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Background: The meniscus is one of the most commonly injured parts of the body, and meniscal healing is difficult. Hypothesis: Kartogenin (KGN) induces tendon stem cells (TSCs) to differentiate into cartilage cells in vitro and form meniscus-like tissue in vivo. A damaged meniscus can be replaced with a KGN-treated autologous tendon graft. Study Design: Controlled laboratory study. Methods: In the in vitro experiments, TSCs were isolated from rabbit patellar tendons and cultured with various concentrations of KGN, from 0 to 1000 µM. The effect of KGN on the chondrogenesis of TSCs in vitro was investigated by histochemical staining and quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR). The in vivo experiments were carried out on 6 New Zealand White rabbits by removing a meniscus from the rabbit knee and implanting an autologous tendon graft treated with KGN or saline. The meniscus formation in vivo was examined by histological analysis and immune staining. Results: The proliferation of TSCs was promoted by KGN in a concentration-dependent manner. Both histochemical staining and qRT-PCR showed that the chondrogenic differentiation of TSCs was increased with KGN concentration. After 3 months of implantation, the tendon graft treated with KGN formed a meniscus-like tissue with a white and glistening appearance, while the saline-treated tendon graft retained tendon-like tissue and appeared yellowish and unhealthy. Histochemical staining showed that after 3 months of implantation, the KGN-treated tendon graft had a structure similar to that of normal meniscus. Many cartilage-like cells and fibrocartilage-like tissues were found in the KGN-treated tendon graft. However, no cartilage-like cells were found in the saline-treated tendon graft after 3 months of implantation. Furthermore, the KGN-treated tendon graft was positively stained by both anti–collagen type I and type II antibodies, but the saline-treated tendon graft was not stained by collagen type II. Conclusion: The findings indicated that KGN can induce the differentiation of TSCs into cartilage-like cells in vitro and in vivo. The results suggest that KGN-treated tendon graft may be a good substitute for meniscal repair and regeneration. Clinical Relevance: This study revealed the direct effects of KGN on the chondrogenic differentiation of TSCs in vitro and in vivo. A KGN-treated autologous tendon graft induced formation of a meniscus-like tissue in vivo. This study provides a new cartilage regenerating technology for the treatment of damaged meniscus. [ABSTRACT FROM AUTHOR]

As one of the typical farmland ecosystems, tea gardens are of vital importance in China. The purpose of this study was to quantify the dynamic of soil properties, soil microbial diversity, and nematodes, as affected by various cover crop patterns in a Tanjiawan tea garden in Hubei Province, China. Four cover crop patterns were established as following: naturally covered of bare land and mixed planting with two species, four species, and eight species. The results revealed that soil organic matter, pH, and total phosphorous content were significantly related to cover crop patterns. The number of nematodes increased with cover crop diversity, and the percentage of plant parasitic nematodes in cover crop treatments was lower than in naturally covered bare land. A higher diversity of cover crops increased the number of bacterivores and fungivores, thereby enhancing the bacterial decomposition pathway of soil organic matter. Both soil nematodes and microbial communities showed significant seasonal changes under different cover crop patterns. The soil food webs were more stable and mature under cover crops with two species and four species. Combined with the results of a structural equation model, we found that soil properties, characterized by the total nitrogen, available phosphorus, NO 3 - -N, and soil organic matter, were significantly correlated with soil nematodes and microbial communities. In addition, acterivores and plant parasites were significantly negatively correlated with omnivores/predators. Our results implied that soil properties and seasonal changes influence the relationships between cover crops, soil nematodes, and microbial communities. These findings provide a theoretical basis for future studies on interactions between soil properties, soil microorganisms, and nematodes in tea gardens.

Purpose: Pneumatic tourniquets are used in total knee arthroplasty (TKA) for surgical field visualization and improved cementation; however, their use is controversial. This study aimed to assess the effects of tourniquet application on enhanced recovery post-TKA., Methods: A prospective randomized single-blinded trial assessed tourniquet's effects on postoperative pain, swelling, and early outcome in TKA. One-hundred and two patients with knee osteoarthritis were randomized to full-course (FC) and second half-course (SHC) application ( n = 51/group). Tumor necrosis factor-alpha (TNF-α), C-C motif chemokine ligand 2(CCL-2), pentraxin-3 (PTX-3), prostaglandin E-2 (PGE-2), superoxide dismutase-1 (SOD-1), and myoglobin (Mb) were assessed by enzyme-linked immunosorbent assay, while the visual analog scale (VAS), range of motion (ROM), and thigh circumference growth rate were recorded., Results: Average tourniquet duration significantly differed between the SHC (37.5 ± 5.1 min) and FC (66.4 ± 7.2 min) groups ( p < 0.01); VAS and thigh circumference growth rate in the SHC group were much lower compared with the FC group, while ROM was higher within 48 h of tourniquet removal ( p < 0.01). Blood TNF-α, PTX3, CCL2, PGE2, SOD-1, and Mb were lower in the SHC group than the FC group ( p < 0.01). Additionally, intraoperative blood loss was significantly elevated in the SHC group than the FC group ( p < 0.01), with lower postoperative blood loss in the drain ( p = 0.001). Postoperative drainage volume was reduced in the SHC group compared with the FC group ( p < 0.01); five and two patients in the FC and SHC groups required blood transfusion, respectively ( p = 0.025). Hospital stay tended to be shorter in the SHC group ( p = 0.023), and no tourniquet-related complications were recorded., Conclusion: Improved therapeutic outcome was observed in the SHC group, indicating patients should routinely undergo TKA with SHC tourniquet application.

Primary frozen shoulder (PFS) is a common condition of uncertain etiology that is characterized by shoulder pain and restriction of active and passive glenohumeral motions. The pathophysiology involves chronic inflammation and fibrosis of the joint capsule. Single nucleotide polymorphisms (SNPs) at IL-1β , MMP3 , TGF-β1 , and GDF5 have been associated with risk of a variety of inflammatory diseases; however, no studies have examined these SNPs with susceptibility to PFS. We investigated allele and genotype frequencies of rs1143627 at IL-1β , rs650108 at MMP-3 , rs1800469 at TGF-β1 , and rs143383 at GDF5 in 42 patients with PFS and 50 healthy controls in a Chinese Han population. Serum samples from both cohorts were evaluated to determine the expression levels of IL-1 β . We found that the IL-1β rs1143627 CC genotype was associated with a decreased risk of PFS compared to the TT genotype ( P = 0.022) and that serum IL-1 β was expressed at a significantly higher level in the PFS cohort compared to that found in the control group ( P < 0.001). Our findings indicated no evidence of an association between rs650108, rs1800469, or rs143383 and PFS. IL-1 β is associated with susceptibility to PFS and may have a role in its pathogenesis in a Chinese Han population.