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1.
We characterized the L-carnitine transport system which is defective in the kidney of juvenile visceral steatosis (JVS) mice by using kidney slices and carnitine-related compounds, and evaluated the influence of the transport defect on the biosynthetic pathway of carnitine. The JVS mouse transport system defect, calculated as the difference in the transport activity between control and JVS mice, was simulated in control by gamma-butyrobetaine (gamma-BB) and acetyl L-carnitine. gamma-BB hydroxylase activity in the liver of JVS mice was double that of control mice, but the hepatic level of gamma-BB in JVS mice was lower than in control mice, suggesting that the conversion of gamma-BB to carnitine is not activated in the liver of JVS mice. JVS mice showed higher fractional excretions not only of L-carnitine but also of gamma-BB and acetyl L-carnitine than control mice, indicating disturbed reabsorption of gamma-BB and acetyl L-carnitine. The disturbed reabsorption of gamma-BB in JVS mice is consistent with the fact that the amount of urinary gamma-BB in JVS mice was four times that of control. The sum of the concentrations of L-carnitine, acetyl L-carnitine and gamma-BB in the urine of JVS mice was not significantly different from that of the control, suggesting no remarkable increase of biosynthesis of gamma-BB and carnitine in JVS mice. All these findings suggest that the carnitine transport system plays a role in the transport of gamma-BB and that carnitine deficiency is aggravated by the disturbed reabsorption of gamma-BB in the kidney. 相似文献
2.
The diet in Japan has improved, but calcium intake has not increased for the past ten years, and it remains insufficient. To prevent osteoporosis, instruction in nutrition is directed at increasing calcium intake. We studied the effect of measuring bone mineral density on calcium intake in people receiving nutrition education. Intake of other nutrients was also measured. The subjects were 87 healthy women living in an agricultural region (Yamanashi Prefecture). They were members of a group formed to improve the diet of people in their area. For three days in October 1992 and in August 1994 food-weight records were obtained. A total of 76 of the 87 women chose to have their bone mineral density measured. The measurements before the first nutrition assessment in 1992. The intake of almost all nutrients tended to be greater in 1994 than in 1992. Calcium intake exceeded the minimum daily requirement (600mg). Calcium intake increased between 1992 and 1994 only in the subjects whose bone mineral density had been measured. Calcium intake decreased in the other subjects. Therefore, nutrition education programs aimed at preventing osteoporosis may be more effective if bone mineral density is measured. In addition, an appropriate balance of other nutrients can be maintained as the intake of calcium is increased. 相似文献
3.
A novel phytoecdysteroid, vitexirone, has been isolated from a MeOH extract of the root bark of the East African medicinal plantVitex fisherii by recycling high-performance liquid chromatography on a semipreparative scale. In addition, three known phytoecdysteroids, 20-hydroxyecdysone, ajugasterone C, and turkesterone, also were isolated. The structure of vitexirone has been established spectroscopically. The position and stereochemistry of the 11--hydroxy group of ajugasterone C and vitexirone were confirmed by the1H-1H homonuclear COSY NMR data. These phytoecdysteroids disrupt the molting process of the pink bollwormPectinophora gossypiella. 相似文献
4.
Yoshihiro Hirata Kazuyoshi Sakeda Yumi Matsushita Kinji Shimada Yoshimi Ishihara 《Journal of the American Ceramic Society》1989,72(6):995-1002
Submicrometer SiO2 -Al2 O3 powders with compositions of 46.5 to 76.6 wt% Al2 O3 were prepared by hydrolysis of mixed alkoxides. Phase change, mullite composition, and particle size of powders with heating were analyzed by DTA, XRD, IR, BET, and TEM. As-produced amorphous powders partially transformed to mullite and Al-Si spinel at around 980°C. The compositions of mullite produced at 1400° and 1550°C were richer in Al2 O3 than the compositions of stable mullite solid solutions predicted from the phase diagram of the SiO2 -Al2 O3 system. Particle size decreased with increasing Al2 O3 content. The sintered densities depended upon the amount of SiO2 -rich glassy phase formed during sintering and the green density expressed as a function of particle size. 相似文献
5.
Motoyuki Karita Koji Asaka Hitoshi Nakahara Yahachi Saito 《Journal of Materials Science》2013,48(2):936-940
Electrical conductance of multi-walled carbon nanotubes (MWCNTs) with closed and open tips contacting with a gold (Au) electrode was studied by in situ transmission electron microscopy. When a current density through the contact region reached a threshold value of 2.6 × 108 A/cm2, the MWCNT tip was embedded into the Au surface by local melting of Au, and the total resistance was reduced with the increase of the contact area. Conductance per unit area at the contact between the MWCNT and Au electrode for the open-ended MWCNT is four times larger than that for the close-ended one, which is due to the direct connection of inner walls of the open-ended MWCNT with the Au surface. 相似文献
6.
Tomoya Hasegawa Mikako Ito Satoru Hasegawa Masaki Teranishi Koki Takeda Shuto Negishi Hiroshi Nishiwaki Jun-ichi Takeda Tyler W. LeBaron Kinji Ohno 《International journal of molecular sciences》2022,23(5)
Molecular hydrogen ameliorates pathological states in a variety of human diseases, animal models, and cell models, but the effects of hydrogen on cancer have been rarely reported. In addition, the molecular mechanisms underlying the effects of hydrogen remain mostly unelucidated. We found that hydrogen enhances proliferation of four out of seven human cancer cell lines (the responders). The proliferation-promoting effects were not correlated with basal levels of cellular reactive oxygen species. Expression profiling of the seven cells showed that the responders have higher gene expression of mitochondrial electron transport chain (ETC) molecules than the non-responders. In addition, the responders have higher mitochondrial mass, higher mitochondrial superoxide, higher mitochondrial membrane potential, and higher mitochondrial spare respiratory capacity than the non-responders. In the responders, hydrogen provoked mitochondrial unfolded protein response (mtUPR). Suppression of cell proliferation by rotenone, an inhibitor of mitochondrial ETC complex I, was rescued by hydrogen in the responders. Hydrogen triggers mtUPR and induces cell proliferation in cancer cells that have high basal and spare mitochondrial ETC activities. 相似文献
7.
Saitoh M Asaka K Arai M Kawabata A Kanoh S Kanoh T 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2002,43(4):243-249
In order to evaluate the relationship between nasal carriers of S. aureus and their history of allergic diseases, the total serum IgE titer, the hemogramme pattern, and the titers of specific IgE antibody to Staphylococcal enterotoxins A and B (SEA and SEB) and of specific IgG antibody to SEB were investigated in 98 trade school students. Fifteen (15.3%) of the 98 students were sensitized to SEA and/or SEB (40.0% to SEA and 93.3% to SEB). In this group, 11 subjects were S. aureus carriers (73.0%) and 12 had a history of allergic diseases (80.0%). Low levels of specific IgG antibody to SEB were identified from both S. aureus carriers and non-carriers. The S. aureus carriers had significantly higher levels of total IgE titer than the non-carriers and the individuals with a history of allergic diseases had significantly higher total IgE titer levels than those having no history of allergic diseases (p < 0.01). In the hemogramme patterns of S. aureus carriers, a significant positive correlation was observed between the total IgE antibodies and the eosinophil rate (p < 0.05), and a negative correlation (p < 0.001) was recognized between the neutrophil and the lymphocyte rates. 相似文献
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10.
Compact structure and flexibility is normally considered as a pair of incompatible characteristics for legged microrobots. Most robots choose complex structure of multi-joint legs to attain the flexibility, while some microrobots have poor flexibility for miniaturization. To attain a microrobot with both compact structure and flexible locomotion, we designed a novel type of biomimetic locomotion employing ionic conducting polymer film (ICPF) actuators as one-DOF legs. We developed several prototype microrobots using this locomotion. In this paper, a microrobot using this biomimetic locomotion, named Walker-3, utilizing six ICPF actuators with two-DOF motion is developed. It is 30 mm in length, 55 mm in width and 8 mm in height (in static state). Experimental results indicate that Walker-3 can attain 6 mm/s of walking speed and 7.1 deg/s of rotating speed and climb on a 30° ascent at a speed of 0.5 mm/s with control signal of 10 V, 0.5 Hz. It is also suitable for uncertain terrain, such as climbing on a stairs less than 2 mm high and striding over a pit less than 5 mm wide. It has better flexibility, balance and load ability than its predecessors. We compared it with some legged microrobots and the result shows a microrobot with this biomimetic locomotion can have both compact structure and multi DOF locomotion. 相似文献