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61.
This study investigated whether reducing agents such as quercetin and iron(II) facilitate formation of nitric oxide (NO) gas from orally ingested nitrite in an vivo study. When 3 mg/kg Na (15)NO2 was orally administered to rats with or without iron(II) or quercetin, Hb (15)NO, which is indicative of systemic (15)NO, was detected in the blood, with the maximum blood concentration of Hb (15)NO at 15 min after nitrite or nitrite plus quercetin treatment, whereas after administration of nitrite plus iron(II) or nitrite plus iron(II) and quercetin, the time was shortened to 10 min. Interestingly, iron(II), quercetin, or iron(II) plus quercetin did not affect the total amount of Hb (15)NO generated from orally administered Na (15)NO2. However, the systemic nitrite concentration was significantly decreased in the presence of iron(II) or iron(II) plus quercetin. These results may indicate that iron(II) is critical to the generation of NO gas from nitrite, whereas quercetin contributed little under the in vivo experimental conditions.  相似文献   
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In early August 2010, lacquer trees (Toxicodendron vernicifluum) severely damaged by a root rot disease were found on plantations in Iwate, Japan. The causal agent was a fungus identified as Rosellinia necatrix, based on morphology and the sequence of the ribosomal DNA internal transcribed spacer region. The fungus was clearly pathogenic on T. vernicifluum root plantings. This report is the first of white root rot on T. vernicifluum.  相似文献   
63.
Porphyromonas gulae, a gram-negative black-pigmented anaerobe, is a pathogen for periodontitis in dogs. An approximately 41-kDa fimbrial subunit protein (FimA) encoded by fimA is regarded as associated with periodontitis. In the present study, the fimA genes of 17 P. gulae strains were sequenced, and classified into two major types. The generation of phylogenetic trees based on the deduced amino acid sequence of FimA of P. gulae strains along with sequences from several strains of Porphyromonas gingivalis, a major cause of human periodontitis, revealed that the two types of FimA (types A and B) of P. gulae were similar to type I FimA and types II and III FimA of P. gingivalis, respectively. A PCR system for classification was established based on differences in the nucleotide sequences of the fimA genes. Analysis of 115 P. gulae-positive oral swab specimens from dogs revealed that 42.6%, 22.6%, and 26.1% of them contained type A, type B, and both type A and B fimA genes, respectively. Experiments with a mouse abscess model demonstrated that the strains with type B fimA caused significantly greater systemic inflammation than those with type A. These results suggest that the FimA proteins of P. gulae are diverse with two major types and that strains with type B fimA could be more virulent.  相似文献   
64.
The objective of this study was to investigate the antioxidant status in ruminal fluid and blood plasma among three faunated and two defaunated (protozoa‐free) cattle (average bodyweight of 225 kg), fed hay plus concentrate. The extra cellular antioxidant activity of the mixed protozoa and bacteria suspensions were also studied in vitro. The antioxidant activity was detected by means of the free radical scavenging ability. The activity (units/microbial nitrogen) of the protozoal suspension increased from 59 (0 h) to 318 (18 h), and decreased to 40 (24 h) during incubation. The activity of the bacterial suspension also increased from 111 (0 h) to 644 (18 h), and decreased to 533 (24 h). The antioxidant activity (units/mL, U/mL) in the ruminal fluid of faunated (ranging from 116 to 254) and defaunated (ranging from 66 to 110) cattle was increased after 2 h and decreased after 5 h of feeding, being significantly higher in the faunated cattle. The antioxidant activity of blood plasma (U/mL) ranged from 248 to 316 in the faunated and 121–170 in the defaunated cattle during 0–5 h after feeding, being significantly higher in the faunated cattle. Therefore, defaunation possibly causes a decrease in the antioxidant level in the ruminal fluid, and may impair the health and performance of ruminants through an oxidant–antioxidant imbalance.  相似文献   
65.
Six lactating Holstein cows were divided into two groups (n = 3) and used in a double reversal trial with three periods of 14 days each to evaluate the rumen fermentation, milk production and milk composition of cows fed brewer's grain (BG). The control diets contained 14% chopped Sudangrass hay, 24% corn silage, 18% alfalfa hay cube, 34% concentrate mixture‐1 and 10% concentrate mixture‐2 (wheat bran, soybean meal and cottonseed). In the experimental diet, wet BG replaced the concentrate mixture‐2. The protozoal population, concentration of ammonia‐N and volatile fatty acids in the ruminal fluid did not differ between the control and BG diets. The molar percentage of acetic acid was significantly higher (P < 0.05) with the BG diet at 5 h after feeding. The milk yield, the percentage of protein, lactose, solids not‐fat and somatic cell counts of milk did not differ between the two diets. The percentage of milk fat tended to increase with the BG diet. The BG diet significantly increased the proportions of C18:0 and C18:1 in milk fat (P < 0.01, P < 0.05, respectively) and tended to increase that of conjugated linoleic acid.  相似文献   
66.
Four female Sika deer (mean bodyweight, 48 kg) and three male Holstein cattle (mean bodyweight, 209 kg) were offered alfalfa hay cubes at 2% (deer) and 2.5% (cattle) of bodyweight, respectively. The digestibility of the cell walls and cell wall components (rhamnose, arabinose, xylose, mannose, galactose and glucose) in alfalfa and its retention time of the alfalfa in the digestive tract and rumen parameters were determined. Cell walls and xylose were less digestible in the deer than in the cattle (P < 0.01 and P < 0.05, respectively). The digestibility of galactose in the deer was as high as that in the cattle. The digestibility of the other sugars and total neutral sugars was numerically lower in the deer, but the differences were not significant. In the deer, mannose was most digestible, followed in order by galactose, arabinose, glucose, rhamnose and xylose; whereas, in the cattle, mannose was most digestible, followed in order by arabinose, glucose, galactose, rhamnose and xylose. The retention time in the digestive tract was shorter in the deer than in the cattle. In the deer, the number of ruminal protozoa was somewhat higher, and the concentrations of propionic acid and butyric acid were higher (P < 0.05) than in the cattle. These results indicate that Sika deer might utilize pectic polysaccharides as a carbon source in preference to glucose containing polysaccharides such as cellulose. The lower digestibility of all cell wall components except galactose in the Sika deer might be mainly due to its shorter retention time.  相似文献   
67.
Lomefloxacin is a broad-spectrum fluoroquinolone antibiotic used for the treatment of bacterial extraocular disease. This study investigated the efficacy and safety of lomefloxacin eye drops for bacterial extraocular disease in horses. Lomefloxacin ophthalmic solution (0.3%) was instilled three times daily for 2–5 days in 65 horses diagnosed with bacterial extraocular disease based on clinical findings. Clinical observations and bacteriological examinations were performed at the start of treatment, 2 and 5 days after the start of treatment, and at the discontinuation or termination of treatment. Of the 65 horses, 64 were positive for bacteria, and 22 bacterial genera and 47 bacterial species were identified. The efficacy of lomefloxacin was evaluated in 63 horses; one horse with a negative culture and another with suspected bacterial contamination were excluded. Lomefloxacin was considered to be clinically effective in 54 horses. The major bacterial species identified were Staphylococcus aureus, Streptococcus equi subsp. zooepidemicus, Acinetobacter lwoffii, Staphylococcus xylosus, Staphylococcus vitulinus, Enterobacter agglomerans, Flavimonas oryzihabitans and Staphylococcus sciuri, with a cumulative disappearance rate of 80% or more at the termination of instillation. Excluding one horse that did not undergo a bacteriological examination, the remaining 62 horses were assessed for bacteriological outcome. Full or partial bacterial clearance was detected in 95% or more of the 62 horses. One of the 65 horses reported adverse events that had no causal relation with the eye drops. Our results showed that lomefloxacin is safe and effective for the treatment of bacterial extraocular disease in horses.  相似文献   
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