Effect of ST36 electroacupuncture on the switch of skeletal muscle fibres in mice with sciatic nerve dissociation.

Skeletal muscle is striated muscle that moves autonomously and is innervated by peripheral nerves. Peripheral nerve injury is very common in clinical treatment. However, the commonly used treatment methods often focus on the regeneration of the injured nerve but overlook the pathological changes in the injured skeletal muscle. Acupuncture, as the main treatment for denervated skeletal muscle atrophy, is used extensively in clinical practice. In the present study, a mouse model of lower limb sciatic nerve detachment was constructed and treated with electroacupuncture Stomach 36 to observe the atrophy of lower limb skeletal muscle and changes in skeletal muscle fibre types before and after electroacupuncture Stomach 36 treatment. Mice with skeletal muscle denervation showed a decrease in the proportion of IIa muscle fibres and an increase in the proportion of IIb muscle fibres, after electroacupuncture Stomach 36. The changes were reversed by specific activators of p38 MAPK, which increased IIa myofibre ratio. The results suggest that electroacupuncture Stomach 36 can reverse the change of muscle fibre type from IIb to IIa after denervation of skeletal muscle by inhibiting p38 MAPK. The results provide an important theoretical basis for the treatment of clinical peripheral nerve injury diseases with electroacupuncture, in addition to novel insights that could facilitate the study of pathological changes of denervated skeletal muscle.

The longitudinal relationship between bullying victimization and depressive symptoms for middle school students: A cross-lagged panel network analysis.

BACKGROUND: Previous research about the relationship between bullying victimization and adolescent depressive symptoms was mostly based on latent variable modeling. This study, instead, applied item-level analysis to explore the cross-sectional relationship and longitudinal development between bullying victimization and adolescent depressive symptoms with network models. METHODS: This study used Olweus Bully/Victim Questionnaire and Children's Depression Inventory to collect data. A total of 1911 middle school students (55.2 % female; Mage = 12.98 ± 0.60 at T1) completed measures on four occasions at 6-month intervals. Nine network analysis models were employed to better understand the relationship between variables. RESULTS: (1) "Being threatened or intimidated" was the most influential bullying behavior within bullying victimization items; (2) "being excluded", "being spoken ill of" and "negative mood" were the bridge items between bullying victimization and adolescent depressive symptoms; (3) the most influential bullying victimization item on adolescent depressive symptoms was "being robbed or blackmailed" for short-term development and "being excluded" for long-term development. While the most affected depressive symptom by bullying victimization was "anhedonia" for short-term development and "negative mood" for long-term development. LIMITATIONS: Self-report measure is adopted for all variables in the study, and there may be some deviation. Due to the questionnaires, the items of bullying behaviors and depressive symptoms included in the network analysis are limited. CONCLUSIONS: From the item level, this study found more specific relationships between bullying victimization and adolescent depressive symptoms. These findings highlight depressed mood and anhedonia are depressive symptoms that should be more paid attention to in clinical intervention for bullying victims.