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The present study aimed to clarify changes of oxidative stress and antioxidative functions in treadmill-exercised Thoroughbred horses (n=5, 3 to 7 years old), using recently developed techniques for measurement of serum d-ROMs for oxidative stress, and BAP for antioxidative markers. Also, the effect of nasogastric administration of hydrogen-rich water (HW) or placebo water preceding the treadmill exercise on these parameters was examined. Each horse was subjected to a maximum level of treadmill exercise in which the horses were exhausted at an average speed of 13.2 ± 0.84 m/sec. Blood samples were taken 4 times, immediately before the intake of HW or placebo water at 30 min preceding the treadmill exercise, immediately before the exercise (pre-exercise), immediately after the exercise (post-exercise) and at 30 min following the exercise. In all horses, both d-ROMs and BAP values significantly increased at post-exercise. The increase in d-ROMs tended to be lower in the HW trial, as compared to the placebo trial at pre-exercise. The increase in BAP was considerable at approximately 150% of the pre-exercise values in both the HW and placebo treatment trials. The BAP/d-ROMs ratio was significantly elevated at post-exercise in both treatment trials, while a significant elevation was also observed at pre-exercise in the HW trial. BAP, d-ROM, and the BAP/d-ROM ratio tended to decline at 30 min after the exercise, except BAP and BAP/d-ROMs in the placebo trial. These results demonstrate that the marked elevation of oxidative stress and anitioxidative functions occurred simultaneously in the intensively exercised horses, and suggest a possibility that HW has some antioxidative efficacy.  相似文献   
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Basilaphelenchus gorganensis n. sp. is described and illustrated from wood and bark of a dead tree from northern Iran. The new species is characterized by female body length (415–559 µm), three‐lined lateral fields, a sclerotized cephalic vestibule and cephalic framework, thin stylet with three elongate backwardly directed knobs, small spherical to oval metacorpus, with small and posteriorly located valve, simple vulva without any flap apparatus, 59‐ to 79‐µm‐long post‐vulval uterine sac, functional rectum and anus and dorsally convex, ventrally concave, usually ventrally bent conical female tail with a sharp tip. Males are common, apparently functional and characterized by well‐curved spicules, three pairs of small caudal papillae and no bursa at tail tip. Molecular phylogenetic inferences using partial sequences of small and large subunit ribosomal RNA genes (SSU and LSU rDNA) from different isolates of the new species revealed it differs from currently sequenced species and belongs to the Tylaphelenchinae clade.  相似文献   
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Episodes of summer mortality of the Kumamoto oyster Crassostrea sikamea are a major problem for its cultivation. Expression of the heat shock protein 70 (HSP70) is induced by various environmental stresses, including heat. We cloned and sequenced hsp70 complementary DNA from C. sikamea to investigate the relationship between hsp70 expression and heat tolerance in this oyster. Quantitative real-time polymerase chain reaction was performed using gill tissue dissected from oysters before and after heat shock for 1 h. The results showed hsp70 expression was faster and greater in oysters cultured at 20–22 °C than at 10–12 °C, and survival was lower among oysters cultured at 20–22 °C than at 10–12 °C. Moreover, heat tolerance was investigated by a 1-h pre-heat treatment, followed by exposure to heat shock conditions 5 days later. Survival was higher and hsp70 expression was notably lower in oysters that received the pre-heat treatment compared with those that did not. We conclude that a pre-heat treatment of only 1 h may be useful for inducing heat tolerance in C. sikamea, and that a low level of hsp70 expression after heat shock is an important index in selecting for high heat tolerance in these oysters.  相似文献   
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Photocrosslinked hydrogels reinforced by microfibrillated cellulose (MFC) were prepared from a methacrylate-functionalized fish elastin polypeptide and MFC dispersed in dimethylsulfoxide (DMSO). First, a water-soluble elastin peptide with a molecular weight of ca. 500 g/mol from the fish bulbus arteriosus was polymerized by N,N′-dicyclohexylcarbodiimide (DCC), a condensation reagent, and then modified with 2-isocyanatoethyl methacrylate (MOI) to yield a photocrosslinkable fish elastin polypeptide. The product was dissolved in DMSO and irradiated with UV light in the presence of a radical photoinitiator. We obtained hydrogels successfully by substitution of DMSO with water. The composite gel with MFC was prepared by UV irradiation of the photocrosslinkable elastin polypeptide mixed with dispersed MFC in DMSO, followed by substitution of DMSO with water. The tensile test of the composite gels revealed that the addition of MFC improved the tensile properties, and the shape of the stress–strain curve of the composite gel became more similar to the typical shape of an elastic material with an increase of MFC content. The rheology measurement showed that the elastic modulus of the composite gel increased with an increase of MFC content. The cell proliferation test on the composite gel showed no toxicity.  相似文献   
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Rutin is one of the flavonoids derived from plants such as buckwheat and is well known as a powerful antioxidant. To determine whether dietary rutin could modulate mucosal immunity, we examined the gene expression of Th1/Th2 cytokines and the receptors in the gut and lung. Aged (18 months old, 18 M) C3H/HeN female mice were orally administered rutin for 10 days. The small intestine and lung were taken and analyzed by real-time PCR for gene expression. Interleukin (IL)-13 and IL-13Rα2 gene expression was significantly low (P<0.05 respectively) in the small intestine of aged rutin-fed mice. Meanwhile, there was no change in interferon γ gene expression between control and rutin-fed mice. IL-13 gene expression was also downregulated in the lung. To examine the mechanism of the inhibitory effect of rutin on Th2 cytokines in aged mice, intestinal nitric oxide synthase (NOS) expression was evaluated. Rutin inhibited inducible NOS (NOS2) gene expression, but not neuronal NOS and endothelial NOS. Gene analysis of cells collected from the small intestine by laser capture dissection revealed that NOS2 expression was significantly inhibited in crypt regions. Thus, rutin might be effective against a Th2-dominant profile through NOS2 inhibition in aged mice.  相似文献   
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The objective of this study was to investigate the profiles of hair cortisol concentrations as an index of chronic stress in dairy cows in association with their health, nutrition, and reproductive parameters. For 25 Holstein dairy cows, hair was collected from the tail switch ?19.2 ± 11.4, 44.8 ± 11.9, 103.0 ± 9.9, and 168.0 ± 9.7 days postpartum (L0, L1, L2, and L3, respectively). Body condition scores were negatively correlated with hair cortisol concentrations (r = ?0.255), and hock health scores were positively correlated with hair cortisol concentrations (r = 0.236, p < 0.05). Hair cortisol concentrations during the postpartum period showed different patterns according to the time of first artificial insemination (AI) and fertility. Cows that were submitted to first AI by 86 days postpartum showed a peak hair cortisol concentration at L1, whereas cows with delayed first AI had a peak at L2. The hair cortisol concentrations of subfertile (≥168 days) cows were significantly higher at L1 and L2 compared with L0, whereas hair cortisol concentrations of fertile cows (<168 days) were not different among the sampling times. These results indicate that cows with health problems appear to experience greater chronic stress, which may impair their reproductive function.  相似文献   
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