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31.
Expression of osteopontin (OPN) was investigated in the spinal cords of rats with clip compression injury. Western blot analysis demonstrated that OPN protein increased significantly in the spinal cord during the early stages after injury. The increased expression of OPN was partially paralleled by that of proliferating cell nuclear antigen (PCNA). Immunohistochemical staining showed that OPN was expressed in proliferating activated microglia/macrophages in core lesions and in some astrocytes at the periphery of lesions. These results indicate that expression of OPN protein increases mainly in activated microglia/macrophages after spinal cord injury, suggesting that OPN is related to cell proliferation during the early stages after injury, probably leading to tissue remodeling.  相似文献   
32.
The effect of the Maillard reaction on the allergenicity of squid tropomyosin (TM) was investigated. When TM was reacted with ribose (TM-ribose), its human-specific IgE-binding ability decreased markedly and alpha-chymotryptic digestibility of TM was also altered at the early stage of the Maillard reaction. On the other hand, the modification of the lysine residues in TM using 2,4,6-trinitrobenzenesulfonic acid had no effect on the allergenicity and alpha-chymotryptic digestibility of TM. Therefore, the structural change in TM induced by the Maillard reaction would cause the reduction of the allergenicity, rather than the block of lysine residues. Although peptic digestion diminished the specific IgE-binding ability of TM, the reduction of the allergenicity by the Maillard reaction remained after peptic digestion. These results suggest that hypersensitive reaction of TM-ribose in the human body might be lower than that of native TM.  相似文献   
33.
The expression of protein kinase C (PKC) was studied in the bovine retina by immunohistochemical analysis. Western blot analysis showed that PKC isoforms, including alpha, betaI, delta and theta, were detected in the bovine retina. By immunohistochemistry, both PKC alpha and betaI were expressed in all retinal layers, with an intense localization of both PKC alpha and betaI detected in bipolar cells in the inner nuclear cell layer and in some glial cells in ganglion cell layers. The immunoreactivity of both PKC delta and theta was quite weak in the retinal layers, compared with that of PKC alpha and betaI. These findings suggest that both conventional and novel PKCs are differentially expressed in the bovine retina.  相似文献   
34.
The expression pattern of CD44 was studied in the rat testis following ischemia/reperfusion (I/R) injury to elucidate the possible role of the CD44 adhesion molecule in acute experimental testicular torsion. Western blot analysis showed that CD44 expression began to increase significantly 24 hr after reperfusion, compared with the normal control; the increased expression persisted until 96 hr after I/R. Immunohistochemistry showed that, in the normal testis, CD44 was constitutively expressed mainly in ED2-positive resident macrophages in the interstitial space. After I/R, the majority of inflammatory cells in the interstitial space surrounding the damaged tubules were ED1-positive macrophages that were CD44-positive. These findings suggest that the significant increase in CD44 expression that occurs during the delayed phase after reperfusion originates from infiltrating macrophages possibly in anticipation of the migration and adhesion of additional macrophages into the affected testis.  相似文献   
35.
We developed a simple approach to combine broad classes of dissimilar materials into heterogeneously integrated electronic systems with two- or three-dimensional layouts. The process begins with the synthesis of different semiconductor nanomaterials, such as single-walled carbon nanotubes and single-crystal micro- and nanoscale wires and ribbons of gallium nitride, silicon, and gallium arsenide on separate substrates. Repeated application of an additive, transfer printing process that uses soft stamps with these substrates as donors, followed by device and interconnect formation, yields high-performance heterogeneously integrated electronics that incorporate any combination of semiconductor nanomaterials on rigid or flexible device substrates. This versatile methodology can produce a wide range of unusual electronic systems that would be impossible to achieve with other techniques.  相似文献   
36.
Quercetin 3-O-β-(2"-galloyl)-rhamnopyranoside (QGR) is a naturally occurring quercitrin gallate, which is a polyphenolic compound that was originally isolated from Persicaria lapathifolia (Polygonaceae). QGR has been shown to have an inhibitory effect on nitric oxide (NO) production in lipopolysaccharide (LPS)-stimulated macrophage RAW 264.7 cells. Therefore, this study was conducted to investigate the inhibitory effect of QGR on nitric oxide production and inducible nitric oxide synthases (iNOS) expression in LPS-stimulated Balb/c mice. To accomplish this, 10 mg/kg of QGR was administered via gavage once a day for 3 days. iNOS was then induced by intraperitoneal injection of LPS. Six hours after the LPS treatment the animals were sacrificed under ether anethesia. The serum levels of NO were then measured to determine if QGR exerted an inhibitory effect on NO production in vivo. LPS induced an approximately 6 fold increase in the expression of NO. However, oral administration of QGR reduced the LPS induced increase in NO by half. Furthermore, RT-PCR and western blot analysis revealed that the increased levels of iNOS expression that occurred in response to treatment with LPS were significantly attenuated in response to QGR pretreatment. Histologically, LPS induced the infiltration of polymorphonuclear neutrophils in portal veins and sinusoids and caused the formation of a large number of necrotic cells; however, pretreatment with QGR attenuated these LPS induced effects. Taken together, these results indicate that QGR inhibits iNOS expression in vivo as well as in vitro and has antiinflammatory potentials.  相似文献   
37.
Kim SI  Na YE  Yi JH  Kim BS  Ahn YJ 《Veterinary parasitology》2007,145(3-4):377-382
The acaricidal activity of methanolic extracts from 40 oriental medicinal plant species and a steam distillate of Cinnamomum camphora towards poultry house-collected adult Dermanyssus gallinae De Geer was examined using direct contact and vapour phase toxicity bioassays. Results were compared with those of 15 acaricides currently used. In filter paper contact toxicity bioassays using adult D. gallinae, C. camphora steam distillate (0.0051 mgcm(-2)) was the most toxic material, followed by extracts from Asarum sieboldii var. seoulens whole plant, Eugenia caryophyllata flower bud and Mentha arvensis var. piperascens whole plant (0.0063-0.0072 mgcm(-2)), based upon 24h LD(50) values. The acaricidal activity of these four plant preparations was almost comparable to that of profenofos (LD(50), 0.003 mgcm(-2)) but less effective than dichlorvos (LD(50), 0.0004 mgcm(-2)). The toxicity of Illicium verum fruit and Lysimachia davurica leaf extracts (0.09 mgcm(-2)) was almost comparable to that of benfuracarb, prothiofos, propoxur and fenthion (0.053-0.070mgcm(-2)). In vapour phase toxicity tests, these plant preparations were more effective in closed containers than in open ones, indicating that the mode of delivery of these plant extracts was largely a result of action in the vapour phase. Plants described herein merit further study as potential D. gallinae control agents.  相似文献   
38.
The growth-inhibiting activity of Coptis japonica (Makino) root-derived materials toward eight human intestinal bacteria was examined using an impregnated paper disk method and compared to that of four commercially available isoquinoline alkaloids [berberine sulfate (BS), berberine iodide (BI), palmatine chloride (PC), and palmatine sulfate(PS)], as well as that of Thea sinensis leaf-derived epigallocatechin gallate (EGCG). The biologically active constituents of the Coptis extract were characterized as the isoquinoline alkaloids berberine chloride (BC), palmatine iodide (PI), and coptisine chloride (CC) by spectral analysis. The growth responses varied with both chemical and bacterial strain used. In a test using 500 microg/disk, BC and PI produced a clear inhibitory effect against Bifidobacterium longum, Bifidobacterium bifidum, Clostridium perfringens, and Clostridium paraputrificum, whereas weak or no inhibition was observed in Bifidobacterium adolescentis, Lactobacillus acidophilus, Lactobacillus casei, and Escherichia coli. At 1000 microg/ disk, CC revealed weak or no growth inhibition toward all test bacteria, whereas EGCG exhibited weak growth inhibition against only C. perfringens and C. paraputrificum. Among various isoquinoline alkaloids, BC exhibited more potent inhibitory activity toward C. perfringens than BI and BS, whereas the inhibitory effect was more pronounced in PI compared to PC and PS. The Coptis root-derived materials did not promote growth of B. longum and C. perfringens.  相似文献   
39.
The larvicidal component from sawdust of Thujopsis dolabrata var. hondai (Family Cupressaceae) against the pine needle gall midge (Thecodiplosis japonensis) was isolated by chromatographic techniques and characterized by spectral analysis as carvacrol. In a laboratory study using the impregnated filter paper method, carvacrol was more toxic to T. japonensis larvae than β-thujaplicine, cedrol, α-terpinol, thujone or thymol. In field studies with soil injections of carvacrol, this compound exhibited potent larvicidal activity, suggesting that this activity might be attributable to fumigant action. In a test with trunk implantation, a mixture of carvacrol and phosphamidon (0·15+0·15 ml cm-1 diameter at breast height) revealed much more potent larvicidal activity than phosphamidon alone (0·3 ml cm-1 DBH) in spite of little or no larvicidal activity of carvacrol alone (0·3 ml cm-1 DBH), indicating a possible synergistic effect. As a naturally occurring insecticide, carvacrol could be useful as a new preventive agent against damage caused by T. japonensis. © 1997 SCI.  相似文献   
40.
Vibrio anguillarum is a major pathogenic bacterium that causes vibriosis and septicemia in fish and shellfish. In this study, we identified the groESL genes, which encode bacterial chaperonins, from V. anguillarum. The groE gene cluster consisted of a 291-bp groES gene, a 69-bp intergenic spacer region, and a 1,635-bp groEL gene order. Sequence analysis with the groESL gene of Vibrio species exhibited that the groEL gene was more species-specific and suitable than the groES gene for V. anguillarum detection. Owing to the difficulty in distinguishing V. anguillarum from the closely related V. ordalii, we compared the sequences of groEL from V. anguillarum and the groEL homolog hsp60 from V. ordalii, in order to design a primer set based on a region dissimilar between the two. PCR with the groEL primer set produced a clear 195-bp amplicon in six serotypes of V. anguillarum, whereas 23 Vibrio species of 39 samples, including V. ordalii, and 10 species of enteric bacteria gave no bands. PCR using the groEL primers also amplified a unique product from V. anguillarum-infected flounder and oyster tissues. These results demonstrate that the groEL-target PCR assay is a sensitive and species-specific tool for the detection of V. anguillarum infection.  相似文献   
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