1.Characteristics of diaphragmatic function in stroke patients based on ultrasound
Guixiang SHAN ; Jubao DU ; Lei CAO ; Linlin YE ; Chunjing JIANG ; Ye ZHANG ; Huijuan MA ; Weiqun SONG
Chinese Journal of Rehabilitation Theory and Practice 2026;32(7):760-767
ObjectiveTo evaluate the impact of stroke on diaphragmatic function by ultrasound. MethodsFrom April, 2024 to June, 2025, 40 stroke patients (stroke group) were recruited in Xuanwu Hospital Capital Medical University. Additionally, 40 sex- and age-matched healthy subjects (control group) were recruited without directional selection. Diaphragmatic excursion and diaphragmatic thickness during quiet breathing and deep breathing were assessed using ultrasound in both groups, and the diaphragmatic thickening fraction was calculated. The stroke group was further divided into two subgroups according to disease course: ≤ 30 days group and > 30 days group, for subgroup analysis. ResultsDuring both quiet and deep breathing, diaphragmatic excursion on the affected side in the stroke group was smaller than that on the unaffected side and in the control group (P < 0.05). During quiet breathing, diaphragmatic thickening fraction on the affected side in the stroke group was smaller than that on the unaffected side and in the control group (P < 0.05), while the diaphragmatic thickening fraction on the unaffected side was significantly smaller than that in the control group (P < 0.01). During deep breathing, the bilateral diaphragmatic thickening fraction in the stroke group was significantly smaller than that in the control group (P < 0.001), and the bilateral end-inspiratory diaphragmatic thickness was significantly smaller than that in the control group (P < 0.001). During quiet breathing, diaphragmatic excursion in both the ≤ 30 d group and the > 30 d group was smaller than that in the control group (P < 0.05); during deep breathing, diaphragmatic excursion in the ≤ 30 d group was smaller than that in the control group (P < 0.05). In both quiet breathing and deep breathing, the diaphragmatic thickening fraction in the ≤ 30 d group and the >30 d group were lower than those in the control group (P < 0.05). During deep breathing, end-inspiratory diaphragmatic thickness in both the ≤ 30 d group and the > 30 d group was significantly smaller than that in the control group (P < 0.01). ConclusionUltrasound can effectively identify the impact of stroke on patients' diaphragmatic function. In stroke patients, both diaphragmatic excursion and contractile performance are reduced on the affected side, while contractile performance is also reduced on the unaffected side.
2.Effects of knee extension constraint training on knee biomechanics and bilateral symmetry during running after ACL reconstruction
Shengxing FU ; Huijuan SHI ; Yuanyuan YU ; Mujia MA ; Yulin ZHOU ; Hongshi HUANG ; Yingfang AO ; Hui LIU
Chinese Journal of Sports Medicine 2025;44(2):95-102
Objective To determine the effect of knee extension constraint training on bilateral knee biomechanics and bilateral symmetry in running after anterior cruciate ligament reconstruction(ACLR).Methods A total of 33 male patients with unilateral ACL injuries were randomly assigned to a BRACE group of 14 wearing a brace with limitation of knee extension,a PLACEBO group of 10 wear-ing a brace without limitation of knee extension,and a CONTROL group of 9,wearing no brace.All groups underwent unilateral hamstring-auto graft ACLR surgery,immediately followed by 12-week rou-tine rehabilitation.Between week 13 and 48,both the BRACE and PLACEBO groups wore braces for one hour on Mondays.Then,running biomechanical tests were performed at the ends of Week 12 and Week 48,and the bilateral knee extension/flexion angle,moment and inter-leg difference(ILD)were calculated.One-dimensional statistical parametric mapping(SPM1d)two-way ANOVA with repeated measures on one factor was used to identify differences in bilateral knee biomechanics and ILD among the three groups before and after the intervention.Results There was no significant interaction effect of group and time on bilateral knee flexion angle,knee extension moment,and ILD in running(P>0.05).Moreover,no significant effect of group was found on the bilateral knee biomechanics and ILD in running(P>0.05).Additionally,significant effects of time were observed on bilateral knee flexion angle and extension moment in running.However,bilateral knee flexion angle decreased during termi-nal stance(ACLR leg:89%~100%,P=0.036;non-ACLR leg:94%~100%,P=0.046),while the bi-lateral knee extension moment increased during mid-stance(ACLR leg:17%~59%,P<0.001;non-ACLR leg:38%~61%,P<0.001)between week 12 and 48.Conclusion In this study,no improvement was found in the abnormal knee biomechanics and symmetry during running in male patients after uni-lateral ACL reconstruction through long-term knee extension constraint training.Moreover,within one year after ACL reconstruction,the knee extension moment of the surgical limb increased gradually over time,with no changes in the knee flexion angle of the surgical limb and bilateral knee symme-try,suggesting that abnormal knee biomechanics and bilateral symmetry should be paid attention to in the post-surgery rehabilitation.
3.Cancer Incidence and Mortality in Liaoning Cancer Regi-stration Areas from 2016 to 2020 and Trends from 2006 to 2020
Huijuan MU ; Yanxia LI ; Xiang MA ; Jun NA ; Liya YU ; Jiang TIAN ; Li LIU
China Cancer 2025;34(4):279-289
[Purpose]To analyze cancer incidence and mortality in Liaoning cancer registration areas from 2016 to 2020 and the trends from 2006 to 2020.[Methods]Cancer data in cancer registra-tion areas in Liaoning Province from 2016 to 2020 were collected.The incidence and mortality,age-standardized rate,cumulative rate(0~74 years old),and age-specific rate were calculated.Age-standardized incidence and mortality rate were calculated by the Chinese standard popula-tion(ASIRC,ASMRC)and Segi world standard population(ASIRW,ASMRW).Joinpoint software was applied to analyze the trends of incidence and mortality.[Results]From 2016 to 2020,the crude incidence rate of cancer in Liaoning cancer registration areas was 422.30/105,the ASIRC and ASIRW were 215.67/105 and 209.52/105.The ASIRC was higher in urban areas(225.00/105)than that in rural areas(190.15/105),and higher in male(221.47/105)than that in female(213.03/105).The crude mortality rate was 254.22/105,the ASMRC and ASMRW were 113.26/105 and 112.91/105.The ASMRC in urban areas(113.12/105)was the same as that in rural areas(113.01/105),and higher in male(146.86/105)than that in female(83.46/105).The ASIRW of lung cancer was 46.13/105,and the ASMRW was 32.04/105,both ranking the first of all cancers.From 2006 to 2020,the crude incidence,ASIRC and ASIRW in urban areas showed an increasing trend(AAPC=3.921%,t=16.222,P<0.05;AAPC=0.823%,t=2.409,P<0.05;AAPC=0.875%,t=2.933,P<0.05).The crude incidence,ASIRC and ASIRW in urban female were all rising(AAPC=4.151%,t=15.888,P<0.05;AAPC=1.597%,t=4.819,P<0.05;AAPC=1.514%,t=4.752,P<0.05).During the same period,the cancer mortality in urban areas showed an increasing trend(AAPC=3.175%,t=14.745,P<0.05),and the ASMRW showed a decreasing trend(AAPC=-0.908%,t=-2.273,P<0.05).The crude mor-tality of both men and women showed an increasing trend(AAPC=3.010%,t=6.032,P<0.05;AAPC=2.820%,t=5.921,P<0.05),while the crude mortality and ASMRW for female showed a significant downward trend(AAPC=-1.487%,t=-2.437,P<0.05;AAPC=-2.680%,t=-2.246,P<0.05).From 2016 to 2020,the crude incidence,ASIRC and ASIRW in rural areas showed no significant change;however,the crude incidence in male was increasing(AAPC=2.025%,t=3.853,P<0.05).In the same period,the crude mortality rate in rural areas increased(AAPC=3.577%,t=9.377,P<0.05),while there was no significant change in the ASMRC and ASMRW.The crude mortality of both men and women showed an increasing trend(AAPC=3.377%,t=10.615,P<0.05;AAPC=3.978%,t=7.245,P<0.05),while there was no significant change in ASMRC and ASMRW.[Conclusion]The cancer burden in Liaoning from 2016 to 2020 was higher than the average level in China,can-cer prevention and control should be further strengthened in the provice.
4.Effects of knee extension constraint training on knee biomechanics and bilateral symmetry during running after ACL reconstruction
Shengxing FU ; Huijuan SHI ; Yuanyuan YU ; Mujia MA ; Yulin ZHOU ; Hongshi HUANG ; Yingfang AO ; Hui LIU
Chinese Journal of Sports Medicine 2025;44(2):95-102
Objective To determine the effect of knee extension constraint training on bilateral knee biomechanics and bilateral symmetry in running after anterior cruciate ligament reconstruction(ACLR).Methods A total of 33 male patients with unilateral ACL injuries were randomly assigned to a BRACE group of 14 wearing a brace with limitation of knee extension,a PLACEBO group of 10 wear-ing a brace without limitation of knee extension,and a CONTROL group of 9,wearing no brace.All groups underwent unilateral hamstring-auto graft ACLR surgery,immediately followed by 12-week rou-tine rehabilitation.Between week 13 and 48,both the BRACE and PLACEBO groups wore braces for one hour on Mondays.Then,running biomechanical tests were performed at the ends of Week 12 and Week 48,and the bilateral knee extension/flexion angle,moment and inter-leg difference(ILD)were calculated.One-dimensional statistical parametric mapping(SPM1d)two-way ANOVA with repeated measures on one factor was used to identify differences in bilateral knee biomechanics and ILD among the three groups before and after the intervention.Results There was no significant interaction effect of group and time on bilateral knee flexion angle,knee extension moment,and ILD in running(P>0.05).Moreover,no significant effect of group was found on the bilateral knee biomechanics and ILD in running(P>0.05).Additionally,significant effects of time were observed on bilateral knee flexion angle and extension moment in running.However,bilateral knee flexion angle decreased during termi-nal stance(ACLR leg:89%~100%,P=0.036;non-ACLR leg:94%~100%,P=0.046),while the bi-lateral knee extension moment increased during mid-stance(ACLR leg:17%~59%,P<0.001;non-ACLR leg:38%~61%,P<0.001)between week 12 and 48.Conclusion In this study,no improvement was found in the abnormal knee biomechanics and symmetry during running in male patients after uni-lateral ACL reconstruction through long-term knee extension constraint training.Moreover,within one year after ACL reconstruction,the knee extension moment of the surgical limb increased gradually over time,with no changes in the knee flexion angle of the surgical limb and bilateral knee symme-try,suggesting that abnormal knee biomechanics and bilateral symmetry should be paid attention to in the post-surgery rehabilitation.
5.Clinical and pathological characteristic analysis of diabetic kidney disease with Kimmelstiel-Wilson nodule
Kai CHEN ; Yingying WANG ; Xianmin BU ; Huijuan MA
Chinese Journal of Postgraduates of Medicine 2025;48(5):434-439
Objective:To investigate the correlation between Kimmelstiel-Wilson nodule (KW nodule) and clinical indexes in patients with diabetic kidney disease (DKD), and analyze the efficacy of the clinical indexes in evaluating KW nodule.Methods:The clinical data of 60 patients with DKD from January 2015 to February 2024 in Jining First People′s Hospital were retrospectively analyzed. Among them, 35 patients had KW nodule (KW nodule group), and 25 patients did have KW nodule (non-KW nodule group). The clinical indexes, including hematological (creatinine, uric acid, urea nitrogen, globulin, albumin, glycosylated hemoglobin and hemoglobin) and urine routine (24 h urinary protein quantification, urinary red blood cell count and urinary white blood cell count) were recorded; the estimated glomerular filtration rate (eGFR) was calculated. Spearman correlation was used to analyze the correlation between clinical indexes and KW nodule. Multivariate Logistic regression was used to analyze the independent risk factors for KW nodule in patients with DKD. Receiver operating characteristic (ROC) curve was used to analyze the efficacy of clinical indexes in evaluating KW nodule.Results:The creatinine, urea nitrogen, 24 h urinary protein quantification and urine red blood cell count in KW nodule group were significantly higher than those in non-KW nodule group: 114 (89, 156) μmol/L vs. 70 (59, 87) μmol/L, 9.00 (6.90, 11.43) mmol/L vs. 5.10 (4.52, 7.55) mmol/L, 4.56 (2.36, 7.23) g vs. 1.40 (1.11, 1.97) g and (19.24 ± 12.64)×10 6/L vs. (9.24 ± 8.67)×10 6/L, the eGFR, albumin and hemoglobin were significantly lower than those in non-KW nodule group: (60.82 ± 28.16) ml/(min·1.73 m 2) vs. (98.34 ± 30.16) ml/(min·1.73 m 2), (30.21 ± 6.64) g/L vs. (39.89 ± 6.49) g/L and (107.54 ± 17.28) g/L vs. (136.87 ± 22.90) g/L, and there were statistical differences ( P<0.01); there were no statistical differences in uric acid, globulin, glycosylated hemoglobin and urinary white blood cell count between the two groups ( P>0.05). Spearman correlation analysis result showed that creatinine, urea nitrogen, 24 h urinary protein quantification and urine red blood cell count were positively correlated with KW nodule ( r = 0.471, 0.559, 0.510 and 0.411; P<0.01); the eGFR, albumin and hemoglobin were negatively correlated with KW nodule ( r = - 0.607, - 0.590 and - 0.600; P<0.01). Multivariate Logistic regression analysis result showed that high 24 h urinary protein quantification and low albumin were independent risk factors for KW nodule in patients with DKD ( OR = 3.415 and 0.829, 95% CI 1.002 to 8.956 and 0.690 to 0.995, P<0.05). ROC curve analysis result showed that the areas under the curve of eGFR, hemoglobin, albumin, creatinine, 24 h urinary protein quantification and urine red blood cell count for KW nodule in patients with DKD were 0.852, 0.840, 0.848, 0.836, 0.881 and 0.768, respectively; the optimal cut-off values were 69.00 ml/(min·1.73 m 2), 110.00 g/L, 31.75 g/L, 96.10 μmol/L, 2.60 g and 15.52 × 10 6/L. Conclusions:There is a good correlation between KW nodule and the clinical features of DKD patients. Decreased renal function, anemia, proteinuria and hypoproteinemia have strong suggestive effects on KW nodule. Especially, proteinuria is more closely related.
6.Indole-3-aldehyde-loaded inulin-based hydrogel for protection against radiation-induced intestinal injury
Tuo LI ; Feifei MA ; Jiebing GUAN ; Siyu XIE ; Ning WANG ; Ningning HE ; Huijuan SONG ; Jianguo LI ; Qiang LIU
Chinese Journal of Radiological Medicine and Protection 2025;45(5):408-415
Objective:To explore the protective effects and mechanisms of an indole-3-acetaldehyde (I3A)-loaded inulin-based hydrogel against radiation-induced intestinal injury.Methods:The gelation properties and injectability of the I3A-loaded inulin-based hydrogel were detected using a rheometer, and its biocompatibility was assessed via a CCK-8 assay. Eighteen C57BL/6 mice (aged: 6-8 weeks) were stratified by body weight and randomly assigned into three groups with 6 mice in each group: blank control, irradiation-only, and irradiation+ hydrogel protection. Abdominal irradiation was administered using 137Cs γ-rays at 17 Gy. The irradiation+ hydrogel protection group received 200 μl/day of I3A-loaded inulin-based hydrogel for two days before and 2-3 days after irradiation. Meanwhile, the irradiation-only group was treated with an equivalent volume of sterile water via gavage. The mice were euthanized four days post-irradiation, and their intestinal tissues were harvested. Hematoxylin-eosin (HE) staining, Ki67 immunohistochemistry, and TUNEL immunofluorescence were performed to assess histopathological damage, epithelial cell proliferation, and apoptosis, respectively. Quantitative real-time PCR (qRT-PCR) was employed to measure mRNA levels of inflammatory and antioxidant factors. Gut microbiota composition was analyzed via 16S rRNA sequencing. Results:The test results of the rheometer confirmed successful hydrogel formation. CCK-8 assays demonstrated excellent biocompatibility. Compared with the irradiation-only group, the irradiation+ hydrogel protection group exhibited preserved intestinal histoarchitecture, a 1.5-fold increase in intestinal cell proliferation ( t = 8.35, P < 0.05), and a 2-fold reduction in radiation-induced apoptosis ( t = 7.94, P < 0.05). Moreover, the hydrogel group showed significantly elevated expression of the anti-inflammatory cytokine IL-10 and antioxidant factors NRF-2 and HO-1 ( t = 3.16, 24.83, 5.92, P < 0.05), alongside reduced levels of pro-inflammatory cytokines IL-1β, IL-6, and TNF-α ( t = 5.15, 3.82, 3.83, P < 0.05). Gut microbiota analysis revealed significant modulation in microbial composition and abundance in the hydrogel group. Conclusions:The I3A-loaded inulin-based hydrogel can significantly promote intestinal cell proliferation, reduce radiation-induced apoptosis, and enhance both anti-inflammatory and antioxidant responses. In addition, it regulates gut microbiota composition and abundance, protecting against radiation-induced intestinal injury.
7.Epidemiology and influencing factors of skin complications at the puncture site following femoral artery compression in patients with primary hepatocellular carcinoma after TACE
Xuemin JING ; Ruiying MA ; Lili ZHANG ; Huijuan GE ; Yongmei WANG ; Xiuya XING ; Xia JING ; Li ZHOU ; Cailian WANG ; Wanmiao GUI ; Jingjie REN
Journal of Interventional Radiology 2025;34(8):894-899
Objective To investigate the epidemiological characteristics and influencing factors of Femoral Artery Compression-Related Skin Complications Around the Puncture Site(FACR-SCAPS)in patients with primary hepatocellular carcinoma(HCC)undergoing transarterial chemoembolization(TACE).Methods A multicenter cross-sectional study was conducted using convenience sampling.A total of 1 573 HCC patients who underwent TACE between April 2023 and October 2024 were recruited from interventional radiology departments,oncology units,and specialized centers across 10 hospitals in Beijing,Tianjin,Shandong,Hebei,Qinghai,and Inner Mongolia.Descriptive statistics,univariate analysis,and multivariate logistic regression were used to explore the epidemiological characteristics and influencing factors of FACR-SCAPS in this population.Results Among the 1 573 primary HCC patients undergoing TACE interventional therapy,FACR-SCAPS occurred in 28.99%(456/1 573),with a total of 476 complication instances recorded(30.26 per 100 patients).Patients with a single complication accounted for 96.93%,whereas those with multiple complications constituted 3.07%.The most prevalent types of complications were skin erythema,skin ecchymosis,and hard lumps formation,collectively accounting for 96.49%of all complications.Hematoma,blisters,and rupture complications collectively accounted for only 4.61%.Logistic regression analysis revealed that peak diastolic blood pressure during compression(OR=1.024,95%CI:1.013-1.035,P<0.001),use of rotary compression hemostasis devices(OR=3.220,95%CI:2.120-4.891,P<0.001),elevated PT-INR(OR=19.630,95%CI:6.039-63.810,P<0.001),and anticoagulant use within the last three months(OR=1.909,95%CI:1.064-3.427,P=0.030)were significant influencing factors associated with FACR-SCAPS post-TACE.Conclusion FACR-SCAPS is commonly seen among primary HCC patients after TACE,its risk factors include peak diastolic blood pressure during compression,use of rotary compression devices,elevated PT-INR,and recent anticoagulant use.
8.Clinical and pathological characteristic analysis of diabetic kidney disease with Kimmelstiel-Wilson nodule
Kai CHEN ; Yingying WANG ; Xianmin BU ; Huijuan MA
Chinese Journal of Postgraduates of Medicine 2025;48(5):434-439
Objective:To investigate the correlation between Kimmelstiel-Wilson nodule (KW nodule) and clinical indexes in patients with diabetic kidney disease (DKD), and analyze the efficacy of the clinical indexes in evaluating KW nodule.Methods:The clinical data of 60 patients with DKD from January 2015 to February 2024 in Jining First People′s Hospital were retrospectively analyzed. Among them, 35 patients had KW nodule (KW nodule group), and 25 patients did have KW nodule (non-KW nodule group). The clinical indexes, including hematological (creatinine, uric acid, urea nitrogen, globulin, albumin, glycosylated hemoglobin and hemoglobin) and urine routine (24 h urinary protein quantification, urinary red blood cell count and urinary white blood cell count) were recorded; the estimated glomerular filtration rate (eGFR) was calculated. Spearman correlation was used to analyze the correlation between clinical indexes and KW nodule. Multivariate Logistic regression was used to analyze the independent risk factors for KW nodule in patients with DKD. Receiver operating characteristic (ROC) curve was used to analyze the efficacy of clinical indexes in evaluating KW nodule.Results:The creatinine, urea nitrogen, 24 h urinary protein quantification and urine red blood cell count in KW nodule group were significantly higher than those in non-KW nodule group: 114 (89, 156) μmol/L vs. 70 (59, 87) μmol/L, 9.00 (6.90, 11.43) mmol/L vs. 5.10 (4.52, 7.55) mmol/L, 4.56 (2.36, 7.23) g vs. 1.40 (1.11, 1.97) g and (19.24 ± 12.64)×10 6/L vs. (9.24 ± 8.67)×10 6/L, the eGFR, albumin and hemoglobin were significantly lower than those in non-KW nodule group: (60.82 ± 28.16) ml/(min·1.73 m 2) vs. (98.34 ± 30.16) ml/(min·1.73 m 2), (30.21 ± 6.64) g/L vs. (39.89 ± 6.49) g/L and (107.54 ± 17.28) g/L vs. (136.87 ± 22.90) g/L, and there were statistical differences ( P<0.01); there were no statistical differences in uric acid, globulin, glycosylated hemoglobin and urinary white blood cell count between the two groups ( P>0.05). Spearman correlation analysis result showed that creatinine, urea nitrogen, 24 h urinary protein quantification and urine red blood cell count were positively correlated with KW nodule ( r = 0.471, 0.559, 0.510 and 0.411; P<0.01); the eGFR, albumin and hemoglobin were negatively correlated with KW nodule ( r = - 0.607, - 0.590 and - 0.600; P<0.01). Multivariate Logistic regression analysis result showed that high 24 h urinary protein quantification and low albumin were independent risk factors for KW nodule in patients with DKD ( OR = 3.415 and 0.829, 95% CI 1.002 to 8.956 and 0.690 to 0.995, P<0.05). ROC curve analysis result showed that the areas under the curve of eGFR, hemoglobin, albumin, creatinine, 24 h urinary protein quantification and urine red blood cell count for KW nodule in patients with DKD were 0.852, 0.840, 0.848, 0.836, 0.881 and 0.768, respectively; the optimal cut-off values were 69.00 ml/(min·1.73 m 2), 110.00 g/L, 31.75 g/L, 96.10 μmol/L, 2.60 g and 15.52 × 10 6/L. Conclusions:There is a good correlation between KW nodule and the clinical features of DKD patients. Decreased renal function, anemia, proteinuria and hypoproteinemia have strong suggestive effects on KW nodule. Especially, proteinuria is more closely related.
9.Preliminary Efficacy of Growth Hormone Therapy in Children With Congenital HeartDisease and Short Stature: A Six-case Report and Literature Review
Xi YANG ; Siyu LIANG ; Qianqian LI ; Hanze DU ; Shuaihua SONG ; Yue JIANG ; Huijuan MA ; Shi CHEN ; Hui PAN
Medical Journal of Peking Union Medical College Hospital 2025;16(3):641-646
Congenital heart disease (CHD) is a congenital malformation resulting from abnormal embryonic development of the heart and great vessels, accounting for approximately 25% of all congenital malformations. Children with CHD are often complicated by short stature. Although surgical treatment can improve their growth and development to a certain extent, some children still experience growth retardation after surgery. Recombinant human growth hormone (rhGH) is the main drug for treating short stature, but its efficacy and safety in the treatment of patients with concomitant CHD warrant further investigation. This article reports six cases of children with CHD and short stature who were treated with rhGH. Through a literature review, we summarize and discuss the therapeutic efficacy, follow-up experiences, and adverse reactions of rhGH treatment, aiming to provide references for clinicians in applying rhGH to treat patients with CHD and short stature.
10.Expression and enzymatic characterization of a chitosanase with tolerance to a wide range of pH from Bacillus atrophaeus.
Wenjuan DU ; Awagul TURSUN ; Zhiqin DONG ; Huijuan MA ; Zhenghai MA
Chinese Journal of Biotechnology 2025;41(1):352-362
To screen and identify a chitosanase with high stability, we cloned the chitosanase gene from Bacillus atrophaeus with a high protease yield from the barren saline-alkali soil and expressed this gene in Escherichia coli. The expressed chitosanase of B. atrophaeus (BA-CSN) was purified by nickel-affinity column chromatography. The properties including optimal temperature, optimal pH, substrate specificity, and kinetic parameters of BA-CSN were characterized. The results showed that BA-CSN had the molecular weight of 31.13 kDa, the optimal temperature of 55 ℃, the optimal pH 5.5, and good stability at temperatures below 45 ℃ and pH 4.0-9.0. BA-CSN also had good stability within 4 h of pH 3.0 and 10.0, be activated by K+, Na+, Mn2+, Ca2+, Mg2+, and Co2+, (especially by Mn2+), and be inhibited by Fe3+, Cu2+, and Ag+. BA-CSN showcased the highest relative activity in the hydrolysis of colloidal chitosan, and it had good hydrolysis ability for colloidal chitin. Under the optimal catalytic conditions, BA-CSN demonstrated the Michaelis constant Km and maximum reaction rate Vmax of 9.94 mg/mL and 26.624 μmoL/(mL·min), respectively, for colloidal chitosan. In short, BA-CSN has strong tolerance to acids and alkali, possessing broad industrial application prospects.
Bacillus/genetics*
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Hydrogen-Ion Concentration
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Escherichia coli/metabolism*
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Glycoside Hydrolases/biosynthesis*
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Substrate Specificity
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Enzyme Stability
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Chitosan/metabolism*
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Temperature
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Kinetics
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Cloning, Molecular
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Bacterial Proteins/biosynthesis*
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Recombinant Proteins/genetics*

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