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61.
Yoriko Masuda Satoshi Haramizu Kasumi Oki Koichiro Ohnuki Tatsuo Watanabe Susumu Yazawa Teruo Kawada Shu-ichi Hashizume Tohru Fushiki 《Journal of applied physiology》2003,95(6):2408-2415
Capsiate is a nonpungent capsaicin analog, a recently identified principle of the nonpungent red pepper cultivar CH-19 Sweet. In the present study, we report that 2-wk treatment of capsiate increased metabolic rate and promoted fat oxidation at rest, suggesting that capsiate may prevent obesity. To explain these effects, at least in part, we examined uncoupling proteins (UCPs) and thyroid hormones. UCPs and thyroid hormones play important roles in energy expenditure, the maintenance of body weight, and thermoregulation. Two-week treatment of capsiate increased the levels of UCP1 protein and mRNA in brown adipose tissue and UCP2 mRNA in white adipose tissue. This dose of capsiate did not change serum triiodothyronine or thyroxine levels. A single dose of capsiate temporarily raised both UCP1 mRNA in brown adipose tissue and UCP3 mRNA in skeletal muscle. These results suggest that UCP1 and UCP2 may contribute to the promotion of energy metabolism by capsiate, but that thyroid hormones do not. 相似文献
62.
Tadayuki Miyamoto Susumu Kagawa Kouki Kitagawa Shiroh Futaki Hiromichi Yokoi Yoshihiro Tsuruo Kazunori Ishimura 《Histochemistry and cell biology》1996,105(2):101-109
We immunohistochemically studied the localization of 5-reductase type 1 in combination with androgen receptor (AR) expression in individual lobes of the prostates of intact and castrated rats. In the normal rat prostate, 5-reductase was localized in the cytoplasm of most epithelial cells in the ventral, dorsal, and lateral type 1 (L1) lobes. Epithelial cells of lateral type 2 (L2) lobes were negative for 5-reductase. AR was present in the nuclei of all epithelial and stromal cells throughout the prostate. The number of 5-reductase-immunoreactive cells rapidly decreased in the ventral and L1 lobes after castration, whereas many positive cells remained in the dorsal lobe even at 4 weeks after castration. AR immunostaining was lost in the ventral, dorsal, and L1 lobes at 1 week after castration, but remained in the L2 lobe of 4-week-castrated rats. Electron microscopic immunocytochemistry showed that 5-reductase was exclusively localized in the rough endoplasmic reticulum membranes and that there were no distinct structural differences between the positively and negatively stained epithelial cells. These findings suggested that the expression of 5-reductase type 1 in the epithelial cell is heterogeneous within and among the individual lobes of the rat prostate, and does not correspond to AR expression. 相似文献
63.
The Nucleotide Sequence of Human Acylamino Acid-Releasing Enzyme 总被引:3,自引:0,他引:3
Mitta Masanori; Ohnogi Hiroshi; Mizutani Shigetoshi; Sakiyama Fumio; Kato Ikunoshin; Tsunasawa Susumu 《DNA research》1996,3(1):31-35
The nucleotide sequence of a cDNA coding for the human acylaminoacid-releasing enzyme (AARE, also known as acylpeptide hydrolase)[EC 3.4.19.1] subunit has been determined. The amino acid sequenceof human AARE subunit deduced from its cDNA nucleotide sequenceshowed a high degree of identity (91.5%) with both the correspondingproteins from the pig and the rat. The AARE cDNA shows 99.2%identity with a 3.3 kb cDNA transcribed from a locus (DNF15S2)on the short arm of human chromosome 3, whose deletion is associatedwith small cell lung cancer, taking into consideration thatthe sequence of the 3.3-kb cDNA previously reported was causedby misreading. 相似文献
64.
Susumu Hayashi 《Journal of Ethology》1995,13(1):57-61
Male mice (Mus domesticus) were reared in groups of 2 or 3 males until 13 weeks of age. They then fought each other every third day. Aggressiveness
was quantified on the basis of the frequency of aggressive behavior shown by each mouse in each match. The data suggest that
there was positive correlation between the levels of aggression of the cage-mates in the 2-male group. Significant correlations
also existed between the most doninant and subordinate males and between the secondary and the subordinate males in the 3-male
group. The aggressiveness of male mice correlated positively with that of their cage-mates from 65 to 91 days of age but did
not correlate with that of the cage-mate living together from 35 to 61 days of age. 相似文献
65.
Mercurial-sensitive water transport in barley roots 总被引:16,自引:0,他引:16
Masashi Tazawa Eiji Ohkuma Mineo Shibasaka Susumu Nakashima 《Journal of plant research》1997,110(4):435-442
An isolated barley root was partitioned into the apical and basal part across the partition wall of the double-chamber osmometer.
Transroot water movement was induced by subjecting the apical part to a sorbitol solution, while the basal part with the cut
end was in artificial pond water. The rate of transroot osmosis was first low but enhanced by two means, infilitration of
roots by pressurization and repetition of osmosis. Both effects acted additively. The radial hydraulic conductivity (Lpr) was calculated by dividing the initial flow rate with the surface area of the apical part of the root, to which sorbitol
was applied, and the osmotic gradient between the apical and basal part of the root. Lpr which was first 0.02–0.04 pm s−1 Pa−1 increased up to 0.25–0.4 pm s−1 Pa−1 after enhancement. Enhancement is assumed to be caused by an increase of the area of the plasma membrane which is avallable
to osmotic water movement. The increased Lpr is in the same order of magnitude as the hydraulic conductivity (Lp) of epidermal and cortical cells of barley roots obtained
by Steudie and Jeschke (1983). HgCl2, a potent inhibitor of water channels, suppressed Lpr of non-infiltrated and infiltrated roots down to 17% and 8% of control values, respectively. A high sensitivity of Lpr to HgCl2 suggests that water channels constitute the most conductive pathway for osmotic radial water movement in barley roots. 相似文献
66.
Masahiro Sakaguchi Sakae Inouye Yuichi Takahashi Susumu Kutagiri Hiroshi Yasueda 《Aerobiologia》1995,11(4):265-268
We examined the kinetics of airborne levels of mite allergen particles in a house by combined use of an indoor Burkard air
sampler and immunoblotting. Airborne mite allergens collected on the Burkard sampling tape were transferred onto a nitrocellulose
membrane, reacted with mouse monoclonal anti-mite allergen (Der pI) antibody, then treated with alkaline phosphatase conjugated anti-mouse IgG. Finally, the blotted allergen on the membrane
was reacted with BCIP/NBT phosphatase, and purple spots visible by the naked eye were produced. The shape of the spots was
observed under a microscope, and the spot area was measured by an image processor. This technique might be useful for analyzing
the behavior of airborne allergen particles in indoor environments. 相似文献
67.
A new system was designed to detect staphylococcal exfoliative toxin A (ETA) and B (ETB) genes by the polymerase chain reaction (PCR). The primer pairs for the ETA gene (eta) were 20 and 20-mer, and its PCR product was a 741-bp eta fragment, while the primer pairs for the ETB gene (etb) were also 20 and 20-mer, and its PCR product was a 629-bp etb fragment. When these primers were simultaneously used in the PCR, the two types of ET were clearly detected as two bands in an ETA and ETB double-producer using only one colony within 3 hr. We examined 66 strains of Staphylococcus aureus isolated from patients with staphylococcal scalded skin syndrome (SSSS) and compared the results obtained by ELISA and PCR. The same results were obtained for 56 of the strains, i.e., 30 strains were ETA producers, 20 strains were ETB producers, and 6 strains were double-producers. However, positive results were obtained for 5 of the 10 non-ET-producing strains. Two of these strains were judged by PCR as ETA producers and three as ETB producers. Thus, PCR is very sensitive and rapid in detecting ETA and ETB gene fragments in colonies isolated from patients with SSSS. 相似文献
68.
We studied thein vitro activation of aflatoxin B1 (B1) by microsomes and its inactivation by the cytosol of various quail and hamster organs, using B1-DNA binding as an index. The microsomal activity of the liver to bind B1 to DNA was not largely different between the two species and was higher than that of the other organs examined in either species. The microsomal activity of the kidney and lung was very low in the quail compared with the hamster, indicating the very small contribution of the lung and kidney microsomes to the activation of B1 in birds. Only the hamster liver cytosol showed strong inhibition of microsome-mediated B1-DNA binding. 相似文献
69.
The signal processing through a chain of phosphorylation-dephosphorylations mediated by a pair of enzymes, Ca2+/calmodulin-dependent protein kinase II and the associated phosphatase, is formulated as a non-autonomous dynamical system
in the framework of non-autocatalytic, intraholoenzyme reaction dynamics. A classification of switching characteristics of
the system is made in the parameter space comprising the three controllable system parameters: an input-pulse intensity and
initial concentrations of the two associated enzymes. It is found that a region of parameter space exists termed the transition
zone, that exhibits a quasi-switching behaviour characterized by a signal storage time being prolonged by more than several
orders of magnitude (104 times in certain cases) for the increase of two orders of magnitude in the input signal intensity. The effect of alterations
of certain rate constants on the quasi-switching property is explored. It is numerically demonstrated that the Ca2+/calmodulin-dependent kinase II-related phosphatase is the most important key enzyme for regulating the signal storage time.
Received: 25 April 1994/Accepted in revised form: 16 December 1994 相似文献
70.
Alcohol and aldehyde dehydrogenase genotypes and drinking behavior of Chinese living in Shanghai 总被引:12,自引:0,他引:12
Taro Muramatsu Wang Zu-Cheng Fang Yi-Ru Hu Kou-Bao Yan Heqin Koichi Yamada Susumu Higuchi Shoji Harada Hiroaki Kono 《Human genetics》1995,96(2):151-154
Alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH), the principal enzymes responsible for oxidative metabolism of ethanol, exist in multiple, genetically determined molecular forms. Widely different kinetic properties in some of these isozymes account for the individual differences in alcohol sensitivity. In this study we used the polymerase chain reaction/restriction fragment length polymorphism method to determine the genotypes of the ADH2 and ALDH2 loci of alcoholic and nonalcoholic Chinese living in Shanghai. We also investigated the subjects' drinking patterns by means of semistructured interviews. The alcoholics had significantly lower frequencies of the ADH22 and ALDH22 alleles than did the nonalcoholics, suggesting the inhibitory effects of these alleles for the development of alcoholism. In the nonalcoholic subjects, ADH22 had little, if any, effect, despite the significant effect of the ALDH22 allele in decreasing the alcohol consumption of the individual. Taken together, these results fit the proposed hypothesis for the development of alcoholism, i.e., drinking behavior is greatly influenced by the individual's gentoypes of alcohol-metabolizing enzymes, and the risk of becoming alcoholic is proportionate with the ethanol consumption of the individual. 相似文献