ObjectiveIn nature, objects cast shadows due to illumination, forming the basis for stereoscopic perception. Birds need to adapt to changes in lighting (meaning they can recognize stereoscopic shapes even when shadows look different) to accurately perceive different three-dimensional forms. However, how neurons in the key visual brain area in birds handle these lighting changes remains largely unreported. In this study, pigeons (Columba livia) were used as subjects to investigate how neurons in pigeon’s ventrolateral mesopallium (MVL) represent stereoscopic shapes consistently, regardless of changes in lighting. MethodsVisual cognitive training combined with neuronal recording was employed. Pigeons were first trained to discriminate different stereoscopic shapes (concave/convex). We then tested whether and how light luminance angle and surface appearance of the stereoscopic shapes affect their recognition accuracy, and further verify whether the results rely on specify luminance color. Simultaneously, neuronal firing activity of neurons was recorded with multiple electrode array implanted from the MVL during the presentation of difference shapes. The response was finally analyzed how selectively they responded to different stereoscopic shapes and whether their selectivity was affected by the changes of luminance condition (like lighting angle) or surface look. Support vector machine (SVM) models were trained on neuronal population responses recorded under one condition (light luminance angle of 45°) and used to decode responses under other conditions (light luminance angle of 135°, 225°, 315°) to verify the invariance of responses to different luminance conditions. ResultsBehavioral results from 6 pigeons consistently showed that the pigeons could reliably identify the core 3D shape (over 80% accuracy), and this ability wasn’t affected by changes in light angle or surface appearance. Statistical analysis of 88 recorded neurons from 6 pigeons revealed that 83% (73/88) showed strong selectivity for specific 3D shapes (selectivity index>0.3), and responses to convex shapes were consistently stronger than to concave shapes. These shape-selective responses remained stable across changes in light angle and surface appearance. Neural patterns were consistent under both blue and orange lighting. The decoding accuracy achieves above 70%, suggesting stable responses under different conditions (e.g., different lighting angles or surface appearance). ConclusionNeurons in the pigeon MVL maintain a consistent neural encoding pattern for different stereoscopic shapes, unaffected by illumination or surface appearance. This ensures stable object recognition by pigeons in changing visual environments. Our findings provide new physiological evidence for understanding how birds achieve stable perception (“invariant neural representations”) while coping with variations in the visual field.

ObjectiveFat infiltration has been shown to be closely related to muscle mass loss and a variety of muscle diseases. This study proposes a method based on phase-angle electrical impedance tomography (ΦEIT) to visualize the electrical characteristic response caused by muscle fat infiltration, aiming to provide a new technical means for early non-invasive detection of muscle mass deterioration. MethodsThis study was divided into two parts. First, a laboratory pork model was constructed to simulate different degrees of fat infiltration by injecting1 ml or 2 ml of emulsified fat solution into different muscle compartments, and the phase angle images were reconstructed using ΦEIT. Second, a human experiment was conducted to recruit healthy subjects (n=8) from two age groups (20-25 years old and 26-30 years old). The fat content percentage η_fat of the left and right legs was measured by bioelectrical impedance analysis (BIA), and the phase angle images of the left and right calves were reconstructed using ΦEIT. The relationship between the global average phase angle Φ_M and the spatial average phase angle Φ_Mi of each muscle compartment and fat infiltration was further analyzed. ResultsIn the laboratory pork model, the grayscale value of the image increased with the increase of η_fat and Φ_M showed a downward trend. The results of human experiments showed that at the same fat content percentage, the Φ_M of the 26-30-year-old group was about 20%-35% lower than that of the 20-25-year-old group. The fat content percentage was significantly negatively correlated with Φ_M. In addition, the M₂ (soleus) compartment was most sensitive to fat infiltration, and the spatial average phase angles of the M₂ (soleus), M₃ (tibialis posterior and flexor digitorum longus), and M₄ (tibialis anterior, extensor digitorum longus, and peroneus longus) compartments all showed significant inter-group differences. ConclusionΦEIT imaging can effectively distinguish different degrees of fat infiltration, especially in deep, small or specially located muscles, showing high sensitivity, demonstrating the potential application of this method in local muscle mass monitoring and early non-invasive diagnosis.

Objective: To investigate the clinical characteristics of induced labor in twin pregnancy and the related factors of induced labor failure. Methods: The clinical data of twin pregnant women who underwent induced labor in Peking University Third Hospital from January 2016 to December 2022 were retrospectively analyzed. According to whether they had labor or not after induction, pregnant women were divided into the success group (pregnant women who had labor after induction, 72 cases) and the failure group (pregnant women who did not have labor after induction, 30 cases). Logistic regression was used to analyze the related factors of induction failure in twin pregnant women. Results: The parity and cervical Bishop score in the failure group were significantly lower than those in the success group, while the proportion of dichorionic diamniotic twins, assisted reproductive technology pregnancy and cervical Bishop score <6, postpartum hospital stay and total hospital stay in the failure group were significantly higher than those in the success group (all P<0.05). The proportion of induced labor by artificial rupture of membranes ± oxytocin intravenous infusion in the success group was 72.2% (52/72), which was significantly higher than that in the failure group (46.7%, 14/30; P=0.030). There were no significant differences between the two groups in the gestational age at delivery, the incidence of severe postpartum hemorrhage and blood transfusion, the amount of postpartum hemorrhage, the neonatal weight of two fetuses, the incidence of neonatal asphyxia, and the proportion of neonates admitted to the neonatal intensive care unit (all P>0.05). There were no severe perineal laceration and hysterectomy in all pregnant women. Multivariate logistic regression analysis showed that primipara (OR=3.064, 95%CI: 1.112-8.443; P=0.030) and cervical Bishop score <6 (OR=5.208, 95%CI: 2.008-13.508; P=0.001) were the independent risk factors for induction failure in twin pregnancy. Conclusions: Elective induction of labor in twin pregnancy is safe and feasible. It is helpful to improve the success rate of induction of labor by strictly grasping the timing and indications of termination of pregnancy, choosing the appropriate method of induction according to the condition of the cervix, and actively promoting cervical ripening .
Infant, Newborn ; Pregnancy ; Female ; Humans ; Pregnancy Trimester, Third ; Pregnancy, Twin ; Postpartum Hemorrhage/etiology* ; Retrospective Studies ; Labor, Induced/methods* ; Cervical Ripening

Objective To establish and validate a method for the detection of isavuconazole in human plasma by ultra-performance liquid chromatography-mass spectrometry,and apply to blood concentration monitoring to optimize drug treatment regimens.Methods The proteins in plasma samples were precipitated with acetonitrile;isavuconazole-D4 was used as the internal standard.Chromatographic column was ACQUITY UPLC BEH C18(2.1 mm × 50 mnm,1.7 μm),flow phase was 2 mmol·L-1 ammonium acetate-water(containing 0.1％formic acid,A),acetonitrile(containing 0.1％formic acid,B),flow rate was 0.2 mL·min-1,and the column temperature was 40 ℃.Injection volume was 1 μL.The ion pairs were quantitatively analyzed by electro-spray ionization positive ion mode and multiple reaction monitoring,m/z 438.30 → 224.15(isavuconazole),m/z 442.10 → 224.10(isavuconazole-D4).Results The linear range of isavuconazole was 0.31 to 40.00 μg·mL-1(R2=0.999 4);lower limit of quantification(LLOQ)was 0.31 μg·mL-1.The intra-day and inter-day precision ranged from 2.03％to 12.97％and 4.32％to 9.63％,the accuracy deviation ranged from 89.82％to 110.72％and 95.45％to 100.13％,the extraction recovery rates of low,medium and high concentrations ranged from 94.31％to 100.23％.The results of the blood concentrations of 14 patients with clinical use of isavuconazole measured by this method showed that all patients achieved the effective therapeutic concentration of isavuconazole(＞1-2 μg·mL-1).Conclusion This method is fast,sensitive,accurate and stable,It is suitable for detecting the blood concentration of clinical isavuconazole and providing technical guidance for the adjustment of treatment regimen.

Objective:To assess the effectiveness of a 6-month Ba Duan Jin exercise program in improving the balance of community-dwelling older adults.Methods:A two arms, parallel-group, cluster randomized controlled trial was conducted in 1 028 community residents aged 60-80 years in 40 communities in 5 provinces of China. Participants in the intervention group (20 communities, 523 people) received Ba Duan Jin exercise 5 days/week, 1 hour/day for 6 months, and three times of falls prevention health education, and the control group (20 communities, 505 people) received falls prevention health education same as the intervention group. The Berg balance scale (BBS) score was the leading outcome indicator, and the secondary outcome indicators included the length of time of standing on one foot (with eyes open and closed), standing in a tandem stance (with eyes open and closed), the closed circle test, and the timed up to test.Results:A total of 1 028 participants were included in the final analysis, including 731 women (71.11%) and 297 men (28.89%), and the age was (69.87±5.67) years. After the 3-month intervention, compared with the baseline data, the BBS score of the intervention group was significantly higher than the control group by 3.05 (95% CI: 2.23-3.88) points ( P<0.001). After the 6-month intervention, compared with the baseline data, the BBS score of the intervention group was significantly higher than the control group by 4.70 (95% CI: 4.03-5.37) points ( P<0.001). Ba Duan Jin showed significant improvement ( P<0.05) in all secondary outcomes after 6 months of exercise in the intervention group compared with the control group. Conclusions:This study showed that Ba Duan Jin exercise can improve balance in community-dwelling older adults aged 60-80. The longer the exercise time, the better the improvement.

Objective:To report the results of national surveillance on the distribution and antimicrobial resistance profile of clinical Gram-negative bacteria isolates from bloodstream infections in China in 2022.Methods:The clinical isolates of Gram-negative bacteria from blood cultures in member hospitals of national bloodstream infection Bacterial Resistant Investigation Collaborative System（BRICS）were collected during January 2022 to December 2022. Antibiotic susceptibility tests were conducted by agar dilution or broth dilution methods recommended by Clinical and Laboratory Standards Institute（CLSI）. WHONET 5.6 and SPSS 25.0 software were used to analyze the data.Results:During the study period，9 035 strains of Gram-negative bacteria were collected from 51 hospitals，of which 7 895（87.4%）were Enterobacteriaceae and 1 140（12.6%）were non-fermenting bacteria. The top 5 bacterial species were Escherichia coli（ n=4 510，49.9%）， Klebsiella pneumoniae（ n=2 340，25.9%）， Pseudomonas aeruginosa（ n=534，5.9%）， Acinetobacter baumannii complex（ n=405，4.5%）and Enterobacter cloacae（ n=327，3.6%）. The ESBLs-producing rates in Escherichia coli， Klebsiella pneumoniae and Proteus spp. were 47.1%（2 095/4 452），21.0%（427/2 033）and 41.1%（58/141），respectively. The prevalence of carbapenem-resistant Escherichia coli（CREC）and carbapenem-resistant Klebsiella pneumoniae（CRKP）were 1.3%（58/4 510）and 13.1%（307/2 340）；62.1%（36/58）and 9.8%（30/307）of CREC and CRKP were resistant to ceftazidime/avibactam combination，respectively. The prevalence of carbapenem-resistant Acinetobacter baumannii（CRAB）complex was 59.5%（241/405），while less than 5% of Acinetobacter baumannii complex was resistant to tigecycline and polymyxin B. The prevalence of carbapenem-resistant Pseudomonas aeruginosa（CRPA）was 18.4%（98/534）. There were differences in the composition ratio of Gram-negative bacteria in bloodstream infections and the prevalence of main Gram-negative bacteria resistance among different regions，with statistically significant differences in the prevalence of CRKP and CRPA（ χ2=20.489 and 20.252， P<0.001）. The prevalence of CREC，CRKP，CRPA，CRAB，ESBLs-producing Escherichia coli and Klebsiella pneumoniae were higher in provinicial hospitals than those in municipal hospitals（ χ2=11.953，81.183，10.404，5.915，12.415 and 6.459， P<0.01 or <0.05），while the prevalence of CRPA was higher in economically developed regions（per capita GDP ≥ 92 059 Yuan）than that in economically less-developed regions（per capita GDP <92 059 Yuan）（ χ2=6.240， P=0.012）. Conclusions:The proportion of Gram-negative bacteria in bloodstream infections shows an increasing trend，and Escherichia coli is ranked in the top，while the trend of CRKP decreases continuously with time. Decreasing trends are noted in ESBLs-producing Escherichia coli and Klebsiella pneumoniae. Low prevalence of carbapenem resistance in Escherichia coli and high prevalence in CRAB complex have been observed. The composition ratio and antibacterial spectrum of bloodstream infections in different regions of China are slightly different，and the proportion of main drug resistant bacteria in provincial hospitals is higher than those in municipal hospitals.

Objective:To report the results of national surveillance on the distribution and antimicrobial resistance profile of clinical Gram-positive bacteria isolates from bloodstream infections in China in 2022.Methods:The clinical isolates of Gram-positive bacteria from blood cultures in member hospitals of National Bloodstream Infection Bacterial Resistant Investigation Collaborative System（BRICS）were collected during January 2022 to December 2022. Antibiotic susceptibility tests were conducted by agar dilution or broth dilution methods recommended by Clinical and Laboratory Standards Institute（CLSI）. WHONET 5.6 and SPSS 25.0 software were used to analyze the data.Results:A total of 3 163 strains of Gram-positive pathogens were collected from 51 member units，and the top five bacteria were Staphylococcus aureus（ n=1 147，36.3%），coagulase-negative Staphylococci（ n=928，29.3%）， Enterococcus faecalis（ n=369，11.7%）， Enterococcus faecium（ n=296，9.4%）and alpha-hemolyticus Streptococci（ n=192，6.1%）. The detection rates of methicillin-resistant Staphylococcus aureus（MRSA）and methicillin-resistant coagulase-negative Staphylococci（MRCNS）were 26.4%（303/1 147）and 66.7%（619/928），respectively. No glycopeptide and daptomycin-resistant Staphylococci were detected. The sensitivity rates of Staphylococcus aureus to cefpirome，rifampin，compound sulfamethoxazole，linezolid，minocycline and tigecycline were all >95.0%. Enterococcus faecium was more prevalent than Enterococcus faecalis. The resistance rates of Enterococcus faecium to vancomycin and teicoplanin were both 0.5%（2/369），and no vancomycin-resistant Enterococcus faecium was detected. The detection rate of MRSA in southern China was significantly lower than that in other regions（ χ2=14.578， P=0.002），while the detection rate of MRCNS in northern China was significantly higher than that in other regions（ χ2=15.195， P=0.002）. The detection rates of MRSA and MRCNS in provincial hospitals were higher than those in municipal hospitals（ χ2=13.519 and 12.136， P<0.001）. The detection rates of MRSA and MRCNS in economically more advanced regions（per capita GDP≥92 059 Yuan in 2022）were higher than those in economically less advanced regions（per capita GDP<92 059 Yuan）（ χ2=9.969 and 7.606， P=0.002和0.006）. Conclusions:Among the Gram-positive pathogens causing bloodstream infections in China， Staphylococci is the most common while the MRSA incidence decreases continuously with time；the detection rate of Enterococcus faecium exceeds that of Enterococcus faecalis. The overall prevalence of vancomycin-resistant Enterococci is still at a low level. The composition ratio of Gram-positive pathogens and resistant profiles varies slightly across regions of China，with the prevalence of MRSA and MRCNS being more pronounced in provincial hospitals and areas with a per capita GDP≥92 059 yuan.

Objective To investigate the feasibility of establishing an animal model of rectovaginal fistula in rabbits by magnetic compression technique.Methods A magnetic device suitable for preparing rabbit rectovaginal fistula model was self-designed.Eight New Zealand female rabbits were used as experimental subjects.They were placed in a supine position after auricular intravenous anesthesia,and the magnets were placed on both sides of the rectovaginal septum through the vagina and anus,respectively,and the magnets were made to attract together.The operation time was recorded,the general state of the experimental rabbits was observed after operation,and the time of magnet discharge was recorded.The experimental rabbits were killed 1 week after operation to obtain rectovaginal fistula specimens,and the formation of rectovaginal fistula was observed by naked eye.Results The animal model of rectovaginal fistula was successfully established in 8 experimental rabbits.The operation process was smooth,with an average time of(1.63±0.70)minutes.The rabbits were generally in good condition after operation.The magnet was discharged from the body at(4.63±0.99)day after operation,and the rectovaginal fistula specimens were obtained 1 week after operation,and the rectovaginal fistula was well formed by naked eye observation.Conclusion The establishment of rabbit rectovaginal fistula model by magnetic compression technique has the advantages of simple operation and high success rate of model preparation.

Objective:To investigate the correlation between morphological typing and monoclonality of bone marrow plasma cells,and explore the diagnostic value of plasma cell morphological typing for high-risk smoldering multiple myeloma(HR-SMM).Methods:The correlation between the morphological characteristics and the monoclonality of bone marrow plasma cells was analyzed in 84 patients with HR-SMM who treated in our hospital.The consistency of morphologically abnormal bone marrow plasma cells with serum free light chain(sFLC)ratio,next-generation sequencing(NGS)detection results,and its correlation with monoclonal plasma cells detected by flow cytometry(FCM)were further verified.The immunoglobulin types and levels of non-involved immunoglobulins in serum of the patients were detected,and the distribution of plasma cell clusters in patients with different disease was observed.Results:The mean percentage of mature plasma cells were decreased successively in the order of reactive plasmacytosis(RP)group,monoclonal gammopathy of undetermined significance(MGUS)group,smoldering multiple myeloma(SMM)group,HR-SMM group and multiple myeloma(MM)group;while the mean percentage of immature,primitive,reticular and flaming plasma cells were increased successively in the order of RP group,MGUS group,SMM group,and HR-SMM group,and the difference between any two groups was statistically significant(P＜0.05).The average proportion of abnormal plasma cells in the bone marrow of HR-SMM patients was 96.2％of the total plasma cells.The proportion of abnormal plasma cells were in good agreement with the sFLC ratio and the results of NGS detection in HR-SMM patients(kappa=0.879 and kappa=0.891,both＞0.75),and showed good correlation with the monoclonal plasma cells with immunophenotype of CD45-/CD38+/CD138+/CD56+/CD19-(γ=0.825).The levels of non-involved immunoglobulin in IgG,IgA and IgM type HR-SMM patients were all decreased by more than 25％compared with the normal reference range,and the differences were statistically significant(P＜0.05).There was no significant difference in the distribution ratio of plasma cell clusters among different disease groups(P＞0.05).Conclusion:In HR-SMM patients,the immature,primitive,reticular and flaming plasma cells in bone marrow are considered as abnormal plasma cells,and they are correlated with monoclonal plasma cells.The proportion of abnormal plasma cells in total plasma cells of bone marrow and the reduction extent of non-involved immunoglobulin level in patients have certain reference value for the diagnosis of HR-SMM.

Objective:To investigate the effect of genetic polymorphism of MTHFR C677T (rs1801133) on methotrexate (MTX) related toxicity in pediatric mature B-cell lymphoma patients. Methods:Fifty-eight intermediate and high risk patients under 18 years of age with mature B-cell lymphoma who received 5 g/m2 MTX (24 h intravenous infusion) in Sun Yat-sen University Cancer Center from August 2014 to December 2021 were included,and their toxicity of high-dose MTX (HD-MTX) were monitored and analyzed. Results:Among the 58 pediatric patients,the number of CC,CT,and TT genotypes for MTHFR C677T was 33,19 and 6,respectively. A total of 101 courses of HD-MTX therapy were counted,of which plasma MTX level>0.2 μmol/L at 48 h post-MTX infusion were observed in 35 courses,≤0.2 μmol/L in 66 courses. Inter-group comparison showed that plasma MTX level>0.2 μmol/L at 48 h post-MTX infusion increased the risk of developing oral mucositis (P<0.05). Compared with wild-type (CC genotype),patients in the mutant group (CT+TT genotype) were more likely to develop myelosuppression,manifested as anemia,leucopenia,neutropenia and thrombocytopenia. However,plasma MTX level at 48 h was not associated with MTHFR C677T gene polymorphism. Conclusion:The risk of developing oral mucositis in children with mature B-cell lymphoma is associated with plasma MTX concentration. Polymorphism of MTHFR C677T gene is not related to plasma MTX concentration in children with mature B-cell lymphoma,but is related to grade Ⅲ to Ⅳ hematological toxicity.