Proposals for talonavicular joint assessment using ultrasound imaging and its reliability and validity.

[Purpose] We aimed to develop a noninvasive specific ultrasonographic assessment of the talonavicular joint during loading to facilitate the analysis of treatment of flatfoot. [Participants and Methods] Sixty healthy participants underwent ultrasound imaging of the talonavicular joint while sitting and standing. The talonavicular angle was defined as the intersection of the line connecting the navicular and talar heads and the line connecting the talar head and sustentaculum tali. Talonavicular coverage was assessed using X-ray images of 15 participants. [Results] Ultrasonographic assessment of the talonavicular joint showed a lateral shift of the navicular relative to the head of the talus from sitting to standing. The talonavicular angle was significantly larger when standing than in the sitting position. The difference in talonavicular angle values between sitting and standing significantly correlated with the differences in the talonavicular coverage values. [Conclusion] We showed that ultrasonographic talonavicular angle assessment has good reliability and moderate validity for detecting significant alignment changes in the talonavicular joints due to loading. In the future, this evaluation method should be performed before and after exercise therapy to assess and develop appropriate exercise therapy for flatfoot.

In vivo interrelationships between the gluteus minimus and hip joint capsule in the hip internal rotation position with flexion.

BACKGROUND: The flexion adduction internal rotation (FADIR) test is performed by the combined motions of hip flexion (with knee flexion), adduction, and internal rotation, and can often reproduce anterior hip pain consistent with an individual's presenting pain. Since it has high sensitivity for intraarticular pathology diagnosis but low specificity, understanding the extraarticular pathology that can induce anterior hip pain in the FADIR test may also be essential. This study hypothesized that the interrelationships between the joint capsule and gluteus minimus differ in individuals with and without FADIR-positive pain and aimed to elucidate the in vivo interrelationships at hip internal rotation in 90°-flexion, which is also often restricted in individuals with FADIR-positive pain. METHODS: Ten hips were included in the FADIR-positive group, and ten hips without hip pain in the FADIR test were included in a control group. Based on the ultrasound images at the four hip rotation conditions (20° and 10° external rotations, 0° external/internal rotation, and 10° internal rotation), orientation measurements of the gluteus minimus (muscle belly portion) and joint capsule were performed and quantitatively compared between the FADIR-positive and control groups. Additionally, 3 hips of 3 participants were randomly selected from each of the control and FADIR-positive groups for magnetic resonance imaging analysis. RESULTS: At 0°-external/internal and 10°-internal rotation, on ultrasound images, fibers of the gluteus minimus and joint capsule in the FADIR-positive group were significantly more oriented in the same direction than those in the control group. Magnetic resonance imaging showed that the loose connective tissue between the gluteus minimus and joint capsule was prominent at 10°-internal rotation in the control group, although this was not apparent in the FADIR-positive group. CONCLUSIONS: At hip internal rotation in 90° flexion, the muscular belly portion of the gluteus minimus and joint capsule were oriented in the same direction to a greater extent in the FADIR-positive group than in the control group owing to a morphological change in the loose connective tissue between them. The pathological changes in the loose connective tissue may inhibit smooth movement of the gluteus minimus relative to the joint capsule in individuals with FADIR-positive pain.

Tetraphenylethene Derivatives Bearing Alkylammonium Substituents: Synthesis, Chemical Properties, and Application as BSA, Telomere DNA, and Hydroxyl Radical Sensors.

Tetraphenylethene derivatives (TPEs) are used as luminescence probes for the detection of metal ions and biomolecules. These sensors function by monitoring the increase in the photoluminescence (PL) intensity of the TPEs resulting from aggregation-induced emission (AIE) upon interaction with the analytes. The AIE behavior of the sensors was investigated by measuring their PL. In this study, PL, PL lifetime, and confocal laser scanning microscopy measurements were carried out as part of our in-depth investigation of AIE behavior of TPEs for the detection of biomolecules and radical species. We used 1,1,2,2-tetrakis(4-((trimethylammonium)alkoxy)phenyl)tetraphenylethene tetrabromide (TPE-C(m)N+Me3Br-, m = 2, 4, and 6, where m denotes the number of methylene groups in the alkyl chain) and TPE-C(m)N+Me3TCNQ-• (TCNQ-• is the 7,7',8,8'-tetracyanoquinodimethane anion radical) as luminescent probes for the detection of bovine serum albumin (BSA), DNA, and the hydroxyl radical (•OH) generated from Fenton's reagent. The sensing performance of TPE-C(m)N+Me3Br- for BSA and DNA was found to depend on the length of the alkyl chains (m). UV-vis and PL measurements revealed that the responses of TPE-C(m)N+Me3Br- and TPE-C(4)N+TCNQ-• to Fenton's reagent depended on the solvent. The electrochemical properties of the TPE derivatives prepared in this study were additionally investigated via cyclic voltammetry.

Automatic Identification of Ultrasound Images of the Tibial Nerve in Different Ankle Positions Using Deep Learning.

Peripheral nerve tension is known to be related to the pathophysiology of neuropathy; however, assessing this tension is difficult in a clinical setting. In this study, we aimed to develop a deep learning algorithm for the automatic assessment of tibial nerve tension using B-mode ultrasound imaging. To develop the algorithm, we used 204 ultrasound images of the tibial nerve in three positions: the maximum dorsiflexion position and -10° and -20° plantar flexion from maximum dorsiflexion. The images were taken of 68 healthy volunteers who did not have any abnormalities in the lower limbs at the time of testing. The tibial nerve was manually segmented in all images, and 163 cases were automatically extracted as the training dataset using U-Net. Additionally, convolutional neural network (CNN)-based classification was performed to determine each ankle position. The automatic classification was validated using five-fold cross-validation from the testing data composed of 41 data points. The highest mean accuracy (0.92) was achieved using manual segmentation. The mean accuracy of the full auto-classification of the tibial nerve at each ankle position was more than 0.77 using five-fold cross-validation. Thus, the tension of the tibial nerve can be accurately assessed with different dorsiflexion angles using an ultrasound imaging analysis with U-Net and a CNN.

In vivo magnetic resonance imaging study of the hip joint capsule in the flexion abduction external rotation position.

Although the flexion abduction external rotation (FABER) test is a useful hip provocation test, hip soft tissue characteristics in the FABER position remain unclear. This study investigated the in-vivo joint capsule characteristics, including its articular cavity area and relation to the fat pad surrounded by the joint capsule and pericapsular muscles, in the FABER position using magnetic resonance imaging. Thirteen hips from 13 healthy volunteers were analyzed. The images were obtained, with the participant hips at 15°-extension, 45°-flexion, and in the FABER position, to analyze the articular cavity size and fat pad and calculate these ratios to size of the femoral neck. The articular cavity area and its ratio to the femoral neck were significantly greatest in the FABER position, followed by those in the hip flexion and extension. Additionally, the area of the fat pad in the inter-pericapsular muscle space and its ratio to the femoral neck in the FABER position were significantly larger than those in the hip flexion and, as a tendency, larger than those in hip extension. To the best of our knowledge, this is the first in-vivo study to show the interrelationship among the joint capsule, pericapsular muscles, and fat pad in the FABER position.

[A New Method for Calculating Iodine Dose in Abdominal Dynamic Contrast-enhanced Computed Tomography: Calculation Based on Patients' Body Size Parameters and Estimated Volume of Distribution of Non-ionic Contrast Medium].

PURPOSE: This study aimed at analyzing the relationship between the estimated volume of distribution on computed tomography (eVdCT) of non-ionic contrast medium and four different patients' body size parameters (BSPs) (total body weight, body mass index, body surface area, and lean body weight) in abdominal dynamic contrast-enhanced computed tomography (ADCE-CT) . Moreover, this study intended to derive a method for calculating the iodine dose to target contrast enhancement. METHODS: We measured enhanced CT values of the equilibrium phase of the abdominal aorta in 527 patients who underwent ADCE-CT. The eVdCT of the ADCE-CT equilibrium phase was calculated from enhanced CT values based on the pharmacokinetic model. The optimal iodine dose (OID) was calculated from the regression analysis of eVdCT and BSP. RESULTS: The eVdCT was 7741.1±1799.5 ml. The eVdCT showed a strong positive correlation with BSP and could be calculated using a linear regression equation. The correlation coefficients for total body weight, body surface area, and lean body weight were 0.83, 0.84, and 0.81, respectively. The OID per unit BSP required for target iodine concentration of the abdominal aorta on ADCE-CT (TIC) could be calculated as "OID [mgI/BSP]=[(aï½¥BSP+b)×TIC]/BSP". CONCLUSION: The OID calculation method based on the patients' body size parameters and estimated volume of distribution can normalize contrast enhancement in abdominal dynamic contrast-enhanced CT.

Water-soluble oligofluorenes bearing N1-alkylcytosine side chains as turn-on and turn-off materials in telomere DNA length sensing.

Water-soluble cationic and anionic oligofluorenes bearing N1-alkylcytosine side chains, namely OF-1 and OF-2, were synthesized. The photoluminescence (PL) intensity of an aqueous solution of OF-1 decreased on the addition of (TTAGGG)m as telomere DNA models. In contrast, the PL intensity of OF-2 increased on the addition of DNA.

Eco-friendly synthesis of ionic helical polymers and their chemical properties and reactivity.

Reaction of N-(2,4-dinitrophenyl)pyridinium chloride (salt(Cl-)) with sodium dicyanamide (Na(CN)2N) resulted in anion exchange between Cl- and (CN)2N- to yield a new Zincke salt, salt((CN)2N-). Reactions of salt((CN)2N-) with piperazine, specifically (R)-(-)- or (S)-(+)-2-methylpiperazine under eco-friendly conditions, such as in aqueous solution, in the absence of a catalyst, and at room temperature, resulted in pyridinium ring opening to yield ionic high-molecular-weight polymers with 5-2,4-dienylideneammonium dicyanamide units or chiral 5-(2-methylpiperazinium)-2,4-dienylideneammonium dicyanamide units, namely, polymer(H;(CN)2N-), polymer(R-Me;(CN)2N-), and polymer(S-Me;(CN)2N-). UV-Vis measurements revealed that the π-conjugation system expanded along the polymer chain due to the orbital interaction between the electrons on the two nitrogen atoms of the piperazinium ring. Circular dichroism (CD) measurements revealed a helical conformation of the main chain in polymer(R-Me;(CN)2N-) and polymer(S-Me;(CN)2N-). The reaction of polymer(H;(CN)2N-) with p-phenylenediamine (PDA) caused recyclization of the 2,4-dienylideneammonium unit and resulted in depolymerization to yield N-(4-aminophenyl)pyridinium dicyanamide. Cyclic voltammetry analysis suggested that the polymers obtained in this study undergo electrochemical oxidation and reduction.

Fat-subtracted three-dimensional time-of-flight MR angiography of the neck by use of fat-only images with the two-point Dixon technique.

For improvement of three-dimensional time-of-flight magnetic resonance angiography (3D-TOF-MRA) image quality in the neck, fat-subtracted MRA by use of the two-point Dixon technique was compared with conventional fat-suppressed MRA techniques. Three different types of neck 3D-TOF-MRA were obtained [minimum echo time (TE) (1.9 ms), opposed-phase TE (3.4 ms), and chemical shift selective fat suppression (CHESS) (TE = 1.9 ms)] on five volunteers at 3.0 T. MRA was obtained with subtraction of fat-only images (produced by a two-point Dixon sequence) from minimum-TE MRA images, and compared with other fat-suppressed MRA images. Fat-subtracted MRA demonstrated uniform fat suppression compared with other techniques. The mean vessel-to-fat contrast in fat-subtracted MRA was significantly higher (p < 0.01) than in other MRA images (minimum-TE: 0.137 ± 0.086, opposed-phase TE: 0.268 ± 0.102, CHESS: 0.307 ± 0.052, fat-subtracted: 0.965 ± 0.101). The mean vessel-to-muscle contrast in opposed-phase TE MRA was significantly lower (p < 0.01) than in other MRA images (minimum-TE: 0.526 ± 0.036, opposed-phase TE: 0.419 ± 0.188, CHESS: 0.511 ± 0.023, fat-subtracted: 0.573 ± 0.016). Fat-subtracted MRA by use of the two-point Dixon technique improves the image quality of neck MRA. This technique would be a useful method for MRA, especially in areas with inhomogeneous magnetic fields, such as the neck.

[Measurement of slice thickness in magnetic resonance image by the impulse response].

The purpose of this study was to verify the applicability of measurement of slice thickness of magnetic resonance imaging (MRI) by the delta method, and to discuss the measurement precision by the disk diameter and baseline setup of the slice profile of the delta method. The delta method used the phantom which put in the disk made of acrylic plastic. The delta method measured the full width at half maximum (FWHM) and the full width at tenth maximum (FWTM) from the slice profile of the disk signal. Evaluation of the measurement precision of the delta method by the disk diameter and baseline setup were verified by comparison of the FWHM and FWTM. In addition, evaluation of the applicability of the delta method was verified by comparison of the FWHM and FWTM using the wedge method. The baseline setup had the proper signal intensity of an average of 10 slices in the disk images. There were statistically significant difference in the FWHM between disk diameter of 10 mm and disk diameter of 30 mm and 5 mm. The FWHM of the disk diameter of 10 mm was smaller than the disk diameter of 30 mm and 5 mm. There was no statistically significant difference in the FWHM between the delta method and the wedge method. There is no difference in the effective slice thickness of the delta method and the wedge method. The delta method has an advantage in measurement of thin slice thickness.

MR perfusion imaging by alternate slab width inversion recovery arterial spin labeling (AIRASL): a technique with higher signal-to-noise ratio at 3.0 T.

OBJECT: To propose a new arterial spin labeling (ASL) perfusion-imaging method (alternate slab width inversion recovery ASL: AIRASL) that takes advantage of the qualities of 3.0 T. MATERIALS AND METHODS: AIRASL utilizes alternate slab width IR pulses for labeling blood to obtain a higher signal-to-noise ratio (SNR). Numerical simulations were used to evaluate perfusion signals. In vivo studies were performed to show the feasibility of AIRASL on five healthy subjects. We performed a statistical analysis of the differences in perfusion SNR measurements between flow-sensitive alternating inversion recovery (FAIR) and AIRASL. RESULTS: In signal simulation, the signal obtained by AIRASL at 3.0 and 1.5 T was 1.14 and 0.85%, respectively, whereas the signal obtained by FAIR at 3.0 and 1.5 T was 0.57 and 0.47%, respectively. In an in vivo study, the SNR of FAIR (3.0 T) and FAIR (1.5 T) were 1.73 ± 0.49 and 1.02 ± 0.20, respectively, whereas the SNRs of AIRASL (3.0 T) and AIRASL (1.5 T) were 3.93 ± 1.65 and 1.34 ± 0.31, respectively. SNR in AIRASL at 3.0 T was significantly greater than that in FAIR at 3.0 T. CONCLUSION: The most significant potential advantage of AIRASL is its high SNR, which takes advantage of the qualities of 3.0 T. This sequence can be easily applied in the clinical setting and will enable ASL to become more relevant for clinical application.

Optimizing scan timing of hepatic arterial phase by physiologic pharmacokinetic analysis in bolus-tracking technique by multi-detector row computed tomography.

Our aim in this study was to determine an optimal delay time of hepatic arterial phase (HAP) imaging of hypervascular hepatocellular carcinomas (HCCs) in dynamic contrast-enhanced MDCT (DCE-CT) by use of the bolus-tracking method. The time-enhancement curves (TECs) of the aorta and the contrast of the hepatic arterial and portal system (APC) in the pharmacokinetic analysis were calculated. The clinical study included 41 patients with known or suspected HCC who underwent DCE-CT. The TECs of the aorta and the tumor-liver contrast (TLC) in the clinical study were calculated. On pharmacokinetic analysis, the peak aortic enhancement and the peak APC simulated under conditions of an injection duration of 30 s and an iodine load of 500 mg I/kg body weight were observed 18.5 and 22.5 s, respectively, after the trigger threshold (increased CT value 100 Hounsfield units), respectively. In the clinical study, the peak aortic enhancement and the peak TLC were observed 17.2 and 24.8 s after the trigger threshold, respectively. The optimal delay times until peak aortic enhancement and peak HAP were 15-17 and 19-21 s after the trigger threshold, respectively, under the following conditions: injection dose, 500 mg I/kg body weight; injection duration, 30 s; acquisition time, 5 s; and the trigger threshold. In addition, the peak TLC was achieved 4-7 s after the time to peak aortic enhancement.

[Development of a linear stage compatible for magnetic resonance imaging systems].

A magnetic resonance imaging (MRI) system compatible linear stage was developed. The stage was made of acrylic plastic and moving power was applied by an ultrasonic motor. Moving distance of the stage was detected by counting the number of motor rotations using a optic fiber sensor. Accuracy and precision of the stage control were measured inside and outside the magnet using a micrometer and a laser distance meter. As a result, a value of more than 95% was achieved in both of them in the 1.5 T magnetic field when it was applied for more than a 0.3 mm movement. Measurement of the slice sensitivity profile (SSP) by the delta method was performed. Slice selection by this linear stage and by radio frequency (RF) offset were compared. The result by linear stage was in good agreement with the result by RF offset. With this linear stage, a performance evaluation test of MRI equipments that need micromotion can be performed.

[Fully automated immunoassay system utilizing microchip electrophoresis].

Application of microTAS (micro Total Analysis Systems) technologies utilizing chips with microfluidic channels to clinical diagnostic testing has drawn a lot of attention since it is expected to contribute to shortening reaction time, reduction of reagent/sample consumption, reducing instrument size, and other advantages of microchip electrophoresis. We have developed a fully automated immunoassay system by employing isotachophoresis followed by capillary gel electrophoresis for immunoreaction and B/F separation in microfluidic channels on polymer microchips. Laser-Induced Fluorescence (LIF) was used for detection of the sandwich immunocomplex composed of DNA-conjugate antibody, antigen and fluorescent dye-conjugated antibody. An immunoassay for PIVKA II was demonstrated on this new microTAS system utilizing the DNA-conjugated anti PIVKA II antibody and the fluorescent-dye labeled anti-prothrombin antibody. The resulting assay showed good assay performance with high sensitivity (LOD = 5mAU/mL), good reproducibility(CV = 1.0 - 5.7%) and good correlation with the commercially available PIVKA II assay kit (regression curve of y = 1.04x + 11.1, r = 0.991). The assay turn around time (TAT) was about 9 min. The PIVKA II assay will be useful for the diagnosis and prognosis of hepatocellular carcinoma.

Removal of fluoride ion by bone char produced from animal biomass.

Bone char (BC) was prepared by carbonizing four types of animal biomass, and the adsorption of fluoride ions and elution of phosphate ions were investigated. It was found that the BC yield decreased as carbonization temperature increased, and that carbonization temperature had no significant effect on surface pH, base or acid consumptions. Fluoride ion adsorption was increased in BC produced at a low carbonization temperature. The adsorption mechanism of fluoride ion on BCs might be monolayer adsorption. BC can potentially be used to remove fluoride ions in drinking water. However, it was found that phosphate ions from BC are eluted due to adsorption of fluoride ions, and that ingestion of large amounts of phosphate ions inhibits reabsorption of calcium in the human body. Thus there is a need to study the elution behavior of phosphate ions. The adsorption mechanisms of fluoride ions onto BC would be a physical adsorption onto BC and phosphate ion in BC is exchanged to fluoride ion.

Degradation characteristics of 17beta-estradiol by ozone treatment with activated carbon.

The present study investigates (1) ozone treatment, (2) adsorption treatment using activated carbon treatment, and (3) ozone treatment with activated carbon for their efficacy in removing 17beta-estradiol (E2) present in an aqueous solution. Both ozone and activated carbon treatments for 20 min were effective in removing E2 (initial concentration, 100 mg/L). However, both treatments have been used for two processes, and the disposal time with these treatments is more than that of another treatment. In this study, ozone treatment with activated carbon was investigated with regard to the percentage of E2 removal, pH, and chemical oxygen demand (COD). The physical and chemical characteristics of the activated carbon surface were modified due to the ozone treatment: the surface was oxidized by ozone. The surface of activated carbon exhibited polarity groups and became porous after ozone treatment. The amount of E2 adsorbed onto the ozone-treated activated carbon surface was similar to that adsorbed onto the untreated activated carbon surface. The percentage of E2 removal by ozone treatment with activated carbon was greater than that by ozone treatment alone. Moreover, the rate of E2 removal by ozone treatment with activated carbon was higher than that by ozone or activated carbon treatments alone. Ozone with activated carbon treatment may be used for the removal of E2. However, this ozone treatment for the degradation of E2 may have a greater COD than that in the case of activated carbon treatment alone.

Automated immunoassay system for AFP-L3% using on-chip electrokinetic reaction and separation by affinity electrophoresis.

Implementation of the on-chip immunoassay for alpha-fetoprotein (AFP)-L3% was achieved using a fully automated microfluidic instrument platform that will prepare the chip and run the assay with a total assay time of less than 10min. Reagent/sample mixing, concentration, and reaction in microfluidic channels occur by the electrokinetic analyte transport assay (EATA) technique, enabling the integration of all assay steps on-chip. The determination of AFP-L3%, a biomarker for hepatocellular carcinoma, was achieved by the presence of Lens culinaris agglutinin in the separation channel, causing separation of the fucosylated isoform, AFP-L3, from the nonfucosylated AFP-L1 by lectin affinity electrophoresis. Laser-induced-fluorescence (LIF) detection was used to quantitate the labeled immunocomplexes. The limit of detection (LOD) was 0.1ng/ml AFP, and assay precision of less than 2% coefficient of variation (CV) was obtained for quantitation from 24 to 922ng/ml total AFP in spiked serum samples. Assay precision of less than 3% CV was obtained for AFP-L3% measurements from 8.5 to 81%. Furthermore, good correlation of test results for 68 patient serum samples with a commercially available reference method (LiBASys assay for AFP-L3%) was obtained, with r(2)=0.981 and slope=1.03.

Evaluation of required saline volume in dynamic contrast-enhanced computed tomography using saline flush technique.

The present study was performed to find the required volume of physiological saline for flushing that will allow the most efficient use of contrast medium during the early phase of dynamic CT. We calculated contrast medium aortic arrival time (AT), time to peak aortic enhancement (TPAE) and the elapsed time to TPAE from AT (rise time) from the TECs of pharmacokinetic analysis and clinical study. The rise time determined in the clinical study was 6.2s, which was shorter than that in the simulation study. In the present study, an appropriate volume for saline flush was estimated to be about 18 ml.