Changes in the excitability of anterior horn cells in a mental rotation task of body parts

INTRODUCTION/AIMS

Mental rotation (MR), a tool of implicit motor imagery, is the ability to rotate mental representations of two- or three-dimensional objects. Although many reports have described changes in brain activity during MR tasks, it is not clear whether the excitability of anterior horn cells in the spinal cord can be changed. In this study, we examined whether MR tasks of hand images affect the excitability of anterior horn cells using F-wave analysis.

METHODS

Right-handed, healthy participants were recruited for this study. F-waves of the right abductor pollicis brevis were recorded after stimulation of the right median nerve at rest, during a non-MR task, and during an MR task. The F-wave persistence and the F/M amplitude ratio were calculated and analyzed.

RESULTS

Twenty participants (11 men and 9 women; mean age, 29.2 ± 4.4 years) were initially recruited, and data from the 18 that met the inclusion criteria were analyzed. The F-wave persistence was significantly higher in the MR task than in the resting condition (p = .001) or the non-MR task (p = .012). The F/M amplitude ratio was significantly higher in the MR task than in the resting condition (p = .019).

DISCUSSION

The MR task increases the excitability of anterior horn cells corresponding to the same body part. MR tasks may have the potential for improving motor function in patients with reduced excitability of the anterior horn cells, although this methodology must be further verified in a clinical setting.

Immediate Reduction in Spasticity of Ankle Plantar Flexors in a Stroke Patient after Treatment with a Spinning Permanent Magnet Device

Background

Magnetic stimulation devices can be large because of the need for cooling systems. We developed a compact and lightweight Spinning Permanent Magnet (SPM) device that generates magnetic fields with intensities below the motor threshold. In this report, we present the case of a post-stroke patient in which an immediate reduction in spasticity of the ankle plantar flexors was achieved after SPM treatment.

Case

A 37-year-old man was admitted to our hospital with a right putamen hemorrhage. The patient underwent conservative therapy and exhibited residual left hemiplegia and spasticity. Three months after stroke onset, he was able to walk with supervision while using a left ankle-foot orthosis and a T-cane. The Modified Ashworth Scale (MAS) score of the left ankle plantar flexors was 1+. The plantar flexors were stimulated by SPM treatment. The outcomes were the Hmax/Mmax of the tibial nerve (soleus muscle) and the MAS score. On the first day, SPM stimulation was applied for 30 min. On the second day, a sham stimulation of the same duration was performed. On the third day, the SPM stimulation was repeated. Hmax/Mmax decreased from 41.5% to 37.7% on the first day, and from 46.9% to 31.6% on the third day after SPM stimulation. The MAS score decreased from 1+ to 1 on both days. In contrast, after sham stimulation, Hmax/Mmax increased from 39.2% to 44.2%, whereas the MAS score remained unchanged at 1+.

Discussion

Stimulation below the motor threshold using SPM treatment can effectively reduce spasticity.

β-hydroxybutyrate is a metabolic regulator of proteostasis in the aged and Alzheimer disease brain

Loss of proteostasis is a hallmark of aging and Alzheimer disease (AD). Here, we identify β-hydroxybutyrate (βHB), a ketone body, as a regulator of protein solubility in the aging brain. βHB is a small molecule metabolite which primarily provides an oxidative substrate for ATP during hypoglycemic conditions, and also regulates other cellular processes through covalent and noncovalent protein interactions. We demonstrate βHB-induced protein insolubility across in vitro, ex vivo, and in vivo mouse systems. This activity is shared by select structurally similar metabolites, is not dependent on covalent protein modification, pH, or solute load, and is observable in mouse brain in vivo after delivery of a ketone ester. Furthermore, this phenotype is selective for pathological proteins such as amyloid-β, and exogenous βHB ameliorates pathology in nematode models of amyloid-β aggregation toxicity. We have generated a comprehensive atlas of the βHB-induced protein insolublome ex vivo and in vivo using mass spectrometry proteomics, and have identified common protein domains within βHB target sequences. Finally, we show enrichment of neurodegeneration-related proteins among βHB targets and the clearance of these targets from mouse brain, likely via βHB-induced autophagy. Overall, these data indicate a new metabolically regulated mechanism of proteostasis relevant to aging and AD.

Effects of antifouling compounds on the growth of macroalgae Undaria pinnatifida

Seaweeds are some of the principal primary producers of marine environments, and they are important ecological elements of coastal ecosystems. The effects of harmful chemicals on seaweeds may adversely affect coastal ecosystems, hence we aimed to develop a new phytotoxicity test using the gametophytes of a common temperate kelp species, Undaria pinnatifida (KU-1630), for the widely used antifouling chemical substances Cybutryne, Diuron, Cu2+, and Zn2+. Toxicity to gametophytes of U. pinnatifida was assessed by comparing the relative growth rate (RGR) at the logarithmic growth phase. Fragmentation method, initial algal biomass, photon irradiance, and adhesive period were investigated for developing optimal test conditions. Cybutryne exposure tests were performed with seven replicates and control, the RGR ranging from 0.17 to 0.19, while mean 7-day EC50 and no observed effect concentration (NOEC) were 5.1 μg/L and 1.8 μg/L, respectively. The 7-day EC50 for other antifoulants was 14 μg/L for Diuron, 17 μg/L for Cu2+, and 1500 μg/L for Zn2+. This test method demonstrated high sensitivity and reproducibility, and it may be added to the routine methods used for toxicity evaluation of hazardous chemicals.

NMR determination of the 2:1 binding complex of naphthyridine carbamate dimer (NCD) and CGG/CGG triad in double-stranded DNA

Trinucleotide repeat (TNR) diseases are caused by the aberrant expansion of CXG (X = C, A, G and T) sequences in genomes. We have reported two small molecules binding to TNR, NCD, and NA, which strongly bind to CGG repeat (responsible sequence of fragile X syndrome) and CAG repeat (Huntington's disease). The NMR structure of NA binding to the CAG/CAG triad has been clarified, but the structure of NCD bound to the CGG/CGG triad remained to be addressed. We here report the structural determination of the NCD-CGG/CGG complex by NMR spectroscopy and the comparison with the NA-CAG/CAG complex. While the NCD-CGG/CGG structure shares the binding characteristics with that of the NA-CAG/CAG complex, a significant difference was found in the overall structure caused by the structural fluctuation at the ligand-bound site. The NCD-CGG/CGG complex was suggested in the equilibrium between stacked and kinked structures, although NA-CAG/CAG complex has only the stacked structures. The dynamic fluctuation of the NCD-CGG/CGG structure at the NCD-binding site suggested room for optimization in the linker structure of NCD to gain improved affinity to the CGG/CGG triad.

Anti-PD-1 antibody monotherapy versus anti-PD-1 plus anti-CTLA-4 combination therapy as first-line immunotherapy in unresectable or metastatic mucosal melanoma: a retrospective, multicenter study of 329 Japanese cases (JMAC study)

Background

Anti-programmed cell death protein 1 (PD-1) antibody monotherapy (PD1) has led to favorable responses in advanced non-acral cutaneous melanoma among Caucasian populations; however, recent studies suggest that this therapy has limited efficacy in mucosal melanoma (MCM). Thus, advanced MCM patients are candidates for PD1 plus anti-cytotoxic T lymphocyte-associated antigen-4 (CTLA-4) combination therapy (PD1 + CTLA4). Data on the efficacy of immunotherapy in MCM, however, are limited. We aimed to compare the efficacies of PD1 and PD1 + CTLA4 in Japanese advanced MCM patients.

Patients and methods

We retrospectively assessed advanced MCM patients treated with PD1 or PD1 + CTLA4 at 24 Japanese institutions. Patient baseline characteristics, clinical responses (RECIST), progression-free survival (PFS), and overall survival (OS) were estimated using Kaplan–Meier analysis, and toxicity was assessed to estimate the efficacy and safety of PD1 and PD1 + CTLA4.

Results

Altogether, 329 patients with advanced MCM were included in this study. PD1 and PD1 + CTLA4 were used in 263 and 66 patients, respectively. Baseline characteristics were similar between both treatment groups, except for age (median age 71 versus 65 years; P < 0.001). No significant differences were observed between the PD1 and PD1 + CTLA4 groups with respect to objective response rate (26% versus 29%; P = 0.26) or PFS and OS (median PFS 5.9 months versus 6.8 months; P = 0.55, median OS 20.4 months versus 20.1 months; P = 0.55). Cox multivariate survival analysis revealed that PD1 + CTLA4 did not prolong PFS and OS (PFS: hazard ratio 0.83, 95% confidence interval 0.58-1.19, P = 0.30; OS: HR 0.89, 95% confidence interval 0.57-1.38, P = 0.59). The rate of ≥grade 3 immune-related adverse events was higher in the PD1 + CTLA4 group than in the PD1 group (53% versus 17%; P < 0.001).

Conclusions

First-line PD1 + CTLA4 demonstrated comparable clinical efficacy to PD1 in Japanese MCM patients, but with a higher rate of immune-related adverse events.

•

Anti-PD-1 plus anti-CTLA-4 antibody therapy (PD1 + CTLA4) is an option for patients with advanced mucosal melanoma (MCM).

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Data on the efficacy of PD1 + CTLA4 compared with PD-1 monotherapy (PD1) for MCM, however, are limited.

•

We retrospectively analyzed data from 329 Japanese patients with advanced MCM treated with PD1 or PD1 + CTLA4.

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No significant differences in objective response rate, progression-free survival, or overall survival were observed.

•

Immune-related adverse events resulting in treatment cessation were higher in the PD1 + CTLA4 group.

Enhanced thermal conduction by surface phonon-polaritons

Improving heat dissipation in increasingly miniature microelectronic devices is a serious challenge, as the thermal conduction in nanostructures is markedly reduced by increasingly frequent scattering of phonons on the surface. However, the surface could become an additional heat dissipation channel if phonons couple with photons forming hybrid surface quasiparticles called surface phonon-polaritons (SPhPs). Here, we experimentally demonstrate the formation of SPhPs on the surface of SiN nanomembranes and subsequent enhancement of heat conduction. Our measurements show that the in-plane thermal conductivity of membranes thinner than 50 nm doubles up as the temperature rises from 300 to 800 kelvin, while thicker membranes show a monotonic decrease. Our theoretical analysis shows that these thickness and temperature dependencies are fingerprints of SPhP contribution to heat conduction. The demonstrated thermal transport by SPhPs can be useful as a previously unidentified channel of heat dissipation in a variety of fields including microelectronics and silicon photonics.

Alteration in faecal bile acids, gut microbial composition and diversity after laparoscopic sleeve gastrectomy

Background

Laparoscopic sleeve gastrectomy (LSG) is a well established treatment for severe obesity and type 2 diabetes. Although the gut microbiota is linked to the efficacy of LSG, the underlying mechanisms remain elusive. The effect of LSG for morbid obesity on the gut microbiota and bile acids was assessed here.

Methods

Severely obese subjects who were candidates for LSG were included and followed until 6 months after surgery. The composition and abundance of the microbiota and bile acids in faeces were assessed by 16S ribosomal RNA sequencing, quantitative PCR and liquid chromatography–mass spectrometry.

Results

In total, 28 patients with a mean(s.d.) BMI of 44·2(6·6) kg/m2 were enrolled. These patients had achieved excess weight loss of 53·2(19·0) per cent and showed improvement in metabolic diseases by 6 months after LSG, accompanied by an alteration in the faecal microbial community. The increase in α-diversity and abundance of specific taxa, such as Rikenellaceae and Christensenellaceae, was strongly associated with reduced faecal bile acid levels. These changes had a significant positive association with excess weight loss and metabolic alterations. However, the total number of faecal bacteria was lower in patients before (mean(s.d.) 10·26(0·36) log10 cells per g faeces) and after (10·39(0·29) log10 cells per g faeces) operation than in healthy subjects (10·83(0·27) log10 cells per g faeces).

Conclusion

LSG is associated with a reduction in faecal bile acids and greater abundance of specific bacterial taxa and α-diversity that may contribute to the metabolic changes.

A self-reported measurement scale on a potential component of competency in the healthcare staff engaged in the prevention and control of non-communicable disease in Fiji

Background

According to the World Health Organization, an estimated 80% or more deaths in Pacific island countries, including Fiji, were related to non-communicable diseases (NCDs). Although competency-based approaches have been effective for developing healthcare workers’ capabilities, there are only a few reports on competency scales of healthcare workers for NCD prevention. We aimed to develop a self-reported measurement scale on a potential component of competency in the healthcare staff engaged in the prevention and control of NCDs in Fiji.

Methods

There were 378 Ministry of Health and Medical Services staff members working on NCD prevention and control in Fiji included in this study, which was a cross-sectional survey of social factors, working situation factors, and competency. Exploratory factor analysis was conducted to assess potential competency components, whereas Cronbach’s α coefficient and analysis of variance were used to assess the validity and reliability of the scale items, respectively. Multivariate regression analyses were conducted to analyze the respondents’ factor scores relative to social status and work situations.

Results

The factor analysis revealed 16 items that identified competency in four work types: 1) work management, 2) monitoring and evaluation, 3) community partnership, and 4) community diagnosis. The monitoring and evaluation roles were related to ethnic background, community partnership was related to religion, and community diagnosis was related to academic qualifications.

Conclusions

Based on the results, we developed a competency scale for the four work types. This scale can help healthcare workers engage in better management of residents with NCDs in Fiji.

A candidate-SNP retrospective cohort study for fracture risk in Japanese Thoroughbred racehorses

Fractures are medical conditions that compromise the athletic potential of horses and/or the safety of jockeys. Therefore, the reduction of fracture risk is an important horse and human welfare issue. The present study used molecular genetic approaches to determine the effect of genetic risk for fracture at four candidate SNPs spanning the myostatin (MSTN) gene on horse chromosome 18. Among the 3706 Japanese Thoroughbred racehorses, 1089 (29.4%) had experienced fractures in their athletic life, indicating the common occurrence of this injury in Thoroughbreds. In the case/control association study, fractures of the carpus (carpal bones and distal radius) were statistically associated with g.65809482T/C (P = 1.17 x 10^-8 ), g.65868604G/T (P = 2.66 x 10^-9 ), and g.66493737C/T (P = 6.41 x 10^-8 ). In the retrospective cohort study using 1710 racehorses born in 2000, the relative risk (RR) was highest for male horses at g.65868604G/T, based on the dominant allele risk model (RR = 2.251, 95% confidence interval 1.407-3.604, P = 0.00041), and for female horses at g.65868604G/T, based on the recessive allele risk model (RR = 2.313, 95% confidence interval 1.380-3.877, P = 0.00163). Considering the association of these SNPs with racing performance traits such as speed, these genotypes may affect the occurrence of carpus fractures in Japanese Thoroughbred racehorses as a consequence of the non-genetic influence of the genotype on the distance and/or intensity of racing and training. The genetic information presented here may contribute to the development of strategic training programs and racing plans for racehorses that improve their health and welfare.

The safety and effectiveness profile of eldecalcitol in a prospective, post-marketing observational study in Japanese male patients with osteoporosis

We conducted a post-marketing observational study to investigate the safety and effectiveness of eldecalcitol for the treatment of osteoporosis in a Japanese clinical setting. The observation period was 12 months for women and 36 months for men. The final results for the female patients have already been published. In this article, the final results for the male patients are reported. A total of 470 male osteoporosis patients were enrolled. The safety analysis set included 431 patients (mean age, 76.8 years; mean ± SD follow-up period, 631.0 ± 450.3 days), and 175 patients continued treatment throughout the 3-year observational period. Adverse drug reactions (ADRs) were reported in 28 patients (6.49%); the most common ADRs were hypercalcemia (1.16%) and renal impairment (1.16%). Serious ADRs were reported in 5 patients (1.16%). Mean serum calcium was within the normal range throughout the observation period. The cumulative incidence of new vertebral and nonvertebral fractures at 36 months, estimated by Kaplan-Meier analysis, was 10.23 and 4.06%, respectively. At the last observation, mean lumbar spine bone mineral density was 3.49% higher (P < 0.0001) than at baseline, and levels of the bone turnover markers BAP and TRACP-5b were reduced (-14.64%; P = 0.0009, and - 29.51%; P < 0.0001, respectively). In conclusion, the safety and effectiveness of eldecalcitol for the treatment of Japanese male osteoporosis patients was confirmed in clinical practice. Careful monitoring of serum calcium and estimated glomerular filtration rate, both before and during treatment, is necessary to minimize the risk of hypercalcemia and renal impairment while maximizing the effectiveness of eldecalcitol.

A case of nivolumab-induced acute-onset type 1 diabetes mellitus in melanoma

Nivolumab, an anti-PD-1 antibody, is now considered an important therapeutic agent in several advanced malignancies. However, immune-related adverse events such as endocrinopathies have been reported with its use. Thyroid disorder and isolated adrenocorticotropic hormone deficiency have frequently been reported as nivolumab-induced immune-related adverse events. Another endocrinopathy is nivolumab-induced type 1 diabetes mellitus (t1dm), described as diabetes mellitus with rapid onset and complete insulin insufficiency, at times leading to fulminant t1dm. We report the case of a 68-year-old woman who developed pancreatic islet-related autoantibody-negative t1dm, possibly induced by nivolumab, under continuous glucocorticoid administration. She was treated with nivolumab for advanced malignant melanoma, concomitant with 10 mg prednisolone daily for thrombophlebitis tapered to 5 mg after 13 courses of nivolumab therapy. At approximately the 27th course of nivolumab therapy, she showed elevated plasma glucose levels despite preserved insulin secretion. A month later, she developed diabetic ketoacidosis. Her insulin secretion decreased and finally was exhausted. She was diagnosed with acute-onset rather than fulminant t1dm because of a rapidly progressive course to diabetic ketoacidosis during just more than 1 week. She is currently receiving insulin replacement. There has been no recurrence of the melanoma. Thus, nivolumab might induce autoimmune diabetes mellitus, with patients having t1dm-sensitive human leucocyte antigen being more susceptible even when receiving glucocorticoids. Physicians should be aware that nivolumab could potentially induce t1dm as a critical immune-related adverse event.

Brillouin Light Scattering by Magnetic Quasivortices in Cavity Optomagnonics

A ferromagnetic sphere can support optical vortices in the form of whispering gallery modes and magnetic quasivortices in the form of magnetostatic modes with nontrivial spin textures. These vortices can be characterized by their orbital angular momenta. We experimentally investigate Brillouin scattering of photons in the whispering gallery modes by magnons in the magnetostatic modes, zeroing in on the exchange of the orbital angular momenta between the optical vortices and magnetic quasivortices. We find that the conservation of the orbital angular momentum results in different nonreciprocal behavior in the Brillouin light scattering. New avenues for chiral optics and optospintronics can be opened up by taking the orbital angular momenta as a new degree of freedom for cavity optomagnonics.

Aluminium nanopillars reduce thermal conductivity of silicon nanobeams

In search of efficient thermoelectric nanostructures, many theoretical works predicted that nanopillars, placed on the surface of silicon membranes, nanobeams, or nanowires, can reduce the thermal conductivity of these nanostructures. To verify these predictions, we experimentally investigate heat conduction in suspended silicon nanobeams with periodic arrays of aluminium nanopillars. Our room temperature time-domain thermoreflectance experiments show that the nanobeams with nanopillars have 20% lower thermal conductivity as compared to pristine nanobeams. We discuss possible explanations of these data, including coherent effects, and conclude that the thermal conductivity is reduced mainly by phonon scattering at the pillar/beam interface due to the intermixing of aluminium and silicon atoms, as supported by the transmission electron microscopy. As this intermixing does not only reduce thermal conductivity but may also increase electrical conductivity, these nanostructures are exceptionally promising for thermoelectric applications.

Lower-limb muscle strength according to bodyweight and muscle mass among middle age patients with type 2 diabetes without diabetic neuropathy

[Purpose] This study assessed the effects of type 2 diabetes without diabetic polyneuropathy on muscle strength according to body composition in middle age patients. [Subjects and Methods] This study included 45 non-diabetic individuals (control group) and 50 patients with type 2 diabetes (DM group), 40 to 64 years of age. The body composition was examined, including the leg muscle volume (LMV), which was the sum of the lower-limb muscle mass. The muscle strength was also examined, and the knee extension force (KEF), ankle dorsiflexion force (ADF). The KEF and ADF were normalized to the bodyweight, and the total leg muscle force (TLMF) were calculated by combining the KEF and ADF. The leg muscle quality (LMQ) was calculated as the TLMF normalized with the LMV. [Results] While no significant differences were found in the LMV between groups, the body mass index were higher in the DM group than in the control group. Significant differences were observed in %KEF, %ADF, and the LMQ in the DM group, with 15.8%, 18.7%, and 11.5% lower values than those in the control group, respectively. [Conclusion] The results of this study may demonstrate that muscle weakness occurs before diabetes progresses to a severe condition.

The safety and effectiveness profile of eldecalcitol in a prospective, post-marketing observational study in Japanese patients with osteoporosis: interim report

This large-scale post-marketing surveillance study was conducted to assess the safety and effectiveness of eldecalcitol treatment in patients with osteoporosis in a Japanese clinical setting. A total of 3567 patients with osteoporosis were enrolled and received eldecalcitol 0.75 μg/day for 12 months. For this interim report, 3285 patients were eligible for analysis. Mean age was 74.9 ± 8.7 years; 86.8 % (2854/3285) were women. There were 142 reported adverse drug reactions (ADRs) in 129 patients (3.92 % of the total 3285 patients): the most common were hypercalcemia and increased blood calcium (0.88 %), renal impairment (0.27 %), abdominal discomfort (0.24 %), constipation (0.24 %), and pruritus (0.24 %). The incidence of ADRs was 5.10 % in men and 3.74 % in women. Although 10 serious ADRs were reported in 9 patients (0.27 %), no clinically significant safety issues were identified. Incidence of hypercalcemia or increased blood calcium was 8.47 % in patients with renal impairment and only 0.74 % in patients without renal impairment. At last observation, the incidence of new vertebral and nonvertebral fractures was 2.44 % and 1.70 %, respectively. There was a significant increase in bone mineral density at the lumbar spine and distal radius. The bone turnover markers BAP, serum NTX, urinary NTX, and TRACP-5b were suppressed by eldecalcitol treatment in both sexes. In conclusion, consistent with the findings of the phase III pivotal clinical trial, eldecalcitol was shown to have a favorable safety profile and effectiveness in Japanese patients with osteoporosis. However, periodic measurements of serum calcium were required to prevent occurrence of hypercalcemia during eldecalcitol treatment, especially in patients with renal impairment.

Thinning of articular cartilage after joint unloading or immobilization. An experimental investigation of the pathogenesis in mice

OBJECTIVE

Moderate mechanical stress generated by normal joint loading and movement is essential for the maintenance of healthy articular cartilage. However, the effects of reduced loading caused by the absence of weight bearing or joint motion on articular cartilage and subchondral bone is still poorly understood. We aimed to characterize morphological and metabolic responses of articular cartilage and subchondral bone to decreased mechanical stress in vivo.

METHODS

Mice were subjected to periods of hindlimb unloading by tail suspension or external fixation of the knee joints. The articular surface was observed with digital microscope and the epiphyseal bone was assessed by micro-CT analysis. Articular cartilage and subchondral bone were further evaluated by histomorphometric, histochemical, and immunohistochemical analyses.

RESULTS

The joint surface was intact, but thickness of both the total and uncalcified layer of articular cartilage were decreased both after joint unloading and immobilization. Subchondral bone atrophy with concomitant marrow expansion predisposed osteoclast activity at bone surface to invade into cartilaginous layer. Uncalcified cartilage showed decreased aggrecan content and increased aggrecanase expression. Alkaline phosphatase (ALP) activity was increased at uncalcified cartilage, whereas decreased at calcified cartilage. The distributions of hypertrophic chondrocyte markers remained unchanged.

CONCLUSION

Thinning of articular cartilage induced by mechanical unloading may be mediated by metabolic changes in chondrocytes, including accelerated aggrecan catabolism and exquisitely modulated matrix mineralization, and cartilage matrix degradation and resorption by subchondral osteoclasts. Cartilage degeneration without chondrocyte hypertrophy under unloading condition indicate the possible existence of mechanism which is different from osteoarthritis pathogenesis.

Plutonium, 137Cs and uranium isotopes in Mongolian surface soils

Plutonium (²³⁸Pu and ^239,240Pu), ¹³⁷Cs and plutonium activity ratios (²³⁸Pu/^239,240Pu) as did uranium isotope ratio (²³⁵U/²³⁸U) were measured in surface soil samples collected in southeast Mongolia. The ^239,240Pu and ¹³⁷Cs concentrations in Mongolian surface soils (<53 μm of particle size) ranged from 0.42 ± 0.03 to 3.53 ± 0.09 mBq g^-1 and from 11.6 ± 0.7 to 102 ± 1 mBq g^-1, respectively. The ²³⁸Pu/^239,240Pu activity ratios in the surface soils (0.013-0.06) coincided with that of global fallout. The ²³⁵U/²³⁸U atom ratios in the surface soil show the natural one. There was a good correlation between the ^239,240Pu and ¹³⁷Cs concentrations in the surface soils. We introduce the migration depth to have better understanding of migration behaviors of anthropogenic radionuclides in surface soil. We found a difference of the migration behavior between ^239,240Pu and ¹³⁷Cs from ¹³⁷Cs/^239,240Pu - ¹³⁷Cs plots for the Mongolian and Tsukuba surface soils; plutonium in surface soil is migrated easier than ¹³⁷Cs.

Quantitating the lateral skin stiffness by a new and versatile electro-mechanical instrument. Preliminary studies

BACKGROUND

A new electro-mechanical device for measuring the lateral stiffness of the skin is now available. It basically allows to recording the forces that the skin opposes to a lateral displacement (1-2 mm) of a pinching type movement. Preliminary assays of this device to various skin sites and an artificial substrate aimed at defining its major characteristics (sensitivity, reproducibility, variations according to skin site).

METHODS

The calibration of the device (Khelometer^® ) and assessment of its reproducibility were carried out through the use of elastometer substrates of various stiffness's. The device was then used, in vivo, at different skin sites (scalp, inner and outer forearms, cheeks) of 213 healthy Japanese women of various ages. The short-time effect of a hydrating regimen (7% glycerol) was recorded on the outer forearm.

RESULTS

This new device offers an appreciable reproducibility in vitro and in vivo (coefficient of variation of 2-4% and 5-14%, respectively). Unlike other biophysical methods, the Khelometer^® can be easily applied onto the human scalp that shows a higher stiffness than the two other skin sites, increasing with age and presence of alopecia. In all the three studied skin sites, the impact of age leads to significantly higher lateral skin stiffness (LSS, expressed as N/mm) values. The latter were found significantly different between the two sides of the forearms where the outer (sun-exposed) side showed statistically slightly higher LSS, than the unexposed inner side. LSS values found on cheeks (≈0.5 N/mm) were about four times lower than those of the scalp (≈2 N/mm) and about half those of forearms (≈1 N/mm). The effect of a 7% glycerol based formula was recorded 20 min post application onto the forearm, leading to a slight drop in LSS (approx. 15%) as compared to a vehicle-applied skin site.

CONCLUSION

These preliminary studies clearly indicate that this new device, applicable to any skin site, offers appreciable assets such as sensitivity and reproducibility. Accordingly, it appears as a new approach in the non-invasive biophysical measurements of the skin surface, in both advanced and applied research investigations.

Development and inter-laboratory study of a method for quantifying zearalenone in pet foods

An analytical method for quantifying zearalenone (ZEA) in pet foods using a liquid chromatograph-atmospheric pressure chemical ionization-mass spectrometer (LC-APCI-MS) was developed, and an inter-laboratory study was conducted. ZEA was extracted from pet food samples with aqueous acetonitrile. The extract was purified using a multifunctional column, MultiSep 226 Aflazon+, and analysed with LC-APCI-MS. The limit of quantification of ZEA by this method was estimated to be 0.2 mg/kg for dry and semi-dry pet foods, and 0.1 mg/kg for wet pet food. The calibration curve of ZEA for this method showed linearity in the range of 0.1-10 ng of ZEA (0.01-1.0 µg/ml, 0.04-4.0 mg/kg matrix). The mean recoveries, repeatabilities, reproducibilities, and the HorRats for ZEA from the inter-laboratory validation study were 99.0-102%, 2.2-3.0%, 5.6-6.6%, and 0.33-0.36, respectively.

The development and piloting of a leadership questionnaire for general dental practitioners: preliminary results from the North West of England and Tokyo

OBJECTIVES

Key reforms in England and Japan have called for greater clinical leadership from general dental practitioners to deliver improvements in the quality of care for patients. In England, the reorganisation of the National Health Service has led to the development of Local Professional Networks to ensure services are clinically led, patient and outcome focused. In Japan, the rapidly changing demographics have led to calls for general dental practitioners to become more active in meeting the emerging population health challenges. Both require engagement at a strategic and a local level. However, little is known about what is meant by clinical leadership in dentistry or what training needs exist. The aim of this study was to develop and pilot a questionnaire to understand what general dental practitioners feel is important about clinical leadership and how they rate themselves.

METHODS

A 61-item questionnaire was developed from the literature, an earlier qualitative study and refined through cognitive interviews. Questionnaires were distributed to general dental practitioners across the North West of England and Tokyo, using random sequence generation. For each item, the participant had to record whether they thought the statement was an important component of clinical leadership and how they rated themselves. Both were rated using a seven-point Likert scale. Data reduction was undertaken using principal component analysis to examine for factor loadings within the questionnaire. Differences in mean scores were also used to highlight substantive differences in how general dental practitioners rated the different components of leadership and how they rated themselves.

RESULTS

The response rate for the pilot was low (22.9% and 7.5% for North West and Tokyo respectively). The items that were considered to be important in leadership reduced to two components in the North West (accounting for 62.1% of the total variance): 'How to lead' and 'How not to lead'. In Tokyo, 56.4% of the total variance was explained by three components: 'Demonstrating personal qualities', 'Working with others' and 'How not to lead'. When the self-rated items were reduced, three factors were found to be important in the North West: 'Working with others', 'Setting direction' and 'Managing services' (55.1% of the variance). 'Working with others', 'Demonstrating personal qualities', 'Pragmatism', 'Setting direction' and 'Improving services' were found to be important in Tokyo (52.8% of the variance). The questionnaire items relating to integrity, team-working and having a positive attitude during difficult times were rated highly by both groups. Items relating to providing vision for team, being assertive and having a positive attitude had the greatest mean difference, suggesting possible areas of training need.

CONCLUSION

The nature of the pilot study and the poor response rate makes any conclusion difficult to infer. Among those that participated, leadership was understood to be more important at a practice level rather than at a strategic level. The questionnaire should be refined further based on the results of the pilot and the data reduction.

Pre-Embolization Study of Ruptured Cerebral Aneurysms with Helical CT

Sixteen ruptured aneurysms in 16 patients considered endovascular embolizations were examined. The findings of axial source images (axial images) and reconstructed three-dimensional CT angiography (3D-CTA) of helical CT were compared to those of rotational digital subtraction angiography (DSA). The aneurysmal neck and arterial branches adjacent to the neck were closely investigated.

In seven out of 16 cases (43.8%), information provided by axial images and/or 3D-CTA was more useful than that of rotational DSA in evaluating the aneurysmal neck and arterial branches. Helical CT can provide valuable information on ruptured aneurysms that cannot be obtained by rotational DSA in some patients.

This technique is useful to obtain anatomical information about aneurysms and to select the best therapeutic method.

Cavity Optomagnonics with Spin-Orbit Coupled Photons

We experimentally implement a system of cavity optomagnonics, where a sphere of ferromagnetic material supports whispering gallery modes (WGMs) for photons and the magnetostatic mode for magnons. We observe pronounced nonreciprocity and asymmetry in the sideband signals generated by the magnon-induced Brillouin scattering of light. The spin-orbit coupled nature of the WGM photons, their geometrical birefringence, and the time-reversal symmetry breaking in the magnon dynamics impose the angular-momentum selection rules in the scattering process and account for the observed phenomena. The unique features of the system may find interesting applications at the crossroad between quantum optics and spintronics.

Pharmacokinetics of procaterol in thoroughbred horses

Procaterol (PCR) is a beta-2-adrenergic bronchodilator widely used in Japanese racehorses for treating lower respiratory disease. The pharmacokinetics of PCR following single intravenous (0.5 μg/kg) and oral (2.0 μg/kg) administrations were investigated in six thoroughbred horses. Plasma and urine concentrations of PCR were measured using liquid chromatography-mass spectrometry. Plasma PCR concentration following intravenous administration showed a biphasic elimination pattern. The systemic clearance was 0.47 ± 0.16 L/h/kg, the steady-state volume of the distribution was 1.21 ± 0.23 L/kg, and the elimination half-life was 2.85 ± 1.35 h. Heart rate rapidly increased after intravenous administration and gradually decreased thereafter. A strong correlation between heart rate and plasma concentration of PCR was observed. Plasma concentrations of PCR after oral administration were not quantifiable in all horses. Urine concentrations of PCR following intravenous and oral administrations were quantified in all horses until 32 h after administration. Urine PCR concentrations were not significantly different on and after 24 h between intravenous and oral administrations. These results suggest that the bioavailability of orally administrated PCR in horses is very poor, and the drug was eliminated from the body slowly based on urinary concentrations. This report is the first study to demonstrate the pharmacokinetic character of PCR in thoroughbred horses.

Development and inter-laboratory study of a method for quantification of fumonisin B1, B2 and B3 in pet foods

An analytical method to determine fumonisin B1 (FB1), B2 (FB2) and B3 (FB3) in pet foods using a liquid chromatography-electrospray ionization-mass spectrometer (LC-ESI-MS) was developed, and an inter-laboratory study was conducted in eleven laboratories. FB1, FB2 and FB3 were extracted with aqueous acetonitrile. The extract was purified by a multifunctional column, MultiSep 211 Fum, and analysed by LC-ESI-MS. The limit of quantification of fumonisins was estimated to be 0.2 mg/kg for dry and semi-dry pet foods, and 0.1 mg/kg for wet pet food. The calibration curve showed linearity in the range of 0.1-5 ng of fumonisins (0.02-1.0 μg/ml). The values of the mean recovery for FB1 at 0.1-1.0 mg/kg were 93.3-107% and of the relative standard deviation less than 7.9%. These values were 87.3-102 and 8.6% for FB2 and 90.8-102 and 8.6% for FB3, respectively. The mean recovery, repeatability, reproducibility and the Horwitz ratio for FB1 from the inter-laboratory validation study were 92.9-98.9%, 2.6-4.6%, 6.8-10% and 0.41-0.54, respectively. The values for FB2 were 91.5-94.7%, 2.7-5.9%, 6.8-8.9% and 0.33-0.55, respectively, and the values for FB3 were 90.1-94.3%, 3.3-5.9%, 7.3-9.5% and 0.44-0.57, respectively.

Predictive factors for pericardial effusion identified by heart dose-volume histogram analysis in oesophageal cancer patients treated with chemoradiotherapy

OBJECTIVE

To identify predictive factors for the development of pericardial effusion (PCE) in patients with oesophageal cancer treated with chemotherapy and radiotherapy (RT).

METHODS

From March 2006 to November 2012, patients with oesophageal cancer treated with chemoradiotherapy (CRT) using the following criteria were evaluated: radiation dose >50 Gy; heart included in the radiation field; dose-volume histogram (DVH) data available for analysis; no previous thoracic surgery; and no PCE before treatment. The diagnosis of PCE was independently determined by two radiologists. Clinical factors, the percentage of heart volume receiving >5-60 Gy in increments of 5 Gy (V5-60, respectively), maximum heart dose and mean heart dose were analysed.

RESULTS

A total of 143 patients with oesophageal cancer were reviewed retrospectively. The median follow-up by CT was 15 months (range, 2.1-72.6 months) after RT. PCE developed in 55 patients (38.5%) after RT, and the median time to develop PCE was 3.5 months (range, 0.2-9.9 months). On univariate analysis, DVH parameters except for V60 were significantly associated with the development of PCE (p < 0.001). No clinical factor was significantly related to the development of PCE. Recursive partitioning analysis including all DVH parameters as variables showed a V10 cut-off value of 72.8% to be the most influential factor.

CONCLUSION

The present results showed that DVH parameters are strong independent predictive factors for the development of PCE in patients with oesophageal cancer treated with CRT.

ADVANCES IN KNOWLEDGE

A heart dosage was associated with the development of PCE with radiation and without prophylactic nodal irradiation.

Effect of Pre-Molding Process and Additive of Injection Molded Wood/PP Composites

Injection molded composites are becoming more widespread in recent years because of their high quality and low cost. However, compared to synthetic fiber composites, it is difficult to maintain a constant fiber volume fraction and uniform distribution for natural fiber composites during the direct injection process. This is mainly because natural fibers are more easily twisted during feeding into the injection machine, owing to their rough surfaces. These feeding difficulties are particularly due to the low bulk densities of natural fibers, especially natural fillers. Additional challenges to the injection process include the concentration and, especially for natural filler reinforced composite. To address these problems, the current study investigates the mechanical properties and morphologies of polypropylene (PP) reinforced by wood powder. Two pre-molding processes, dry-blending and compounding, were compared, and the effects of an additive (crystalline polyalpha olefin (CPAO)) on the mechanical properties of the wood/PP composites were investigated. This investigation is based on tensile, three point bending, and Izod impact tests, and scanning electron microscope (SEM) observation of the fracture surfaces. Results indicated that the composites molded through compounding exhibited better mechanical properties than the samples molded through the direct dry-blending process. In addition, the tensile and bending properties of the composites produced through compounding were found to increase with the addition of CPAO content, because of improved wood powder distribution in the PP matrix.

An Anomalous Isotope Effect of 235U in U(IV)-U(VI) Chemical Exchange

The abundance ratios of 234U, 235U, 236U and 238U were determined by mass spectrometry on uranium samples obtained from a chromatographic uranium enrichment process based on the U(IV) - U(VI) chemical exchange reaction. According to standard theory, the elementary isotope effect in processes based on equilibrium chemical exchange is proportional to the mass difference of the isotopes. In the present work this has been confirmed for 234U, 236U and 238U. However, according to the observed data the fractionation between 234U and 235U is much smaller than the one between 235U and 236U in spite of the same mass difference in either isotopic pair. The anomaly of the fractionation is concluded to be due to the characteristics of 235U, which is the only odd mass number isotope in the present system.

Cultural differences in clinical leadership: a qualitative study comparing the attitudes of general dental practitioners from Greater Manchester and Tokyo

BACKGROUND AND AIMS

Leadership has been argued to be a key component in the transformation of services in the United Kingdom and in Japan. In the UK, local professional networks have developed to provide clinician led care in dentistry; working to develop local plans to deliver improvements in the quality of care for patients. In Japan, the remuneration model for dental care has been revised with the aim to improve the service and tackle the current challenges of population health there. The aim of this study was to use semi-structured interviews and thematic analysis to explore general dental practitioners' (GDPs) understanding of the term 'leadership' and determine whether its meaning is culturally bound.

METHODS

Twelve participants were sampled purposively by the research team; identifying GDPs involved in leadership roles from across Greater Manchester and Tokyo. A set of open-ended questions was developed for semi-structured interviews a priori and the interviews continued until saturation. Interviews were recorded, transcribed verbatim and codes were developed into a coding frame for thematic analysis. Representative quotations are provided in the results.

RESULTS

Fourteen codes were identified according to the aims of the study and organised into five overarching themes. 'Leadership as the relationship' was more pronounced among Japanese GDPs, while 'leadership as the individual' was common in GDPs from Greater Manchester. Differences were also found in respect of education and training in leadership. Training was also considered to be important by the GDPs from Japan, while UK GDPs felt leaders were more likely to be influenced by innate qualities. The interdependence of leadership and entrepreneurship was raised by both sets of GDPs.

CONCLUSION

The concept of leadership was considered to be important by GDPs from both Greater Manchester and Tokyo; leadership was seen as providing strategy and direction for a clinical team. However, cultural influences were evident in how this was conceptualised.