BACKGROUND:Studies have shown that different durations of pressure application on normal muscles can produce varying physiological responses.OBJECTIVE:To explore the expression levels of inflammatory factors tumor necrosis factor α and nuclear κB in skeletal muscle under different pressure durations.METHODS:Twenty healthy male SPF-grade Sprague-Dawley rats were randomly divided into four groups:control group,10-second pressure group,20-second pressure group,and 30-second pressure group.The right leg of each rat was used for the experiment.The control group received no intervention,while rats in each pressure group were anesthetized by intraperitoneal injection of 2%pentobarbital sodium(35 mg/kg),and the thin femoral muscle of the rats was pressed continuously at a constant pressure of 200 kPa using a homemade mechanical pressure device for 10,20,and 30 seconds,respectively.Muscle tissue at the pressing site of the right hind limb was collected immediately after pressure.Hematoxylin-eosin staining was used to observe the morphological changes of skeletal muscle tissues and changes in the cross-sectional area of muscle fibers,and immunohistochemistry was used to detect the expression levels of tumor necrosis factor α and nuclear factor κB in rat skeletal muscle.RESULTS AND CONCLUSION:Hematoxylin-eosin staining results revealed that the pressure groups showed loosely arranged skeletal muscle fibers,reduced cross-sectional area and diameter,and enlarged intermuscular spaces.Compared with the control group,the cross-sectional area of muscle fibers was significantly reduced in the pressure groups(P<0.05),but there was no significant difference between the three pressure groups(P>0.05).The 10-second pressure group showed no significant presence of red blood cells in the interstitial spaces,while the 20-second pressure group exhibited a small amount of red blood cells,and the 30-second pressure group showed capillary dilation with red blood cells in the interstitial spaces.The expression level of tumor necrosis factor α in the 30-second pressure group was significantly higher than that in the control group(P<0.05).The expression level of nuclear factor κB in skeletal muscle showed no significant difference among groups(P>0.05).To conclude,skeletal muscle undergoes morphological changes and reduced cross-sectional area after pressure at 200 kPa,but there is no significant difference among the 10-,20-,and 30-second pressure groups.As the duration of pressure increases to 30 seconds,the inflammatory factor tumor necrosis factor α is activated,but nuclear factor κB remains unaffected,suggesting that inflammatory factors may express under short-term pressure,while transcription factors show no significant change.

BACKGROUND:Studies have shown that different durations of pressure application on normal muscles can produce varying physiological responses.OBJECTIVE:To explore the expression levels of inflammatory factors tumor necrosis factor α and nuclear κB in skeletal muscle under different pressure durations.METHODS:Twenty healthy male SPF-grade Sprague-Dawley rats were randomly divided into four groups:control group,10-second pressure group,20-second pressure group,and 30-second pressure group.The right leg of each rat was used for the experiment.The control group received no intervention,while rats in each pressure group were anesthetized by intraperitoneal injection of 2%pentobarbital sodium(35 mg/kg),and the thin femoral muscle of the rats was pressed continuously at a constant pressure of 200 kPa using a homemade mechanical pressure device for 10,20,and 30 seconds,respectively.Muscle tissue at the pressing site of the right hind limb was collected immediately after pressure.Hematoxylin-eosin staining was used to observe the morphological changes of skeletal muscle tissues and changes in the cross-sectional area of muscle fibers,and immunohistochemistry was used to detect the expression levels of tumor necrosis factor α and nuclear factor κB in rat skeletal muscle.RESULTS AND CONCLUSION:Hematoxylin-eosin staining results revealed that the pressure groups showed loosely arranged skeletal muscle fibers,reduced cross-sectional area and diameter,and enlarged intermuscular spaces.Compared with the control group,the cross-sectional area of muscle fibers was significantly reduced in the pressure groups(P<0.05),but there was no significant difference between the three pressure groups(P>0.05).The 10-second pressure group showed no significant presence of red blood cells in the interstitial spaces,while the 20-second pressure group exhibited a small amount of red blood cells,and the 30-second pressure group showed capillary dilation with red blood cells in the interstitial spaces.The expression level of tumor necrosis factor α in the 30-second pressure group was significantly higher than that in the control group(P<0.05).The expression level of nuclear factor κB in skeletal muscle showed no significant difference among groups(P>0.05).To conclude,skeletal muscle undergoes morphological changes and reduced cross-sectional area after pressure at 200 kPa,but there is no significant difference among the 10-,20-,and 30-second pressure groups.As the duration of pressure increases to 30 seconds,the inflammatory factor tumor necrosis factor α is activated,but nuclear factor κB remains unaffected,suggesting that inflammatory factors may express under short-term pressure,while transcription factors show no significant change.

Objective:To investigate risk factors for early mortality (EM) in patients with newly diagnosed multiple myeloma (NDMM) and to build an EM-predictive model.Methods:In a cohort of 275 patients with NDMM, risk factors for EM at 6, 12, and 24 months after diagnosis (EM6, EM12, and EM24, respectively) were determined to establish a model to predict EM.Results:The rates of EM6, EM12, and EM24 were 5.5% , 12.7% , and 30.2% , respectively. The most common cause for EM was disease progression/relapse, accounting for 60.0% , 77.1% , and 84.3% of EM6, EM12, and EM24, respectively. EM6 was associated with corrected serum calcium >2.75 mmol/L and platelet count <100×10 9/L, whereas risk factors for EM12 included age >75 years, ISS Ⅲ, R-ISS Ⅲ, corrected serum calcium >2.75 mmol/L, serum creatinine >177 μmol/L, platelet count <100×10 9/L, and bone marrow plasma cell ratio ≥ 60% . In addition to the risk factors for EM12, EM24 was also associated with male sex and 1q21 gain. By multivariate analysis, age >75 years, platelet count <100×10 9/L, and 1q21 gain were independent risk factors for EM24 but there were no independent risk factors significantly associated with EM6 and EM12. Using a scoring system including these three risk factors, a Cox model for EM24 was generated to distinguish patients with low (score<3) and high (score ≥ 3) risk. The sensitivity and specificity of the model were 20.7% and 99.2% , respectively. Further, an internal validation performed in a cohort of 183 patients with NDMM revealed that the probability of EM24 in high-risk patients was 26 times higher than that in low-risk patients. Moreover, this model was also able to predict overall survival. The median overall survival of patients with scores of 0, 1, 2, 3, 4, and 5 were 59, 41, 22, 17.5, and 16 months, respectively. Conclusion:In the study cohort, the EM6, EM12, and EM24 rates were 5.5% , 12.7% , and 30.2% , respectively, and disease progression or relapse were main causes of EM. An EM24-predictive model built on three independent risk factors for EM24 (age>75 years, platelet count<100×10 9/L, and 1q21 gain) might predict EM risk and overall survival.

BACKGROUND:Chronic ankle instability affects normal life severely. Therefore, chronic ankle instability causes more and more attention of experts, and choice of reasonable and effective diagnosis and targeted treatment method for chronic ankle instability in early stage has become an important issue in the clinic.
OBJECTIVE:To review literature research on the diagnosis and treatment of chronic ankle instability in recent years, and to provide reference and evaluation criteria for the diagnosis and reasonable and effective treatment of chronic ankle instability in clinical practice.
METHODS:We searched PubMed database, China National Knowledge Infrastructure, Wanfang database and VIP database for clinical and basic experimental research on chronic ankle instability. Keywords were“chronic ankle, instability, diagnosis, rehabilitation exercises, surgery methods, research progress”in Chinese and“chronic ankle, instability, diagnosis, rehabilitation exercises, surgical methods, research”in English. Total y 40 literatures were analyzed.
RESULTS AND CONCLUSION:Because of the special anatomical features and biomechanical advantages of the ankle, we should first consider the early diagnosis and effective treatment in chronic ankle instability patients. The treatment should focus on the anatomic characteristics, biomechanic characteristics, etiology of chronic ankle and diagnostic methods of the ankle joint. Conservative treatment and rehabilitation exercises after surgery play a major role in the recovery of chronic ankle instability. The use of balance board, tilting board, and climbing machines is an effective rehabilitation exercises for chronic ankle instability. The application of AOFOS-hind foot and ankle fibula reaction time is important for the assessment of functional recovery of the ankle joint. The emergence of arthroscope is an important clinical research direction of ankle surgery. This plays a significant effect on the treatment of chronic ankle instability.