Safety of Janus kinase inhibitors compared to biological DMARDs in patients with rheumatoid arthritis and renal impairment: the ANSWER cohort study

Data on the safety of Janus kinase inhibitors (JAKis) in patients with renal impairment are lacking. This study aimed to investigate the safety of JAKis compared to biological (b) DMARDs in patients with rheumatoid arthritis (RA) and renal impairment. We used a multi-centre observational registry of patients with RA in Japan (the ANSWER cohort). We assessed the drug retention rates of b/targeted synthetic DMARDs with different modes of action (tumour necrosis factor inhibitors (TNFis), immunoglobulins fused with cytotoxic T-lymphocyte antigen (CTLA-4-Ig), interleukin-6 receptor inhibitors (IL-6Ris), and JAKis) in patients with RA stratified by pre-treatment estimated glomerular filtration rate (eGFR) levels. The time to discontinuation of bDMARDs or JAKis was analysed using a multivariate Cox proportional hazards model This study included 3775 patients, who were classified into three groups (the normal group (eGFR ≥ 60 mL/min/1.73 m2): 2893 patients; CKDa group (eGFR 45-60 mL/min/1.73 m2): 551; and CKDb group (eGFR < 45 mL/min/1.73 m2): 331). In the CKDb group, the 12-month drug retention rate due to adverse events (AE) was the lowest in patients treated with JAKi (TNFi: 93.1%; IL-6Ri: 94.1%; CTLA-4-Ig: 92.3%; JAKi: 75.1%). In the normal and CKDa groups, drug retention rates due to AE were similar among patients treated with bDMARDs and JAKi. In contrast, drug retention rates due to inefficacy were similar between bDMARDs and JAKis in all groups. In the Cox-proportional model, in the CKDb group, TNFi, IL-6Ri, and CTLA-4-Ig showed lower incidence of drug discontinuation due to AE than JAKis (TNFi: hazard ratio = 0.23 (95% confidence interval 0.09-0.61), IL-6Ri: 0.34 (0.14-0.81), CTLA-4-Ig: 0.36 (0.15-0.89)). JAKis showed the lowest drug retention due to AE in patients with moderate-to-severe and severe renal impairment (eGFR < 45 mL/min/1.73 m2). Physicians should pay more attention to renal function when using JAKis than when using bDMARDs.

Association of large joint involvement at the start of biological disease-modifying antirheumatic drugs and Janus kinase inhibitors with disease activity and drug retention in patients with rheumatoid arthritis: The ANSWER cohort study

AIM

To investigate the association of large joint involvement (LJI) with disease activity and drug retention in patients with rheumatoid arthritis (RA) who started receiving a biological disease-modifying antirheumatic drug or Janus kinase inhibitor.

METHODS

Patients with RA from a Japanese multicenter observational registry were enrolled. Our definition of large joints included the shoulder, elbow, hip, knee, and ankle joints. Linear mixed-effects models were used to examine changes in the clinical disease activity index (CDAI) score at Week 24 as the primary outcome, and drug retention rates were compared between patients with and without LJI using Cox proportional hazards models. We examined the potential effect modifications of changes in the CDAI by baseline characteristics.

RESULTS

Overall, 2507 treatment courses from 1721 patients were included (LJI, 1744; no LJI, 763). Although LJI was associated with significantly higher changes in CDAI from baseline at Week 24 (difference in change in CDAI: -5.84 [-6.65 to -5.03], p < .001), CDAI was significantly higher in patients with LJI over time. Retention rates were similar in both groups. The association of LJI with changes in disease activity was more prominent in patients with a short disease duration, negative anti-citrullinated peptide antibodies, and interleukin-6 receptor inhibitor (IL-6Ri) use.

CONCLUSION

Although LJI was associated with a greater reduction in disease activity from baseline, higher disease activity at baseline was not offset over time in patients with LJI, demonstrating that LJI is an unfavorable predictor. An early treat-to-target strategy using an IL-6Ri may be beneficial for patients with LJI.

LIGHT regulated gene expression in rheumatoid synovial fibroblasts

BACKGROUND

Synovial hyperplasia caused by rheumatoid arthritis (RA), an autoimmune inflammatory disease, leads to the destruction of the articular cartilage and bone. A member of the tumor necrosis factor superfamily, Lymphotoxin-related inducible ligand that competes for glycoprotein D binding to herpes virus entry mediator on T cells (LIGHT) has been shown to correlate with the pathogenesis of RA.

METHODS

We used cDNA microarray analysis to compare the expression of genes in rheumatoid fibroblast-like synoviocytes with and without LIGHT stimulation.

RESULTS

Significant changes in gene expression (P-values < 0.05 and fold change ≥ 2.0) were associated mainly with biological function categories of glycoprotein, glycosylation site as N-linked, plasma membrane part, integral to plasma membrane, intrinsic to plasma membrane, signal, plasma membrane, signal peptide, alternative splicing, and topological domain as extracellular.

CONCLUSIONS

Our results indicate that LIGHT may regulate the expression in RA-FLS of genes which are important in the differentiation of several cell types and in cellular functions.

Sperm replacement in sperm-storage tubules causes last-male sperm precedence in chickens

1. This study elucidated the last-male sperm precedence (LMSP) mechanism in chickens by examining replacement in storage tubules (SSTs) after multiple artificial inseminations (AI) and the effects of seminal plasma (SP) and male breed on sperm replacement in SSTs.2. Hens were artificially inseminated with fluorescent dye-labelled spermatozoa from White Leghorn (WL) chickens. Secondary AI was conducted 3 d later with sperm labelled with different nuclear fluorescent dye. Percentage of first and second inseminated sperm in SSTs and their logarithmic odds were calculated. The effect of SP on LMSP was examined using (1) Lake's solution-washed sperm before second insemination, and (2) SP injected continuously after first insemination. Effect of breed difference on sperm replacement was investigated using Barred Plymouth Rock (BP) sperm.3. Successive WL-sperm inseminations at three-day intervals caused > 70% stored sperm replacement in SSTs. Although SP removal from sperm from second insemination significantly decreased replacement, its intra-vaginal injection did not affect release. Secondary insemination using BP sperm significantly increased replacement.4. Sperm replacement is a major factor favouring LMSP in domestic chickens. Two fluorescent staining of sperm, and intra-vaginal multiple AI technique have enabled visualisation, differentiation, and quantification of multiple inseminated sperm stored in the SSTs.

The severity of preoperative varus deformity affects the feasibility of correcting lower limb alignment with medial unicompartmental knee arthroplasty

BACKGROUND

The relationship between the severity of preoperative varus deformity and the amount of its correction in unicompartmental knee arthroplasty (UKA) as well as the thickness of the insert has not been well known.

METHODS

One hundred and three patients who underwent medial fixed-bearing UKA with the use of the spacer block method were assessed. After the component gap in extension was measured using a UKA tensor, the pre-osteotomy gap was calculated from the thickness of the bone cuts. The relationship between the preoperative hip-knee-ankle (HKA) angle as well as the pre-osteotomy gap and the amount of change in HKA angle were analysed. Also, preoperative HKA angle and the thickness of the bone cuts were compared among groups by the insert thickness.

RESULTS

The mean preoperative HKA angle was 7.7 ± 3.1° varus. Patients with more varus deformity and those with a wider pre-osteotomy gap showed a more valgus change in HKA angle. As for the thickness of the insert, the preoperative HKA angle of the patients with the thinnest insert was significantly smaller (less varus) than that of those with the thicker insert while no statistically significant difference was found among the insert groups regarding the amount of the bone cuts.

CONCLUSIONS

The severity of the preoperative varus deformity as well as the intraoperative pre-osteotomy gap related to the amount of change in HKA angle. As thick inserts tended to be used in severe varus knees, the tibial bone cut can be reduced in such cases.

Krüppel-like factor 15 deficiency exacerbates osteoarthritis through reduced expression of peroxisome proliferator-activated receptor gamma signaling in mice

OBJECTIVE

Krüppel-like zinc finger transcription factors (KLFs) play diverse roles in mammalian cell differentiation and development. In this study, we investigated the function of KLF15 in the progression of osteoarthritis (OA).

METHODS

0Destabilization of the medial meniscus (DMM) surgery was performed in 10-week-old male wild-type control (WT) mice and cartilage-specific KLF15 knockout (KO) mice. Histological analysis, immunohistochemistry, and terminal deoxynucleotidyl transferase deoxyuridine triphosphate nick-end labeling staining were performed. Morphological changes were measured using microcomputed tomography. Six mice from each group were analyzed (total number of mice analyzed: 60). In vitro, immunofluorescence, quantitative reverse transcription-polymerase chain reaction, and western blot analyses were performed.

RESULTS

KLF15 KO DMM mice exhibited significant cartilage degradation compared to WT mice. According to the Osteoarthritis Research Society International cartilage OA-histopathology scoring system, the mean sum score in KLF15 KO mice was significantly higher than that in WT mice at 8 weeks after surgery. Immunohistochemistry results revealed KLF15 KO mice exhibited reduced peroxisome proliferator-activated receptor gamma (PPARγ) expression, increased pIKKα/β, a disintegrin-like and metalloproteinase with thrombospondin motifs (ADAMTS) 5, and Matrix metalloproteinases (MMP13) expression, and reduced Forkhead box O (FOXO1) and Light chain 3B (LC3B) expression. Inhibition of PPARγ phosphorylation accelerated the effects of interleukin (IL) 1β-treatment in both KLF15 KO and WT chondrocytes, and activation of PPARγ expression canceled the IL1β-induced catabolic effects.

CONCLUSION

Our results indicated that the OA phenotype of KLF15 KO DMM mice was influenced by reduced PPARγ expression, including enhanced pIKKα/β, ADAMTS5, and MMP13 expression, reduced autophagy, and increased apoptosis. KLF15 regulation may constitute a possible therapeutic strategy for the treating OA.

Accuracy comparison of cup positioning during total hip arthroplasty using Hip Align and AR-Hip in the supine position

INTRODUCTION

The aim of this study is to compare the accuracy of acetabular cup positioning between the accelerometer-based navigation system and the augmented reality-based navigation system during THA in the supine position.

MATERIALS AND METHODS

This retrospective study included 66 patients (70 hips) who underwent THA using two types of portable navigation system, Hip Align or AR-Hip, in the spine position. The absolute difference between the intraoperative navigation record and postoperative measurement using computed tomography data was evaluated. Preoperative clinical factors that decreased the accuracy of cup positioning by ≥ 3° were analyzed via multiple logistic regression analyses.

RESULTS

The average absolute error of inclination was 2.8 ± 2.6° in Hip Align and 2.7 ± 1.8° in AR-Hip, and absolute anteversion error was 2.5 ± 2.0° in Hip Align and 2.6 ± 2.2° in AR-Hip, and there was no significantly different between the two navigation systems. There was a significant association between the absolute measurement error (≥ 3°) of cup inclination and patients' BMI in the Hip Align group [odds ratio (OR) 1.350; 95% confidence interval (CI) 1.035-1.760; p = 0.027], but not in the AR-Hip group.

CONCLUSIONS

The accuracy of the acetabular cup positioning between the Hip Align and AR-Hip showed no difference during THA in the spine position. The high BMI could have negative influence on the accuracy of cup positioning in THA using Hip Align, thus AR-Hip could be designable for obesity patients.

Real-world comparative study of the efficacy of Janus kinase inhibitors in patients with rheumatoid arthritis: the ANSWER cohort study

OBJECTIVE

This multicentre, retrospective study compared the efficacy and safety of tofacitinib, baricitinib, peficitinib and upadacitinib in real-world clinical settings after minimizing selection bias and adjusting the confounding patient characteristics.

METHOD

The 622 patients were selected from the ANSWER cohort database and treated with tofacitinib (TOF), baricitinib (BAR), peficitinib (PEF) or upadacitinib (UPA). The patient's background was matched using propensity score-based inverse probability of treatment weighting (IPTW) among four treatment groups. The values of Clinical Disease Activity Index (CDAI), C-reactive protein (CRP), and modified Health Assessment Questionnaire (mHAQ) after drug initiation and the remission or low disease activity (LDA) rates of CDAI at 6 months after drug initiation were compared among the four groups. Further, the predictive factor for TOF and BAR efficacy was analysed.

RESULTS

The retention and discontinuation rates until 6 months after drug initiations were not significantly different among the four JAK inhibitors treatment groups. Mean CDAI value, CDAI remission rate, and CDAI-LDA rate at 6 months after drug initiation were not significantly different among treatment groups. Baseline CDAI (TOFA: OR 1.09, P < 0.001; BARI: OR 1.07, P < 0.001), baseline CRP (TOFA: OR 1.32, P = 0.049), baseline glucocorticoid dose (BARI: OR 1.18, 95% CI 1.01-1.38, P = 0.035), a number of previous biological or targeted synthetic disease-modifying antirheumatic drugs (biological/targeted synthetic DMARDs) (BARI: OR 1.36, P = 0.004) were predictive factors for resistance to CDAI-LDA achievement to JAK inhibitor treatment.

CONCLUSION

The efficacy and safety of TOF, BAR, PEF and UPA were not significantly different for the treatment of patients with rheumatoid arthritis.

Trends of disease activity in Japanese patients over 75 years with rheumatoid arthritis from 2014 to 2021- the ANSWER cohort study

OBJECTIVES

To investigate if disease activity among elderly RA patients over 75 years has changed over time in the real-world clinical setting.

METHODS

Data from an observational multicentre registry of RA patients in Japan were analyzed. The primary outcome was to evaluate the changes in the proportion of very elderly RA patients (over 75 years) who achieved remission and low disease activity, from 2014 to 2021. The secondary outcome was to identify factors associated with remission and low disease activity by comparing demographic and clinical characteristics among the patients who had a study visit within the study period, using multivariate logistic regression.

RESULTS

A total of 32 161 patient visits were identified from 2014 to 2021. The proportion of patients over 75 years increased from 16.5% to 26.9%, with biologics and targeted-synthetic disease modifying anti-rheumatic drugs (b/tsDMARDs) usage increasing and glucocorticoids usage decreasing, while conventional-synthetic DMARDs usage remained relatively stable. The proportion of RA patients over 75 years achieving remission and low disease activity significantly increased from 62.2% to 78.2% (p for trend < 0.001). A negative factor associated with achieving remission and low disease activity was glucocorticoid usage, seropositivity, and history of previous b/tsDMARDs use while MTX usage was associated positively, independent of other predictors.

CONCLUSIONS

In our cohort, disease activity among very elderly RA patients has improved over time. The study suggests the importance of using a treat-to-target approach in very elderly RA patients to improve clinical outcomes.

Targeting the neutral hip-to-calcaneus axis in kinematically aligned total knee arthroplasty is feasible with fewer alignment outliers for varus osteoarthritic patients

PURPOSE

Assessment of the conventional mechanical axis (MA) (hip-to-talus axis) is reported to result in constitutional varus in the native knee. However, the ground MA (hip-to-calcaneus axis), which is the line from the hip center to the bottom of the calcaneus, passes through the center of the knee joint in the native knee and is a possible alternative target for total knee arthroplasty (TKA) assessments. Therefore, this study aimed to present a "ground kinematically aligned (KA)-TKA." In this technique, the femoral component is placed on the cylindrical axis using the calipered technique and the tibial component is placed to give a neutral ground MA. Radiographical investigation was used to determine whether physiological alignment can be individually achieved with ground KA-TKA; this was compared with that of a tibia-restricted modified KA-TKA, referring to conventional MA (hip-to-talus axis) results.

METHODS

As the primary endpoint, this prospective cohort study compared the ground MA ratios of the knee joints in 40 ground KA-TKAs (G group: Coronal Plain Alignment of the Knee (CPAK) 28 type I, 7 II, 1 IV, and 4 V) with those of the preceding 60 modified KA-TKAs (M group: CPAK 46 type I, 12 II, and 2 V) performed for patients with varus osteoarthritis (OA). The number of outliers differing over ± 5% from the neutral were compared between groups using the χ2-test. The Hip-knee-ankle (HKA) angle, coronal femoral/tibial component alignment (FCA/TCA), and joint line orientation angle (JLOA) were compared between the groups using non-paired t-tests. Statistical significance was set at p < 0.05.

RESULTS

The G group had a higher ratio of the ground MA passing through the knee center than the M group did; outliers differing over ± 5% from the neutral of the ground MA were 2/40 cases in the G group and 20/60 cases in the M group, which was a significant difference (p = 0.001). The HKA angle, FCA/TCA, and JLOA were not significantly different between the groups.

CONCLUSIONS

Targeting the ground MA in KA-TKA for patients with varus OA was feasible and has the potential to provide a physiological alignment more similar to the native knee in TKA than other kinematic alignment techniques.

LEVEL OF EVIDENCE

Level III.

Whole-genome sequencing analysis of molecular epidemiology and silent transmissions causing meticillin-resistant Staphylococcus aureus bloodstream infections in a university hospital

BACKGROUND

The emergence of novel genomic-type clones, such as community-associated meticillin-resistant Staphylococcus aureus (MRSA) and livestock-associated MRSA, and their invasion into hospitals have become major concerns worldwide; however, little information is available regarding the prevalence of MRSA in Japan. Whole-genome sequencing (WGS) has been conducted to analyse various pathogens worldwide. Therefore, it is important to establish a genome database of clinical MRSA isolates available in Japan.

AIM

A molecular epidemiological analysis of MRSA strains isolated from bloodstream-infected patients in a Japanese university hospital was conducted using WGS and single-nucleotide polymorphism (SNP) analysis. Additionally, through a review of patients' clinical characteristics, the effectiveness of SNP analysis as a tool for detecting silent nosocomial transmission that may be missed by other methods was evaluated in diverse settings and various time points of detection.

METHODS

Polymerase-chain-reaction-based staphylococcal cassette chromosome mec (SCCmec) typing was performed using 135 isolates obtained between 2014 and 2018, and WGS was performed using 88 isolates obtained between 2015 and 2017.

FINDINGS

SCCmec type II strains, prevalent in 2014, became rare in 2018, whereas the prevalence of SCCmec type IV strains increased from 18.75% to 83.87% of the population, and became the dominant clones. Clonal complex (CC) 5 CC8 and CC1 were detected between 2015 and 2017, with CC1 being dominant. In 88 cases, SNP analyses revealed nosocomial transmissions among 20 patients which involved highly homologous strains.

CONCLUSIONS

Routine monitoring of MRSA by whole-genome analysis is effective not only for gaining knowledge regarding molecular epidemiology, but also for detecting silent nosocomial transmission.

Granular flow experiment using artificial gravity generator at International Space Station

Studying the gravity-dependent characteristics of regolith, fine-grained granular media covering extra-terrestrial bodies is essential for the reliable design and analysis of landers and rovers for space exploration. In this study, we propose an experimental approach to examine a granular flow under stable artificial gravity conditions for a long duration generated by a centrifuge at the International Space Station. We also perform a discrete element simulation of the granular flow in both artificial and natural gravity environments. The simulation results verify that the granular flows in artificial and natural gravity are consistent. Further, regression analysis of the experimental results reveals that the mass flow rate of granular flow quantitatively follows a well-known physics-based law with some deviations under low-gravity conditions, implying that the bulk density of the granular media decreases with gravity. This insight also indicates that the bulk density considered in simulation studies of space probes under low-gravity conditions needs to be tuned for their reliable design and analysis.

Prosthetic orientation, limb alignment, and soft tissue balance with bi-cruciate stabilized total knee arthroplasty: a comparison between the handheld robot and conventional techniques

PURPOSE

This study aimed to examine the prosthetic orientations, limb alignment, intraoperative soft tissue balance, and early clinical outcomes associated with the use of the relatively new handheld robot technique compared to those associated with the use of the conventional alignment guide for bi-cruciate stabilized total knee arthroplasty (TKA).

METHODS

This retrospective cohort study compared the prosthetic orientation and limb alignment of 35 patients who underwent TKA using robotic assistance (robot group) with those of patients who underwent TKA using a conventional alignment guide (control group). The coronal femoral component alignment (FCA), coronal tibial component alignment (TCA), and the hip-knee-ankle (HKA) angle were compared between groups. Intraoperative soft tissue balance, including the joint component gap and varus/valgus balance assessed by an offset-type tensor, were also compared between groups. One year postoperatively, the clinical outcomes, including the range of motion and 2011 Knee Society Score (KSS), were compared between groups.

RESULTS

The HKA angle and FCA were 0.1° varus and 0.1° varus, respectively, in the robot group and 1.3° varus and 1.3° varus, respectively, in the control group. The difference in the HKA angle and the FCA, but not the TCA, between groups was statistically significant (p < 0.05). The intraoperative soft tissue balance showed more stable joint component gaps and varus/valgus balances throughout the range of motion in the robot group than in the control group. Clinical outcomes of the robot group showed superior 2011 KSS subscales compared to those of the control group.

CONCLUSION

The accuracy of the implantations and stable soft tissue balance in the robot group were superior to those of the control group. The robot group also had superior patient-reported scores for early clinical outcomes.

Acute Deterioration of Patient with Sudden Onset of Shock Caused by Group G Streptococcus Infection after Revision Total Knee Arthroplasty: A Case Report

BACKGROUND Periprosthetic joint infection is a difficult complication, especially in patients with rheumatoid arthritis. Life-threatening septic shock due to periprosthetic joint infection caused by group G streptococcus is rare, and there have been few reports about its treatment. We describe a successful case of sudden onset septic shock due to group G Streptococcus infection after revision total knee arthroplasty. CASE REPORT A 61-year-old woman with rheumatoid arthritis treated with biological disease-modifying antirheumatic drugs for about 12 years presented with acute right knee pain and shock 6 months after revision total knee arthroplasty. Periprosthetic joint infection caused by group G Streptococcus was diagnosed. She was admitted to the Intensive Care Unit, treated with respiratory support and dialysis, and underwent irrigation, debridement, and polyethylene liner exchange as the first surgery. At 9 days after the first surgery, she underwent the second surgery, consisting of implant removal and antibiotic spacer placement due to failure. It took approximately 7 weeks to normalize the levels of systemic markers of inflammation with intravenous antibiotics and then oral antibiotics for further 12 weeks, but re-revision total knee arthroplasty was successfully performed 1.5 years later. At a 1-year follow-up from the final surgery, she was able to walk with a cane and had no symptoms of infection. CONCLUSIONS In such cases with sudden onset of septic shock due to periprosthetic joint infection, appropriate and prompt surgical treatment should be performed to save the infected limb as well as the patient's life.

Association between habitual hot spring bathing and depression in Japanese older adults: A retrospective study in Beppu

OBJECTIVES

Thermal therapy is used to manage various psychological diseases, such as depression. We investigated the relationship between hot spring bathing and depression in older adults using questionnaire responses.

DESIGN AND SETTING

We comprehensively evaluated the preventive effects of long-term hot spring bathing in 10429 adults aged ≥ 65 years in Beppu, Japan, by conducting a questionnaire study on the prevalence of depression (n = 219).

MAIN OUTCOME MEASURES

Odds ratios (ORs) with 95% confidence intervals (CIs) were calculated using a multivariable logistic regression model for history of depression.

RESULTS

A separate multivariable logistic regression model for inference showed that female sex (OR, 1.56; 95 % CI, 1.17-2.08; p = 0.002), arrhythmia (OR, 1.73; 95 % CI, 1.18-2.52; p = 0.004), hyperlipidemia (OR, 1.63; 95 % CI, 1.14-2.32; p = 0.006), renal disease (OR, 2.26; 95 % CI, 1.36-3.75; p = 0.001), collagen disease (OR, 2.72; 95 % CI, 1.48-5.02; p = 0.001), allergy (OR, 1.97; 95 % CI, 1.27-3.04; p = 0.002), and habitual daily hot spring bathing (OR, 0.63; 95 % CI, 0.41-0.94; p = 0.027) were independently significantly associated with a history of depression.

CONCLUSIONS

We found an inverse relationship between habitual daily hot spring bathing and history of depression. Prospective randomized controlled trials on habitual daily hot spring bathing as a treatment for depression are warranted to investigate whether the use of hot springs can provide relief to those with psychiatric and mental health disorders.

Polyarthritis presented in a patient with untreated chronic hepatitis B infection

Hepatitis B virus (HBV) infection can cause arthritis, but it is rarely reported. In the current report, we present a case of chronic polyarthritis in a patient with untreated HBV infection. A 63-year-old woman suffering from polyarthritis in her fingers visited our institution. She had experienced exacerbations and remissions of polyarthritis for more than 20 years. She had been diagnosed with rheumatoid arthritis and had been treated with conventional synthetic disease-modifying antirheumatic drugs (csDMARDs) and nonsteroidal anti-inflammatory drugs by her primary care doctor, but the csDMARDs were discontinued at the request of the patient 10 years before the first visit to our hospital. The blood test showed negative for rheumatoid factor and anticyclic citrullinated peptides antibody but positive for hepatitis B surface antigen. Hepatitis B surface antigen and HBV-Deoxyribo Nucleic Acid (DNA) were increased to 312.6 (IU/ml) and 4.6 (log copies/ml), respectively. Based on the results of abdominal computed tomography and echography, she was diagnosed with liver cirrhosis. Treatment for HBV infection was begun with oral tenofovir at 25 mg/day. The polyarthritis in her fingers gradually disappeared and has not relapsed for 6 months after the initiation of treatment for HBV infection. When polyarthritis is diagnosed, the possibility that chronic HBV infection can be one of the causes of polyarthritis should be considered.

A combination of acetabular coverage and femoral head-neck measurements can help diagnose femoroacetabular impingement

This study aimed to evaluate the relationship between the radiographical features of combination of the acetabular coverage and the femoral head-neck shape and the occurrence of femoroacetabular impingement (FAI). In this study, 114 patients who had FAI with or without labral tear and mild osteoarthritis were analyzed. Plain radiographs and computed tomography (CT) were taken for evaluation of acetabular coverage and femoral head-neck measurements. The relationship between the combination angle of acetabular coverage and femoral head-neck measurements and the occurrence of FAI was evaluated. The prevalence of FAI patients with the combination angle of CT-anterior CE + α angle ≥100° was 6.1% (7/114 patients). Receiver operator characteristic curve analysis demonstrated a higher area under the curve for combination of CT-anterior center edge angle (ACEA) with the α angle at 0.94 (CT-ACEA +α angle). A threshold for the occurrence of FAI was determined using the combination CT-ACEA + α angle at 100°. The frequency of FAI surgery was significantly higher in patients with a combination angle ≥100° than in those with a smaller angle. The average modified Harris hip score was significantly lower in patients with a combination angle ≥100° than in those with a smaller angle. We suggest that the combination of lateral center edge angle ≥40°, α angle ≥50° and combined angles of CT-ACEA and α angle ≥100° may help diagnosis of FAI. Level of evidence III: retrospective cohort study.

P21 deficiency exhibits delayed endochondral ossification during fracture healing

INTRODUCTION

Endochondral ossification is a complex biological phenomenon involving a variety of factors and cells. Cyclin-dependent kinase inhibitor 1 (p21) inhibits cell cycle progression and is affected by external stress. We recently reported that embryonic endochondral ossification is unaffected by endogenous p21 deficiency. In this study, we evaluated whether p21 expression affects endochondral ossification during fracture healing.

METHODS

Tibial fractures were introduced into p21 knockout (p21^-/-) (n = 24) and wild-type C57BL/6 (p21^+/+) (n = 24) mice at age 10 weeks. Fracture healing was evaluated using radiological, histological, and immunohistochemical (IHC) analyses. The effect of p21 small interfering RNA (siRNA) on ATDC5 cells was assessed in vitro.

RESULTS

The Allen score for fracture healing was lower in p21^-/- mice than in p21^+/+ mice. In addition, p21^-/- mice exhibited larger calluses and lower bone mineral density. IHC analyses showed that p21^-/- mice exhibited delayed endochondral ossification via the Ihh-Runx2-Osterix pathway in vivo. Down-regulation of p21 expression in ATDC5 cells delayed endochondral ossification in vitro.

CONCLUSIONS

p21 deficiency leads to delayed endochondral ossification by attenuating the Ihh-Runx2-Osterix pathway in vivo, and p21 deficiency in hypertrophic chondrocytes causes delayed differentiation of hypertrophic chondrocytes in vitro. p21 plays a role in endochondral ossification during fracture healing.

Rotational mismatch between femoral and tibial components should be avoided in JOURNEY II bi-cruciate stabilized total knee arthroplasty

BACKGROUND

JOURNEY II bi-cruciate stabilized (BCS) knee system, a guided motion total knee arthroplasty (TKA), has been reported to reproduce physiological knee kinematic motion with good clinical outcomes. However, this guided system may be sensitive to the femorotibial rotational alignment.

METHOD

Forty-four patients (50 knees) who underwent JOURNEY II BCS TKA were included in this retrospective study. The 2011 Knee Society Score (KSS) and range of motion were assessed pre-operatively and one year postoperatively. The femoral component rotational angle relative to the surgical epicondylar axis and the tibial component rotational angle relative to Akagi's line were measured postoperatively. The absolute difference between the femoral and tibial component rotational angles was defined as femorotibial component rotational mismatch. The correlation between the parameters of these rotational alignments and postoperative clinical outcomes was evaluated. Additionally, receiver operating characteristic curve analysis was performed to determine the optimal cut-off point of the femorotibial component rotational mismatch.

RESULTS

Mean femoral and tibial component rotational angles were 0.4° (internal rotation) and 0.7° (external rotation), respectively. The rotational mismatch of the femorotibial component was 3.2°. There were negative correlations between femorotibial rotational mismatch and clinical outcomes, including objective knee indicators, patient satisfaction, functional activities, and total 2011 KSS. The area under the curve of the femorotibial component rotational mismatch was 0.768 and the cut-off value identified by the Youden index was 2.8°.

CONCLUSIONS

Excessive rotational mismatch between the femoral and tibial components can negatively influence the clinical outcomes of JOURNEY II BCS TKA.

A genome-wide association study identifying single nucleotide polymorphisms in the PPFIBP2 gene was predictive for interstitial lung disease in rheumatoid arthritis patients

Objective

Genetic polymorphisms might serve as useful prognostic markers for the timely diagnosis of RA. The purpose of this study was to identify genomic factors predictive of the occurrence of interstitial lung disease (ILD) in RA by performing a genome-wide association study of genetic variants, including single nucleotide polymorphisms (SNPs).

Methods

The study population included 306 RA patients. All patients were treated with conventional DMARDs, including 6–16 mg MTX per week. Clinical data and venous blood samples were collected from all patients before administration of DMARDs. A total of 278 347 SNPs were analysed to determine their association with ILD occurrence.

Results

Several SNPs were strongly associated with ILD occurrence (P < 10⁻⁵). rs6578890, which is located on chromosome 11 in the intronic region of the gene encoding tyrosine phosphatase receptor type F polypeptide-interacting protein-binding protein 2 (PPFIBP2), showed the strongest association with ILD occurrence (odds ratio 4.32, P = 10^−7.93).

Conclusion

PPFIBP2 could be a useful genetic marker for occurrence of interstitial pneumonia in RA patients and might help to identify the risk of ILD occurrence before RA treatment, thereby improving patient outcomes.

Comparing the accuracy of three-dimensional mini-optical portable navigation and accelerometer-based portable navigation system for acetabular cup placement during total hip arthroplasty

INTRODUCTION

This study compared the accuracy of three dimensional (3D) mini-optical navigation and accelerometer-based portable navigation systems for cup positioning during a total hip arthroplasty (THA) in the supine position.

MATERIALS AND METHODS

This retrospective cohort study assessed data for 77 hips using 3D mini-optical navigation (n = 37) and accelerometer-based portable navigation (n = 40). The patients underwent THA through the mini-anterolateral approach in the supine position using a portable navigation system. We assessed the preoperative target angles, recorded intraoperative cup angles, postoperative CT imaging angles, cup angle measurement errors, and other clinical parameters.

RESULTS

The mean absolute differences in radiographic inclination were similar between 3D mini-optical navigation and accelerometer-based portable navigation systems during THA in the supine position (2.8° ± 1.7° vs 2.8° ± 1.9°, p = 0.637). The mean absolute differences in radiographic anteversion were also similar (2.6° ± 2.3° vs 2.5° ± 1.9°, p = 0.737). Cup malalignment (absolute difference of inclination or anteversion between postoperative CT and preoperative target angle of > 5°) was significantly associated with body mass index (BMI) in accelerometer-based portable navigation but not in 3D mini-optical navigation.

CONCLUSIONS

This is the first study to compare the accuracy of cup positioning between 3D mini-optical and accelerometer-based navigations in THA in the supine position. Both portable navigation systems accurately identified the orientation of cup placement. The accuracy of 3D mini-optical navigation is not affected by high BMI and may be preferred over other options in such patients.

The Effect of Prosthesis Type on Intraoperative Soft-Tissue Balance and Clinical Outcomes in Modified Kinematically Aligned Cruciate-Retaining Total Knee Arthroplasty

INTRODUCTION

 Kinematically aligned total knee arthroplasty (KA-TKA) has gained interest for achieving more favorable clinical outcomes than mechanically aligned TKA. One of the advantages of KA-TKA is reported to be an easy acquisition of intraoperative soft-tissue balance without excessive medial release for varus osteoarthritis. However, we hypothesized that the prosthesis type affects intraoperative soft-tissue balance even in the KA-TKA. The present study aimed to compare intraoperative soft-tissue balance and clinical outcomes of KA-TKAs using single-radius (SR) or multiradius (MR) prostheses.

MATERIALS

 AND METHODS: Consecutive 70 cruciate-retaining modified KA-TKAs (31 SR and 39 MR) were performed in patients with varus-type osteoarthritis using a navigation system. Intraoperative soft-tissue balance including joint component gap and varus/valgus balance was measured with femoral component placement and patellofemoral joint reduction throughout the range of motion using offset-type tensor and compared between the two groups. Two years postoperatively, the range of motion and 2011 Knee Society Scores were compared between the two groups.

RESULTS AND CONCLUSION

 Joint component gaps showed no significant differences between the two groups from 0 to 30 degrees of flexion. However, during 60 to 120 degrees of flexion, joint component gaps of SR group showed significantly larger values than those of MR group (p < 0.05). There were no significant differences in varus/valgus balance throughout the range of motion between the two groups. The postoperative clinical outcomes showed no significant differences between the two groups.

INTERPRETATION

 Despite no difference in clinical outcomes, joint component gap showed different patterns due to the prosthesis type in modified KA-TKAs.

P-039 Male age is associated with sperm DNA integrity: Selection of high DNA integrity sperm by microfluidics sorting is critical to clinical outcomes in older patients

Study question

Does sperm DNA integrity affect clinical outcomes of ICSI?

Summary answer

Use of high DNA integrity sperm selected by microfluidics sperm sorting results in lower miscarriage rates in the patients of 39-years old and more.

What is known already

High sperm DNA damage is associated with decreased normal fertilization, embryo development and pregnancy rates, and an increased miscarriage rate. On the other hand, oocytes from older women have decreased pregnancy rate, and increased miscarriage rate because of possibility of low ability to repair sperm with DNA fragmentation, and dramatical increases of aneuploidy as women age. A microfluidic sperm selection chamber (MSS, ZyMōt™; DxNow) is a device designed to collect sperm with higher chromatin integrity than density gradient centrifugation (DGC).

Study design, size, duration

Sperm analysis was performed by sperm chromatin dispersion (SCD) test and comet assay in the same sample of 15 cases between October 2020 and February 2021. ICSI outcomes by DGC and MSS were compared with blastocyst development, and pregnancy rates in vitrified-thawed single blastocyst transfers cycle for 518 cases between August 2018 and May 2021.

Participants/materials, setting, methods

SCD test was optimized as a rapid procedure, with sperm showing a halo deemed normal, and those without a halo abnormal. Comet assay results were analyzed using CometScore 2.0, with comparison of %Tail DNA. ICSI outcomes were analyzed using multiple logistics regressions of male and female ages.

Main results and the role of chance

We found a positive correlation between male age and sperm DNA fragmentation rates in raw semen using SCD test (r = 0.70) and Comet assay (r = 0.42). Higher DNA integrity sperm could select using MSS than DGC. In this study with ICSI outcomes, 170 of 318 (53.5%) blastocyst transfers resulted in pregnancy, and 49 (28.8%) subsequently miscarried. The data were classified according to less than or more than 39 years old of male age detected by multiple logistics regressions. In patients with ≥39 years of male age, the female age was significantly higher and blastocyst and pregnancy rates were significantly lower, and the miscarriage rate was significantly higher than &lt;39 years of male age. Since sperm DNA fragmentation increased in accordance with male age, we compared MSS and DGC in the patients with male age ≥39 years. There was no significant difference in blastocyst, pregnancy, and miscarriage rates in female age &lt;39 years. While in ≥ 39 years of female age, blastocyst and pregnancy rates in MSS were not significantly different from DGC, but the miscarriage rate in MSS was significantly lower than in DGC (27.3 vs. 57.1%).

Limitations, reasons for caution

The sample size for each study was small. Analysis of sperm DNA fragmentation and samples in ICSI outcomes were not the same. The retrospective nature of ICSI outcomes in this study does not allow controlling of unknown confounders.

Wider implications of the findings

Sperm DNA fragmentation depended on male age affected fertility outcomes. However, when male age is higher, masking the effect of male age by female age. In this study, we found out the improvement of ICSI outcome by using high DNA integrity sperm selected by MSS in both ≥39 years.

Trial registration number

Not applicable

Paracrine effect of the stromal vascular fraction containing M2 macrophages on human chondrocytes through the Smad2/3 signaling pathway

The adipose-derived stromal vascular fraction (SVF) is composed of a heterogeneous mix of adipose-derived stem cells (ADSCs), macrophages, pericytes, fibroblasts, blood, and other cells. Previous studies have found that the paracrine effects of SVF cells may be therapeutic, but their role in osteoarthritis treatment remains unclear. This study aimed to investigate the therapeutic effect of SVF cells on chondrocytes. Chondrocytes were seeded on culture plates alone (control) or cocultured with SVF or ADSCs on cell culture inserts. After 48 h of coculture, chondrocyte collagen II, tissue inhibitors of metalloproteinases-3 (TIMP-3), and matrix metalloproteinases-13 (MMP-13) messenger RNA (mRNA) expression levels were evaluated using reverse-transcription polymerase chain reaction, and the transforming growth factor-β (TGF-β) levels in the supernatant were measured using ELISA. Immunohistochemical staining and flow cytometry were used to evaluate the macrophages in the SVF. These macrophages were characterized according to phenotype using the F4/80, CD86, and CD163 markers. To determine whether the Smad2/3 signaling pathways were involved, the chondrocytes were pre-treated with a Smad2/3 phosphorylation inhibitor and stimulated with the SVF, and then Smad2/3 phosphorylation levels were analyzed using western blot. The mRNA expression levels of various paracrine factors and chondrocyte pellet size were also assessed. Collagen II and TIMP-3 expression were higher in the SVF group than in the ADSC group and controls, while MMP-13 expression was the highest in the ADSC group and the lowest in the controls. TGF-β levels in the SVF group were also elevated. Immunohistochemical staining and flow cytometry revealed that the macrophages in the SVF were of the anti-inflammatory phenotype. Western blot analysis showed that the SVF increased Smad2/3 phosphorylation, while Smad2/3 inhibitors decreased phosphorylation. Smad2/3 inhibitors also reduced the expression of various other paracrine factors and decreased chondrocyte pellet size. These findings suggested that the paracrine effect of heterogeneous cells, such as anti-inflammatory macrophages, in the SVF partly supports chondrocyte regeneration through TGF-β-induced Smad2/3 phosphorylation.

Iguratimod Versus Salazosulfapyridine in Rheumatoid Arthritis Patients with an Inadequate Response to Methotrexate: Adjusted with Propensity Score Matching

OBJECTIVES

Methotrexate (MTX) is recommended as a first-line conventional synthetic disease-modifying anti-rheumatic drug (csDMARD) for treating rheumatoid arthritis (RA). No studies have established which csDMARDs are useful as add-on drugs for RA patients with an inadequate response (IR) to MTX. This retrospective study sought to identify an add-on csDMARD treatment strategy for RA patients with MTX-IR.

PATIENTS AND METHODS

We collected the cases of RA patients treated with salazosulfapyridine (SASP) or iguratimod (IGU) as the additional csDMARD for MTX-IR during a 24-month follow-up at four institutions in Japan. We performed propensity score matching to evaluate the retention rate, clinical efficacy, and safety profile (n=54, each group).

RESULTS

The retention rates at 24 months of combination therapy in the patients with any-reason discontinuations were 38.5% (MTX+SASP group) and 67.8% (MTX+IGU group). At 3 and 6 months of follow-up, the MTX+IGU group's DAS28-CRP was significantly decreased versus the MTX+SASP group, and at 3 months the MTX+IGU group's good-responder percentage (22.9%) was significantly higher versus the MTX+SASP group's (10.7%). Conversely, compared to the MTX+SASP group, the MTX+IGU group showed a greater reduction in the eGFR from baseline after 3 months during follow-up.

CONCLUSIONS

IGU is a useful add-on csDMARD for RA patients with MTX-IR; its high retention rate and good clinical response make it a useful combination therapy for controlling RA disease activity. However, the renal function of these patients should be monitored during follow-up.

POS1441 INFLUENCE OF ENVIRONMENTAL AND GENETIC FACTORS ON SERUM IGG4 DURING HEALTH CHECKUPS IN NAGASAKI ISLAND STUDY

Background

Although serum IgG4 levels are important for the diagnosis of IgG4-related diseases (IgG4-RD), few studies have validated IgG4 levels in healthy individuals in large resident medical examination cohorts and investigated background factors associated with serum IgG4.

A report on genetic factors shows that HLA loci associate with IgG4-RD found in Japanese nation-wide IgG4-RD registry1). However, environmental and genetic factors related to the elevated serum IgG4 levels, which may closely associate with development of IgG4-RD, have previously been unclear in healthy subjects. The nephelometric immunoassay (NIA) is conventionally used to measure IgG4, but it requires a relatively large amount of serum. The magnetic bead panel assay (MBA), which can evaluate IgG4 levels with only a few ml of serum, has an advantage compared with NIA regarding to required sample volume, but the correlation between the two methods is unclear.

Objectives

First, we attempted to verify the accuracy of the MBA compared to the standard NIA in the first cohort. Next, we examined the relationship between IgG4 measured by the MBA and background information of healthy subjects to identify variables that correlate with serum IgG4 in the second cohort.

Methods

First, Kanazawa University collected 947 samples from the resident health examination, and IgG4 levels were measured by both MBA and NIA, and the correlation between the two was verified using Spearman’s rank correlation coefficient (first cohort). Next (second cohort), serum IgG4 of 3240 samples of Nagasaki Island Study (NaIS), which had started in 2014 collaborating among Nagasaki University and Goto City, Nagasaki Prefecture, intended for research of varying conditions and diseases including IgG4-RD, were then measured by MBA. These subjects were stratified into the two groups as IgG4-high and IgG4-within normal limit using the aforementioned cutoff values, and compared with background information such as age, gender, drinking, smoking, uric acid, serum creatinine, comorbidities and HLA typing, including DRB1*04:06, *04:03, *04:05, *04:10 as disease-susceptibility gene, DRB1*09:01 and DQB1*03:03 as protective gene1).

Results

IgG4 by MBA correlated well with IgG4 by NIA (r=0.94, p-value<0.001) which was determined from Kanazawa samples (N=947). 1,463.6 mg/mL of IgG4 of MBA corresponded to 135 mg/dl, the normal cut-off value for IgG4 by NIA. In the analysis of NaIS samples (N=3240), the overall high IgG4 positivity rate was 6.3%. Multivariable analysis including age, gender, smoking and drinking, led by univariate analysis, showed that gender and smoking were significantly associated with high serum IgG4 positivity (male: odds ratio = 1.8, 95%CI =1.2-2.7, p = 0.009, smoking: odds ratio = 1.7, 95%CI =1.1-2.5, p = 0.012). There was no association between high serum IgG4 level and HLA genotyping.

Conclusion

We concluded that MBA is a good method to measure serum IgG4 even by the very small sample volume. In our study, the prevalence of serum IgG4 positivity was high tendency than previous report2). Our data showed that male and smoking are independent factors associated with high serum IgG4 positivity. There were no association between serum IgG4 level and HLA genotyping in healthy subjects. Further comprehensive investigation is necessary to clarify high risk subjects who will develop IgG4-RD.

References

[1]Terao C, et al. Lancet Rheumatol 2019;1: e14–22.

[2]Carballo I, et al. PLoS One. 2016;11: e0149330.

Disclosure of Interests

None declared

AB0071 ANTI-ACETYLATED PROTEIN IgM-ANTIBODIES AS THE STARTING POINT OF AUTOANTIBODY FORMATION IN RHEUMATOID ARTHRITIS?

Background

Anti-modified protein antibodies (AMPA) are an important hallmark of rheumatoid arthritis (RA) and the fact that they have consistently been found to develop years before disease onset, has provided important insights into the immunopathology underlying RA. In (auto)antibody development, IgM is the first isotype to be produced. However, it is unclear whether IgM-autoimmunity differs between AMPA targeting different post-translational modifications (citrulline, homocitrulline and acetylated residues), which could provide clues about the starting point of the AMPA response.

Objectives

We therefore investigated IgM-levels of anti-citrullinated protein antibodies (ACPA), anti-carbamylated protein antibodies (anti-CarP) and anti-acetylated protein antibodies (AAPA) in healthy individuals, non-RA and RA patients.

Methods

Autoantibodies were investigated in 2 cohorts:

1) a Japanese cohort of healthy individuals (community based Nagasaki Island study) known to be ACPA-positive (n=65) or ACPA-negative (n=197) were compared to Dutch healthy donors (n=30) and ACPA-positive RA patients (n=29). ACPA, anti-CarP and AAPA IgG were measured by ELISAs using CCP4, CHcitP4 and CAcetylP4 peptides with sequences similar to the commercial CCP2 antigen and native control peptides.

2) early arthritis patients from the Leiden Early Arthritis Clinic who had RA (n=648) or another form of arthritis (non-RA, n=555) and healthy controls (n=80). ACPA and AAPA were determined by ELISAs using CCP2 and cACP2 peptides and their native control peptides, while anti-CarP was measured on homocitrullinated versus native fetal calf serum. Mann-Whitney U-tests were performed for statistical comparisons.

Results

ACPA IgM reactivity was mainly present in established ACPA-positive RA patients (Figure 1A) and to a lesser extent in ACPA-positive healthy Japanese individuals, and non-RA arthritis patients (Figure 1D). A similar picture was observed for anti-CarP IgM reactivity, for which again highest levels were found in established RA patients (1B and 1E) and ACPA-positive compared to ACPA-negative healthy Japanese individuals (1B). Intriguingly, AAPA IgM reactivity-levels displayed a different pattern as these were comparable between healthy individuals and ACPA-positive RA patients (1C and 1F). Likewise, AAPA IgM reactivity-levels were also not increased in ACPA-positive healthy Japanese individuals, who instead had lower levels compared to their ACPA-negative counterparts. Furthermore, the AAPA IgM-reactivity levels did not differ between non-RA arthritis patients, healthy controls and RA patients (1F). AAPA IgG-levels on the other hand were clearly elevated in RA patients compared to healthy controls and non-RA arthritis patients (1G).

Conclusion

AAPA are exceptional compared to other AMPA because IgM AAPA-levels are similar among healthy individuals, non-RA arthritis and RA patients. This suggests that AAPA IgM is part of the “normal” immune repertoire and could constitute the starting point for RA-associated AMPA responses, with isotype switching and epitope spreading to other post-translational modifications leading to the typical RA-associated mature AMPA response.

Disclosure of Interests

None declared

Peri-prosthetic bone remodeling of hydroxyapatite-coated compaction short stem was not affected by stem alignment

Background

To improve implant survival through accelerated early bone remodeling during total hip arthroplasty (THA), hydroxyapatite (HA) is widely used as a bioactive coating, which is believed to enhance initial fixation by osseointegration. We aimed to investigate the relationship between stem insertion alignment and postoperative bone mineral density (BMD) changes in patients with full hydroxyapatite-coated (HA) compaction short stem and short tapered-wedge stem.

Methods

This retrospective cohort study enrolled 115 consecutive patients (115 joints) undergoing THA using the full HA compaction short (n = 59) and short tapered-wedge (n = 56) stems. Stem alignment, including anteversion, valgus, and anterior tilt were measured by a three-dimensional template using computed tomography data. Post-operative peri-prosthetic BMD was measured by dual-energy X-ray absorptiometry. The relationship between stem alignment and BMD changes in the stems was analyzed.

Results

Patterns of peri-prosthetic BMD changes were similar in both groups. Stem insertion alignments of anteversion, valgus, and anterior tilt were different between the two stem types. Stem alignment of valgus and anterior tilt did not affect peri-prosthetic BMD in either of the stem type. An absolute anteversion difference between stem anteversion and original canal anteversion caused significant peri-prosthetic BMD loss in Gruen zones one and seven in the tapered-wedge stem. However, stem alignment of absolute anteversion difference did not affect BMD changes in the HA compaction stem.

Conclusions

Peri-prosthetic bone remodeling remained unaffected by stem alignment after THA with the new short full HA compaction stem.

Evolution of anti-modified protein antibody responses can be driven by consecutive exposure to different post-translational modifications

Background

Besides anti-citrullinated protein antibodies (ACPA), rheumatoid arthritis patients (RA) often display autoantibody reactivities against other post-translationally modified (PTM) proteins, more specifically carbamylated and acetylated proteins. Immunizing mice with one particular PTM results in an anti-modified protein antibody (AMPA) response recognizing different PTM-antigens. Furthermore, human AMPA, isolated based on their reactivity to one PTM, cross-react with other PTMs. However, it is unclear whether the AMPA-reactivity profile is “fixed” in time or whether consecutive exposure to different PTMs can shape the evolving AMPA response towards a particular PTM.

Methods

Longitudinally collected serum samples of 8 human individuals at risk of RA and 5 with early RA were tested with ELISA, and titers were analyzed to investigate the evolution of the AMPA responses over time. Mice (13 per immunization group in total) were immunized with acetylated (or carbamylated) protein (ovalbumin) twice or cross-immunized with an acetylated and then a carbamylated protein (or vice versa) and their serum was analyzed for AMPA responses.

Results

Human data illustrated dynamic changes in AMPA-reactivity profiles in both individuals at risk of RA and in early RA patients. Mice immunized with either solely acetylated or carbamylated ovalbumin (AcOVA or CaOVA) developed reactivity against both acetylated and carbamylated antigens. Irrespective of the PTM-antigen used for the first immunization, a booster immunization with an antigen bearing the other PTM resulted in increased titers to the second/booster PTM. Furthermore, cross-immunization skewed the overall AMPA-response profile towards a relatively higher reactivity against the “booster” PTM.

Conclusions

The relationship between different reactivities within the AMPA response is dynamic. The initial exposure to a PTM-antigen induces cross-reactive responses that can be boosted by an antigen bearing this or other PTMs, indicating the formation of cross-reactive immunological memory. Upon subsequent exposure to an antigen bearing another type of PTM, the overall reactivity pattern can be skewed towards better recognition of the later encountered PTM. These data might explain temporal differences in the AMPA-response profile and point to the possibility that the PTM responsible for the initiation of the AMPA response may differ from the PTM predominantly recognized later in time.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13075-021-02687-5.

Early tumor response assessment may avoid serious immune-related adverse events in nivolumab and ipilimumab combination therapy for stage IV melanoma

Nivolumab and ipilimumab combination therapy is one of the most promising treatments for patients with melanoma. However, this combination therapy is highly toxic and causes serious adverse events (SAEs) in more than half of the patients.

Preoperative varus deformity of the knee affects the intraoperative joint gap in unicompartmental knee arthroplasty

BACKGROUND

It is generally believed that contraction of the soft tissue structures on the medial side may occur in the knee with severe varus deformity. However, the relationship between the severity of varus deformity of the knee and the intraoperative soft tissue balance in unicompartmental knee arthroplasty (UKA) has not been well reported thus far.

METHODS

One hundred and three consecutive medial UKAs were enrolled. After the femoral trial prosthesis was placed, the component gap was measured at 10° (extension) and 120° (flexion) of flexion using a UKA tensor. The pre-osteotomy gap was then calculated from the thickness of the bone cut. Paired Student's t-test was used to compare the component gap, as well as the pre-osteotomy gap, in extension and those in flexion. The relationship between the preoperative Hip-Knee-Ankle (HKA) angle and the pre-osteotomy gap was analysed using Pearson's correlation coefficient and simple linear regression analysis.

RESULTS

The component gap in extension was significantly smaller than that in flexion while the pre-osteotomy gap in extension was significantly wider than that in flexion. There was a positive correlation between the severity of varus deformation in preoperative knee and the pre-osteotomy gap in extension, while there was no correlation between the preoperative HKA angle and the pre-osteotomy gap in flexion.

CONCLUSIONS

The tension of the medial tightness does not correlate with the degree of preoperative varus deformity in UKA.

Expression profiling of genes in rheumatoid fibroblast-like synoviocytes regulated by Fas ligand via cDNA microarray analysis

Rheumatoid arthritis (RA) is an autoimmune disease that causes chronic inflammation in synovial tissues. Hyperplasia of synovial tissues leads to the formation of pannus that invades the joint cartilage and bone, resulting in joint destruction. Fas ligand (FasL), which is a member of the tumor necrosis factor superfamily, contributes to the pathogenesis of autoimmune diseases, including RA. The current study attempted to identify genes whose expressions in rheumatoid fibroblast-like synoviocytes (RA-FLS) were regulated by FasL, using cDNA microarray. A total of four individual lines of primary cultured RA-FLS were incubated either with recombinant human FasL protein or PBS as an unstimulated control for 12 h. Gene expression was detected using a microarray assay. The results revealed the expression profiles of genes in RA-FLS regulated by Fas and investigated the functions of the genes that were regulated. Among the genes in this profile, the mRNA expression changes of the following genes were indicated to be of note using RT-qPCR: Dual specificity phosphatase 6, epiregulin, interleukin 11, angiopoietin-like 7, protein inhibitor of activated STAT 2 and growth differentiation factor 5. These genes may affect the pathogenesis of RA by affecting apoptosis, proliferation, cytokine production, cytokine-induced inflammation, intracellular signaling, angiogenesis, bone destruction and chondrogenesis. To the best of our knowledge, the current study is the first study to reveal the expression profile of genes in RA-FLS regulated by FasL. The data demonstrated that FasL may regulate the expression of a number of key molecules in RA-FLS, thus affecting RA pathogenesis. Further studies of the genes detected may improve the understanding of RA pathogenesis and provide novel treatment targets for RA.

Susceptibility of cyclin-dependent kinase inhibitor 1-deficient mice to rheumatoid arthritis arising from interleukin-1β-induced inflammation

We recently reported that cyclin-dependent kinase inhibitor 1 (p21) deficiency induces osteoarthritis susceptibility. Here, we determined the mechanism underlying the effect of p21 in synovial and cartilage tissues in RA. The knee joints of p21-knockout (p21^-/-) (n = 16) and wild type C57BL/6 (p21^+/+) mice (n = 16) served as in vivo models of collagen antibody-induced arthritis (CAIA). Arthritis severity was evaluated by immunological and histological analyses. The response of p21 small-interfering RNA (siRNA)-treated human RA FLSs (n = 5 per group) to interleukin (IL)-1β stimulation was determined in vitro. Arthritis scores were higher in p21^-/- mice than in p21^+/+ mice. More severe synovitis, earlier loss of Safranin-O staining, and cartilage destruction were observed in p21^-/- mice compared to p21^+/+ mice. p21^-/- mice expressed higher levels of IL-1β, TNF-α, F4/80, CD86, p-IKKα/β, and matrix metalloproteinases (MMPs) in cartilage and synovial tissues via IL-1β-induced NF-kB signaling. IL-1β stimulation significantly increased IL-6, IL-8, and MMP expression, and enhanced IKKα/β and IκBα phosphorylation in human FLSs. p21-deficient CAIA mice are susceptible to RA phenotype alterations, including joint cartilage destruction and severe synovitis. Therefore, p21 may have a regulatory role in inflammatory cytokine production including IL-1β, IL-6, and TNF-α.

POS1429 ORAL DYSBIOSIS REFLECTS THE IMMUNOLOGICAL ALTERATION OF RA REGARDING TO HLA DRB1*SE, ACPA AND CIGARETTE SMOKING: NAGASAKI ISLAND STUDY

Background:

Anti-citrullinated protein antibody (ACPA) production is observed in several organs even prior to the onset of rheumatoid arthritis (RA), and oral mucosa is considered to be one of the important tissues. Saliva is considered to reflect the oral microbiota(oralMB) including periodontal disease. A gene-environment interaction between cigarette smoking and shared epitope genes in HLA-DRB1*shared epitope (SE) provides a high risk of ACPA-positive RA. However, the interaction of HLA-DRB1*SE, ACPA, cigarette smoking and oralMB of RA patients remains to be elucidated.

Objectives:

We investigated that the difference of oralMB among RA patients and healthy subjects(HS) regarding to ACPA, HLA-DRB1*SE and cigarette smoking.

Methods:

The Nagasaki Island Study, which had started in 2014 collaborating with Goto City, Nagasaki Prefecture, Japan, is intended for research of the preclinical stage of RA, including ACPA, HLA genotype screening, oralMB and lifestyle habit. Both of blood and salivary samples were obtained from 1422 subjects out of 4276 participants in this study from 2016 to 2018. ACPA positivity was 1.7 % in total 4276 subjects. At this point, we selected 291 subjects, who were ACPA positive non-RA HS(n=22) and patients with RA (n=33, 11 subjects were ACPA positive and 22 ACPA negative, respectively) as the case, age and gender matched ACPA negative non-RA HS (n=236) as the control. In RA subjects, current smoker was n=1(3.0%) and ever smoker was n=8(24.2%). In HS, current smoker was n=29(11.2%) and ever smoker was n=55(21.3%). ACPA was measured by ELISA, and HLA genotyping was quantified by next-generation sequencing (Ref.1). The operational taxonomic unit (OTU) analysis using 16S rRNA gene sequencing were performed. The richness of microbial diversity within subject (α-diversity) was scaled via Shannon entropy. The dissimilarity between microbial community composition was calculated using Bray-Curtis distance as a scale, and differences between groups (β-diversity) were tested by permutational multivariate analysis of variance (PERMANOVA). In addition, UniFrac distance calculated in consideration of the distance on the phylogenetic tree were performed.

Results:

Median age 71 y.o., % Female 58.4 %. Among RA and non-RA subjects, not α-diversity but β-diversity was statistically smaller significantly in RA (p=0.022). In the HS, there was no decrease in α-diversity between the ACPA-positive and HLA-DRB1*SE-positive groups, but in the ACPA-positive group, there was a decrease in α-diversity in the HLA-DRB1*SE-positive group. When we compared α-diversity stratified by the presence or absence of three factors (RA, ACPA, and HLA-DRB1*SE), the RA group with ACPA and HLA-DRB1*SE positive tended to have the lowest diversity (Figure 1 lower right). RA subjects, presence of HLA-DRB1*SE did not show the difference but the tendency of lower α-diversity (p=0.29).

Conclusion:

HS with ACPA-positive HLA-DRB1*SE tended to show lower α-diversity than ACPA-positive HS and HLA-DRB1*SE positive HS. Furthermore, RA subjects with ACPA-positive HLA-DRB1*SE showed lower α-diversity than HS with ACPA-positive HLA-DRB1*SE.

Our study suggested that the oral dysbiosis may reflect the immunological status of patients with RA. Because of the small number of ACPA-positive patients, stratification by smoking history was difficult. Further examination is needed to clarify the gene-environment interaction and microbiome.

References:

[1]Kawaguchi S, et al. Methods Mol Biol 2018;1802: 22.

Disclosure of Interests:

None declared

POS0386 EVOLUTION OF ANTI-MODIFIED PROTEIN ANTIBODY RESPONSES CAN BE DRIVEN BY CONSECUTIVE EXPOSURE TO DIFFERENT POST-TRANSLATIONAL MODIFICATIONS

Background:

Besides anti-citrullinated protein antibodies (ACPA), rheumatoid arthritis patients (RA) often display autoantibody reactivities against other post-translationally modified (PTM) proteins, more specifically carbamylated and acetylated proteins. Immunizing mice with one PTM results in an anti-modified protein antibody (AMPA) response recognizing multiple PTMs. Furthermore, human AMPA, isolated based on their reactivity to one PTM, cross-react with other PTMs at the monoclonal and polyclonal level. However, it is unclear whether the AMPA reactivity profile is “fixed” in time, or whether consecutive exposure to different PTMs can shape the evolving AMPA-response.

Objectives:

To investigate the evolution of the AMPA response in mice with controlled exposure to PTMs as well as in AMPA-positive humans.

Methods:

Mice were immunized with acetylated (or carbamylated) protein (ovalbumin) twice or cross-immunized with an acetylated and then a carbamylated protein (or vice versa) and their serum was analyzed for AMPA responses with ELISA using a different backbone protein (fibrinogen) bearing the same modifications. Longitudinally collected serum samples of human individuals at risk of RA and with early RA were tested to investigate the evolution of the AMPA responses in humans.

Results:

Mice immunized twice with either solely acetylated or solely carbamylated ovalbumin (AcOVA or CaOVA) developed reactivity against both acetylated and carbamylated antigens. Irrespective of the PTM used for the first immunization, a booster immunization with the other PTM resulted in increased titers to the second/booster PTM (Figure 1A), suggesting that immunization with a defined PTM-antigen leads to the generation of anti-PTM memory B cells able to cross-recognize other PTMs. Furthermore, immunizing with CaOVA and boosting with AcOVA (or vice versa) skewed the overall AMPA-response profile towards a relatively higher reactivity against the “booster” PTM (Figure 1B). Human data also illustrated dynamic changes in AMPA reactivity profiles in both individuals at risk of RA and in early RA patients (not shown).

Conclusion:

The relationship between different reactivities within the AMPA response is dynamic. The initial exposure to a PTM antigen induces cross-reactive response that can be boosted by the same or other PTMs. The overall reactivity pattern can be skewed by subsequent exposure to other PTMs. These data might explain temporal changes in the reactivity profile of the AMPA response and point to the possibility that the PTM responsible for the initiation of the AMPA response may differ from the PTM predominantly recognized later in time.

Disclosure of Interests:

None declared

Modern femoral component design in total knee arthroplasty shows a lower patellar contact force during knee flexion compared with its predecessor

BACKGROUND

The relationship between the femoral component design in total knee arthroplasty (TKA) and the patellofemoral contact force, as well as the soft tissue balance, has not been well reported thus far.

METHODS

Twenty-eight mobile-bearing posterior-stabilized (PS) TKAs using the traditional model (PFC Sigma) and 27 mobile-bearing PS TKAs using the latest model (Attune) were included. Surgeries were performed using the measured resection technique assisted with the computed tomography (CT)-based free-hand navigation system. After all the trial components were placed, patellar contact forces on the medial and lateral sides were measured using two uniaxial ultrathin force transducers with the knee at 0°, 10°, 30°, 60°, 90°, 120°, and 135° of flexion. The joint component gap and the varus ligament balance of the femorotibial joint were also measured. The non-paired Student's t-test was conducted to compare the values of the two groups.

RESULTS

The medial patellar contact force was significantly lower for Attune group than for PFC Sigma group at 120° of knee flexion (P = 0.0058). The lateral patellar contact force was also significantly lower for Attune group than PFC Sigma group at 120° and 135° of knee flexion (P = 0.0068 and P = 0.036). The joint component gap, as well as the varus ligament balance, showed no statistically significant difference between the two groups.

CONCLUSIONS

Reduced thickness and width of the anterior flange of the femoral component in the Attune may play a role in low patellar contact force.

Subsequent shock delivery and outcomes in out-of-hospital cardiac arrests with initial unshockable rhythm

Funding Acknowledgements

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): The Japan Society for the Promotion of Science (Grant-in-Aid for Scientific Research)

Background

The conversion from initial non-shockable to shockable rhythms during cardiopulmonary resuscitation (CPR) by emergency medical service (EMS) providers may be associated with neurologically intact survival after out-of-hospital cardiac arrest (OHCA). However, the prognostic significance of rhythm conversion according to the type of initial nonshockable rhythm is unclear.

Purpose

To determine the association between shock after conversion to shockable rhythm with neurologically intact survival after OHCA and shock delivery time (time from EMS-initiated CPR to first shock delivery) in patients with two types of initial unshockable rhythm.

Methods

We analyzed the records of 90,334 adult patients with witnessed OHCA of cardiac origin who were treated by EMS providers and had an initial unshockable rhythm. Data were obtained from a prospectively recorded Japanese nationwide Utstein-style database for a 5-year period (2013–2017). The primary outcome was 1-month neurologically intact survival, defined as a cerebral performance categories score from 1 to 2. Patients were divided into initial pulseless electrical activity (PEA) (n = 37,977 [42.0%]) and initial asystole (n = 52,357 [58.0%]) groups.

Results

In the initial PEA group, the crude rate of 1-month neurologically intact survival was significantly higher in the subsequently shocked than in the non-shocked patients (4.2% [121/2,896]) vs. 2.4% [857/35,081], p &lt;0.0001). After adjustment for ten prehospital variables, the adjusted odds ratios (aORs) of subsequent shock for 1-month neurologically intact survival compared to no shock delivery were as follows: shock delivery time &lt;10 min, 2.21 (95% confidence interval [CI], 1.77–2.77, p&lt; 0.0001); 10–14 min, 1.43 (0.89–2.28, p = 0.14); and ≥15 min, 0.36 (0.16–0.81; p = 0.013). In the initial asystole group, the crude rate of 1-month neurologically intact survival was significantly higher in the subsequently shocked than in the non-shocked (1.7% [47/2,687] vs. 0.4% [203/49,670], p &lt;0.0001). A multivariate logistic regression model showed that subsequent shock with a shock delivery time &lt;10 min was associated with increased odds of neurologically intact survival compared to no shock delivery (aOR, 5.67; 95% CI, 3.92–8.18; p &lt;0.0001). However, there were no significant differences in neurological outcomes between subsequently shocked and non-shocked patients when the shock delivery time was 10–14 min (p = 0.21) or ≥15 min (p = 0.91).

Conclusions

In patients with witnessed OHCA of cardiac origin and initial nonshockable rhythm, subsequent shock after conversion to shockable rhythm during CPR was associated with increased odds of 1-month neurologically intact survival only when shock was delivered &lt;10 min from EMS-initiated CPR, regardless of the type of initial rhythm. Further, in patients with initial PEA, subsequent shock was associated with decreased odds of neurologically intact survival when shock was delivered ≥15 min from EMS-initiated CPR.

Association of subsequent shock after conversion to shockable rhythm with outcomes stratified by the type of initial non-shockable rhythm in children with out-of-hospital cardiac arrest

Funding Acknowledgements

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): The Japan Society for the Promotion of Science (Grant-in-Aid for Scientific Research)

Background/Introduction: The rhythm conversion from initial non-shockable to shockable rhythm during cardiopulmonary resuscitation (CPR) by emergency medical services (EMS) providers may be associated with neurologically intact survival after out-of-hospital cardiac arrest (OHCA) in children with an initial non-shockable rhythm. However, the prognostic significance of rhythm conversion stratified by the type of initial non-shockable rhythm is still unclear.

Purpose

We aimed to investigate the association of subsequent shock after rhythm conversion to shockable rhythm with neurologically intact survival and shock delivery time (time from EMS-initiated CPR to first shock delivery) by the type of initial non-shockable rhythm in children with OHCA.

Methods

We analysed the records of 19,095 children (age &lt;18 years) with OHCA treated by EMS providers. Data were obtained from a prospectively recorded Japanese nationwide Utstein-style database for a 13-year period (2005–2017). The primary outcome measure was 1-month neurologically intact survival, defined as cerebral performance category score of 1 to 2. Patients were divided into the initial pulseless electrical activity (PEA) (n = 3,326 [17.4%]) and initial asystole (n = 15,769 [82.6%]) groups.

Results

The proportion of patients who received subsequent shock after conversion to shockable rhythm was significantly higher in the initial PEA than in the initial asystole groups (3.3% [109/3,326] vs. 1.4% [227/15,769], p &lt; 0.0001). The shock delivery time was significantly shorter in the initial PEA than in the initial asystole groups (median [IQR], 8 min [5 min – 12 min] vs. 10 min [6 min – 16 min], p &lt; 0.01). Among the initial PEA patients, there was no significant difference between subsequently shocked (10.0% [11/109]) and subsequently non-shocked patients (6.0% [192/3,217], p = 0.10) regarding the rate of 1-month neurologically intact survival. However, after adjusting for 9 pre-hospital variables, subsequent shock with a delivery time of &lt;10 min was associated with increased odds of neurologically intact survival compared with no shock delivery (adjusted odds ratio [OR], 2.45; 95% confidence interval [CI], 1.16–5.16], p = 0.018). Among the initial asystole patients, the rate of 1-month neurologically intact survival was significantly higher in the subsequently shocked (4.4% [10/227]) than in the subsequently non-shocked (0.7% [106/15,542], p &lt; 0.0001). A multivariate logistic regression model showed that subsequent shock with a delivery time of &lt;10 min was associated with increased odds of neurologically intact survival compared with no shock delivery (adjusted OR, 9.77 [95% CI, 4.2–22.5], p &lt; 0.0001).

Conclusions

In children with OHCA with an initial non-shockable rhythm, subsequent shock after conversion to shockable rhythm during CPR was associated with increased odds of 1-month neurologically intact survival only when shock was delivered &lt;10 min from EMS-initiated CPR regardless of the type of initial rhythm.

Antibacterial properties of phenothiazine derivatives against multidrug-resistant Acinetobacter baumannii strains

AIM

As options to treat recalcitrant bacterial infections which are increasingly limited due to multidrug-resistant strains, searching for new, effective antibacterial compounds is necessary. One strategy is to generate treatment alternatives by drug repurposing.

METHODS AND RESULTS

In this work, phenotypic microarrays were used for the screening of miscellaneous compounds against the growth and biofilm formation of Acinetobacter baumannii, an important emergent multidrug-resistant opportunistic pathogen. The results showed that the phenothiazine derivatives, such as promethazine, trifluoperazine, thioridazine, and chlorpromazine, inhibited the growth of antibiotic-sensitive and multidrug-resistant strains (showing minimal inhibitory concentrations ranging from 0·05 to 0·6 g l^-1 and minimal bactericidal concentrations ranging from 0·1 to 2·5 g l^-1 ). All phenothiazine derivatives were active against biofilm cells (with minimal biofilm eradication concentrations ranging from 0·5 to >3 g l^-1 ). Chlorpromazine promoted reactive oxigen species (ROS) production, and cell membrane and DNA damage. Chlorpromazine showed synergy with antibiotics such as ceftazidime, meropenem, and colistin and was an effective treatment for experimentally infected Galleria mellonella when combined with ceftazidime.

CONCLUSIONS

It was demonstrated that phenothiazine derivatives, especially chlorpromazine, are drugs with attractive antibacterial properties against nosocomial MDR strains of A. baumannii, by generating ROS and cell membrane and DNA damage.

SIGNIFICANCE AND IMPACT OF THE STUDY

The present study indicates that repurposing phenothiazine derivatives for treating recalcitrant infections by A. baumannii could be promising.

Comparison of clinical and biomechanical outcomes between the kinematic and mechanical alignment methods in total knee arthroplasty: Protocol for a multicenter randomized controlled trial

Introduction

The concept of anatomic restoration has garnered considerable interest in the form of kinematically aligned total knee arthroplasty (KA-TKA). KA-TKAs have been reported to reproduce natural alignment and kinematics. However, few randomized controlled trials (RCTs) have compared the biomechanical outcomes and the long-term clinical outcomes of KA-TKA with those of mechanically aligned TKA (MA-TKA). We aim to investigate the long-term clinical and biomechanical effects of KA-TKA and to determine whether KA-TKA or MA-TKA is more appropriate for primary TKA.

Methods

This trial will compare clinical and biomechanical outcomes of KA-TKA to those of MA-TKA. Two hundred patients will be enrolled in the RCT and randomized into KA-TKA or MA-TKA groups. Both the groups will be evaluated 1 week before the operation, on the day of the operation, 6 months after the operation, and 1, 5, and 10 years after the operation. The primary outcome is the difference between preoperative and 1-year postoperative functional activity scores of the 2011 Knee Society Score (2011 KSS) in both groups as well as the differences between the scores of both groups. The secondary outcomes will include differences in symptom, satisfaction, and expectation scores of the 2011 KSS, intraoperative kinematics evaluation, postoperative clinical outcomes and complications, pre- and postoperative gait analyses and radiograph evaluations between both KA-TKA and MA-TKA.

Cryopreserved human adipose-derived stromal vascular fraction maintains fracture healing potential via angiogenesis and osteogenesis in an immunodeficient rat model

Background

Novel therapeutic strategies for the healing of nonunion, which has serious effects on the quality of life of patients, are needed. We evaluated the therapeutic effect of local transplantation of human stromal vascular fraction (SVF) cells on fracture healing in a rat non-healing fracture model and compared the effects between freshly isolated (F) and cryopreserved (C)-SVFs.

Methods

Non-healing fracture model was induced in the femur of female immunodeficient rats (F344/N Jcl rnu/rnu) with cauterizing periosteum. Immediately after the creation of non-healing fracture, rats received local transplantation of F and C-SVFs suspended in phosphate-buffered saline (PBS) or the same volume of PBS without cells using the same scaffold as a control group. During 8 weeks post-surgery, radiologic, histological, immunohistochemical, and biomechanical analyses were performed to evaluate fracture healing. The comparison of radiological results was performed with a chi-square test, and the multiple comparisons of immunohistochemical, histological, and biomechanical results among groups were made using a one-way analysis of variance. A probability value of 0.05 was considered to denote statistical significance.

Results

At week 8, in 60% of animals receiving F-SVF cells and in 50% of animals receiving C-SVF cells, the fracture radiologically healed with bone union whereas nonunion was observed in the control group. The healing potential was also confirmed by histological and biomechanical assessments. One of the mechanisms underlying healing involving intrinsic angiogenesis/osteogenesis was enhanced in F- and C-SVF groups compared with that in the control group. Human cell-derived vasculogenesis/osteogenesis, which was also confirmed in an in vitro differentiation assay, was also enhanced in the F- and C-SVF groups compared with that in the control groups and could be another mechanism for healing.

Conclusions

SVF cells can enhance bone healing and cryopreserved cells have almost equal potential as fresh cells. SVF cells can be used for improving nonunion bone fracture healing as an alternative to other mesenchymal stem cells and the effect of SVF cells can be maintained under cryopreservation.

A genome-wide association study identifying the SNPs predictive of rapid joint destruction in patients with rheumatoid arthritis

Rheumatoid arthritis (RA) is a common chronic autoimmune disease leading to joint destruction. The aim of the present study was to identify the genomic factors predictive of susceptibility to joint destruction in patients with RA by performing a genome-wide association study of genetic variants, including single nucleotide polymorphisms (SNPs). The study sample included 228 patients with a diagnosis of RA in the past 5 years. Patients were classified into rapid (total Sharp score/years of RA, ≥50) and slow (total Sharp score/years of RA, <50) joint destruction groups for analysis. The association between the genome-wide SNP analysis and joint destruction was evaluated. The following SNPs were strongly associated with rapid radiographic joint destruction: rs2295926 (P<1x10^-7), belonging to the N-acetylgalactosaminyltransferase 12 (GALNT12) gene and rs11958855 (P<1x10^-6), belonging to the KCNN2 gene (associated with the potassium calcium-activated channel subfamily). The identification of genetic predictors of rapid joint destruction in RA (GALNT12 and KCNN2) may provide information regarding potential therapeutic targets, and this information may be used to assist in the management RA disease progression, thereby improving the functional outcomes for patients.

Succinyl-CoA Ligase Deficiency in Pro-inflammatory and Tissue-Invasive T Cells

Autoimmune T cells in rheumatoid arthritis (RA) have a defect in mitochondrial oxygen consumption and ATP production. Here, we identified suppression of the GDP-forming β subunit of succinate-CoA ligase (SUCLG2) as an underlying abnormality. SUCLG2-deficient T cells reverted the tricarboxylic acid (TCA) cycle from the oxidative to the reductive direction, accumulated α-ketoglutarate, citrate, and acetyl-CoA (AcCoA), and differentiated into pro-inflammatory effector cells. In AcCoA^hi RA T cells, tubulin acetylation stabilized the microtubule cytoskeleton and positioned mitochondria in a perinuclear location, resulting in cellular polarization, uropod formation, T cell migration, and tissue invasion. In the tissue, SUCLG2-deficient T cells functioned as cytokine-producing effector cells and were hyperinflammatory, a defect correctable by replenishing the enzyme. Preventing T cell tubulin acetylation by tubulin acetyltransferase knockdown was sufficient to inhibit synovitis. These data link mitochondrial failure and AcCoA oversupply to autoimmune tissue inflammation.

Long-term outcomes and recurrence-free interval after the treatment of keloids with a standardized protocol

BACKGROUND

Recurrence rates of keloids have generally been reported at one time point. However, the longer the duration after treatment, the greater the likelihood that such lesions will recur. In this study, we analysed the time to recurrence during long-term follow-up.

MATERIAL AND METHODS

We retrospectively reviewed recurrence-free interval in 52 patients with keloid (age 8-79 years) who had been treated between June 2006 and January 2011 using a standardised protocol developed by our group.

RESULTS

Mean duration of follow-up was 37.5 (range, 7-120) months in patients with keloid. Kaplan-Meier survival curves revealed a statistically significant difference in recurrence-free interval between ear keloids and keloids excluding ear keloids. Recurrence rate for keloids was high in the first 2 years after treatment.

CONCLUSIONS

Kaplan-Meier analysis was useful for understanding the tendency of recurrence of keloids after treatment using a standardised protocol.