BACKGROUND:The elastic modulus of traditional bone implants is large and does not match the elastic modulus of human bone,which will cause a stress shielding effect and lead to bone resorption.The trabecular scaffold of the triply periodic minimal surface with radial gradient has elastic modulus matching with human cancellous bone,and its yield strength is greater than that of human cortical bone,which provides a new choice for the design of bone scaffold. OBJECTIVE:Triply periodic minimal surface structure with radial gradient was constructed by the implicit surface method.The sample was manufactured by laser selective melting technology,and the quasi-static compression test was carried out to obtain trabecular scaffolds with mechanical properties matching human bones. METHODS:Four types of the trabecular scaffolds of the triply periodic minimal surface with a radial gradient of G,I,P and D were established by the implicit surface method.Samples were manufactured by laser selective melting technology.We observed the surface morphology of the molded sample,evaluated the molding quality,conducted a quasi-static compression test,and evaluated the mechanical properties of the samples. RESULTS AND CONCLUSION:The quasi-static compression test results showed that compared with the four triply periodic minimal surface scaffolds,the platform stress of the G scaffold had less fluctuation and no failure or fracture,indicating that the G scaffold had the best plasticity.The mechanical properties of the G scaffolds with 45%,55%and 65%porosities were analyzed.It was found that the elastic modulus of G scaffolds with 55%porosity was within the range of elastic modulus of human cancellous bone(0.022-3.7 GPa),and the yield strength was close to the maximum yield strength of human cortical bone(187.7-222.3 MPa).In conclusion,G triply periodic minimal surface scaffold with 55%porosity can reduce the stress shielding effect,bear a higher body load,improve the stability of the implant,and prolong the service life of the implant.

Objective This study investigated whether gut microbiota and its metabolites are altered in myasthenia gravis(MG)patients.Methods We collected fresh stool specimens from MG patients and healthy controls.16S rRNA gene sequencing and gas chromatography-mass spectrometry were used to measure abundance of gut microbiota and metabolite levels in two groups,respectively.Clinical data of the subjects were also collected including quantitative MG score(QMGS),MG-activities of daily living(MG-ADL),MG-specific quality-of-life 15(MG-QOL15),manual muscle testing(MMT),and the acetylcholine receptor antibody(AchR-Ab)titers.The correlation between the differential microbiota and the clinical characteristics was investigated.Results A total of 50 MG patients and 15 healthy controls were recruited.Simpson's index was significantly higher in the MG group(0.936±0.041)than in the control group(0.888±0.123).Alpha diversity was significantly decreased in the MG group(t=2.349,P=0.022).There was a significant difference in microbial phenotype between the two groups(R=0.966,P=0.001,Adonis).The results of LEfSe showed that the abundance of Esherichia-Shigella,Succinivibrio,Fusobacterium,and Ruminococcus-gnavus-group were up-regulated while the abundance of Lachnospira,Roseburia,Desulfovibrio,and Coprococcus were down-regulated.The results showed that the metabolites of the MG group were significantly different from those of the control group.There were 28 metabolites up-regulated and 71 metabolites down-regulated in the MG patient group.Kyoto Encyclopedia of Genes and Genomes analyses demonstrated that the majority of metabolic pathways in which differential metabolites were involved were related to amino acid metabolism and nucleotide metabolism.61.2% (30/49)of bacterial amplicon sequence variant(ASV)were significantly associated with multiple metabolites(P<0.001).The relative abundance of Lachnospiraceae in the group with MG was negatively correlated with the QMGS(r=-0.496,P<0.001),MG-ADL(r=-0.542,P<0.001),MG-QOL15(r=-0.464,P=0.007),and the AchR-Ab(r=-0.315,P=0.026).The relative abundance of Lachnospiraceae in the group with MG was positively correlated with the MMT(r=0.374,P=0.008).Conclusion The intestinal flora of MG patients is down-regulated in the abundance of beneficial bacteria and up-regulated in the abundances of harmful bacteria.Disturbance of metabolites are also present in MG patients.Regulating gut microbiota in MG patients may be a new target for treating the disease.

Objective: To observe the effects of electroacupuncture (EA) at Neiguan (PC6) on arrhythmia during acute myocardial ischemia-reperfusion and the expression of connexin 43 (Cx43) in rats. Methods: A total of 40 Sprague-Dawley male rats were used. Ten rats were randomly selected as the blank group, and the remaining 30 rats were randomly divided into a model group and an EA group, with 15 rats in each group. Before modeling, rats in the EA group received one session of EA intervention at bilateral Neiguan (PC6) for 30 min; the other groups were treated with the same grasping and anesthesia for 30 min without intervention. PowerLab physiological recorder was used to record electrocardiograph within 30 min of infarction. After the experiment, cardiac tissue and serum were collected from rats. Hematoxylin-eosin (HE) staining was used to observe the morphological changes of myocardial tissue in the ventricular infarction area of rats in each group. The expression of Cx43 protein in the myocardium of each group was detected by Western blotting (WB). Enzyme-linked immunosorbent assay (ELISA) was used to determine the activity of Na+-K+-ATPase in myocardial tissue and the serum content of endogenous digitalis-like factor (EDLF) in rats. Results: There was no statistical difference in arrhythmia score between the EA group and the model group, but the total duration and average duration of arrhythmia in the EA group were decreased (P<0.01). HE staining showed that compared with the blank group, myocardial cells in the model group were disorganized and seriously damaged. The pathological changes in the EA group were similar to those in the model group, but the damage was relatively minor. The results of WB showed that compared with the blank group, the Cx43 expression in myocardial tissue of the model group was decreased (P<0.01); compared with the model group, the Cx43 expression in the EA group was increased (P<0.01); compared with the blank group, the Na+-K+-ATPase activity in myocardial tissue of the model group was significantly decreased (P<0.01); compared with the model group, the Na+-K+-ATPase activity in the EA group was increased (P<0.01). ELISA results showed that compared with the blank group, the serum EDLF content in the model group was significantly increased (P<0.01); compared with the model group, the EDLF content in the EA group was decreased (P<0.01). Conclusion: EA at Neiguan (PC6) can delay and reduce the onset of arrhythmia during myocardial infarction in the rat model of myocardial ischemia-reperfusion. Its mechanism of action may be related to the regulation of the Cx43 expression in myocardial tissue, improvement of the activity of Na+-K+-ATPase in myocardial tissue, and increase in the content of serum EDLF.

Objective:To evaluate the acute effects of different foot-strike patterns of running on knee cartilage in amateur marathon runners using the T 2* mapping technique. Methods:From November 2021 to February 2022, 29 amateur marathon runners were recruited in Hangzhou. The gait analysis was performed to determine their landing patterns, then the runners were divided into the fore-foot strike (FFS) group (11 cases) and the rear-foot strike (RFS) group (18 cases). The MRI of the knee joint of the dominant leg was performed before and 30 min after running, and the volume, thickness, and T 2* value of each division of knee cartilage were measured. Independent samples t-tests were used to compare the differences in baseline data before running between the groups, and paired samples t-tests were used to compare the differences before and after running within the groups. Results:The difference in knee cartilage volume and thickness between the FFS and RFS groups before running was not statistically significant ( P>0.05), and the T 2* value of the femur medial posterior in the RFS group was higher than that of the FFS group ( t=-2.47, P=0.020). Compared with pre-running, cartilage thickness of the tibia lateral posterior decreased in the FFS group after running ( t=-2.96, P=0.016), and cartilage thickness of the tibia lateral posterior and patella lateral central decreased in the RFS group ( t=-3.25, -3.02, P=0.004, 0.007). Cartilage volume of the tibia lateral posterior decreased in the FFS group after running ( t=-2.58, P=0.030), and the cartilage volume of the patella lateral central decreased in the RFS group ( t=-2.74, P=0.013). The differences in T 2* values of cartilage in each region before and after running were not statistically significant in the FFS group ( P>0.05), whereas in the RFS group, the cartilage T 2* values in the femur medial posterior, femoral trochanter central, femoral trochanter lateral, femur lateral central, tibia lateral anterior, tibia medial posterior, tibia medial central, and tibia medial anterior decreased ( P<0.05). Conclusions:After running, FFS showed changes in morphology and biochemical composition only in some subregions of tibial cartilage, whereas most of the femoral cartilage, patellar cartilage, and tibial cartilage regions were altered by RFS. The RFS pattern introduces greater acute changes in cartilage in the knee joint.

Glycosite-specific antibody‒drug conjugatess (gsADCs), harnessing Asn297 N-glycan of IgG Fc as the conjugation site for drug payloads, usually require multi-step glycoengineering with two or more enzymes, which limits the substrate diversification and complicates the preparation process. Herein, we report a series of novel disaccharide-based substrates, which reprogram the IgG glycoengineering to one-step synthesis of gsADCs, catalyzed by an endo-N-acetylglucosaminidase (ENGase) of Endo-S2. IgG glycoengineering via ENGases usually has two steps: deglycosylation by wild-type (WT) ENGases and transglycosylation by mutated ENGases. But in the current method, we have found that disaccharide LacNAc oxazoline can be efficiently assembled onto IgG by WT Endo-S2 without hydrolysis of the product, which enables the one-step glycoengineering directly from native antibodies. Further studies on substrate specificity revealed that this approach has excellent tolerance on various modification of 6-Gal motif of LacNAc. Within 1 h, one-step synthesis of gsADC was achieved using the LacNAc-toxin substrates including structures free of bioorthogonal groups. These gsADCs demonstrated good homogeneity, buffer stability, in vitro and in vivo anti-tumor activity. This work presents a novel strategy using LacNAc-based substrates to reprogram the multi-step IgG glycoengineering to a one-step manner for highly efficient synthesis of gsADCs.

Objective:To explore the effect of implementing group empowerment management model based on Myers-Briggs Type Indicator (MBTI) Scale on the quality of orthopedic nursing management.Methods:From January 2018 to December 2019, MBTI Scale was used to test the personality types of 46 nurses in Department of Orthopedics in Zhejiang Hospital. Test results were analyzed and nurses were grouped and given empowerment management measures. Score of orthopedic nurses on the leaders, score of psychological empowerment of nurses and score of nursing quality were compared before and after the improvement of management.Results:MBTI Scale was used to classify personality types of 46 orthopedic nurses, among which ISFJ, ISTJ, ENFP and ESFJ were the most common personality types. After the implementation of empowerment management, score of nurses on the leaders, score of psychological empowerment of nurses and score of nursing quality were all improved than before, and the differences were statistically significant ( P<0.05) . Conclusions:Based on MBTI Scale, the group empowerment management of orthopedic nurses can give full play to the core advantages of nurses, improve self-management ability of nurses and nursing quality.

Objective:To gain insight into the constitution of juvenile rheumatic diseases, treatment outcome and trends of rheumatic inpatients in past 12 years, and to improve awareness of juvenile rheumatic diseases.Methods:The clinical data of 5 950 patients in rheumatology department of the affiliated pediatric hospital of Fudan University (from 2005 to 2016) were analyzed retrospectively, and the chi-square test was used to compare and analyze the incidence.Results:Disease changes: ① The top three rheumatic diseases were Kawasaki disease (KD) (44.3%), Henoch-schoniein purpura (HSP) (35.4%), juvenile idiopathic arthritis (JIA)(9.6%). ② The number of all constitution of juvenile rheumatic diseases in hospital increased other than HSP. ③ The rheumatic diseases were increased from 17 to 37 kinds in the past 6 years. ④ The number of systemic lupus erythematosus (SLE) increased year by year (112/2 348 vs 197/3 602, χ2=1.41, P=0.235), as well as the severe SLE (35/112 vs 55/197, χ2=0.38, P=0.536). ⑤ The rate of rheumatic diseases complicated with macrophage activation (MAS) was 7.2‰(43/5 950). 12.9%(26/201) of systemic juvenile idiopathic arthritis(sJIA) were complicated with MAS, which was accounted for 60.5%(26/43) of total number of MAS in rheumatic diseases. In the last 6 years, there was a significant increase in the number of patients with MAS in patients with rheumatic diseases ( χ2=14.1, P<0.01) and sJIA( χ2=11.2, P<0.01). ⑥ 1.1%(64/5 950) of rheumatic diseases patients had lung lesions, juvenile dermatomyositis (JDM) accounted for 24.4%(20/82). In the last 6 years, the number of patients with lung lesions associated with rheumatic diseases increased significantly ( χ2=5.66, P=0.017). ⑦ The mortality rate of juvenile rheumatic diseases was only 3.7‰(22/5 950), and 45.5% occurred in SLE (10/22). The mortality rate of SLE decreased in last 6 years (5/112 vs 5/197, χ2=0.34, P=0.558). Conclusion:The constitution of juvenile rheumatic diseases in our center is decreasing for systemic vasculitis (KD, HSP), JIA, SLE, JDM in last 6 years. The annual total number of patients is relatively stable. But rare, difficult and critically illed cases increase year by year. Although SLE is still the primary cause of death in juvenile rheumatic diseases in recent 6 years, the mortality rate has decreased year by year.

Objective: To study the effects of half marathon loading on the T₂* mapping assessment of knee joint cartilage. Methods: Twenty male amateur marathon runners with more than three years of running age were enrolled. The T₁WI, PDWI, 3D-DESS, and T₂* mapping were performed on right knee joint before and after the half marathon within 3h and after a period of approximately 1 week. Cartilage was divided into 6 regions: medial and lateral femoral cartilage, medial and lateral tibial cartilage and patella and trochlea cartilage. Femoral cartilage was partitioned into central weight-bearing regions, posterior cartilage nonweight-bearing regions with the posterior boundary of the meniscus as the dividing mark. All cartilage was further divided into deep and superficial layers according to the thickness 1/2, and the ROI was delineated to obtain the T₂* value of the corresponding area. One-way repeated measures analysis was performed to test the difference of T₂* values pre- and post-marathon. LSD tests were used to estimate the different influences of physiological activities on each articular cartilage area. Results: All cartilage areas of the knee joint did not show cartilage injury during the examination. The differences in the global T₂* values of the superficial layers of the knee cartilage before and after the half-marathon marathon were statistically significant (t=5.145, P<0.05), but the global T₂* value of the deep region were not (t=1.864, P>0.05). After a week, the T₂* values of all cartilage areas were not statistically different from those before running (t=1.062, 0.309; P>0.05). Conclusion After a single half marathon, the changes of knee cartilage composition in male amateur marathon runners are reversible. In the absence of positive findings in conventional MRI, T₂* mapping can indirectly reflect changes in biochemical composition of the articular cartilage during exercise.

Objective: To test the differences in diffusion properties-namely fractional anisotropy (FA) and apparent diffusion coefficient(ADC)-between amateur marathon runners and healthy volunteers′ thigh muscles using diffusion tensor imaging (DTI) at rest. Methods: Thirty amateur marathon runners(Group A) and 20 healthy volunteers (Group B) were recruited. All were males and their age was between 28 to 53 years. All subjects underwent both thigh DTI examination. DTI parameters FA and ADC were evaluated in thigh muscles(rectus femoris, vastus lateralis, vastus intermedius, vastus medialis, adductor longus, adductor magnus, biceps femoris long head, semitendinosus and semimembranosus)in all subjects. We tested the differences in diffusion properties between GroupA and B using independent sample t test. Results: The average FA value of the thigh muscles measured in Group A was (0.24±0.03), which was significantly lower than that in Group B=(0.27±0.03)(t=5.164,P<0.01). The average ADC value of the thigh muscles measured in Group A was (1.74±0.10)×10^-3mm²/s, which was significantly higher than that in Group B=(1.70±0.09)×10^-3mm²/s (t=2.060,P<0.05). The FA value of Group A was lower than that of Group B in the rectus femoris, vastus lateralis, vastus medialis, biceps femoris long head, semitendinosus and semimembranosus (P<0.05). The ADC value of Group A was higher than that of Group B in the vastus intermedius, vastus medialis and biceps femoris long head (P<0.05). Conclusions In the absence of positive findings from conventional MRI, DTI technique can non-invasively assess the subtle changes in the bilateral thigh muscles of amateur marathon runners at rest in the early stage of microscopic molecular level, providing important imaging evidence for early changes in skeletal muscle caused by marathon.

Objective To learn the true experiences of clinical nursing leaders like the head of nursing department and head nurses of a hospital in their implementation and management of narrative care for reference in effective implementation. Methods This study used purposive sampling and snowball sampling of phenomenological research methods. 13 nursing managers were selected from 3 tertiary hospitals in Jiangsu and Hebei province for a semi-structure interview. The interview focused on implementation of such care. Results Following four themes emerged from original interview materials. Namely, the team building experience of narrative care (led by the hospital leader, the establishment of the nursing psychology committee, and the formation of the department narrative nursing team), nurse training of narrative care (phased training, test of learning effects, and qualifications of psychological counselors ), practical management of narrative care (encouragement first, and pressure as auxiliary means), and evaluation of nursing managers on the narrative care (active role, difficulties in implementation). Conclusions As an effective way of psychological nursing care, narrative nursing deserves nationwide application. Success of the application depends on emphasis and support of nursing managers who are expected to pay high attention and promote narrative nursing with teamwork power, so as to develop the narrative care ability of nurses.