Synthesis and Properties of Azahomocorannulenyl Cations and Radicals.

Cycloheptatrienyl (tropyl) molecules are representative non-alternant hydrocarbons that offer interesting chemistry because of their unique structures and properties. However, there have been a limited number of polycyclic aromatic tropyl cations and radicals reported in the literature. Herein, we report the synthesis of a series of azahomocorannulene derivatives, where the key reactions are a 1,3-dipolar cycloaddition of polycyclic aromatic azomethine ylides with dibenzotropone and a subsequent palladium-catalyzed cyclization. X-ray diffraction analysis revealed that the obtained azahomocorannulenyl cation and radical adopt planar structures and exhibit unique packing structures. Their electronic and optical properties were investigated experimentally and theoretically to reveal their aromatic character.

Tunable Solid-State Thermochromism: Alkyl Chain Length-Dependent Conformational Isomerization of Bianthrones.

The introduction of linear alkoxy chains into bianthrone promoted the aggregation of the minor twisted conformer and made it compete with the major folded conformer in the solid-state. Rapid evaporation approach to the methoxy- and n-butoxy-substituted derivatives provided powder mixtures of folded and twisted conformers as metastable solids. Upon heating the powders, different lengths of alkyl chains converged to different conformers via solid-state isomerization reaction with an apparent color change. Monitoring by FT-IR spectroscopy and powder XRD ensured that these isomerization reactions involve only conformational isomerization without pyrolysis. In addition, single crystal X-ray structure analysis revealed that twisted conformers with longer alkyl chains are stabilized in the solid-state by the synergistic effect of their inter-chain hydrophobic interactions and π-π stacking interactions.

Fully conjugated azacorannulene dimer as large diaza[80]fullerene fragment.

A fully conjugated azacorannulene dimer with a large π-surface (76π system) was successfully synthesized from a fully conjugated bifunctional polycyclic aromatic azomethine ylide. This molecule represents an example of diaza[80]fullerene (C78N2) fragment molecule bearing two internal nitrogen atoms. X-ray crystallography analysis shows its boat-shaped structure with two terminal azacorannulenes bent in the same direction. The molecular shape leads to unique selective association with a dumbbell-shaped C60 dimer (C120) over C60 through shape recognition. Owing to its large π-surface and a narrow HOMO-LUMO gap, the azacorannulene dimer exhibits red fluorescence with a quantum yield of up to 31%. The utilization of the fully conjugated bifunctional azomethine ylide is a powerful method for the bottom-up synthesis of large multiazafullerene fragments, providing a step towards the selective total synthesis of multiazafullerenes.

Diazapentabenzocorannulenium: A Hydrophilic/Biophilic Cationic Buckybowl.

Polycyclic aromatic molecules are promising functional materials for a wide range of applications, especially in organic electronics. However, their largely hydrophobic nature has impeded further applications. As such, imparting high solubility/hydrophilicity to polycyclic aromatic molecules leads to a breakthrough in this research field. Herein, we report the synthesis of diazapentabenzocorannulenium, a cationic nitrogen-embedded buckybowl bearing a central imidazolium core, by a bottom-up strategy from polycyclic aromatic azomethine ylide. X-ray crystallography analyses have revealed a bowl-shaped molecular structure that is capable of forming charge-segregated one-dimensional columns by bowl-in-bowl packing. In addition to its fluorescence capabilities and high dispersibility in water, the molecule was found to selectively localize in the mitochondria of various tumor cells, showing potential as viable mitochondria-selective fluorescent probes.

Biradicaloid Behavior of a Twisted Double Bond.

A compound with a highly twisted C═C bond in the intermediate bond dissociation region was isolated, and its biradicaloid nature was experimentally demonstrated. A bianthrone derivative substituted with long-chain alkoxy groups was synthesized, and its twisted conformer was assembled into crystals through hydrophobic intermolecular interactions of the introduced alkoxy chains. X-ray crystallography revealed that the C═C bond connecting the two anthrone rings has a long bond length (1.429 Å) and a large torsional angle (57.33°). In addition, ESR studies revealed that the twisted bianthrone has biradicaloid character with a small singlet-triplet energy gap of 23.8 kJ mol-1. The thermally excited triplet species were observed in the ESR spectrum as distinct fine structures along with a ΔMS = ±2 forbidden transition.

Anatomical evaluation of the femoral attachment of the posterior oblique ligament.

INTRODUCTION: Tibiofemoral joint instability reduces patient satisfaction after total knee arthroplasty (TKA). However, surgeons sometimes encounter excessive medial joint laxity without medial over-release on the tibial side. It was hypothesized that over-resection of the posteromedial femoral condyle can injure the medial stabilizers, especially the posterior oblique ligament (POL) at its femoral attachments. MATERIALS AND METHODS: Thirteen fixed cadaveric knees were exposed, and 3 anatomical points were identified: the posterior edge and midpoint of the POL femoral attachment, and the posterior edge of the superficial medial collateral ligament (sMCL) femoral attachment. The distance from the surface of the posteromedial femoral condyle to each point was measured. Correlations between each point and the anterior-posterior or medial-lateral dimensions of the distal femur were also calculated. RESULTS: The average distances to the posterior edge and midpoint of the POL femoral attachment and the posterior edge of the sMCL femoral attachment were 13.7 mm (9.0-18.4), 17.9 mm (11.5-22.6), and 22.7 mm (14.7-29.4), respectively. There were moderate correlations between the distance to each point and the anterior-posterior or medial-lateral dimensions of the distal femur. CONCLUSIONS: The minimal distance from the surface of the posteromedial condyle to the POL posterior edge was 9.0 mm. Over-resection of the posteromedial femoral condyle, even with a general TKA femoral component, might injure the POL at its femoral attachments, especially in patients with small distal femurs, while the sMCL is rarely damaged. LEVEL OF EVIDENCE: Level IV.

Solvent viscosity-dependent isomerization equilibrium of tetramethoxy-substituted bianthrone.

The designed and synthesized tetramethoxy-substituted bianthrone exists as an equilibrium mixture of the folded and twisted conformers in solution. The introduction of methoxy groups into the 3,3',6,6'-positions of bianthrone reduces the energy difference between the conformers and results in a bistable system. The survey of its equilibrium constant based on the optical absorption and variable temperature quantitative NMR spectroscopic studies in various solvents revealed that the equilibration of the isomerization reaction was found to be most sensitive to solvent viscosity among various solvent parameters. In the statistical thermodynamic approach combined with DFT calculations, the twisted conformations with various torsional angles are populated by thermal fluctuations on the highly anharmonic potential surface, and their ensemble average depends on solvent viscosity because a viscous drag of the solvent controls the degree of fluctuation. Such a statistical population does not occur in the folded conformer because of the harmonic potential surface with respect to the torsional rotation. This difference may result in the solvent viscosity dependence of the isomerization equilibrium constant, that is, the energy difference between the conformers.

The Effects of Well-Rounded Exercise Program on Systemic Biomarkers Related to Cartilage Metabolism.

Nonsurgical treatment such as exercise is the preferred method for management of knee osteoarthritis (OA). A combination of aerobic, muscle strengthening, and flexibility exercises is recommended for older adults. However, effects of the exercise intervention on cartilage metabolism remain unclear. This study used biomarkers to investigate the effects of well-rounded exercise program on cartilage metabolism in 42 women (mean age: 59 years). Participants started a weekly supervised exercise program and continued for 12 weeks. Before and after the program, we measured physical performance on the Timed Up-and-Go Test, 3-Minute Walk Test, and 30-Second Chair Stand Test. We collected serum and urine samples at the start of the program until 24 weeks and measured the concentrations of 4 biomarkers related to type II collagen metabolism: serum cartilage type II procollagen carboxy propeptide (sPIICP), urine C-terminal telopeptide of collagen type II (uCTX-II), urine cleavage of type II collagen by collagenases (uC2C), and serum cartilage oligomeric matrix protein (sCOMP). Participants were divided into pre-OA and OA groups based on X-ray findings. The pre-OA group showed significant increases and decreases in sPIICP and uCTX-II concentrations with improved physical performance, respectively. sCOMP concentrations significantly increased in both groups. The exercise also improved physical performance with no detrimental effect on type II collagen metabolism in the OA group. Thus, well-rounded exercise may not only improve physical capacity but also have beneficial effects on type II collagen metabolism, especially in people without radiological OA.

Quadriceps strength affects patient satisfaction after total knee arthroplasty.

BACKGROUND: Total knee arthroplasty is one of the most successful surgeries with respect to relieving pain and restoring function of the knee. However, some studies have reported that patients are not always satisfied with their results after total knee arthroplasty. The aim of this study was to determine whether the muscle strength around the knee joint and the walking status influence patients' expectations and satisfaction before and after total knee arthroplasty. METHODS: We evaluated 28 patients who underwent 30 primary total knee arthroplasties from March 2012 to June 2013. We assessed patient-reported scores using the 2011 Knee Society Scoring System, knee extensor and flexor strength, the 10-m walking test, and the timed up-and-go test. All assessments were performed preoperatively and 1 year after total knee arthroplasty. We determined the correlation between the patient-reported scores and each variable. RESULTS: Preoperative patient satisfaction was significantly correlated with knee symptoms and functional activities, but not with muscle strength or walking status. Postoperative patient satisfaction was significantly correlated with knee symptoms, functional activities, knee extensor strength, and walking status, including the 10-m walking test and timed up-and-go test, after total knee arthroplasty. In stepwise regression analysis, predictors of patient satisfaction with total knee arthroplasty were knee symptoms, functional ability, and knee extensor strength. CONCLUSIONS: Our study demonstrates that pain relief and restoration of functional activity are highly correlated with increasing patient satisfaction after total knee arthroplasty. The results also indicate that the quadriceps is important for patient satisfaction and restoration of functional activity following total knee arthroplasty.

Serological and Progression Differences of Joint Destruction in the Wrist and the Feet in Rheumatoid Arthritis - A Cross-Sectional Cohort Study.

OBJECTIVE: To investigate clinical and radiological differences between joint destruction in the wrist and the feet in patients with RA. METHODS: A cross-sectional clinical study was conducted in an RA cohort at a single institution. Clinical data included age, sex and duration of disease. Laboratory data included sero-positivity for anti-cyclic citrullinated peptide (CCP) antibody and RF. Radiological measurements included Larsen grades and the modified Sharp/van der Heijde method (SHS) for the hands/wrists and the feet. Statistical analyses were performed using the Kruskal-Wallis H-test, a dummy variable linear regression model and multivariate logistic regression analysis with 95% confidence interval and odds ratios. RESULTS: A total of 405 patients were enrolled, and 314 patients were analysed in this study. The duration of disease in the foot-dominant group was significantly less than that in the wrist-dominant group. When patients were subdivided by duration of disease, the Larsen grade of the feet was significantly higher than that of the wrist in the first quadrant subgroup, but this was reversed with increasing duration of disease. Anti-CCP status was a significant predictive factor for joint destruction in the wrist but not in the feet, while RF status was not predictive in either the wrist or the feet. CONCLUSIONS: Joint destruction in the feet started earlier than in the wrist, but the latter progresses faster with increasing duration of disease. Anti-CCP status predicts joint destruction in the wrist better than in the feet.

Cross-cultural adaptation and validation of the Japanese version of the new Knee Society Scoring System for osteoarthritic knee with total knee arthroplasty.

BACKGROUND: The purposes of this study were to translate the new Knee Society Score (KSS) into Japanese and to evaluate the construct and content validity, test-retest reliability, and internal consistency of the Japanese version of the new KSS. METHODS: The Japanese version of the KSS was developed according to cross-cultural guidelines by using the "translation-back translation" method to ensure content validity. KSS data were then obtained from patients who had undergone total knee arthroplasty (TKA). The psychometric properties evaluated were as follows: for feasibility, response rate, and floor and ceiling effects; for construct validity, internal consistency using Cronbach's alpha, and correlations with quality of life. Construct validity was evaluated by using Spearman's correlation coefficient to quantify the correlation between the KSS and the Japanese version of the Oxford 12-item Knee Score or Short Form 36 Health Survey (SF-36) questionnaires. RESULTS: The Japanese version of the KSS was sent to 93 consecutive osteoarthritic patients who underwent primary TKA in our institution. Fifty-five patients completed the questionnaires and were included in this study. Neither a floor nor ceiling effect was observed. The reliability proved excellent in the majority of domains, with intraclass correlation coefficients of 0.65-0.88. Internal consistency, assessed by Cronbach's alpha, was good to excellent for all domains (0.78-0.94). All of the four domains of the KSS correlated significantly with the Oxford 12-item Knee Score. The activity and satisfaction domains of the KSS correlated significantly with all and the majority of subscales of the SF-36, respectively, whereas symptoms and expectation domains showed significant correlations only with bodily pain and vitality subscales and with the physical function, bodily pain, and vitality subscales, respectively. CONCLUSIONS: The Japanese version of the new KSS is a valid, reliable, and responsive instrument to capture subjective aspects of the functional symptoms and abilities of patients who undergo TKA.

Delayed wound healing after forefoot surgery in patients with rheumatoid arthritis.

OBJECTIVE: To elucidate the systemic and local risk factors and the effect of surgical procedures for delayed wound healing after forefoot surgery in patients with rheumatoid arthritis (RA). METHODS: Fifty forefoot surgeries were performed in 39 patients using resection arthroplasty or a joint-preserving procedure (25 feet for each procedure). The associations between the occurrence of delayed wound healing and clinical variables, radiological assessment, or surgical procedures were analyzed. RESULTS: Delayed wound healing was recorded in nine feet of eight patients. The duration of RA was significantly longer in the delayed healing group than that in the healed group. Age, sex, smoking history, concomitant diabetes, and RA medication did not differ between the groups. Radiological evaluation showed significant differences between groups in metatarsophalangeal dorsal flexion angle. The shortened length of the fourth and the fifth metatarsal bones affected the occurrence of the complication. The joint-preserving procedure had significantly less delayed wound healing compared with resection arthroplasty. CONCLUSIONS: Preoperative dorsoplantar deformity and perioperative tissue damage can cause delayed wound healing after forefoot surgery in RA patients.