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21.
S. Oh-ishi Takako Kizaki Tomomi Ookawara Koji Toshinai Shukoh Haga Fujio Karasawa Tetsuo Satoh Naokazu Nagata L. L. Ji Hideki Ohno 《Pflügers Archiv : European journal of physiology》1998,435(6):767-774
The aim of the current study was to elucidate the synergism of dietary calcium restriction and exhaustive exercise in the
antioxidant enzyme system of rat soleus muscle, and to investigate the involvement of neutrophils in exercise-induced muscle
damage. Forty-eight male Wistar rats were assigned to the following groups: control (C) or calcium-restricted [1 month (1 M)
or 3 months (3 M)]. Each group was subdivided into acutely exercised or non-exercised groups. Soleus muscle from each rat
was analysed to determine the levels of antioxidant enzymes [Mn-superoxide dismutase (SOD), Cu,Zn-SOD, glutathione peroxidase
(GPX), and catalase (CAT)]. Dietary calcium restriction resulted in calcium deficiency and upregulated the antioxidant enzymes
examined except GPX. Conversely, exhaustive exercise significantly decreased GPX and CAT, but not SODs activities in the calcium-restricted
(1 M and/or 3 M) rats. Contents of immunoreactive Mn-SOD and Cu,Zn-SOD were only increased in the 3 M rats. During calcium
restriction, the mRNA expression of both forms of SOD showed initial upregulation, followed by downregulation. Exhaustive
exercise significantly increased the mRNA expressions only in the 3 M rats. Moreover, exhaustive exercise markedly increased
myeloperoxidase activity in soleus muscles from the 1 M and 3 M rats compared with the C rats, and significantly enhanced
the ability of neutrophils to generate superoxide in the 3 M rats. The results demonstrate that dietary calcium restriction
upregulates certain antioxidant enzyme activities in rat soleus muscle, indicating an enhanced resistance to potential increases
in intracellular reactive oxygen species. The results also suggest that exhaustive exercise may cause oxidative damage in
soleus muscle of calcium-deficient rats through the activation of neutrophils.
Received: 4 August 1997 / Received after revision: 29 September 1997 / Accepted: 26 November 1997 相似文献
22.
Masumi Takano-Maruyama Yoshiro Ohara Kunihiko Asakura Takako Okuwa 《Journal of neuroinflammation》2006,3(1):19-8
Theiler's murine encephalomyelitis virus (TMEV) is divided into two subgroups on the basis of their different biological activities.
GDVII subgroup strains produce fatal poliomyelitis in mice without virus persistence or demyelination. In contrast, TO subgroup
strains induce demyelinating disease with virus persistence in the spinal cords of weanling mice. Two proteins, whose open
reading frames are located in the N-terminus of the polyprotein, recently have been reported to be important for TMEV biological
activities. One is leader (L) protein and is processed from the most N-terminus of the polyprotein; its function is still
unknown. Although the homology of capsid proteins between DA (a representative strain of TO subgroup) and GDVII strains is
over 94% at the amino acid level, that of L shows only 85%. Therefore, L is thought to be a key protein for the subgroup-specific
biological activities of TMEV. Various studies have demonstrated that L plays important roles in the escape of virus from
host immune defenses in the early stage of infection. The second protein is a 17–18 kDa protein, L*, which is synthesized
out-of-frame with the polyprotein. Only TO subgroup strains produce L* since GDVII subgroup strains have an ACG rather than
AUG at the initiation site and therefore do not synthesize L*. 'Loss and gain of function' experiments demonstrate that L*
is essential for virus growth in macrophages, a target cell for TMEV persistence. L* also has been demonstrated to be necessary
for TMEV persistence and demyelination. Further analysis of L and L* will help elucidate the pathomechanism(s) of TMEV-induced
demyelinating disease. 相似文献
23.
G protein modulation of voltage-sensitive muscarinic receptor signalling in mouse pancreatic acinar cells 总被引:2,自引:0,他引:2
Ong BH Ohsaga A Sato K Oshiro T Shirato K Maruyama Y 《Pflügers Archiv : European journal of physiology》2001,441(5):604-610
Submaximal stimulation of mouse pancreatic acinar cells by acetylcholine (ACh) generates periodic Ca2+ responses sensitive to the membrane potential. Monitoring the muscarinic Ca2+ responses using patch-clamp whole-cell current recordings, we examined the mechanism of guanine nucleotide-binding protein (G protein)-receptor interaction in terms of the membrane potential. The lowest ACh concentration able to elicit consistent repetitive spikes was 50 nM, in the presence of which hyperpolarization increased and depolarization decreased the spike frequency. The saturating concentration was 10 microM, this induced a sustained response insensitive to voltage. Internal guanosine 5'-tri- and diphosphates (GTP, GDP) depressed and potentiated the voltage sensitivity, respectively, but not for the response to a saturating ACh concentration (10 microM). Internal guanosine 5'-O-(3-thiotriphosphate) (GTPgammaS) abolished the voltage sensitivity. The results indicate that the ACh-induced Ca2+ response is sensitive to the membrane potential and that a close linkage exists between voltage sensitivity and the G protein association/dissociation cycle in the muscarinic receptor. 相似文献
24.
11q trisomy detected by fluorescence in situ hybridization 总被引:1,自引:0,他引:1
Takako Takano Yasuko Yamanouchi Shoko Kawashima Masatsune Date Shintaro Hashira Mitsushiro Kida Toshiaki Abe Yutaka Nakahori Yasuo Nakagome 《Clinical genetics》1993,44(6):324-328
Takano T, Yamanouchi Y, Kawashima S, Date M, Hashira S, Kida M, Abe T, Nakahori Y, Nakagome Y. 11q trisomy detected by fluorescence in situ hybridization. Clin Genet 1993: 44: 324–328. © Munksgaard, 1993 A patient with psychomotor developmental delay, multiple minor anomalies, congenital heart disease and left inguinal hernia is reported. His karyotype was 45,X/46,X,+mar (3 : 37 cells), and the marker chromosome was identified as t(Y;11) (q12;q14?) using fluorescence in situ hybridization and fluorescent chromosome painting. He was diagnosed as mosaic for de novo 11q trisomy. 相似文献
25.
Heat and water vapour transfer of protective clothing systems in a cold environment,measured with a newly developed sweating thermal manikin 总被引:1,自引:0,他引:1
Fukazawa T Lee G Matsuoka T Kano K Tochihara Y 《European journal of applied physiology》2004,92(6):645-648
A moveable sweating thermal manikin has recently been developed. Thermal and water-vapour resistances of three kinds of cold-protective clothing ensembles, laminated with polytetrafluoroethylene, polyurethane and without a laminate were measured, with the aid of the manikin in a cold environment of 5°C with a relative humidity of 70% and an air velocity of around 1.5 m s–1. Two sweating rates of 65 and 130 g m–2 h–1 were employed. Supplied heat fluxes in both of the sweat rates ranged from 350 W m–2 to 400 W m–2. To maintain a comfortable condition, the skin wettedness (w) (mean weighted value) had to be kept at 0.6. The measurements obtained from the manikin when testing the three ensembles were w=0.3 (approximately) for the low sweat rate and w0.6 for the high sweat rate, irrespective of the property differences among the ensembles. In addition, the condensation in the ensembles in comparison with those calculated from an analytical equation is discussed. Condensation mass fluxes in the ensembles obtained byexperiment and those from the calculation agreed sufficiently well. Thus, distribution of the condensation in the ensembles was estimated using the equation. 相似文献
26.
Spectral imaging fluorescence microscopy 总被引:2,自引:0,他引:2
Haraguchi T Shimi T Koujin T Hashiguchi N Hiraoka Y 《Genes to cells : devoted to molecular & cellular mechanisms》2002,7(9):881-887
The spectral resolution of fluorescence microscope images in living cells is achieved by using a confocal laser scanning microscope equipped with grating optics. This capability of temporal and spectral resolution is especially useful for detecting spectral changes of a fluorescent dye; for example, those associated with fluorescence resonance energy transfer (FRET). Using the spectral imaging fluorescence microscope system, it is also possible to resolve emitted signals from fluorescent dyes that have spectra largely overlapping with each other, such as fluorescein isothiocyanate (FITC) and green fluorescent protein (GFP). 相似文献
27.
Bibek Dutta Taichi Asami Tohru Imatomi Kento Igarashi Kento Nagata Tomomi Watanabe-Asaka Takako Yasuda Shoji Oda Manfred Shartl Hiroshi Mitani 《Journal of radiation research》2021,62(1):12
Transgenic expression in medaka of the Xiphophorus oncogene xmrk, under a pigment cell specific mitf promoter, induces hyperpigmentation and pigment cell tumors. In this study, we crossed the Hd-rR and HNI inbred strains because complete genome information is readily available for molecular and genetic analysis. We prepared an Hd-rR (p53+/−, p53−/−) and Hd-rR HNI hybrid (p53+/−) fish-based xmrk model system to study the progression of pigment cells from hyperpigmentation to malignant tumors on different genetic backgrounds. In all strains examined, most of the initial hyperpigmentation occurred in the posterior region. On the Hd-rR background, mitf:xmrk-induced tumorigenesis was less frequent in p53+/− fish than in p53−/− fish. The incidence of hyperpigmentation was more frequent in Hd-rR/HNI hybrids than in Hd-rR homozygotes; however, the frequency of malignant tumors was low, which suggested the presence of a tumor suppressor in HNI genetic background fish. The effects on tumorigenesis in xmrk-transgenic immature medaka of a single 1.3 Gy irradiation was assessed by quantifying tumor progression over 4 consecutive months. The results demonstrate that irradiation has a different level of suppressive effect on the frequency of hyperpigmentation in purebred Hd-rR compared with hybrids. 相似文献
28.
Okihiro Nishi Tsutomu Hara Takako Hara Yuji Sakka Fumihiko Hayashi Katsuhiko Nakamae Yoshibaru Yamada 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》1992,230(1):47-55
In this report we describe the surgical details involved in refilling the lenses of 13 rabbit and 3 primate eyes using an inflatable endocapsular balloon to restore accommodation. The procedure involves endocapsular phacoemulsification through a small buttonhole or dumbbell anterior capsulotomy or minicircular capsulotomy and the simultaneous preservation of capsular integrity, including the zonules and ciliary muscles. An inflatable balloon made of thin silicone membrane is then inserted into the empty capsular bag. A liquid silicone polymer is injected into the balloon through a delivery tube, and the empty capsular bag is refilled by the inflated balloon. The procedure was found to be reproducible, and an accommodation of 6 D was confirmed in one primate eye. Capsular opacification occurred, but the proliferation and migration of residual lens epithelial cells could be hindered by abundant refilling. This lens-refilling technique may provide restoration of accommodation in future cataract surgery.
Offprint requests to: O. Nishi 相似文献
29.
Naoki Matsushiro Takashi Sato Takako Iwaki Katsumi Doi Takeshi Kubo 《Nihon Jibiinkoka Gakkai kaiho》2003,106(3):211-219
Six cochlear implant recipients with hearing aids in the opposite ear were studied to survey binaural advantage. They were examined in separate tests by using a hearing aid alone, cochlear implant alone, and by using both devices (bimodal condition). Test items used were the Japanese monosyllable word list 67--S and Japanese HINT. Statistically significantly results were obtained in the bimodal condition, three out of six subjects were successful in the monosyllable word test and all successful in the Japanese HINT. We conclude that all subjects enjoyed binaural advantage in speech perception in bimodal condition with no conflict at the recognition level; even when different sounds from cochlear implant and contralateral hearing aid were received. The plasticity of the brain is thought to be of importance in the bimodal condition. 相似文献
30.