Pathological progress and remission strategies of osteoarthritic lesions caused by long-term joint immobilization

OBJECTIVE

While joint immobilization is a useful repair method for intra-articular ligament injury and periarticular fracture, prolonged joint immobilization can cause multiple complications. A better understanding how joint immobilization and remobilization impact joint function and homeostasis will help clinicians develop novel strategies to reduce complications.

DESIGN

We first determined the effects of long-term immobilization on joint pain and osteophyte formation in patients after an extraarticular fracture or ligament injury. We then developed a mouse model of joint immobilization and harvested the knee joint samples at 2, 4, and 8 weeks. We further determined the effects of remobilization on recovery of the osteoarthritis (OA) lesions induced by immobilization in mice.

RESULTS

We found that the long-term (6 weeks) joint immobilization caused significant joint pain and osteophytes in patients. In mice, 2-week immobilization already induced moderate sensory innervation and increased pain sensitivity and infiltration in synovium without inducing marked osteophyte formation and cartilage loss. Long-term immobilization (4 and 8 weeks) induced more severe sensory innervation and inflammatory infiltration in synovium, massive osteophyte formation on both sides of the femoral condyle, and the edge of the tibial plateau and significant loss of the articular cartilage in mice. Remobilization, which ameliorates normal joint load and activity, restored to certain extent some of the OA lesions and joint function in mice.

CONCLUSIONS

Joint immobilization caused multiple OA-like lesions in both mice and humans. Joint immobilization induced progressive sensory innervation, synovitis, osteophyte formation, and cartilage loss in mice, which can be partially ameliorated by remobilization.

Application of PVC pipes as an adjustable bilateral traction device in lower limb fractures

OBJECTIVE

To introduce a new type of simple adjustable bilateral bidirectional polyvinyl chloride (PVC) tube traction device and discuss the value of using this device before surgery in patients with lower limb fractures.

METHODS

To introduce the manufacturing process of an adjustable bilateral traction device made of PVC pipes. From August 2018 to November 2019, the data of 36 patients with lower limb fractures who were treated with this traction device were retrospectively analysed. The treatment outcomes were analysed, including length of both lower limbs, fracture reduction, lower limb mobility, visual analogue scale (VAS) score, incidence of complications, and patient satisfaction.

RESULTS

All patients were able to move the affected limb immediately after using the device. The patient's pain was significantly reduced, they were able to turn over freely during bed rest, and the length of the affected limb was restored to that of the healthy limb. Thirty-four (94.5%) patients were satisfied with the reduction of the fracture end, 2 (5.5%) patients with tibiofibular fractures showed angular displacement of the fractured end and satisfactory reduction after the position of the bone traction needle was adjusted; 7 (19.5%) patients developed deep vein thrombosis of the affected lower limb during traction; there was no decubitus or vascular nerve injury, and the overall complication rate was 25% (9/36). All the patients and their families were satisfied with the results of this treatment.

CONCLUSION

The aim of this study is to introduce a new type of traction device. It is advantageous in that it is light weight, low cost, easy to assemble, promotes immediate movement of the affected limb after assembly, improves patient comfort and can be used with a titanium steel needle for MRI examination under traction. In the clinical setting, it has been shown to be suitable for the temporary treatment of patients with lower leg fractures prior to surgery, particularly patients who, for various reasons, require nonsurgical treatment in the short term.

[Efficacy and influencing factors of immunotherapy combined with chemotherapy and bevacizumab in patients with non-small cell lung cancer after epidermal growth factor receptor tyrosine kinase inhibitors treatment failure]

Objective: To investigate the efficacy and influencing factors of immunotherapy combined with chemotherapy and bevacizumab in patients with non-small cell lung cancer (NSCLC) who failed epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) treatment. Methods: A retrospective analysis was made on the clinical data of 60 NSCLC patients who were treated with immunotherapy combined with chemotherapy and bevacizumab after EGFR-TKIs treatment failure in the Affiliated Cancer Hospital of Shandong First Medical University from January 2019 to March 2022. Patients were followed up by telephone or outpatient review up to October 1, 2022, with a median follow-up of 8.2 months (95%CI: 7.1-9.3). All 60 patients were followed up. The response evaluation criteria in solid tumors were used to evaluate the short-term efficacy. The adverse reactions of patients were evaluated according to the common terminology criteria for adverse events. The survival curve was drawn by Kaplan-Meier method. Cox proportional hazard regression models were utilized to analyze the influencing factors of progression-free survival (PFS). Results: Among the 60 NSCLC patients, 22 were males. The age ranged from 41 to 75 years, with a median age of 61 years. Eleven patients had partial response, 19 patients had stable disease and 30 patients had progressive disease. The median PFS was 8.2 months (95%CI: 7.2-9.2). The median PFS of patients with low expression of programmed death receptor-ligand 1 (PD-L1) [Tumor cell Proportion Score (TPS)<1%], moderate expression of PD-L1 (1%≤TPS≤49%), and high expression of PD-L1 (TPS≥50%) were 6.4 (95%CI: 4.8-8.0), 8.3 (95%CI: 7.3-9.3) and 10.6 months (95%CI: 7.2-14.1), respectively, and there were statistically significant differences (χ²=13.58, P<0.001). Multivariate Cox proportional risk regression model analysis showed that age>65 years old (HR=4.017, 95%CI: 1.468-10.992, P=0.007) was a risk factor for PFS in NSCLC patients who received immunotherapy combined with chemotherapy and bevacizumab after EGFR-TKIs treatment failure. Moderate expression of PD-L1 (HR=0.360, 95%CI: 0.139-0.930, P=0.035) and high expression of PD-L1 (HR=0.155, 95%CI: 0.039-0.625, P=0.009) were protective factors for PFS. Most of the treatment-related adverse reactions in the whole group were grade 1-2, including bone marrow suppression (n=24), nausea (n=25), decreased appetite (n=24), fatigue (n=22), vomiting (n=18), abnormal liver function (n=17), blood creatinine increased (n=10), and so on. These were tolerated by the patients. Conclusions: NSCLC patients who failed EGFR-TKIs treatment can tolerate adverse reactions related to immunotherapy combined with chemotherapy and bevacizumab treatment. PFS is significantly prolonged in those aged≤65 years and those with moderate and high expression of PD-L1.

The number of metabolic syndrome risk factors predicts alterations in gut microbiota in Chinese children from the Huantai study

BACKGROUND

Evidence on the effect of gut microbiota on the number of metabolic syndrome (MetS) risk factors among children is scarce. We aimed to examine the alterations of gut microbiota with different numbers of MetS risk factors among children.

METHODS

Data were collected from a nested case-control study at the baseline of the Huantai Childhood Cardiovascular Health Cohort Study in Zibo, China. We compared the differences in gut microbiota based on 16S rRNA gene sequencing among 72 children with different numbers of MetS risk factors matched by age and sex (i.e., none, one, and two-or-more MetS risk factors; 24 children for each group).

RESULTS

The community richness (i.e., the total number of species in the community) and diversity (i.e., the richness and evenness of species in the community) of gut microbiota decreased with an increased number of MetS risk factors in children (P for trend < 0.05). Among genera with a relative abundance greater than 0.01%, the relative abundance of Lachnoclostridium (P_FDR = 0.009) increased in the MetS risk groups, whereas Alistipes (P_FDR < 0.001) and Lachnospiraceae_NK4A136_group (P_FDR = 0.043) decreased in the MetS risk groups compared to the non-risk group. The genus Christensenellaceae_R-7_group excelled at distinguishing one and two-or-more risk groups from the non-risk group (area under the ROC curve [AUC]: 0.84 - 0.92), while the genera Family_XIII_AD3011_group (AUC: 0.73 - 0.91) and Lachnoclostridium (AUC: 0.77 - 0.80) performed moderate abilities in identifying none, one, and two-or-more MetS risk factors in children.

CONCLUSIONS

Based on the nested case-control study and the 16S rRNA gene sequencing technology, we found that dysbiosis of gut microbiota, particularly for the genera Christensenellaceae_R-7_group, Family_XIII_AD3011_group, and Lachnoclostridium may contribute to the early detection and the accumulation of MetS risk factors in childhood.

Electrothermally Driven Reconfiguration of Microrobotic Beam Structures for the ChipSail System

Solar sailing enables efficient propellant-free attitude adjustment and orbital maneuvers of solar sail spacecraft with high area-to-mass ratios. However, the heavy supporting mass for large solar sails inevitably leads to low area-to-mass ratios. Inspired by chip-scale satellites, a chip-scale solar sail system named ChipSail, consisting of microrobotic solar sails and a chip-scale satellite, was proposed in this work. The structural design and reconfigurable mechanisms of an electrothermally driven microrobotic solar sail made of Al\Ni₅₀Ti₅₀ bilayer beams were introduced, and the theoretical model of its electro-thermo-mechanical behaviors was established. The analytical solutions to the out-of-plane deformation of the solar sail structure appeared to be in good agreement with the finite element analysis (FEA) results. A representative prototype of such solar sail structures was fabricated on silicon wafers using surface and bulk microfabrication, followed by an in-situ experiment of its reconfigurable property under controlled electrothermal actuation. The experimental results demonstrated significant electro-thermo-mechanical deformation of such microrobotic bilayer solar sails, showing great potential in the development of the ChipSail system. Analytical solutions to the electro-thermo-mechanical model, as well as the fabrication process and characterization techniques, provided a rapid performance evaluation and optimization of such microrobotic bilayer solar sails for the ChipSail.