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131.
Characterization of the cells in the repair tissue of full-thickness articular cartilage defects 总被引:1,自引:0,他引:1
H. Nakajima Tatsuhiko Goto Osamu Horikawa Toshiyuki Kikuchi Masayuki Shinmei 《Histochemistry and cell biology》1998,109(4):331-338
It is well established that a full-thickness articular cartilage defect is repaired with a fibrocartilaginous tissue, cells
of which are derived from undifferentiated mesenchymal stem cells in the bone marrow. To characterize the repair cells biochemically,
full-thickness defects were created in rabbit knee joints and the repair tissues taken at 3, 6, and 12 weeks after surgery.
The repair cells were cultured and examined biochemically to investigate the effects of four exogenous growth factors with
regard to the metabolism of type II collagen and proteoglycans. A significant increase of carboxy-terminal type II procollagen
peptide production was observed in the conditional medium of the repair cells, especially taken at 6 weeks after surgery,
in the presence of each growth factor. Glycosaminoglycan content was also increased and proteoglycan synthesis stimulated.
The repair cells taken at the early stage of the repair process could originally have more activity of type II collagen synthesis,
and the growth factors used could enhance the differentiation of the repair cells in vitro.
Accepted: 3 November 1997 相似文献
132.
Yuzuru Hamada Bambang Suryobroto Shunji Goto Suchinda Malaivijitnond 《International journal of primatology》2008,29(5):1271-1294
Long-tailed macaques (Macaca fascicularis fascicularis) are widely distributed in Southeast Asia and are morphologically and genetically (Tosi et al. in International Journal of Primatology 23:161–178, 2002) distinguishable on either side of the Isthmus of Kra (ca. 10.5°N). We compared the somatometry and body color of 15 local populations of long-tailed macaques in Thailand distributed
over areas from 6.5°N to 16.3°N and also a Thai rhesus macaque population at 17.2°N. Limb proportions and body color variation
follow the geographical trend. However, contrary to a previous report, body size does not decrease with latitude in the northern
group and also in the southern (southerly distributed) rhesus macaque. Relative tail length (RTL) and color contrast in yellow
between the back and thigh are the sole traits that distinctively separate the 2 groups: the southern group has a long relative
tail length (RTL >125%) and small color contrast, whereas the northern group has a short RTL (<120%) and large color contrast.
The southern rhesus macaques appear to have somatometric and body color traits that follow the geographical trend in long-tailed
macaques, though they maintain their distinctive species-specific traits of shorter RTL (ca. 55%), shorter relative facial length, and a bipartite body color pattern. Researchers assume that the northern group of long-tailed
macaques and the southern rhesus macaques had undergone partial introgression with each other. Montane refugia present during
the glacial period are localities in which introgression occurred in long-tailed macaques. 相似文献
133.
Ishida-Fujii K Goto S Kuboki H Hirano S Sakamoto M Sato M 《BioFactors (Oxford, England)》2004,21(1-4):155-158
Lactic acid bacteria were isolated from an alcohol fermentation broth, and the activity as a probiotic was examined using pathogenic E. coli. Thirty-six strains exhibiting good growth were isolated in the medium of concentrated mush which was a residue resulted in the alcohol distillation process. One of these strains, Lactobacillus paracasei subsp. paracasei I-5, could be grown in the medium containing 8 vol% ethanol and at 45 degrees C. The characteristics were different from the type strain, L. paracasei subsp. paracasei NBRC 15889. L. paracasei I-5 showed an excellent growth in the concentrated mush, which just diluted two-fold and adjusted the pH. ICR mice were fed with a standard germ-free feed (CMF) and the strain I-5 (7 x 10(9) cells/day) was orally administrated for 11 days prior to the intraperitoneal challenge with pathogenic E. coli Juhl. After the challenge, mice administrated the strain I-5 exhibited a high survival rate and survival extension days (p < 0.01) compared with the control. The results suggested that the strain might enhance the animal resistance against microbial pathogens. Neonatal diarrhea caused by E. coli is a serious disease in calf breeding. The strain might be practically valuable to prevent diarrhea in calves. 相似文献
134.
Manabu Kume Yuki Terashima Toshihiro Wada Yoh Yamashita 《Zeitschrift fur angewandte Ichthyologie》2019,35(4):876-883
Although the Japanese eel Anguilla japonica is a commercially important species, its habitat use is not well understood during its life stages in the river. In this study, we investigated the longitudinal distribution and microhabitat use of young Japanese eels (<200 mm in total length [TL], which correspond to elver and early yellow stages) using 180 quadrates (1 m × 1 m) in six stations in a small river (approximately 11.5 km long, 3.0–25.0 m wide) that flows through paddy areas in Fukushima Prefecture, Japan. No differences were observed in the TL of eels among the sampling stations. The analysis using generalized linear models showed that eel density increased as number of weirs decreased. The analysis using generalized additive models showed that water depth, current velocity, and substrate complexity were important factors determining microhabitat use. Eels used shallow habitats (<35 cm) with slow currents (5–40 cm/s) and high complex riverbeds (>0.35 in index of substrate complexity). These findings provide useful information to conserve and manage wild eels inhabiting small rivers flowing through paddy areas. 相似文献
135.
Sato H Kato R Isogai Y Saka G Ohtsuki M Taketomi Y Yamamoto K Tsutsumi K Yamada J Masuda S Ishikawa Y Ishii T Kobayashi T Ikeda K Taguchi R Hatakeyama S Hara S Kudo I Itabe H Murakami M 《The Journal of biological chemistry》2008,283(48):33483-33497
Among the many mammalian secreted phospholipase A2 (sPLA2) enzymes, PLA2G3 (group III secreted phospholipase A2) is unique in that it possesses unusual N- and C-terminal domains and in that its central sPLA2 domain is homologous to bee venom PLA2 rather than to other mammalian sPLA2s. To elucidate the in vivo actions of this atypical sPLA2, we generated transgenic (Tg) mice overexpressing human PLA2G3. Despite marked increases in PLA2 activity and mature 18-kDa PLA2G3 protein in the circulation and tissues, PLA2G3 Tg mice displayed no apparent abnormality up to 9 months of age. However, alterations in plasma lipoproteins were observed in PLA2G3 Tg mice compared with control mice. In vitro incubation of low density (LDL) and high density (HDL) lipoproteins with several sPLA2s showed that phosphatidylcholine was efficiently converted to lysophosphatidylcholine by PLA2G3 as well as by PLA2G5 and PLA2G10, to a lesser extent by PLA2G2F, and only minimally by PLA2G2A and PLA2G2E. PLA2G3-modified LDL, like PLA2G5- or PLA2G10-treated LDL, facilitated the formation of foam cells from macrophages ex vivo. Accumulation of PLA2G3 was detected in the atherosclerotic lesions of humans and apoE-deficient mice. Furthermore, following an atherogenic diet, aortic atherosclerotic lesions were more severe in PLA2G3 Tg mice than in control mice on the apoE-null background, in combination with elevated plasma lysophosphatidylcholine and thromboxane A2 levels. These results collectively suggest a potential functional link between PLA2G3 and atherosclerosis, as has recently been proposed for PLA2G5 and PLA2G10. 相似文献
136.
137.
The programmed cell death 4 (Pdcd4), a translation inhibitor, plays an essential role in tumor suppression, but its role in apoptosis remains unclear. Here we show that Pdcd4 is a critical suppressor of apoptosis by inhibiting the translation of procaspase-3 mRNA. Pdcd4 protein decreased more rapidly through microRNA-mediated translational repression following apoptotic stimuli than did the activation of procaspase-3, cleavage of poly(ADP)ribose polymerase (PARP) by active caspase-3, and nuclear fragmentation. Strikingly, the loss of Pdcd4 by the specific RNA interference increased procaspase-3 expression, leading to its activation and PARP cleavage even without apoptotic stimuli, and sensitized the cells to apoptosis. Thus, our findings provide insight into a novel mechanism for Pdcd4 as a regulator of apoptosis. 相似文献
138.
Hirokazu Kariyazono Ryo Nadai Rin Miyajima Yuki Takechi‐Haraya Teruhiko Baba Akira Shigenaga Keiichiro Okuhira Akira Otaka Hiroyuki Saito 《Journal of peptide science》2016,22(2):116-122
Nanodiscs are composed of scaffold protein or peptide such as apolipoprotein A‐I (apoA‐I) and phospholipids. Although peptide‐based nanodiscs have an advantage to modulate the size of nanodiscs by changing phospholipid/peptide ratios, they are usually less stable than apoA‐I‐based nanodiscs. In this study, we designed a novel nanodisc scaffold peptide (NSP) that has proline‐punctuated bihelical amphipathic structure based on apoA‐I mimetic peptides. NSP formed α‐helical structure on 1‐palmitoyl‐2‐oleoyl phosphatidylcholine (POPC) nanodiscs prepared by cholate dialysis method. Dynamic light scattering measurements demonstrated that diameters of NSP nanodiscs vary depending upon POPC/NSP ratios. Comparison of thermal unfolding of nanodiscs monitored by circular dichroism measurements demonstrated that NSP forms much more stable nanodiscs with POPC than monohelical peptide, 4F, exhibiting comparable stability to apoA‐I‐POPC nanodiscs. Intrinsic Trp fluorescence measurements showed that Trp residues of NSP exhibit more hydrophobic environment than that of 4 F on nanodiscs, suggesting the stronger interaction of NSP with phospholipids. Thus, the bihelical structure of NSP appears to increase the stability of nanodiscs because of the enhanced interaction of peptides with phospholipids. In addition, NSP as well as 4F spontaneously solubilized POPC vesicles into nanodiscs without using detergent. These results indicate that bihelical NSP forms nanodiscs with comparable stability to apoA‐I and has an ability to control the size of nanodiscs simply by changing phospholipid/peptide ratios. Copyright © 2016 European Peptide Society and John Wiley & Sons, Ltd. 相似文献
139.
Terahara K Nochi T Yoshida M Takahashi Y Goto Y Hatai H Kurokawa S Jang MH Kweon MN Domino SE Hiroi T Yuki Y Tsunetsugu-Yokota Y Kobayashi K Kiyono H 《Biochemical and biophysical research communications》2011,(3):822-828
The intestinal epithelium contains columnar epithelial cells (ECs) and M cells, and fucosylation of the apical surface of ECs and M cells is involved in distinguishing the two populations and in their response to commensal flora and environmental stress. Here, we show that fucosylated ECs (F-ECs) were induced in the mouse small intestine by the pro-inflammatory agents dextran sodium sulfate and indomethacin, in addition to an enteropathogen derived cholera toxin. Although F-ECs showed specificity for the M cell-markers, lectin Ulex europaeus agglutinin-1 and our monoclonal antibody NKM 16-2-4, these cells also retained EC-phenotypes including an affinity for the EC-marker lectin wheat germ agglutinin. Interestingly, fucosylation of Peyer’s patch M cells and F-ECs was distinctly regulated by α(1,2)fucosyltransferase Fut1 and Fut2, respectively. These results indicate that Fut2-mediated F-ECs share M cell-related fucosylated molecules but maintain distinctive EC characteristics, Fut1 is, therefore, a reliable marker for M cells. 相似文献
140.
Gomes CM Goto H Magnanelli AC Monteiro HP Soares RP Corbett CE Gidlund M 《Experimental parasitology》2001,99(4):190-197
Insulin-like growth factor (IGF)-I constitutively present in the skin is one of the first growth factors that Leishmania parasites encounter after transmission to the vertebrate host. We have previously shown that IGF-I is a potent growth-promoting factor for Leishmania parasites. IGF-I binds specifically to a single-site putative receptor at the parasite membrane, triggering a cascade of phosphorylation reactions. In the present article we characterize the receptor for IGF-I on Leishmania (Leishmania) mexicana promastigotes. The receptor is a monomeric glycoprotein with a molecular mass of 65 kDa and is antigenically related to the alpha chain of human type 1 IGF-I receptor. Upon IGF-I stimulation the receptor undergoes autophosphorylation on tyrosine residues with activation of its signaling pathway. Activation of the IGF-I receptor also leads to phosphorylation of an 185-kDa molecule that is homologous to the substrate of the insulin receptor present in human cells, the insulin receptor substrate 1 (IRS-1). 相似文献