Osteoarthritis(OA)is a common joint disease in clinical practice,and cartilage damage is a typical pathological change.The pathogenesis of OA is complex,and various adverse factors can lead to the occurrence of OA.Mitochondria are im-portant organelles within cells and play important roles in cellular physiological and pathological activ-ities.Mitochondrial quality control is an important regulatory mechanism in the body to maintain nor-mal mitochondrial structure and function,mainly including mitochondrial biogenesis,mitochondrial dynamics,mitochondrial autophagy,mitochondrial oxidative stress,and other forms.The imbalance of mitochondrial quality control in chondrocytes is closely related to the occurrence and development of osteoarthritis,and regulating the balance of mi-tochondrial quality control is a potential therapeu-tic point for osteoarthritis.The author reviewed rel-evant research literature in recent years to provide a review of the relationship between mitochondrial quality control and the occurrence and develop-ment of osteoarthritis,in order to provide new ideas and directions for the research and diagnosis and treatment strategies of osteoarthritis.

Osteoarthritis(OA)is a common joint disease in clinical practice,and cartilage damage is a typical pathological change.The pathogenesis of OA is complex,and various adverse factors can lead to the occurrence of OA.Mitochondria are im-portant organelles within cells and play important roles in cellular physiological and pathological activ-ities.Mitochondrial quality control is an important regulatory mechanism in the body to maintain nor-mal mitochondrial structure and function,mainly including mitochondrial biogenesis,mitochondrial dynamics,mitochondrial autophagy,mitochondrial oxidative stress,and other forms.The imbalance of mitochondrial quality control in chondrocytes is closely related to the occurrence and development of osteoarthritis,and regulating the balance of mi-tochondrial quality control is a potential therapeu-tic point for osteoarthritis.The author reviewed rel-evant research literature in recent years to provide a review of the relationship between mitochondrial quality control and the occurrence and develop-ment of osteoarthritis,in order to provide new ideas and directions for the research and diagnosis and treatment strategies of osteoarthritis.

The connection between tendons and bones is called the tendon bone connection. With the continuous improvement of national sports awareness, excessive exercises and the related intensity are prone to damage the tendon bone connection. Tendon bone healing is a complex repair and healing process involving multiple factors, and good tendon bone healing is a prerequisite for its physiological function. The complexity of tendon bone structure also poses great challenges to the repair of tendon bone injuries. In recent years, researches have found that stem cells, growth factors, macrophages, and other factors are closely related to the healing process of tendon bone injuries, among which macrophages play an important role in the healing process. The authors reviewed relevant research literature in recent years and summarized the role of macrophages in tendon bone healing, in order to provide new ideas and directions for treatment strategies to promote tendon bone healing.
Humans ; Macrophages/metabolism* ; Wound Healing ; Animals ; Tendons/physiology* ; Bone and Bones/injuries* ; Tendon Injuries

Objective:To investigate the role of RNA m6A methylation in mediating cerebellar dysplasia through analyzing the phenotypes of the mouse cerebella and the expression of several key m6A regulators upon hypobaric hypoxia treatment.Methods:Five-day old C57/BL6 mice were exposed to hypobaric hypoxia for 9 days. The status of mouse cerebellar development was analyzed by comparing the body weights, brain weights and histological features. Immunostaining of cell-type-specific markers was performed to analyze the cerebellar morphology. Real-time PCR, Western blot and immunohistochemical staining were performed to detect the expression of key m6A regulators in the mouse cerebella.Results:Compared with the control, the body weights, brain weights and cerebellar volumes of hypobaric hypoxic mice were significantly reduced ( P<0.01). The expression of specific markers in different cells, including NeuN (mature neuron), Calbindin-D28K (Purkinje cell) and GFAP (astrocyte), was decreased in hypobaric hypoxic mouse cerebella ( P<0.01), accompanied with disorganized cellular structure. The expression of methyltransferase METTL3 was significantly down-regulated in the cerebella of hypobaric hypoxic mice ( P<0.05). Conclusions:Hypobaric hypoxia stimulation causes mouse cerebellar dysplasia, with structural abnormalities in mature granular neurons, Purkinje cells and astrocytes. Expression of METTL3 is decreased in hypobaric hypoxic mice cerebellum compared with that of normobaric normoxic mice, suggesting that its mediated RNA m6A methylation may play an important role in hypobaric hypoxia-induced mouse cerebellar dysplasia.

Objective:To investigate the role of RNA m6A reader YTHDF2 in neurodegeneration of the aged mice.Methods:Eighteen 18-month-old control C57BL/6 mice and 22 Ythdf2 conditional knockout (cKO) mice of the same age (that exhibited significant aging characteristics) were used. Five pairs of mice were used for morphological analysis. Thirteen control mice and 17 cKO mice were used for behavioral experiments. Immunofluorescence analysis was performed to detect the expression of YTHDF2 in the brains of 18-month-old C57BL/6 mice. After establishing the neural progenitor cell-specific knockout mice of Ythdf2, their phenotypes were analyzed through comparison of body weight, brain weight and H&E staining. Subsequently, immunohistochemistry and immunofluorescence analyses were used to detect the expression of various neural cell-specific markers in the aged control mice and Ythdf2 cKO mice. Finally, behavioral tests, including the open field test, new object recognition, and water maze, were used to assess the levels of anxiety, depression, learning and memory abilities.Results:Immunofluorescence staining showed that YTHDF2 was mainly expressed in the neurons. Compared with the age-matched control mice, there was no significant change in the body weight of the Ythdf2 cKO mice, but the brain weight decreased significantly ( P<0.05). The immunostaining showed that Ythdf2 cKO mice had fewer neurons, fewer astrocytes with defective morphology, more microglia and activation of microglia ( P<0.05). Behavioral tests showed that the aged Ythdf2 cKO mice exhibited impaired movement, learning and memory abilities ( P<0.05). Conclusions:YTHDF2 is mainly expressed in the neurons of the aged brain. Conditional knockout of Ythdf2 causes quantitative and structural abnormalities in hippocampal neuronal cells, and impairs motor ability and learning and memory of the aged mice, suggesting that YTHDF2 plays an important role in neurodegeneration of the aged mice.

OBJECTIVE: To investigate the short-term effectiveness of transverse antecubital incision in the treatment of failed closed reduction of Gartland type Ⅲ supracondylar humeral fractures (SHFs) in children. METHODS: Between July 2020 and April 2022, 20 children with Gartland type Ⅲ SHFs who failed in closed reduction were treated with internal and external condylar crossing Kirschner wire fixation through transverse antecubital incision. There were 9 boys and 11 girls with an average age of 3.1 years (range, 1.1-6.0 years). The causes of injuries were fall in 12 cases and fall from height in 8 cases. The time from admission to operation ranged from 7 to 18 hours, with an average of 12.4 hours. The healing of the incision and the occurrence of complications such as nerve injury and cubitus varus were observed after operation; the elbow flexion and extension range of motion after removing the gypsum, after removing the Kirschner wire, and at last follow-up were recorded and compared, as well as the elbow flexion and extension and forearm rotation range of motion at last follow-up between healthy and affected sides; the Baumann angle was measured on the X-ray film, and the fracture healing was observed. At last follow-up, the effectiveness was evaluated according to the Flynn elbow function evaluation criteria. RESULTS: All incisions healed by first intention, and there was no skin necrosis, scar contracture, ulnar nerve injury, and cubitus varus. Postoperative pain occurred in the radial-dorsal thumb in 2 cases. The gypsum was removed and elbow flexion and extension exercises were started at 2-4 weeks (mean, 2.7 weeks) after operation, and the Kirschner wire was removed at 4-5 weeks (mean, 4.3 weeks). All the 20 patients were followed up 6-16 months, with an average of 12.4 months. The fracture healing time was 4-5 weeks, with an average of 4.5 weeks, and there was no complication such as delayed healing and myositis ossificans. The flexion and extension range of motion of the elbow joint gradually improved after operation, and there were significant differences between the time after removing the gypsum, after removing the Kirschner wire, and at last follow-up ( P<0.017). There was no significant difference in the flexion and extension of the elbow joint and the forearm rotation range of motion between the healthy and affected sides at last follow-up ( P>0.05). There was no significant difference in Baumann angle between the time of immediate after operation, after removing the Kirschner wire, and at last follow-up ( P>0.05). According to Flynn elbow function evaluation standard, 16 cases were excellent and 4 cases were good, the excellent and good rate was 100%. CONCLUSION The treatment of Gartland type Ⅲ SHFs in children with failed closed reduction by internal and external condylar crossing Kirschner wire fixation through transverse antecubital incision has the advantages of complete soft tissue hinge behind the fracture for easy reduction and wire fixation, small incision, less complications, fast fracture healing, early functional recovery, reliable reduction and fixation, and can obtain satisfactory results.
Male ; Female ; Humans ; Child ; Child, Preschool ; Calcium Sulfate ; Humerus ; Humeral Fractures/surgery* ; Plastic Surgery Procedures ; Fracture Fixation, Internal/methods* ; Bone Wires ; Fracture Healing ; Treatment Outcome ; Range of Motion, Articular

Objective:To survey and supervise the risk of infection control and radiation safety in the radiological diagnostic workplace for COVID-19, and provide data support for the safety protection of radiographers and related staff.Methods:4 emergency hospitals for COVID-19 including 2 makeshift hospitals, module hospital and brick pattern hospital in Hubei province were performed for testing and evaluation of imaging performance and radiological protection for the 8 new installed CT scanners and places according to the national standards of WS 519-2019 and GBZ 130-2013. The infection control safety factors such as the layout of the equipment room were monitored and investigated. Two COVID-19 designated hospitals including general hospital and infectious disease specialized hospital were selected to carry out field investigation and sampling of environmental biological samples for 4 CT rooms. Then the samples were detected for the nucleic acid of novel coronavirus. The results of radiodiagnostic workplace overall arrangement, infection prevention and the nucleic acid testing were analyzed, and the biological safety reliability and risk point were evaluated.Results:The indicators of imaging performance and radiation protection for 8 CT scanners in emergency hospitals could meet the requirements of national standards.Each of 2 makeshift hospitals had 3 CT rooms with the area of 38.8 m 2 and 4 mm Pb equivalent thickness of protective shielding. The CT rooms in module hospital and brick pattern hospital were 20.0 m 2, and 35.8 m 2 in areas, with 4 mm Pb equivalent and 3 mm Pb equivalent thickness of protection shielding, respectively. The 8 radiological diagnostic workplaces of the emergency hospitals were designed and constructed based on " three zones with two passage ways" . The result of the nucleic acid test indicated that the positive samples were found at the multiple sites such as scanning bed, internal of gantry and ground touched by patients in CT scanning room. The areas such as console panel and ground were risked of pollution by the virus infected hands and feet of radiographers. In addition, the similar positive samples were found in the areas in scanning room with no touch of patients, such as observation window and air outlet. Conclusions:8 CT scanners and rooms in 4 emergency hospitals basically meet the requirements of imaging performance and radiation protection. The disinfection of COVID-19 radiodiagnostic workplace should be standardized.

Objective: To investigate the expression and potential role of heterogeneous nuclear ribonucleo-protein A2B1 (HNRNPA2B1) in mouse cerebellar development and the significance of HNRNPA2B1 in human medulloblastoma. Methods: The data of HNRNPA2B1 RNA expression in mouse and human cerebella were obtained from databases. Western blot and immunohistochemical staining were performed to detect the protein level of HNRNPA2B1 in mouse cerebella at different ages. The expression level of HNRNPA2B1 in control human cerebellum and medulloblastoma was detected by immunohistochemical staining. m6A-IP-qPCR method was applied to confirm whether HNRNPA2B1 RNA in Daoy cells was modified with m6A.Western blot was used to detect the effect of MG132 treatment on the HNRNPA2B1 protein level in Daoy cells. Results: The level of HNRNPA2B1 protein in postnatal mouse cerebella was higher than that in adult mouse cerebella, with weak HNRNPA2B1 staining in external granular cells while strong staining in mature Purkinje cells and molecular layer. Compared with control normal human cerebella, the RNA expression level of HNRNPA2B1 increased in medulloblastoma, while immunohistochemical staining showed that the mean intensity of HNRNPA2B1 decreased in medulloblastoma. HNRNPA2B1 RNA in medulloblastoma and Daoy cells was modified by m6A. The HNRNPA2B1 protein level in Daoy cells increased upon MG132 treatment. Conclusions HNRNPA2B1 is dynamically expressed during mouse cerebellar development. Compared with normal human cerebella, HNRNPA2B1 is significantly up-regulated at transcriptional level but obviously down-regulated at translational level in medulloblastoma. These results indicate that HNRNPA2B1 may be involved in cerebellar development process and medulloblastoma tumorigenesis. The m6A methylation in HNRNPA2B1 transcript and protein ubiquitin-proteasome pathway may account for the down-regulation of HNRNPA2B1 at protein level.

Objective To investigate the expression and potential role of heterogeneous nuclear ribonucleo?protein A2B1 (HNRNPA2B1) in mouse cerebellar development and the significance of HNRNPA2B1 in human medulloblastoma. Methods The data of HNRNPA2B1 RNA expression in mouse and human cerebella were obtained from databases. Western blot and immunohistochemical staining were performed to detect the protein level of HNRNPA2B1 in mouse cerebella at different ages. The expression level of HNRNPA2B1 in control human cerebellum and medulloblastoma was detected by immunohistochemical staining. m6A?IP?qPCR method was applied to confirm whether HNRNPA2B1 RNA in Daoy cells was modified with m6A.Western blot was used to detect the effect of MG132 treatment on the HNRNPA2B1 protein level in Daoy cells. Results The level of HNRNPA2B1 protein in postnatal mouse cerebella was higher than that in adult mouse cerebella, with weak HNRNPA2B1 staining in external granular cells while strong staining in mature Purkinje cells and molecular layer. Compared with control normal human cerebella, the RNA expression level of HNRNPA2B1 increased in medulloblastoma, while immunohistochemical staining showed that the mean intensity of HNRNPA2B1 decreased in medulloblastoma. HNRNPA2B1 RNA in medulloblastoma and Daoy cells was modified by m6A. The HNRNPA2B1 protein level in Daoy cells increased upon MG132 treatment. Conclusions HNRNPA2B1 is dynamically expressed during mouse cerebellar development. Compared with normal human cerebella, HNRNPA2B1 is significantly up?regulated at transcriptional level but obviously down?regulated at translational level in medulloblastoma. These results indicate that HNRNPA2B1 may be involved in cerebellar development process and medulloblastoma tumorigenesis. The m6A methylation in HNRNPA2B1 transcript and protein ubiquitin?proteasome pathway may account for the down?regulation of HNRNPA2B1 at protein level.

Objective: To investigate the biological functions of protein phosphatase 2AC(PP2AC) in the brain, and to detect its spatio-temporal expression and its involvement in neurological disorders in the brains of mice and Alzheimer′s patients. Methods: Western blot was used to evaluate the expression level of PP2AC in different organs. Immunohistochemical staining was performed to detect the in situ expression levels of PP2AC in the brains of mice and patients, and the pathological changes were confirmed in the brains of patients with Alzheimer′s disease. Results: Among all the tested organs in adult mouse, the expression of PP2AC protein was the highest in the brain. From embryonic day 18.5 to postnatal 2-year-old mice, PP2AC exhibited spatio-temporal specific expression in the brains. Furthermore, an age-dependent increased expression in the cerebral cortex at both protein and RNA levels was observed. Compared to control group, PP2AC protein expression was lower in the frontal cortex of Alzheimer′s patients. Conclusions The spatio-temporal specific expression profiles of PP2AC in mouse brain implicate its biological significance. Its diminished expression in the frontal cortex of Alzheimer′s disease patients implies that PP2AC plays a potential role in the pathogenesis of Alzheimer′s disease.