Laterality in Body Coordination of Professional and Amateur Ballet Dancers While Performing a Single Pirouette with Pointe Shoes.

OBJECTIVE: Imbalances in muscle strength coordination owing to lateral preference may be a risk factor for injury in dancers. Postural control is essential for the basic turn in ballet (pirouette), owing to its lateral asymmetry. Since dance with pointe shoes demands greater range of motion, muscle strength, and balance control compared to dancing with flat shoes, pointe shoes may further add to the risk and cause an imbalance between the preferred and non-preferred legs during pirouette. In this study, we examined lateral differences in professional and experienced amateur ballet dancers during single pirouettes with pointe shoes to understand the multiple elements involved in lateral balance control in pirouettes. METHODS: Eight female professionals and seven female amateur ballet dancers performed single pirouettes in pointe shoes on both the preferred and non-preferred sides. To understand the body coordination laterality in single pirouettes, statistical parametric mapping was performed for the trunk, hip, knee, ankle angle, and center of mass-center of pressure inclination angle timeframe data during the pirouette in three phases: turn with double-leg (Phase 1), single-leg (Phase 2), and finish turning with a single-leg (Phase 3). In addition, the hop-up time was calculated as the percentage when the foot is not in contact with the ground in Phases 2 and 3. RESULTS: There were no lateral differences in trunk and lower limb angles in either group. Professional dancers showed slightly more inclination towards the stance leg during left rotation at the beginning of the movement (Phase 1) with longer hop-up time in Phase 2, whereas amateur dancers tended to tilt forward during the left turn (Phases 1 and 2) with longer hop-up time in Phase 3. CONCLUSION: It is notable that the COP-COM inclination angle was adjusted by hop-up and it caused the lateral differences in both professional and amateur dancers during a single pirouette with pointe shoes. This study highlights elements to consider in laterality when monitoring pirouette performance with pointe shoes.

Differences in the Rotation Axis Between Professional and Experienced Amateur Ballet Dancers During pirouette en dehour in Classical Ballet With Wearing Pointe Shoes: A Pilot Study.

Introduction: En pointe, in which weight is placed on the tiptoes, is a fundamental practice for female ballet dancers with pointe shoes. The center of mass (COM) is maintained over the base of support and the relative position of COM to the center of pressure (COP) is especially important when conducting a pirouette in ballet. A pirouette is a fundamental turn in classical ballet with flat shoes and pointe shoes. The investigation of the turn with pointe shoes would be favorable for understanding the movement with limited base of support. Herein, we aimed to determine the differences in the ability to perform pirouettes with pointe shoes between professional and amateur ballet dancers. Methods: This study included 8 professional and 9 amateur ballet dancers. The dancers performed a single pirouette, and the movement was captured and analyzed in 3 phases: turning with double-leg support (TDS), turning with single-leg support in pre-swing (TSSp), and turning with single-leg support in mid-swing (TSSm). The analysis focused on the inclination between the vertical angle and the COP-COM line, the vertical maximum reaction force, and the jump-up time in each phase. Results: The results showed no significant differences between the TDS and TSSp. However, professional ballet dancers exhibited significantly lesser posterior inclinations (professional; 2.05° ± 0.90°, amateur; 3.88° ± 1.67°) and jump-up time (professional; 0%, amateur; 1.4% ± 1.3%) than amateur dancers during TSSm. Conclusion: Overall, the findings suggest that professional dancers exhibit superior control skills regarding the COP-COM line than amateur dancers during TSSm. These results may be attributed to the fact that professional dancers can maintain the COM as close to the upright as on the COP without jumping during TSSm. This enables professional dancers to conduct the movements esthetically and continue on to the other movements in the dance phase.

Rotational Movement of the Upper Limbs Associated with the Aesthetic Appreciation of Ballet.

OBJECTIVE: This study aimed to identify the structure of upper limb movements in ballet dancers that affect the audience's perception of the aesthetics and to examine if upper limb rotational movement is a factor contributing to the aesthetics of ballet. METHODS: This study comprised 3-dimensional movement analysis and subjective evaluation of 12 female ballet dancers. Thirty-three reflective markers were affixed to their bodies. Their upper limb movements, which are bodily expressions mimicking a swan's flapping movement, were captured and viewed by 34 observers with previous ballet experience (i.e., university students majoring in dance education). The joint angle and velocity of each body part were calculated from the coordinates of the markers. The observers subjectively evaluated the videos through four pairs of categories: "beautiful-ugly," "like-dislike," "interesting-not interesting," and "good-bad," on a five-point semantic differential scale. Two groups were extracted based on the "beautiful-ugly" rating and compared using an independent t-test. An exploratory factor analysis was performed on the kinematic parameters that showed significant differences. RESULTS: Five factors were identified: amplitude of rotational movement, speed of upward arm movement, amplitude of movement in the distal upper limbs, apparent speed of the downward arm movement, and speed of the internal rotation movement. CONCLUSION: The results sup¬ported the hypothesis that rotational movement of the upper limbs is a factor contributing to the aesthetics of upper limb movements in ballet and will be useful for understanding the intrinsic aesthetics of upper limb movements in ballet.

Both Upper and Lower Limb Movements Contribute to Aesthetics of the Piqué Arabesque in Ballet.

This study aimed to identify the factor structures-which are the predominant frameworks for describing the basic dimensions of a concept-that contribute to the aesthetics of body position in ballet. This study was composed of three-dimensional movement analysis and subjective evaluation. Fourteen ballet dancers participated in the three-dimensional movement analysis. Thirty-six reflective markers were attached to the dancers' bodies, after which the dancers performed a piqué arabesque, a position in which the weight transfers from one leg to the other. This movement was captured using eight optical cameras and one video camera. Biomechanical parameters, such as the joint angle and velocity of each body part, were calculated from the coordinates of the markers. Twenty-eight videos recorded in the three-dimensional movement analysis were viewed by 51 observers with ballet experience. The observers subjectively evaluated the videos through four category pairs-"beautiful-ugly," "like-dislike," "interesting-not interesting," and "good-bad"-on a five-point semantic differential scale. Two groups, the top and bottom 30%, were extracted based on the "beautiful-ugly" rating and compared using an independent t-test. In addition, exploratory factor analysis was performed on the biomechanical parameters that showed significant differences. Five factors were identified: "stability of the right distal upper limb and upper body," "torso displacement speed," "stability of the left distal upper limb and line of the support leg," "height of the gesture leg," and "stability of the support leg around the hip joint and line of the limbs on the gesture leg side." These results indicate that the movements of both upper and lower limbs contributed to the aesthetics of the ballet position of piqué arabesque. These findings will be useful for ballet teachers and dancers to understand the intrinsic aesthetics of movements.

Silk sericin intake leads to increases in L-serine and L-tyrosine levels in the mouse brain and the simultaneous facilitation of brain noradrenergic turnover.

Sericin is a protein component of the silkworm cocoon, and contains a high proportion of L-serine, but it has been mostly disposed of as an industrial waste. However, recent studies have revealed its unique biological functionalities beneficial to human health. This study aimed to evaluate the effect of acute oral intake of sericin on amino acid and neurotransmitter metabolism in the mouse brain. Acute administration of chemically modified sericin (0.26 g/30 g body weight) increased L-serine and L-tyrosine levels in the serum and brain, although the L-tyrosine content in the sericin was less than 3% (w/w). In addition, sericin administration led to a significant facilitation of noradrenergic turnover via enhancement of 3-methoxy-4-hydroxyphenylethyleneglycol, a principal metabolite of noradrenaline, in several of the brain regions examined. These present findings suggest that oral intake of sericin efficiently delivers L-serine and L-tyrosine to the brain, thus stimulating noradrenergic activity in the brain.Abbreviations: DA: dopamine; 5-HIAA: 5-hydroxyindoleicetic acid; 5-HT: 5-hydroxytryptamine; HVA: homovanillic acid; MHPG: 3-methoxy-4-hydroxyphenylethyleneglycol; 3-MT: 3-methoxytyramine; NA: noradrenaline; NM: normetanephrine; Veh: vehicle.

Intra- and Inter-individual Movement Variability of Upper Limb Movements of Ballet Dancers.

OBJECTIVE: This study examined intra- and inter-individual variability in upper limb movements of ballet dancers when performing flapping swan-wing movements, and it assessed differences in joint angles of upper limbs between dancers of different skill levels. METHODS: 23 female ballet dancers (3 professional, 6 advanced, and 14 intermediate dancers) and 21 age-matched females without previous dance experience participated in this study. Thirty-three reflective markers were attached to each participant's trunk and upper limbs, and the flapping upper limb motions from Swan Lake were subsequently captured with eight optical cameras. Peak values of upper limb joint angles (shoulder, elbow, and wrist joint) were obtained, and intra- and inter-individual movement variability of each joint angle were compared between groups. RESULTS: In joint angles of the shoulder, elbow, and wrist, there were few differences among professional, advanced, and intermediate groups. The intra-individual movement variability in upward arm movements was significantly larger for professional and control groups than for advanced and intermediate groups, while in downward arm movement, variability became significantly smaller as technical level increased. Moreover, inter-individual movement variability was larger in the upward arm movement as technical level increased, and smaller in the downward arm movement for the professional group. The results suggested that the upward arm movements reflect dancers' individual expression, while the downward arm movements reflect their technical competence at this swan-like movement. CONCLUSION: The complicated swan-like movements performed by skilled dancers in this study indicate that they execute expressive and technical components in sequence.

Enhanced vulnerability to oxidative stress and induction of inflammatory gene expression in 3-phosphoglycerate dehydrogenase-deficient fibroblasts.

l-Serine (l-Ser) is a necessary precursor for the synthesis of proteins, lipids, glycine, cysteine, d-serine, and tetrahydrofolate metabolites. Low l-Ser availability activates stress responses and cell death; however, the underlying molecular mechanisms remain unclear. l-Ser is synthesized de novo from 3-phosphoglycerate with 3-phosphoglycerate dehydrogenase (Phgdh) catalyzing the first reaction step. Here, we show that l-Ser depletion raises intracellular H2O2 levels and enhances vulnerability to oxidative stress in Phgdh-deficient mouse embryonic fibroblasts. These changes were associated with reduced total glutathione levels. Moreover, levels of the inflammatory markers thioredoxin-interacting protein and prostaglandin-endoperoxide synthase 2 were upregulated under l-Ser-depleted conditions; this was suppressed by the addition of N-acetyl-l-cysteine. Thus, intracellular l-Ser deficiency triggers an inflammatory response via increased oxidative stress, and de novo l-Ser synthesis suppresses oxidative stress damage and inflammation when the external l-Ser supply is restricted.

Disorganized Steroidogenesis in Adrenocortical Carcinoma, a Case Study.

Most adrenocortical carcinomas (ACCs) produce excessive amounts of steroid hormones including aldosterone, cortisol, and steroid precursors. However, aldosterone- and cortisol-producing cells in ACCs have not yet been immunohistochemically described. We present a case of ACC causing mild primary aldosteronism and subclinical Cushing's syndrome. Removal of the tumor cured both conditions. In order to examine the expression patterns of the steroidogenic enzymes responsible for adrenocortical hormone production, 10 tumor portions were immunohistochemically analyzed for aldosterone synthase (CYP11B2), 11ß-hydroxylase (CYP11B1, cortisol-synthesizing enzyme), 3ß-hydroxysteroid dehydrogenase (3ßHSD, upstream enzyme for both CYP11B2 and CYP11B1), and 17α-hydroxylase/C17-20 lyase (CYP17, upstream enzyme for CYP11B1, but not for CYP11B1). CYP11B2, CYP11B1, and 3ßHSD were expressed sporadically, and their expression patterns varied significantly among the different tumor portions examined. The expression of these enzymes was random and not associated with each other. CYP17 was expressed throughout the tumor, even in CYP11B2-positive cells. Small tumor cell populations were aldosterone- or cortisol-producing cells, as judged by 3ßHSD coinciding with either CYP11B2 or CYP11B1, respectively. These results suggest that the tumor produced limited amounts of aldosterone and cortisol due to the lack of the coordinated expression of steroidogenic enzymes, which led to mild clinical expression in this case. We delineated the expression patterns of steroidogenic enzymes in ACC. The coordinated expression of steroidogenic enzymes in normal and adenoma cells was disturbed in ACC cells, resulting in the inefficient production of steroid hormones in relation to the large tumor volume.

Evanescent Hyperechoic Changes After Fine-Needle Aspiration Biopsy of the Thyroid in a Series With a Low Overall Prevalence of Complications.

OBJECTIVES: The purpose of this study was to assess the frequency of and risk factors for fine-needle aspiration biopsy (FNAB)-related complications in Japanese patients with thyroid nodules evaluated by standard FNAB techniques. METHODS: Six hundred fifty-three consecutive Japanese patients with 742 nodules who had undergone FNAB were enrolled. Nodule characteristics were evaluated, and thyroid volumes were measured. Fine-needle aspiration biopsy-related complications were identified on the basis of sonographic findings and patients' conditions after undergoing FNAB. Comparisons of patients' backgrounds and nodule characteristics were made between those with and without complications. RESULTS: The prevalence rates for FNAB-related complications, including acute transient thyroid swelling after FNAB and appearance of anechoic lesions, were 0.13% and 0.94%. In this study, we could not identify risk factors for FNAB-related complications. The sudden appearance of bright hyperechoic foci within the thyroid immediately after biopsy was reported as an FNAB-related unfamiliar appearance in 5 cases. Experimental FNA using resected porcine thyroid tissue suggested that the etiology of the hyperechoic appearance may be artificial air bubbles or reversed flow of aspirated fluid. CONCLUSIONS: Fine-needle aspiration biopsy-related complications are rare if preventive measures are performed and are not specific to Japanese patients with thyroid nodules. The sudden appearance of bright hyperechoic foci may be cause by contamination from air or fluid.

Cutoff value of thyroid uptake of (99m)Tc-pertechnetate to discriminate between Graves' disease and painless thyroiditis: a single center retrospective study.

Thyroid uptake of (99m)Tc-pertechnetate is a useful way to determine the cause of thyrotoxicosis. In daily clinical practice, (99m)Tc-pertechnetate uptake is used to discriminate between Graves' disease and painless thyroiditis when clinical information is not enough to make the distinction. However, since the optimal cutoff value of (99m)Tc-pertechnetate uptake has not yet been elucidated, our aim was to determine this value. We recruited patients with thyrotoxicosis in whom (99m)Tc-pertechnetate uptake was measured in clinical settings between 2009 and 2013. Three experienced endocrinologists (who were blinded to the value of (99m)Tc-pertechnetate uptake and initial treatment) diagnosed the cause of thyrotoxicosis based on thyrotropin, free triiodothyronine, free thyroxine, and thyrotropin receptor antibody levels, and by ultrasound findings and using images of thyroid uptake of (99m)Tc-pertechnetate without the actual values. Ninety-four patients diagnosed as having Graves' disease or painless thyroiditis were finally included. According to the diagnosis, the optimal cutoff value of (99m)Tc-pertechnetate uptake was determined by receiver operating characteristics analysis. A cutoff value of 1.0% provided optimal sensitivity and specificity of 96.6% and 97.1%, respectively. Then, its validity was confirmed in 78 patients with confirmed Graves' disease or painless thyroiditis diagnosed at another institute. Applying this cutoff value to the patients with thyrotoxicosis revealed positive and negative predictive values for Graves' disease of 100% and 88.9%, respectively. In conclusion, a cutoff value for (99m)Tc-pertechnetate uptake of 1.0% was useful to discriminate between Graves' disease and painless thyroiditis.