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排序方式: 共有508条查询结果,搜索用时 15 毫秒
91.
92.
Benneth Ben-Azu Adegbuyi Oladele Aderibigbe Aya-Ebi Okubo Eneni Abayomi Mayowa Ajayi Solomon Umukoro Ezekiel O. Iwalewa 《Neurochemical research》2018,43(9):1745-1755
Previous studies have revealed that morin (MOR), a neuroactive bioflavonoid, with proven psychotropic and neuroprotective properties reduced schizophrenic-like behaviors in mice. This study further evaluated the ability of MOR to prevent and reverse ketamine-induced schizophrenic-like behaviors and the underlying neurochemical changes and increased oxidative/nitrergic stress in mice. In the preventive protocol, mice received intraperitoneal injection of MOR (100 mg/kg), reference antipsychotic drugs [haloperidol (1 mg/kg), risperidone (0.5 mg/kg)], or saline daily for 14 consecutive days prior to i.p. injection of ketamine (KET) (20 mg/kg/day) from the 8th to the 14th day. In the reversal protocol, the animals received KET or saline for 14 days prior to MOR, haloperidol, risperidone, or saline treatments. Schizophrenic-like behaviors: positive (open-field test), negative (social-interaction test) and cognitive (Y-maze test) symptoms were evaluated. Thereafter, the brain levels of dopamine, glutamate, 5-hydroxytryptamine and acetyl-cholinesterase, as well as biomarkers of oxidative/nitrergic stress were measured in the striatum, prefrontal-cortex (PFC) and hippocampus (HC). Morin prevented and reversed KET-induced hyperlocomotion, social and cognitive deficits. Also, MOR or risperidone attenuated altered dopaminergic, glutamatergic, 5-hydroxytryptaminergic and cholinergic neurotransmissions in brain region-dependent manner. The increased malondialdehyde and nitrite levels accompanied by decreased glutathione concentrations in the striatum, PFC and HC in KET-treated mice were significantly attenuated by MOR or risperidone. Taken together, these findings suggest that the anti-schizophrenic-like activity of MOR may be mediated via mechanisms related to attenuation of neurochemical changes and oxidative/nitrergic alterations in mice. 相似文献
93.
Light emission (chemiluminescence; CL) was observed in the reaction of anthocyanins with tert-butyl hydroperoxide (t-BuOOH) in the presence of acetaldehyde. The intensity of the CL of the anthocyanins was in the order of nasunin > rubrobrassicin > delphinidin > malvin = cyanidin > malvidin, indicating that glucosylation at C-3 and C-5 of the anthocyanin skeleton enhances the CL of the parent compound. CL intensity was enhanced at alkaline pH. The results suggest that the antioxidant effect of anthocyanins on lipid peroxidation, which is observed in the linoleic acid-β-carotene-lipoxcygenase system, is at least partly due to their strong reactivity with hydroperoxides. 相似文献
94.
Hironori Tsuchiya Masaru Sato Hirotsugu Kato Tsutomu Okubo Lekh R. Juneja Mujo Kim 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1997,703(1-2)
Green tea extracts have been suggested to possess a preventive effect against dental caries. A quantitative method for their anticariogenic substances, catechins, was developed to evaluate their concentrations in human saliva after mouthrinsing with green tea extract. Salivary catechins were extracted to the organic phase after forming a complex with diphenylborate and an ion-pair with tetra-n-butylammonium, and then back-extracted to the acidic aqueous phase. The extract was analyzed by high-performance liquid chromatography using diode array detection at absorption wavelengths ranging from 269 to 278 nm. In reversed-phase chromatography by a gradient elution, eight catechins originating from green tea and an internal standard were separated in 15 min without interfering peaks. All the catechins were simultaneously and selectively determined in the concentration range 0.05–25.0 μg/ml. In replicate spiking experiments with standards, the mean recovery ranged between 86 and 99%, and both intra- and inter-assay C.V.s were within 2.3%. When mouthrinsing with an aqueous solution of green tea extract (5.0 mg/ml) containing eight catechins, the quantitative results revealed that each catechin was retained at μg/ml levels in saliva for up to 60 min. 相似文献
95.
S Tanaka T Kobayashi H Tomura M Okubo K Nakanishi J Takeda T Murase 《Hormones et métabolisme》2000,32(9):373-377
We investigated the presence and the function of hepatocyte nuclear factor-1alpha (HNF-1alpha) mutations in 26 Japanese subjects with type 2 diabetes. The subjects were between 20 and 39 years of age on diagnosis and had diabetic first-degree relatives. Two different frameshift mutations were found in 2 subjects (8 %). One novel mutation, T539fsdelC (deletion of C in codon 539 for Thr), is predicted to generate a protein of normal 539 residues at the N-terminus followed by an abnormal 119 amino acid protein. The mutation, P291fsinsC (insertion of C in codon 291 for Pro) should lead to production of a truncated protein of 315 amino acids. Transfection reporter assay using MIN6 and HepG2 cells revealed both mutations to have null function in the transactivation of reporter gene expression. When transfected with wild-type gene, these mutations behaved as dominant-negative regulators in both cells. An equimolar amount of T539fsdelC reduced wild-type activity by approximately 80% in MIN6 cells, while the same concentration of P291fsinsc reduced it by 30%. The sequences responsible for the transactivation activity of HNF-1alpha are confined largely to amino acids 547-628, so that the T539fsdelC mutation, which affects this entire region, replacing amino acids 540-631 with an abnormal 119 amino acid protein, may acquire a potent dominant-negative function. 相似文献
96.
Takumi Okubo Daiki Hayashi Takayuki Yaguchi Yudai Fujita Motoharu Sakaue Takehito Suzuki Atsushi Tsukamoto Ohoshi Murayama Jonathan Lynch Yoko Miyazaki Kazuaki Tanaka Tatsuya Takizawa 《Experimental Animals》2016,65(1):45-51
Valproic acid (VPA) is a widely used antiepileptic drug, which has recently been reported
to modulate the neuronal differentiation of adipose tissue-derived stem cells (ASCs) in
humans and dogs. However, controversy exists as to whether VPA really acts as an inducer
of neuronal differentiation of ASCs. The present study aimed to elucidate the effect of
VPA in neuronal differentiation of rat ASCs. One or three days of pretreatment with VPA (2
mM) followed by neuronal induction enhanced the ratio of immature neuron marker
βIII-tubulin-positive cells in a time-dependent manner, where the majority of cells also
had a positive signal for neurofilament medium polypeptide (NEFM), a mature neuron marker.
RT-PCR analysis revealed increases in the mRNA expression of microtubule-associated
protein 2 (MAP2) and NEFM mature neuron markers, even
without neuronal induction. Three-days pretreatment of VPA increased acetylation of
histone H3 of ASCs as revealed by immunofluorescence staining. Chromatin
immunoprecipitation assay also showed that the status of histone acetylation at H3K9
correlated with the gene expression of TUBB3 in ASCs by VPA. These
results indicate that VPA significantly promotes the differentiation of rat ASCs into
neuron-like cells through acetylation of histone H3, which suggests that VPA may serve as
a useful tool for producing transplantable cells for future applications in clinical
treatments. 相似文献
97.
Context: Plasma liver-specific mRNAs are useful biomarkers of hepatotoxicity in rats.Objective: To investigate the potential application of liver-specific mRNAs as biomarkers for liver injury in humans.Methods: We determined the plasma levels of liver-specific mRNAs by real-time qRT-PCR in healthy donors and patients with liver injury.Results: Plasma levels of albumin (ALB) and apolipoprotein H (APOH) mRNAs increased in patients with elevated serum alanine aminotransferase. These mRNAs also increased in plasma after transcatheter arterial chemoembolization, which induces specific injury to liver.Conclusions: We demonstrated the potential application of plasma ALB and APOH mRNAs as clinical biomarkers for liver injury. 相似文献
98.
Subgroups of type A blood, named A1, A2, and A1-A2 intermediate (Aint), are specifically characterized by their peculiar A alleles and have their own A1-, A2- or Aint-forms of alpha-N-acetyl-D-galactosaminyltransferase (A-transferase). It is known, however, that certain type A2B persons exhibit A1-transferase. The reason may be an unusual alpha-galactosyltransferase (B-transferase). This strong B-transferase competes with A-transferase for the substrate, H antigen, so as to decrease the A and H antigens on the red cells. We studied this blood group over three generations and found that the strong B-transferase is, in fact, inherited with the B gene and is dominant over normal B-transferase. In AB blood groups in Tokyo, the frequency of people with a strong B-transferase is 5% for A1B and 22% for A2B. This enzyme does not always cause weak H or A antigens. 相似文献
99.
H. Hachisuka H. Nomura O. Mori S. Nakano K. Okubo M. Kusuhara M. Karashima E. Tanikawa M. Higuchi Y. Sasai 《Cell and tissue research》1990,260(1):207-210
Summary The epidermis shows a distinctive pattern of differentiation wherein keratinocytes proliferate in the basal cell layer and mature into spinous and granular cells. Using a discontinuous density-gradient centrifugation method, guinea-pig keratinocytes were separated into high (HDF), intermediate (IDF), and low (LDF) density fractions. Morphological and flow cytometrical observations demonstrated that HDF, IDF, and LDF were basal, spinous, and granular cell-rich fractions, respectively. Membrane fluidity of the fractionated keratinocytes was measured by diphenylhexatriene fluorescence polarization. Polarization (p)-value of keratinocytes was negatively correlated with temperature. At each temperature, HDF cells showed a lower p-value than IDF or HDF cells except at 40° C. Since a low p-value indicates a high degree of Brownian motion, membrane fluidity is higher in basal cells and lower in spinous and granular cells. Our results indicate that membrane fluidity of guinea-pig keratinocytes decreases during their maturation. 相似文献
100.
Isolation and Properties of Suppressor-Sensitive Mutants of Bacillus subtilis Bacteriophage SPO2 总被引:11,自引:8,他引:3
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Suppressor-sensitive mutants of Bacillus subtilis phage SPO2 were isolated and classified into 18 cistrons. A linear genetic map was constructed. The genes controlling early functions of phage development were clustered near the CI gene which may produce phage repressor. 相似文献