Digital Motor Biomarkers of Cerebellar Ataxia Using an RGB-Depth Camera-Based Motion Analysis System.

This study aimed to identify quantitative biomarkers of motor function for cerebellar ataxia by evaluating gait and postural control using an RGB-depth camera-based motion analysis system. In 28 patients with degenerative cerebellar ataxia and 33 age- and sex-matched healthy controls, motor tasks (short-distance walk, closed feet stance, and stepping in place) were selected from a previously reported protocol, and scanned using Kinect V2 and customized software. The Clinical Assessment Scale for the Assessment and Rating of Ataxia (SARA) was also evaluated. Compared with the normal control group, the cerebellar ataxia group had slower gait speed and shorter step lengths, increased step width, and mediolateral trunk sway in the walk test (all P < 0.001). Lateral sway increased in the stance test in the ataxia group (P < 0.001). When stepping in place, the ataxia group showed higher arrhythmicity of stepping and increased stance time (P < 0.001). In the correlation analyses, the ataxia group showed a positive correlation between the total SARA score and arrhythmicity of stepping in place (r = 0.587, P = 0.001). SARA total score (r = 0.561, P = 0.002) and gait subscore (ρ = 0.556, P = 0.002) correlated with mediolateral truncal sway during walking. These results suggest that the RGB-depth camera-based motion analyses on mediolateral truncal sway during walking and arrhythmicity of stepping in place are useful digital motor biomarkers for the assessment of cerebellar ataxia, and could be utilized in future clinical trials.

Age-related changes in standing ability on a foam surface based on the center-of-mass acceleration of each body segment.

[Purpose] The purpose of this study was to elucidate the age-related changes in the stability of the quiet standing posture based on the acceleration of the center of mass of each body segment under deteriorated somatosensory conditions. [Participants and Methods] The participants in this study were 18 healthy elderly persons and 11 healthy young adults. A foam surface was placed on the force plate for load-bearing onto the somatosensory system. The participants maintained a quiet position on the force plate under two conditions: a firm surface and a foam surface. The accelerations of the head, thorax, pelvis, and whole body center of mass when quiet standing in two conditions were measured by a motion capture system. In the statistical analysis, regarding the center of mass of each body segment, the interactions were examined by performing a two-way analysis of variance using age and surface condition as factors. [Results] A two-way analysis of variance detected an interaction between age and surface factors for anteroposterior acceleration at the center of mass of the head. For other body segments, interactions between the two factors were not detected. [Conclusion] The results of anteroposterior acceleration at the center of mass of the head suggest that under conditions of deteriorated somatosensory function in the lower limbs, minute anteroposterior position adjustment of the head is an essential characteristic of the standing posture control mechanism in the elderly.

Predictive potential of preoperative electroencephalogram for neuropsychological change following subthalamic nucleus deep brain stimulation in Parkinson's disease.

BACKGROUND: Deep brain stimulation of the bilateral subthalamic nucleus (STN-DBS) improves motor fluctuation and severe dyskinesia in advanced Parkinson's disease (PD). Effects on non-motor symptoms, such as neurocognitive side effects, can also influence the quality of life of both patients with PD and caregivers. Predictive quantitative factors associated with postoperative neurocognitive deterioration therefore warrant further attention. Here, we evaluated preoperative electroencephalogram (EEG) as a predictive marker for changes in neurocognitive functions after surgery. METHODS: Scalp EEG was recorded preoperatively from 17 patients with PD who underwent bilateral STN-DBS. Global relative power in the theta, alpha, and beta bands was calculated. Cognitive function was assessed with neuropsychological batteries preoperatively and 1 year after STN-DBS. RESULTS: Performance on the Symbol Search subtest of the WAIS III declined 1 year after DBS. The theta band was chosen for analysis with a 40% cutoff point for increased (≥ 40%) and decreased (< 40%) power. No significant differences between the two groups in baseline performance on most neuropsychological batteries were found, except for the Digit Symbol Coding subtest of the WAIS III. Changes in visual spatial functions were significantly different between groups. The increased theta band power group demonstrated a significant deterioration in performance on the WAIS III Matrix Reasoning subtest and the copy and immediate recall tasks of the Rey-Osterrieth complex figure test. CONCLUSIONS: These findings suggest that preoperative increases in theta power are related to postoperative deterioration of visuospatial function, which indicates the predictive potential of preoperative quantitative EEG for neurocognitive changes after STN-DBS.

Stretchable, adhesive and ultra-conformable elastomer thin films.

Thermoplastic elastomers are attractive materials because of the drastic changes in their physical properties above and below the glass transition temperature (Tg). In this paper, we report that free-standing polystyrene (PS, Tg: 100 °C) and polystyrene-polybutadiene-polystyrene triblock copolymer (SBS, Tg: -70 °C) thin films with a thickness of hundreds of nanometers were prepared by a gravure coating method. Among the mechanical properties of these thin films determined by bulge testing and tensile testing, the SBS thin films exhibited a much lower elastic modulus (ca. 0.045 GPa, 212 nm thickness) in comparison with the PS thin films (ca. 1.19 GPa, 217 nm thickness). The lower elastic modulus and lower thickness of the SBS thin films resulted in higher conformability and thus higher strength of adhesion to an uneven surface such as an artificial skin model with roughness (Ra = 10.6 µm), even though they both have similar surface energies. By analyzing the mechanical properties of the SBS thin films, the elastic modulus and thickness of the thin films were strongly correlated with their conformability to a rough surface, which thus led to a high adhesive strength. Therefore, the SBS thin films will be useful as coating layers for a variety of materials.

Focal calcium monitoring with targeted nanosensors at the cytosolic side of endoplasmic reticulum.

Ca2+ distribution is spatially and temporally non-uniform inside cells due to cellular compartmentalization. However, Ca2+ sensing with small organic dyes, such as fura-2 and fluo-4, has been practically applied at a single cell level where the averaged signal from freely diffusing dye molecules is acquired. In this study, we aimed to target azide-functionalized fura-2 (N3-fura-2) to a specific site of subcellular compartments to realize focal Ca2+ sensing. Using scAVD (single-chain avidin)-biotin interaction and a copper-free click reaction system, we linked N3-fura-2 to specifically-targeted scAVD protein fused with a red fluorescent protein mCherry, so that Ca2+ sensors conjugated with four N3-fura-2 dyes with dibenzocyclooctyne (DBCO)-PEG4-biotin as a linker were generated at subcellular compartments in living cells. In cytoplasm, N3-fura-2 showed a prolonged retention period after binding to scAVD. Furthermore, the reacted N3-fura-2 was retained inside cells even after free dyes were washed out by methanol fixation. When scAVD was overexpressed on endoplasmic reticulum (ER) membranes, N3-fura-2 was accumulated on ER membranes. Upon histamine stimulation, which increases cytosolic Ca2+ concentration, ER-localized N3-fura-2 successfully sensed the Ca2+ level changes at the cytosolic side of ER membrane. Our study demonstrated specific targeting of N3-fura-2 to subcellular compartments and the ability of sensing focal Ca2+ level changes with the specifically targeted Ca2+ sensors.

Reliability and validity of cough peak flow measurements in myasthenia gravis.

Decreased cough strength in myasthenia gravis (MG) leads to aspiration and increases the risk of MG crisis. The aim of this study was to clarify the reliability and validity of cough peak flow (CPF) measurements in MG. A total of 26 patients with MG who underwent CPF measurements using the peak flow meter by themselves were included. MG symptoms were evaluated by pulmonary function tests and clinical MG assessment scales before and after immune-treatments. The relationship between CPF and pulmonary function tests and MG comprehensive were assessed. The cut-off value of CPF for aspiration risk was determined and the area under the curve (AUC) was calculated. The intraclass correlation coefficient was more than 0.95 for pre-and post-treatment. Positive correlations were found between CPF and almost all spirometric values as well as between the differences of pre-and post-treatment in CPF and quantitative myasthenia gravis score. The CPF for identifying the aspiration risk was used to calculate the CPF cut-off value of 205 L/min with a sensitivity of 0.77, specificity of 0.90, and AUC of 0.85. The CPF, a convenient measure by patients themselves, has a high reliability in patients with MG, and is a useful biomarker reflecting MG symptoms.

Treatment with basic fibroblast growth factor-incorporated gelatin hydrogel does not exacerbate mechanical allodynia after spinal cord contusion injury in rats.

UNLABELLED: Besides stimulating angiogenesis or cell survival, basic fibroblast growth factor (bFGF) has the potential for protecting neurons in the injured spinal cord. OBJECTIVE: To investigate the effects of a sustained-release system of bFGF from gelatin hydrogel (GH) in a rat spinal cord contusion model. METHODS: Adult female Sprague-Dawley rats were subjected to a spinal cord contusion injury at the T10 vertebral level using an IH impactor (200 kdyn). One week after contusion, GH containing bFGF (20 µg) was injected into the lesion epicenter (bFGF - GH group). The GH-only group was designated as the control. Locomotor recovery was assessed over 9 weeks by Basso, Beattie, Bresnahan rating scale, along with inclined plane and Rota-rod testing. Sensory abnormalities in the hind paws of all the rats were evaluated at 5, 7, and 9 weeks. RESULTS: There were no significant differences in any of the motor assessments at any time point between the bFGF - GH group and the control GH group. The control GH group showed significantly more mechanical allodynia than did the group prior to injury. In contrast, the bFGF - GH group showed no statistically significant changes of mechanical withdrawal thresholds compared with pre-injury. CONCLUSION: Our findings suggest that bFGF-incorporated GH could have therapeutic potential for alleviating mechanical allodynia following spinal cord injury.

Postoperative Recovery of Gait Function at Early Phase Is Delayed in Patients with Spinal Tumors with Impairment of the Joint Position Sense in the Big Toe: A Retrospective Cohort Study.

Introduction: We investigated the effect of preoperative joint position sense in the big toe on the postoperative recovery of gait function after spinal tumor surgery. Methods: Seventy-three patients with spinal tumors who underwent surgery at our hospital between 2014 and 2019 and could be followed for at least 6 months after surgery were included. The patients were divided into the cervical spinal (41 cases) and thoracic spinal (32 cases) groups according to the localization of the tumor. These groups were further classified into an Impaired group (cervical spinal, 34 cases; thoracic spinal, 19 cases) and an Intact group (cervical spinal, 7 cases; thoracic spinal, 13 cases) according to the presence or absence of preoperative joint position sense in the big toe. The amount of change in ambulatory function from the preoperative period to 3 and 6 months postoperatively was compared between the Impaired and Intact groups within each tumor localization category. Results: Impaired preoperative joint position sense in the big toe in patients undergoing thoracic spinal tumor surgery delayed the recovery of gait function in the early postoperative period. Conclusions: In patients with thoracic spinal tumor surgery, the absence of preoperative joint position sense in the big toe delayed the recovery of postoperative gait function.

The third patient with Tsukahara-Azuno-Kaiji syndrome with type A1 brachydactyly, dwarfism, microcephaly, scoliosis, intellectual disability, ptosis, and hearing loss.

We report the case of the third patient with Tsukahara-Azuno-Kaiji syndrome. It is characterized by brachydactyly A1, dwarfism, microcephaly, scoliosis, intellectual disability, ptosis, and hearing loss. The first patient was reported in 1989, and the second in 2010. The present patient had many features in common with the previous 2 patients, with a few minor differences. Although this combination of symptoms is very characteristic, the clinicians should know about this syndrome to diagnose it. The syndrome in this patient appeared sporadically, and chromosome G-banding revealed a normal female karyotype of 46XX. However, further genetic research could not be performed. Steady accumulation of information will enable us to discover the true clinical and genetic nature of the disease and to make the diagnosis more easily.

Fluorescent "Turn-on" system utilizing a quencher-conjugated peptide for specific protein labeling of living cells.

A specific protein fluorescent labeling method has been used as a tool for bio-imaging in living cells. We developed a novel system of switching "fluorescent turn on" by the recognition of a fluorescent probe to a hexahistidine-tagged (His-tag) protein. The tetramethyl rhodamine bearing three nitrilotriacetic acids, which was used as a fluorescent probe to target a His-tagged protein, formed a reversible complex with the quencher, (Dabcyl)-conjugated oligohistidines, in the homogeneous solution, causing fluorescence of the fluorophore to be quenched. The complex when applied to living cells (COS-7) expressing His-tagged proteins on the cell surface caused the quencher-conjugated oligohistidines to be dissociated from the complex by specific binding of the fluorescent probe to the tagged protein, resulting in the fluorescent emission. The complex that did not participate in the binding event remained in the quenched state to maintain a low level of background fluorescence.

Dysfunction of the left angular gyrus may be associated with writing errors in ALS.

Background: Language dysfunction is a feature of cognitive impairment in amyotrophic lateral sclerosis (ALS) that may compromise communication. Objective: To elucidate language dysfunction in patients with ALS and its relationship with other neuropsychological tests and to identify the brain regions associated with this dysfunction using perfusion image. Methods: Overall, 37 patients with ALS were included in this study. Their neuropsychological function was investigated using the Western Aphasia Battery (WAB), Frontal Assessment Battery and Behavioral Assessment of the Dysexecutive Syndrome. N-isopropyl-p-[123I] iodoamphetamine single-photon emission computed tomography was used to examine regional cerebral blood flow and its relationship with WAB scores was investigated using multiple regression analyses, controlled for age, sex and years of education. Results: Frequency of language abnormality in ALS was 8.5% for spontaneous speech, 25.7% for auditory verbal comprehension, 8.8% for repetition, 14.7% for naming, 17.6% for reading and 51.4% for writing. The writing error was mainly omission and substitution of kana letters. Executive tests were correlated with naming (r > 0.5, p < 0.001) and reading (r > 0.4, p < 0.01) scores. With respect to the writing sub-test, positive perfusional relationship was only detected in the left angular gyrus. Conclusions: The left angular gyrus is the region associated with the writing errors observed in ALS.

Predicting Neurocognitive Change after Bilateral Deep Brain Stimulation of Subthalamic Nucleus for Parkinson's Disease.

OBJECTIVE: Deep brain stimulation (DBS) of the bilateral subthalamic nucleus (STN) is a standard surgical treatment option in patients with advanced Parkinson's disease. Adverse effects on cognitive function have been reported, impacting the quality of life of patients and caregivers. We aimed to investigate a quantitative predictive preexisting cognitive factor for predicting postoperative cognitive changes. METHODS: Thirty-five patients underwent STN-DBS. A battery of neuropsychological tests were used to examine executive function, processing speed, and visuospatial function both preoperatively and 1 year postoperatively. A multiple logistic regression analysis was performed to investigate the relationships between preoperative factors and cognitive outcomes. The predictive value of the preoperative factors for global cognitive decline during long-term follow-up were evaluated. RESULTS: The patients exhibited significant changes in processing speed and visuospatial function after surgery. Using reliable change index values, lower preoperative scores on the Similarities and Object Assembly subtests of the Wechsler Adult Intelligence Scale III were associated with decreases in visuospatial function at 1 year after DBS. The odds ratios were 10.2 for Similarities and 9.53 for Object Assembly. The proportion of Mini Mental State Examination-maintained patients with low scores on the Similarities subtest was significantly lower than that of patients with high scores at 3 and 5 years. No factors were found to be related to decreases in processing speed. CONCLUSIONS: Preoperative evaluation of the Similarities and Object Assembly subtests may be useful to identify patients who are at a greater risk of experiencing decreases in visuospatial functioning after STN-DBS. Furthermore, a low score on the Similarities subtest may predict future global cognitive deterioration.

Construction of a 'turn-on' fluorescent probe system for His-tagged proteins.

Hexahistidine ((His)(6)) tags are used to purify genetically engineered proteins. Herein, we describe the construction of a 'turn-on' fluorescent probe system that consists of the fluorescence quencher, Dabcyl, conjugated to (His)(6), and fluorescent tetramethylrhodamine conjugated to nitrilotriacetic acid, which, in the presence of Ni(2+), can bind (His)(6). The system is turned off when Dabcyl-(His)(6) is bound to the fluorescent nitrilotriacetic acid derivative. The binding strength of this system was assessed using electrospray ionization mass spectrometry, fluorescence correlation spectroscopy, and fluorescence intensity distribution analysis-polarization. Although there was no significant enhancement in fluorescence after addition of an equimolar amount of ubiquitin, the fluorescence increased from 14% to 40% of its initial intensity when an equimolar amount of (His)(6)-ubiquitin was added. Therefore, this system should be able to specifically recognize (His)(6)-proteins with good resolution and has the additional advantage that a washing step is not required to remove fluorescent probe, that is, not bound to the (His)(6)-protein.

Brain-derived neurotrophic factor suppresses anoikis-induced death of Schwann cells.

Anoikis is a type of apoptosis due to the detachment from the extracellular matrix and neighboring cells. In case of cell transplantation therapy for spinal cord injury, preparation of graft cells includes dissociation of cultured cells, which may cause anoikis-induced cell death. Thus suppression of anoikis may increase survival of grafted cells. Here we tested the effect of brain-derived neurotrophic factor (BDNF) on anoikis-induced cell death of cultured Schwann cells. Schwann cells were collected and cultured from sciatic nerves of neonatal Wistar rats. Schwann cells were plated upon a non-adherent polyhydroxyethyl methacrylate substrate to induce anoikis. BDNF was added into the culture medium at various concentrations. Twenty-four hours after non-adherent culture, approximately 40% of Schwann cells died and BDNF significantly decreased the number of dead cells in that culture condition. Next, Schwann cells were transplanted with or without BDNF treatment into contused rat spinal cord 1 week after injury. Five weeks after transplantation, immunohistochemistry revealed that the number of transplanted cells was significantly larger in the BDNF-treated group than that of the non-treated group. Suppression of anoikis may increase survival of grafted cells in case of cell therapy for spinal cord injury.

Photosensitized oxidation of nicotinamide adenine dinucleotide by diethoxyphosphorus(V)tetraphenylporphyrin and its fluorinated derivative: Possibility of chain reaction.

Water-soluble porphyrins, diethoxyphosphorus(V)tetraphenylporphyrin (EtP(V)TPP) and its fluorinated analogue (FEtP(V)TPP), decreased the typical absorption around 340nm of nicotinamide adenine dinucleotide (NADH) under visible light irradiation, indicating oxidative decomposition. A singlet oxygen quencher, sodium azide, and a triplet quencher, potassium iodide, slightly inhibited photosensitized NADH oxidation. However, these inhibitory effects were very small. Furthermore, the fluorescence lifetime of these P(V)porphyrins was decreased by NADH, suggesting the contribution of electron transfer to the singlet excited (S1) state of P(V)porphyrin. The redox potential measurement supports the electron transfer-mediated oxidation of NADH. The quantum yields of NADH photodecomposition by P(V)porphyrins could be estimated from the kinetic data and the effect of these quenchers on NADH oxidation. The obtained values suggest that the electron accepting by the S1 states of P(V)porphyrins triggers a chain reaction of NADH oxidation. This photosensitized reaction may play an important role in the photocytotoxicity of P(V)porphyrins. The axial ligand fluorination of P(V)porphyrins improved electron accepting ability. However, fluorination slightly suppressed static interaction with NADH, resulting in decreased oxidation quantum yield.

Short sleep duration, shift work, and actual days taken off work are predictive life-style risk factors for new-onset metabolic syndrome: a seven-year cohort study of 40,000 male workers.

BACKGROUND: This longitudinal study investigated the effects of various lifestyle-related factors - including sleep duration, shift work, and actual days taken off work - on new-onset metabolic syndrome (MetS). METHODS AND RESULTS: A total of 39,182 male employees (mean age 42.4 ± 9.8 years) of a local government organization in Japan were followed up for a maximum of seven years, between 1999 and 2006. Multivariate analysis (Cox proportional hazard method) identified seven high-risk lifestyle factors that were significantly associated with new-onset MetS or a range of metabolic factors (obesity, hypertension, hyperglycemia, dyslipidemia): (1) short sleep duration (<5 h/day), (2) shift work, (3) insufficient number of days off work, (4) always eating until satiety, (5) not trying to take every opportunity to walk, (6) alcohol intake ≥60 g/day, and (7) smoking. In addition, a higher number of these high-risk lifestyle factors significantly promoted the onset of MetS. The hazard ratio for MetS associated with 0-1 high-risk lifestyle parameters per subject at the baseline was set at 1.00. Hazard ratios associated with the following numbers of high-risk lifestyle parameters were: 1.22 (95% CI 1.15-1.29) for 2-3 of these parameters; and 1.43 (1.33-1.54) for 4-7. CONCLUSION: An increase in the number of high-risk lifestyle factors - such as short sleep duration, shift work, and an insufficient number of days off work - increased the risk of MetS onset. Comprehensive strategies to improve a range of lifestyle factors for workers, such as sleep duration and days off work, could reduce the risk of MetS onset.

Intrathecal Noggin administration in rats temporally ameliorates mechanical allodynia induced by a chronic constriction injury.

Chronic intractable neuropathic pain after central or peripheral nervous system injury remains refractory to therapeutic intervention. Using microarray and RT-qPCR methods, we found that Noggin mRNA is downregulated in the lumbar enlargement 2 weeks after chronic constriction injury (CCI) in rats. Eight-week-old female Sprague Dawley rats were used for the CCI model. Two weeks after CCI, rats underwent a laminectomy at L5 under halothane anesthesia, and a silicone tube connected to an osmotic minipump was inserted intrathecally for 14 days. Rats were administered Noggin ranging from 10 ng/ml to 10 µg/ml. Phosphate buffered saline (PBS) was used as a control. The time course of mechanical allodynia was assessed for 5 weeks using von Frey filaments. An ANOVA showed that rats administered Noggin at 2 µg/ml had significantly less mechanical allodynia compared with controls. We next compared the effect of intrathecal administration (14 days) of Noggin (2 µg/ml), bone morphogenetic protein 4 (BMP4; 2 µg/ml), or BMP4 (µg/ml) + Noggin (µg/ml) with controls. Only Noggin administration significantly reduced mechanical allodynia in the CCI model. Fluorescence immunohistochemistry indicated that Noggin administration decreased astrocyte accumulation in the dorsal horn compared with PBS after administration for one week. BMP4-driven conversion of oligodendrocyte progenitor cells (OPCs) to type 2 astrocytes is inhibited by Noggin Hampton et al. (2007) . We speculated that Noggin administration inhibits the conversion of OPCs to astrocytes, and decreases glial fibrillar acidic protein expression. This histological condition could decrease neuropathic pain.

A Cu-free clickable fluorescent probe for intracellular targeting of small biomolecules.

We synthesized a novel cyclooctyne-based clickable fluorescent probe with versatile properties such as high cell-membrane permeability and free diffusibility in the cell. Our probe "FC-DBCO" was conjugated to an azide-modified mannose via a Cu-free click reaction in living HeLa cells and displayed intracellular specific fluorescence imaging with low background signals.

A ratiometric fluorescent molecular probe for visualization of mitochondrial temperature in living cells.

Mitochondrial thermodynamics is the key to understand cellular activities related to homeostasis and energy balance. Here, we report the first ratiometric fluorescent molecular probe (Mito-RTP) that is selectively localized in the mitochondria and visualize the temperature. We confirmed that Mito-RTP could work as a ratiometric thermometer in a cuvette and living cells.

Effect of Laterally Wedged Insoles on the External Knee Adduction Moment across Different Reference Frames.

OBJECTIVE: Biomechanical effects of laterally wedged insoles are assessed by reduction in the knee adduction moment. However, the degree of reduction may vary depending on the reference frame with which it is calculated. The purpose of this study was to clarify the effect of reference frame on the reduction in the knee adduction moment by laterally wedged insoles. METHODS: Twenty-nine healthy participants performed gait trials with a laterally wedged insole and with a flat insole as a control. The knee adduction moment, including the first and second peaks and the angular impulse, were calculated using four different reference frames: the femoral frame, tibial frame, laboratory frame and the Joint Coordinate System. RESULTS: There were significant effects of reference frame on the knee adduction moment first and second peaks (P < 0.001 for both variables), while the effect was not significant for the angular impulse (P = 0.84). No significant interaction between the gait condition and reference frame was found in either of the knee adduction moment variables (P = 0.99 for all variables), indicating that the effects of laterally wedged insole on the knee adduction moments were similar across the four reference frames. On the other hand, the average percent changes ranged from 9% to 16% for the first peak, from 16% to 18% for the second peak and from 17% to 21% for the angular impulse when using the different reference frames. CONCLUSION: The effects of laterally wedged insole on the reduction in the knee adduction moment were similar across the reference frames. On the other hand, Researchers need to recognize that when the percent change was used as the parameter of the efficacy of laterally wedged insole, the choice of reference frame may influence the interpretation of how laterally wedged insoles affect the knee adduction moment.