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91.
Antioxidant Properties of Bromocriptine, a Dopamine Agonist 总被引:3,自引:1,他引:2
Toshikazu Yoshikawa† Yukiko Minamiyama Yuji Naito Motoharu Kondo 《Journal of neurochemistry》1994,62(3):1034-1038
Abstract: It has been suggested that free radicals may adversely influence the pathogenesis of Parkinson's disease. We conducted this study to determine whether bro-mocriptine, an agent widely used for treating parkinsonism, possesses antioxidant effects. Bromocriptine scavenged superoxide produced from a superoxide generating system (hypoxanthine-xanthine oxidase) by the spin-trapping method using electron spin resonance. Bromocriptine had a strong scavenging effect on the 5,5-dimethyl-1-pyrroline- N -oxide hydroxide signal produced from Fenton's reaction. Bromocriptine also attenuated the stable free radical diphenyl- p -picrylhydrazyl signal. This drug inhibited the autooxidation of rat brain homogenates in a dose-dependent manner in vitro. Autooxidation of brain homogenates collected from rats treated with bromocriptine (2.5 mg/kg, i.p., daily for 3 days) was significantly reduced as compared with values in untreated rat homogenates. These observations suggest that bromocriptine is a free radical scavenger and a potent antioxidant. 相似文献
92.
Kazuhito Hisatsune Takehiro Iguchi Yuji Haishima Norihiko Tamura Seiichi Kondo 《Microbiology and immunology》1993,37(2):143-147
The chemical properties of a lipopolysaccharide (LPS) isolated from a new O-antigenic form (O13) of Vibrio parahaemolyticus were investigated. The LPS contained glucose, galactose, L -glycero-D -manno-heptose and glucosamine. 2-Keto-3-deoxy-octonate (KDO) was not detected in the LPS by the periodate-thiobarbituric acid test (Weissbach's reaction) under conventional hydrolysis conditions. Instead, phosphorylated KDO (X1 and X2) was found in its strong-acid hydrolysate. This sugar composition was identical to that of V. parahaemolyticus O3, O5 and O11 LPS, indicating that, based on the sugar composition, O13 LPS belongs to Chemotype III to which O3, O5 and O11 belong. In addition, structural study demonstrated the presence of KDO 4-phosphate in its inner-core region. 相似文献
93.
To understand force generation under a wide range of loads, the stepping of single kinesin molecules was measured at loads from −20 to 42 pN by optical tweezers with high temporal resolution. The optical trap has been improved to halve positional noise and increase bandwidth by using 200-nm beads. The step size of the forward and backward steps was 8.2 nm even over a wide range of loads. Histograms of the dwell times of backward steps and detachment fit well to two independent exponential equations with fast (~0.4 ms) and slow (>3 ms) time constants, indicating the existence of a fast step in addition to the conventional slow step. The dwell times of the fast steps were almost independent of the load and ATP concentration, while those of the slow backward steps and detachment depended on those. We constructed the kinetic model to explain the fast and slow steps under a wide range of loads. 相似文献
94.
Koiwai Keiichiro Kondo Hidehiro Hirono Ikuo 《Marine biotechnology (New York, N.Y.)》2023,25(3):488-502
Marine Biotechnology - The classification of cells in non-model organisms has lagged behind the classification of cells in model organisms that have established cluster of differentiation marker... 相似文献
95.
M. Kondo W. E. Finkbeiner J. H. Widdicombe 《In vitro cellular & developmental biology. Animal》1993,29(1):19-24
Summary Tracheal epithelial cells were grown on Nuclepore filters coated with human placental collagen. When grown immersed in medium
containing fetal bovine serum, cells displayed an undifferentiated ultrastructure (no cilia and a cell height of ∼ 10 μm).
Short-circuit current (Isc) was approximately 1/10 that of the native epithelium. By contrast, when grown in hormonally defined, serum-free medium with
an air interface, cells showed Isc equal to or greater than the original tissue, possessed cilia, and had a cell height of ∼ 50 μm. Responses in Isc to mediators were similar to those of the original tissue, but differed from those of dog or human tracheal epithelium. Given
the ready availability and low cost of the native tissues, bovine tracheal cultures grown in serum-free medium with an air
interface should prove useful in studies of airway epithelial physiology. 相似文献
96.
Kyosuke Mushiake Fumiaki Motoyoshi Naomi Kondo Hiroyuki Shimizu Tadao Orii 《Biotherapy》1993,7(2):101-107
Five patients with common variable immunodeficiency treated in our hospital between December 1979 and December 1990 were given six kinds of intravenous immunoglobulin preparations (pepsin treated, S-sulfonated, polyethylene glycol treated, pH4 treated, alkylated, and pH4.25 formulation preparation) for replacement therapy. Duration of the therapy ranged from 7.6 to 11 years. Incidences of fever and acute infections were variable among patients, but no significant differences were seen in the incidences among periods given each preparation. Three cases revealed abnormal pulmonary functions in tests. Adverse reactions were rarely seen in our study periods, and no severe reactions were observed. No significant differences were seen in incidences of adverse reactions. Postinfusion levels of serum complement slightly decreased from preinfusion levels. However, the decrease in complement was not related to any adverse reaction. No long-term complications such as transmission of hepatitis have been observed. Our data suggest that no obvious differences exist between the efficacy and safety of each IVIG preparation. Differences of efficacy of IVIG replacement therapy may be due to the variable pathophysiology of each patient.Abbreviations CVID
common variable immunodeficiency
- IVIG
intravenous immunoglobulin 相似文献
97.
98.
Transport of chimeric proteins that contain a carboxy-terminal targeting signal into plant microbodies 总被引:6,自引:2,他引:4
Makoto Hayashi Masahiro Aoki Akira Kato Maki Kondo Mikio Nishimura 《The Plant journal : for cell and molecular biology》1996,10(2):225-234
Malate synthase is a glyoxysome-specific enzyme. The carboxy-terminal tripeptide of the enzyme is Ser—Arg—Leu (SRL), which is known to function as a peroxisomal targeting signal in mammalian cells. To analyze the function of the carboxy-terminal amino acids of pumpkin malate synthase in plant cells, a chimeric gene was constructed that encoded a fusion protein which consisted of β-glucuronidase and the carboxyl terminus of the enzyme. The fusion protein was expressed and accumulated in transgenic Arabidopsis that had been transformed with the chimeric gene. Immunocytochemical analysis of the transgenic plants revealed that the carboxy-terminal five amino acids of pumpkin malate synthase were sufficient for transport of the fusion protein into glyoxysomes in etiolated cotyledons, into leaf peroxisomes in green cotyledons and in mature leaves, and into unspecialized microbodies in roots, although the fusion protein was no longer transported into microbodies when SRL at the carboxyl terminus was deleted. Transport of proteins into glyoxysomes and leaf peroxisomes was also observed when the carboxy-terminal amino acids of the fusion protein were changed from SRL to SKL, SRM, ARL or PRL. The results suggest that tripeprides with S, A or P at the −3 position, K or R at the −2 position, and L or M at the carboxyl terminal position can function as a targeting signal for three kinds of plant microbody. 相似文献
99.
Hormonal imprinting takes place at the first encounter of the hormone and receptor, and results in a changed binding capacity and reaction of the cell and its progeny generations. The imprinting effect of three amino acids and their oligopeptides is studied using fluorescent-labelled peptides. Glycine and lysine could provoke positive imprinting (increased binding in the progeny generations) for their own peptides, but alanine could not. Mostly positive imprinting was provoked by glycine and lysine peptides for their own peptides of different chain length. The optimal chain length provoking self-imprinting was four for glycine, two for lysine and three for alanine. Except in this case, alanine was neutral or provoked mostly negative imprinting. After reaching the optimal chain length, there is a decline in binding. Evolutionary conclusions are discussed. 相似文献
100.
Nakajima Nobuyoshi; Saji Hikaru; Aono Mitsuko; Kondo Noriaki 《Plant & cell physiology》1995,36(5):919-924
cDNA encoding the plasma membrane H+-ATPase of guard cells ofVicia faba L. was isolated. The clone encoded a 105-kDa polypeptide(956 amino acids) that was 7985% identical in terms ofamino acid sequence to other plant H+-ATPases. High levels ofmRNA explain the high H+-ATPase activity of these plasma membranes. (Received December 24, 1994; Accepted April 12, 1995) 相似文献