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Karpova NN Pickenhagen A Lindholm J Tiraboschi E Kulesskaya N Agústsdóttir A Antila H Popova D Akamine Y Bahi A Sullivan R Hen R Drew LJ Castrén E 《Science (New York, N.Y.)》2011,334(6063):1731-1734
Antidepressant drugs and psychotherapy combined are more effective in treating mood disorders than either treatment alone, but the neurobiological basis of this interaction is unknown. To investigate how antidepressants influence the response of mood-related systems to behavioral experience, we used a fear-conditioning and extinction paradigm in mice. Combining extinction training with chronic fluoxetine, but neither treatment alone, induced an enduring loss of conditioned fear memory in adult animals. Fluoxetine treatment increased synaptic plasticity, converted the fear memory circuitry to a more immature state, and acted through local brain-derived neurotrophic factor. Fluoxetine-induced plasticity may allow fear erasure by extinction-guided remodeling of the memory circuitry. Thus, the pharmacological effects of antidepressants need to be combined with psychological rehabilitation to reorganize networks rendered more plastic by the drug treatment. 相似文献
64.
Noboru SASAKI Yoshinori IKENAKA Yumiko INOUE Takahiro ICHISE Noriyuki NAGATA Mayumi ISHIZUKA Syouta MM NAKAYAMA Kensuke NAKAMURA Mitsuyoshi TAKIGUCHI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(4):648
Measurement of urinary metanephrines in spot samples is used for the diagnosis of canine pheochromocytoma (PC). We describe a simple analytical method based on liquid chromatography tandem mass spectrometry (LC-MS/MS) for measuring free metanephrine (MN) and normetanephrine (NMN) in spot urine samples. Using the developed method, we evaluated the stability of urinary free-MN and free-NMN at various storing conditions. In addition, we assessed the feasibility of urinary free-MN and -NMN measurement for diagnosing PC. Urine samples were mixed with stable isotope internal standards and thereafter purified by ultrafiltration. The purified samples were analyzed by LC-MS/MS in the multiple reaction monitoring mode after separation on a multimode octa decyl silyl column. The coefficient of variation of free-MN and -NMN measurement was 7.6% and 5.5%, respectively. The linearity range was 0.5–10 µg/l for both analytes. Degradation was less than 10% for both analytes under any of the storage conditions. The median free-NMN ratio to creatinine of 9 PC dogs (595, range 144–47,961) was significantly higher (P<0.05) than that of 13 dogs with hypercortisolism (125, range 52–224) or 15 healthy dogs (85, range 50–117). The developed method is simple and may not require acidification of spot urine. The results of this preliminary retrospective study suggest that the measurement of urinary free metanephrines is a promising tool for diagnosing canine PC. 相似文献
65.
Alternaria mycotoxins in weathered wheat from China 总被引:1,自引:0,他引:1
This is the first report of the natural occurrence of Alternaria mycotoxins in Chinese wheat. Wheat kernels were significantly invaded by Alternaria species, mostly A. alternata, with an average infection frequency of 87.3%. A total of 22 samples of weathered wheat kernels from the 1998 crop, representing three locations in the suburbs of Beijing, China, were examined for the presence of Alternaria mycotoxins by high-performance liquid chromatography. Alternariol (AOH) was detected in 20 of 22 samples ranging between 116 and 731 microgram/kg (mean = 335 microgram/kg) and alternariol methyl ether (AME) at a mean level of 443 microgram/kg (range = 52-1426 microgram/kg) in 21 samples. The presence of tenuazonic acid (TA), a major Alternaria toxin in terms of quantity, was detected in all samples analyzed at an average concentration of 2419 microgram/kg with a maximum of 6432 microgram/kg. All samples were free from altertoxin I and altenuene. Samples with high levels of AOH and AME also contain a high level of TA. There was significant linear regression of correlations between the levels of AOH over AME (r = 0.850) and total benzopyrone derivatives (AOH + AME) over TA (r = 0.796). 相似文献
66.
Adachi M Okuda E Kaneda Y Hashimoto A Shutov AD Becker C Müntz K Utsumi S 《Journal of agricultural and food chemistry》2003,51(16):4633-4639
The constituent subunits of seed storage protein 11S globulin have two disulfide bonds that are common among 11S globulins from legume and nonlegume seeds. In the case of the A1aB1b subunit of soybean 11S globulin, glycinin, Cys12-Cys45 and Cys88-Cys298 are observed by X-ray crystallography. The significance of these two disulfide bonds for structural stability was investigated by mutagenesis of Cys12 to Gly and of Cys88 to Ser. The disulfide bond-deficient mutants C12G and C88S could form the correct conformations identical to that of the wild-type proglycinin except in the vicinities of the mutation sites C12 and C88 as shown by their crystal structures. Thermal stability monitored by differential scanning calorimetry of the mutants indicated that the contribution of these disulfide bonds to the thermal stability of proglycinin A1aB1b is low, although there is a small difference in the extent of the contribution between the two disulfide bonds (Cys12-Cys45 > Cys88-Cys298). The contribution of Cys88-Cys298 to the resistance of proglycinin A1aB1b to proteinase digestion is higher than that of Cys12-Cys45. Possible effects of structure on the different properties of C12G and C88S are discussed. 相似文献
67.
Distinct regional profiles of trace element content in muscle of Japanese eel Anguilla japonica from Japan, Taiwan, and China 总被引:1,自引:0,他引:1
Trace element distribution patterns were examined in Japanese eel from five Asian regions for the purpose of identifying the
elements and patterns that could be used to determine provenance. Distinctive patterns were found in eels from the Japanese
prefectures of Miyazaki, Kagawa, and Shizuoka, and from Taiwan and China. The levels of six trace elements, selenium, mercury,
copper, manganese, zinc, and arsenic, in muscle tissue varied among eels of different origins, and factorial analysis of the
elemental patterns showed that Factor 1 was attributable to selenium and mercury levels and Factor 2 to zinc and copper levels.
Multivariate analysis showed that the patterns of elemental composition in fish muscle were mainly differentiated by these
two factors. 相似文献
68.
Takehiko?Yokoyama Yumiko?Tanaka Minoru?Sato Nobuhiro?Kan-No Toshiki?Nakano Toshiyasu?Yamaguchi Eizoh?NagahisaEmail author 《Fisheries Science》2005,71(4):924-930
ABSTRACT: In this paper, the authors report the detection of alanine racemase activity in the marine diatom Thalassiosira sp. Since the Thalassiosira sp. was cultured under germ-free conditions, it appeared that D-alanine was not derived from bacteria but was produced through catalysis by algal alanine racemase. The rate of conversion of L-alanine to D-alanine was approximately the same as that for the reverse reaction, and the enzyme catalyzed the equilibration of the D- and L-forms. The crude enzyme preparation obtained from the cells at the stationary phase of the growth cycle had an optimal pH of approximately 9.5. The Lineweaver–Burk analysis showed that the K m for D- and L-alanine was 16.5 mM and 29.4 mM, respectively. It appears that the enzyme is highly specific for D- or L-alanine because it does not catalyze the racemization of other amino acids. In addition, after gel filtration, the enzyme did not require exogenous pyridoxal 5'-phosphate (PLP) for its activity, however, the effects of several chemicals suggest that the enzyme may be PLP-dependent. The enzyme is more similar to that found in invertebrates when compared with that found in bacteria. This is the first report on the occurrence of alanine racemase activity in the microalga Thalassiosira sp. 相似文献
69.
ABSTRACT: The distribution of mercury in the muscle and other tissues was determined in 23 species of fishes and invertebrates. This study reveals species-specific patterns of mercury accumulation in the muscle of tuna and alfonsino. Consistently high levels of total mercury were found in Beryx splendens (0.78 ± 0.56 µg/g), Atlantic Thunnus thynnus (0.42 ± 0.06 µg/g), Pacific T. thynnus (0.59 ± 0.34 µg/g), Thunnus obesus (0.98 ± 0.34 µg/g), Makaira nigricans (0.56 ± 0.05 µg/g), Tetraptrus audax (0.51 ± 0.08 µg/g), and Xiphias gladius (0.47 ± 0.24 µg/g). Other fish species had lower levels of total mercury or methylmercury in muscle than the maximum permitted level of mercury in fish in Japan (0.4 µg/g). Total mercury and methylmercury levels in the muscles of T. thynnus , T. obesus, and B. splendens were closely correlated with body weight. 相似文献
70.
Makoto Ueno Yumiko Kumura Kana Ueda Junichi Kihara Sakae Arase 《Journal of General Plant Pathology》2011,77(3):209-213
In leaves pretreated with an indole derivative [indole-3-acetic acid (IAA) tryptamine, or tryptophan], blast lesion formation
was suppressed compared to those treated with distilled water (DW) as a control. Phenylalanine ammonia-lyase (PAL) activity
and PAL expression were significantly enhanced in the IAA- or tryptophan-pretreated leaves, but not in tryptamine-pretreated leaves.
This induction of resistance was inhibited by pretreatment with a PAL inhibitor, α-aminooxyacetic acid, in IAA- and in tryptophan-treated
leaves, but not in tryptamine-treated leaves. This study strongly shows that the indole derivatives IAA tryptamine and tryptophan
can enhance a disease resistance mechanism that is supported by different metabolic pathways. 相似文献