Corticospinal excitability changes during muscle relaxation and contraction in motor imagery.

To enhance smooth muscle contraction and relaxation during rehabilitation and sports activities, a comprehensive understanding of the motor control mechanisms within the central nervous system is necessary. However, current knowledge on these aspects is insufficient. Therefore, this study aimed to deepen our understanding of motor controls, by investigating the alterations in corticospinal excitability within cortical motor areas related to muscle contraction and relaxation using motor imagery with a reaction time task paradigm. Transcranial magnetic stimulation was used to measure the motor-evoked potentials in the first dorsal interosseous muscle of the right hand after the 'go' signal. Static weak muscle contraction (Experiment 1: 18 healthy participants) and resting state (Experiment 2: 16 healthy participants) were applied as background factors, and a trial without motor imagery was performed as a control. Muscle contraction was maintained in the background in the contraction motor imagery. A decrease in excitability in the relaxation motor imagery task occurred compared with the control. When the muscles were at rest, an increase in excitability in the contraction motor imagery and a transient increase in excitability in the relaxation motor imagery occurred compared with the control condition. Hence, the excitability of contraction and relaxation motor imagery is characterized by a continuous increase in excitability, transient increase and subsequent decrease in excitability, respectively. These results suggest that muscle contraction sensory information in the background condition may be necessary for muscle relaxation. Matching the background conditions may be crucial when utilizing motor imagery for rehabilitation or sports training.

The effect of initiation prediction and non-prediction on muscle relaxation control.

[Purpose] This study aimed to examine the difference in the excitability of the primary motor cortex between initiation-predictive and non-predictive tasks, where the onset of muscle relaxation is predicted and not predicted, respectively. [Participants and Methods] Seventeen participants were asked to perform rapid muscle relaxation either through an initiation-predictive or non-predictive task. The baseline was set at 20 percent of the maximum voluntary contraction. Motor-evoked potentials and H-reflexes elicited by transcranial magnetic stimulation and median nerve electrical stimulation, respectively, were measured. The mean stimulation time from the onset of relaxation was calculated, and the motor-evoked potentials and Hoffmann's reflexes elicited during the first (immediately before relaxation) and second half (long before relaxation) were compared. [Results] The amplitude of the motor-evoked potential significantly increased in both initiation-predictive and non-predictive tasks when compared to the baseline, indicating increased excitability of the primary motor cortex. The motor-evoked potential from the initiation-non-predictive task, but not the initiation-predictive task, was associated with increased excitability of the primary motor cortex immediately before relaxation. [Conclusion] Variations in the predictability of motor movements are associated with changes in muscle relaxation control in the central nervous system.

Determination of neurotransmitters in mouse brain using miniaturized and tableted QuEChERS for the sample preparation.

Neurotransmitters (NTs) are important endocrine molecules in the human body that have several characteristics and functions. Therefore, it is necessary to determine the accuracy and precision of the proposed method for the assessment of NTs functions. This study proposes a quick, easy, cheap, effective, rugged, and safe (QuEChERS) tablet for easy sample preparation and application to low-volume samples. We used response surface methodology to design and optimize the QuEChERS tablets. When we measured NTs in the brains of aged mice, whose samples were derivatized by DNS and extracted by QuEChERS, all analytes except VMA, NAS, 5-HTP, DOPA, and A, were detected in the mouse brain samples. Our approach may provide easy sample preparation and/or extraction techniques for small sample volumes, not only in animal samples but also in human samples to avoid invasive collection.

The application of multiple advanced chloride removal methods to synthesized Friedel's salt and municipal solid waste incineration bottom ash.

To recycle municipal solid waste incineration bottom ash as a cement raw material, it is important to reduce the Cl concentration in the ash. However, the reduction of chlorides by washing only has limited success due to the presence of insoluble Friedel's salt (FS) in the ash. Although some studies on the decomposition of FS and the application of advanced chloride removal methods to bottom ash have been reported, few studies have compared the effects of different removal methods. Moreover, due to the complex ash composition, it is also necessary to compare the effects on different ashes and pure FS. Therefore, in this study, we applied five advanced chloride removal methods to synthesized FS and two types of bottom ash (FS-High and FS-Low), and compared the effects. For both FS and bottom ash, all methods promoted chloride dissolution more than washing only. For FS, aging was the most effective method, with a Cl removal ratio of 73%. In contrast, for ash FS-High, aging increased the Cl removal ratio to 80% and decreased the Cl content to 2800 mg/kg. The FS-derived peak observed in an X-ray diffraction analysis disappeared following aging. For ash FS-Low, acid washing increased the Cl removal ratio to 64% and decreased the Cl content to 1800 mg/kg. The treatment with the highest removal ratio in each ash had the lowest pH. There was a significant correlation between pH and the Cl removal effect. The Cl remaining after the application of the methods was likely associated with Na.

Fluvastatin prevents the development of arthritis in env-pX rats via up-regulation of Rho GTPase-activating protein 12.

The pleiotropic effects of statins, including an antiarthritic potential, have been noted. This study aimed to determine the efficacy of statins on rheumatoid arthritis (RA) and clarify how statins affect its pathogenesis. Fluvastatin (500 µg/kg/day) or vehicle was given per os to env-pX rats, which carry the human T-cell leukemia virus type I env-pX gene and spontaneously develop destructive arthritis mimicking RA, for 30 days. Blood sampling and ultrasonography (US) of the ankle joints were conducted on days 0, 10, 20, and 30. On day 30, all rats were euthanized, and the ankle joints were subjected to histological analysis. To clarify how fluvastatin affects the pathogenesis of RA, comprehensive serum exosomal microRNA (miRNA) analysis was performed. Gene expression in the primary culture of synovial fibroblasts derived from arthritic rat and human and non-arthritic rat periarticular tissues was determined quantitatively by real-time reverse transcription-polymerase chain reaction (RT-PCR). As a result, the development of arthritis in env-pX rats was significantly suppressed by fluvastatin, which was evident from the viewpoints of serology, US imaging, and histology. Comprehensive serum exosomal miRNA analysis suggested that the expression of Rho GTPase-activating protein 12 (Arhgap12) was decreased in arthritic env-pX rats but increased with the administration of fluvastatin. Corresponding results were obtained by quantitative RT- PCR using primary culture of synovial fibroblasts. The collective findings suggest that fluvastatin prevents the development of arthritis in env-pX rats via the up-regulation of ARHGAP12. This study suggests that ARHGAP12 can be a possible therapeutic target of RA.

A Dementia Café as a Bridgehead for Community-Inclusive Care: Qualitative Analysis of Observations by On-the-Job Training Participants in a Dementia Café.

BACKGROUND/AIMS: Dementia cafés are becoming widespread as a new approach to dementia care, but their operational procedures and significance have not been adequately studied. METHODS: On-the-job training (OJT) for professionals planning to operate a dementia café in the future was conducted in a pioneering dementia café in Japan. The reports of OJT trainees' observations and learning were analyzed qualitatively. RESULTS: Reports could be summarized in up to 9 themes: 2 related to the atmosphere and significance of the café, 3 related to the guests, such as people with dementia and their families, and 4 related to the café staff. DISCUSSION: The results of the present study identified the elements that make up dementia cafés and their significance and suggest that dementia cafés could be a new type of community resource for dementia care in the future.

Logistical study in Hyogo prefecture on disposal of poultry carcasses infected with highly pathogenic avian influenza virus to prevent infection spreading to other flocks.

Establishment of a disposal plan for carcasses in advance is important for prevention of epidemics. A disposal plan for contaminated goods such as poultry carcasses infected with highly pathogenic avian influenza (HPAI) virus was studied in Hyogo Prefecture, Japan. We investigated all poultry farms with over 1,000 birds for their locations, species and numbers of birds, structure and size of poultry facilities and land spaces of the farms. Moreover, we judged whether they could dispose of all the carcasses at their farms. In 2005, 5.5 million layers and 2.7 million broilers were being kept. If HPAI had broken out, 44.0% of the farmers could bury all the carcasses, and 65.6% could compost them at their farms. However, 23.4% could not dispose of them except by burning them at incineration facilities. We decided to choose burning first for rapid disposal as long as the virus was not a pandemic type.