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21.

Aromatherapy with essential oils is one of the most popular complementary medical tools for improving sleep quality. However, only a few reports have objectively measured the effects of essential oils on sleep. Here, we used objective and subjective measures to analyze the effects of the essential oils of lavender (Lavandula angustifolia) and sweet orange (Citrus sinensis) on the sleep quality of healthy university students. The participants were monitored for 15 consecutive nights as they inhaled lavender oil and sweet orange oil, in a crossover design. Their sleep was monitored objectively by actigraphy, and total sleep time (TST), sleep efficiency, sleep latency, and wake after sleep onset (WASO) were analyzed. Their sleep was analyzed subjectively using Oguri–Shirakawa–Azumi (OSA) sleep inventory scores. Inhalation of an essential oil improved sleep measures only in participant whose sleep quality was poor in the control condition. Lavender seemed more effective than sweet orange in objective measures, especially in improving sleep latency. In the subjective sleep analysis, the essential oils improved sleep maintenance, dreaming, and sleep length in subjects who had poor sleep quality. Sweet orange seemed more effective than lavender in the subjective sleep measures. The difference between the two oils suggests that expectancy bias had little effect on the hypnotic effect of lavender on objective sleep. Although no obvious effect was observed in good sleepers, the inhalation of lavender oil could be effective for helping poor sleepers improve objective sleep quality.

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22.
The effect of concanavalin A and ionophore A23187 on leucine uptake by human peripheral lymphocytes has been examined. Preincubation of the cells with 32 micrograms/ml concanavalin A or 0.1 microM A23187 increased leucine uptake by 67% and 100%, respectively. Both concanavalin A and A23187 could, within 2 min, induce a more than 2-fold increase in the cytoplasmic free Ca2+ concentration ([Ca2+]i). This increase by concanavalin A was completely blocked by the addition of 0.1 mM 8-(N,N-diethylamino)-octyl-3,4,5-trimethoxybenzoate (TMB-8) to incubation medium; TMB-8 partially blocked the action of A23187. The stimulation of leucine uptake by concanavalin A and A23187 was strongly inhibited by the presence of TMB-8 in the medium, whereas the basal uptake was not affected by this intracellular Ca2+ antagonist. Amiloride did not inhibit the stimulation of leucine uptake by concanavalin A. The concanavalin A- and A23187-induced elevation of [Ca2+]i was accompanied by membrane hyperpolarization. Concanavalin A-stimulated leucine uptake was greatly inhibited by the presence of an excess of 2-aminobicyclo[2.2.1]heptane-2-carboxylic acid. These results indicate that the increase in [Ca2+]i may function as a signal of the stimulation by mitogen of leucine uptake mediated by system L, finally inducing membrane hyperpolarization in human lymphocyte.  相似文献   
23.
The growth rate of tumors should be assessed in terms of both tumor cell proliferation and death. The former is considered to be determined by growth fraction and cell-cycle time, whereas the latter is mainly determined by apoptosis, especially in tumors with a low level of necrosis. While most hepatocellular carcinomas (HCCs) in a relatively early stage contain only a small amount of necrosis, the growth rate supposedly depends mainly on growth fraction, cell-cycle time, and apoptosis. However, their quantitative relationship remains unknown. We have derived a novel theoretical formula for determining this relationship in nonnecrotic HCC, using Ki-67-positive index, apoptotic score, and a correction factor, all calculable by histological assessment without injecting labeling agents. Furthermore, we confirmed the reliability of this formula, using a xenograft model of human HCC with less than 15% necrosis. In this model the values of cell-cycle time calculated from the formula were very close to those estimated by a conventional double-labeling method and showed high correlations. Since our novel formula can clarify the cell kinetics without cumbersome labeling procedures, it is expected to be clinically applicable to HCC with a small portion of necrosis, using the radiographically measured growth rate and the histologically assessed cell kinetic parameters.  相似文献   
24.
Energy metabolism, oxygen consumption rate (VO2), and respiratory quotient (RQ) in mice were monitored continuously throughout 12:12-h light-dark cycles before, during, and after time-restricted feeding (RF). Mice fed ad libitum showed robust daily rhythms in both parameters: high during the dark phase and low during the light phase. The daily profile of energy metabolism in mice under daytime-only feeding was reversed at the beginning of the first fasting night. A few days after daytime-only feeding began, RF also reversed the circadian core body temperature rhythm. Moreover, RF for 6 consecutive days shifted the phases of circadian expression patterns of clock genes in liver significantly by 8-10 h. When mice were fed a high-fat (HF) diet ad libitum, the daily rhythm of RQ dampened day by day and disappeared on the sixth day of RF, whereas VO2 showed a robust daily rhythm. Mice fed HF only in the daytime had reversed VO2 and RQ rhythms. Similarly, mice fed HF only in the daytime significantly phase shifted the clock gene expression in liver, whereas ad libitum feeding with HF had no significant effect on the expression phases of liver clock genes. These results suggested that VO2 is a sensitive indicator of entrainment in the mouse liver. Moreover, physiologically, it can be determined without any surgery or constraint. On the basis of these results, we hypothesize that a change in the daily VO2 rhythm, independent of the energy source, might drive phase shifts of circadian oscillators in peripheral tissues, at least in the liver.  相似文献   
25.
Leucine-proton cotransport system in Chang liver cell   总被引:1,自引:0,他引:1  
The stimulatory effect of an inward H+ gradient on the Na+-independent L-leucine uptake by the plasma membrane vesicles from Chang liver cells (Mohri, T., Mitsumoto, Y., and Ohyashiki, T. (1983) Biochem. Int. 7, 159-167) has been shown to be due to the increase of the Km value without changing the Vmax value in the transport kinetics. The uptake of leucine by the vesicles is accompanied by intravesicular acidification, and a stimulated uptake of leucine by the countertransport with a high concentration of leucine in the vesicles enhances the acidification. All of these uptakes of leucine and proton and their stimulations are amplified by imposing an inward proton gradient. These results suggest appreciably different affinities of proton for the leucine transport carrier in the inner and outer sides of the plasma membrane. A rapid decrease in the cytoplasmic pH was observed only in the first minute of incubation of intact cells with leucine in Na+-containing medium. But the leucine-dependent decrease of the cytoplasmic pH persisted longer when either Na+ in the medium was replaced by choline or amiloride was present along with Na+. Addition of amiloride to Na+-containing medium was inhibitory on the leucine uptake of cells, without effect on the early phase of glycine uptake. We conclude that Chang liver cells are provided in their plasma membrane with an amino acid-H+ cotransport system, and this is coupled to the amiloride-sensitive Na+/H+ exchange system.  相似文献   
26.
Effects of perfluorocarboxylic acids (PFCAs) on proportions of oleic acid and cis-vaccenic acid through acyl-CoA chain elongation systems have been studied in the liver of rats. Administration of PFCAs caused a significant increase in palmitoyl-CoA chain elongation activity while these chemicals did not affect palmitoleoyl-CoA chain elongation activity in vivo.Condensation for both palmitoyl-CoA and palmitoleoyl-CoA were inhibited by PFCAs in vitro at the concentrations, which were physiologically found in the liver of rats treated with the PFCAs. Δ9 Desaturase, which catalyzes both stearoyl-CoA desaturation and palmitoyl-CoA desaturation, was induced by the treatments of rats with the PFCAs. The administration of the PFCAs to rats caused a marked increase in proportion of oleic acid, while that of cis-vaccenic acid was not affected at all. These results strongly suggest that the induced palmitoyl-CoA chain elongation by PFCAs, which exist in the liver, effectively produces oleic acid in concert with the induced stearoyl-CoA desaturase, but the inhibitory effects of PFCAs on either palmitoyl-CoA chain elongation or palmitoleoyl-CoA chain elongation are not crucial for the formation of the elongated fatty acids in vivo.  相似文献   
27.
The HNK-1 carbohydrate is expressed on various cell adhesion molecules in the nervous system and is suggested to play a role in cell-cell and cell-substrate interactions. Here we describe the isolation of a cDNA encoding human glucuronyltransferase (GlcAT-P), which is a key enzyme in the biosynthesis of the HNK-1 carbohydrate. The primary structure deduced from the cDNA sequence predicted a type II transmembrane protein of 334 amino acids. Human GlcAT-P was 98.2% identical with rat GlcAT-P in amino acid sequence, the exception being the length of the cytoplasmic tail. Northern blot analysis indicated that human GlcAT-P is expressed mainly in the brain. There is a single copy of the human GlcAT-P gene (HGMW-approved symbol B3GAT1), and it was mapped to chromosome 11q25.  相似文献   
28.
We have demonstrated simultaneous measurement of the membrane potential and cytoplasmic free Ca2+ concentration ([Ca2+]i) by utilizing a dual-laser flow cytometer in embryonic rat hippocampal cell suspensions. Veratrine, a Na+ channel activator, induced both membrane depolarization and elevation of [Ca2+]i. These actions of veratrine were all reversed by the presence of tetrodotoxin (TTX). These findings suggest that Na+ channels are functionally expressed in the cells and the activation of Na+ channels increases [Ca2+]i. The usefulness of the flow cytometric analysis in elucidating the expression of membrane functions in the embryonic central nervous systems (CNS) is discussed.  相似文献   
29.
The adult form of Tay-Sachs disease, adult GM2 gangliosidosis, is an autosomal recessive neurological disorder caused by a partial deficiency of beta-hexosaminidase A. We had previously identified, in Ashkenazi-Jewish adult GM2 gangliosidosis patients, a Gly269----Ser mutation in the beta-hexosaminidase alpha-subunit. All of the Ashkenazi patients were found to be compound heterozygotes with an allele containing the Gly269----Ser mutation together with one of the Ashkenazi infantile Tay-Sachs alleles. We have now found the same Gly269----Ser mutation in six adult GM2 gangliosidosis patients from four different non-Jewish families. Genomic DNA from three of the patients, two of whom were brothers, exhibited a hybridization pattern consistent with homozygosity for the Gly269----Ser mutation. The remaining non-Jewish patients were compound heterozygotes of the Gly269----Ser mutation together with an unidentified alpha-subunit mutation. The results demonstrate that individuals homozygous for the Gly269----Ser change can be clinically affected. The same Gly269----Ser mutation in both the Ashkenazi and non-Jewish patients may be the result of a common ancestor, given that the ancestry of these non-Jewish patients, like the Ashkenazim, can be traced to eastern Europe.  相似文献   
30.
During meiosis, double-strand breaks (DSBs) lead to crossovers, thought to arise from the resolution of double Holliday junctions (HJs) by an HJ resolvase. In Schizosaccharomyces pombe, meiotic crossovers are produced primarily through a mechanism requiring the Mus81-Eme1 endonuclease complex. Less is known about the processes that produces crossovers during the repair of DSBs in mitotic cells. We employed an inducible DSB system to determine the role of Rqh1-Top3 and Mus81-Eme1 in mitotic DSB repair and crossover formation in S. pombe. In agreement with the meiotic data, crossovers are suppressed in cells lacking Mus81-Eme1. And relative to the wild type, rqh1Delta cells show a fourfold increase in crossover frequency. This suppression of crossover formation by Rqh1 is dependent on its helicase activity. We found that the synthetic lethality of cells lacking both Rqh1 and Eme1 is suppressed by loss of swi5(+), which allowed us to show that the excess crossovers formed in an rqh1Delta background are independent of Mus81-Eme1. This result suggests that a second process for crossover formation exists in S. pombe and is consistent with our finding that deletion of swi5(+) restored meiotic crossovers in eme1Delta cells. Evidence suggesting that Rqh1 also acts downstream of Swi5 in crossover formation was uncovered in these studies. Our results suggest that during Rhp51-dependent repair of DSBs, Rqh1-Top3 suppresses crossovers in the Rhp57-dependent pathway while Mus81-Eme1 and possibly Rqh1 promote crossovers in the Swi5-dependent pathway.  相似文献   
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