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111.
Atopic dermatitis (AD) is a chronic inflammatory skin disease in which skin barrier dysfunction leads to dryness, pruritus, and erythematous lesions. AD is triggered by immune imbalance and oxidative stress. Echinochrome A (Ech A), a natural pigment isolated from sea urchins, exerts antioxidant and beneficial effects in various inflammatory disease models. In the present study, we tested whether Ech A treatment alleviated AD-like skin lesions. We examined the anti-inflammatory effect of Ech A on 2,4-dinitrochlorobenzene (DNCB)-induced AD-like lesions in an NC/Nga mouse model. AD-like skin symptoms were induced by treatment with 1% DNCB for 1 week and 0.4% DNCB for 5 weeks in NC/Nga mice. The results showed that Ech A alleviated AD clinical symptoms, such as edema, erythema, and dryness. Treatment with Ech A induced the recovery of epidermis skin lesions as observed histologically. Tewameter® and Corneometer® measurements indicated that Ech A treatment reduced transepidermal water loss and improved stratum corneum hydration, respectively. Ech A treatment also inhibited inflammatory-response-induced mast cell infiltration in AD-like skin lesions and suppressed the expression of proinflammatory cytokines, such as interferon-γ, interleukin-4, and interleukin-13. Collectively, these results suggest that Ech A may be beneficial for treating AD owing to its anti-inflammatory effects.  相似文献   
112.
Model reactions with various -SH, -OH and -NH nucleophiles in an aprotic solvent were used to characterise the nature of the enzymatic conversion of thiadiazolidines to triazolidines. This conversion results in greater inhibition of protoporphrinogen oxidase (protox). It is inferred that GST-isoforms probably promote formation of one of the intermediates.  相似文献   
113.
Transcatheter arterial embolization (TAE) and transcatheter arterial chemoembolization (TACE) are standard treatments for advanced hepatocellular carcinoma (HCC) and particularly for unresectable tumors or liver metastases in humans. However, reports on TACE used in veterinary medicine are few. This study aimed to evaluate the feasibility and safety of drug-eluting bead transarterial chemoembolization (DEB-TACE). We performed DEB-TACE in four clinically normal dogs and pharmacokinetically compared the results against hepatic arterial infusion (HAI) of cisplatin in two dogs. Drug-eluting beads (DEB) loaded with cisplatin were injected through a microcatheter for selective embolization of the left hepatic artery. After embolization, computed tomography (CT) images and histological examination findings were obtained during a 4-week observation period. Serum platinum concentrations were measured to evaluate cisplatin after each procedure. Biochemical analysis was performed during a 12-week observation period. Embolization was successful in all dogs, and there were no clinically apparent abnormalities. Embolization was confirmed up to 4 weeks after DEB-TACE in two of the four dogs and up to 1 week in the other two dogs using postoperative CT images. Cisplatin was not detected in peripheral veins in all dogs after DEB-TACE, but it was detected in trace amounts after HAI. DEB-TACE using cisplatin was safe and well tolerated by normal dogs. DEB-TACE may be useful in terms of determining systemic toxicity and drug concentration within tumors.  相似文献   
114.
Substitution lines with reciprocal substitutions of chromosomes containing recessive alleles of the homoeologous group 5 chromosomeVrn genes between varieties of winter wheat with high vernalisation requirement (‘Mironovskaya 808’) and low vernalisation requirements (‘Bezostaya 1’) have been created. On this basis the genetic determination of vernalisation requirement was established. Substitution lines Mironovskaya 808 (Bezostaya 1 5A), Mironovskaya 808 (Bezostaya 1 5B), Mironovskaya 808 (Bezostaya 1 5D) and reciprocal substitution lines Bezostaya 1 (Mironovskaya 808 5A), Bezostaya 1 (Mironovskaya 808 5B) and Bezostaya 1 (Mironovskaya 808 5D) were grown under different durations of vernalisation (3, 4, 5, 6, 7 and 8 weeks) and their response was evaluated. Photoperiodic sensitivity of the original parental genotypes was also determined. Reciprocal substitution lines of the same chromosome that carries the same vrn allele responded differently to vernalisation deficit. Differences have been shown between all group 5 reciprocal substitutions. Lines carrying chromosomes 5A and 5D of Mironovskaya 808 had a high vernalisation requirement whereas lines carrying chromosome 5B of Bezostaya 1 (vrn2B) had a low vernalisation requirement. The reciprocal lines had a reverse requirement. This explains the different vernalisation requirements of the original varieties: Mironovskaya 808 with a high vernalisation requirement carries two alleles (vrn1M and vrn3M) in its genotype that increase the vernalisation requirement, whereas Bezostaya 1 with a lower requirement for vernalisation contains only one such allele (vrn2B). By combination of the alleles in the lines with the substitution of chromosome 5B carrying vrn2 allele that in both original genotypes work inversely to the other alleles, transgressive genotypes have been formed: genotype vrn1M vrn2B vrn3M determines a higher vernalisation requirement than original variety Mironovskaya 808, and genotype vrn1B vrn2M vrn3B determines a lower vernalisation requirement than the original Bezostaya 1. An incomplete vernalisation requirement prolonged the time to heading, with exponential dependence on the vernalisation deficit, or prevented heading altogether. The original varieties further differed in photoperiodic sensitivity (Mironovskaya 808 sensitive, Bezostaya 1 less sensitive) that also influenced the background of substitution lines. The impact of the background on the heading time showed itself by about one week difference between Mironovskaya 808 and Bezostaya 1 grown under 8 weeks vernalisation and normal photoperiod. The difference between the lines with Mironovskaya 808 background and the lines with Bezostaya 1 background was approximately the same and was not significantly changed in different vernalisation variants of the lines. This difference may be caused by different photoperiodic sensitivity of the original varieties, but also by other genes, such as genes of earliness per se. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
115.
We investigated the effect of feeding habits on the fatness (length–weight relationship (LW)) and otolith growth of age‐0 Pacific bluefin tuna (PBF) (fork length (FL) of 15.0–29.9 cm) collected off the southwestern Pacific coast of Japan from July to August during 2010–2015. The feeding rate on Clupeiformes (FRc) was substantially influenced by the path of the Kuroshio Current during early summer. We suggest that the following patterns occurred in the feeding habits of PBF. In 2012 and 2014, the short distance from the coast to the Kuroshio provided high overlap between PBF and Clupeiformes and increased the opportunity for feeding, and this pattern likely caused the observed diet shift from Crustacea to Clupeiformes by smaller PBF in the studied years than those in other years. In 2011 and 2015, the encounter probability for Clupeiformes might have been low due to the long distance to the Kuroshio Current, which led PBF to actively consume non‐Clupeiformes Teleostei. In contrast, in August 2010 and 2015, PBF did not encounter Clupeiformes or other Teleostei and may have been forced to feed on a large number of Crustacea; this effect was likely due to high water temperatures. Despite the interannual fluctuation in the timing of the diet shift and the feeding intensity (FI), these factors did not contribute to growth in length; rather, they contributed to fatness. Considering size‐dependent mortality in the larval stage, these results suggest that only fast‐growing individuals survive, even if the feeding conditions drastically change.  相似文献   
116.
Soybean seed protein and oil concentrations are important traits that directly affect the quality of soyfoods. Many studies and breeding programmes have been conducted to find major quantitative trait loci (QTL) that regulate protein and oil concentrations and to develop soybean cultivars with high protein and/or oil content. The purpose of this study was to identify these QTL using a selected breeding population. The population was tested in field conditions over a period of 3 years. Seed protein and oil concentrations were measured each year. Single‐nucleotide polymorphisms (SNPs) were used to construct genetic map using a 180K SoyaSNP array, which identified 1,570 SNPs. We identified 12 QTL for seed protein, 11 for seed oil concentration and four for both traits. Among these, 17 QTL were closely mapped to previously reported QTL, whereas ten sites were novel. Several QTL were detected across at least two experimental years. These loci are good candidate QTL for optimal seed protein and oil concentrations. Our results demonstrate that favourable target QTL can be successfully identified using selected breeding populations.  相似文献   
117.
Journal of Crop Science and Biotechnology - Oat (Avena sativa L.) is one of the world’s most important cereal crops, owing to its use as an important source of essential nutrients for both...  相似文献   
118.
The Cd status of animals is best reflected by kidneys and much worse by liver and hair. Breed (heavy- and warm-blooded horses) only took an insignificant effect on the Cd content of kidneys and liver. On the average, however, warm-blooded horses stored more Cd than heavy ones. Geldings from Cd-exposed living areas accumulated insignificantly more Cd in liver, kidneys and hair than mares. The influence of age on the Cd content of kidneys and liver of Cd-exposed horses was significant. The Cd exposure of a living area was very well reflected by kidneys and liver. On the average, horses from two areas with nonferrous metal smelting stored 1000 mg Cd/kg kidney dry matter and 100 to 200 mg Cd/kg liver dry matter. The highest Cd concentration of the kidneys of horses amounted to 2.6 and 2.3 g/kg dry matter, resp.  相似文献   
119.
An alternative strategy to reduce the percolation threshold of carbon black (CB) in polymer blends was investigated using random copolymer ternary blends of polystyrene (PS), poly(methyl methacrylate) (PMMA), and a styrene-methyl methacrylate random copolymer (SMMA). The target morphology was to selectively locate CB particles in the encapsulating layer of SMMA during melt mixing. The CB used in this study is BP-2000 from Cabot and has a strong selective affinity to PS. Even when the CB was premixed with SMMA, it moves to the PS phase during the melt mixing. However, we also observed the CB particles located at the interface between SMMA and PS phases. Through this study it is found that the interaction between polymers and CB particles is critical for selectively localizing CB particles in multi-component polymer blends. Although appropriate processing condition may retard the movement of CB particles to the polymer phase with affinity, it cannot prevent it completely and locate them to the SMMA phase, which is not thermodynamically favored. To locate CB particles in an encapsulating layer of ternary polymer blends, first of all, polymers forming it should have selective affinity to CB.  相似文献   
120.
Two kinds of barley genotypes with various water‐stress tolerances, tolerant Cam/B1 and sensitive Maresi, were subjected to 10‐day soil‐drought stress in seedling and flag leaf developmental phases. After this time, both genotypes regardless of the growth stage showed a decrease in quantum yield of PSII photochemistry (ΦPSII) upon stress treatment; however, this effect was stronger in the sensitive plants than in the tolerant ones. The drought stress in the flag leaf stage was associated with an increase in superoxide dismutase (SOD) level in both genotypes, whereas in seedlings, this effect was observed only for Maresi. The activity of other enzymes (catalase and peroxidase) was changed only in small degree. An increase in proline levels and activities of Δ1‐pyrroline‐5‐carboxylate synthetase (P5CS) and ornithine delta‐aminotransferase (OAT) were observed independently of genotype and the phase of plant development, whereas the activity pyruvate dehydrogenase (PDH) decreased in tolerant genotype. Moreover, changes in the concentration of monocarbohydrates (glucose and fructose) and dicarbohydrates (saccharose, raffinose and maltose) were found: in seedlings, the amount of all soluble sugars increased, while in flag leaves decreased. The drought treatment resulted in a drop in starch level in the tolerant genotype, but in the sensitive one, the content of this substance increased in both developmental stages. EPR studies allowed the determination of the amount and character of organic radicals present in leaves. In control conditions, the content of these radical species was higher in the sensitive genotype than in tolerant one and decreased upon water stress, with the exception of flag leaves of the sensitive plant. Simulation procedure revealed four types of signals in the EPR spectra. One of them was attributed to a chlorophyll a cation and decreased upon drought. The second, ascribed to semiquinone radicals, reflected the redox balance disturbed by water deficit. The two remaining signals were connected with carbon‐centred radicals situated in the carbohydrate matrix. Their number was correlated with starch concentration.  相似文献   
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