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1.
Sports (Basel) ; 10(2)2022 Feb 06.
Article in English | MEDLINE | ID: mdl-35202060

ABSTRACT

In baseball, the swing speed and swing angle of the bat just before ball impact are important to increase the speed and horizontal distance of a batted ball. This study investigated the accuracies and error trends of four commercially available bat sensors to measure these parameters. The hitting motions of seven healthy participants were measured simultaneously using the bat sensors and an optical motion capture system, and the swing speeds and swing angles were compared. The swing speed was measured with high accuracy, as indicated by the high intraclass correlation coefficient (ICC) between the bat sensor and the motion capture system measurements (mean ICC = 0.78). However, the ICC for the swing angle was lower (mean ICC = 0.58) than that of the swing speed for all but one bat sensor, indicating low accuracy. Moreover, in the high swing speed range, the accuracy of the swing speed tended to decrease for three bat sensors, but the trend of the swing angle was different among bat sensors. Significant systematic biases or proportional errors were found for all bat sensors, indicating the possibility of error correction. The sensor used in this study can help to evaluate the differences between players with different competition levels and hitting motions. Coaches need to be cautious in taking measurements of players with high swing speeds and in assessing slight changes within an individual.

2.
PLoS One ; 16(11): e0260520, 2021.
Article in English | MEDLINE | ID: mdl-34847199

ABSTRACT

In the game of softball, the batter should possess the necessary skills to hit the ball toward various directions with high initial speed. However, because various factors influence each other, there are limitations to the range that can be controlled by the batter's skill. This study was aimed at extracting the impact characteristics associated with the launch speed/direction and batted ball spin and clarifying the important skills required to improve the batter's hitting performance. In our experiments, 20 female softball players, who are members of the Japan women's national softball team, hit balls launched from a pitching machine. The movements of the ball and bat before, during, or after the impact were recorded using a motion capture system. Stepwise multiple regression analysis was performed to extract factors relating the side spin rate. The undercut angle (elevation angle between the bat's trajectory and the common normal between the ball and bat: ΔR2 = 0.560) and the horizontal bat angle (azimuth of bat's long axis at ball impact: ΔR2 = 0.299) were strongly associated with the side spin rate (total R2 = 0.893, p < 0.001). The undercut angle in opposite-field hitting was significantly larger than that in pull-side hitting (p < 0.001). The side spin rate was associated with the undercut angle because the bat's distal (barrel) side inclined downward (-29.6 ± 8.7°) at impact. The ball exit velocity was higher when it was hit at a smaller undercut angle (R2 = 0.523, p < 0.001). Therefore, it is deemed desirable to focus on maximizing the ball exit velocity rather than ball spin because the ball-bat impact characteristics vary inevitably depending on the launch direction. Meanwhile, the use of the ball delivery machine and the slower pitched ball are the limiting factors in the generalization of the findings.


Subject(s)
Athletic Performance , Baseball , Models, Theoretical , Sports Equipment , Acceleration , Adult , Female , Humans , Japan
3.
Development ; 148(18)2021 09 15.
Article in English | MEDLINE | ID: mdl-34097729

ABSTRACT

Proper organ development often requires nuclei to move to a specific position within the cell. To determine how nuclear positioning affects left-right (LR) development in the Drosophila anterior midgut (AMG), we developed a surface-modeling method to measure and describe nuclear behavior at stages 13-14, captured in three-dimensional time-lapse movies. We describe the distinctive positioning and a novel collective nuclear behavior by which nuclei align LR symmetrically along the anterior-posterior axis in the visceral muscles that overlie the midgut and are responsible for the LR-asymmetric development of this organ. Wnt4 signaling is crucial for the collective behavior and proper positioning of the nuclei, as are myosin II and the LINC complex, without which the nuclei fail to align LR symmetrically. The LR-symmetric positioning of the nuclei is important for the subsequent LR-asymmetric development of the AMG. We propose that the bilaterally symmetrical positioning of these nuclei may be mechanically coupled with subsequent LR-asymmetric morphogenesis.


Subject(s)
Body Patterning/physiology , Cell Nucleus/physiology , Digestive System/physiopathology , Drosophila/physiology , Morphogenesis/physiology , Animals , Cell Nucleus/metabolism , Digestive System/metabolism , Drosophila/metabolism , Drosophila Proteins/metabolism , Gene Expression Regulation, Developmental/physiology , Muscles/metabolism , Muscles/physiology , Myosin Type II/metabolism , Signal Transduction/physiology
4.
Front Sports Act Living ; 2: 579377, 2020.
Article in English | MEDLINE | ID: mdl-33345146

ABSTRACT

This study aimed to determine whether covariations among joint movements are utilized to stabilize hand orientation and movement and to determine which of the upper or lower extremities make effective use of the covariation. Joint angles during pitching were measured in 12 skilled baseball pitchers, using a motion capture system. The joint angles in 10 successful trials were used for the reconstructed motions. The reconstructed motion in the first condition was the same as for the measured motion. In the second condition, the reconstructed motion was generated with joint angles that were pseudo-randomly selected to artificially break off covariation in the measured joint-angle combination. In the third and fourth conditions, the reconstructed motions were generated with the same joint-angle combinations as the measured angles in the throwing arm and the stride leg, respectively, but pseudo-randomly selected in the other joint angles. Ten reconstructed motions were generated for each condition. Standard deviations (SDs) of hand orientation and movement direction were calculated and compared among the conditions. All SDs for the first condition were the smallest among the conditions, indicating that the movements in the measured condition used the covariation in joint angles to make the hand movement stable. The results also illustrated that some SDs in the fourth condition were smaller than those in the third condition, suggesting that the lower extremity made effective use of the covariation. These results imply that it is necessary not only to reduce variability in each joint but also to regulate joint movements to stabilize hand orientation and movement.

5.
Nanoscale Adv ; 2(6): 2339-2346, 2020 Jun 17.
Article in English | MEDLINE | ID: mdl-36133379

ABSTRACT

Plasmonic nanoparticles, such as gold nanoparticles (AuNPs), have been actively applied in solar vapor generation for seawater desalination and water purification, owing to their photothermal heating performances. Such nanoparticles have been frequently anchored within porous supporting materials to ensure easy handling and water absorption. However, there has been limited progress in improving the transport efficiency of light to nanoparticles within porous supports to achieve more effective photothermal heating. Here, we show an enhanced light absorption of AuNPs by supporting on a cellulose paper with tailored porous structures for efficient photothermal heating. The paper consists of AuNP-anchored cellulose nanofibers and cellulose pulp as the top and bottom layers, respectively, which provides dual-layered porous nano-microstructures in the perpendicular direction. Then, the bottom layer with pulp-derived microstructures reflects the transmitted light back to AuNPs within the top layer, which improves their light absorptivity. Thus, under 1 sun illumination, the dual-layered paper demonstrates superior performance in photothermal heating (increases from 28 °C to 46 °C) and solar vapor generation (1.72 kg m-2 h-1) compared with the single-layered AuNP-anchored cellulose nanofiber paper even at the same AuNP content. Furthermore, the water evaporation rate per AuNP content of the dual-layered paper is more than 2 times higher than those of the state-of-the-art AuNP-anchored porous materials under the same light irradiation. This strategy enables the efficient use of precious plasmonic nanoparticles for further development of solar vapor generation.

6.
Rinsho Byori ; 59(3): 236-42, 2011 Mar.
Article in Japanese | MEDLINE | ID: mdl-21560404

ABSTRACT

The creatine kinase MB (CK-MB) activity assay, which is based on the immunoinhibition method, has long been used in the diagnosis of acute myocardial infarction (AMI) because of its good cost-performance ratio and simplicity. However, the immunoinhibition method can not differentiate between CK-MB and MtCK, and therefore, CK-MB activity determined using this method is higher than the actual value in the sample which MtCK appears; this may lead to the misdiagnosis of AMI. We, therefore, evaluated the analytical and clinical performance of a new CK-MB reagent kit "L-System CK-MB MtO," which can inhibit MtCK. The kit yielded good precision and linearity and no interference from hemolysis, bilirubin or chyle. A good correlation was observed between the values determined using this kit and those determined using the conventional kit for samples of patients with acute coronary syndromes. However, differences were observed in the CK-MB values determined for samples from patients with malignancy. CK isoenzyme analysis indicated that MtCK was present in all these samples. The new method permits the accurate estimation of CK-MB activity in samples of patients with high serum levels of MtCK activity and indicates that the conventional method has a high false-positive rate for CK-MB activity. CK-MB activity in the serum of healthy individuals measured using the new and the conventional kits was 1.9-9.5 U/l and 4.5-15.3 U/l, respectively. The new kit, enables accurate estimation of CK-MB activity and is, therefore, more useful than the conventional kit in the diagnosis of acute coronary syndromes.


Subject(s)
Acute Coronary Syndrome/diagnosis , Creatine Kinase, MB Form/blood , Immunoenzyme Techniques/methods , Reagent Kits, Diagnostic , Biomarkers/blood , Creatine Kinase, Mitochondrial Form/blood , Humans , Reproducibility of Results
7.
Jpn J Infect Dis ; 62(5): 386-9, 2009 Sep.
Article in English | MEDLINE | ID: mdl-19762991

ABSTRACT

A novel genotyping method for methicillin-resistant Staphylococcus aureus (MRSA), the phage open-reading frames typing (POT) method, was evaluated using 92 MRSA isolates collected from blood cultures between 1991 and 2003 at Nagoya University Hospital. These strains were divided into 64 distinct POT types, classified into 21 genotypes by pulsed-field gel electrophoresis (PFGE) using SmaI, and analyzed with the DICE coefficient of 80% in dendrogram analysis, with 48 subtypes analyzed with the DICE coefficient of 100%. The discriminatory indices of these three methods were 0.988, 0.719, and 0.953, respectively. The first and second prevalent PFGE subtypes A1 and A2, which comprised 16 and 13 isolates recovered serially during the study period, were both divided into 11 distinct POT types. Six isolates belonging to PFGE subtype A1 were indistinguishable with POT. The six isolates were probably involved in an outbreak. Phenotypic analysis suggested that these isolates were the siblings of the New York/Japan clone which are prevalent in many Japanese hospitals. In conclusion, in the strain population studied, POT is a more rapid and discriminatory method than PFGE, and is a useful epidemiological tool for evaluating the available clinical information.


Subject(s)
Bacterial Typing Techniques/methods , Disease Outbreaks , Methicillin-Resistant Staphylococcus aureus/classification , Open Reading Frames , Prophages/genetics , Staphylococcal Infections/epidemiology , Staphylococcus Phages/genetics , Bacteremia/epidemiology , Bacteremia/microbiology , Cluster Analysis , DNA Fingerprinting/methods , Electrophoresis, Gel, Pulsed-Field/methods , Genotype , Humans , Japan , Methicillin-Resistant Staphylococcus aureus/isolation & purification , Methicillin-Resistant Staphylococcus aureus/virology , Molecular Epidemiology/methods , Sensitivity and Specificity , Staphylococcal Infections/microbiology
8.
Rinsho Byori ; 56(1): 29-35, 2008 Jan.
Article in Japanese | MEDLINE | ID: mdl-18320661

ABSTRACT

Although liver transplantation (LT) is frequently associated with thrombocytopenia, thrombopoiesis following LT remains to be evaluated. We analyzed platelet counts (PLT), immature Platelet Fraction (IPF), and thrombopoietin (TPO) in 8 patients with LT. PLT and IPF were measured using Sysmex XE-2100. TPO was measured with Human TPO ELISA Kit. In 7 of 8 patients with LT, IPF increased prior to the elevation of platelet counts. In 5 of 7 patients with increased IPF, TPO levels increased simultaneously with IPF, suggesting that IPF may reflect the production of platelets in patients with LT. IPF and TPO might be useful to monitor the platelet production in patients following LT.


Subject(s)
Liver Transplantation/physiology , Platelet Count , Enzyme-Linked Immunosorbent Assay , Humans , Liver Diseases/blood , Liver Diseases/surgery , Postoperative Period , Thrombopoietin/biosynthesis , Thrombopoietin/blood
9.
J Clin Lab Anal ; 21(3): 140-6, 2007.
Article in English | MEDLINE | ID: mdl-17506480

ABSTRACT

The presence of high-molecular intestinal ALP (HIALP) overlapping with bone ALP in the alpha(2)beta region has been demonstrated. In this study we evaluated a method of separating HIALP after its conversion into ALP(5) by the action of protease. Serum samples from patients were mixed with protease at a ratio of 5:1 and left at room temperature for more than 30 min. The protease-treated and nontreated samples were both subjected to agarose gel electrophoresis. Patients who showed a decrease in ALP(3) in the alpha2beta region and an increase in ALP(5) in the beta region were regarded as HIALP-positive. HIALP was observed in 26.7-33.1% of patients with liver diseases, collagen diseases, and diabetes mellitus. Renal disease was ABO blood group-dependent and showed high positive rates for blood groups B and O. The HIALP-positive rate was low (7.1-15.5%) in patients with cardiovascular diseases, malignant tumors, and other disorders. ALP(5) was also observed in 98.4% of HIALP-positive patients with liver diseases. In patients with collagen diseases or diabetes mellitus, the positive rate of ALP(5) was 40.4-66.7%. In conclusion, this method, in which HIALP is converted into ALP(5) by protease pretreatment and is separated from bone ALP, allows HIALP to be identified while other fractions remain unaffected.


Subject(s)
Alkaline Phosphatase/blood , Electrophoresis, Agar Gel/methods , Intestines/enzymology , ABO Blood-Group System , Alkaline Phosphatase/chemistry , Biomarkers/blood , Bone and Bones/enzymology , Hospitals, University , Humans , Isoenzymes/blood , Isoenzymes/chemistry , Molecular Weight , Neuraminidase/chemistry , Peptide Hydrolases/chemistry
10.
J Clin Lab Anal ; 21(3): 133-9, 2007.
Article in English | MEDLINE | ID: mdl-17506485

ABSTRACT

The presence of high-molecular intestinal alkaline phosphatase (HIALP) different from bone ALP detected in the alpha(2)beta region was recently clarified. In this study we used a novel method in which HIALP was detected after conversion to ALP(5) by protease to investigate the clinical significance of the appearance of HIALP in patients with chronic liver disease. The subjects were 241 patients with chronic liver disease. When a decrease in ALP(3) in the alpha(2)beta region and an increase in ALP(5) in the beta region were noted, the patient was judged HIALP-positive. In the patients with chronic liver disease, the total ALP activity (T-ALP) increased with progression of the pathology in the order of chronic hepatitis (CH), liver cirrhosis (LC), and hepatocellular carcinoma (HCC). HIALP appeared in 22.4% and 49.3% of patients with CH and LC, respectively, but the positivity rate decreased to 30.4% in HCC. As autoimmune liver diseases, primary biliary cirrhosis (PBC) and autoimmune hepatitis (AIH) were investigated. T-ALP was lower in PBC+AIH than in LC and HCC, but the HIALP-positive rate was high (44.4%). The HIALP-positive rate was dependent on ABO blood groups, and was high in blood groups B and O. In conclusion, the HIALP-positive rate was particularly high in patients with chronic liver disease, and was related to the pathological progression, which suggests that the method is clinically useful.


Subject(s)
Alkaline Phosphatase/blood , Intestines/enzymology , Liver Diseases/enzymology , ABO Blood-Group System , Aged , Biomarkers/blood , Chronic Disease , Electrophoresis, Agar Gel , Hospitals, University , Humans , Isoenzymes/blood , Liver Diseases/blood , Liver Diseases/pathology , Male , Middle Aged , Molecular Weight
11.
Thromb Res ; 118(4): 463-9, 2006.
Article in English | MEDLINE | ID: mdl-16253312

ABSTRACT

Immature platelet fraction (IPF) has been measured by fully automated analyzer (XE-2100) as reticulated platelet (RP) which is reflected with thrombopoiesis in bone marrow. IPF value in the healthy volunteers was 3.3% (1.0-10.3) and upper 95% confidential interval (95% CI) of IPF was determined as 7.7%. IPF was significantly high in the patients with idiopathic thrombocytopenic purpura (ITP; 17.4%, 1.2-53.2%) and recovery phase of post-chemotherapy, and significantly low in nadir phase of post-chemotherapy, and within normal range in the patients with ITP in complete remission (CR) and with aplastic anemia (AA). Total count of IPF was significantly low in patients with ITP, AA or post-chemotherapy. Mean platelet volume (MPV) was significantly high in only patients with ITP. IPF 7.7% is best point for highest sensitivity (86.8%) and specificity (92.6%) in diagnosis of ITP and recovery phase of post-chemotherapy. In receiver operating characteristic curve for diagnosis of ITP and recovery phase of post-chemotherapy, IPF was significantly more useful than MPV. These results show that IPF reflects the pathology of thrombocytopenic disorders, and that measurement of IPF is useful for the differential diagnosis and analysis of platelet kinetics.


Subject(s)
Anemia, Aplastic/diagnosis , Blood Platelets , Platelet Count/methods , Purpura, Thrombocytopenic, Idiopathic/diagnosis , Thrombopoiesis , Adult , Anemia, Aplastic/blood , Anemia, Aplastic/drug therapy , Blood Platelets/classification , Female , Humans , Male , Middle Aged , Platelet Count/instrumentation , Predictive Value of Tests , Purpura, Thrombocytopenic, Idiopathic/blood , Purpura, Thrombocytopenic, Idiopathic/drug therapy , Remission Induction , Sensitivity and Specificity
12.
Rinsho Byori ; 53(8): 685-91, 2005 Aug.
Article in Japanese | MEDLINE | ID: mdl-16190352

ABSTRACT

Although opportunistic infection including fungal infection is often associated with living donor liver transplantation followed by immunosuppressive therapy, antifungal agents are empirically given to most patients without a definitive diagnosis of fungal infection. Indeed, there is no diagnostic test available, that shows both high sensitivity and specificity for fungal infection. In this study, we developed a polymerase chain reaction(PCR)-based system for rapid diagnosis of fungal infection. This system consisted of two PCR steps: the first PCR for most species of fungi and 4 kinds of nested PCR for Aspergillus or Penicillium (ASP/PEN), Candida glabrata (C. glab), other Candida species including Candida albicans, Candida parapsilosis, Candida tropicalis, and Candida guiliermondii (CAN), and a broad spectrum of fungi (Broad). The newly developed PCR-based system was applied to 28 recipients of with living donor liver transplantation to determine its clinical usefulness in early and differential diagnosis of fungal infection. A total of 514 blood samples from 28 patients ware analyzed. Nested PCR assays were positive in 118 samples from 19 patients: 4 patients (30 samples) with ASP/PEN, 5 patients (29 samples) with C. glab, 12 patients (61 samples) with CAN. All of these samples were positive with nested PCR for Broad as well. Even in samples that were negative on blood culture or ELISA for Aspergillus antigen, nested PCR assays were able to amplify the fungal DNA. Furthermore, all samples positive for Aspergillus antigen tested positive on nested PCR. In conclusion, the PCR-based system we developed was thought to be useful for early diagnosis of fungal infection.


Subject(s)
Liver Transplantation , Living Donors , Mycoses/microbiology , Polymerase Chain Reaction/methods , Diagnosis, Differential , Humans , Opportunistic Infections/microbiology , Sensitivity and Specificity
13.
Kansenshogaku Zasshi ; 78(10): 891-7, 2004 Oct.
Article in Japanese | MEDLINE | ID: mdl-15560379

ABSTRACT

Equivalent MIC breakpoints to detect beta-lactamase negative ampicillin resistant Haemophilus influenzae (BLNAR) were controversial. We studied the relationship of drug resistance with gene alterations in 74 clinical isolates of H. influenzae. Out of 74 isolates, 26 showed MIC of ampicillin (ABPC) > or = 1 microg/ml. All isolates, except one, with MIC of ABPC > or = 4 microg/ml were found to produce beta-lactamase, while all 19 isolates with MIC of ABPC at 1 or 2 microg/ml were non-producing. Twenty-six ABPC resistant isolates were subjected to the analysis of genes involved in the drug resistance such as pbp3-1 pbp3-2, and TEM by the Haemophilus influenzae gene detection kit (Wakunaga Pharmaceutical Co., Ltd.) according to the supplier's instructions. Three (21.4%) of 14 beta-lactamase non-producing isolates with ABPC-MIC of 1 microg/ml had mutations of pbp3-1 gene, while all 5 non-producing isolates with ABPC-MIC of 2 microg/ml showed mutations of both pbp3-1 and pbp3-2 genes. Accordingly, it seems appropriate to set ABPC-MIC > or = 2 microg/ml for detection of BLNAR. In this study, six (8.1%) of 74 isolates were found to be BLNAR, and all of these six isolates were derived from patients of 5 year-old or younger.


Subject(s)
Ampicillin Resistance/genetics , Haemophilus Infections/microbiology , Haemophilus influenzae/drug effects , Haemophilus influenzae/isolation & purification , beta-Lactamases/metabolism , Anti-Bacterial Agents/pharmacology , Child, Preschool , Drug Resistance, Bacterial , Haemophilus Infections/epidemiology , Haemophilus influenzae/genetics , Humans , Imipenem/pharmacology , Meropenem , Microbial Sensitivity Tests , Molecular Epidemiology , Prevalence , Reagent Kits, Diagnostic , Thienamycins/pharmacology
14.
Thromb Haemost ; 90(1): 59-63, 2003 Jul.
Article in English | MEDLINE | ID: mdl-12876626

ABSTRACT

We report the identification in a Japanese family of a novel homozygous W486C mutation in the protease domain of coagulation factor XII (FXII), which was associated with the reduction of plasma FXII activity and antigen level to less than 5% of normal. Sequences of each exon for FXII gene was analysed in family members by polymerase chain reaction (PCR) amplification followed by a direct sequencing method. Sequence analysis showed a homozygous substitution of G to C at nucleotide position 10587 (cDNA position 1458) in proband's FXII gene, resulting in a Trp to Cys substitution in the catalytic domain of FXII. PCR-fragment length polymorphism analysis of 55 healthy volunteers showed no such mutation. Transient expression of FXII in HK-293T cells and analysis of FXII antigen in culture media and cell lysates showed reduced secretion of mutant protein by more than 84% relative to that of wild type protein although the intracellular contents were similar. Our results suggest that the reduced secretion of FXII protein was due to incorrect folding caused by the introduction of Cys486. We designated this mutation as FXII Mie-1.


Subject(s)
Amino Acid Substitution , Factor XII Deficiency/genetics , Factor XII/genetics , Mutation, Missense , Catalytic Domain/genetics , Cell Line , Exons/genetics , Factor XII/chemistry , Factor XII/metabolism , Female , Humans , Japan , Kidney , Male , Middle Aged , Protein Biosynthesis , Protein Folding , Recombinant Fusion Proteins/chemistry , Recombinant Fusion Proteins/metabolism
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