Kagawa University

About: Kagawa University is a education organization based out in Takamatsu, Japan. It is known for research contribution in the topics: Cancer & Population. The organization has 6028 authors who have published 11918 publications receiving 224111 citations. The organization is also known as: Kagawa Daigaku.

Insight into the mechanism of reproductive dysfunction caused by neonicotinoid pesticides.

Abstract: Neonicotinoids, which were developed in the 1990 s as an insecticide having selective toxicity, were later found to cause reproductive abnormalities in experimental animals. In Japan there is an attempt to preserve endangered animals, including the Japanese crested ibis, and there is a question of whether neonicotinoids affect the reproduction of this bird, since they are used in its habitat. Hence, we investigated whether the daily oral administration of the neonicotinoid clothianidin (CTD) has any deleterious effects on the reproductive function of mature male only or both young male and female quails as experimental animals. Vacuolization and the number of germ cells having fragmented DNA in seminiferous tubules, as well as the number and size of vacuoles in hepatocytes, increased dose-dependently. The ovaries showed abnormal histology in the granulosa cells, which produce progesterone. There were significant differences in egg-laying rates and embryo weights between the groups. Glutathione Peroxidase 4 (GPx4) and Manganese Superoxide Dismutase (Mn-SOD), which protect the organism from oxidative damage, showed a dose-dependent decrease. Thus, it is possible neonicotinoids affect the bird's reproductive system through oxidative stress, reflecting an imbalance between the production of reactive oxygen species (ROS) and a biological system's ability to readily detoxify the reactive intermediates or easily repair the resulting damage. Responding to our study, Sado Island has since succeeded in breeding Japanese crested ibis in the wild without the use of neonicotinoids.

Effect of electron irradiation on the phase stability of Fe–9Zr–3B alloy

Abstract: Effect of electron irradiation on the structural and phase stability of amorphous phase and crystallites in Fe–9Zr–3B alloy was examined. Amorphous ribbons were produced by a single-roller-melt-spinning method. Some specimens were annealed at 873 and 1073 K to obtain α-Fe and the duplex structure composed of α-Fe phase and Fe–Zr intermetallic compounds, respectively. Electron irradiation on the amorphous and crystalline specimens were performed at dose rates of 1.7×1024 and 7.5×1023 m−2 s−1. The electron irradiation accelerated crystallization from the amorphous phase, while the α-Fe and the intermetallic compounds remained stable in annealed specimens. During electron irradiation, cubic-Fe2Zr crystallized from the amorphous phase prior to α-Fe precipitates in melt-spun specimens without annealing, while the α-Fe precipitation advanced during annealing

Monoclonal antibody to tumor necrosis factor-related apoptosis-inducing ligand receptor 2 (TRAIL-R2) induces apoptosis in primary renal cell carcinoma cells in vitro and inhibits tumor growth in vivo.

Abstract: Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) triggers apoptosis in a variety of tumor cells through two of its receptors: TRAIL-R1 and TRAIL-R2. We investigate the susceptibility of human renal cell carcinoma (RCC) cells to TRM-1 and HGS-ETR2, 2 human monoclonal agonistic antibodies specific for TRAIL-R1 and TRAIL-R2, respectively. HGS-ETR2 effectively induced apoptotic cell death in 10 of 11 cell cultures, including 2 human RCC cell lines and 9 human primary RCC cell cultures, with a more pronounced effect after preincubation with anti-human IgG Fc. In contrast, TRM-1 was effective in only 1 primary RCC cell culture. The increased effectiveness of HGS-ETR2 for inducing cell death might have been affected by differences in the cell-surface expression of the 2 TRAIL receptors, namely that TRAIL-R2 but not TRAIL-R1 was frequently expressed in most of the RCC cells tested. The activities of caspase-9, -8, -6, and -3 were increased with HGS-ETR2-induced apoptosis, and cell death could be blocked by specific caspase inhibitors for caspase-9, -8, and -3, and the general caspase inhibitor. In vivo administration of HGS-ETR2 with or without cross-linker significantly suppressed tumor growth of subcutaneously inoculated human RCC xenografts in immunodeficient mice. These results suggest the potential utility of TRAIL-R2 antibody as a novel therapeutic agent in RCC.

Visit-to-visit variability in blood pressure over a 1-year period is a marker of left ventricular diastolic dysfunction in treated hypertensive patients.

Abstract: Although visit-to-visit variability in systolic blood pressure (SBP) has recently been demonstrated to be a strong predictor of stroke, there are no data about relationships between SBP variability and cardiac damage in hypertensive patients. We compared relationships between visit-to-visit variability in SBP and left ventricular (LV) diastolic dysfunction with the relationships between the mean SBP value and cardiac parameters in treated patients. Forty treated hypertensive patients (69 ± 9 years of age) had their blood pressure measured at outpatient clinics every 1 or 2 months over a 1-year period. The standard deviation (s.d.) of SBP and the difference between the maximum and minimum SBPs during this year were calculated to assess visit-to-visit variability. The mean SBP during the year was also calculated. LV diastolic function was assessed by the ratio (E/A) of early (E) and late (A) diastolic transmitral flows, early diastolic mitral annular velocity (e') and the ratio (E/e') of E to e' using Doppler echocardiography. E/A only correlated with the s.d. of SBP (r=-0.327, P=0.040), whereas e' correlated with s.d. of SBP (r=-0.496, P=0.001) and maximum-minimum SBP difference (r=-0.490, P=0.001). E/e' correlated with s.d. of SBP (r=0.384, P=0.014), maximum-minimum SBP difference (r=0.410, P=0.009), and the mean value of SBP (r=0.349, P=0.028). Multiple regression analysis demonstrated only the maximum-minimum SBP difference independently associated with E/e' (β=0.410, P=0.009). Thus, the visit-to-visit variability of SBP showed better correlation with LV diastolic dysfunction than mean values of SBP. High visit-to-visit variability of SBP was associated with LV diastolic dysfunction and may constitute a high risk for diastolic heart failure in hypertensive patients.