Contextual Fear Learning and Extinction in the Primary Visual Cortex of Mice / 神经科学通报·英文版

Fear memory contextualization is critical for selecting adaptive behavior to survive. Contextual fear conditioning (CFC) is a classical model for elucidating related underlying neuronal circuits. The primary visual cortex (V1) is the primary cortical region for contextual visual inputs, but its role in CFC is poorly understood. Here, our experiments demonstrated that bilateral inactivation of V1 in mice impaired CFC retrieval, and both CFC learning and extinction increased the turnover rate of axonal boutons in V1. The frequency of neuronal Ca2+ activity decreased after CFC learning, while CFC extinction reversed the decrease and raised it to the naïve level. Contrary to control mice, the frequency of neuronal Ca2+ activity increased after CFC learning in microglia-depleted mice and was maintained after CFC extinction, indicating that microglial depletion alters CFC learning and the frequency response pattern of extinction-induced Ca2+ activity. These findings reveal a critical role of microglia in neocortical information processing in V1, and suggest potential approaches for cellular-based manipulation of acquired fear memory.

Severe diabetic foot repaired by tibial bone transverse transport combined with flap transfer: Report of 7 cases / 中华显微外科杂志

Objective:To investigate the clinical effect of Ilizarov technique of tibial bone transverse transport combined with flap transfer in the treatment of severe diabetic foot.Methods:From April 2016 to March 2020, 7 patients with severe diabetic foot were treated by Ilizarov technique of tibial bone transverse transport combined with flap transfer in the Department of Hand and Foot Surgery of Foshan Nanhai Public Health Hospital. Diabetes Wagner classification: 2 cases were in Grade 3, in which, 1 case was ulcer in right heel and deep plantar with abscess and infection, and 1 case was ulcer in left great toe and phalanx infection; Other 5 cases were in Grade 4, of them, 2 cases were gangrene in proximal and distal of left great toe, 1 case were gangrene and infection in proximal, middle and distal segment of right 2nd toe, 1 case were gangrene and infection in proximal, middle and distal segment of left 4th toe, and 1 case were gangrene in distal segment of left 4th toe. Wound area was 2.0 cm×2.0 cm-6.0 cm×12.0 cm. Sural neurouascular flaps were used in 1 case, dorsal plantar artery flaps in 4 cases and medial plantar artery flaps in 2 cases. Size of flap was 2.0 cm×2.0 cm-6.0 cm×12.0 cm. Follow-up was conducted regularly by outpatient clinic, telephone and WeChat interviews. Content of the follow-up included foot wound healing, skin temperature of dorsal foot, lower limb paralysis, puncture exudation of external fixation stent, and blood supply of calf skin. Foot function was assessed according to the American Orthopedic Foot and Ankle Association (AOFAS) score.Results:All 7 patients entered the follow-up for 6-28 months, with an average of 8.2 months. All the foot ulcers healed. The pain of affected limbs eased off in 5 patients, and 2 patients had significant pain relief in affected limbs. Foot paralysis significantly alleviated in 7 patients, with calf skin temperature increased (1.81±0.56) ℃, and no recurrence of foot ulcers. According to AOFAS score, 3 cases were excellent, 3 cases were good and 1 case was fair.Conclusion:Ilizarov technique of tibial bone transverse transposition combined with flap transfer in the treatment of severe diabetic foot has a good clinical effect and it could be an option in the treatment of diabetic foot.

Application of Free Venous Flap with Tendons and Nerves for Repairing Compound Palmar Tissue Defects / 现代医院

Objective To explore a one-time repairing method for defects in palmar skin soft tissue, proper palmar nerves and arteries, and flexor tendon.Methods From March 2011 to June 2016, the defects in palamar skin, nerves, blood vessels or flexor tendons of 21 fingers in 20 cases were repaired by using the resected superficial veins and tendons and nerves of skin soft tissue on axes of indicis proprius tendon (extensor digiti quinti) or forearm-palmaris longus tendon or foot back short tendons of the first or second toes were cut according to the defects in palmar skin soft tissue, nerves, blood vessels and flexor tendon, Results All the vein flaps of the 20 cases were survived.The patients were followed up for 6 to 24 months.Both the shape and function of the fingers recovered well.The flaps were of good quality, with no obvious pigmentation, and good at sensations (The sensation between two points were 9 mm on average).Conclusion It was a simpler and more convenient way to repair defects in palmar skin soft tissue, nerves, blood vessels and flexor tendons using free venous flap with tendons and nerves for transplantation.It also ensures the blood-supply without sacrificing the main vessels, and thus it is an ideal method for repairing simultaneous defects in skin soft tissue, nerves and flexor tendon.