Gut microbiota metabolic pathways: Key players in knee osteoarthritis development.

OBJECTIVE: To confirm the causality of gut microbiota pathway abundance and knee osteoarthritis (KOA). METHODS: Microbial metabolic pathways were taken as exposures, with data from the Dutch Microbiome Project (DMP). Data on KOA from the UK Biobank were utilized as endpoints. In addition, we extracted significant and independent single nucleotide polymorphisms as instrumental variables. Two-sample Mendelian randomization (MR) analysis was applied to explore the causal relationship between gut microbiota pathway abundance and KOA, and MR-Egger and weighted median were used as additional validation of the MR results. Meanwhile, Cochran Q, MR-Egger intercept, MR-PRESSO, and leave-one-out were used to perform sensitivity analyses on the MR results. RESULTS: MR results showed that enterobactin biosynthesis, diacylglycerol biosynthesis I, Clostridium acetobutylicum acidogenic fermentation, glyoxylate bypass and tricarboxylic acid cycle were the risk factors for KOA. (OR = 1.13,95%CI = 1.04-1.23;OR = 1.12,95%CI = 1.04-1.20;OR = 1.14,95%CI = 1.04-1.26; OR = 1.06,95%CI = 1.00-1.12) However, adenosylcobalamin salvage from cobinamide I, hexitol fermentation to lactate formate ethanol and acetate, purine nucleotides degradation II aerobic, L tryptophan biosynthesis and inosine 5 phosphate biosynthesis III pathway showed significant protection against KOA. (OR = 0.93,95%CI = 0.86-1.00;OR = 0.94,95%CI = 0.88-1.00;OR = 0.91,95%CI = 0.86-0.97;OR = 0.95,95%CI = 0.92-0.99; OR = 0.91, 95%CI = 0.85-0.98) Further multiplicity and sensitivity analyses demonstrated the robustness of the results. CONCLUSION: Our study identified specific metabolic pathways in gut microbiota that promote or inhibit KOA, which provides the most substantial evidence-based medical evidence for the pathogenesis and prevention of KOA.

Amphiphilic Interface-Mediated Ion Doping for High Performance Organic Electrochemical Transistors with Hydrophobic Polymers.

An organic electrochemical transistor (OECT) is one of the promising devices for bioelectronics due to its high transconductance, encompassing low operation voltage, and good compatibility with aqueous conditions. Despite these advantages, the challenge of balancing ion penetration and electron transport remains a significant issue in OECTs. Herein, we present an amphiphilic interface modification strategy to successfully prepare OECTs in aqueous conditions based on a high-mobility hydrophobic polypyrrole derivative. An amphiphilic interface mixed with an amphiphilic polymer and the active layer markedly promotes ion penetration and results in a significant improvement in performance, with the switch time reduced from several seconds to nearly 100 ms and the transconductance increased by an order of magnitude. The high-performance OECTs fabricated by this method show promising applications in high-performance neuromorphic devices and ECG recording in advancing the field of electrochemical transistors.

Correlation between environmental nickel exposure and the development of arthritis: A large-sample cross-sectional investigation.

BACKGROUND: Nickel is a common metallic element in orthopedic implanted devices and living environment exposures. It is associated with varieties of diseases. The purpose of this investigation was to explore the correlation between nickel exposure and the prevalence of arthritis. METHODS: Data were obtained from the National Health and Nutrition Examination Survey (NHANES) database from 2017 to 2018. Multivariate logistic regression was utilized to analyze the relationship between urinary nickel levels and arthritis. In addition, hierarchical modeling further explored the interactions and trends between urinary nickel levels and arthritis. Propensity score matching (PSM) method was used to reduce the effect of confounders. Additionally, restricted cubic spline curve (RCS) was used to assess the possible nonlinear association between urinary nickel and arthritis. RESULTS: The investigation was comprised of 139 arthritis patients and 547 healthy participants. After correction by PSM, there was a positive correlation between arthritis and Nickel exposure levels. The risk of developing arthritis was significantly increased when nickel exposure levels were in the Q4 interval (OR=2.25, 95 % CI=1.03-5.02). When stratified by age and sex, nickel exposure was significantly and positively associated with arthritis in the subgroup aged over 65 years. (OR=2.78,95 %CI=1.20-6.46). Also, the difference between nickel exposure and arthritis was significant in the different gender subgroups (interaction P<0.05). Restricted cubic spline (RCS) results showed a significant linear association between nickel exposure levels and arthritis. In addition, there was a non-linear association between nickel exposure and arthritis across gender and age subgroups. CONCLUSION: A significant positive association between nickel exposure levels and arthritis was showed by the experimental data. Controlling the use of nickel-containing medical prostheses and reducing exposure to nickel-containing daily necessity could help to slow the onset of arthritis.

[Simultaneous determination of seven quaternary ammonium compounds in frozen food by ultra performance liquid chromatography-tandem mass spectrometry combined with modified QuEChERS method].

Quaternary ammonium compounds (QACs) are a class of cationic surfactants that can be used as the main active ingredient of disinfectants. The increased use of QACs is concerning as exposure from inhalation or ingestion to these compounds that has been associated with adverse effects on the reproductive and respiratory systems. Humans are exposed to QACs primarily by food consumption and inhalation of air. QAC residues pose significant threats to public health. Given the importance of assessing potential residue levels for QACs in food, therefore, a method was developed for the simultaneous detection of six common QACs and one emerging QAC (Ephemora) in frozen food by ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) coupled with the modified QuEChERS method. The main factors governing the response, recovery, and sensitivity of the method, including extraction solvents, types and dosages of adsorbents, apparatus conditions, and mobile phases, were optimized in the course of sample pretreatment and instrument analysis. QAC residues in frozen food were extracted using 20 mL methanol-water (90∶10, containing 0.5% formic acid) for 20 min by the vortex shock method. The mixture was ultrasonicated for 10 min and centrifuged at 10000 r/min for 10 min. A 1-mL aliquot of the supernatant was transferred to a new tube and purified using 100 mg of PSA adsorbents. After mixing and centrifugation at 10000 r/min for 5 min, the purified solution was analyzed. Target analytes were separated on an ACQUITY UPLC BEH C8 chromatographic column (50 mm×2.1 mm, 1.7 µm) at a column temperature of 40 ℃ and a flow rate of 0.3 mL/min. The injection volume was 1 µL. Gradient elution was performed using methanol and 5 mmol/L ammonium acetate solution as the mobile phases. Multiple reaction monitoring (MRM) was conducted in the positive electrospray ionization (ESI+) mode. The matrix-matched external standard method was used to quantify seven QACs. The optimized chromatography-based method completely separated the seven analytes. Good linear relationships were obtained for the seven QACs in the range of 0.1-100.0 ng/mL. The correlation coefficient (r2) ranged from 0.9971 to 0.9983. The limits of detection and limits of quantification ranged from 0.5 to 1.0 µg/kg and 1.5 to 3.0 µg/kg, respectively. Accuracy and precision were determined by spiking salmon and chicken samples with 3.0, 10.0, and 100.0 µg/kg of analytes, in compliance with the current legislation, with six replicates per determination. The average recoveries of the seven QACs ranged from 65.4% to 101%. The relative standard deviations (RSDs) were between 0.64% and 16.8%. Matrix effects of the analytes were between -27.5% and 33.4% in salmon and chicken samples after purifying using PSA. The developed method was applied to the determination of seven QACs in rural samples. QACs were detected in only one sample; the level did not exceed European Food Safety Authority specified residue limit standards. The detection method has high sensitivity, good selectivity and stability, and the results are accurate and reliable. It is suitable for the simultaneous rapid determination of seven QAC residues in frozen food. The results provide valuable information for future risk assessment studies targeting this class of compounds.

Single-cell RNA sequencing analysis reveals the relationship of bone marrow and osteopenia in STZ-induced type 1 diabetic mice.

INTRODUCTION: Type 1 diabetes (T1D) is a multifactorial autoimmune disease. Broad knowledge about the genetics, epidemiology and clinical management of T1D has been achieved, but understandings about the cell varieties in the bone marrow during T1D remain limited. OBJECTIVES: We aimed to present a profile of the bone marrow cells and reveal the relationship of bone marrow and osteopenia in streptozotocin (STZ)-induced T1D mice. METHODS: The whole bone marrow cells from the femurs and tibias of healthy (group C) and STZ-induced T1D mice (group D) were collected for single-cell RNA sequencing analysis. Single-cell flow cytometry and immunohistochemistry were performed to confirm the proportional changes among bone marrow neutrophils (BM-neutrophils) (Cxcr2+, Ly6g+) and B lymphocytes (Cd19+). X-ray and micro-CT were performed to detect bone mineral density. The correlation between the ratio of BM-neutrophils/B lymphocytes and osteopenia in STZ-induced T1D mice was analyzed by nonparametric Spearman correlation analysis. RESULTS: The bone marrow cells in groups C and D were divided into 12 clusters, and 249 differentially expressed genes were found. The diversity of CD45+ immune cells between groups C and D were greatly affected: the proportion of BM-neutrophils showed a significant increase while the proportion of B lymphocytes in group D showed a significant decrease. X-ray and micro-CT analyses confirmed that osteopenia occurred in group D mice. In addition, the results of single-cell flow cytometry and correlation analysis showed that the ratio of BM-neutrophils/B lymphocytes negatively correlated with osteopenia in STZ-induced T1D mice. CONCLUSION: A single-cell RNA sequencing analysis revealed the profile and heterogeneity of bone marrow immune cells in STZ-induced T1D mice for the first time. The ratio of BM-neutrophils/B lymphocytes negatively correlated with osteopenia in STZ-induced T1D mice, which may enhance understanding for treating T1D and preventing T1D-induced osteopenia.

α2-macroglobulin-rich serum as a master inhibitor of inflammatory factors attenuates cartilage degeneration in a mini pig model of osteoarthritis induced by "idealized" anterior cruciate ligament reconstruction.

Post-traumatic osteoarthritis is a special type of osteoarthritis and a common disease, with few effective treatments available. α2-Macroglobulin (α2M) is important to chondral protection in post-traumatic osteoarthritis. However, its injection into xenogeneic joint cavities involves safety hazards, limiting clinical applications. Exploring serum α2M-enriching strategies and the therapeutic effect and mechanism of α2M-rich serum (α2MRS) autologous joint injection to treat post-traumatic osteoarthritis has significant value. In the present study, a unique filtration process was used to obtain α2MRS from human and mini pig serum. We evaluated the potential of α2MRS in protecting against post-surgery cartilage degeneration. We identify the potential of α2MRS in reducing the expression of inflammatory cytokines and factors that hasten cartilage degeneration in post-operative conditions leading to post-traumatic osteoarthritis. The potential of α2MRS was analyzed in interleukin-1ß induced human chondrocytes and mini pig models. In the chondrocyte model, α2MRS significantly promoted human chondrocyte proliferation and reduced apoptosis and chondrocyte catabolic cytokine gene transcription and secretion. The anterior cruciate ligament autograft reconstruction model of mini pigs was randomized into groups, operated on, and injected with α2MRS or saline. The results showed that α2MRS injection significantly suppressed the levels of inflammatory factors, improved gait, and showed significantly lower cartilage degeneration than the groups that did not receive α2MRS injections. This study highlights the chondroprotective effects of α2MRS, elucidated its potential applications against cartilage degeneration, and could provide a basis for the clinical translation of α2MRS.

The versatile roles of odontogenic ameloblast-associated protein in odontogenesis, junctional epithelium regeneration and periodontal disease.

Junctional epithelium (JE) is a vital epithelial component which forms an attachment to the tooth surface at the gingival sulcus by the adhesion of protein complexes from its basal layer. Disruption of the JE is associated with the development of gingivitis, periodontal disease, and alveolar bone loss. Odontogenic ameloblast-associated (ODAM) is comprised of a signal peptide and an ODAM protein with 12 putative glycosylation sites. It is expressed during odontogenesis by maturation stage ameloblasts and is incorporated into the enamel matrix during the formation of outer and surface layer enamel. ODAM, as a secreted protein which is accumulated at the interface between basal lamina and enamel, mediates the adhesion of the JE to the tooth surface; and is involved with extracellular signalling of WNT and ARHGEF5-RhoA, as well as intracellular signalling of BMP-2-BMPR-IB-ODAM. ODAM is also found to be highly expressed in salivary glands and appears to have implications for the regulation of formation, repair, and regeneration of the JE. Bioinformatics and research data have identified the anti-cancer properties of ODAM, indicating its potential both as a prognostic biomarker and therapeutic target. Understanding the biology of ODAM will help to design therapeutic strategies for periodontal and dental disorders.

Progress of 3D Printing Techniques for Nasal Cartilage Regeneration.

Once cartilage is damaged, its self-repair capacity is very limited. The strategy of tissue engineering has brought a new idea for repairing cartilage defect and cartilage regeneration. In particular, nasal cartilage regeneration is a challenge because of the steady increase in nasal reconstruction after oncologic resection, trauma, or rhinoplasty. From this perspective, three-dimensional (3D) printing has emerged as a promising technology to address the complexity of nasal cartilage regeneration, using patient's image data and computer-aided deposition of cells and biomaterials to precisely fabricate complex, personalized tissue-engineered constructs. In this review, we summarized the major progress of three prevalent 3D printing approaches, including inkjet-based printing, extrusion-based printing and laser-assisted printing. Examples are highlighted to illustrate 3D printing for nasal cartilage regeneration, with special focus on the selection of seeded cell, scaffolds and growth factors. The purpose of this paper is to systematically review recent research about the challenges and progress and look forward to the future of 3D printing techniques for nasal cartilage regeneration.Level of Evidence III This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews, and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies, and Experimental Studies. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors https://www.springer.com/00266 .

An accurate method for locating the joint line during revision total knee arthroplasty: A radiologic study in the Chinese population.

BACKGROUND: The systems for precisely locating the joint line during primary and revision total knee arthroplasty are still controversial, and they should be better evaluated in the Chinese population. METHODS: A total of 451 standard anteroposterior knee radiographs from 451 healthy Chinese people (283 males and 168 females, the average age of 33.26 years, range 20-50 years) were included to measure the femoral width (FW) and the distances from the adductor tubercle (AT), the medial epicondyle (ME), the lateral epicondyle (LE), and the fibular head (FH) to the joint line (JL). Correlation between FW and distances from landmarks to the joint line was evaluated using Pearson correlation coefficient, and the ratios of ATJL, MEJL, LEJL, FHJL to FW were calculated. RESULTS: The average distances from the AT, the ME, the LE, the FH to the JL were 49.4 ± 5.0 mm, 28.3 ± 3.1 mm, 26.9 ± 2.9 mm, 20.0 ± 4.0 mm, respectively. An excellent linear correlation was found between FW and the distance from AT to the joint line (R = 0.836, R2 = 0.698); it was more reliable than the LE (R = 0.686, R2 = 0.471) and the ME (R = 0.672, R2 = 0.452). The average ratios of ATJL/FW, MEJL/FW, LEJL/FW were 0.553, 0.317, and 0.302, respectively. There were significant differences between our results and the studies based on the Western people. CONCLUSION: The AT can be used as a reliable landmark to locate the JL precisely by the formula (ATJL = 0.548 × FW in males; ATJL = 0.562 × FW in females) in the Chinese population. The LE and ME can be the second choices. Moreover, it may be better to use ratios from the research based on the same race.

Histone deacetylase 4 deletion results in abnormal chondrocyte hypertrophy and premature ossification from collagen type 2α1­expressing cells.

Histone deacetylase 4 (HDAC4) plays a vital role in chondrocyte hypertrophy and bone formation. To investigate the function of HDAC4 in postnatal skeletal development, the present study developed lineage­specific HDAC4­knockout mice [collagen type 2α1 (Col2α1)­Cre, HDAC4d/d mice] by crossing transgenic mice expressing Cre recombinase. Thus, a specific ablation of HDAC4 was performed in Col2α1­expressing mice cells. The knee joints of HDAC4fl/fl and Col2α1­Cre, HDAC4d/d mice were analyzed at postnatal day (P)2­P21 using an in vivo bromodeoxyuridine (BrdU) assay, and Safranin O, Von Kossa and whole­body staining were used to evaluate the developmental growth plate, hypertrophic differentiation, mineralization and skeletal mineralization patterns. The trabecular bone was analyzed using microcomputed tomography. The expressions of BrdU, proliferating cell nuclear antigen (PCNA), matrix metalloproteinase (MMP)­13, runt­related transcription factor (Runx)­2, osteoprotegerin (OPG), CD34, type X collagen (ColX), osteocalcin and Wnt5a were determined using immunohistochemistry, in situ hybridization (ISH) and reverse transcription­quantitative (RT­q)PCR. The results demonstrated that HDAC4­null mice (HDAC4d/d mice) were severely runted; these mice had a shortened hypertrophic zone (histopathological evaluation), accelerated vascular invasion and articular mineralization (Von Kossa staining), elevated expressions of MMP­13, Runx2, OPG and CD34 (RT­qPCR and immunohistochemistry), downregulated expression of the proliferative marker BrdU and PCNA (immunohistochemistry), increased expression of ColX and decreased expression of Wnt5a (ISH). In conclusion, chondrocyte­derived HDAC4 was responsible for regulating chondrocyte proliferation and differentiation as well as endochondral bone formation.

[Progress in the method of tibial prosthesis rotation alignment in total knee arthroplasty].

OBJECTIVE: To summarize the methods of tibial prosthesis rotation alignment in total knee arthroplasty, and provide reference for clinicians to select and further study the methods of tibial prosthesis rotation alignment. METHODS: The advantages and disadvantages of various tibial prosthesis rotation alignment methods were analyzed and summarized by referring to the relevant literature at home and abroad in recent years. RESULTS: There are many methods for tibial prosthesis rotation alignment, including reference to relevant anatomical landmarks, range of motion (ROM) technique, computer-assisted navigation, and personalized osteotomy. The inner one-third of the tibial tuberosity is a more accurate reference anatomical landmark, but the obesity, severe knee deformity and dysplasia have impacts on the precise placement of the tibial prosthesis. ROM technique do not need to refer to the anatomical landmark of the tibia, and aren't affected by landmark variation. It can be used for severe knee valgus deformity and the landmarks that are difficult to identify. However, it may cause internal rotation of tibial prosthesis. Computer- assisted navigation and personalized osteotomy can achieve more accurate alignment in sagittal, coronal, and rotational alignment of femoral prosthesis. However, due to the lack of reliable anatomical landmarkers related to tibia fixation, it is still controversial whether it can help the alignment of tibial prosthesis rotation. CONCLUSION: The surgeon should master the methods of rotation and alignment of tibial prosthesis, make preoperative plans, select appropriate alignment methods for different patients, and achieve individualization. Meanwhile, several anatomical landmarkers should be referred to properly during the operation, which can be used to detect the correct placement of tibial prosthesis and avoid large rotation error.

A global bibliometric and visualized analysis in the status and trends of subchondral bone research.

BACKGROUND: Structural and functional changes in subchondral bone have been recognized as a key factor in the development of related disease, and subchondral bone may be a new target for the treatment of osteoarthritis. The purpose of our present study is to investigate the global status and trends of subchondral bone research. METHOD: Publications related to the studies of subchondral bone from 1993 to 2018 were retrieved from the Science Citation Index-Expanded Web of Science database. The data source was studied and indexed by using bibliometric methodology. For visualized study, bibliographic coupling analysis, co-authorship analysis, co-citation analysis, co-occurrence analysis and the analysis of publication trends in subchondral bone research were conducted by VOS viewer and GraphPadPrism 5 software. RESULTS: A total of 4780 publications were included. There is an increasing trend of the relative research interests and number of publications per year globally. The cumulative number of publications about subchondral bone research followed the logistic growth model (Equation is included in full-text article.). The USA made the highest contributions to the global research with the most citations, the highest H-index, and the most total link strength, while Denmark had the highest average citation per item. The journal Osteoarthritis and Cartilage had the largest publication number. Boston University is the most contributive institution. Studies could be divided into 4 clusters: "Mechanism research", "Animal study", "Clinical study" and "Pathological features". Less efforts were put into clinical study. CONCLUSION: The number of publications about subchondral bone research would be increasing in the next years based on the current global trends. Attention should be drawn to the latest popular research, including "Mesenchymal stem-cells", "Autologous chondrocyte implantation", "Microfracture" and "Pain". Therefore, more and more efforts will be put into mechanism research on subchondral bone, which may inspire new clinical treatments for osteoarthritis and other related diseases based on subchondral bone.

Endothelial cells produce angiocrine factors to regulate bone and cartilage via versatile mechanisms.

Blood vessels are conduits distributed throughout the body, supporting tissue growth and homeostasis by the transport of cells, oxygen and nutrients. Endothelial cells (ECs) form the linings of the blood vessels, and together with pericytes, are essential for organ development and tissue homeostasis through producing paracrine signalling molecules, called angiocrine factors. In the skeletal system, ECs - derived angiocrine factors, combined with bone cells-released angiogenic factors, orchestrate intercellular crosstalk of the bone microenvironment, and the coupling of angiogenesis-to-osteogenesis. Whilst the involvement of angiogenic factors and the blood vessels of the skeleton is relatively well established, the impact of ECs -derived angiocrine factors on bone and cartilage homeostasis is gradually emerging. In this review, we survey ECs - derived angiocrine factors, which are released by endothelial cells of the local microenvironment and by distal organs, and act specifically as regulators of skeletal growth and homeostasis. These may potentially include angiocrine factors with osteogenic property, such as Hedgehog, Notch, WNT, bone morphogenetic protein (BMP), fibroblast growth factor (FGF), insulin-like growth factor (IGF), and platelet-derived growth factor (PDGF). Understanding the versatile mechanisms by which ECs-derived angiocrine factors orchestrate bone and cartilage homeostasis, and pathogenesis, is an important step towards the development of therapeutic potential for skeletal diseases.

Autografts vs Synthetics for Cruciate Ligament Reconstruction: A Systematic Review and Meta-Analysis.

To describe the outcomes of autografts and synthetics in anterior cruciate ligament (ACL) and posterior cruciate ligament (PCL) reconstruction with respect to instrumented laxity measurements, patient-reported outcome scores, complications, and graft failure risk. We searched PubMed, Cochrane Library, and EMBASE for published randomized controlled trials (RCT) and case controlled trials (CCTs) to compare the outcomes of the autografts versus synthetics after cruciate ligament reconstruction. Data analyses were performed using Cochrane Collaboration RevMan 5.0. Nine studies were identified from the literature review. Of these studies, three studies compared the results of bone-patellar tendon-bone (BPTB) and ligament augmentation and reconstruction system (LARS), while six studies compared the results of four-strand hamstring tendon graft (4SHG) and LARS. The comparative study showed no difference in Lysholm score and failure risk between autografts and synthetics. The combined results of the meta-analysis indicated that there was a significantly lower rate of side-to-side difference > 3 mm (Odds Ratio [OR] 2.46, 95% confidence intervals [CI] 1.44-4.22, P = 0.001), overall IKDC (OR 0.40, 95% CI 0.19-0.83, P = 0.01), complications (OR 2.54, 95% CI 1.26-5.14, P = 0.009), and Tegner score (OR -0.31, 95% CI -0.52-0.10, P = 0.004) in the synthetics group than in the autografts group. This systematic review comparing long-term outcomes after cruciate ligament reconstruction with either autograft or synthetics suggests no significant differences in failure risk. Autografts were inferior to synthetics with respect to restoring knee joint stability and patient-reported outcome scores, and were also associated with more postoperative complications.

DAla2GIP antagonizes H2O2-induced chondrocyte apoptosis and inflammatory factor secretion.

OBJECTIVE: To investigate the protective effects of DAla2GIP against the apoptosis and inflammatory factor secretion in H2O2-induced chondrocyte, and explore the possible mechanisms of DAla2GIP underlying its protection. METHODS: The chondrocytes were divided into the following four groups: Control, 300 µM H2O2, 100 pM DAla2GIP and 300 µM H2O2 + 100 pM DAla2GIP. The apoptosis of chondrocyte was measured by using mitochondrial membrane potential assay kit (JC-1) and TUNEL assay, the inflammatory factor secretion were assessed by ELISA assay, and the cellular and molecular mechanisms of DAla2GIP protection were investigated by using Real time-PCR, flow cytometry, Non- invasive calcium detection and western blotting techniques. RESULTS: (1) DAPla2GIP prevents apoptosis of chondrocyte induced by H2O2. (2) DAla2GIP alleviated the inflammation of chondrocyte induced by H2O2. (3) DAla2GIP prevents chondrocyte apoptosis by inhibiting calcium influx of chondrocyte and regulating expression of Bcl-2 and Caspase-3induced by H2O2. (4) DAla2GIP inhibited the H2O2 mediated inflammation by up- regulating the expressions of Sox9 and Col2a1 and inhibiting PI3K/Akt/NF-κB pathway. CONCLUSION: Our experimental results revealed that DAla2GIP prevents chondrocyte apoptosis by inhibiting calcium influx of chondrocyte and induced regulating expression of Bcl-2 and Casp ase-3by H2O2. Further, molecular biology experiments confirmed that DAla2GIP inhibited the H2O2 mediated inflammation vis up-regulating the expressions of Sox9 and Col2a1 and inhibiting PI3K/Akt/NF-κB pathway. The results demonstrate that DAla2GIP has protective properties in H2O2-induced chondrocyte injury, this finding shows that novel GIP analogues have the potential as a novel therapeutic for osteoarthritis patients.

Knockdown Indian Hedgehog (Ihh) does not delay Fibular Fracture Healing in genetic deleted Ihh mice and pharmaceutical inhibited Ihh Mice.

The objective of this study was to determine if Ihh is required for fracture healing. Fibular fracture was created in adult Col2a1-CreERT2; Ihhfl/fl mice. Ihhfl/fl mice received Tamoxifen (TM) to delete Ihh. WT mice received Cyclopamine to inhibit Hh pathway. Callus tissue properties and Ihh pathway were analyzed at 1, 2, and 3 weeks post-fracture by X-ray, micro-CT, mechanical test, RT-PCR and immunohistochemistry. Deleted Ihh was evidenced by the occurrence of growth plate closure in the Ihhfl/fl mice by X-ray 3 weeks after TM treatment. All mice showed fracture healing at 3 weeks post-operation. Histology analysis indicated that, compared to the control, cartilage area was less in fracture sites from Ihh deficient animals by either genetic deletion or drug inhibition at 1 and 2 weeks post-fracture. Ihh immunostaining and its mRNA level were diminished in the fracture callus in Ihh reduced mice. There was no significant difference in BV/TV, BMD and mechanical test. Interruption to Ihh pathway by either genetic or pharmaceutical approach didn't affect fibular fracture healing in these mice. This surprised finding implicates that the deleted Ihh does not affect fracture healing in this model.

Sphingosine-1-phosphate mediates the therapeutic effects of bone marrow mesenchymal stem cell-derived microvesicles on articular cartilage defect.

Microvesicles (MVs) are emerging as a new mechanism of intercellular communication by transferring cellular components to target cells, yet their function in disease is just being explored. However, the therapeutic effects of MVs in cartilage injury and degeneration remain unknown. We found MVs contained high levels of sphingosine-1-phosphate (S1P) compared with the original bone marrow mesenchymal stem cells (MSCs). The enrichment of S1P in MVs was mediated by sphingosine kinase 1 (SphK1), but not by sphingosine kinase 2 (SphK2). Co-culture of human chondrocytes with MVs resulted in increased proliferation of chondrocytes in vitro, which was mediated by activation of S1P receptor 1 (S1PR1) expressed on chondrocytes. Meanwhile, MVs inhibited interleukin 1 beta-induced human chondrocytes apoptosis in a dose dependent manner. Furthermore, uptake of MVs by primary cultures of human chondrocytes was mediated by CD44 expressed by MVs. Anti-CD44 antibody significantly reduced the uptake of fluorescent protein-labeled MVs by chondrocytes. Further, blocking S1P by its neutralizing antibody significantly inhibited the therapeutic effects of MVs in vivo. Taken together, MVs showed therapeutic potential for treatment of clinical cartilage injury. This therapeutic potential is due to CD44-mediated uptake of MVs by chondrocytes and the S1P/S1PR1 axis-mediated proliferative effects of MVs on chondrocytes.

HGF/Met Signaling in Cancer Invasion: The Impact on Cytoskeleton Remodeling.

The invasion of cancer cells into surrounding tissue and the vasculature is essential for tumor metastasis. Increasing evidence indicates that hepatocyte growth factor (HGF) induces cancer cell migration and invasion. A broad spectrum of mechanisms underlies cancer cell migration and invasion. Cytoskeletal reorganization is of central importance in the development of the phenotype of cancer cells with invasive behavior. Through their roles in cell mechanics, intracellular trafficking, and signaling, cytoskeleton proteins participate in all essential events leading to cell migration. HGF has been involved in cytoskeleton assembly and reorganization, and its role in regulating cytoskeleton dynamics is still expanding. This review summarizes our current understanding of the role of HGF in regulating cytoskeleton remodeling, distribution, and interactions.

[Analysis of projects received and funded in fields of emergency and intensive care medicine/trauma/burns/plastic surgery from National Natural Science Foundation of China during 2010-2013].

OBJECTIVE: To summarized the projects received and funded in the fields of emergency and intensive care medicine/trauma/burns/plastic surgery from National Natural Science Foundation of China (NSFC) during 2010-2013, put forward the thinking and perspective of this future trend in these fields. METHODS: The number of the funded project and total funding in the fields of emergency and intensive care medicine/trauma/burns/plastic surgery from NSFC during 2010-2013 had been statistical analyzed, in the meantime, the overview situation of various branches in basic research and further preliminary analysis the research frontier and hot issues have been analyzed. RESULTS: (1) The number of funded project were 581 in H15 of NSFC during 2010-2013, total funding reached to 277.13 million RMB, including 117 projects in H1511 (emergency and intensive care medicine/trauma/burns/plastic surgery and other science issue), 96 projects in H1507 (wound healing and scar), 88 projects in H1502 (multi-organ failure), 71 projects in H1505 (burn), 61 projects in H1504 (trauma). (2) The top 10 working unit for project funding in the field of emergency and intensive care medicine/trauma/burns/plastic surgery present as Third Military Medical University (70), Shanghai Jiao tong University (69), Second Military Medical University (40), Chinese PLA General Hospital (36), Forth Military Medical University (35), Zhejiang University (22), Sun Yat-Sen University (18), Southern Medical University (14), China Medical University (11), Capital Medical University (11) respectively, the number of funded project positive correlated with funding. (3) The funded research field in H15 covered almost all important organs and system injury or repair research, our scientists reached a fairly high level in some research field, for example, sepsis, trauma, repair, et al. "Sepsis" was funded 112 projects in H15 for 4 years, the growth rate became rapid and stable comparing to shock, burns and cardiopulmonary resuscitation funded projects' number. "Emergency and intensive care medicine/trauma/burns" research fields related to heart, lung, bone/cartilage/muscle, stomach/intestinal/liver, brain/spinal cord/peripheral nerve and other tissues/organs. The number of funded projects in plastic surgery related research fields in angioma and flap related projects were down below to 3 projects, but the number of funded project in wounds, scar repair related research field were more than other fields relatively. (4) In frontier and research hot issue, the funded rate represent as 23.8%, 21.4%, 19.0% and 23.9% in stem cell related research fields in 4 years respectively. The funded rate average to 20.9% in epigenetic related research fields for four years, the funded rate achieved to break through "zero" in autophagy related research fields, the total rate raised to 32.6% from 2011 to 2013. CONCLUSIONS: The funded number and funding were raised rapidly in the fields of emergency and intensive care medicine/trauma/burns/plastic surgery from NSFC. The application for each proposal should be focus on concise or upgrade the scientific issues to improve the quality. The depth or systematic in content and interdisciplinary research fields (e.g. immunology) should be paid attention to. Sepsis, trauma and burns will be the main stream direction in future in the fields of emergency and intensive care medicine/trauma/burns/plastic surgery. The fields of wound healing and scar, surface organ defects, damage, repair and regeneration, surface tissue/organ transplantation and reconstruction, craniofacial deformities and correction are important develop directions in future work.

Clinical and pathological analysis of the kidney in patients with hypertensive nephropathy.

The aim of the present study was to identify the association between pathological types of kidney and clinical manifestations in patients with hypertensive nephropathy. The blood pressure, fundus, urinalysis test results and renal function changes were analysed in patients who were treated for hypertensive nephropathy. Downward kidney puncture biopsy was performed using a 16G ejection needle with the aid of B ultrasound in 47 cases. The specimens were observed using light microscopy and immunofluorescence. The pathological changes observed in the patients exhibiting symptoms of hypertensive nephropathy varied. The majority of clinical manifestations were benign arteriolar nephrosclerosis, hyaline degeneration of the renal artery and the appearance of a thickened wall of a thickened renal artery wall. Severe cases showed malignant arteriolar nephrosclerosis characterised by fibrinoid necrosis of renal arterioles and intimal hyperplasia. In addition, in the severe cases, fibrinoid necrosis of the afferent arteriole and arcuate artery wall was observed, with severe interlobular artery and arcuate artery myointimal thickening. Renal biopsy in patients with hypertensive nephropathy is safe and feasible. The prognosis and treatment of pathological and clinical disease related to renal pathology is necessary.