Plantar intrinsic foot muscle activity and its relationship with postural sway during tiptoe standing in ballet dancers and non-dancers.

BACKGROUND: Minimizing postural sway during tiptoe standing is essential for ballet dancers. Investigation of the activity of the plantar intrinsic foot muscles (PIFMs) may provide insight into postural sway in dancers. Herein, we compared PIFM activity during tiptoe standing between dancers and non-dancers and examined its relationship with postural sway. METHODS: We enrolled 14 female ballet dancers and 13 female non-dancers. Electromyography (EMG) amplitudes of 64 channels of PIFMs and center of pressure (COP) data were recorded during bipedal tiptoe standing tasks performed with ankle plantarflexion angles of 20°, 40°, and 60° (dancers only). The EMG amplitudes were normalized to those during the maximum voluntary contraction, and the muscle activity level and its coefficient of variation over time (EMG-CVtime) during the task were assessed. Standard deviations in the anteroposterior and mediolateral directions, velocity, and area were calculated from the COP data. RESULTS: Most COP and EMG variables were significantly lower in dancers than in non-dancers in both the 20° and 40° tasks (p < 0.05). Significant correlations were found between most combinations of the COP and EMG variables in both the 20° and 40° tasks in the whole cohort (r = 0.468-0.807, p ≤ 0.014). In the 60° task in dancers, COP velocity was strongly correlated with EMG-CVtime (r = 0.700, p = 0.005). CONCLUSION: These results provide novel evidence that the PIFMs do not require high activity, but rather that its low, steady activity is the key, to achieve less postural sway during bipedal tiptoe standing in dancers.

Negative resistance state in superconducting NbSe2 induced by surface acoustic waves.

We report a negative resistance, namely, a voltage drop along the opposite direction of a current flow, in the superconducting gap of NbSe2 thin films under the irradiation of surface acoustic waves (SAWs). The amplitude of the negative resistance becomes larger by increasing the SAW power and decreasing temperature. As one possible scenario, we propose that soliton-antisoliton pairs in the charge density wave of NbSe2 modulated by the SAW serve as a time-dependent capacitance in the superconducting state, leading to the dc negative resistance. The present experimental result would provide a previously unexplored way to examine nonequilibrium manipulation of the superconductivity.

Publisher Correction: Autonomic versus perceptual accounts for tactile hypersensitivity in autism spectrum disorder.

A correction to this article has been published and is linked from the HTML version of this paper. The error has been fixed in the paper.

Autonomic versus perceptual accounts for tactile hypersensitivity in autism spectrum disorder.

Tactile atypicality in individuals with autism spectrum disorder (ASD) has harmful effects on their everyday lives including social interactions. However, whether tactile atypicality in ASD reflects perceptual and/or autonomic processes is unknown. Here, we show that adults with ASD have hypersensitivity to tactile stimuli in the autonomic but not perceptual domain. In particular, adults with ASD showed a greater skin conductance response (SCR) to tactile stimuli compared to typically developing (TD) adults, despite an absence of differences in subjective responses. Furthermore, the level of the SCR was correlated with sensory sensitivity in daily living. By contrast, in perceptual discriminative tasks that psychophysically measured thresholds to tactile stimuli, no differences were found between the ASD and TD groups. These results favor the hypothesis that atypical autonomic processing underlies tactile hypersensitivity in ASD.

Infant's action skill dynamically modulates parental action demonstration in the dyadic interaction.

When interacting with infants, human adults modify their behaviours in an exaggerated manner. Previous studies have demonstrated that infant-directed modification affects the infant's behaviour. However, little is known about how infant-directed modification is elicited during infant-parent interaction. We investigated whether and how the infant's behaviour affects the mother's action during an interaction. We recorded three-dimensional information of cup movements while mothers demonstrated a cup-nesting task during interaction with their infants aged 11 to 13 months. Analyses revealed that spatial characteristics of the mother's task demonstration clearly changed depending on the infant's object manipulation. In particular, the variance in the distance that the cup was moved decreased after the infant's cup nesting and increased after the infant's task-irrelevant manipulation (e.g. cup banging). This pattern was not observed for mothers with 6- to 8-month-olds, who do not have the fine motor skill to perform the action. These results indicate that the infant's action skill dynamically affects the infant-directed action and suggest that the mother is sensitive to the infant's potential to learn a novel action. A video abstract of this article can be viewed at: https://www.youtube.com/watch?v=VNS2IHwLIhg&feature=youtu.be.

Fourteen-month-old infants copy an action style accompanied by social-emotional cues.

Human adults exaggerate their actions and facial expressions when interacting with infants. These infant-directed modifications highlight certain aspects of action sequences and attract infants' attention. This study investigated whether social-emotional aspects of infant-directed modifications, such as smiling, eye contact, and onomatopoeic vocalization, influence infants' copying of another's action, especially action style, during the process of achieving an outcome. In Study 1, 14-month-old infants (n = 22) saw an experimenter demonstrate goal-directed actions in an exaggerated manner. Either the style or the end state of the actions was accompanied by social-emotional cues from the experimenter. Infants copied the style of the action more often when social-emotional cues accompanied the style than when they accompanied the end state. In Study 2, a different group of 14-month-old infants (n = 22) watched the same exaggerated actions as in Study 1, except that either the style or the end state was accompanied by a physical sound instead of social-emotional cues. The infants copied the end state consistently more often than the style. Taken together, these two studies showed that accompanying social-emotional cues provided by a demonstrator, but not accompanying physical sound, increased infants' copying of action style. These findings suggest that social-emotional cues facilitate efficient social learning through the adult-infant interaction.

Observation of self-binding in monolayer 3He.

We report clear experimental signatures of the theoretically unexpected gas-liquid transition in the first three monolayer systems of (3)He adsorbed on graphite. The transition is inferred from the linear density dependence of the gamma coefficient of the heat capacity measured in the degenerate region (2≤T≤80 mK) below a critical liquid density (ρ(c0)). Surprisingly, the measured ρ(c0) values (0.6-0.9 nm(-2)) are nearly the same for all these layers in spite of their quite different environments. We conclude that the ground state of (3)He in strictly two dimensions is not a dilute quantum gas but a self-bound quantum liquid with the lowest density ever found.

Localized distributions of quasi-two-dimensional electronic states near defects artificially created at graphite surfaces in magnetic fields.

We measured the local density of states of a quasi two-dimensional electron system (2DES) near defects, artificially created by Ar-ion sputtering, on surfaces of highly oriented pyrolytic graphite (HOPG) with scanning tunneling spectroscopy (STS) in high magnetic fields. At valley energies of the Landau level spectrum, we found two typical localized distributions of the 2DES depending on the defects. These are new types of distributions which are not observed in the previous STS work at the HOPG surface near a point defect [Y. Niimi, Phys. Rev. Lett. 97, 236804 (2006).10.1103/PhysRevLett.97.236804]. With increasing energy, we observed gradual transformation from the localized distributions to the extended ones as expected for the integer quantum Hall state. We show that the defect potential depth is responsible for the two localized distributions from comparison with theoretical calculations.

Construction of a versatile ultralow temperature scanning tunneling microscope.

We constructed a dilution-refrigerator (DR)-based ultralow temperature scanning tunneling microscope (ULT-STM) which works at temperatures down to 30 mK, in magnetic fields up to 6 T and in ultrahigh vacuum (UHV). Besides these extreme operation conditions, this STM has several unique features not available in other DR-based ULT-STMs. One can load STM tips as well as samples with clean surfaces prepared in an UHV environment to a STM head keeping low temperature and UHV conditions. After then, the system can be cooled back to near the base temperature within 3 h. Due to these capabilities, it has a variety of applications not only for cleavable materials but also for almost all conducting materials. The present ULT-STM has also an exceptionally high stability in the presence of magnetic field and even during field sweep. We describe details of its design, performance, and applications for low temperature physics.

[Epidemiologic examination on the prevalence of the periodontal diseases and oral pigmentation in Yusho patients in 2006].

An epidemiologic examination was carried out to reveal the prevalence of the periodontal diseases and oral pigmentation in patients with Yusho in 2006. The results obtained were as follows. (1) 98 patients out of 106 patients with Yusho, who were measured periodontal pocket depth according to Ramfjord' methods, had at least one tooth with periodontal pocket deeper than 3 mm. Similarly, 343 teeth out of a total 494 examined teeth showed periodontal pocket with more than 3 mm depth. (2) Oral pigmentation was observed in 61 patients out of 116 patients with Yusho. In this study, gingival pigmentation was most predominant among oral pigmentation. The prevalence of oral pigmentation in male patients seemed to be somewhat higher than that in female patients. In addition, this examination revealed that the patients below the age of sixty had a high prevalence of oral pigmentation. These results indicated that PCB-related compounds may be responsible for the higher prevalence of both periodontal diseases and oral pigmentation.

Application of ultrasonography for blunt laryngo-cervical-tracheal injury.

BACKGROUND: Bronchoscopy has been the gold standard for diagnosing blunt laryngo-cervical-tracheal injury (BLCTI); however, BLCTI is often undetected. Ultrasonography (US) is an indispensable tool in the field of critical care and traumatology, but has not been considered useful for evaluation of the airway. The aim of this study was to determine the usefulness of US in the diagnosis of BLCTI. METHODS: To determine the detectability of BLCTI by US, we use a model of cylindrical plastic with a protruding mass made of paste. The model was placed in a water bath and US (3.5-MHz probe) was used to try to detect the mass. RESULTS: We could detect the existence of the mass as a high echoic mass with strongly high echoic tail. We used four patients with BLCTIs whose sites of injury were confirmed by computed tomography (CT) and bronchoscopy. We evaluated the larynx and the cervical trachea as their outline of air in the cranial section near the sternal notch using a 3.5-MHz convex probe. The following US findings were compared with CT and bronchoscopic images as specific findings of BLCTI: discontinuity of the laryngo-cervical-tracheal wall and an abnormal mass protruding into the laryngo-cervical-tracheal lumen. Specific findings of BLCTI were detected in three of the four patients, whose sites of injury were the anterior or lateral side of the larynx or the cervical trachea. The site of injury of the remaining patient, where we detected no specific BLCTI findings, was the posterior wall of the larynx. CONCLUSIONS: US is useful for the diagnosis of BLCTI because it is capable of presenting specific images showing BLCTI features such as discontinuity of the laryngo-cervical-tracheal wall and abnormal masses protruding into the lumen; not only as a single diagnostic tool but one tool with many uses.

Reduced syndecan-1 expression is correlated with the histological grade of malignancy at the deep invasive front in oral squamous cell carcinoma.

BACKGROUND: Although many histopathological characteristics of oral squamous cell carcinoma (O-SCC) have been identified as prognostic factors, no factor is completely accurate and unequivocal. This study evaluated the association between the loss of syndecan-1 expression and the histological grade of malignancy at the deep invasive front in O-SCC. METHODS: The expression of syndecan-1 at the invasive tumor front of O-SCC was examined immunohistochemically using archived tissue from 72 cases. The mean age of the patients was 62.5 years (range: 23-90 years) and the male-female ratio was 1.3:1 (41 men, 31 women). There were 26, 24, 11, and 11 cases classified as stages I-IV respectively. The correlation between the intensity of syndecan-1 immunostaining and the clinicopathological factors, especially the histological grade of malignancy at the deep invasive front (invasive front grade) was analyzed. RESULTS: Of the 72 cases, seven (9.7%), 29 (40.3%), 36 (50.0%) showed strong, intermediate, and weak or negative syndecan-1 staining respectively. There were significant differences between syndecan-1 expression and prognosis, differentiation, and pattern of invasion at the deep invasive front. Moreover, the invasive front grade scores, based on the intensity of syndecan-1 staining, were 5.6 +/- 1.0, 8.0 +/- 2.1, and 10.2 +/- 2.3 points with strong, intermediate, and weak or negative intensity respectively; and the difference was significant (P < 0.0001). Patients with intermediate or strong intensity for syndecan-1 had significantly better prognoses than did those with negative or weak intensity (P = 0.0138). CONCLUSION: This study demonstrated that the reduced expression of syndecan-1 seems to be a useful marker of histological malignancy at the deep tumor invasive front and may be a useful prognostic factor in O-SCC.

Real-space imaging of alternate localization and extension of quasi-two-dimensional electronic States at graphite surfaces in magnetic fields.

We measured the local density of states (LDOS) of a quasi-two-dimensional (2D) electron system near point defects on a surface of highly oriented pyrolytic graphite with scanning tunneling microscopy and spectroscopy. Differential tunnel conductance images taken at very low temperatures and in high magnetic fields show a clear contrast between localized and extended spatial distributions of the LDOS at the valley and peak energies of the Landau level spectrum, respectively. The localized electronic state has a single circular distribution around the defects with a radius comparable to the magnetic length. The localized LDOS is in good agreement with a spatial distribution of a calculated wave function for a single electron in 2D in a Coulomb potential in magnetic fields.

The relationship of the histologic grade at the deep invasive front and the expression of Ki-67 antigen and p53 protein in oral squamous cell carcinoma.

BACKGROUND: Although many histopathologic characteristics of oral squamous cell carcinoma (O-SCC) have been identified as prognostic factors, accurate, and unequivocal factors have not been clearly identified. The purpose of this study was to evaluate a potential association between the histologic grade of malignancy at the deep invasive front and the expression of Ki-67 antigen and p53 protein in O-SCC. METHODS: The expression of Ki-67 antigen and p53 at the invasive tumor front area of O-SCC was examined by immunohistochemistry of archived tissue from 62 cases. The mean age of patients was 60.7 years (range: 37-89) and the male-female ratio was 1.6:1 (38 men, 24 women). There were 20, 17, 14, and 11 cases classified as stage I to stage IV, respectively. The correlation between the intensity of immunostaining for Ki-67 antigen and p53 and the histologic grade of malignancy at the deep invasive front (invasive front grade, IFG) was analyzed. The expression of Ki-67 antigen and p53 in normal oral epithelia (10 cases) was also investigated. RESULTS: The mean Ki-67 labeling index (LI) in the O-SCC samples was 32.8 +/- 12.0% (n = 62). The mean total score of IFG (IFG score) was 9.1 +/- 2.7 points (n = 62). There was a significant linear correlation between the IFG score and the Ki-67 antigen (gamma = 0.651, R2 = 0.596, P < 0.0001). Of 50 tumors examined, 27 (54.0%) exhibited p53-positive nuclear immunostaining. The staining patterns for Ki-67 antigen and p53 were similar. Both Ki-67-LI and p53-positive status were significantly correlated with the IFG scores. CONCLUSION: The findings of this study demonstrate that overexpression of Ki-67 antigen and p53 at the deep tumor invasive front of O-SCC is associated with histologic grade of malignancy.

STS observations of Landau levels at graphite surfaces.

Scanning tunneling spectroscopy (STS) measurements were made on surfaces of two different kinds of graphite samples, Kish graphite and highly oriented pyrolytic graphite (HOPG), at very low temperatures and in high magnetic fields. We observed a series of peaks in the tunnel spectra associated with Landau quantization of the quasi-two-dimensional electrons and holes. A comparison with the calculated local density of states at the surface layers allows us to identify Kish graphite as bulk graphite and HOPG as graphite with a finite thickness of 40 layers. This explains the qualitative difference between the two graphites reported in the recent transport measurements which suggested the quantum-Hall effect in HOPG. This work demonstrates how powerful the combined approach between the high quality STS measurement and the first-principles calculation is in material science.

Usefulness of the 3-dimensionally reconstructed computed tomography imaging for diagnosis of the site of tracheal injury (3D-tracheography).

Computed tomography (CT) has not been considered useful for early diagnosis of traumatized patients who could hardly hold their breath, particularly patients with tracheal injuries. However, the recent development of spiral CT has made it possible to acquire contiguous patient data, which eliminates the respiratory misregistration. Air is easily differentiated from surrounding tissues by striking contrast, and the trachea can therefore be well displayed by three-dimensional (3D)-CT. We consider that it is possible to show tracheal injury by 3D-CT. The aim of this study is to clarify the usefulness of 3D-CT for detecting the injury site of blunt tracheal injuries. The study was carried out in hemodynamically stable patients who were suspected of having tracheal injury based on clinical manifestations such as hemoptysis, or cervical subcutaneous, deep cervical, or mediastinal emphysema. Repeated bronchoscopy confirmed tracheal injury. The virtual images of the 3D-CT (3D-tracheography) were compared with the direct images of bronchoscopic findings. Five cases were examined. In patients with tracheal injury, bronchoscopy revealed laceration of the tracheal lumen or disruption and dislocation of the tracheal cartilage, partially coated by mucus and clot, findings that confirmed the diagnosis of tracheal injury. The virtual images of the 3D-tracheography clearly showed the injury as a defect in the tracheal wall or a depression in the wall. The site and size of injury shown in the 3D-tracheography were comparable with those detected by bronchoscopy. We succeeded in detecting tracheal injuries by 3D-CT imaging, the virtual images of which were comparable with the bronchoscopic findings. 3D-tracheography is a useful method for diagnosing the site and form of tracheal injury in hemodynamically stable patients.

Immunohistochemical study of syndecan-1 down-regulation and the expression of p53 protein or Ki-67 antigen in oral leukoplakia with or without epithelial dysplasia.

BACKGROUND: Leukoplakia is an oral pre-cancerous lesion that sometimes develops into squamous cell carcinoma. Therefore, leukoplakia with epithelial dysplasia is useful for studying carcinogenesis at the cellular level. The purpose of this study was to evaluate a potential association between the loss of syndecan-1 expression and the expression of p53 protein and Ki-67 antigen, and to identify reliable markers for predicting malignant changes in oral leukoplakia with epithelial dysplasia. METHODS: Changes in the expression of syndecan-1, p53, and Ki-67 were examined immunohistochemically in 43 cases of oral leukoplakia with or without epithelial dysplasia. The subjects were categorized as: none, 13 cases; mild dysplasia, 5 cases; moderate dysplasia, 17 cases; and severe dysplasia, 8 cases. The expression of these molecules in normal oral epithelia (22 cases) was also investigated. RESULTS: Strong syndecan-1 expression was observed on the surface of keratinocytes in normal epithelium. Immunopositivity was lost gradually as the extent of epithelial dysplasia increased. In normal epithelium, p53 and Ki-67 appeared mainly in the basal cell layer, while they were more widely distributed in leukoplakia. Specifically, significant changes were observed in the labeling index of p53 and Ki-67 in leukoplakia as epithelial dysplasia progressed from mild to moderate or severe. CONCLUSION: Our results reveal that overexpression of p53 protein and Ki-67 antigen, and down-regulation of syndecan-1 expression in the lower part of the epithelium, are associated with dysplastic changes. Therefore, the down-regulation of syndecan-1 expression may be the most important reliable marker for dysplastic changes.

An epidemiologic examination on the prevalence of the periodontal diseases and oral pigmentation in Yusho patients in 2002.

An epidemiologic examination was carried out to reveal the prevalence of the periodontal diseases and oral pigmentation in patients with Yusho. The results obtained were as follows. 1) 95 patients out of 110 patients, who were examined periodontal pocket depth using Ramfjord' methods, had at least one tooth with periodontal pocket deeper than 3 mm. Similarly, 276 teeth out of a total 495 examined teeth showed periodontal pockets with more than 3 mm depth. However, the ratio of the teeth with periodontal pockets deeper than 4 mm to total examined teeth in each age fell to less than 25%. 2) Oral pigmentation was observed in 75 patients out of 121 patients with Yusho. In this examination, gingival pigmentation was most predominant among oral pigmentation. It is of particular interest that severe pigmentation tended to be observed at a much higher frequency in younger patients with Yusho. Taken these findings into consideration, it was suggested that PCBs and related compounds might play an important role in the development of both periodontal diseases and oral pigmentation.

The reliability of the Bellhouse test for evaluating extension capacity of the occipitoatlantoaxial complex.

UNLABELLED: We examined the reliability of an airway evaluation test to assess the occipitoatlantoaxial (OAA) extension capacity described by Bellhouse et al. (Bellhouse test) in 20 adult volunteers with normal cervical spines. Each subject sat upright with the head in the neutral position and was then asked to extend the head maximally while attempting to move the neck as little as possible. The angle from the neutral position to the extreme extension was measured using the goggle-goniometer. Lateral cervical radiographs were taken in these positions, and the OAA extension angle was radiographically measured. Median values for OAA extension measured radiographically and extension of the head measured with the Bellhouse test were 21.5 degrees and 30 degrees, respectively. Extension of 9.5 degrees occurred at the subaxial regions, which could not be detected by inspecting surface contours of the neck. The extent of the subaxial extension was almost consistent with the degree of overestimation of the OAA extension capacity by the Bellhouse test. Because the subaxial extension occurred independent of the degree of the OAA extension, a strong relationship between the angle measured with the goggle-goniometer and the OAA extension angle measured radiographically was not established (P < 0.01, r(2) = 0.44). These findings mean that the test is not always accurate to evaluate the OAA extension capacity and will fail to detect a reduction of the OAA extension capacity if the subaxial regions are normal. Therefore, these problems derived from the Bellhouse test offer a potential for missing a prediction of difficult tracheal intubations because reduced OAA extension is one of the important factors that make intubation difficult. IMPLICATIONS: The Bellhouse test was not always accurate to evaluate the actual occipitoatlantoaxial extension capacity because of the inevitable occurrence of the subaxial extension. This may mean that some difficult endotracheal intubations will be unpredictable.

Risk factors for late cervical lymph node metastases in patients with stage I or II carcinoma of the tongue.

BACKGROUND: Many histopathologic parameters in squamous cell carcinoma of the tongue have been identified as predictive factors for cervical lymph metastasis. However, predictive factors for occult cervical lymph node metastases and the criterion for elective therapy remain inconclusive. This study analyzed the clinicopathologic factors associated with late cervical lymph node metastases in patients with carcinoma of the tongue. METHODS: The clinicopathologic features of 50 consecutive patients seen between January 1985-December 1996 with previously untreated stage I or II squamous cell carcinoma of the tongue were reviewed. All patients were treated with partial glossectomy without elective neck dissection. Their mean age was 54.5 y (range, 23-90 y) and the male-female ratio was 1.2:1 (27 men and 23 women); 30 cases were stage I, and 20 cases were stage II. Clinicopathologic factors were analyzed to determine factors predicting late cervical lymph node metastasis. RESULTS: The overall cervical lymph node metastasis rate was 14.0% (7 of 50). Clinicopathologic factors significantly associated with the development of cervical lymph node metastasis were tumor size (> or =30 mm), tumor depth (> or =4 mm), differentiation, mode of invasion, microvascular invasion, and histologic grade of malignancy. In a multivariate logistic regression analysis, moderately differentiated squamous cell carcinoma of the tongue with tumor depth > or =4 mm had predictive value for late cervical lymph node metastasis and diminished overall survival (odds ratio, 10.0; p =.02; hazards ratio, 7.0; p =.039). CONCLUSIONS: The findings of this study demonstrate tumor depth > or =4 mm moderately differentiated squamous cell carcinoma of the tongue have a substantially higher rate of late cervical metastases. In the basis of these data, it is our recommendation that this be used in the decision to electively treat the neck.