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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.
Lee JH 《Veterinary microbiology》2006,114(1-2):155-159
From 2001 to 2005, various specimens from cattle, pigs, and chickens were collected and examined for the presence of methicillin (oxacillin)-resistant Staphylococcus aureus (MRSA). The isolates from 19 specimens were tested for the presence of the mecA gene. Methicillin resistance was confirmed by determining the MICs for these isolates. Among these 19 mecA-positive isolates, 16 were consistently found to be resistant to methicillin. The mecR1 gene was found in all 19 mecA-positive S. aureus, and mecI was also detected in 15 of the mecA-positive S. aureus. The mecI gene had an identical sequence to the reference sequence in 9 of the 15 mecI-positive isolates. Three of the other six isolates had a C to T substitution at nucleotide 202, and one had a G to T substitution at nucleotide 43. These have been previously identified in MRSA from humans. Two isolates from chickens contained an addition of C at position 23. This mutation of MRSA has not been reported elsewhere. In all 15 mecI-positive MRSA, the sequence of the mec promoter/operator region was identical to the reference sequence. This suggests other mechanisms for overcoming the repression of resistance caused by mecI, beyond the simple product interaction between the mecA, mecRI, and mecI genes.  相似文献   
33.
Varietal seed mixtures tend to increase and stabilize crop yields, yet their application is sparse. Large-scale cultivation of variety mixtures may require a better understanding of how inter-varietal interactions and their interaction with the environment may influence the grain yield of variety mixtures relative to their component varieties. For this purpose, six variety mixtures of spring barley and 14 component varieties were grown in each of 17 trial environments. A total of 28 observed and a priori plant characteristics, including grain yield, disease severity and weed competitiveness, were derived for each component variety in each trial. The relationship between inter-varietal diversity of each characteristic and the mixing effect on grain yield was analysed. Additionally, various types of yield stability were estimated and compared among mixtures and component varieties. One mixture out-yielded all of its component varieties in almost half of the trial environments. Inter-varietal diversity in grain yield potential correlated significantly with mixing effect, as did straw length diversity when weighted with weed pressure. The grain yields of most mixtures were more stable across environments than their component varieties when accounting also for the general response to environmental productivity. Hence, most mixtures adapted slightly better to environmental productivity and were less sensitive to environmental stress than their component varieties. We conclude that the efficacy of variety mixtures may be enhanced by mixing relatively high-yielding varieties differing in responsiveness to environmental productivity.  相似文献   
34.
This study describes a method for discriminating Rangifer antlers from true Cervus antlers using agarose gel electrophoresis, capillary electrophoresis, quantitative real-time PCR, and allelic discrimination. Specific primers labeled with fluorescent tags were designed to amplify fragments from the mitochondrial D-loop genes for various Cervus subspecies and Rangifer tarandus differentially. A 466-bp fragment that was observed for both Cervus and Rangifer antlers served as a positive control, while a 270-bp fragment was specifically amplified only from Rangifer antlers. Allelic discrimination was used to differentiate between Cervus and Rangifer antlers, based on the amplification of specific alleles for both types of antlers. These PCR-based assays can be used for forensic and quantitative analyses of Cervus and Rangifer antlers in a single step, without having to obtain any sequence information. In addition, multiple PCR-based assays are more accurate and reproducible than a single assay for species-specific analysis and are especially useful in this study for the identification of original Cervus deer products from fraudulent Rangifer antlers.  相似文献   
35.
To evaluate potential of an auxotrophic Edwardsiella tarda mutant (Δalr Δasd E. tarda) as a delivery vehicle for DNA vaccine in fish, olive flounder (Paralichthys olivaceus) were immunized with the E. tarda mutant harboring plasmids (pG02-ASD-CMV-eGFP) for eukaryotic expression of the enhanced green fluorescent protein (eGFP) gene through either intraperitoneal (i.p.) or oral route, and the expression of eGFP in the internal organs and generation of antibody against eGFP in fish were analyzed. In fish i.p. injected with 2×10(7)CFU/fish of Δalr Δasd E. tarda harboring pG02-ASD-CMV-eGFP, expression of eGFP was detected in liver, kidney, and spleen from 1 day to 28 days post-injection. In fish orally administered with 1×10(9)CFU/fish of the bacteria, the eGFP band was detected in liver, kidney, and spleen from 1 day to 14 days post-administration, whereas, in intestine, the band was detected only at 1 day post-administration. Either oral or i.p. immunization of olive flounder with recombinant E. tarda that carried eGFP-expressing eukaryotic plasmids was successful to induce humoral adaptive immunity against not only E. tarda that was used as a delivery vehicle but also eGFP that was used as the reporter protein of DNA vaccine, suggesting attenuated E. tarda-vectored DNA vaccine has a potential to be used as a combined vaccine against infectious diseases in fish.  相似文献   
36.
Accumulating data suggest a relationship between chemerin and energy metabolism. Our group previously described gene cloning, expression analysis and the regulatory mechanism of chemerin and its own receptor in mice and cattle. The objective of the present study was to investigate the physiological effect of chemerin on endocrine changes and energy metabolism in sheep using a biologically stable chemerin analog. The chemerin analog was intravenously administrated (100 or 500 µg/head) to sheep, and plasma insulin and metabolites (glucose, nonesterified fatty acids (NEFA), triglyceride, total cholesterol and high‐density lipoprotein (HDL) cholesterol) were analyzed. The chemerin analog dramatically increased the insulin levels, and glucose levels were decreased. NEFA levels were slightly decreased at 20 min but then increased gradually from 60 to 180 min after analog administration. In addition, injection of the chemerin analog immediately increased triglyceride and total cholesterol but not HDL levels. These results suggested that chemerin analog regulated insulin secretion related to glucose metabolism and the release of triglycerides in sheep in vivo. This study provides new information about endocrine and metabolic changes in response to chemerin in sheep.  相似文献   
37.
The main objectives of this study were to investigate physicochemicals and antioxidant activities of new red rice (Oryza sativa cv. Gunganghongmi (GH)) by comparing normal brown (Nampyeongbyeo, NB) and reported red rice (Jukjinjubyeo, JB) in Korea. The nutritional constituents, including protein, oil, sugar, fatty acid, GABA, and γ-oryzanol were not significantly different between normal brown and colored rice. However, the ethanol extract of GH showed the highest phenolic content (24.7 ± 1.3 mg g?1). The ethanol extracts of GH showed higher scavenging activities against DPPH (0.2 mg mL?1 = 62.1 ± 2.5%) and ABTS (0.2 mg mL?1 = 63.2 ± 3.5%) radicals. Moreover, GH more inhibited LPS-induced nitric oxide (NO) production (13.2 ± 1.4 μM) than JB (18.3 ± 2.3 μM) and NB (22.1 ± 1.4 μM) at the same concentration (0.2 mg mL?1) without cytotoxicity. These results suggest that new red rice (GH) would be considered to be new functional rice due to its anti-oxidative effect and high nutrition.  相似文献   
38.
The use of regenerated silk fiber is limited due to its inferior mechanical properties in spite of high potential in a wide variety of applications. Many studies have been conducted in order to improve the mechanical properties of the regenerated silk materials, but no one has so far suggested an obvious solution. Meanwhile, some reports showed evidence that structural development of silk protein can be manipulated by physical interactions between silk fibroin (SF) and silk sericin (SS) during the regeneration process, especially in recrystallization process of SF. Such a hypothesis suggests a promising clue to enhance the mechanical properties of silk-based materials. Therefore, in this study, we tried to elucidate how SS can promote developing the molecular chain orientation of SF, resulting in an improvement of mechanical properties of regenerated silk fiber during spinning process. The tensile properties of the regenerated silk fiber were significantly improved compared to those of pure SF fiber when a proper amount of SS was blend with SF; both tenacity and breaking elongation increased by approximately 30 % and 70 % at three fold draw ratio, respectively. Quantitative analysis of X-ray diffraction and Herman’s orientation coefficient confirmed that such an improvement of tensile property was mainly caused by an increase of molecular orientation induced by sericin during the drawing process.  相似文献   
39.
Objective To determine the effect of 0.5% proparacaine in tonometry by evaluating corneal touch threshold (CTT) and intraocular pressure (IOP). Animal studied Nine rats (18 eyes, Sprague–Dawley) and 10 dogs (20 eyes, Beagle) Procedures The IOP and CTT were measured in each eye before and after topical anesthesia with 0.5% proparacaine. The IOP was evaluated using Tonopen for dogs and Tonolab for rats. The corneal sensitivity was evaluated by CTT through a Cochet–Bonnet aesthesiometer. Results The mean IOP was not significantly changed in rats or dogs before and after topical anesthesia. However, after application of proparacaine, CTT was significantly increased in both animal groups compared with that before application of proparacaine. Conclusion From this study, topical anesthesia was found to significantly lower the corneal sensitivity but have little effect on IOP measurements. In ophthalmologic examination, topical anesthesia can be used to reduce corneal sensation without an effect on IOP.  相似文献   
40.
This study was undertaken to identify and characterize amino acid substitutions in gyrA and parC related with quinolone resistance of 27 nalidixic acid-resistant (NaR) Salmonella isolates collected in poultry slaughterhouses in Korea. A total of 51 Salmonella isolates were detected from 44.8% (47/105) of the total samples from 15 poultry slaughterhouses examined, among which 27 (52.9%) NaR isolates were detected while ciprofloxacin (Cip) resistance was not present in the isolates. These 27 NaR isolates of DNA sequencing revealed that it contained three types of gyrA mutations in only D87 codon. Mutations in the D87 codon resulted in substitutions to G in most of the isolates, but D87Y and D87N exchanges were also detected. Although Cip resistance was absent, reduced susceptibility characterized by mutations in gyrA was apparent among Salmonella isolates from poultry slaughterhouses in Korea.  相似文献   
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