG (raising its energy to values that are typical of glass formation at a higher cooling rate) lowers its yield stress, which might enable strain-hardening5, it is unclear whether sufficient rejuvenation can be achieved in bulk samples while retaining their glassy structure. Here we show that plastic deformation under triaxial compression at room temperature can rejuvenate bulk MG samples sufficiently to enable strain-hardening through a mechanism that has not been previously observed in the metallic state. This transformed behaviour suppresses shear-banding in bulk samples in normal uniaxial (tensile or compressive) tests, prevents catastrophic failure and leads to higher ultimate flow stress. The rejuvenated MGs are stable at room temperature and show exceptionally efficient strain-hardening, greatly increasing their potential use in structural applications.

Diverse polarization angle swings from a repeating fast radio burst source.

Fast radio bursts (FRBs) are millisecond-duration radio transients1,2 of unknown origin. Two possible mechanisms that could generate extremely coherent emission from FRBs invoke neutron star magnetospheres3-5 or relativistic shocks far from the central energy source6-8. Detailed polarization observations may help us to understand the emission mechanism. However, the available FRB polarization data have been perplexing, because they show a host of polarimetric properties, including either a constant polarization angle during each burst for some repeaters9,10 or variable polarization angles in some other apparently one-off events11,12. Here we report observations of 15 bursts from FRB 180301 and find various polarization angle swings in seven of them. The diversity of the polarization angle features of these bursts is consistent with a magnetospheric origin of the radio emission, and disfavours the radiation models invoking relativistic shocks.

Interaction of smoking and aging on emphysema and small airways disease in asymptomatic healthy men by CT-based parametric response mapping analysis.

AIM: To explore whether small airway disease and emphysema were affected by the interaction between smoking and aging on chest computed tomography (CT) images of asymptomatic healthy men analysed using a quantitative imaging tool parametric response mapping (PRM). MATERIALS AND METHODS: In this retrospective study, 95 asymptomatic healthy men underwent biphasic chest CT. The PRM classifies lung as a percentage of normal (PRMNormal%), functional small airway disease (PRMfSAD%), and emphysema (PRMEmph%). The patients were divided into groups based on their age and smoking status. Multiple linear regression analysis was applied to explore the factors influencing lung injury. Simple effects analysis was performed to explore the interaction between different age groups and smoking status. RESULTS: The interaction between aging and smoking significantly affected PRMfSAD% and PRMEmph% (p<0.001). The age range 60-69 and smoking were associated with increased PRMfSAD% and PRMEmph% (p<0.05). Futher stratification into different age subgroups showed that smoking was associated with increased PRMfSAD% and PRMEmph% in the 50-59 year age group. Besides, smoking in the 50-59 and 60-69 years group was associated with decreased PRMNormal%, while smoking in the 60-69 years group did not significantly influence the prevalence of PRMfSAD% and PRMEmph% (p>0.05). CONCLUSIONS: PRM reveals the interplay between smoking and aging in the development of lung injury in asymptomatic healthy men. Aging and smoking are important factors of emphysema and small airway disease in the 50-69 years group. In the 60-69 years group, aging poses a greater risk of lung injury compared to smoking.

Disturbance of mitochondrial dynamics in myocardium of broilers with pulmonary hypertension syndrome.

1. The following study investigated the relationship between pulmonary hypertension syndrome (PHS) and mitochondrial dynamics in broiler cardiomyocytes.2. An animal model for PHS was established by injecting broiler chickens with CM-32 cellulose particles. Broiler myocardial cells were cultured under hypoxic conditions to establish an in vitro model. The ascites heart index, histomorphology, mitochondrial ultrastructure, and mitochondrial dynamic-related gene and protein expression were evaluated.3. The myocardial fibres from PHS broilers had wider spaces and were wavy and twisted and the number of mitochondria increased. Compared with the control group, the gene and protein expression levels were decreased for Opa1, Mfn1, and Mfn2 in the myocardium of PHS broilers. The gene and protein expression was significantly increased for Drp1 and Mff.4. This study showed that PHS in broilers may cause myocardial mitochondrial dysfunction, specifically by diminishing mitochondrial fusion and enhancing fission, causing disturbances in the mitochondrial dynamics of the heart.

[Initial experience of transcatheter edge-to-edge repair guided by only transesophageal echocardiography in the treatment of tricuspid insufficiency].

Objective: To evaluate the feasibility and safety of transcatheter tricuspid valve edge-to-edge repair guided by only transesophageal echocardiography (TEE). Methods: Patients with severe tricuspid regurgitation in Fuwai Yunnan Cardiovascular Hospital who met the inclusion criteria based on clinical and echocardiographic evaluationand underwent transcatheter tricuspid valve edge-to-edge repair between January 2022 and May 2023 were prospectively enrolled. The procedure was performed under general anesthesia with endotracheal intubation and solely guided by TEE. The patients underwent clinical evaluation, electrocardiogram and transthoracic echocardiography one month after the procedure. Results: A total of 22 patients (12 males and 10 females) were included, with an average age of (71.3±6.7) years. All 22 patients successfully underwent the transcatheter tricuspid valve edge-to-edge repair under TEE guidance, with an average of (1.5±0.6) clips implanted. Immediately after procedure, six patients had no or trace regurgitation, 15 patients had mild regurgitation, and one patient had moderate regurgitation. All 22 patients completed 30-day follow-up, with four patients having trace regurgitation, 17 patients having mild regurgitation, and one patient having moderate regurgitation. Echocardiographic measurements revealed that effective regurgitant orifice area, regurgitant volume, vena contracta width, and proximal isovelocity surface area radius significantly decreased after the procedure (all P<0.05). In addition, inferior vena cava width, right atrial volume, tricuspid annular diameter, and right ventricular end-diastolic diameter significantly improved (all P<0.05), but tricuspid annular plane systolic excursion and right ventricular fractional area change did not show significant differences compared with those before the procedure (both P>0.05). Conclusion: It has been preliminarily confirmed that transcatheter tricuspid valve edge-to-edge repair solely guided by TEE is feasible and safe, but requires more large-scale studies for further validation.

[Hepatitis B virus infection status and clinical characteristics in patients with rheumatoid arthritis].

Objective: To investigate the epidemiology of hepatitis B virus (HBV) infection in patients with rheumatoid arthritis (RA) in China and its association with RA disease characteristics. Methods: A cross-sectional study. A retrospective study was conducted on RA patients recruited from January 2001 to February 2023 in the Department of Rheumatology and Immunology, Sun Yat-Sen Memorial Hospital. Demographic and clinical data were collected including age, gender, disease duration, active smoking, RA disease activity, physical function, radiographic assessment, serological markers of HBV infection and liver function indicators. According to the status of HBV infection, RA patients were grouped as chronic HBV infection, resolved HBV infection and no HBV infection groups. The distribution of each group and the clinical characteristics of RA patients were analyzed. Results: Among 1 941 RA patients, 1 461 (75.3%) completed HBV screening, including 335 males (22.9%) and 1 126 females (77.1%), with a mean age of (55.4±13.1) years. The prevalence of chronic HBV infection was 10.1%(148/1 461), which was significantly higher in male patients than in females [14.6%(49/335) vs 8.8%(99/1 126), P<0.001], especially among those males born from 1970 to 1979[20.0%(7/35) vs 8.5%(17/201), P=0.037] and 1980-1989 [31.8%(7/22) vs 10.5%(14/133), P=0.007]. Among 148 RA patients with chronic HBV infection, there were 5 cases (3.4%) of chronic hepatitis B, 2 cases (1.4%) of HBV-associated cirrhosis and 1 case (0.7%) of hepatocellular carcinoma. The prevalence of resolved HBV infection was 57.6%(841/1 461). There were 472(32.3%) patients with no HBV infection and 267(56.6%) of them showed negative anti-HBs. Among all RA patients, 15 (1.0%) patients had abnormal liver function, of which 7 cases were drug-induced liver injury, 5 cases were chronic hepatitis B, 2 cases were non-alcoholic fatty liver disease, and 1 case was primary biliary cholangitis. Conclusion: Chronic HBV infection remains a common complication in RA patients in China, the infection rate is 10.1%, and the screening and management of HBV infection should be strengthened in clinical practice.

[Clinical characteristics of perimenopausal female patients with rheumatoid arthritis].

Objective: To explore the menopause status of patients with rheumatoid arthritis (RA) and clinical characteristics of perimenopausal RA patients. Methods: A cross-sectional study. Female RA patients were recruited retrospectively in the Sun Yat-Sen Memorial Hospital from August 2015 to August 2023. Clinical data were collected, including onset age, disease duration, RA disease activity indicators, functional assessment, and radiographic scores. According to menopausal status, the patients were categorized as pre-menopausal, perimenopausal and post-menopausal groups to explore their menopausal and clinical characteristics. Results: A total of 1 151 female patients were enrolled, with a mean age of (50.2±13.0) years. At enrollment, there were 470 (40.8%), 140 (12.2%) and 541 (47.0%) patients in pre-menopause, perimenopause and post-menopause status, respectively. The mean age of menopause was (49.0±4.2) years. Compared with pre-menopausal group, perimenopausal RA patients had higher disease activity indicators [clinical disease activity index (CDAI) 17 (6, 26) vs 10 (3, 19) ], higher levels of inflammation [erythrocyte sedimentation rate (ESR) 35 (21, 65) vs 26 (14, 44) mm/1h, C-reactive protein (CRP) 6.2 (3.2, 16.8) vs 3.3 (3.2, 13.6) mg/L], and a higher proportion of functional limitation [25.0%(35/140) vs 10.4%(49/470)] (all P<0.016 7); while there was no significant differences in disease activity[M(Q1, Q3)] [CDAI 17 (6, 26) vs 14 (6, 25)], levels of inflammation [ESR 35(21, 65) vs 42 (23, 72) mm/1h, CRP 6.2 (3.2, 16.8) vs 6.2 (3.3, 23.9) mg/L] and functional limitation [25.0%(35/140) vs 28.8%(156/541)] when compared with those in post-menopausal group (all P>0.016 7). In RA patients during the perimenopausal period, 49 cases (35.0%) developed RA during this period. Compared with patients with RA onset during reproductive age, patients with RA onset during the perimenopausal period had higher numbers of 28-joint tender joints [7 (2, 10) vs 4 (0, 8)], higher CDAI [20 (12, 29) vs 14 (4, 24)], and higher ESR [45 (25, 72) vs 32 (18, 56) mm/1h] (all P<0.05). Conclusion: Perimenopausal patients with RA have severe disease activity and functional limitation.

[Serum hepatitis B virus pregenomic RNA profiles in patients with chronic hepatitis B on long-term antiviral therapy].

Objective: To explore the clinical changes in levels of the new clinical marker serum hepatitis B virus (HBV) pregenomic RNA (pgRNA) in patients with chronic hepatitis B (CHB) with long-term antiviral therapy. Methods: 100 CHB cases who were initially treated with nucleos(t)ide analogues (NAs) at Peking University First Hospital were included. The levels of alanine aminotransferase (ALT), HBV DNA, hepatitis B e-antigen (HBeAg), and hepatitis B surface antigen (HBsAg) during the follow-up period were measured. The TaqMan-based real-time quantitative PCR method was used to detect serum HBV pgRNA levels. The independent sample t-test and Mann-Whitney U test were used to compare continuous variables between groups, while Pearson's χ (2) test and Fisher's exact test were used to compare categorical variables. Results: HBV pgRNA levels decreased significantly in patients who developed virological responses at 48 weeks (n = 54) during subsequent treatment compared to those who did not (n = 46). The HBV pgRNA level was lower in HBeAg-positive patients than in HBeAg-negative patients (P < 0.05 or P < 0.01). Patients with higher HBV DNA and HBeAg-positivity levels at baseline had a higher HBV pgRNA level following antiviral therapy. There was no statistically significant difference in HBV pgRNA levels in patients with different HBV pgRNA levels at baseline after antiviral therapy. There was no correlation between serum HBV pgRNA and HBsAg at baseline, but there was a correlation after long-term antiviral therapy, while there was a weak correlation between HBV pgRNA and HBsAg at the fifth and ninth years of antiviral therapy (r = 0.262, P = 0.031; r = 0.288, P = 0.008). Conclusion: HBV pgRNA levels were higher with higher HBV activity in CHB patients with long-term antiviral therapy.

[Discussion on the application status and method improvement of gas chromatography in occupational health inspection standards in China].

As a rapid, accurate and efficient analytical technique, gas chromatography is widely used in the detection of volatile organic compounds and inorganic small molecule toxins, and it is the main analytical method in the national testing standards for occupational health. The existing effective national standards of gas chromatography for the detection of some substances have low column efficiency, high toxicity of reagents, poor correlation of the standard curve and low desorption efficiency and other problems, some of which can be solved through method improvement. At the same time, with the use of new materials and new processes, new types of toxic substances are emerging, and there are still many occupational disease hazards of limited value without supporting detection methods, gas chromatography can be applied to the detection of some toxic substances to better complement the vacancy of China's occupational health detection methods. This paper analyzes the current situation of the application of gas chromatography in occupational health testing standards, discusses the improvement of some of these methods, and helps to promote the application and development of gas chromatography in occupational health testing.

Effects of gonadotropin-inhibitory hormone on testicular development and reproduction-related gene expression in roosters.

Gonadotropin-inhibitory hormone (GnIH) plays a crucial role in regulating reproduction in the hypothalamus of poultry and has been intensely investigated since its discovery. This study aimed to assess the effects of GnIH on testicular development, as well as on reproduction-related hormone release and gene expression levels in roosters. The administration of exogenous GnIH resulted in a significant reduction in testis weight, testis volume and semen quality (p < 0.05). Additionally, exogenous GnIH significantly up-regulates the expression of GnIH, and down-regulates the expression of PRL (p < 0.05). GnIH application also decreased the GnRH, vasoactive intestinal peptide (VIP) and luteinizing hormone ß subunit(LHß)gene expression levels. Meanwhile, by neutralizing the effects of endogenous GnIH through immunization, testicular development on day 150 in roosters was significantly promoted. Compared to the control condition, GnIH immunization significantly down-regulated the expression of the VIP and PRL genes (p < 0.05). In conclusion, we found that exogenous GnIH treatment inhibited testicular development, reduces PRL gene expression, and suppressed reproductive performance in roosters. Conversely, GnIH immunization down-regulated VIP and PRL genes, activates the reproductive system, and promotes the reproductive activity and testicular development of roosters.

[Antibacterial effect of low-temperature plasma on Enterococcus faecalis in dentinal tubules in vitro].

OBJECTIVE: To construct a model of Enterococcus faecalis (E. faecalis) infection in dentinal tubules by gradient centrifugation and to evaluate the antibacterial effect of low-temperature plasma on E. faecalis in dentinal tubules. METHODS: Standard dentin blocks of 4 mm×4 mm×2 mm size were prepared from single root canal isolated teeth without caries, placed in the E. faecalis bacterial solution, centrifuged in gradient and incubated for 24 h to establish the model of dentinal tubule infection with E. faecalis. The twenty dentin blocks of were divided into five groups, low-temperature plasma jet treatment for 0, 5 and 10 min, calcium hydroxide paste sealing for 7 d and 2% chlorhexidine gel sealing for 7 d. Scanning electron microscopy and confocal laser scanning microscope were used to assess the infection in the dentinal tubules and the antibacterial effect of low-temperature plasma. RESULTS: The results of scanning electron microscopy and confocal laser scanning microscopy showed that after 24 h of incubation by gradient centrifugation, E. faecalis could fully enter the dentinal tubules to a depth of more than 600µm indicating that this method was time-saving and efficient and could successfully construct a model of E. faecalis infection in dentinal tubules. Low-temperature plasma could enter the dentinal tubules and play a role, the structure of E. faecalis was still intact after 5 min of low-temperature plasma treatment, with no obvious damage, and after 10 min of low-temperature plasma treatment, the surface morphology of E. faecalis was crumpled and deformed, the cell wall was seriously collapsed, and the normal physiological morphology was damaged indicating that the majority of E. faecalis was killed in the dentinal tubules. The antibacterial effect of low-temperature plasma treatment for 10 min exceeded that of the calcium hydroxide paste sealing for 7 d and the 2% chlorhexidine gel sealing for 7 d. These two chemicals had difficulty entering deep into the dentinal tubules, and therefore only had a few of antibacterial effect on the bacterial biofilm on the root canal wall, and there was also no significant damage to the E. faecalis bacterial structure. CONCLUSION: Gradient centrifugation could establish the model of E. faecalis dentin infection successfully. Low-temperature plasma treatment for 10 min could kill E. faecalis in dentinal tubules effectively, which is superior to the calcium hydroxide paste sealing for 7 d and the 2% chlorhexidine gel sealing for 7 d.

[Effect of various intracanal materials on the diagnostic accuracy of cone-beam computed tomography in vertical root fractures].

OBJECTIVE: To study the effect of various intracanal materials on the accuracy of oral maxillofacial cone-beam computed tomography (CBCT) for the diagnosis of vertical root fracture (VRF). METHODS: A total of twenty-four structurally intact single root canal dried and isolated teeth extracted for orthodontic treatment or periodontal disease were collected. The teeth were decrowned along the cemento-enamel junction (CEJ) and then used as samples for the study after conventional root canal preparation and post preparation. The 24 samples were divided into two groups with 12 samples in each group. Group A was the control group (no VRF group). According to intracanal materials, they were divided into five subgroups: blank group, fiber post group, gutta-percha point group, titanium post group and gold-palladium post group. Group B was the experimental group (VRF group), and subgroups were grouped as above. The VRF model was prepared by a unified method in the VRF group: the root was completely fractured in the buccolingual direction with a custom root canal nail and then cemented and reset. The control group was not subjected to the simulation of VRF. Titanium post and gold-palladium post were made according to the individuality of the root canal preparation, and the tightness of the post to the root canal wall was confirmed by X-ray radiograph. Then all the samples were scanned by CBCT in the isolate swine mandibular alveolar sockets. The diagnostic accuracy was statistically analyzed via blind interpretation by experienced endodontic specialists and oral and maxillofacial medical imaging specialists. RESULTS: The accuracy of the diagnosis of VRF in the blank group, fiber post group, gutta-percha point group, titanium post group, and gold-palladium post group in CBCT was 95.83%, 91.67%, 87.50%, 79.17%, and 45.83%, respectively. Compared with the blank group, the differences were not statistically significant in the fiber post group (P>0.999), the gutta-percha point group (P=0.500) and the titanium post group (P=0.125). The lowest diagnostic accuracy of VRF was found in the gold-palladium post group, and the difference was statistically significant compared with all other groups (P < 0.001). CONCLUSION: Various intracanal materials have different degrees of influence on the diagnostic accuracy of VRF diagnosis in CBCT. The influence of fiber post, gutta-percha point and titanium post was small, while the influence of gold-palladium post was significant.

[X-ray evaluation of pulp calcification in adult permanent teeth after pulpotomy].

OBJECTIVE: To compare the clinical effects of pulpotomy with two kinds of calcium silicate materials, and to evaluate the formation of dentin bridge and pulp calcification after pulpotomy of adult permanent teeth. METHODS: Patients who visited the General Department of Peking University School and Hospital of Stomatology from November 2017 to September 2019 and planned for pulpotomy on permanent premolars and molars with carious exposed pulp were selected. They were randomly divided into two groups. Bioceramic putty material iRoot BP (iRoot group, n=22) and mineral trioxide aggregate MTA (MTA group, n=21) were used as pulp capping agents, respectively. The patients were recalled after one year and two years. The clinical efficacy, dentin bridge index (DBI) and pulp calcification index (PCI) were recorded. Blinding method was used for the patients and evaluators. RESULTS: There was no significant difference in gender, mean age, dentition and tooth position between the two groups (P>0.05). Seven cases were lost during the first year (4 cases in iRoot group and 3 cases in MTA group). In the iRoot group, 1 case had transient sensitivity at the time of 1-year follow-up. The cure rate of the two groups was 100% at the time of 2-year follow-up. The proportion of dentin bridge formation was 38.9% one year after operation, 55.6% two years after operation. The proportion of partial or even complete disappearance of root canal image was 5.6% before operation, 38.9% and 55.6% one and two years after operation, respectively. The difference was statistically significant by rank sum test (P < 0.05). There was no significant difference in dentin bridge formation and pulp calcification between the two groups (P < 0.05). DBI and PCI after operation was as the same as those before operation (44.4% cases of DBI and 25% cases of PCI) or gradually increased (55.6% cases of DBI and 75% cases of PCI). Spearman's nonparametric correlation analysis showed that age was positively correlated with preoperative pulp calcification index (PCI0, P < 0.05), but not with the dentin bridge index (DBI1, DBI2), pulp calcification index (PCI1, PCI2) and the degree of change (DBI2 vs. DBI1, PCI1 vs. PCI0, PCI2 vs. PCI0) 1-year and 2-year after operation (P>0.05). CONCLUSION: According to this study, good clinical effects were obtained within 2-year after pulpotomy of adult permanent teeth with MTA and iRoot. In some cases, the root canal system had a tendency of calcification aggravation, and there was no statistical difference in the development of this trend between the two groups.

[Analysis of biofilm-forming ability and drug resistance for Hypervirulent Klebsiella pneumoniae].

Investigate the biofilm-forming ability and drug resistance of Hypervirulent Klebsiella pneumoniae (HvKP) to provide scientific basis for the treatment of HvKP-infection. A total of 96 Klebsiella pneumoniae strains isolated from clinical infection specimens in Changsha Central Hospital from January to December in 2021 were retrospectively collected, and the clinical data of patients were collected. The string test preliminarily distinguished between HvKP and classic Klebsiella pneumoniae (CKP). The biofilm-forming ability of clinical strains of Klebsiella pneumoniae (KP) was determined by microplate method. The Vitek 2 Compact automatic microbial identification/drug sensitivity analysis system was used for bacterial identification and drug sensitivity test. The clinical data of patients, biofilm forming ability and drug resistance in the HvKP group and those in the CKP group were compared and analyzed. The results showed that a total of 20 strains of HvKP were isolated from 96 non-repetitive KP, and the detection rate was 20.8%. HvKP mainly come from respiratory specimens, up to 75.0%.The prevalence of hepatobiliary diseases and the infection rate of multiple sites in patients with HvKP infection were higher than those in patients with CKP infection, and the difference was statistically significant(χ2=5.184,7.488;P=0.023,0.006).There was no significant difference between the two groups in terms of gender, age, ICU admission, hypertension, diabetes, coronary heart disease, lung disease, urinary system disease, central nervous system disease and laboratory test indexes (all P>0.05).17 (85.0%) strains of HvKP can form biofilm, including 2 strains with weak biofilm-forming ability (10.0%), 10 strains with moderate biofilm-forming ability (50.0%) and 5 strains with strong biofilm-forming ability (25.0%). Among the 76 CKP, 71 (93.4%) could form biofilm, including 13 (17.1%) with weak biofilm-forming ability, 30(39.5%) with moderate biofilm-forming ability and 28 (36.8%) with strong biofilm-forming ability. There was no significant difference in biofilm-forming ability between HvKP and CKP (χ2=1.470,P=0.225).The overall resistance rate of HvKP was not high, but a multi-resistant HvKP resistant to carbapenems was found. The detection rate of multi-resistant HvKP (5.0%) was lower than that of multi-resistant CKP (28.9%), and the difference was statistically significant (χ2=4.984, P=0.026).The resistance rate of HvKP to piperacillin/tazobactam, aztreonam, ciprofloxacin, levofloxacin, ceftazidime, cefepime, tobramycin, minocycline, doxycycline, and compound sulfamethoxazole was lower than that of CKP, and the difference was statistically significant (all P<0.05). In conclusion, most of hypervirulent Klebsiella pneumoniae can form biofilm in this study, but the difference of biofilm-forming ability is not obvious compared with classic Klebsiella pneumoniae. HvKP maintains high sensitivity to commonly used antibacterial drugs, but the drug resistance monitoring of the bacteria cannot be ignored.

[Study on the relationship between the age at natural menopause and postmenopausal metabolic syndrome].

To explore the relationship between the early or delayed age at natural menopause and metabolic syndrome (MS) in women. A total of 4 734 natural menopausal women who completed the baseline survey from November 2017 to January 2020 in the Guangzhou Middle-aged and Elderly Chronic Disease Prospective Cohort Study were selected in this cross-sectional study. Data on general demographic characteristics, disease history and female physiological health indicators were collected. Logistic regression model and restricted cubic spline curve were used to analyze the relationship between the age at natural menopause and MS. The results showed that the mean age of the subjects was (60±6) years old. The median (Q1,Q3) age at natural menopause was 50 (49, 52) years old, and the prevalence of MS was 14.8%(699/4 734). After adjusting for confounders, the age at natural menopause was closely related to MS in an approximate"U"shape. Compared with the group of normal age at natural menopause, the early age at menopause (OR=1.52, 95%CI: 1.12-2.06) and delayed age at menopause (OR=1.77, 95%CI: 1.36-2.30) had a higher risk of MS. In the group with time since menopause ≤6 years and 7-9 years, the risk of MS in the group with delayed age at menopause was 2.40 times (95%CI: 1.54-3.75) and 2.19 times (95%CI: 1.11-4.31) higher than that in the group with normal menopausal age, respectively. In conclusion, the early and delayed age at natural menopause increased the risk of MS. The increased risk of MS in delayed age at natural menopause mainly occurred within 10 years since menopause.

[Drug resistance and genomic characteristics of Salmonella enterica serovar London from clinical and food sources in Hangzhou City from 2017 to 2021].

Objective: To analyze the drug resistance and genomic characteristics of Salmonella enterica serovar London isolated from clinical and food sources in Hangzhou City from 2017 to 2021. Methods: A total of 91 Salmonella enterica serovar London strains isolated from Hangzhou City from 2017 to 2021 were analyzed for drug susceptibility, pulsed field gel electrophoresis (PFGE) typing and whole genome sequencing. Multilocus sequence typing (MLST), core genome multilocus sequence typing (cgMLST) and detection of drug resistance genes were performed by using the sequencing data. Phylogenetic analysis was conducted to compare the 91 genomes from Hangzhou City with 347 genomes from public databases. Results: No significant difference in the drug resistance rate was observed between clinical strains and food strains to 18 drugs in Hangzhou City(all P>0.05), and the multidrug resistance (MDR) rate was 75.8% (69/91). Most strains were resistant to 7 drug classes simultaneously. One strain was resistant to Polymyxin E as well as positive for mcr-1.1, and 50.5% (46/91) of the strains were resistant to Azithromycin and were positive for mph(A). All 91 Salmonella enterica serovar London strains were ST155, which were subdivided into 44 molecular types by PFGE and 82 types by cgMLST. Phylogenetic analysis showed that most strains from Hangzhou City (83/91) were clustered together, and a small number of human isolates from Europe, North America and pork isolates from Hubei and Shenzhen were mixed in the cluster. Other strains from Hangzhou City (8/91) were closely related to strains from Europe, America and Southeast Asia. Strains isolated from pork were the most closely related to clinical strains. Conclusion: The epidemic of Salmonella enterica serovar London in Hangzhou City is mainly caused by the spread of ST155 strains, which is mainly transmitted locally. At the same time, cross-region transmission to Europe, North America, Southeast Asia, and other provinces and cities in China may also occur. There is no significant difference in the drug resistance rate between clinical strains and food strains, and a high level of MDR is found in the strains. Clinical infection of Salmonella enterica serovar London may be closely related to pork consumption in Hangzhou City.

[A follow-up study on the pain changes trend and effects in patients diagnosed with herpes zoster in Beijing City].

Objective: To understand the changes in pain and its effects in patients with the diagnosis of herpes zoster. Methods: A total of 3 487 patients diagnosed with herpes zoster (HZ) for the first time at the outpatient department of Miyun District Hospital from January 1, 2017, to December 31, 2019, were included in the study. The information of patients was registered and issued with a record card. Patients were required to record the time of pain and rash by themselves. Telephone follow-up was conducted at 21, 90, 180 and 365 days after the onset of rashes, including hospitalization, location of rash and pain, and the time of start and end. The impact of pain on life was evaluated by the Zoster Brief Pain Inventory (ZBPI). Results: The age of 2 999 HZ patients included in the analysis were (53±16) years old, including 1 377 (45.91%) males and 1 903 (63.45%) patients aged 50 years and older. After 21 days of rash, mild, moderate and severe pain accounted for 20.87% (626 cases), 37.98% (1 139 cases) and 33.81% (1 014 cases), respectively. Only 5.07% (152 cases) had no pain or discomfort, and 2.27% (68 cases) had no pain but discomfort. Most of the pain sites were consistent with the rash sites. The chest and back and waist and abdomen were the most common, accounting for 35.58% (1 067 cases) and 29.18% (875 cases), respectively, followed by the limbs and face and neck, accounting for 16.74% (502 cases) and 16.40% (492 cases), respectively. The M (Q1, Q3) of pain days in the HZ patients was 14 (8, 20) days, and the incidence of post-herpetic neuralgia (PHN) was 6.63% (171/2 580) (excluding 419 patients who refused to visit or lost to visit on 90 days after the onset of rash). The pain score of HZ patients within 21 days after the rash was (5.19±2.73) points, and the pain score of PHN patients was (7.61±2.13) points, which was significantly higher than that of non-PHN patients [(5.04±2.69) points] (P<0.001). Daily activities, emotions, walking ability, work, social interaction, sleep and recreation were affected for 21 days after the rash in HZ patients, ranging from 60.79% to 83.83%, with sleep being the most affected (83.83%). The impact scores of pain and life dimensions in PHN patients ranged from 4.59 to 7.61 points on the ZBPI scale, which were higher than those in non-PHN patients (2.49-5.04) (t values ranged from 8.86 to 11.67, all P values <0.001). Conclusion: The proportion of pain in HZ patients after the diagnosis is high, and the pain is more obvious in patients with PHN and HZ patients aged 50 and older, which has a greater impact on their daily lives.

[HbA1c comparison and diagnostic efficacy analysis of multi center different glycosylated hemoglobin detection systems].

Objective: Compare and analyze the results of the domestic Lanyi AH600 glycated hemoglobin analyzer and other different detection systems to understand the comparability of the detection results of different detectors, and establish the best cut point of Lanyi AH600 determination of haemoglobin A1c (HbA1c) in the diagnosis of diabetes. Methods: Multi center cohort study was adopted. The clinical laboratory departments of 18 medical institutions independently collected test samples from their respective hospitals from March to April 2022, and independently completed comparative analysis of the evaluated instrument (Lanyi AH600) and the reference instrument HbA1c. The reference instruments include four different brands of glycosylated hemoglobin meters, including Arkray, Bio-Rad, DOSOH, and Huizhong. Scatter plot was used to calculate the correlation between the results of different detection systems, and the regression equation was calculated. The consistency analysis between the results of different detection systems was evaluated by Bland Altman method. Consistency judgment principles: (1) When the 95% limits of agreement (95% LoA) of the measurement difference was within 0.4% HbA1c and the measurement score was≥80 points, the comparison consistency was good; (2) When the measurement difference of 95% LoA exceeded 0.4% HbA1c, and the measurement score was≥80 points, the comparison consistency was relatively good; (3) The measurement score was less than 80 points, the comparison consistency was poor. The difference between the results of different detection systems was tested by paired sample T test or Wilcoxon paired sign rank sum test; The best cut-off point of diabetes was analyzed by receiver operating characteristic curve (ROC). Results: The correlation coefficient R2 of results between Lanyi AH600 and the reference instrument in 16 hospitals is≥0.99; The Bland Altman consistency analysis showed that the difference of 95% LoA in Nanjing Maternity and Child Health Care Hospital in Jiangsu Province (reference instrument: Arkray HA8180) was -0.486%-0.325%, and the measurement score was 94.6 points (473/500); The difference of 95% LoA in the Tibetan Traditional Medical Hospital of TAR (reference instrument: Bio-Rad Variant II) was -0.727%-0.612%, and the measurement score was 89.8 points; The difference of 95% LoA in the People's Hospital of Chongqing Liang Jiang New Area (reference instrument: Huizhong MQ-2000PT) was -0.231%-0.461%, and the measurement score was 96.6 points; The difference of 95% LoA in the Taihe Hospital of traditional Chinese Medicine in Anhui Province (reference instrument: Huizhong MQ-2000PT) was -0.469%-0.479%, and the measurement score was 91.9 points. The other 14 hospitals, Lanyi AH600, were compared with 4 reference instrument brands, the difference of 95% LoA was less than 0.4% HbA1c, and the scores were all greater than 95 points. The results of paired sample T test or Wilcoxon paired sign rank sum test showed that there was no statistically significant difference between Lanyi AH600 and the reference instrument Arkray HA8180 (Z=1.665,P=0.096), with no statistical difference. The mean difference between the measured values of the two instruments was 0.004%. The comparison data of Lanyi AH600 and the reference instrument of all other institutions had significant differences (all P<0.001), however, it was necessary to consider whether it was within the clinical acceptable range in combination with the results of the Bland-Altman consistency analysis. The ROC curve of HbA1c detected by Lanyi AH600 in 985 patients with diabetes and 3 423 patients with non-diabetes was analyzed, the area under curve (AUC) was 0.877, the standard error was 0.007, and the 95% confidence interval 95%CI was (0.864, 0.891), which was statistically significant (P<0.001). The maximum value of Youden index was 0.634, and the corresponding HbA1c cut point was 6.235%. The sensitivity and specificity of diabetes diagnosis were 76.2% and 87.2%, respectively. Conclusion: Among the hospitals and instruments currently included in this study, among these four hospitals included Nanjing Maternity and Child Health Care Hospital in Jiangsu Province (reference instrument: Arkray HA8180), Tibetan Traditional Medical Hospital of TAR (reference instrument: Bio-Rad Variant Ⅱ), the People's Hospital of Chongqing Liang Jiang New Area (reference instrument: Huizhong MQ-2000PT), and the Taihe Hospital of traditional Chinese Medicine in Anhui Province (reference instrument: Huizhong MQ-2000PT), the comparison between Lanyi AH600 and the reference instruments showed relatively good consistency, while the other 14 hospitals involved four different brands of reference instruments: Arkray, Bio-Rad, DOSOH, and Huizhong, Lanyi AH600 had good consistency with its comparison. The best cut point of the domestic Lanyi AH600 for detecting HbA1c in the diagnosis of diabetes is 6.235%.

[Diagnostic value of novel hepatic fibrosis markers in assessing cirrhosis in patients with chronic hepatitis C].

Objective: To investigate the efficacy of chitinase-3-like protein 1 (CHI3L1) and Golgi protein 73 (GP73) in the diagnosis of cirrhosis and the dynamic changes of CHI3L1 and GP73 after HCV clearance in patients with chronic hepatitis C (CHC) treated with direct-acting antiviral drugs (DAAs). The comparison of continuous variables of normal distribution were statistically analyzed by ANOVA and t-test. The comparison of continuous variables of non-normal distribution were statistically analyzed by rank sum test. The categorical variables were statistically analyzed by Fisher's exact test and χ(2) test. Correlation analysis was performed using Spearman correlation analysis. Methods: Data of 105 patients with CHC diagnosed from January 2017 to December 2019 were collected. The receiver operating characteristic curve (ROC curve) was plotted to study the efficacy of serum CHI3L1 and GP73 for the diagnosis of cirrhosis. Friedman test was used to compare CHI3L1 and GP73 change characteristics. Results: The areas under the ROC curve for CHI3L1 and GP73 in the diagnosis of cirrhosis at baseline were 0.939 and 0.839, respectively. Serum levels of CHI3L1 and GP73 in the DAAs group decreased significantly at the end of treatment compared with baseline [123.79 (60.25, 178.80) ng/ml vs. 118.20 (47.68, 151.36) ng/ml, P = 0.001; 105.73 (85.05, 130.69) ng/ml vs. 95.52 (69.52, 118.97) ng/ml, P = 0.001]. Serum CHI3L1 and GP73 in the pegylated interferon combined with ribavirin (PR) group were significantly lower at the end of 24 weeks of treatment than the baseline [89.15 (39.15, 149.74) ng/ml vs. 69.98 (20.52, 71.96) ng/ml, P < 0.05; 85.07 (60.07, 121) ng/ml vs. 54.17 (29.17, 78.65) ng/ml, P < 0.05]. Conclusion: CHI3L1 and GP73 are sensitive serological markers that can be used to monitor the fibrosis prognosis in CHC patients during treatment and after obtaining a sustained virological response. Serum CHI3L1 and GP73 levels in the DAAs group decreased earlier than those in the PR group, and the serum CHI3L1 levels in the untreated group increased compared with the baseline at about two years of follow-up.

[Comparison on the efficacy of Chinese-made novel-designed mechanical-locked and elastic self-locked transcatheter edge-to-edge repair system in the treatment of patients with functional mitral regurgitation].

Objective: To evaluate and compare the short-term efficacy of domestic mechanical-locked (Clip2Edge) and elastic self-locked (ValveClip) transcranial mitral valve edge-to-edge interventional repair (TEER) devices in the treatment of functional mitral regurgitant valves. Methods: In this retrospective non-randomized comparative study, patients underwent TEER procedure in Fuwai Yunnan Cardiovascular Disease Hospital from May 2022 to April 2023 for heart failure combined with moderate to severe or severe functional mitral valve were divided into Clip2Edge and ValveClip groups based on the TEER system used. Baseline, perioperative, and postoperative 30 d follow-up data were collected and compared between the two groups. The primary outcome was the success rate on the 30 d post operation, while secondary outcomes included immediate postoperative technical success rate and the incidence of all-cause mortality on the 30 d post operation, readmission rate of acute heart failure, cerebral infarction, severe bleeding, and other serious adverse events rates. Results: A total of 60 patients were enrolled, 34 patients were in the Clip2Edge group and 26 in the ValveClip group, mean age was (63.8±9.3) years, and 24 patients (40%) were female. There were no significant differences in baseline data of age, cardiac function, comorbidities, mitral regurgitation 4+(19(73%) vs. 29(85%)), the end-diastolic volume of left ventricle ((220.8±91.2) ml vs. (210.8±71.7) ml) between the two groups (all P>0.05). The technical success rate immediately after the procedure was 100%. There were no readmission of acute heart failure, death, cerebral infarction, severe bleeding, and other serious adverse events up to the 30 d follow-up. Device success rate was similar between the ValveClip group (24 cases (100%)) and the Clip2Edge group (27 cases (96%)) (P>0.05). Conclusion: Both types of novel domestic TEER devices are safe and feasible in treating patients with functional mitral regurgitation.