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The development in the crystal structure analysis of synthetic polymers using the hybridized combination of wide-angle X-ray and neutron diffraction (WAXD and WAND, respectively) techniques has been reviewed with many case studies performed by the authors. At first, the technical development was reviewed, in which the usage of high-energy synchrotron X-ray source was emphasized for increasing the total number of the observable diffraction peaks, and several examples were introduced. Secondly, the usage of the WAND method was introduced, in which the successful extraction of hydrogen atomic positions was described. The third example is to show the importance for the hybrid combination of these two diffraction methods. The quantitative WAXD data analysis gave the crystal structures of at-poly(vinyl alcohol) (at-PVA) and at-PVA-iodine complex. However, the thus-proposed structure models were found not to reproduce the observed WAND data very much. The reason came from the remarkable difference in the atomic scattering powers of the constituting atomic species between WAXD and WAND phenomena. The introduction of statistical disorder solved this serious problem, which reproduced both of the observed WAXD and WAND data consistently. The more systematic combination of WAXD and WAND methods, or the so-called X-N method, was applied also to the quantitative evaluation of the bonded electron density distribution along the skeletal chains, where the results about polydiacetylene single crystals were presented as the first successful study. Finally, the application of WAND technique in the trace of structural changes induced under the application of external stress or temperature was described. The future perspective is described for the development of structural science of synthetic polymers on the basis of the combined WAXD/WAND techniques. [ABSTRACT FROM AUTHOR]

Despite recent advances in bonding restorations, which are the basis of restorative dentistry, secondary caries are still able to form. Previously, a novel fluoride-containing zinc and copper (ZCF) nanocomposite was introduced to prevent the formation of caries due to its antibacterial activity. In this study, we studied the impact of ZCF nanoparticles on the adhesive strength of bonding restorations through micro-tensile bond strength (µTBS) testing. The impact of antibacterial and matrix metalloproteinase (MMP) inhibitors on the nanoparticles was also examined. The nanocomposites were prepared using a simple one-step homogeneous co-precipitation method at a low temperature. A self-etch adhesive was applied to 10 extracted caries-free human molars with (test group) and without (control group) the ZCF nanoparticles. This was followed by composite resin build-up and µTBS testing, MMP activity assays, and evaluation of the antibacterial effects. The results showed no significant differences in the µTBS between the ZCF and the control groups. However, the ZCF exhibited a significant inhibitory effect against MMP-2, MMP-8, and MMP-9, in addition to an antibacterial effect on Streptococcus mutans. Therefore, the present study demonstrated that the addition of ZCF nanoparticles to adhesive systems can result in MMP inhibition and antibacterial action while maintaining the mechanical properties of the bonding restorations. [ABSTRACT FROM AUTHOR]

Introduction: Chronic limb-threatening ischemia (CLTI) is a clinical syndrome defined by peripheral arterial disease (PAD) combined with rest pain, gangrene, or leg ulceration for longer than two weeks resulting in lower extremity amputation. In recent years, low-density lipoprotein apheresis (LDL-A) has been implemented for PAD treatment. However, it has not been possible to ensure insurance coverage for patients with lower LDL levels than 140 mg/dL under cholesterol-lowering drugs. Rheocarna is a novel adsorption-type blood purification device for the treatment of CLTI by adsorbing LDL and fibrinogen (Fib) that is not constrained by hypercholesterolemia and is not amenable to or nonresponsive to revascularization surgery. The only requirements for use are that the blood flow rate increases up to 200 mL/min gradually., Methods: To evaluate the applicability of this treatment procedure, we compared the removal rates of Fib and LDL following Rheocarna therapy using various blood treatment volumes (6, 10.5, and 19.5 L)., Results: Fib and LDL removal rates were about 20% and 15%-25% per treatment, with no significant differences between treatment volumes. Following treatment with Rheocarna, blood pressure tends to decrease at first, which later increases, and the higher the treatment volume, the longer the time of low blood pressure tended to be., Conclusion: Although no significant difference was found in the removal rate of Fib and LDL in response to increase volume to 6 L or beyond in this study, the 6 L volume is considered effective enough for the removal of Fib and LDL., (© 2023 International Society for Apheresis and Japanese Society for Apheresis.)

Background: Immunoglobulin A vasculitis is a systemic form of vasculitis that predominantly affects children. Factor XIII activity is decreased in some cases, and several reports have shown an association between abdominal pain and decreased factor XIII activity. However, the clinical significance of decreased factor XIII activity in pediatric immunoglobulin A vasculitis has not been fully elucidated. This study aimed to identify the association between factor XIII activity and the clinical course of pediatric patients with immunoglobulin A vasculitis., Methods: Forty-four pediatric patients, admitted to Kita-Harima Medical Center with a clinical diagnosis of immunoglobulin A vasculitis between October 1, 2013 and September 30, 2022, were retrospectively reviewed, and 22 patients were analyzed. The patients' background characteristics and clinical course were compared between the normal and decreased factor XIII activity (<70%) groups., Results: The group with decreased factor XIII activity showed a significantly increased duration of hospitalization (14 [6-36] vs. 7 [5-13] days, p = 0.01), total glucocorticoid dose (prednisolone 22.7 [4.9-55.5] vs. 10.1 [3.4-19.6] mg/kg, p = 0.02), and duration of glucocorticoid administration (19 [4-85] vs. 10 [3-15] days, p = 0.03). Correlational analyses showed that these three parameters were negatively correlated with factor XIII activity., Conclusions: Factor XIII activity was negatively correlated with the duration of hospitalization, total glucocorticoid dose, and duration of glucocorticoid administration. Factor XIII activity is not only associated with abdominal symptoms but also may be a marker to predict the overall trajectory of acute-phase treatment in pediatric patients with immunoglobulin A vasculitis.

This study evaluated the effect of tricalcium phosphate-containing fluoride varnish on the prevention of root caries using an in-air micro-proton induced X-ray/gamma-ray emission system and microcomputed tomography. Either fluoride varnish (FV) or tricalcium phosphate-containing fluoride varnish (WV) was applied to root dentin, whereas dentin without varnish were considered controls. After immersion in saline, dentin sections were prepared, and concentration of fluoride ion was measured. These specimens were demineralized, and the mineral loss was measured. Caries inhibition in sound and demineralized dentin was observed in both FV and WV groups compared to the control group. Significantly low mineral loss was found especially in the demineralized dentin, which is probably due to the combination effect of calcium and fluoride ions at a concentration range of 100,000 ppm, as supplied by the varnish. The use of calcium-containing fluoride varnish, especially in demineralized dentin, is effective in arresting initial dentin caries.

This study aimed to use an in-air micro-particle-induced X-ray/gamma emission (in-air µPIXE/PIGE) system to evaluate tooth-bound fluoride (T-F) in dentin following the application of fluoride-containing tooth-coating materials. Three fluoride-containing coating materials (PRG Barrier Coat, Clinpro XT varnish, and Fuji IX EXTRA) and a control were applied to the root dentin surface of human molars (n = 6, total 48 samples). Samples were stored in a remineralizing solution (pH 7.0) for 7 or 28 days and then sectioned into two adjacent slices. One slice of each sample was immersed in 1M potassium hydroxide (KOH) solution for 24 h and rinsed with water for 5 min for the T-F analysis. The other slice did not undergo KOH treatment and was used to analyze the total fluoride content (W-F). The fluoride and calcium distributions were measured in all the slices using an in-air µPIXE/PIGE. Additionally, the amount of fluoride released from each material was measured. Clinpro XT varnish demonstrated the highest fluoride release among all the materials and tended to show high W-F and T-F and lower T-F/W-F ratios. Our study demonstrates that a high fluoride-releasing material shows high fluoride distribution into the tooth structure and low conversion from fluoride uptake by tooth-bound fluoride.

Several desensitizers routinely used clinically for dentin hypersensitivity are expected to inhibit demineralization. This study aimed to evaluate the effectiveness of sealing materials in inhibiting demineralization and increasing fluorine (F) uptake by acid-treated root surfaces. Five noncarious extracted human teeth were used to produce specimens. Three different fluoride-containing materials, namely "MS Coat F" (MS), "MS Coat Hys Block Gel" (HS), and CTX2 Varnish (FV), were used herein. Each material was applied to the demineralized root surface. Single sections were obtained from each specimen. All surfaces of each specimen, except the polished surface, were covered with wax and immersed in an automatic pH cycling system for 2 weeks. Fluorine and calcium distributions in the carious lesions of each specimen were evaluated using proton-induced gamma emission (PIGE) and X-ray (PIXE) techniques, respectively. Dentin demineralization was analyzed using transverse microradiography (TMR) before and after pH cycling. µPIXE/PIGE analysis demonstrated that all sample groups showed increased fluoride uptake on the root surface. TMR analysis revealed that both HS and FV showed significantly lower integrated mineral loss values than the control group. All three samples demonstrated a tendency towards increased fluoride uptake from fluoride-containing hypersensitivity desensitizers and a demineralization inhibition effect on root dentin.

This study employed an in-air micro-proton-induced X-ray/gamma-ray emission system to assess the effectiveness of fluoride-containing materials (FCMs) incorporating calcium in preventing root caries. Dentin surfaces of human third molars were coated with one of three FCMs: fluoride-releasing glass-ionomer cement (F7) and experimental materials in which half (P1) or all (P2) of the strontium in F7 was replaced with calcium. Dentin without FCM coating served as the control. Specimens were immersed in saline at 37°C for 1 month, sectioned, and then demineralized. Calcium loss after demineralization was lower in the Ca-substituted groups than in the Ca-unsubstituted groups (p<0.05). Calcium loss was negatively correlated with fluoride uptake (p<0.01). In the F7, P1, and P2 groups, the retraction of the dentin surface was significantly suppressed as compared with the control group. FCMs incorporating calcium improved the acid resistance of root dentin and could help prevent root caries.

Plasma volume (PV) variation during therapeutic apheresis (TA) (such as plasma exchange [PE] and selective PE using albumin solution as replacement solution or immunoadsorption plasmapheresis) has been considered to be unignorable. It changes the concentration of the target molecule and might impact its removal rate (RR.) This study aimed to evaluate the effects of PV variation on the calculation of the RR of fibrinogen and immunoglobulin by categorizing the hematocrit (Ht) change during TA into two patterns, that is, increased group and decreased group. In all modalities of TA, the Ht level frequently changed during apheresis sessions. In calculating RR, RR calculated with Ht adjustment was significantly higher than that calculated without adjustment in the increased group and significantly lower than it in the decreased group. Therefore, RR might have been underestimated in the increased group and overestimated in the decreased group when RR was calculated without Ht adjustment. Ht adjustment is suggested to be crucial in calculating RR in TA., (© 2021 International Society for Apheresis, Japanese Society for Apheresis, and Japanese Society for Dialysis Therapy.)