BACKGROUND:Intervertebral disc degeneration is a condition caused by the combined effects of various factors,such as cellular apoptosis,oxidative stress,and inflammatory responses.Currently,it is believed that the core of this condition lies in the degeneration and apoptosis of nucleus pulposus cells(NPCs).However,the specific pathological mechanisms remain unclear. OBJECTIVE:By investigating the expression of the phosphatidylinositol-3 kinase(PI3K)/protein kinase B(Akt)/hypoxia-inducible factor 1-alpha(HIF-1α)signaling pathway and the apoptosis of NPCs under different oxygen concentrations,to clarify the biological characteristics of NPCs under varying oxygen levels,and to explore the mechanisms of intervertebral disc degeneration. METHODS:Normal and degenerated NPCs were collected.The second-generation cells were used for imaging identification.The third-generation cells were cultured in the following conditions:37℃,air,100%humidity.Leibovitz's medium containing 100 μmol/L CoCl2 and 10%fetal bovine serum medium containing 100 μmol/L H2O2 were used to create distinct oxygen concentration environments for the third-generation cells,allowing for the investigation of cellular responses and behaviors under normal,low oxygen,and oxidative stress conditions.The third-generation cells were divided into six groups:normal NPCs+hypoxia,normal NPCs+normoxia,normal NPCs+oxidative stress,degenerated NPCs+hypoxia,degenerated NPCs+normoxia,and degenerated NPCs+oxidative stress groups.Cell viability and proliferation were assessed using the cell counting kit-8 method.Cell apoptosis was detected using flow cytometry.RT-PCR and western blot assay were utilized to examine the protein and mRNA expression levels of PI3K,AKT,and HIF-1α. RESULTS AND CONCLUSION:At different oxygen concentrations,the cell proliferation rate of both normal and degenerated NPCs decreased as the oxygen concentration increased.Conversely,the apoptosis rate increased as the oxygen concentration rose(P<0.05).With the normal NPCs+hypoxia group as the control group,the effect of degenerated NPCs on the apoptosis rate was highly significant(P<0.001).Oxygen concentration had a highly significant impact on both NPC proliferation rate and apoptosis rate(P<0.001).The interaction between cell degeneration and oxygen concentration significantly affected both NPC proliferation and apoptosis rates(P<0.05).At different oxygen concentrations,the protein and mRNA expression levels of PI3K,AKT,and HIF-1α in normal NPCs were highest under low oxygen concentration,followed by oxidative stress environment,and lowest under normoxia.In degenerated NPCs,the protein and mRNA expression levels of PI3K,AKT,and HIF-1α decreasd as the oxygen concentration increased.The protein and mRNA expression levels of PI3K and Akt in normal NPCs were significantly higher than those in degenerated NPCs(P<0.05).With the normal NPCs+hypoxia group as the control group,the effects of normal or degenerated NPCs,as well as oxygen concentration,on the protein and mRNA expression of PI3K,AKT,and HIF-1α were highly significant.The interaction between cell degeneration and oxygen concentration also had an extremely significant effect on the protein and mRNA expression of PI3K,AKT,and HIF-1α(P<0.001).To conclude,there is a close correlation between the proliferation and apoptosis of NPCs and both oxygen concentration and the cellular functional state.The PI3K/Akt/HIF-1α signaling pathway exhibits antagonistic regulatory effects under various cellular functional states and different oxygen concentration environments.The mechanism may be associated with the activation of the PI3K/Akt signaling pathway,which consequently transcribes HIF-1α,thus maintaining the balance of reactive oxygen species metabolism.This pathway plays a significant role in inhibiting oxidative stress,antagonizing NPCs apoptosis,and consequently delaying intervertebral disc degeneration.

Cathartic colon （CC） is a common and refractory digestive system disease， with the pathogenesis not fully clarified. The effective therapies other than laxatives and surgery remain to be developed for CC. Therefore， establishing the CC animal models that fit the disease characteristics of western medicine and syndrome characteristics of traditional Chinese medicine （TCM） is an important link to promote the research on this disease. The fitting degree of animal models with the latest Chinese and western medical diagnostic criteria is an indicator to assess the effectiveness of the animal models in simulating the disease characteristics of western medicine and syndrome characteristics of TCM. The literature review showed that the model animals， drugs and their dosage forms， doses， administration methods， and modeling period of CC varied in different studies， and the available CC animal models presented different fitting degrees with the disease characteristics of western medicine and syndrome characteristics of TCM. Rats were the preferred animals for the modeling of CC. Rhei Radix et Rhizoma preparations were commonly used for model inducing， which， however， may cause water electrolyte disorders， decreased immunity， and even death of animals at the late stage of modeling. The animals were modeled by gradually increasing the starting dose， while the starting dose and increasing dose varied. The maintenance dose was determined based on 50% of the animals having loose stools， and the end for a cycle was determined as the time when loose stools disappeared in 80% of animals. The modeling always lasted for 2-3 cycles， approximately 2-4 months. The CC models established with Rhei Radix et Rhizoma granules and rhein had high fitting degrees with the disease and syndrome characteristics. In addition， the CC animal models of TCM syndromes were still in the exploration stage. There were only the animal models of four TCM syndromes： liver depression and spleen deficiency， both Qi and Yin deficiency， Qi stagnation and blood stasis， and spleen and kidney deficiency. Efforts should be made to establish the animal models that meet the characteristics of disease of western medicine and syndromes of TCM， so as to facilitate the research on CC mechanism and drug development.

ObjectiveTo investigate rehabilitation competence among trainers and trainees whom participated in the training program entitled National Training Program of Shortage Rehabilitation Physicians (NTPSRP) using World Health Organization rehabilitation competency framework (RCF). MethodsBased on RCF, a questionnaire was developed and administrated through network using Questionnaire Star. All the trainers and trainees who participated in NTPSRP were investigated in September, 2023. ResultsA total of 911 subjects were collected from 27 provinces, including 426 trainers (teachers) and 485 trainees (students). The average age of the teachers was older, with more years of work experience and professional experience in rehabilitation medicine. The degree and professional title of the teachers was also higher. The overall internal consistency reliability of the questionnaire was good (Cronbach's α = 0.988), and all the internal consistency reliability in five fields was good (Cronbach's α > 0.9). The five dimensional structure of RCF in the results was consistent with the prior model established by RCF theory. The self-ratings of all physicians in the five fields were higher than the median level, and was higher in the teachers than in the students [(3.42±0.68) vs. (2.73±0.80), P < 0.001]. Gender and years of experience in rehabilitation medicine were independent factors for the total score of the questionnaire. The total self-rating of female students was 9.65 points lower than that of the male (95%CI 4.386 to 14.914); and one more year in rehabilitation medicine would increase 1.78 points in self-rating (95%CI 1.140 to 2.419). ConclusionThe structure and content of RCF can be used to evaluate the competence of rehabilitation physicians. The teachers and students of NTPSRP are eligible to RCF. RCF-based evaluation can be used to guide the development of continuing education courses for rehabilitation professionals.