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1.
Surg Neurol Int ; 14: 76, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36895235

RESUMEN

Background: A previous report suggested that functional status does not differ between patients who received tranexamic acid and those who received placebo within the early hours of intracerebral hemorrhage (ICH). Our pilot study tested the hypothesis that 2 weeks administration of tranexamic acid would contribute to functional improvement. Methods: Consecutive patients with ICH were administered 250 mg tranexamic acid 3 times a day continuously for 2 weeks. We also enrolled historical control consecutive patients. We collected clinical data that involved hematoma size, level of consciousness, and Modified Rankin Scale (mRS) scores. Results: Univariate analysis showed that the mRS score on day 90 was better in the administration group (P = 0.0095). The mRS scores on the day of death or discharge suggested a favorable effect of the treatment (P = 0.0678). Multivariable logistic regression analysis also showed that the treatment was associated with good mRS scores on day 90 (odds ratio [OR] = 2.81, 95% confidence interval [CI]: 1.10-7.21, P = 0.0312). In contrast, ICH size was associated with poor mRS scores on day 90 (OR = 0.92, 95% CI: 0.88-0.97, P = 0.0005). After propensity score matching, there was no difference in the outcomes between the two groups. We did not detect mild and serious adverse events. Conclusion: The study could not show the significant effect of 2 weeks administration of tranexamic acid on functional outcomes of ICH patients after the matching; however, suggested that this treatment is at least safe and feasible. A larger and adequately powered trial is needed.

2.
Sports Biomech ; : 1-15, 2022 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-36510445

RESUMEN

This study was designed to develop a computational fluid dynamics (CFD) method for unsteady analysis of a series of ski jump movements with attitude changes, and to analyse the aerodynamic characteristics of an expert jumper over the entire ski jump movement. Two ski jumpers participated in this study. A sensor-based motion capture suit was used to capture the jumper's posture during the actual ski jump. A three-dimensional computer graphics animation was created by superimposing the joint angles obtained from the motion measurements of the 3D shape of the athlete. The unsteady aerodynamic forces acting on the ski jumper, from the takeoff to the landing, were then calculated using CFD. A time-varying spatially uniform flow was specified as the inflow boundary condition of the computational domain. The results indicated that both the lift and drag forces of the expert jumper increase rapidly during the initial flight when the jumper's posture changes drastically. Thereafter, drag force decreased considerably, but the decrease in the lift force was less drastic. Later in the flight phase, the lift force acting on the expert jumper increased, and throughout the flight phase, the lift-drag ratio of the expert jumper remained higher than that of the unskilled jumper.

3.
J Biochem ; 173(1): 21-30, 2022 Dec 27.
Artículo en Inglés | MEDLINE | ID: mdl-36174533

RESUMEN

IMP-type metallo-ß-lactamases confer resistance to carbapenems and a broad spectrum of ß-lactam antibiotics. IMP-6 and IMP-1 differ by only a point mutation: Ser262 in IMP-1 and Gly262 in IMP-6. The kcat/Km values of IMP-1 for imipenem and meropenem are nearly identical; however, for IMP-6, the kcat/Km for meropenem is 7-fold that for imipenem. In clinical practice, this may result in an ineffective therapeutic regimen and, consequently, in treatment failure. Here, we report the crystal structures of IMP-6 and IMP-1 with the same space group and similar cell constants at resolutions of 1.70 and 1.94 Å, respectively. The overall structures of IMP-6 and IMP-1 are similar. However, the loop region (residues 60-66), which participates in substrate binding, is more flexible in IMP-6 than in IMP-1. This difference in flexibility determines the substrate specificity of IMP-type metallo-ß-lactamases for imipenem and meropenem. The amino acid at position 262 alters the mobility of His263; this affects the flexibility of the loop via a hydrogen bond with Pro68, which plays the role of a hinge in IMP-type metallo-ß-lactamases. The substitution of Pro68 with a glycine elicited an increase in the Km of IMP-6 for imipenem, whereas the affinity for meropenem remained unchanged.


Asunto(s)
Imipenem , beta-Lactamasas , Meropenem , Especificidad por Sustrato , beta-Lactamasas/genética , beta-Lactamasas/química , beta-Lactamasas/metabolismo , Imipenem/farmacología , Carbapenémicos/farmacología , Antibacterianos/farmacología , Pruebas de Sensibilidad Microbiana
4.
BMC Sports Sci Med Rehabil ; 14(1): 71, 2022 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-35430808

RESUMEN

BACKGROUND: Use of a wearable gait analysis system (WGAS) is becoming common when conducting gait analysis studies due to its versatility. At the same time, its versatility raises a concern about its accuracy, because its calculations rely on assumptions embedded in its algorithms. The purpose of the present study was to validate twenty spatiotemporal gait parameters calculated by the WGAS by comparison with simultaneous measurements taken with an optical motion capture system (OMCS). METHODS: Ten young healthy volunteers wore two inertial sensors of the commercially available WGAS, Physilog®, on their feet and 23 markers for the OMCS on the lower part of the body. The participants performed at least three sets of 10-m walk tests at their self-paced speed in the laboratory equipped with 12 high-speed digital cameras with embedded force plates. To measure repeatability, all participants returned for a second day of testing within two weeks. RESULTS: Twenty gait parameters calculated by the WGAS had a significant correlation with the ones determined by the OMCS. Bland and Altman analysis showed that the between-device agreement for twenty gait parameters was within clinically acceptable limits. The validity of the gait parameters generated by the WGAS was found to be excellent except for two parameters, swing width and maximal heel clearance. The repeatability of the WGAS was excellent when measured between sessions. CONCLUSION: The present study showed that spatiotemporal gait parameters estimated by the WGAS were reasonably accurate and repeatable in healthy young adults, providing a scientific basis for applying this system to clinical studies.

5.
BMC Sports Sci Med Rehabil ; 14(1): 76, 2022 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-35484560

RESUMEN

BACKGROUND: A baseball pitcher with decreased scapular control may not be able to achieve suitable scapular motion at maximum shoulder external rotation (MER) of baseball pitching during the pitching action. It is common clinically to compare scapular control of the throwing and non-throwing arms to detect side-to-side differences. However, it remains unclear whether scapular control is different between the throwing and non-throwing arms. Moreover, no data exist on the relationship between scapular control and scapular motion at MER of pitching. Primarily, this study aimed to compare scapular control during isometric shoulder flexion between the throwing and non-throwing arms. Secondly, this study aimed to investigate the relationship between scapular control during isometric shoulder flexion and scapular motion at MER of pitching. METHODS: Fifteen healthy collegiate baseball pitchers (age, 20.2 ± 1.9 years; height, 1.76 ± 0.05 m; body mass, 73.3 ± 6.7 kg) were recruited. An optical motion tracking system was used to assess scapular motion. Scapular control was defined as the amount of change in the scapular internal rotation angle, downward rotation angle, and anterior tilt angle during isometric shoulder flexion. We assessed scapular position at MER of pitching. RESULTS: No significant differences were detected for any of the scapular angles during isometric shoulder flexion between the throwing and non-throwing arms. The amount of change in the scapular internal rotation angle, scapular downward rotation angle, and scapular anterior tilt angle during isometric shoulder flexion had a significant relationship with the scapular downward rotation angle at MER. CONCLUSIONS: No side-to-side difference was noted in scapular control during isometric shoulder flexion in healthy collegiate baseball pitchers at the group level. Further studies are required to understand the side-to-side differences at the individual level. Additionally, there was a relationship between scapular control during isometric shoulder flexion and scapular position at MER. These findings suggest that clinicians may consider using isometric shoulder flexion to assess scapular control in baseball pitchers.

7.
Cardiology ; 143(3-4): 92-99, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31330506

RESUMEN

BACKGROUND: There is wide variability of visit-to-visit (V2V) B-type natriuretic peptide (BNP) in patients with chronic heart failure (CHF), even when they are stable. The prognostic significance of V2V-BNP variability has not been investigated. We aimed to test whether V2V-BNP variability during the stable period of CHF has prognostic value regardless of BNP level. METHODS: In 278 stable outpatients (75 ± 10 years, 65% male) with CHF, we studied V2V-BNP variability, which was defined as the coefficient of variance of BNP values measured during 1 year before enrollment. All-cause death and rehospitalization due to HF were considered the primary endpoint. RESULTS: The median V2V-BNP variability was 25.7% (IQR: 19.2-34.4%). During the follow-up period (median 3.2 years), 100 patients reached the endpoint and those with high V2V-BNP variability (≥25.7%) had a significantly higher rate of events (p = 0.001). CHF severity in terms of BNP level and MAGGIC risk score was not significantly different between those with high and low V2V-BNP variability. Multivariable analysis showed that high V2V-BNP variability was independently associated with increased event rates even after adjustment for other known prognostic predictors, including BNP (hazard ratio 1.90, p = 0.003), or for MAGGIC risk score and BNP (hazard ratio 1.72, p = 0.010). The hazard for the outcome consistently increased as V2V-BNP variability increased, with a marked increase up to about 30%. CONCLUSIONS: Even in the stable phase of CHF, V2V-BNP variability was associated with worse long-term outcomes, independent of BNP level.


Asunto(s)
Insuficiencia Cardíaca/sangre , Péptido Natriurético Encefálico/sangre , Anciano , Anciano de 80 o más Años , Enfermedad Crónica , Femenino , Insuficiencia Cardíaca/diagnóstico , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos
8.
J Card Fail ; 25(9): 712-721, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30965102

RESUMEN

BACKGROUND: Prognostication of patients discharged after acute heart failure (AHF) hospitalization remains challenging. Body weight (BW) reduction is often used as a surrogate marker of decongestion despite the paucity of evidence. We thought to test the hypothesis that B-type natriuretic peptide (BNP) reduction during hospitalization has independent prognostic value in AHF. METHODS AND RESULTS: We studied the prognostic predictability of percentage BNP reduction achieved during hospitalization in patients from the REALITY-AHF study. Percentage BNP reduction was defined as (BNP on admission - BNP at discharge) / BNP on admission × 100. The primary endpoint was 1-year all-cause death. In 1028 patients (age, 77 ± 13 years; 57% male; left ventricular ejection fraction, 47 ± 16%) with AHF, median BNP level at admission was 747 ng/L (interquartile range, 439-1367 ng/L) and median percentage BNP reduction was 62.5% (interquartile range, 36.5-78.5%). The smallest percentage BNP reduction quartile had more than 2-fold higher risk of all-cause death than the greatest quartile (23.0% vs 9.7%, P< .001). After adjusting for covariates including BNP at discharge, the percentage BNP reduction was significantly associated with all-cause death (hazard ratio 0.96, 95% confidence interval 0.93-0.99, P= .032), whereas percentage BW reduction was not. Percentage BNP reduction was more predictive in patients with heart failure with reduced ejection fraction than in those with preserved ejection fraction. CONCLUSIONS: The prognostic value of percentage BNP reduction during hospitalization was superior to that of percentage BW reduction and was independent of other risk markers, including BNP at discharge.


Asunto(s)
Insuficiencia Cardíaca , Péptido Natriurético Encefálico/sangre , Enfermedad Aguda , Anciano , Biomarcadores/sangre , Peso Corporal , Femenino , Insuficiencia Cardíaca/sangre , Insuficiencia Cardíaca/diagnóstico , Insuficiencia Cardíaca/mortalidad , Insuficiencia Cardíaca/fisiopatología , Hospitalización/estadística & datos numéricos , Humanos , Japón/epidemiología , Masculino , Mortalidad , Alta del Paciente , Valor Predictivo de las Pruebas , Pronóstico , Sistema de Registros/estadística & datos numéricos , Medición de Riesgo/métodos , Volumen Sistólico
9.
Biochemistry ; 58(10): 1400-1410, 2019 03 12.
Artículo en Inglés | MEDLINE | ID: mdl-30789715

RESUMEN

Oxyhemoglobin (HbO2) coexisting with equimolar NADH retards autoxidation and oxidant-induced metHb formation based on the pseudocatalase (CAT) and pseudosuperoxide dismutase (SOD) activities. In this work, we compared the effects of NADH with those of NADPH and estimated the binding site of NAD(P)H to HbO2 to elucidate the antioxidative mechanisms. The results clarified that pseudo-CAT and pseudo-SOD activities of HbO2 coexisting with NADPH were similar to activities obtained with NADH. Prompt MetHb formation (<40 min) facilitated by oxidants (H2O2, NO, and NaNO2) was hindered by NADPH. These effects were similar to those of NADH. However, we found that NADPH is thermally unstable compared to NADH and that NADPH cannot sustain antioxidative effects for a long period of autoxidation to metHb such as 24 h. Lineweaver-Burk plots clarified that the Michaelis constants of these pseudoenzymatic activities are in the millimolar range. Addition of inositol hexaphosphate (IHP) and 2,3-diphosphoglycerate (DPG), which are known to bind not only with deoxyHb but also weakly with HbO2, showed competitive inhibition of pseudoenzymatic activities. These results suggest that the binding site of NADH and NADPH on HbO2 is the same as those of IHP and DPG. 31P nuclear magnetic resonance definitively showed 1:1 stoichiometric binding of NADH to HbO2. High-performance liquid chromatography analysis showed that NADH preferentially inhibited autoxidation of α-subunit heme. Docking simulations also predicted that the binding site of relaxed-state HbO2 with NAD(P)H is the same as those with IHP and DPG. Collectively, the pseudoenzymatic activities of HbO2 coexisting with NAD(P)H are induced by the 1:1 stoichiometric binding of NAD(P)H to HbO2.


Asunto(s)
Metahemoglobina/biosíntesis , NADP/metabolismo , Oxihemoglobinas/metabolismo , Antioxidantes/metabolismo , Sitios de Unión/genética , Catalasa/metabolismo , Hemoglobinas , Peróxido de Hidrógeno , Metahemoglobina/metabolismo , NAD/metabolismo , Oxidantes , Oxidación-Reducción , Superóxido Dismutasa/metabolismo
10.
Biomacromolecules ; 20(4): 1592-1602, 2019 04 08.
Artículo en Inglés | MEDLINE | ID: mdl-30715862

RESUMEN

Hemoglobin (Hb), an oxygen-carrying protein, has an α2ß2 tetrameric structure that dissociates reversibly into two αß dimers (α2ß2 ⇄ 2αß). We synthesized a cyclic Hb-ring monomer with two ß subunits bound through a 10 kDa polyethylene glycol (PEG) chain. The monomer induced ring-opening polymerization to produce a supramolecular polymer via intersubunit interaction of αß dimers of an Hb molecule at the PEG terminals. Both the ring-closed monomer and the ring-opened supramolecular polymer were then fixed covalently by intramolecular cross-linking of two ß subunits. Quantification of fixed products at various monomer concentrations revealed the equilibrium constant ( K), a ratio of propagation and depropagation rate constants, as 5.68 mM-1. The average degree of polymerization ([Formula: see text]) increased proportionally, concomitantly with the initial monomer concentration. Hb polymer with [Formula: see text] = 13.2 ( Mn = ca. 1 MDa) was obtained by cross-linking at 2.33 mM. Our novel strategy of ring-opening polymerization of Hb will eventually realize a highly aligned and efficiently polymerized Hb for creating artificial oxygen carriers for a clinical use.


Asunto(s)
Hemoglobinas/química , Polietilenglicoles/química , Polimerizacion , Humanos
11.
World Neurosurg ; 119: 394-399, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30096503

RESUMEN

BACKGROUND: Thyroid-stimulating hormone-secreting pituitary adenomas (TSHomas) are uncommon, and majority of the patients present with symptoms of hyperthyroidism. Herein, we report the first case of TSHoma with differentiated thyroid carcinoma (DTC) that presented with visual disturbance without any clinical feature of hyperthyroidism. CASE DESCRIPTION: A 57-year-old man presented with left temporal hemianopsia of his left eye without any sign of hyperthyroidism. A mass lesion in the sellar and suprasellar region compressing the optic nerves was identified via magnetic resonance imaging. Free thyroxine and free triiodothyronine levels were slightly elevated, whereas the serum level of thyroid-stimulating hormone remained within normal range. Further endocrinologic examination led to the preoperative diagnosis of TSHoma. Ultrasonography and 111In-octreotide scan showed a mass lesion in left lobe of the thyroid gland, and subsequent thyroid aspiration biopsy confirmed the diagnosis of papillary thyroid carcinoma. After administration of short-acting octreotide to prevent thyrotoxic crisis in the perioperative period, the tumor was removed via endoscopic transnasal-transsphenoidal surgery, and the pathologic diagnosis of TSHoma was made. His visual acuity improved, and free triiodothyronine and free thyroxine levels normalized. He underwent thyroidectomy 3 months later after endoscopic transnasal-transsphenoidal surgery. CONCLUSIONS: Herein, we report the first case of TSHoma with DTC that presented with visual disturbance without any clinical feature of hyperthyroidism and reviewed the 13 reported cases of TSHoma coexisting with DTC. The optimal treatment strategy in patients with TSHoma and coexistent DTC has not been established, and individualized therapeutic strategies are needed.


Asunto(s)
Adenoma/complicaciones , Neoplasias Hipofisarias/complicaciones , Cáncer Papilar Tiroideo/complicaciones , Tirotropina/metabolismo , Trastornos de la Visión/complicaciones , Adenoma/diagnóstico por imagen , Bases de Datos Bibliográficas/estadística & datos numéricos , Humanos , Hipertiroidismo/complicaciones , Antígeno Ki-67/metabolismo , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Neoplasias Hipofisarias/diagnóstico por imagen , Cáncer Papilar Tiroideo/diagnóstico por imagen , Trastornos de la Visión/diagnóstico por imagen
12.
Biomacromolecules ; 19(8): 3412-3420, 2018 08 13.
Artículo en Inglés | MEDLINE | ID: mdl-29952544

RESUMEN

Various chemical modifications of hemoglobin (Hb) including PEGylation have been investigated to produce red blood cell substitutes. Some of those modifications are designed on the premise that the α2ß2 tetrameric structure of Hb is fundamentally stable and that it rarely dissociates into two αß dimers in a physiological condition. However, in the present work using the "clipping" method we detected and quantitatively analyzed the considerable degree of exchange reaction of αß subunits between ß93Cys-bis-PEGylated and native Hbs through dissociation into αß dimers and restructuring to α2ß2 tetramer in a physiological condition. The equilibrium constant ( Keq) of subunit exchange reactions increased from 0.82 to 2.86 with increasing molecular weight of PEG from 2 to 40 kDa, indicating that longer PEG chains enhanced such exchange reaction. The results suggest that the exchange might occur for other modified Hbs even at a practically high concentration for use as a red blood cell substitute.


Asunto(s)
Hemoglobinas/química , Polietilenglicoles/química , Benzofuranos/química , Reactivos de Enlaces Cruzados/química , Ácidos Dicarboxílicos/química , Hemoglobinas/metabolismo , Humanos , Polietilenglicoles/metabolismo , Multimerización de Proteína , Subunidades de Proteína/química , Subunidades de Proteína/metabolismo
14.
Circ J ; 81(11): 1730-1735, 2017 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-28566643

RESUMEN

BACKGROUND: As mitral valve (MV) repair for Barlow's disease remains surgically challenging, it is important to distinguish Barlow's disease from fibroelastic deficiency (FED) preoperatively. We hypothesized that the prolapse volume to prolapse height ratio (PV-PH ratio) may be useful to differentiate Barlow's disease and FED.Methods and Results:In 76 patients with MV prolapse who underwent presurgical transesophageal echocardiography, the 3D MV morphology was quantified: 19 patients were diagnosed with Barlow's disease and 57 with FED. The patients with Barlow's disease had greater prolapse volume and height than the patients with FED, as well as greater PV-PH ratio (0.61±0.35 vs. 0.17±0.10, P<0.001). Receiver-operating characteristic analysis revealed that with a cutoff value of 0.27, the PV-PH ratio differentiated Barlow's disease from FED with 84.2% sensitivity and 84.2% specificity. Net reclassification improvement showed that the differentiating ability of the PV-PH ratio was significantly superior to prolapse volume (1.30, P<0.001). After being adjusted by each of prolapse volume and height, annular area and shape, and the number of prolapsed segments, the PV-PH ratio had an independent association with Barlow's disease. CONCLUSIONS: The PV-PH ratio was able to differentiate Barlow's disease from FED with high accuracy. 3D quantification including this value should be performed before MV repair.


Asunto(s)
Fibroelastosis Endocárdica/diagnóstico , Prolapso de la Válvula Mitral/diagnóstico , Adulto , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Persona de Mediana Edad , Prolapso de la Válvula Mitral/patología , Curva ROC , Sensibilidad y Especificidad
15.
Circ Cardiovasc Imaging ; 10(3)2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28289019

RESUMEN

BACKGROUND: The relationship between annular dilatation caused by atrial fibrillation (AF) and mitral regurgitation (MR) remains controversial. We hypothesized that the small ratio of total leaflet area/annulus area (TLA/AA), reflecting insufficient leaflet remodeling to annular dilatation, is a main component of MR in patients with AF. METHODS AND RESULTS: Three-dimensional transesophageal echocardiographic data of the mitral valve were analyzed in 28 AF patients with moderate or severe MR (MR group), age- and sex-matched 56 AF patients with mild or less MR (non-MR group), and 16 control subjects. AA was significantly greater in both the MR (645±126 mm2/m2, P<0.001) and non-MR groups (568±121 mm2/m2, P=0.001) compared with control subjects (444±108 mm2/m2). However, TLA/AA was significantly smaller in the MR (1.29±0.10, P<0.001), but not in the non-MR group (1.65±0.24, P>0.99), compared with control subjects (1.70±0.29). In linear regression analysis, TLA/AA was inversely associated with the effective regurgitant orifice (r=-0.73, P<0.001). The area under the receiver-operating-characteristics curve of TLA/AA was significantly greater than that of AA (0.95 versus 0.72, P<0.001). Multivariable analysis revealed that small TLA/AA (P<0.001) was independently associated with significant MR, while AA was not (P=0.26). CONCLUSIONS: In patients with AF, insufficient leaflet remodeling to annular dilatation, rather than crude annular dilatation, was strongly associated with the severity of MR.


Asunto(s)
Fibrilación Atrial/complicaciones , Función del Atrio Izquierdo , Remodelación Atrial , Insuficiencia de la Válvula Mitral/etiología , Válvula Mitral/fisiopatología , Anciano , Anciano de 80 o más Años , Área Bajo la Curva , Fibrilación Atrial/diagnóstico , Fibrilación Atrial/fisiopatología , Distribución de Chi-Cuadrado , Dilatación Patológica , Ecocardiografía Tridimensional , Ecocardiografía Transesofágica , Electrocardiografía , Femenino , Humanos , Japón , Modelos Lineales , Modelos Logísticos , Masculino , Persona de Mediana Edad , Válvula Mitral/diagnóstico por imagen , Insuficiencia de la Válvula Mitral/diagnóstico por imagen , Insuficiencia de la Válvula Mitral/fisiopatología , Análisis Multivariante , Valor Predictivo de las Pruebas , Pronóstico , Curva ROC , Estudios Retrospectivos , Factores de Riesgo , Índice de Severidad de la Enfermedad
16.
J Biomech ; 49(15): 3688-3696, 2016 11 07.
Artículo en Inglés | MEDLINE | ID: mdl-27743629

RESUMEN

The purpose of this study was to investigate the effects of posture of a ski jumper on aerodynamic characteristics during the take-off using computational fluid dynamics (CFD). The CFD method adopted for this study was based on Large-Eddy Simulation. Body surface data were obtained by 3-D laser scanning of an active ski jumper. Based on video analysis of the actual take-off movement, two sets of motion data were generated (world-class jumper A and less-experienced jumper B). The inlet flow velocity that corresponds to the in-run velocity in actual ski jumping was set to 23.23m/s in the CFD. The aerodynamic force, flow velocity, and vortexes for each model were compared between models. The total drag force acting upon jumper A was lower than that acting upon jumper B through the whole movement. Regarding the total lift force, although jumper A׳s total lift force was less in the in-run posture, it became greater than that of jumper B at the end of the movement. In the latter half of the movement, low air-speed domain expansion was observed at the model׳s back. This domain of jumper B was larger. There were two symmetric vortexes in the wake of jumper A, but the disordered vortexes were observed behind the jumper B. In the case of jumper A, these two distinct vortexes generated by the arms produced a downwash flow in the wake. It is considered that the positioning of the arms in a very low position strongly influences the flow structure.


Asunto(s)
Postura/fisiología , Esquí/fisiología , Adolescente , Adulto , Brazo/fisiología , Fenómenos Biomecánicos , Femenino , Humanos , Masculino , Modelos Teóricos , Movimiento/fisiología , Adulto Joven
17.
Echocardiography ; 33(5): 756-63, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26661528

RESUMEN

BACKGROUND: Previous studies indicated that the three-dimensional features of the mitral valve (MV) have a significant impact on MV disease. However, quantification of MV with manual tracing software was too time-consuming for routine clinical practice. This study was performed to investigate the efficacy and accuracy of MV quantification with a novel highly automated commercially available software package developed for this purpose. METHODS: Using the manual tracing and automated package, two expert sonographers and one cardiologist individually analyzed three-dimensional datasets acquired with transesophageal echocardiography from 74 patients (15 with functional mitral regurgitation, 32 with MV prolapse, and 27 normal subjects) retrospectively. Time for analysis and inter-observer agreement were compared between the two methods, and agreement of measurements was analyzed using Cronbach's α. RESULTS: Time for analysis using the automated package was significantly shorter than manual tracing (whole cohort, 260 ± 65 vs. 381 ± 68 seconds, P < 0.001; functional mitral regurgitation, 234 ± 42 vs. 378 ± 64 seconds, P < 0.001; MV prolapse, 293 ± 69 vs. 407 ± 67 seconds, P < 0.001; normal controls, 235 ± 52 vs. 351 ± 60 seconds, P < 0.001). There was good agreement among all three observers using both methods, and measurements with the automated package agreed well with the manual tracing values. CONCLUSIONS: The novel automated software package reduced time for quantification of MV with similar accuracy compared to the manual method. Automated quantification is useful and may be a key to widespread adoption of three-dimensional quantification in clinical practice.


Asunto(s)
Ecocardiografía Tridimensional/métodos , Ecocardiografía Transesofágica/métodos , Insuficiencia de la Válvula Mitral/diagnóstico por imagen , Prolapso de la Válvula Mitral/diagnóstico por imagen , Válvula Mitral/diagnóstico por imagen , Reconocimiento de Normas Patrones Automatizadas/métodos , Anciano , Algoritmos , Femenino , Humanos , Aumento de la Imagen/métodos , Interpretación de Imagen Asistida por Computador/métodos , Aprendizaje Automático , Masculino , Variaciones Dependientes del Observador , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
18.
J Phys Ther Sci ; 26(6): 833-9, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25013278

RESUMEN

[Purpose] This study investigated the characteristics of postural control following postural disturbance in elite athletes. [Subjects] Ten elite ski jumpers and ten control subjects participated in this study. [Methods] Subjects were required to maintain balance without stepping following unexpected horizontal surface perturbation in a forward or backward direction. [Results] A lower and reproducible peak magnitude of the center of mass velocity was shown in the athlete group compared to the control group. Cross-correlation analyses showed longer time lags at the moment of peak correlation coefficient between trunk flexor and extensor muscle activities, and shorter time lags and higher correlations between ankle flexor and extensor muscle activities were shown in the athlete group than in the control group. [Conclusion] The elite ski jumpers showed superior balance performance following surface perturbations, more reciprocal patterns in agonist-antagonist pairs of proximal postural muscles, and more co-contraction patterns in distal postural muscles during automatic postural responses than control individuals. This strategy may be useful in sports requiring effective balance recovery in environments with a dynamically changing surface, as well as in rehabilitation.

19.
EuroIntervention ; 9(9): 1050-6, 2014 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-24457276

RESUMEN

AIMS: Nicorandil, an ATP sensitive potassium channel opener, may reduce the incidence of microvascular dysfunction after percutaneous coronary intervention (PCI) by dilating coronary resistance vessels. The aim of the study was evaluation of the impact of the administration of intravenous nicorandil on measuring the index of microcirculatory resistance (IMR) in PCI to patients with stable angina pectoris (SAP). METHODS AND RESULTS: Intravascular ultrasound (IVUS), fractional flow reserve (FFR), IMR and blood examination (CK-MB), cardiac troponin I (cTnI) immediately post-PCI (and 24 hours later) were performed in 62 consecutive patients with SAP undergoing PCI. FFR and IMR were measured simultaneously with a single coronary pressure wire. IMR was defined as Pd/coronary flow (or Pd* mean transit time) at peak hyperaemia. Patients were randomised to the control (n=29), or nicorandil group (n=33). In the nicorandil group, nicorandil was intravenously administered as a 6 mg bolus injection just before PCI and as a constant infusion at 6 mg/hour for 24 hours thereafter. All volumetric IVUS parameters and FFR were similar between the two groups both pre- and post-PCI. However, IMR immediately post-PCI and cTnI 24 hours post-PCI were significantly higher in the control group compared to the nicorandil group (IMR: 25.4±12.1 vs. 17.9±9.1 units, and cTnI: 0.21±0.13 vs. 0.12±0.08 ng/mL, for control vs. nicorandil). The incidence for cTnI elevation more than fivefold the normal range (>0.20 ng/mL) was significantly larger in the control group than in the nicorandil group (41% vs. 12%, p<0.01). Additionally, the control group showed a closer correlation between plaque volume reduction during stenting as assessed by volumetric IVUS, and cTnI elevation than the nicorandil group (r=0.55 vs. 0.42, p<0.001 for control vs. nicorandil). CONCLUSIONS: In patients undergoing successful coronary stenting for stable angina, administration of nicorandil is associated with reduced microvascular dysfunction induced by PCI.


Asunto(s)
Angina Estable/cirugía , Antihipertensivos/uso terapéutico , Circulación Coronaria/efectos de los fármacos , Microcirculación/efectos de los fármacos , Nicorandil/uso terapéutico , Intervención Coronaria Percutánea , Resistencia Vascular/efectos de los fármacos , Anciano , Anciano de 80 o más Años , Angina de Pecho/complicaciones , Angina de Pecho/tratamiento farmacológico , Antihipertensivos/administración & dosificación , Vasos Coronarios/efectos de los fármacos , Vasos Coronarios/cirugía , Femenino , Humanos , Masculino , Microcirculación/fisiología , Persona de Mediana Edad , Nicorandil/administración & dosificación , Intervención Coronaria Percutánea/métodos , Stents , Resultado del Tratamiento
20.
Heart Vessels ; 29(2): 178-85, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23563752

RESUMEN

The OLmesartan on the progression of coronary atherosclerosis: evaluation by IntraVascular UltraSound (OLIVUS) trial demonstrated that an angiotensin II receptor blocker, olmesartan, reduces the rate of coronary atheroma progression as evaluated by intravascular ultrasound in patients with stable angina pectoris undergoing percutaneous coronary intervention. This substudy examined the impact of olmesartan on serum biomarkers and the relationship between biomarker changes and atheroma progression. Patients in the OLIVUS trial (n = 247) were randomly assigned to a control group or the olmesartan group. A subgroup of these patients (n = 135, 55 %) was analyzed at baseline and at 14 months. Patients' characteristics and blood-pressure control were identical between the control group (n = 65) and the olmesartan group (n = 70), and also between the subpopulation and total population. The change in the level of high-sensitivity C-reactive protein (hs-CRP) (mg/l) and adiponectin (µg/ml) was significantly greater in the olmesartan group than in the control group (between-group differences: 0.5 and -0.7; 95 % confidence interval: 0.2-0.8 and -1.3 to -0.1; P = 0.001 and 0.02, respectively). Multiple regression analysis revealed that the nominal changes in total atheroma volume and percent atheroma volume were significantly associated with the nominal change in hs-CRP in the olmesartan group but not in the control group. Olmesartan reduced hs-CRP in patients with stable angina, and this correlated with the change in coronary atheroma.


Asunto(s)
Angina Estable/terapia , Bloqueadores del Receptor Tipo 1 de Angiotensina II/uso terapéutico , Antiinflamatorios/uso terapéutico , Enfermedad de la Arteria Coronaria/terapia , Vasos Coronarios/efectos de los fármacos , Imidazoles/uso terapéutico , Mediadores de Inflamación/sangre , Intervención Coronaria Percutánea , Tetrazoles/uso terapéutico , Adiponectina/sangre , Anciano , Angina Estable/sangre , Angina Estable/diagnóstico , Biomarcadores/sangre , Proteína C-Reactiva/metabolismo , Enfermedad de la Arteria Coronaria/sangre , Enfermedad de la Arteria Coronaria/diagnóstico , Vasos Coronarios/metabolismo , Vasos Coronarios/ultraestructura , Progresión de la Enfermedad , Regulación hacia Abajo , Femenino , Humanos , Japón , Masculino , Persona de Mediana Edad , Placa Aterosclerótica , Estudios Prospectivos , Factores de Tiempo , Resultado del Tratamiento , Ultrasonografía Intervencional
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