Objective:To explore the role and mechanism of neurotrophin-3(NT-3)in promoting neurological func-tion recovery after cerebral ischemia-reperfusion injury in rats.Methods:Twenty-four SD rats were randomly divided into sham operation group(Sham),middle cerebral artery occlusion/reperfusion(MCAO/R)group,and MCAO/R+NT-3 group.The neurological function scores of rats in each group were evaluated using the modified Garcia score.Western Blot was used to detect the expression of NT-3 and LC3B in brain tissues of rats.Culture dishes with the same density of neurons were randomly divided into normal group(Normal),oxygen-glucose deprivation(OGD)group,OGD+NT-3 group,OGD+NT-3+PF-06273340(TrkC inhibitor)group,OGD+NT-3+ZSTK474(PI3K inhibitor)group,and OGD+NT-3+CCT128930(AKT inhibitor)group.Western Blot was used to detect the expression of TrkC,the phosphorylation of PI3K/AKT,and LC3B in neurons.The morphological changes of neurons and the phenomenon of neuronal autophagy were observed using autophagy-specific fluorescent staining.Results:The animal experiment found that the expression of NT-3 increased in the brain tissue with ischemia-reperfusion injury(P＜0.05),and after the treatment with exogenous NT-3,the modified Garcia score increased(P＜0.05),and the level of autophagy weakened(P＜0.05).The cell experiment found that NT-3 can inhibit neuronal autophagy under ischemic hypoxia and maintain the neuronal morphology to the maximum extent.After using PF-06273340,the expression of p-PI3K and p-AKT de-creased(P＜0.05).After using ZSTK474 and CCT128930,the autophagy-inhibiting effect of NT-3 weakened(P＜0.05).Conclusion:NT-3 inhibits autophagy via the PI3K/AKT signaling pathway to maintain neuronal survival,thereby promoting the recovery of neurological function after cerebral ischemia-reperfusion injury in rats.

Objective:To introduce a surgical technique of " short distances and multi-segment" buried-guiding suture method and its effects in the surgery of early descent of prosthesis after augmentation mammaplasty.Methods:From August 2019 to January 2022, 15 cases of early descent of prosthesis after augmentation mammaplasty due to axillary approach breast augmentation for micromastia were admitted to the Plastic Surgery Department of Sichuan Provincial People′s Hospital, aged 23-35 years (27.3±3.6) and duration of dislocation from 16 to 35 days (23.8±5.8). There were 12 patients showed unilateral prosthesis drops and 3 patients showed bilateral prosthesis drops. " Short distances and multi-segment" buried-guiding suture method was used to solve the problem, i. e., 2-0 non-absorbable sutures were used to eliminate the lower pole of prosthetic cavity with " short distances and multi-segment" sutures. The distance from the nipple to the midline of the sternum, the distance from the sternotomy to the nipple, the distance from the nipple to the inframammary fold and the distance from the midclavicular point to the inframammary fold were measured bilaterally before and after surgery, and statistical analysis was performed to evaluate the efficacy of the " short distances and multi-segment" buried-guiding suture method for early descent of prosthesis after breast augmentation.Results:All incisions healed by first intention without complications such as hematoma, infection, or scar hyperplasia. 15 patients were followed up for 6-12 months (8.0±1.9). 14 patients were satisfied with the results after surgery, and 1 patient received satisfactory results after secondary surgery. The distance from nipple to inframammary fold was shortened by 0.8-1.4 cm after surgery (1.2±0.2), and the distance from mid-clavicle to inframammary fold was shortened by 1.0-1.6 cm (1.3±0.4), and the differences were statistically significant as compared with the values before surgery ( t=31.17, P<0.05; t=33.78, P<0.05). After surgery, the change in the distance from nipple to sternal was 0.1-0.3 cm (0.16±0.10), and the change in the distance from sternal notch to nipple was 0-0.2 cm (0.12±0.10), and the differences were not statistically significant ( P>0.05). Conclusions:With the advantages of simple operation, little trauma and no additional incision, the " short distance and multi-stage" buried-guiding suture method in the surgery of early descent of prosthesis after augmentation mammaplasty is worthy of clinical application.

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.

Objective To analyze thoracolumbar vertebral fractures(A3)treated by multiple manipulations using the finite element method and to explore the feasibility and advantages of the composite surgical method for treating thoracolumbar vertebral fractures(A3).Methods For three-dimensional reconstruction of thoracolumbar vertebral fractures(A3),the model was loaded with simulated hyperextension posture restoration,simple press restoration,press restoration under hyperextension posture,and composite manipulation.Subsequentially,the stress distribution of the model and displacement of the fractured vertebral body were observed.Results The equivalent stress under composite manipulation was 111.88 MPa,which was greater than that under other manipulations,and the stress under composite manipulation was more concentrated in the anterior and middle columns of the vertebral body.The peak stress under composite manipulation was 122.53 MPa,which was greater than that under other manipulations,and the stress was centrally distributed in fracture region of the fractured vertebral body.The fracture displacement under composite manipulation was 3.94 mm,which was greater than that under other manipulations,and the displacement distribution decreased from the posterior column to the anterior mid-column.The anterior longitudinal and intertransverse interligamentous ligaments of the fractured vertebral body experienced the greatest stress under composite manipulation,and the joint capsule ligaments experienced the greatest stress under hyperextension postural restoration,simple press restoration,and press restoration under the hyperextension posture.Conclusions Compound manipulation for treating thoracolumbar vertebral fractures(A3)has obvious advantages over other manipulative restorations and is a reasonable program for the current treatment of thoracolumbar vertebral fractures(A3).

Objective:To improve and optimize the modified surgical strategies for patents with Simon Ⅰ and Simon Ⅱ type of gynecomastia, based on their magnetic resonance imaging (MRI) features.Methods:Clinical data of 190 patients aged 12 to 56 years (mean age 26.7±8.6) with gynecomastia who underwent modified surgeries in the Department of Plastic Surgery of Peking Union Medical College Hospital from January 2017 to January 2023 were retrospectively analyzed. The study measured breast MRI images of 44 male patients to calculate the area ratio of the glands on the transverse plane via nipple. This provided insight into the physiological structure and the tissue distribution of gynecomastia for improving the modified surgical strategies. All 190 patients were treated with enhanced liposuction and " Pull-Through and Bottom-Up" techniques. The duration of operation, amount of liposuction and amount of glandular resection, postoperative complications were recorded, and postoperative satisfaction was investigated by questionnaire surveys.Results:MRI images of the 87-side male breast showed that the average area ratio of the glands on the transverse plane via nipple was (10.9±12.5) %. The most prevalent subtype of gynecomastia was branch pattern, accounting for 46.0%. The median surgical duration of 190 patients was 95 (65-210) minutes, the median liposuction volume was 300 (50-1 400) ml, and the median glandular removal was 19.9 (1.5-157.0) g. Eighty-eight patients (46.3%) went through followed up for more than 6 months post-posterative with an overall satisfaction score of 4.68±0.53. Postoperative complications occurred in 19 sides (5.1%), and the reoperation rate was 1.3%.Conclusions:The MRI imaging of gynecomastia shows that the component of patients′ breasts are mainly fat, with a small amount of glandular tissue and the dominant subtype is branch pattern. Enhanced liposuction combined with " Pull-Through and Bottom-Up" stab incision technique can be an effective treatment for Simon grades Ⅰ and Ⅱ gynecomastia. The method results in high patient satisfaction with fewer postoperative complications.

Objective:To analyze the clinical characteristics of pertussis cases diagnosed by two pathological detection methods: bacterial culture and real-time polymerase chain reaction (RT-PCR), and to explore the applicable value of two pathological detection methods in the diagnosis of pertussis.Methods:Bilateral nasopharyngeal swabs and clinical information of 165 children suspected of pertussis were collected by Hebei Children′s Hospital from April 2019 to January 2020. The bacterial culture and RT-PCR for nasopharyngeal swab specimens were performed in all cases. Chi-square test was used to analyze the cases of pertussis diagnosed by the above two methods.Results:Based on clinical diagnosis, the sensitivity of bacterial culture and RT-PCR for the diagnosis of pertussis was 61.70% (58/94) and 86.17% (81/94), and the specificity was 92.96% (66/71) and 71.83% (51/71), respectively. The positive rate of RT-PCR in children of all ages, seasons and cough courses is higher than that of bacterial culture. Children with pertussis diagnosed by bacterial culture and RT-PCR were basically similar in age, season, and cough course distribution, with the most common cases ≤3 months old, a high incidence trend in summer and autumn, and the course of coughing in children was mostly within 15-21days. The positive rate of bacterial culture in the diagnosis of pertussis in children is affected by the age of the children, and there are statistical differences between children in different age groups (χ2= 11.929, P=0.036). The positive rate of bacterial culture was the highest in children with >3 years old (51.85% [14/27]), followed by children with ≤3 months old (48.72% [19/39]), and the lowest in children with >6-12 months old (15.00% [3/20]). Moreover, the positive rate of bacterial culture in the diagnosis of pertussis in children is also affected by the cough course of the children, and there are statistical differences between children in different cough course groups (χ2=9.841, P=0.020). The positive rate of bacterial culture was the highest in children with cough course 15-21 days (49.23% [32/65]), followed by 43.59% (17/39) in children with cough course 8-14 days, and the lowest in children with cough course of less than 7 days (22.86% [8/35]). Conclusions:Compared with RT-PCR, bacterial culture has lower sensitivity and higher specificity in the detection of pertussis. These two detection methods have their own advantages and limitations. Medical institutions at all levels should comprehensively analyze different laboratory detection methods. Only by combining the two methods can the diagnostic value and level be effectively improved.

【Objective】 To analyze the HIV-, HCV- and HBV- NAT yield rate in different areas of Henan province, so as to provide the basis for disease prevention and control as well as the establishment of a unified quality control standard for nucleic acid testing(NAT) in the Henan province. 【Methods】 The number and prevalence of NAT yielding samples with isolated infectious virus, namely HIV, HCV and HBV, in 18 blood stations in Henan province from 2017~2019, as well as the trends were analyzed. The NAT quality of each laboratory and each testing system was analyzed according to the ratio of reactive individual donation(ID) results to reactive minipools(MP). 【Results】 The HBV, HCV and HIV ID-NAT yield numbers in 3 501 251 blood donations were HBV 2 606(74/100 000), HCV 21 (0.63/100 000), and HIV 34(1.00/100 000). The HBV ID-NAT yield rate showed an upward trend in the whole province from 2017 to 2019, while the prevalence of HIV and HCV ID-NAT yield didn′t differ significantly during three years. 5 kinds of NAT detection systems were applied in 18 blood centers. among which Ⅰ, Ⅱ, Ⅳ and Ⅴ were triplex detection systems. 2661 ID-reactive samples were implicated in 5 595 MP-reactive samples, with a resolution rate of 47.56%. The resolution rate of triplex NAT system Ⅰ, Ⅱ, Ⅳ and Ⅳ was 39.63%~47.95%, 40.43%~54.36%, 51.61% and 70.00%~45.45%, respectively. An upward trend in triplex NAT resolution rate was observed in 8 laboratories, i. e.B, D, E, F, I, K, L and Q, and an descending trend in A and C. The NAT system Ⅲ, a ID-NAT system, was used only by laboratory C, presenting a NAT-yield rate of 0.19% (282/145 474) and resolution rate of 46.45% (131/282). 【Conclusion】 The majority of NAT-yield of one infectious virus in Henan province is HBV, presenting annual increasing trend. The quality management of NAT laboratories should be strengthened as the divergence was seen in the performance of different NAT laboratories.

Objective:To screen the neutralizing epitope of enterovirus 71 (EV71) and determine the specific minimum amino acid sequence that triggers immunity for providing a theoretical basis for the development of synthetic peptide vaccines.Methods:EV71 neutralizing antibody-specific binding clones were panned and sequenced using a phage display random 12-peptide library to obtain the key sequences of neutralizing epitopes. A series of peptides containing the key sequences with N-terminal acetylation (AC) and C-terminal linking to Keyhole limpet hemocyanin (KLH) were synthesized. Serum samples were collected after immunizing mice with the modified peptides. Then the immunogenicity of the peptides and the neutralizing activity of serum samples were analyzed by Western blot, ELISA and neutralization test.Results:After three rounds of panning, cloning and sequencing, KQEKDL was identified as the key motif. The serum samples collected from the mice immunized with the modified series of peptides containing key motifs had different degrees of binding ability to EV71 and VP1 protein. The serum samples of mice immunized the synthetic peptide containing only the minimum key motif (AC-KQEKDL-KLH) had the strongest response to the other three peptides and EV71 and the highest neutralizing titer.Conclusions:The EV71 neutralizing epitope was successfully screened using the phage display random peptide library. The key motif of KQEKDL might be the specific minimum amino acid sequence that triggered the immune system. This study provides a theoretical basis for better understanding the immune response mechanism, evaluating the immunogenicity of the antigens and further research and development of polypeptide vaccines.

Objective:To investigate the clinical significance of suction blister transplantation in improving the efficacy of ReCell technique in the treatment of vitiligo.Methods:Patients were divided into three groups, namely, vitiligo patients without history of suction blister therapy, patients with ineffective suction blister therapy and patients with effective suction blister therapy. There were 30 patients in each group. All patients were treated with standard procedure of ReCell technique. The color recovery effect of leukoplakia was observed 3 and 6 months after operation, and the incidence of complications was also observed.Results:The effective rate of color recovery 3 and 6 months after operation were as follow: in patients without history of suction blister group, the effective rate of three months was 53.3%, and that of six months was 63.3%; in patients with ineffective suction blister group, the effective rate was 43.3% in three months and 50.0% in six months, and in patients with effective suction blister group, the effective rate was 76.7% in three months and 90.0% in six months. No obvious complications were observed in the three groups.Conclusions:For the treatment of stable vitiligo with ReCell technique, suction blister method is a simple and effective method for screening patients.

Objective:To investigate the effect of mechano-growth factor（MGF）on osteoclast activity and its mechanism.Methods:The RAW264.7 precursor osteoclast cell line was cultured with 25 ng/ml macrophage-colony stimulating factor（M-CSF）and 30 ng/ml receptor activator of NF-κB ligand（RANKL），and identified by tartrate resistant acid phosphatase（TRAP）staining after 7 days of culture. Western blot anslysis was used to determine the effect of 45 ng/ml MGF on the phosphoinositide-3-kinase/protein kinase B（PI3K/AKT）signaling pathway in separated osteoclasts，including levels of AKT，phosphorylation（p）-AKT，lactation mammalian target of rapamycin（mTOR），p-mTOR and TRAP at 0，4，8 and 12 hours. Real-time fluorescence quantitative PCR was used to expressions of TRAP in osteoclasts at 0，4，8 and 12 hours. The PI3K/Akt phosphorylation inhibitor LY294002（20 μmol/L）combined with MGF（45 ng/ml）was used to act on osteoclasts，and expression levels of Akt，p-Akt，mTOR，p-mTOR and TRAP were detected by Western blot at 0，4，8 and 12 hours.Results:After culturing RAW264.7 cells with M-CSF and RANKL for 7 days，a large number of osteoclasts with positive TRAP staining can be obtained. Western blot analysis showed expression levels of Akt and mTOR did not change significantly over time（ P>0.05），expression levels of p-Akt and p-mTOR increased continuously from（2.18±0.34）pg/ml and（0.83±0.10）pg/ml at 0 hour to（3.86±0.36）pg/ml and（1.56±0.19）pg/ml at 12 hours（ P<0.05），and expression level of TRAP decreased significantly over time，from（5.66±0.47）pg/ml at 0 hour to（3.76±0.38）pg/ml at 12 hours（ P<0.05）. Real-time fluorescence quantitative PCR analysis of expression of TRAP in osteoclasts showed that MGF inhibited the expression of TRAP in osteoclasts，which decreased from 1.02±0.06 at 0 hour to 0.53±0.11 at 12 hours（ P<0.05）. After acting LY294002 combined with MGF on osteoclasts，Western blot analysis showed expression levels of Akt and mTOR did not change significantly over time（ P>0.05），expression levels of p-AKT and p-mTOR decreased significantly from（3.28±0.18）pg/ml and（3.29±0.22）pg/ml at 0 hour to（2.06±0.34）pg/ml and（2.04±0.20）pg/ml at 12 hours（ P<0.05），and expression level of TRAP had no significant difference over time（ P>0.05）. Conclusions:MGF inhibits osteoclast activity by inhibiting the expression of TRAP in osteoclasts through PI3K/Akt signaling pathway. LY294002 inhibits the expression of PI3K/Akt signaling pathway in osteoclasts，further verifying the mechanism of MGF inhibiting osteoclast activity，and this finding puts forward new ideas for clinical prevention and treatment of osteoporosis.