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1.
2.
Shigenori Inao Yoshiharu Takemitsu H. Edward Conrad 《Journal of orthopaedic science》1996,1(6):369-375
Monolayer cultures of 12-day chick embryo chondrocytes from the regions of dividing (zone 1), elongated (zone 2), and hypertrophied
(zone 3) chondrocytes in the tibial cpiphyseal growth plate were analyzed for their capacity to synthesize types II, IX, X,
and XI collagens. Synthesis of types II and IX collagens was markedly elevated in the zone 2 culture, while type X collagen
synthesis was maximal in zone 3. Type XI collagen was synthesized at low rates in all cultures, with some elevation of its
rate in zones 2 and 3. In terms of mol percent of total collagen synthesis, types II and IX collagens decreased from zone
1 to zone 3, while type X collagen increased progressively. Thus, the composition of the extracellular collagens produced
by the different zones changed markedly during chondrocyte differentiation. In addition, type X collagen was released exclusively
into the culture medium, whereas type XI collagen was retained in the extracellular cell-associated matrix. In contrast, types
II and IX collagens were found in both the culture medium and the cell matrix pools. Although types II and IX collagens showed
similar changes during differentiation, the synthetic molar ratios of these two collagens varied from 3 to 18 in different
cultures, suggesting that the synthesis of these two products is not tightly coupled in these cells. 相似文献
3.
4.
Yoko Kamitani Eiji Kajii Toshio Suda Shigenori Ikemoto 《Journal of human genetics》1992,37(4):271-283
Summary In order to examine expression of the Tn antigen on erythroid cells from a patient with Tn syndrome, we applied a selective two phase liquid culture system for human erythroid progenitors in peripheral blood. The cells were analyzed with flow cytometry employing an anti-Tn antibody and a lectin ofVicia villosa which recognizes only the Tn determinant. In the second phase, the Tn antigen was expressed on the cultured cells from the patient on day 3 and Tn-positive cells reached 62.7% on day 9. On the other hand, Tn-positive cells were not detected in the volunteer's cultured cells. When the patient's cells were co-cultured with the cells from a healthy voluteer, the percentage of Tn-positive cells was much lower than the expected value, suggesting that the normal cells suppressed the expression of Tn antigen on the patient's cells. 相似文献
5.
Analysis of mRNA with microsomal fractionation using a SAGE-based DNA microarray system facilitates identification of the genes encoding secretory proteins 总被引:1,自引:0,他引:1
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Toyoda N Nagai S Terashima Y Motomura K Haino M Hashimoto S Takizawa H Matsushima K 《Genome research》2003,13(7):1728-1736
In the regulation of host defense responses such as inflammation and immunity, the secretory proteins, including membrane proteins, play central roles. Although many secretory proteins have been identified by using methods such as differential display, random screening, or the signal sequence trap method, each method suffers from poor reproducibility, low sensitivity, or time-consuming or laborious work. Therefore, the strategy for facilitating the selection of the genes encoding the secretory proteins is desired. In this paper, we describe a system for isolating the genes encoding secretory proteins by analyzing mRNAs with microsomal fractionation on serial analysis of gene expression (SAGE)-based DNA microarray system. This system succeeded in discriminating the genes encoding secretory proteins from ones encoding nonsecretory proteins with 80% accuracy. We applied this system to human T lymphocytes. As a result, we were able to identify the genes that are not only encoding secretory proteins but also expressing selectively in a specific subset of T lymphocytes. The SAGE-based DNA microarray system is a promising system to identify the genes encoding specific secretory proteins. 相似文献
6.
Yukiko Nishikawa Shigenobu Shibata Takao Shimazoe Shigenori Watanabe 《Neuroscience letters》1996,220(3):217
Optic nerve stimulation has been reported to evoke a field potential (FP) in rat suprachiasmatic nucleus (SCN) slices. Methylcobalamin,δ-(5,6-dymethylbenzimidazoyl)-Co-methyl-cobamide (Me-B12) enhanced this FP and the enhancement lasted more than 1 h after washing out. Maximal enhancement (143.6±9.8%) was achieved at a concentration of 10 μM. By contrast, cyanocobalamin containing CN- instead of CH3-showed no enhancement of the amplitude in the FP. Me-B12 induced enhancement of FP was strongly blocked by an N-methyl-
-aspartate (NMDA) receptor antagonist,
-2-amino-5-phosphonovaleric acid (APV). These results indicate that CH3- in the Me-B12 is required to modulate the FP amplitude and the NMDA receptor is involved in the long-lasting FP enhancement induced by Me-B12. The present results suggest that Me-B12 modifies the photic entrainment of the circadian clock in the suprachiasmatic nucleus via an activation of NMDA receptors. 相似文献
7.
Moriguchi S Watanabe S Kita H Nakanishi H 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2002,144(2):238-246
It has been suggested that behavioral methamphetamine sensitization involves changes in cortical excitatory synaptic inputs to neostriatal (Str) projection neurons. To test this, we performed blind whole-cell recording of medium spiny neurons in Str slice preparations. In Str neurons of naive rats, the amplitude of the subcortical white matter stimulation-induced N-methyl- D-aspartate receptor-mediated excitatory postsynaptic potentials (NMDA-EPSPs) was decreased upon hyperpolarization, owing to the voltage-dependent Mg(2+) blockade of NMDA receptor channels. In contrast, the amplitude of the NMDA-EPSPs in Str neurons of rats undergoing methamphetamine withdrawal (MW) did not show the Mg(2+) blockade and was nearly voltage independent over the membrane potential range of -70 to -110 mV. Application of the specific protein kinase C (PKC) activator, phorbol 12, 13- DL-acetate, blocked the voltage-dependent Mg(2+) blockade of NMDA receptor channels in Str neurons of naive rats. Application of the specific activator of cAMP-dependent protein kinase A (PKA), Sp-cAMPS-triethylamine salt, increased the amplitude of the NMDA receptor-mediated EPSPs at the rest but not at hyperpolarized potentials. Coapplication of the PKC and PKA activators yielded NMDA-EPSPs similar to those seen in Str neurons of MW rats. In Str slices of naive rats, tetanic subcortical white matter stimulation induced long-term depression of field potentials. In Str slices treated with the PKC and/or PKA, the same stimulation induced long-term potentiation of field potentials similar to those observed in slices obtained from MW rats. These results suggest that the enhancement of the NMDA receptor-mediated corticostriatal synaptic transmission plays an important role in behavioral methamphetamine sensitization. This enhancement is probably associated with phosphorylation of NMDA receptors mediated by the simultaneous activation of PKC and PKA. 相似文献
8.
Notch signaling regulates left-right asymmetry determination by inducing Nodal expression 总被引:1,自引:0,他引:1
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9.
Aoi W Naito Y Sakuma K Kuchide M Tokuda H Maoka T Toyokuni S Oka S Yasuhara M Yoshikawa T 《Antioxidants & redox signaling》2003,5(1):139-144
Dietary antioxidants may attenuate oxidative damage from strenuous exercise in various tissues. Beneficial effects of the antioxidant astaxanthin have been demonstrated in vitro, but not yet in vivo. We investigated the effect of dietary supplementation with astaxanthin on oxidative damage induced by strenuous exercise in mouse gastrocnemius and heart. C57BL/6 mice (7 weeks old) were divided into groups: rested control, intense exercise, and exercise with astaxanthin supplementation. After 3 weeks of exercise acclimation, both exercise groups ran on a treadmill at 28 m/min until exhaustion. Exercise-increased 4-hydroxy-2-nonenal-modified protein and 8-hydroxy-2'-deoxyguanosine in gastrocnemius and heart were blunted in the astaxanthin group. Increases in plasma creatine kinase activity, and in myeloperoxidase activity in gastrocnemius and heart, also were lessened by astaxanthin. Astaxanthin showed accumulation in gastrocnemius and heart from the 3 week supplementation. Astaxanthin can attenuate exercise-induced damage in mouse skeletal muscle and heart, including an associated neutrophil infiltration that induces further damage. 相似文献
10.
Yasushi Kondoh Matsutaro Murakami Weimin Yin Shigenori Mizusawa Hiroyuki Nakamichi Ken Nagata 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1994,99(3):375-382
The distribution of functionally active monoamine oxidase type A (MAO-A) was investigated by in vivo quantitative autoradiography using [14C]clorgyline in normal, conscious rat brain. [14C]clorgyline was synthesized by the methylation reaction of N-desmethylclorgyline using [14C]methyliodide. Sixty minutes after [14C]clorgyline administration (1.58 MBq/animal i.v.), the brains were removed and prepared for autoradiography by washing the brain sections with 5% trichloroacetic acid solution to remove the nonbinding free tracer. The amount of MAO-A was calculated from the regional acid-insoluble tissue radioactivity and the specific activity of the tracer. The highest amount of MAO-A (5.84 nmol/g tissue) was found in the locus coeruleus. The interpeduncular nucleus, habenular nucleus, fasciculus retroflexus, and solitary tract nucleus possessed over 1.6 nmol/g tissue of MAO-A. Among 23 regions of interest, the lowest amount of MAO-A (0.37 nmol/g tissue) was found in the globus pallidus. The findings of this study suggest that the pattern of MAO-A parallels both in neuroanatomical distribution and in density that of norepinephrine and serotonin innervation. The MAO-A concentration was, however, relatively low in the dopamine-related areas. This corresponded to the previous results obtained by histochemical analysis. In addition, among the white matter structures, a high amount of MAO-A was found specifically in the fasciculus retroflexus. 相似文献