BACKGROUND:Currently,numerous experiments delve into the intricate anatomy and biomechanical behavior of distinct segments of the supraspinatus muscle.However,the impact of shoulder joint stress resulting from damage to various regions of this muscle remains a scarcely explored domain.Understanding the repercussions of supraspinatus muscle injuries across different regions on the stress distribution and magnitude of articular cartilage and the glenoid is crucial for providing some theoretical support for clinical diagnosis and treatment. OBJECTIVE:To ascertain the maximum stress values by simulating different degrees of supraspinatus muscle rupture on the humeral cartilage surface,glenoid lip,and glenoid cartilage joint surface using three-dimensional finite element software. METHODS:Normal and healthy shoulder joint CT or MRI scans were processed through Mimics and Geomagic to extract molds.Subsequently,models were constructed via Solidworks.Varying degrees of supraspinatus muscle damage were simulated for each model to mimic fractures in different regions.Finally,Ansys,mechanical software,was employed for three-dimensional finite element biomechanical analysis,calculating stress values for the humeral cartilage surface,glenoid lip,and glenoid cartilage joint surface. RESULTS AND CONCLUSION:(1)With worsening degrees of supraspinatus muscle injury,the stress on the shoulder joint cartilage surface and glenoid lip escalated.(2)Among various regions,the anterior part of the supraspinatus muscle exhibited paramount significance.(3)While supraspinatus muscle fractures of differing degrees impacted the magnitude of cartilage stress on the glenoid labial surface,the stress distribution remained constant.(4)It is indicated that during the initial stages of horizontal abduction of the shoulder joint,the anterior region assumes a pivotal role,followed by the posterior deep region.Injury to the anterior part of the supraspinatus muscle leads to a significant surge in stress within the shoulder joint's soft tissue,potentially causing damage to the top of the glenoid lip and the anterior part of the glenoid cartilage.

Objective To investigate the influencing factors of nosocomial pneumonia in elderly pa-tients with CHD and HF.Methods A total of 196 elderly CHD patients with HF diagnosed and treated in our department from March 2021 to August 2023 were enrolled,and divided into infec-ted group(n=52)and non-infected group(n=144)based on whether pulmonary infection oc-curred during hospitalization.Logistic regression analysis was used to identify the risk factors af-fecting secondary nosocomial pulmonary infection.Based on these risk factors,a comprehensive in-dex was built.ROC curve was drawn to analyze the diagnostic value of the index for secondary nosocomial pulmonary infection.Results The infected group had significantly advanced age,lar-ger proportions of NYHA grade Ⅲ to Ⅳ,smoking history,diabetes history,mechanical ventila-tion time＞48 h,length of hospital stay＞14 d,and albumin at admission＜30 g/L,and higher RDW at admission when compared with the non-infected group(P＜0.05,P＜0.01).Logistic regression analysis showed that NYHA grade Ⅲ to Ⅳ,diabetes history,mechanical ventilation time＞48 h,length of hospitalization＞14 d,albumin＜30 g/L at admission and RDW at admis-sion were risk factors for secondary nosocomial pulmonary infection in elderly CHD patients with HF(OR=2.398,95％CI:1.157-4.969;OR=2.732,95％CI:1.278-5.839;OR=2.607,95％CI:1.138-5.973;OR=3.368,95％CI:1.567-7.242;OR=2.677,95％CI:1.218-5.886;OR=1.762,95％CI:1.488-61.222).ROC curve analysis indicated that the AUC value of NYHA grade Ⅲ to Ⅳ,diabetes history,mechanical ventilation time＞48 h,length of hospitalization＞14 d,albumin＜30 g/L at admission and RDW at admission in predicting secondary nosocomial pulmonary infec-tion in elderly CHD patients with HF was 0.598,0.620,0.586,0.595,0.615 and 0.850,respectively,and the value of the comprehensive index was 0.743,which is superior to that of above single indi-cator(P＜0.05).Conclusion Age,NYHA grade,smoking history,diabetes history,mechanical ventilation time,hospital stay and albumin and RDW levels at admission have adverse effects on secondary nosocomial pulmonary infection in elderly CHD patients with HF.Our built compre-hensive index based on these risk factors has high efficacy in predicting nosocomial pulmonary in-fection.

Objective To investigate the effect and mechanism of ammonium pyrrolidine dithiocarbamate(PDTC)on neuroinflammatory injury in the penumbra of traumatic brain injury(TBI)in rats.Methods Sixty Sprague Dawley rats were divided into the PDTC group,TBI group,sham operation group and control group according to the random number table method,with 15 rats in each group.Rats in the PDTC group were intraperitoneally injected with PDTC(100 mg·kg-1)at 15 minutes before surgery;while the rats in the TBI group,sham operation group,and control group were intraperitoneally injected with the same volume of double distilled water.After the cranial window of rats in the TBI group and PDTC group was created,a 2.5 g steel rod with an inner diameter of 6.0 mm was dropped freely from a height of 75 cm through a transparent polyvinyl chloride tube with an inner diameter of 7.0 mm to impact the dura mater and induce right parietal lobe contusion and laceration to establish the TBI model;rats in the sham operation group were sealed with bone wax after the cranial window creation,without any impact applied;rats in the control group were raised under normal conditions.The modified neurological severity score(mNSS)was used to evaluate the degree of neurobehavioral damage in rats in each group at 1,4 and 7 days after modeling.At 2 days after modeling,5 rats in each group were decapitated,and brain tissues were taken for hematoxylin & eosin(HE)staining,and morphological changes of the brain tissues were observed under an optical microscope.The expressions of β-amyloid precursor protein(β-APP)and glial fibrillary acidic protein(GFAP)in the brain tissues of rats in each group were detected by immunohistochemical staining.At 24 hours after modeling,5 rats in each group were decapitated,and the right injured penumbra tissues were obtained;the expressions of nuclear transcription factor-κB(NF-κB)P65,phosphorylated NF-κB P65,inhibitor of NF-κB(IκB),phosphorylated IKB,NOD-like receptor protein 3(NLRP3)and caspase-1 protein in the right injured penumbra tissue of rats in each group were detected by Western blot,and the expressions of NF-κB P65,IκB,NLRP3 and caspase-1 mRNA in the right injured penumbra tissue of rats in each group were determined by real-time quantitative polymerase chain reaction.Results At 1,4,and 7 days after modeling,the mNSS scores of rats in the TBI group were signifi-cantly higher than those in the PDTC group,control group and sham operation group.The mNSS scores of rats in the PDTC group were significantly higher than those in the control group and sham operation group(P＜0.05);there was no statistically significant difference in mNSS scores between the sham operation group and the control group(P＞0.05).The neurons and neurogliocyte of rats in the control group and the sham operation group exhibited normal morphology,without swelling and wide-ning of intercellular space.Diffuse hemorrhagic changes were observed in the brain tissues of rats in the TBI group,with different morphologies of neuronal cell body,unclear cell membrane and cytoplasm,pyknosis of cell nuclei,often triangular shape,disappearance of normal structure and nucleoli,and diffuse white blood cells and red blood cells filling the field of vision.The lesion surrounding area of rats in the PDTC group showed ischemic changes,with mild shrinkage of neuronal volume,a uniform light red color,karyopyknosis,nuclear-cytoplasmic dissociation,disappearance of normal structure and nucleoli,and localization of neuroinflammation.There was no significant expression of β-APP and GFAP in the cerebral cortex of rats in the control group and the sham operation group,while the accumulation of β-APP and GFAP in neuronal serosae and/or axons was observed in the brain tissues of rats in the TBI group and the PDTC group.Compared with the TBI group,a decrease in the number and the expression intensity of β-APP and GFAP-positive stained neuronal cells in the cerebral cortex of rats was observed in the PDTC group.The relative expression of NF-κB P65 protein in the brain tissues of rats in the sham operation group,TBI group and PDTC group was significantly higher than that in the control group,and the relative expression of NF-κB P65 protein in the brain tissues of rats in the PDTC group was significantly higher than that in the TBI group(P＜0.05).The relative expression of phosphorylated NF-κB P65 protein in the brain tissues of rats in the PDTC group and the sham operation group was significantly lower than that in the control group,the relative expression of phosphorylated NF-κB P65 protein in the brain tissues of rats in the TBI group was significantly higher than that in the control group and the sham operation group,and the relative expression of phosphorylated NF-κB P65 protein in the brain tissues of rats in the PDTC group was significantly lower than that in both TBI group and sham operation group(P＜0.05).There was no significant difference in the relative expression of IκB protein in the brain tissues of rats between the sham operation group and the control group(P＞0.05);the relative expression of IκB protein in the brain tissues of rats in the TBI group was significantly higher than that in the control group,and the relative expression of IκB protein in the brain tissues of rats in the PDTC group was significantly lower than that in the control group,sham operation group,and TBI group(P＜0.05).The relative expression of phosphorylated IκB protein in the brain tissues of rats in the TBI group was significantly lower than that in the control group and the sham operation group,and the relative expression of phosphorylated IκB protein in the brain tissues of rats in the PDTC group was significantly higher than that in the TBI group(P＜0.05).The relative expression of NLRP3 protein in the brain tissues of rats in the sham opera-tion group was significantly higher than that in the control group,the relative expression of NLRP3 protein in the brain tissues of rats in the TBI group and the PDTC group was significantly lower than that in the sham operation group and the control group,and the relative expression of NLRP3 protein in the brain tissues of rats in the TBI group was significantly lower than that in the PDTC group(P＜0.05).The relative expression of caspase-1 protein in the brain tissues of rats in the sham opera-tion group,PDTC group,and TBI group was significantly higher than that in the control group,and the relative expression of caspase-1 protein in the brain tissues of rats in the PDTC group was significantly lower than that in the TBI group(P＜0.05).The relative expression of NF-κB P65 mRNA in the brain tissues of rats in the PDTC group,TBI group,and sham operation group was significantly higher than that in the control group,the relative expression of NF-κB P65 mRNA in the brain tissues of rats in the PDTC group and TBI group was significantly higher than that in the sham operation group,and the relative expres-sion of NF-κB P65 mRNA in the brain tissues of rats in the PDTC group was significantly lower than that in the TBI group(P＜0.05).The relative expression of IκB mRNA in the brain tissues of rats in the PDTC group and TBI group were signifi-cantly higher than that in the control group,and the expression of IκB mRNA in the brain tissues of rats in the sham operation group was significantly lower than that in the control group(P＜0.05).The relative expression of IκB mRNA in the brain tis-sues of rats in the PDTC group and TBI group was significantly higher than that in the sham operation group,and the relative expression of IκB mRNA in the brain tissues of rats in the PDTC group was significantly lower than that in the TBI group(P＜0.05).The relative expression of NLRP3 mRNA in the brain tissues of rats in the PDTC group and TBI group was significantly higher than that in the control group,the relative expression of NLRP3 mRNA in the brain tissues of rats in the sham operation group was significantly lower than that in the control group,the relative expression of NLRP3 mRNA in the brain tissues of rats in the PDTC group and TBI group was significantly higher than that in the sham operation group,and the relative expression of NLRP3 mRNA in the brain tissues of rats in the PDTC group was significantly lower than that in the TBI group(P＜0.05).The relative expression of caspase-1 mRNA in the brain tissues of rats in the sham operation group,TBI group,and PDTC group was significantly lower than that in the control group,the relative expression of caspase-1 mRNA in the brain tissues of rats in the TBI group and PDTC group was significantly higher than that in the sham operation group(P＜0.05).Conclusion PDTC can effectively improve neural functional deficit score and reduce neuroinflammatory injury in TBI rats,the mechanism of which may be related to regulating mRNA and protein expression of NF-κB/NLRP3 axis-related inflammatory injury indicators and regulating downstream inflammatory factors.

BACKGROUND:Anterior cruciate ligament injury tends to lead to secondary meniscus injury and osteoarthritis.At present,there are few studies on the mechanics of meniscus and articular cartilage injury caused by anterior cruciate ligament injury. OBJECTIVE:To study the effect of partial rupture of the anterior cruciate ligament on the stress of medial and lateral meniscus and articular cartilage of knee joint by finite element analysis. METHODS:The CT and MRI images of the knee joint of a healthy volunteer were selected,and the scan data were imported into Mimics,Geomagic and SolidWorks software.After registration and fusion,four kinds of three-dimensional knee joint models were established:models of intact anterior cruciate ligament,rupture of the posterior external tract of anterior cruciate ligament,rupture of the anterior internal tract of anterior cruciate ligament,and absence of anterior cruciate ligament.Finally,data were imported into Ansys software to apply four different modes of loads to the knee joint:Longitudinal loads of 750 N were applied to the top of the femur;longitudinal load of 750 N to the top of the femur and forward thrust of 134 N behind tibia;a longitudinal load of 750 N and a varus moment of 10 Nm were applied to the top of the femur to simulate genu varus;750 N longitudinal load and 4 Nm internal rotation moment were applied to the proximal end of the femur to simulate knee internal rotation.The finite element analysis of biomechanical stress changes of the meniscus and articular cartilage of the knee joint was carried out. RESULTS AND CONCLUSION:(1)In the straight position of the knee joint,when the anterior medial tract of the anterior cruciate ligament was broken and the anterior cruciate ligament was missing under longitudinal loads of 750 N at the top of the femur,the total stress and peak value of meniscus increased significantly,but the stress distribution of the meniscus and the stress of articular cartilage did not change significantly.In longitudinal load of 750 N to the top of the femur and forward thrust of 134 N behind tibia,the fracture of the anterior internal tract of the anterior cruciate ligament increased the tibia forward,the compressive stress of posterior angle of the meniscus increased,and the stress of the articular cartilage did not change significantly.During simulating genu varus,the posterior angular stress of the lateral meniscus decreased,the stress of the medial meniscus increased,and the stress of articular cartilage slightly decreased when anterior cruciate ligament injuries were complete.When the anterior internal tract of the anterior cruciate ligament was broken or absent under knee internal rotation,the equivalent stress peak value of femoral cartilage and tibia cartilage shifted from medial cartilage to lateral cartilage,and the stress peak value of meniscus increased significantly.At this time,the anterior internal tract of the anterior cruciate ligament played a leading role in the rotational stability of the knee joint.(2)These results indicate that the risk of secondary meniscus injury in patients with anterior and medial anterior cruciate ligament band rupture was much higher than that in patients with posterior and external anterior cruciate ligament band rupture when the knee was in the upright standing position,varus and pronation,and there was no significant difference in the impact on articular cartilage.

BACKGROUND:The incidence of medial collateral ligament injuries in the knee joint is easy to lead to secondary meniscus and cartilage damage,and long-term chronic damage can lead to the occurrence of osteoarthritis.At present,there are few studies on the mechanics of meniscus and articular cartilage injury caused by medial collateral ligament rupture. OBJECTIVE:To investigate the effect of different degrees of medial collateral ligament injury on the biomechanics of meniscus and cartilage of knee joint. METHODS:The CT and MRI examinations of the knee joint of a healthy volunteer were performed to obtain the image data.The scanning data were imported into Mimics,Geomagic,and Solidworks software in turn.After registration and fusion,a 3D model of normal knee joint was established.On this basis,models of medial collateral ligament injury in different degrees of knee joint were simulated,which were divided into four groups,including:(1)medial collateral ligament was intact;(2)deep medial collateral ligament fracture;(3)superficial medial collateral ligament fracture;(4)complete rupture of medial collateral ligament.Finally,Ansys software was introduced to apply three modes of loads to the knee joint:(1)10 N·m valvaration torque was applied to the top of the femur.(2)A 4 N·m internal torque was applied to the top of the femur.(3)A 4 N·m external torque was applied to the top of the femur.The effects of four groups of models on knee biomechanics under different loads were analyzed. RESULTS AND CONCLUSION:(1)In the extension position of the knee joint,when a 10 N·m valgus torque was applied to the knee joint,the overall stress of the posterolateral meniscus increased with different degrees of medial collateral ligament injuries,while the stress of the articular cartilage did not change significantly.The peak stress of the posterolateral meniscus increased significantly with superficial medial collateral ligament rupture.(2)In the knee extension position,when a 4 N·m internal rotation torque was applied to the knee joint,the overall stress of the medial and lateral meniscus increased after different degrees of medial collateral ligament injury.When superficial medial collateral ligament rupture occurred,the peak stress of the meniscus shifted from the anterior horn of the medial meniscus to the anterior horn of the lateral meniscus.(3)In the knee extension position,applying a 4 N·m external rotation torque to the knee joint,the peak stress of the posterolateral meniscus increased more significantly than that of the medial meniscus,and the stress of the articular cartilage changed less.(4)These results show that the risk of meniscus injury secondary to superficial medial collateral ligament rupture is much higher than that of deep medial collateral ligament rupture when the knee is in extension,and the lateral meniscus is more vulnerable to injury than the medial meniscus.Both superficial medial collateral ligament and deep medial collateral ligament play an important role in the rotational stability of the knee joint.

Objective:To explore the coverage of influenza and pneumonia vaccination and factors influencing the vaccination in children.Methods:A cross-sectional questionnaire survey was conducted in children's parents in Beijing and Gansu by using two-stage cluster-sampling to investigate the influenza and pneumonia vaccination rates and influencing factors in children.Results:A total of 2 377 parents were included in the study, and the results indicated that the influenza vaccination coverage was 35.93% and the pneumonia vaccination coverage was 16.58% in children in survey areas, the vaccination rate of both vaccines was 11.65%. The top three reasons for vaccination for both vaccines were being aware of severity of the diseases (influenza vaccine: 36.02%; pneumonia vaccine: 49.61%), being required by school or organization (influenza vaccine: 28.76%; pneumonia vaccine: 25.45%) and being aware of the susceptibility of the diseases (influenza vaccine: 26.41%; pneumonia vaccine: 13.88%). The top three reasons for having no vaccinations were personal unwillingness, concern about vaccine and vaccine accessibility. Families with multi children, living in rural areas and lower family income were the negative factors for both types of vaccinations.Conclusions:The influenza and pneumonia vaccination coverage in children need further improvement, and rural families and families with multi children are the key concern groups for expanding vaccination coverage. Health education about influenza and pneumonia vaccinations, coordinating vaccine supply and decreasing vaccine prices play an important role in improving influenza and pneumonia vaccination coverage.

Objective:To investigate the effect of sequential suture and adhesion on craniomaxillofacial skin contusion and laceration.Methods:A total of 189 patients with craniomaxillofacial skin contusion and laceration (CMFSCL) were randomly divided into three groups: 66 cases in SSA group, 63 cases in CS group and 60 cases in TS group. Operation time, visual analogue scale (VAS), Vancouver scar scale (VSS) and adverse reactions incidence were compared and analyzed between the three groups. Effect and satisfactory scale were evaluated.Results:Operation time in SSA group (10.67±1.26) min was significantly less than that in CS (18.91±1.38) min and TS group (17.96±1.43) min ( P<0.05). VAS in SSA group 24 h post-operation (3.11±1.01) was significantly lower than that in CS and TS group ( P<0.05). VSS in SSA group 6 months post-operation (1.18±0.21) was significantly lower than that in CS (3.78±1.01) ( P<0.05) and TS group (5.98±1.06) ( P<0.01). Total effective rate of SSA group (96.5%) was significantly higher than that in CS (85.7%) ( P<0.05) and TS group (56.1%) ( P<0.01); total effective rate in CS group was significantly higher than that in TS group ( P<0.05). Infection and dehiscence rates in SSA group were lower than those in CS and TS group ( P<0.01). Satisfactory rate of SSA group (99%) was significantly higher than that of CS (89.1%) and TS group (71.3%) ( P<0.05); the satisfactory rate of CS group was significantly higher than that of TS group ( P<0.05). Conclusions:Sequential suture and adhesion technique is simple and effective for craniomaxillofacial skin contusion and laceration, which is worthy of clinical promotion.

Human challenge trial (HCT) is a test in which human volunteers are intentionally infected with pathogens in order to evaluate the efficacy of candidate preventive or therapeutic drugs. During the COVID-19 pandemic, the HCT of vaccines has aroused people's attention due to its significant advantages over clinical trial. This paper introduces the concept, development and application of HCT, the advantages and limitations of HCT for vaccine evaluation, and the consideration of future HCT of COVID-19 vaccine in China.

Objective:To investigate the incidence and determinants of vaccine hesitancy towards national immunization program in China and understand the current status of parents' hesitancy to different vaccines used in national immunization program.Methods:A cross-sectional survey was conducted in Beijing, Sichuan and Gansu. The methods of proportional probability sampling and convenience sampling were used to select the eligible study subjects for questionnaire surveys.Results:A total of 3 592 parents were enrolled in the study, in whom 38.22% fully accepted all the vaccines, 59.35% agreed to let their children to receive all the vaccines but showed slight concern, and 2.42% had hesitancy to the vaccines. The vaccine with the most hesitancy was polio vaccine (0.89%), followed by diphtheria pertussis tetanus vaccine (0.70%) and hepatitis A vaccine (0.64%). The dominant reason for vaccine hesitancy was the risk-benefit perception of vaccination (31.03%), followed by the low awareness of the parents (21.84%) and the inconvenience caused by distance and time (21.84%).Conclusions:The incidence of vaccine hesitancy towards national immunization program was low in parents in China, but over 50% of the parents showed concern to the vaccines. It is essential to improve the service quality of national immunization program and strengthen the health education about the vaccination to reduce the incidence of vaccine hesitancy in parents.

Objective:To explore the clinical value of adenosine stress myocardial contrast echocardiography in detecting myocardial blood perfusion abnormalities in patients with type 2 diabetes mellitus.Methods:Twenty-six patients with type 2 diabetes mellitus clinically diagnosed from May 2019 to January 2020 in the endocrinology department of Fuwai Central China Cardiovascular Hospital and 28 healthy examinees with gender and age matched during the same period were enrolled. Routine echocardiography, rest and adenosine stress myocardial contrast echocardiography were performed, the plateau signal intensity(A value), curve rising slope(K value) and A×K value of the myocardial perfusion time-intensity curve were obtained by offline analysis. And general data such as age, gender, disease course, body mass index and glycated hemoglobin were collected, and results of the two groups were compared statistically.Results:In the rest state, the A value of the myocardial perfusion parameter in the diabetic group was not significantly different from that of the control group, both in whole and in segments ( P>0.05), while the K value and A×K value of the myocardial perfusion parameters in the diabetic group were significantly lower than those in the control group ( P<0.05). In the stress state, the A value, K value and A×K value of myocardial perfusion parameters in the diabetic group were significantly lower than those in the control group, both in whole and in segments ( P<0.05). The detection rate of myocardial perfusion abnormality in the stress state was significantly higher than that in the rest state, and the difference was statistically significant ( P<0.05). The myocardial blood flow reserve in the diabetic group was negatively correlated with the course of disease and the level of glycated hemoglobin ( r=-0.580, P=0.020; r=-0.481, P=0.013). Conclusions:Adenosine stress myocardial contrast echocardiography can be used for detection of left ventricular myocardial perfusion abnormalities in patients with type 2 diabetes mellitus, which has great clinical application value.