Objective To investigate the chondrocyte proliferation and extracellular matrix biosynthesis of electrospun PCL scaffolds seeded with rabbit chondrocytes under flow perfusion culture in vitro.Methods Nonwoven PCL microfiber mats were fabricated,and contra-aperture cylindrical glass equipment as a perfusion bioreactor was designed and manufactured on our own.The experiment included peffusion culture group and static culture group.Primary chondrocytes were isolated from the knee joints of two-month-old New Zealand white rabbits and seeded into scaffolds.The scaffold-cell complexes were harvested at 3,7,and 14 days of culture for scanning electron micrograph (SEM) analysis,biochemical assay,real-time PCR and histology analysis.Results Electrospun PCL scaffolds were composed of microfibers with a diameter of 1.67±0.76 μm and pores with a diameter of 17.65±7.11 μm.SEM showed a better cell proliferation with typical morphology of chondrocytes under perfusion culture.At 7 days of culture,DNA content in perfusion culture group was higher than in static culture group.At 3,7 and 14 days of culture,compared with the static culture group,glycosaminoglycan (GAG) content and GAG/DNA ratio in perfusion culture group were higher,and the differences were statistically significant.At 14 days of culture,real-time PCR showed aggrecan and collagen type Ⅱ gene expression and collagen type Ⅱ to collagen type Ⅰ ratio were higher in perfusion culture group than in static culture group; HE and safranin O staining showed a significant cell proliferation,infiltration,as well as extracellular matrix biosynthesis in perfusion culture group.Conclusion Under flow perfusion culture,the electrospun PCL scaffolds seeded with rabbit chondrocytes can enhance chondrocyte proliferation and extracellular matrix biosynthesis,which is a promising method for cartilage tissue engineering.

ObjectiveTo explore the effect of osteoarthritis (OA) chondrocytes and normal chondrocytes on the chondrogenesis of bone marrow mesenchymal stem cells(BMSCs) in self designed co-culture system. MethodsRabbit BMSCs and chondrocytes were isolated and expanded in vitro. OA chondrocytes were harvested from the rabbit of established osteoarthritis model. We made a BMSCs-low melting agarose constructs, then put it onto the self-made 6 well plates lattice assembly for co-culture with chondrocytes. The groups were divided into Normal P0-BMSCs, Normal P3-BMSCs, OA PO-BMSCs, OA P3-BMSCs and BMSCs (control) group. At 3, 7, 14 day culture, cultured cells in all groups were collected for real-time PCR, glycosaminoglycan (GAG) content, cytoactive detection, and histological observation. ResultsType Ⅱ collagen gene expression was up-regulated in group Normal PO-BMSCs, which showed 5.1-, 7.2-, 11.2-fold increase over that of control group at 3, 7, 14 days, respectively. Type Ⅰ, Ⅱ collagen and aggrecan gene expressions were not obviously up-regulated. In group OA P3-BMSCs, type Ⅰ collagen gene expression level lower than the control group in 3, 7, 14 day. In normal PO-BMSCs, GAG content showed 2.59-fold increase over that of the control group. GAG content of group OA PO-BMSCs and control group showed no significant differences.Others groups showed significant differences in comparison with the control group(P＜0.05). Alcian stain showed positive in all groups. The normal PO-BMSCs group showed the darkest blue-stained. Conclusion Rabbit normal PO chondrocytes and rabbit OA P0 chondrocytes significantly enhanced chondrogenic differentiation of rabbit BMSCs. The secreted morphogens of the rabbit normal P3 chondrocytes and rabbit OA P3 chondrocytes do not have a significant effect on chondrogenic differentiation of rabbit BMSCs.

Bone is a load-bearing organ in human body. Fatigue damage occurs readily at the modest loads to which bone is subjected during its habitual physiological usage. Even bone fracture may occur during vigorous activity. The nature of fatigue damage is that in bone there are very fine microcracks which are smaller than typical microcracks, and may occur at the level of hydroxyapatite crystals. But bone can repair microdamage by bone remodeling. Osteocytes play an important role of signaling during bone remodeling. Some researchers attempted to describe the process of bone fatigue damage and repair by mathematic, mechanical models in order to understand it well and to apply it well in clinical practice.
Animals ; Bone Remodeling ; physiology ; Bone Resorption ; pathology ; physiopathology ; Bone and Bones ; cytology ; injuries ; physiology ; Fractures, Stress ; pathology ; physiopathology ; Humans ; Models, Biological ; Stress, Mechanical

From the visual angle of mechanics, bone remodelling plays an important role in adapting to load environment and repairing microcracks. In order to describe the process of bone remodelling explicitly, we introduced a bone remodelling model representing the biological features of damage/repair in bone. Based on Basic Multicellular Units (BMUs), the model embodies not only the mechano-transduction of osteocytes' response to mechanical stimuli, but also the biological process of the randomly ocurring microcracks that are resorbed by osteoclasts and then refilled by osteoblasts. A 2-D trabecular bone finite element model was used as an initial configuration in the research. The developments in bone microstructure and material properties have been monitored in the course of 10 simulated years. The conclusions are: (1) Initially, trabecular bone changes prominently, but it tends to be stable later on; (2) The material properties of trabecular bone in compression are much better than in tension.
Biomechanical Phenomena ; Bone Remodeling ; physiology ; Bone and Bones ; injuries ; pathology ; physiology ; Humans ; Models, Biological ; Stress, Mechanical ; Wound Healing

Objective:To analyze the distribution of TCM syndrome elements and syndromes in patients with hypertension with insomnia (HWI) in the real world.Methods:A cross-sectional study and retrospectively enrolled. The positive symptoms and TCM syndrome type entries of 359 patients with HWI who were collected from Henan Integrated Medicine Hospital,Henan Provincial People's Hospital,the First Affiliated Hospital of Henan University of Chinese Medicine from December 2020 to August 2022 were retrospectively studied. Based on factor analysis dimension reduction and systematic cluster analysis, the TCM syndrome elements and potential syndrome types of patients were summarized. The Latern 5.0 software was used to establish a latent structure model and comprehensive clustering based on the mountain climbing method (LTM-EAST) algorithm, and analyze and judge the common syndrome types, providing a basis for proposing the clinical common syndrome types of this disease.Results:Factor analysis extracted 14 common factors, and the cumulative contribution rate was 63.254%. Among the 36 symptom variables with frequency ≥ 70, more than half of the patients with hypertension and insomnia were upset, irritable, less sleepy, dreamy, dizzy, palpitations, stuffy chest, dry mouth, easy to wake up, and tired. The tongue color was mainly light red tongue and red tongue. The tongue is mainly thin and greasy. The first three pulse conditions are string pulse, number pulse and slippery pulse. The disease location and syndrome elements of hypertension with insomnia were mainly liver (52.09%), heart (33.43%), spleen (26.46%) and kidney (23.68%); The disease syndrome elements are mainly phlegm dampness (34.54%), yin deficiency (29.25%), heat (fire) (25.35%), and qi stagnation (25.07%). Ten syndrome types are obtained by frequency statistics, nine syndrome types are obtained by factor clustering, and seven syndrome types are inferred by implicit structure clustering. Among the syndrome types inferred by the above three methods, there are seven syndrome types that recur at least twice, which can be identified as the common syndrome type of hypertension with insomnia.Conclusions:The common clinical symptoms of HWI are upset and irritable, less sleep, more dreams, dizziness, palpitations, stuffy chest, dry mouth, easy to wake up, mental fatigue and body tiredness. The disease location and syndrome elements are mainly in liver, heart, spleen and kidney. The disease mainly involves phlegm dampness, yin deficiency, heat and qi stagnation. The common clinical syndrome types are liver depression transforming fire type, yin deficiency and yang hyperactivity type, phlegm dampness intrinsic type, yin deficiency and internal heat type, heart and gallbladder qi deficiency type, heart and spleen deficiency type, and heart kidney disjunction type.

In order to study the mechanical behavior of degeneration and nucleotomy of lumbar intervertebral disc, compression experiments with porcine lumbar intervertebral discs were carried out. The lumbar intervertebral discs with trypsin-treated and nucleus nucleotomy served as the experimental group and the normal discs as the control group. Considering the effects of load magnitude and loading rate, the relationship between stress and strain, instantaneous elastic modulus and creep property of intervertebral disc were obtained. The creep constitutive model was established. The results show that the strain and creep strain of the experimental group increase significantly with the increase of compression load and loading rate, whereas the instantaneous elastic modulus decreases obviously, compared with the control group. It indicates that the effect of load magnitude and loading rate on load-bearing capacity of intervertebral disc after nucleotomy is larger obviously than that of normal disc. The creep behavior of the experimental group can be still predicted by the Kelvin three-parameter solid model. The results will provide theoretical foundation for clinical treatment and postoperative rehabilitation of intervertebral disc disease.
Animals ; Biomechanical Phenomena ; Intervertebral Disc ; physiology ; surgery ; Lumbar Vertebrae ; Stress, Mechanical ; Swine ; Weight-Bearing

During coronavirus disease 2019 epidemic, the treatment of severe trauma has been impacted. The Consensus on emergency surgery and infection prevention and control for severe trauma patients with 2019 novel corona virus pneumonia was published online on February 12, 2020, providing a strong guidance for the emergency treatment of severe trauma and the self-protection of medical staffs in the early stage of the epidemic. With the Joint Prevention and Control Mechanism of the State Council renaming "novel coronavirus pneumonia" to "novel coronavirus infection" and the infection being managed with measures against class B infectious diseases since January 8, 2023, the consensus published in 2020 is no longer applicable to the emergency treatment of severe trauma in the new stage of epidemic prevention and control. In this context, led by the Chinese Traumatology Association, Chinese Trauma Surgeon Association, Trauma Medicine Branch of Chinese International Exchange and Promotive Association for Medical and Health Care, and Editorial Board of Chinese Journal of Traumatology, the Chinese expert consensus on emergency surgery for severe trauma and infection prevention during coronavirus disease 2019 epidemic ( version 2023) is formulated to ensure the effectiveness and safety in the treatment of severe trauma in the new stage. Based on the policy of the Joint Prevention and Control Mechanism of the State Council and by using evidence-based medical evidence as well as Delphi expert consultation and voting, 16 recommendations are put forward from the four aspects of the related definitions, infection prevention, preoperative assessment and preparation, emergency operation and postoperative management, hoping to provide a reference for severe trauma care in the new stage of the epidemic prevention and control.

Patients with severe trauma require an extremely timely treatment and transfusion plays an irreplaceable role in the emergency treatment of such patients. An increasing number of evidence-based medicinal evidences and clinical practices suggest that patients with severe traumatic bleeding benefit from early transfusion of low-titer group O whole blood or hemostatic resuscitation with red blood cells, plasma and platelet of a balanced ratio. However, the current domestic mode of blood supply cannot fully meet the requirements of timely and effective blood transfusion for emergency treatment of patients with severe trauma in clinical practice. In order to solve the key problems in blood supply and blood transfusion strategies for emergency treatment of severe trauma, Branch of Clinical Transfusion Medicine of Chinese Medical Association, Group for Trauma Emergency Care and Multiple Injuries of Trauma Branch of Chinese Medical Association, Young Scholar Group of Disaster Medicine Branch of Chinese Medical Association organized domestic experts of blood transfusion medicine and trauma treatment to jointly formulate Chinese expert consensus on blood support mode and blood transfusion strategies for emergency treatment of severe trauma patients ( version 2024). Based on the evidence-based medical evidence and Delphi method of expert consultation and voting, 10 recommendations were put forward from two aspects of blood support mode and transfusion strategies, aiming to provide a reference for transfusion resuscitation in the emergency treatment of severe trauma and further improve the success rate of treatment of patients with severe trauma.