Wave packet dynamics and control in excited states of molecular nitrogen.

Wave packet interferometry with vacuum ultraviolet light has been used to probe a complex region of the electronic spectrum of molecular nitrogen, N2. Wave packets of Rydberg and valence states were excited by using double pulses of vacuum ultraviolet (VUV), free-electron-laser (FEL) light. These wave packets were composed of contributions from multiple electronic states with a moderate principal quantum number (n ∼ 4-9) and a range of vibrational and rotational quantum numbers. The phase relationship of the two FEL pulses varied in time, but as demonstrated previously, a shot-by-shot analysis allows the spectra to be sorted according to the phase between the two pulses. The wave packets were probed by angle-resolved photoionization using an infrared pulse with a variable delay after the pair of excitation pulses. The photoelectron branching fractions and angular distributions display oscillations that depend on both the time delays and the relative phases of the VUV pulses. The combination of frequency, time delay, and phase selection provides significant control over the ionization process and ultimately improves the ability to analyze and assign complex molecular spectra.

Biosynthesis of Poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) From Glucose by Escherichia coli Through Butyryl-CoA Formation Driven by Ccr-Emd Combination.

Poly[(R)-3-hydroxybutyrate-co-(R)-3-hydroxyhexanoate] [P(3HB-co-3HHx)] is a practical kind of bacterial polyhydroxyalkanoates (PHAs). A previous study has established an artificial pathway for the biosynthesis of P(3HB-co-3HHx) from structurally unrelated sugars in Ralstonia eutropha, in which crotonyl-CoA carboxylase/reductase (Ccr) and ethylmalonyl-CoA decarboxylase (Emd) are a key combination for generation of butyryl-CoA and the following chain elongation. This study focused on the installation of the artificial pathway into Escherichia coli. The recombinant strain of E. coli JM109 harboring 11 heterologous genes including Ccr and Emd produced P(3HB-co-3HHx) composed of 14 mol% 3HHx with 41 wt% of dry cellular weight from glucose. Further investigations revealed that the C6 monomer (R)-3HHx-CoA was not supplied by (R)-specific reduction of 3-oxohexanoyl-CoA but by (R)-specific hydration of 2-hexenoyl-CoA formed through reverse ß-oxidation after the elongation from C4 to C6. While contribution of the reverse ß-oxidation to the conversion of the C4 intermediates was very limited, crotonyl-CoA, a precursor of butyryl-CoA, was generated by dehydration of (R)-3HB-CoA. Several modifications previously reported for enhancement of bioproduction in E. coli were examined for the copolyester synthesis. Elimination of the global regulator Cra or PdhR as well as the block of acetate formation resulted in poor PHA synthesis. The strain lacking RNase G accumulated more PHA but with almost no 3HHx unit. Introduction of the phosphite oxidation system for regeneration of NADPH led to copolyester synthesis with the higher cellular content and higher 3HHx composition by two-stage cultivation with phosphite than those in the absence of phosphite.

Phenotypic and functional properties of dedifferentiated fat cells derived from infrapatellar fat pad.

INTRODUCTION: Mature adipocyte-derived dedifferentiated fat cells (DFATs) are mesenchymal stem cell (MSC)-like cells with high proliferative ability and multilineage differentiation potential. In this study, we first examined whether DFATs can be prepared from infrapatellar fat pad (IFP) and then compared phenotypic and functional properties of IFP-derived DFATs (IFP-DFATs) with those of subcutaneous adipose tissue (SC)-derived DFATs (SC-DFATs). METHODS: Mature adipocytes isolated from IFP and SC in osteoarthritis patients (n = 7) were cultured by ceiling culture method to generate DFATs. Obtained IFP-DFATs and SC-DFATs were subjected to flow cytometric and microarray analysis to compare their immunophenotypes and gene expression profiles. Cell proliferation assay and adipogenic, osteogenic, and chondrogenic differentiation assays were performed to evaluate their functional properties. RESULTS: DFATs could be prepared from IFP and SC with similar efficiency. IFP-DFATs and SC-DFATs exhibited similar immunophenotypes (CD73+, CD90+, CD105+, CD31-, CD45-, HLA-DR-) and tri-lineage (adipogenic, osteogenic, and chondrogenic) differentiation potential, consistent with the minimal criteria for defining MSCs. Microarray analysis revealed that the gene expression profiles in IFP-DFATs were very similar to those in SC-DFATs, although there were certain number of genes that showed different levels of expression. The proliferative activity in IFP-DFATs was significantly (p < 0.05) higher than that in the SC-DFATs. IFP-DFATs showed higher chondrogenic differentiation potential than SC-DFATs in regard to production of soluble galactosaminogalactan and gene expression of type II collagen. CONCLUSIONS: IFP-DFATs showed higher cellular proliferative potential and higher chondrogenic differentiation capacity than SC-DFATs. IFP-DFAT cells may be an attractive cell source for chondrogenic regeneration.

Time-resolved photoelectron imaging of complex resonances in molecular nitrogen.

We have used the FERMI free-electron laser to perform time-resolved photoelectron imaging experiments on a complex group of resonances near 15.38 eV in the absorption spectrum of molecular nitrogen, N2, under jet-cooled conditions. The new data complement and extend the earlier work of Fushitani et al. [Opt. Express 27, 19702-19711 (2019)], who recorded time-resolved photoelectron spectra for this same group of resonances. Time-dependent oscillations are observed in both the photoelectron yields and the photoelectron angular distributions, providing insight into the interactions among the resonant intermediate states. In addition, for most states, we observe an exponential decay of the photoelectron yield that depends on the ionic final state. This observation can be rationalized by the different lifetimes for the intermediate states contributing to a particular ionization channel. Although there are nine resonances within the group, we show that by detecting individual photoelectron final states and their angular dependence, we can identify and differentiate quantum pathways within this complex system.

Multi-channel photodissociation and XUV-induced charge transfer dynamics in strong-field-ionized methyl iodide studied with time-resolved recoil-frame covariance imaging.

The photodissociation dynamics of strong-field ionized methyl iodide (CH3I) were probed using intense extreme ultraviolet (XUV) radiation produced by the SPring-8 Angstrom Compact free electron LAser (SACLA). Strong-field ionization and subsequent fragmentation of CH3I was initiated by an intense femtosecond infrared (IR) pulse. The ensuing fragmentation and charge transfer processes following multiple ionization by the XUV pulse at a range of pump-probe delays were followed in a multi-mass ion velocity-map imaging (VMI) experiment. Simultaneous imaging of a wide range of resultant ions allowed for additional insight into the complex dynamics by elucidating correlations between the momenta of different fragment ions using time-resolved recoil-frame covariance imaging analysis. The comprehensive picture of the photodynamics that can be extracted provides promising evidence that the techniques described here could be applied to study ultrafast photochemistry in a range of molecular systems at high count rates using state-of-the-art advanced light sources.

Solvation Structure of Li+ in Concentrated Acetonitrile and N,N-Dimethylformamide Solutions Studied by Neutron Diffraction with 6Li/7Li Isotopic Substitution Methods.

Neutron diffraction measurements on 6Li/7Li isotopically substituted 10 and 33 mol % *LiTFSA (lithium bis(trifluoromethylsulfonyl)amide)-AN-d3 (acetonitrile-d3) and 10 and 33 mol % *LiTFSA-DMF-d7(N,N-dimethylformamide-d7) solutions have been carried out in order to obtain structural insights on the first solvation shell of Li+ in highly concentrated organic solutions. Structural parameters concerning the local structure around Li+ have been determined from the least squares fitting analysis of the first-order difference function derived from the difference between carefully normalized scattering cross sections observed for 6Li-enriched and natural abundance solutions. In 10 mol % LiTFSA-AN-d3 solution, 3.25 ± 0.04 AN molecules are coordinated to Li+ with a intermolecular Li+···N(AN) distance of 2.051 ± 0.007 Å. It has been revealed that 1.67 ± 0.07 AN molecules and 2.00 ± 0.01 TFSA- are involved in the first solvation shell of Li+ in the 33 mol % LiTFSA-AN solution. The nearest neighbor Li+···NAN and Li+···OTFSA- distances are obtained to be r(Li+···N) = 2.09 ± 0.01 Å and r(Li+···O) = 1.88 ± 0.01 Å, respectively. The first solvation shell of Li+ in the 10 mol % LiTFSA-DMF-d7 solutions contains 3.4 ± 0.1 DMF molecules with an intermolecular Li+···ODMF distance of 1.95 ± 0.02 Å. In highly concentrated 33 mol % LiTFSA-DMF-d7 solutions, there are 1.3 ± 0.2 DMF molecules and 3.2 ± 0.2 TFSA- in the first solvation shell of Li+ with intermolecular distances of r(Li+···ODMF) = 1.90 ± 0.02 Å and r(Li+···OTFSA-) = 2.01 ± 0.01 Å, respectively. The Li+···TFSA- contact ion pair stably exists in highly concentrated 33 mol % LiTFSA-AN and -DMF solutions.

Activation of inflammation and resolution pathways of lipid mediators in synovial fluid from patients with severe rheumatoid arthritis compared with severe osteoarthritis.

BACKGROUND: The upregulation of the cyclooxygenase and lipoxygenase pathways of arachidonic acid is thought to be involved in the development of rheumatoid arthritis. Recently, the presence of specialized pro-resolving lipid mediators in synovial tissues from patients with osteoarthritis has been reported. OBJECTIVE: To clarify the quantitative and qualitative changes in lipid mediators in the synovium of severe rheumatoid arthritis patients, we compared the profiles of lipid mediators in synovial fluid obtained from patients with severe rheumatoid arthritis and from those with severe osteoarthritis. METHODS: We enrolled 18 patients with rheumatoid arthritis and 26 patients with osteoarthritis. All the patients had undergone total knee replacement surgery. Synovial fluid samples had been obtained during the surgery. Lipid profiling in the synovial fluid from these patients was performed using liquid chromatography-tandem mass spectrometry/mass spectrometry. RESULTS: Among the 150 oxidized fatty acids examined so far, 119 were substantially detected in synovial fluid from the patients. Not only the concentrations of pro-inflammatory lipid mediators such as prostaglandins and leukotrienes, but also those of specialized pro-resolving lipid mediators such as lipoxins, resolvins, and protectin D1 were significantly higher in synovial fluid obtained from rheumatoid arthritis patients than from synovial fluid obtained from osteoarthritis patients. CONCLUSION: The activation of both inflammation and resolution pathways of lipid mediators might be a fatty acid signature in the synovial fluid of patients with severe rheumatoid arthritis. Inflammatory, anti-inflammatory and pro-resolving mediators in synovial fluid could be good biomarkers for differentiating between severe rheumatoid arthritis and severe osteoarthritis.

Multi-particle momentum correlations extracted using covariance methods on multiple-ionization of diiodomethane molecules by soft-X-ray free-electron laser pulses.

Momenta of ions from diiodomethane molecules after multiple ionization by soft-X-ray free-electron-laser pulses are measured. Correlations between the ion momenta are extracted by covariance methods formulated for the use in multiparticle momentum-resolved ion time-of-flight spectroscopy. Femtosecond dynamics of the dissociating multiply charged diiodomethane cations is discussed and interpreted by using simulations based on a classical Coulomb explosion model including charge evolution.

Changes in radiographic findings and plantar pressure distribution following forefoot reconstructive surgery for patients with rheumatoid arthritis.

Objectives: To evaluate changes in radiographic findings and plantar pressure distribution after rheumatoid forefoot surgery.Methods: This study was performed on patients with rheumatoid arthritis (RA) who underwent Swanson implant arthroplasty for the 1st metatarsophalangeal (MTP) joint combined with shortening oblique osteotomy at the 2nd through 5th metatarsal necks (group Sw, 55 feet). The following two groups were used as controls: group NS, consisting of 75 feet in RA patients without scheduled forefoot surgery, and group HC, consisting of 24 feet in healthy female subjects. Plantar pressure distribution, and radiographic findings of hallux valgus angle, the angle between the metatarsal bones, talocalcaneal angle, calcaneal pitch angle and calcaneo-first metatarsal angle (CFMA) were measured pre- and one year postoperatively. Peak pressure was measured in nine sections.Results: Calcaneal pitch angle decreased and CFMA increased in group Sw. Peak pressure at the 1st interphalangeal joint (IP) and the 2nd and 3rd MTPs in group Sw decreased, while that at midfoot increased.Conclusion: While the clinical outcome in group Sw was favorable, postoperative longitudinal arch decreased. Postoperative peak pressure at the 2nd through 5th MTPs was comparable with that in group NS; however, it was significantly lower than that in group HC.

The Effect of Posterior Tibial Slope on Joint Gap and Range of Knee Motion in Mobile-Bearing Unicompartmental Knee Arthroplasty.

BACKGROUND: It is widely known that the posterior tibial slope (PTS) has an influence on the clinical outcome of arthroplasty. However, the influence of PTS on unicompartmental knee arthroplasty (UKA) is still not fully clear. The objective of this study is to reveal the effect PTS has on knee flexion and extension joint gap and the postoperative range of motion in mobile-bearing UKA. Moreover, we investigated an adequate PTS angle in mobile-bearing UKA. METHODS: Oxford UKA was performed so that the flexion gap would be equal to the extension gap. Correlation between the gap value difference from 90° to 120° of the knee flexion and the PTS was evaluated. Correlation between postoperative range of motion and the PTS was also evaluated to find whether a small degree of PTS would cause knee flexion restriction. RESULTS: The PTS had a moderate positive correlation with the flexion gap difference. However, the PTS had no correlation with the knee flexion angle both postoperative and 1 year after surgery. CONCLUSION: It was suggested that the degree of the PTS should not be so large to avoid joint looseness throughout every knee angle. Increasing the degree of the PTS had the potential to dislocate the bearing. Since a small degree of the PTS does not have an influence on the clinical outcome, surgeons should aim to cut the tibia with a posterior slope of less than 7°.

Transplantation of dedifferentiated fat cell-derived micromass pellets contributed to cartilage repair in the rat osteochondral defect model.

BACKGROUND: Mature adipocyte-derived dedifferentiated fat (DFAT) cells possesses the ability to proliferate effectively and the potential to differentiate into multiple linages of mesenchymal tissue; similar to adipose-derived stem cells (ASCs). The purpose of this study is to examine the effects of DFAT cell transplantation on cartilage repair in a rat model of osteochondral defects. METHODS: Full-thickness osteochondral defects were created in the knees of Sprague-Dawley rats bilaterally. Cartilage-like micromass pellets were prepared from green fluorescent protein (GFP)-labeled rat DFAT cells and subsequently transplanted into the affected right knee of these rats. Defects in the left knee were used as a control. Macroscopic and microscopic changes of treated and control defects were evaluated up to 12 weeks post-treatment with DFAT cells. To observe the transplanted cells, sectioned femurs were immunostained for GFP and type II collagen. RESULTS: DFAT cells formed micromass pellets expressing characteristics of immature cartilage in vitro. In the DFAT cell-transplanted limbs, the defects were completely filled with white micromass pellets as early as 2 weeks post-treatment. These limbs became smooth at 4 weeks. Conversely, the defects in the control limbs were still not repaired by 4 weeks. Macroscopic ICRS scores at 2 and 4 weeks were significantly higher in the DFAT cells-transplanted limbs compared to those of the control limbs. The modified O'Driscol histological scores for the DFAT cell-transplanted limbs were significantly higher than those of the control limbs at corresponding time points. GFP-positive DAFT cells were detected in the transplanted area at 2 weeks but hardly visible at 12 weeks post-operation. CONCLUSIONS: Transplantation of DFAT cell-derived micromass pellets contribute to cartilage repair in a rat osteochondral defect model. DFAT cell transplantation may be a viable therapeutic strategy for the repair of osteochondral injuries.

Teriparatide Treatment Improved Loosening of Cementless Total Knee Arthroplasty: A Case Report.

INTRODUCTION: Along with the increase of osteoporotic patients in an aging society, complications in surgeries associated with osteoporosis are also increasing. In cementless total knee arthroplasty (TKA), poor primary stability and subsequent initial loosening of the implant may be seen. CASE REPORT: The patient, a 75-year-old Asian woman with a history of osteoporosis, underwent cementless TKA. Knee radiography at 5 weeks postoperatively showed radiolucent lines outlined beneath the tibial tray and around the stem. The tibial component was considered unstable due to loosening. A 56.5 µg weekly dose of teriparatide (rh [1-34] parathyroid hormone) was administered. After 2 months of treatment, knee pain and knee swelling had disappeared. Tomosynthesis taken after 6 months of treatment confirmed complete ingrowth of the component to the bone. CONCLUSION: This case showed that a weekly teriparatide administration of 56.5 µg improved initial loosening of the tibial implant in cementless TKA. Administration of teriparatide in cases of the osteoporotic patient who has loosening in cementless TKA may be a useful adjuvant to achieve bone ingrowth again.

The dual regulation of substance P-mediated inflammation via human synovial mast cells in rheumatoid arthritis.

BACKGROUND: Neural pathways are thought to be directly involved in the pathogenesis of rheumatoid arthritis (RA). Although synovial mast cells (MCs) are activated by substance P (SP), the role of MCs in neural pathways in RA remains unknown. The aims of this study were to investigate 1) whether tachykinins are produced by synovial MCs and whether production differs in RA and osteoarthritis (OA) patients, and 2) what is the responsible receptor for SP in synovial MCs. METHODS: Synovial tissues were obtained from patients with RA or OA undergoing joint replacement surgery. Cultured synovium-derived MCs were generated by culturing dispersed synovial cells with stem cell factor. SP expression was investigated using immunofluorescence and enzyme immunoassays. Mas-related gene X2 (MrgX2) expression was reduced in human MCs using a lentiviral shRNA silencing technique. RESULTS: SP expression was localized around the cell membrane in 41% (median) of the MCs in synovium from RA but in only 7% of that from OA, suggesting the activation of MCs. Synovial MCs expressed tachykinin (TAC) 1 mRNA, the expression of which was upregulated by the aggregation of FcɛRI or the addition of aggregated IgG. However, the released SP appeared to be rapidly degraded by MC chymase. Synovial MCs were activated with SP through MrgX2 to release histamine without producing proinflammatory cytokines. CONCLUSIONS: Activated synovial MCs may rapidly degrade SP, which may downregulate the SP-mediated activation of synoviocytes in RA. On the other hand, SP activates MCs to induce inflammatory mediators, suggesting the dual regulation of SP-mediated inflammation by MCs in RA.

Union, Knee Alignment, and Clinical Outcomes of Patients Treated With Autologous Bone Grafting for Medial Tibial Defects in Primary Total Knee Arthroplasty.

Autologous bone grafting is an established method to overcome bone deficiencies in primary total knee arthroplasty (TKA). However, recently, metal augments have been used by many surgeons. Although autologous bone grafting is a common technique, few large studies have described its success in achieving bone union in primary TKA. The goal of this study was to evaluate primary TKA with autologous bone grafting for tibial defects. A total of 68 knees that had undergone arthroplasty with autologous bone grafting with more than 1 year of follow-up were evaluated. Average follow-up was 6.6 years (range, 1.2-14.6 years). The autologous bone grafting procedure attached the proximal portion of the tibial resection from the lateral side to the bone graft on the medial side with 2 screws. The prosthesis, which had a standard and nonrevision stem, was implanted with cement. Bone union was assessed with fluoroscopic radiography with a weight-bearing anteroposterior view. The rate of bone union was 97% (65 knees). Correction of preoperative alignment was achieved and maintained until final follow-up. Postoperative knee angle and knee and function scores showed significant improvement. One infection occurred, but there were no local complications, such as backout of screws or collapse of bone grafts. The authors believe that autologous bone graft within TKA is a relatively simple and effective procedure that provides good bone union. [Orthopedics. 2017; 40(4):e604-e608.].

Plantar pressure and surgical indication of toe arthroplasty for rheumatoid forefoot deformity.

OBJECTIVES: The objective of this study is to clarify the surgical indication for rheumatoid forefoot deformity according to background characteristics and plantar pressure. METHODS: Patients with rheumatoid arthritis were divided into a non-surgical group (group N) and a surgical group (group S). The former consisted of 225 ft, and the latter consisted of 88 ft. DAS28, Japanese Society for Surgery of the Foot rheumatoid arthritis foot and ankle scale (JSSF scale) and hallux valgus angle (HVA) were evaluated as background characteristics. Distribution of peak pressure as plantar pressure was measured in nine sections. RESULTS: In groups N and S, the mean DAS28 was 3.6 and 3.0, the mean JSSF scale was 81.1 and 63.0, and the mean HVA was 19.9° and 35.3°, respectively. The mean peak pressure of group S at the first and third metatarsophalangeal joints was significantly higher compared with group N. Significant differences between the two groups were also seen in Δ pressure (the difference between the maximum and minimum peak pressure values). The cut-off values were 75.0 for JSSF scale, 24.9° for HVA and 3.94 kg/cm2 for Δ pressure. CONCLUSIONS: The combined assessment of HVA and Δ pressure was found to be useful as an indication for surgical treatment of the forefoot.

Interleukin-17A expression in human synovial mast cells in rheumatoid arthritis and osteoarthritis.

BACKGROUND: Interleukin (IL)-17A plays a pivotal role in the pathogenesis of rheumatoid arthritis (RA). The expression of IL-17A in synovial mast cells (MCs) in RA and osteoarthritis (OA) has been reported, but the frequencies of IL-17A expression in synovial MCs have varied. The aim of this study was to investigate whether IL-17A expression is upregulated in human synovial MCs in RA and to elucidate the mechanism of IL-17A expression in synovial MCs. METHODS: Synovial tissues were obtained from patients with RA or OA undergoing joint replacement surgery, and synovial MCs were enzymatically dispersed. Synovium-derived cultured MCs were generated by culturing synovial cells with stem cell factor. IL-17A expression was investigated using immunofluorescence in synovial tissues. IL-17A mRNA expression and its production from MCs were examined using RT-PCR and ELISA, respectively. RESULTS: The number of IL-17A-positive ((+)) synovial MCs and the percentage of IL-17A(+) MCs among all the IL-17A(+) cells from RA patients were not significantly increased compared with those from OA subjects. The synovium-derived cultured MCs spontaneously released small amounts of IL-17A. Neither IgE- nor IgG-dependent stimulation increased IL-17A production from the MCs. IL-33, tumor necrosis factor-α, C5a, lipopolysaccharide or IL-23 plus IL-1ß did not affect IL-17A production in MCs. CONCLUSIONS: The synovial MCs are not a main source of IL-17A in RA.

Evaluation of spacer block technique using tensor device in unicompartmental knee arthroplasty.

INTRODUCTION: Mobile-bearing unicompartmental knee arthroplasty (UKA) was designed so that flexion and extension gap adjustments could achieve isometric function of the ligaments throughout ROM to prevent complications. However, achieving accurate knee balancing using a spacer block technique remains difficult since determination of the thickness of the spacer block is determined according to the feeling of the individual surgeon's hand. The objective of the study was to investigate flexion and extension medial unicompartmental knee gap kinematics in mobile-bearing UKA and to reveal the accuracy of spacer block measurement technique using a gap tensor device. MATERIALS AND METHODS: Mobile-bearing UKA was performed in 40 knees of 31 subjects using generally accepted spacer block technique so that the extension gap was made equal to the flexion gap. The extension and flexion gaps of the medial knee compartment were measured using the tensor device with 25, 50, 75, 100, 125, and 150 N of joint distraction force. The interplay gap was calculated by subtracting the thickness of the tibial prosthesis and the thickness of the selected size of bearing from the measured extension and flexion gaps. Medial compartmental joint interplay gap differences were compared among flexion and extension gaps. RESULTS: The mean flexion interplay gap was 25 N: 0.5 mm, 50 N: 1.5 mm, 75 N: 2.4 mm, 100 N: 3.1 mm, 125 N: 3.6 mm, 150 N: 4.0 mm. The mean extension interplay gap was 25 N: -0.2 mm, 50 N: 0.81 mm, 75 N: 1.7 mm, 100 N: 2.5 mm, 125 N: 3.1 mm, 150 N: 3.5 mm. The measured extension gap was shown to be significantly smaller compared with the flexion gap at every joint distraction force (P < 0.01). CONCLUSIONS: These results suggest that gap measurement using a spacer block in UKA has the potential risk that the resulting extension gap may be smaller than the flexion gap. Surgeons should adjust the flexion and extension gaps with caution to achieve good ligament function when performing mobile-bearing UKA.

Interleukin-33 synergistically enhances immune complex-induced tumor necrosis factor alpha and interleukin-8 production in cultured human synovium-derived mast cells.

BACKGROUND: Substantial evidence suggests that human synovial mast cells (MCs) are involved in the pathogenesis of rheumatoid arthritis (RA). Interleukin (IL)-33 is believed to play an important role in the pathogenesis of RA. We recently reported that FcγRI is responsible for producing abundant tumor necrosis factor alpha (TNF-α) from cultured synovium-derived MCs (SyMCs) in response to aggregated immunoglobulin G (IgG). However, whether or not IL-33 affects immune complex (IC)-induced synovial MC activation remains unknown. This study sought to evaluate the effect of IL-33 on IC-induced synovial MC activation. METHODS: Cultured SyMCs were generated by culturing synovial cells with stem cell factor. ST2 expression was analyzed using FACS and immunohistochemical techniques. Mediators released from the MCs were measured using EIAs or ELISAs. RESULTS: SyMCs obtained from patients with RA or osteoarthritis (OA) expressed ST2 on their surfaces. We confirmed the expression of ST2 in MCs using immunofluorescence staining in joint tissue obtained from RA patients. IC-triggered histamine release was not enhanced by IL-33. However, IL-33 synergistically enhanced IC-induced IL-8 and TNF-α production in SyMCs. CONCLUSIONS: ICs and IL-33 may exacerbate inflammation associated with RA by abundantly producing TNF-α and IL-8 from SyMCs.

Osteoarthritis of the patella, lateral femoral condyle and posterior medial femoral condyle correlate with range of motion.

PURPOSE: The type of osteoarthritis and the degree of severity which causes restriction of knee range of motion (ROM) is still largely unknown. The objective of this study was to analyse the location and the degree of cartilage degeneration that affect knee range of motion and the connection, if any, between femorotibial angle (FTA) and knee ROM restriction. METHODS: Four hundreds and fifty-six knees in 230 subjects with knee osteoarthritis undergoing knee arthroplasty were included. Articular surface was divided into eight sections, and cartilage degeneration was evaluated macroscopically during the operation. Cartilage degeneration was classified into four grades based on the degree of exposure of subchondral bone. A Pearson correlation was conducted between FTA and knee flexion angle to determine whether high a degree of FTA caused knee flexion restriction. A logistic regression analysis was also conducted to detect the locations and levels of cartilage degeneration causing knee flexion restriction. RESULTS: No correlation was found between FTA and flexion angle (r = -0.08). Flexion angle was not restricted with increasing FTA. Logistic regression analysis showed significant correlation between restricted knee ROM and levels of knee cartilage degeneration in the patella (odds ratio (OR) = 1.77; P = 0.01), the lateral femoral condyle (OR = 1.62; P = 0.03) and the posterior medial femoral condyle (OR = 1.80; P = 0.03). CONCLUSION: For clinical relevance, soft tissue release and osteophyte resection around the patella, lateral femoral condyle and posterior medial femoral condyle might be indicated to obtain a higher degree of knee flexion angle.

Safety of fondaparinux versus enoxaparin after TKA in Japanese patients.

Fondaparinux and enoxaparin are useful for preventing venous thromboembolism after total knee arthroplasty (TKA), but both drugs have associated complications. The purpose of this study was to clarify the risks associated with use of these drugs in Japanese patients who underwent TKA.A total of 575 patients (935 knees) underwent TKA and were retrospectively reviewed; 277 patients (454 knees) were treated with fondaparinux and 298 patients (481 knees) were treated with enoxaparin. The authors investigated the incidences of deep venous thrombosis of the lower limbs and pulmonary embolism to evaluate venous thromboembolism, knee enlargement compared with the preoperative size, incidence of subcutaneous knee hematoma, and other complications. No significant differences were observed between the 2 drugs regarding the incidences of deep venous thrombosis and pulmonary embolism. However, fondaparinux use resulted in knee enlargement (P<.0005) and subcutaneous hematoma of the knee (P=.035) significantly more often than enoxaparin use. Conversely, enoxaparin use significantly caused the elevation of alanine aminotransferase (one of the liver enzymes) at a higher rate than fondaparinux (30.1% vs 8.3%, respectively; P<.0001). However, the increased alanine aminotransferase levels were transient, and no patient exhibited symptoms of abnormal liver function, such as jaundice or cutaneous pruritus.Fondaparinux and enoxaparin were both effective in preventing venous thromboembolism in Japanese patients undergoing elective TKA. However, both drugs had some adverse effects. It is important to be aware of these potential risks when prescribing these drugs.