BACKGROUND: Polylactic acid copolymer bone scaffold has excellent biodegradability, and it is easy to be shaped and can promote the formation and growth of bone tissue and blood vessel.OBJECTIVE: To observe the effects of adipose-derived stem cells(ADSCs)/poly(lactic-co-glycolic acid) (PLGA) complex on the biomechanical properties after fracture healing in osteoporotic bone.METHODS: Sixty Sprague-Dawley rats were randomly divided into four groups: blank control group received no treatment; the bilateral tibial fracture model was made after 3 months of bilateral ovarian resection in model group; the bilateral tibial fracture model was made and ADSCs were implanted into the bone after 3 months of bilateral ovarian resection in cell therapy group; the bilateral tibial fracture model was made and the PLGA/ADSCs complex was implanted after 3 months of bilateral ovarian resection in combined treatment group.The bone mineral density, callus thickness, biomechanical parameters and the microstructure of the trabecular bone were detected.RESULTS AND CONCLUSION: (1) The bone density: The bone density of the model group was significantly lower than that of the blank control group (P < 0.05); the bone mineral density of the cell therapy group and the combined treatment group was higher than that of the model group (P < 0.05), but lower than that of the control group (P < 0.05); and the bone mineral density of the combination treatment group was higher than that of the cell therapy group (P < 0.05). (2)Thickness of the callus: The thickness of the callus in the cell therapy group and combined treatment group was higher than that of the model group and blank control group (P < 0.05); moreover, the thickness of the callus in the combined treatment group was higher than that of the cell therapy group (P < 0.05). (3) Biomechanical test: The failure load, stress and shear strength, elastic modulus were decreased in the model group compared with the blank control group (P < 0.05), while the shear strain increased (P < 0.05). Compared with the model group, the failure load, ultimate stress, shear strength, elastic modulus were increased in the cell therapy group and combined treatment group (P < 0.05), and the shear strain was decreased (P < 0.05). Moreover, the combined treatment group showed more changes in these biomechanical parameters (P < 0.05). (4) The trabecular bone microstructure: The model group presented with trabecular derangement, spacing increases, and even fracture and lacuna. After ADSCs or ADSCs/PLGA transplantation,the trabecular bones increased in number, thickness, and spacing, and the number of lacunae reduced. In conclusion,ADSCs combined with PLGA in the treatment of osteoporotic fracture can significantly improve the biomechanical parameters of bone tissue after healing.

BACKGROUND: SSh as a Hedgehog signal protein can promote bone development, growth and remodeling.OBJECTIVE: To investigate the effect of bone marrow mesenchymal stem cells (BMSCs) combined with Shh modified nano-hydroxyapatite/collagen (nHAC) in the repair of femoral defects in rats.METHODS: Forty-eight Sprague-Dawley rats were randomly divided into four groups, and the model of femoral defects was established in these rats. At 14 days after modeling, experimental group was implanted with the BMSCs/Shh modified nHAC, scaffold group was implanted with simple nHAC, cell scaffold group was implanted with BMSCs/nHAC,and blank control group was without any implantation. At 3, 6, 9, 12 weeks after repair, X-ray examination, bone density measurement and bone biopsy in bone defect area were performed.RESULTS AND CONCLUSION: (1) X-ray examination: The Lane-Sandhu X-ray score and bone mineral density value in the experimental group at different time points after operation were significantly higher than those in the other three groups (P < 0.05). (2) Hematoxylin-eosin staining: 12 weeks after repair, a small amount of bone tissues but no bone marrow formed in the scaffold group; a small amount of bone tissues with absence of bone marrow formed in the cell scaffold group, and the residual scaffold was visible; in the experimental group, the scaffold was completely absorbed,and mature bone and medullary cavity formed with presence of bone marrow. (3) Scanning electron microscope observation: 12 weeks after repair, irregular arrangement of bone fibers and a large number of bone fossae were observed in the scaffold group; the cell scaffold group showed a large number of osteoblasts, but bone fibers still arranged irregularly; in the presence of the Haversian system, a large number of regularly arranged bone trabeculae were detective in the experimental group. These results elucidate that the Shh modified nHAC/BMSCs complex can promote the repair of bone defects.

Objective:To investigate the surgical approaches and clinical outcomes of endoscopic endonasal approaches (EEA) for trigeminal schwannomas(TSs).Methods:Clinical data, surgical videos and outpatient follow-up notes of 41 patients with TSs and underwent EEA between January 2013 to October 2022 in the Department of Neurosurgery of the First Affiliated Hospital of Nanchang University were retrospectively studied. The patients were 19 males and 22 females, with an average age of 45.3 (22-63) years old. Twenty-four patients had TSs on the left and 17 on the right. According to Jeong's classification, for 6 TSs with type MP, 2 tumours were resected by trans-Meckel's cave approach (TMCA) alone, and the remaining 4 TSs were resected by combined transclival approach (TCA). For the 4 tumours that involved infratemporal fossa(2 of type E3, 1 of type mE3 and 1 of type Mpe3), the surgery were performed via a trans-prelacrimal recess approach(TPRA), of which the operation for type Mpe3 was combined with a TMCA. The trans-laminal papyracea approach (TLPA) was applied to remove 2 tumours of type E1. The rest of 29 patients received the surgery by TMCA alone to remove tumours including 15 of types M, 10 of type Mp, 1 of type ME2, 2 of type E2 and 1 of type MpE2. Gross total tumour resection was achieved in 40 patients(97.6%), with only 1 patient (2.4%) had a subtotal tumour resection.Results:A total of 40 patients had completed the long-term follow-up, with 1 patient lost in follow-up. The average follow-up period was 34(3-101) months; No tumour recurrence or progression was observed over follow-up. After the surgery, preoperative symptoms were improved in 34 patients(89.5%). The main improved symptoms were: facial numbness(78.9%), facial pain(70.0%), headache(88.2%), mastication weakness (50.0%), poor vision (60.0%), diplopia (83.3%), and abducens nerve palsy (100%). Transient and permanent neurological deficits occurred in 8 (19.5%) and 9 (22.0%) patients, respectively. Cerebrospinal fluid leakage and internal carotid artery injury occurred in 1 patient each.Conclusion:According to the location of a tumour, an appropriate EEA should be selected and satisfactory results can be achieved for all types of tumours, except the TSs that has the main body of the tumour located in the posterior cranial fossa.

OBJECTIVE: To investigate the level of formaldehyde in the air of anatomical laboratories and to explore the effect of different prevention measures on reducing the level of formaldehyde. METHODS: The level of formaldehyde in two morphological laboratories of a medical college of a university were measured with a comprehensive atmospheric sampler at different physical ventilation time,different time after spraying biological enzymes and different masks. RESULTS: The level of formaldehyde decreased with the increase of ventilation time in front,middle and back of the laboratory( P < 0. 05).The level of formaldehyde at 30 and 60 minutes after spraying bio-enzymes in three parts of the laboratory was lower than that at 0 minute in the same part of the laboratory( P < 0. 05),and lower than that in the bio-enzymes non-spraying laboratory at the same part and same time point( P < 0. 05). At 0,30 and 60 minutes ventilation time points,the level of formaldehyde in the activated carbon mask group was lower than that in the normal sampling group,the non-woven mask group and the defatted gauze mask group at the same time point( P < 0. 05). CONCLUSION: Both physical ventilation and bio-enzyme degradation can reduce indoor formaldehyde pollution. Active carbon mask can achieve good protection effect.