A single atom cobalt anchored MXene bifunctional platform for rapid, label-free and high-throughput biomarker analysis and tissue imaging.

Few of single-atom materials have been served as platform to analyze small molecules for surface assisted laser desorption/ionization mass spectrometry (SALDI-MS). Herein, a novel single Co atom-anchored MXene (Co-N-Ti3C2) is prepared to achieve enhanced SALDI-MS and mass spectrometry imaging (MSI) performance for the first time. The Co-N-Ti3C2 films were prepared by a simple in situ self-assembly strategy to generate an efficient SALDI-MS platform. Compared to typical inorganic/organic matrices, Co-N-Ti3C2 films exhibit superior performance in small molecules detection with ultra-high sensitivity (LOD at amol level), excellent repeatability (CV <4%), clean background and wide analyte coverage, enabling accurate quantitative analysis of various low-concentration metabolites from 1 µL biofluid in seconds. Its usage efficiently enhanced SALDI-MS detection of various small-molecule biomarkers such as amino acids, succinic acid, itaconic acid, arachidonic acid, citrulline, prostaglandin E2, creatinine, uric acid, glutamine, D-mannose, cholesterol and inositol in positive ion mode. The blood glucose level in humans was successfully determined from a linearity concentration range (0.25-10 mM). Notably, the Co-N-Ti3C2 assisted SALDI-MSI enables study the spatial distribution of small molecules covering the range central to metabolomics at a high resolution on a tissue section. Furthermore, Co-N-Ti3C2 platform revealed a specific peak profile that distinguishes osteoarthritis (OA) from rheumatoid arthritis (RA) tissue. Density functional theory theoretical investigation revealed that single Co atoms anchored on Ti3C2 could highly enhanced the ionization ability of metabolites, resulting in high-sensitivity and heterogeneous metabolome coverage.

Can radiologic parameters used to detect cervical spinal instability be used in patients with ankylosing spondylitis?

INTRODUCTION: Cervical spinal instability can be difficult to detect in the shock room setting even with the utilization of computed tomography (CT) scans. This may be especially true in patients with cervical degenerative disease, such as ankylosing spondylitis (AS). The purpose of this study was to investigate the influence AS has on various radiologic parameters used to detect traumatic and degenerative instability of the cervical spine, to assess if CT imaging in the shock room is diagnostically appropriate in this patient population. METHODS: A matched, case-control retrospective analysis of patients with AS and controls without AS admitted at two level-1 trauma centers was performed. All patients were admitted via shock room and received a polytrauma CT. Twenty-four CT parameters of atlanto-occipital dislocation/instability, traumatic and degenerative spondylolisthesis, basilar invagination, and prevertebral soft tissue swelling were assessed. Since the study was assessing normal values, study patients were included if they had no injury to the cervical spine. Study patients were matched by age and sex. RESULTS: A total of 78 patients were included (AS group, n = 39; control group, n = 39). The evaluated cervical radiologic parameters were largely within normal limits and showed no significant clinical or morphologic differences between the two groups. CONCLUSION: In this analysis, CT measurements pertaining to various cervical pathologies were not different between patients with and without AS. Parameters to assess for atlanto-occipital dislocation/instability, spondylolisthesis, or basilar invagination in the trauma setting may reliably be used in patients with AS.

Analysis of Factors Affecting Early Functional Recovery of Bernese Periacetabular Osteotomy.

OBJECTIVES: To explore factors affecting the efficacy of Bernese periacetabular osteotomy for the treatment of hip dysplasia. METHODS: A retrospective study was conducted on 44 patients with hip dysplasia who underwent Bernese periacetabular osteotomy with a modified Smith-Peterson approach between January 2017 and November 2019. Among them, 40 were women and four were men. The average age was 31.2 ± 9.4. Preoperative and postoperative imaging parameters were measured. The acetabular top tilt angle, lateral central edge angle, acetabular abduction angle, femoral head extrusion index, sphericity index of femoral head, Shenton line, Tonnis grade of osteoarthritis, joint congruency, p/a ratio, acetabular anteversion angle, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scale scores, and modified Harris hip score (MHHS) were observed. MHHS were divided into three clinically relevant categories: poor (<70 points), good (70-85 points), and excellent (86-91 points). Patient demographic data, as well as preoperative and postoperative radiographic parameters, were subjected to univariate logistic regression analysis. Multiple regression analysis was used to determine factors influencing postoperative MHHS. RESULTS: The follow-up time was 1.0-3.9 years after surgery, with an average of 1.6 years. By the last follow-up, MHHS increased from 70 points before surgery to 91 points after surgery (P < 0.001), WOMAC pain score decreased from 4 points before surgery to 0 points after surgery (P < 0.001). WOMAC functional score decreased (Preoperative: 18.0 [4.0]; Postoperative: 4.0 [0], P = 0.004). Six patients had sensory disturbance of the lateral femoral cutaneous nerve, four of which recovered completely during follow-up. No other complications related to surgical approach, osteotomy, acetabular displacement, acetabular fixation, and postoperative stage were found. There was no significant vascular, nerve, or visceral injuries in any of the patients. On multiple regression analysis, the probability of the postoperative modified Harris hip score of a hip joint with a preoperative lateral center edge angle ≥4.5° being classified as excellent was six times that of angles <4.5° (Exp[ß]: 6.249, 95% CI: 1.03-37.85, P = 0.046). Regression analysis of other factors found no significant correlation with postoperative functional scores. CONCLUSION: Overall functional scores post-PAO significantly improved, and pain symptoms were significantly reduced. Patients with a preoperative lateral center edge angle ≥4.5° had better joint function after surgery.

Additive Effects of VDBP and 1,25(OH)2D3 on the Viability and Apoptosis of Rheumatoid Arthritis Synovial Fibroblasts.

Aim: This study is to investigate the additive effect of Vitamin D-binding protein (VDBP) and 1,25(OH)2D3 on the viability and apoptosis of synovial cells from patients with rheumatoid arthritis (RA). Methods: Synovial tissues and synovial fluid of patients with RA and osteoarthritis (OA) were collected. The expression of VDBP was analyzed with immunohistochemistry and ELISA. CCK-8 assay was applied to detect cell viability. Flow cytometry was used to analyze cell cycle and apoptosis. Results: Immunohistochemical results showed that the expression of VDBP in the synovium of RA patients was significantly lower than that of OA (P<0.05). Similarly, ELISA results presented a lower expression of VDBP in the synovial fluid of RA patients. The results of CCK-8 assay showed that both 1,25(OH)2D3 and VDBP significantly inhibited the viability of rheumatoid arthritis synovial fibroblasts (RASF) (P<0.05). The treatment with 1,25(OH)2D3+VDBP led to more significantly inhibited viability of RASF, compared with 1,25(OH)2D3 alone (P<0.05). The results of flow cytometry showed that 1,25(OH)2D3 and VDBP both promoted the apoptosis of RASF (P<0.05) and 1,25(OH)2D3+VDBP led to a higher proportion of RASF apoptosis, compared with 1,25(OH)2D3 alone (P<0.05). However, 1,25(OH)2D3 and VDBP had no significant effect on the cell cycle of RASF. Additionally, 1,25(OH)2D3 promoted the expression of VDBP in RASF, but not concentration-dependently. Conclusion: VDBP is reduced in the synovial tissue and synovial fluid of RA patients and can inhibit viability of RASF and promote the apoptosis of RASF. The 1,25(OH)2D3 can upregulate the expression of VDBP in RASF. Additionally, VDBP can enhance the effects of 1,25(OH)2D3 on viability and apoptosis of RASF.

IgM+CD27+ B cells possessed regulatory function and represented the main source of B cell-derived IL-10 in the synovial fluid of osteoarthritis patients.

Synovial inflammation is observed in patients with osteoathritis (OA) and likely contributed to its exacerbation. Regulatory B (Breg) cells are shown to suppress inflammation in various diseases, including rheumatoid arthritis (RA). To examine whether Breg cells also participated in OA, we examined the synovial fluid from OA patients, and compared with that in RA patients. In OA synovial fluid, IL-10-producing B cells were present directly ex vivo and were increased upon stimulation, indicating that B cells were a source of IL-10 directly at the affected site of OA patients. Interestingly, the frequency of IL-10+ cells in synovial B cells was higher in OA patients than in RA patients, but the total number of IL-10+ B cells in OA was lower than that in RA, suggesting that OA patients presented lower B cell infiltration than RA patients. Phenotypical analysis demonstrated that the IL-10+ B cells were IgM+ and CD27+, but not CD24hi or CD38hi. To allow functional analysis of IgM+CD27+ B cells, the IgM+CD27+ B cells in the blood of OA patients were examined. These blood IgM+CD27+ B cells expressed more IL-10, but less CD80 and CD86 than non-IgM+CD27+ B cells. Blood IgM+CD27+ B cells suppressed the proliferation and IFN-γ expression of autologous T cells, and this effect could be reverted if IL-10 was inhibited. Furthermore, we found that patients with more severe OA presented lower levels of IL-10+ B cells in the synovial fluid. Together, our study described an IgM+CD27+ B cell subset in OA patients, which represented the major IL-10-secreting B cell type in the synovial fluid of OA patients and possessed regulatory function.

1,25-Dihydroxyvitamin D3 attenuates disease severity and induces synoviocyte apoptosis in a concentration-dependent manner in rats with adjuvant-induced arthritis by inactivating the NF-κB signaling pathway.

An aggressive proliferation of synoviocytes is the hallmark of rheumatoid arthritis (RA). Emerging evidence shows that inhibiting the NF-κB signaling pathway with 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] may be a therapeutic approach for controlling inflammatory diseases. In this study, we demonstrated the protective effects of three different 1,25(OH)2D3 concentration on adjuvant-induced arthritis (AA) rats through the NF-κB signaling pathway and their pro-apoptotic roles in cultured adjuvant-induced arthritis synoviocytes (AIASs). AA rats were prepared by injecting complete Freund's adjuvant and independently given daily intraperitoneal injection of 1,25(OH)2D3 at concentrations of 50, 100, and 300 ng/day/kg. Subsequently, AIASs were isolated from the inflamed joints of AA rats to test the effects of 1,25(OH)2D3 on AIASs in vitro. Intraperitoneal injection of 1,25-(OH)2D3 was found to induce a concentration- and time-dependent improvement in relieving the symptoms of AA. We found an increased paw withdrawal thermal latency (PWTL) in the affected paw of AA rats as the concentration of 1,25-(OH)2D3 increased. 1,25-(OH)2D3 treatment reduced levels of inflammatory factors in synovial tissues of AA rats. In the case of cultured AIASs, 1,25-(OH)2D3 was shown to inhibit cell proliferation and induce cell apoptosis in a concentration-dependent manner. Additionally, 1,25-(OH)2D3 inhibited the activation of the NF-κB signaling pathway. In conclusion, our study provides evidence emphasizing that 1,25(OH)2D3 has the potential to attenuate disease severity in RA potentially due to its contributory role in synoviocyte proliferation and apoptosis. The protective role of 1,25(OH)2D3 against RA depends on the NF-κB signaling pathway.

Analysis of skeletal muscle microcirculation in a porcine polytrauma model with haemorrhagic shock.

Polytraumatised patients with haemorrhagic shock are prone to develop systemic complications, such as SIRS (systemic inflammatory response syndrome), ARDS (acute respiratory distress syndrome) and MOF (multiple organ failure). The pathomechanism of severe complications following trauma is multifactorial, and it is believed that microcirculatory dysfunction plays an important role. The aim of this study was to determine the changes in the microcirculation in musculature over time during shock and subsequent resuscitation in a porcine model of haemorrhagic shock and polytrauma. Twelve pigs (German Landrace) underwent femur fracture, liver laceration, blunt chest trauma, and haemorrhagic shock under standard anaesthesia and intensive care monitoring. Microcirculation data were measured from the vastus lateralis muscle using a combined white light spectrometry and laser spectroscopy system every 15 min during the shock and resuscitation period, and at 24, 48, and 72 h. Oxygen delivery and oxygen consumption were calculated and compared to baseline. The relative haemoglobin, local oxygen consumption, and saturation values in the microcirculation were observed significantly lower during shock, however, no changes in the microcirculatory blood flow and microcirculatory oxygen delivery were observed. After resuscitation, the microcirculatory blood flow and relative haemoglobin increased and remained elevated during the whole observation period (72 h). In this study, we observed changes in microcirculation during the trauma and shock phases. Furthermore, we also measured persistent dysfunction of the microcirculation over the observation period of 3 days after resuscitation and haemorrhagic shock. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:1377-1382, 2018.

Using IL-6 concentrations in the first 24 h following trauma to predict immunological complications and mortality in trauma patients: a meta-analysis.

PURPOSE: In previous studies, interleukin-6 (IL-6) has been shown to have a high predictive value for the development of complications and mortality after trauma; however, there is some uncertainty around these results. The aim of this meta-analysis was to assess the value of early IL-6 levels (within the first 24 h after trauma) for predicting post-traumatic complications [acute respiratory distress syndrome (ARDS), systemic inflammatory response syndrome (SIRS), sepsis, multiple organ failure (MOF), and multiple organ dysfunction syndrome (MODS)] and mortality. METHODS: A systemic literature review (from January 01, 1990, to June 03, 2017) of English-language articles was carried out using Pubmed, the Cochrane Central Register of Controlled Trials, Embase, and Web of Science. The search terms used were IL-6 (IL6, IL-6, interleukin 6, or interleukin-6); trauma (trauma*, polytrauma*, multitrauma*, injury, or injury severity score); complications (complication*, ARDS, SIRS, sepsis, MOF, or MODS); and mortality (survival, death). Eleven publications (775 patients) out of 1812 fulfilled the criteria. Fixed-effective models were used for data analysis. Statistical heterogeneity was estimated by a Chi-squared Q test and I 2 statistics, and publication bias was assessed with Egger's test. RESULTS: Results showed that the concentrations of IL-6 within the first 24 h after trauma were significantly higher in the group of patients who had complications or who died [standardized mean difference (SMD) = 0.399; 95% confidence interval (CI) 0.217, 0.580; I 2 = 0.0%; P(heterogeneity) = 0.489]. Subgroup results showed a significant correlation for mortality [SMD = 0.610; 95% CI 0.322, 0.898; I 2 = 0.0%; P(heterogeneity) = 0.708] and MOF/MODS [SMD = 0.334; 95% CI 0.028, 0.639; I 2 = 0.0%; P(heterogeneity) = 0.512] with IL-6, but not for sepsis [SMD = 0.194; 95% CI - 0.095, 0.484; I 2 = 0.0%; P(heterogeneity) = 0.512]. Significance was also found in both ISS ≥ 9 [SMD = 0.461, 95% CI 0.131, 0.791, I 2 = 5.6%, P(heterogeneity) = 0.365] and ISS ≥ 16 [SMD = 0.372, 95% CI 0.155, 0.588, I 2 = 1.5%, P(heterogeneity) = 0.413]. CONCLUSION: In conclusion, this meta-analysis showed that serum concentration of IL-6 within the first 24 h after trauma could be useful for the prediction of post-traumatic complications, particularly MOF/MODS and mortality.

Dose-dependent effects of peroxisome proliferator-activated receptors ß/δ agonist on systemic inflammation after haemorrhagic shock.

INTRODUCTION: PPARß/δ agonists are known to modulate the systemic inflammatory response after sepsis. In this study, inflammation modulation effects of PPARß/δ are investigated using the selective PPARß/δ agonist (GW0742) in a model of haemorrhagic shock (HS)-induced sterile systemic inflammation. METHODS: Blood pressure-controlled (35±5mmHg) HS was performed in C57/BL6 mice for 90min. Low-dose GW0742 (0.03mg/kg/BW) and high-dose GW0742 (0.3mg/kg/BW) were then administered at the beginning of resuscitation. Mice were sacrificed 6h after induction of HS. Plasma levels of IL-6, IL-1ß, IL-10, TNFα, KC, MCP-1, and GM-CSF were determined by ELISA. Myeloperoxidase (MPO) activity in pulmonary and liver tissues was analysed with standardised MPO kits. RESULTS: In mice treated with high-dose GW0742, plasma levels of IL-6, IL-1ß, and MCP-1 were significantly increased compared to the control group mice. When compared to mice treated with low-dose GW0742 plasma levels of IL-6, IL-1ß, GM-CSF, KC, and MCP-1 were significantly elevated in high-dose-treated mice. Low-dose GW0742 treatment was associated with a non-significant downtrend of inflammatory factors in mice with HS. No significant changes of MPO activity in lung and liver were observed between the control group and the GW0742 treatment groups. CONCLUSION: This study identified dose-dependent effects of GW0742 on systemic inflammation after HS. While high-dose GW0742 substantially enhanced the systemic inflammatory response, low-dose GW0742 led to a downtrend of pro-inflammation cytokine expression. The exact mechanisms are yet unknown and need to be assessed in further studies.

Outcomes of surgery for acromioclavicular joint dislocation using different angled hook plates: a prospective study.

PURPOSE: Hook plate fixation is widely used to treat acromioclavicular joint dislocation. However, there are many post-operative complications affecting the effect of treatment. The aim of this study is to evaluate the efficacy of the clavicular hook plate with different hook angles as a method of treatment in AC joint dislocation, and to guide the clinical application of hook plate. METHODS: We prospectively analysed 54 patients who were diagnosed with AC joint dislocation and treated with hook plate fixation by different hook angles. The patients were randomised into three groups: the -20° < AHP < 0° group, the 20° > AHP > 0° group and the 40° > AHP > 20° group. All patients were required to conform to regular follow-up post-operatively. Routine imaging to the shoulder was obtained to evaluate maintenance of the dislocation and the implant. Constant-Murley criteria were used to evaluate functional results. RESULTS: There were 19 patients in the -20° < AHP < 0° group, with one lost to follow-up, 22 patients in the 20° > AHP > 0° group, with two male patients lost to follow-up, and one female patient excluded because of no follow-up consent, and 19 patients in the 40° > AHP > 20° group, with one female and one male patient lost to follow-up. The Constant score was 61.8 ± 12.8, 74.7 ± 9.2 and 70.7 ± 9.4 before implant removal, and 78.8 ± 8.3, 87.1 ± 6.4 and 85.0 ± 6.1 after implant removal in the -20° < AHP < 0°, 20° > AHP > 0° and 40° > AHP > 20° groups, respectively. The functional results of the 20° > AHP > 0° and 40° > AHP > 20° groups were significantly better than the -20° < AHP < 0° group (P < 0.05), but the functional results of the 20° > AHP > 0° and 40° > AHP > 20° groups were not statistically significant. The CCD was 98.1 ± 4.8%, 107.5 ± 5.1% and 105.5 ± 4.1% before implant removal, and 98.8 ± 4.6%, 108.3 ± 4.8% and 107.2 ± 3.3% after implant removal in the three groups, respectively. The CCD of the 20° > AHP > 0° and 40° > AHP > 20° groups were statistically significantly different from the -20° < AHP < 0° group (P < 0.001). However, there was no statistical difference between the 20° > AHP > 0° group and the 40° > AHP > 20° group. Post-operative persistent pain occurred in 18.5% of all patients, post-operative stiffness occurred in 25.9% of all patients and 24.0% of patients had subacromial erosion. CONCLUSIONS: Hook plate treatment for AC joint dislocation can achieve the desired results, but the efficacy was significantly different depending on the different angles of the hook plate. AHP should be controlled within the range of 0-40° as much as possible when making clinical decisions.

The low binding affinity of ADAMTS4 for citrullinated fibronectin may contribute to the destruction of joint cartilage in rheumatoid arthritis.

OBJECTIVES: Rapid cartilage degradation in the joints is observed in rheumatoid arthritis (RA). ADAMTS4 (a disintegrin and metalloproteinase with thrombospondin motifs-4) degrades aggrecan, the primary component of cartilage, therefore contributing to joint erosion in RA. The proteolytic activity of ADAMTS4 is inhibited by fibronectin (FN). FN is abundantly expressed in the synovia in RA and is modified by citrullination, the conversion of peptidylarginine to citrulline. This study aims to investigate the binding ability of citrullinated FN (cFN) to ADAMTS4 and the effect of cFN on aggrecanase activity. METHODS: The full-length recombinant ADAMTS4 was purified from HEK293 cells that were transiently transfected with a full-length cDNA coding for human ADAMTS4. A 40-kDa FN fragment exhibiting heparin binding was citrullinised with rabbit peptidylarginine deaminase. The binding activity of the full-length recombinant ADAMTS4 to cFN was investigated in an in vitro binding assay. The proteolytic activity of ADAMTS4 after incubation with cFN was determined using an aggrecanase activity kit, in which the ARGSVIL peptide is produced by digestion with aggrecanase. RESULTS: cFN displayed significantly decreased binding activity with ADAMTS4 compared with FN. The full-length ADAMTS4 produced large amounts of the ARGSVIL peptide, but the amount was markedly decreased in the presence of FN. The production of this peptide approached the normal level when the full-length ADAMTS4 was incubated with cFN. CONCLUSIONS: FN following citrullination is less effective in inhibiting the proteolytic activity of ADAMTS4. It is known that PADI4, an enzyme active in citrullination, is highly expressed in the synovial tissue in RA. Our results suggest that PADI4 in the RA synovium may contribute to cartilage destruction via the citrullination of FN.