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1.
J Sports Med Phys Fitness ; 64(6): 532-538, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38319648

ABSTRACT

BACKGROUND: In javelin, although many previous studies have examined throwing movements that can increase initial velocity, the characteristics of throwing arm movement an elongated implement have not been clarified. The purpose of the present study was to examine the characteristics of the throwing movement of an elongated implement by comparing throwing movement between a javelin and baseball. METHODS: Twelve male javelin throwers were asked to perform a javelin throw (JT) and a baseball long toss (LT) twice. The three-dimensional coordinates of reflective markers attached to the athlete's body, javelin, and baseball were measured using an optical motion capture system. %Trajectory was used as an index to evaluate the degree to which the hand was moved linearly during the throw. A smaller value of this indicator meant that the hand was move closer to a straight line. The joint angles in the throwing arm were obtained by calculating the Euler angles between body segments. These data were used to compare JT and LT. RESULTS: %Trajectory showed that JT was significantly smaller than LT. Significant differences in the joint angles of the throwing arm were noted between JT and LT. CONCLUSIONS: JT showed a kinematic pattern in which the hand was moved more linearly than in baseball long toss.


Subject(s)
Arm , Baseball , Movement , Humans , Male , Baseball/physiology , Biomechanical Phenomena , Movement/physiology , Arm/physiology , Young Adult , Adult
2.
J Hum Kinet ; 89: 43-52, 2023 Oct.
Article in English | MEDLINE | ID: mdl-38053957

ABSTRACT

In javelin training, many athletes improve their throwing technique by throwing from a slower run-up velocity than in competitions. However, whether the acquisition of javelin velocity in throwing from a slower run-up velocity is the same as in full run-up throwing is unclear. The purpose of this study was to clarify the differences in the contribution of each movement to the javelin velocity caused by changes in the run-up velocity within an individual. Twelve collegiate male javelin throwers were included in this study. Athletes performed two types of throws: one-cross throwing (Cross) and full run-up throwing (Run). The coordinates of reflective markers attached to the thrower's body and the javelin were recorded using an optical motion capture system. The percentage contribution of each joint movement to the javelin velocity was calculated and compared between Cross and Run. Cross had a lower contribution of trunk forward lean to forward and upward javelin velocities compared to Run. On the other hand, Cross had a higher contribution of trunk counter-clockwise rotation to forward and upward javelin velocities than Run. These results suggest that as the velocity of run-up changes within an individual, the acquisition of javelin velocity also changes.

3.
Front Sports Act Living ; 5: 1092520, 2023.
Article in English | MEDLINE | ID: mdl-37090818

ABSTRACT

It is widely acknowledged that understanding the physical mechanics of the flight trajectories of four-seam fastballs and breaking balls is crucial for players and coaches to enhance pitching performance. The characteristics of the flight trajectories of four-seam fastballs and breaking balls have been revealed; however, the relationship between them has not been examined. Here, we show the characteristics of the flight trajectory of breaking balls from the four-seam fastballs. We found that the direction of the deviation of the curveballs could be generally predicted from that of the four-seam fastballs. We also found that the limits of the deviation of the sliders can be determined from the direction of the deviation of the four-seam fastball. This study revealed the deviation of the breaking ball from the four-seam fastballs, which clearly showed the differences in the characteristics between curveballs and sliders. This study moved forward with the description of the physical properties of each pitch type and allowed us to obtain valuable insights and practical implications.

4.
Biosci Biotechnol Biochem ; 87(2): 208-216, 2023 Jan 24.
Article in English | MEDLINE | ID: mdl-36367537

ABSTRACT

Phytophthora are plant pathogens that damage agricultural products. Lycosides (1a-d), found in vegetable juice, have the potential to curb the rapid outbreak and crop damage caused by the asexual reproduction of Phytophthora. Here, aglycones 2a, b with slightly higher activity than lycosides were synthesized as a diastereomeric mixture (mix-2) possessing activity (IC50 = 4.1 µm) comparable with that of lycosides. The importance of the cyclohexanone structure and side-chain length was demonstrated via structure-activity relationship analysis using synthetic intermediates. In addition, the action mechanism of lycosides was investigated using transcriptome analysis, which revealed a contribution to proline biosynthesis inhibition, a process crucial for the asexual reproduction of Phytophthora. These findings indicate that lycosides (and aglycone) are environmentally benign agents that can be used for protecting agricultural products from Phytophthora pathogens.


Subject(s)
Phytophthora , Plants , Reproduction, Asexual , Structure-Activity Relationship
5.
J Agric Food Chem ; 70(40): 12878-12884, 2022 Oct 12.
Article in English | MEDLINE | ID: mdl-36190399

ABSTRACT

Phytophthora is a genus of fungus-like microorganisms that damages important crops, such as potatoes and tomatoes. Its asexual reproduction, which results in the production of numerous motile zoospores, is the cause of quick and severe outbreaks and crop damage. The search for substances that selectively inhibit the asexual reproduction of Phytophthora led to the isolation of the known natural products naringenin and flazin from tomato juice. They inhibit the sporangia formation of Phytophthora capsici at IC50 values of 8.8 and 7.2 µM. The study of the structure-activity relationship of 11 flavonoids, including naringenin, demonstrated that genistein was the most active (IC50 = 4.6 µM) and flavonols/flavanonols possessing the 3-hydroxy function showed little activity (IC50 = from 100 to >1000 µM). To demonstrate the mechanism of asexual reproduction inhibition by genistein, transcriptome analysis was carried out, which revealed the downregulation of some genes related to cell differentiation. The results suggest that certain flavonoids are environmentally benign agents that could be used to protect agricultural products from Phytophthora pathogens.


Subject(s)
Biological Products , Phytophthora , Solanum lycopersicum , Flavonols , Gene Expression Profiling , Genistein , Solanum lycopersicum/genetics , Phytophthora/physiology , Plant Diseases , Reproduction, Asexual , Structure-Activity Relationship
6.
Int J Hematol ; 112(1): 105-114, 2020 Jul.
Article in English | MEDLINE | ID: mdl-32253664

ABSTRACT

This case-control study investigated immune thrombocytopenic purpura (ITP) risk following live, inactivated, and simultaneous vaccination, with a focus on infants aged < 2 years. We matched case patients with ITP to one or two control patients with other diseases by institution, hospital visit timing, sex, and age. We calculated McNemar's pairwise odds ratios (ORs [95% confidence interval]) with 114 case-control pairs. The case group had 27 (44%) males and 22 (35%) infants, and the control group included 49 (43%) males and 42 (37%) infants. For all age groups, the McNemar's OR for ITP occurrence was 1.80 (0.54-6.84, p = 0.64) for all vaccines. Among infants, these were 1.50 (0.17-18.0, p = 0.50) for all vaccines, 2.00 (0.29-22.1, p = 0.67) for live vaccines, and 1.00 (0.01-78.5, p = 0.50) for inactivated vaccines. Sex-adjusted common ORs for simultaneous vaccination were 1.52 (0.45-5.21, p = 0.71) for all vaccines, 1.83 (0.44-7.59, p = 0.40) for inactivated vaccines only, and 1.36 (0.29-6.30, p = 0.69) for mixed live and inactivated vaccines. In infants, these were 1.95 (0.44-8.72, p = 0.38), 1.41 (0.29-6.94, p = 0.67) and 2.85 (0.43-18.9, p = 0.28), respectively. These limited data suggest no significant ITP risk following vaccinations or simultaneous vaccination in any age group, including infants.


Subject(s)
Purpura, Thrombocytopenic, Idiopathic/etiology , Vaccination/adverse effects , Vaccines, Attenuated/adverse effects , Vaccines, Inactivated/adverse effects , Vaccines, Live, Unattenuated/adverse effects , Adolescent , Adult , Case-Control Studies , Child , Child, Preschool , Female , Humans , Male , Risk , Vaccination/methods , Vaccines, Attenuated/administration & dosage , Vaccines, Inactivated/administration & dosage , Vaccines, Live, Unattenuated/administration & dosage , Young Adult
7.
J Agric Food Chem ; 64(49): 9352-9355, 2016 Dec 14.
Article in English | MEDLINE | ID: mdl-27960276

ABSTRACT

Violaxanthin and 9-cis-violaxanthin (major epoxycarotenoids in fruit) were prepared from mango fruit, purified, and converted to other carotenoids under acidic conditions. The resulting carotenoid structures were then analyzed in detail. Not only violaxanthin but also 9-cis-violaxanthin were found to be converted to (8S,8'S)-, (8S,8'R)-, and (8R,8'R)-auroxanthin at an approximate ratio of 4:6:1. Antioxidant activities of violaxanthin, 9-cis-violaxanthin, (8S,8'S)-auroxanthin, and (8S,8'R)-auroxanthin were examined. They possessed potent lipid peroxidation inhibitory and very weak 1O2 quenching activities.


Subject(s)
Antioxidants/chemistry , Mangifera/chemistry , Plant Extracts/chemistry , Acids/chemistry , Carotenoids/chemistry , Fruit/chemistry , Hydrolysis , Isomerism , Molecular Structure , Xanthophylls/chemistry
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