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91.
The present study assessed the effects of intramammary infusion of Bifidobacterium breve (B. breve) on mastitis‐causing pathogens and on the somatic cell counts (SCC) in lactating cows with chronic subclinical mastitis. The bacteriological cure rates of 42 quarters from 42 cows infected with Staphylococcus aureus, Corynebacterium bovis, coagulase‐negative staphylococci, and environmental streptococci were 18.2% (2/11), 14.3% (1/7), 58.8% (10/17), and 28.6% (2/7), respectively, on day 14 after B. breve infusion. In a second trial, B. breve was infused into 18 quarters from 18 cows with chronic subclinical mastitis from which pathogens had not been isolated; the rates of quarters showing SCC > 50 × 104 cells/ml prior to B. breve infusion that decreased to < 30 × 104 cells/ml after infusion were significantly (p < .01) increased to 61.1% (11/18) on day 14 compared to that prior to infusion (0/18). The intramammary infusion of B. breve appears to be a non‐antibiotic approach for elimination of minor pathogens and decreasing SCC in quarters with chronic subclinical mastitis in dairy cows.  相似文献   
92.
This study was conducted to evaluate the changes in acute-phase proteins and cytokine concentrations in dairy cows with naturally occurring peracute Klebsiella pneumoniae (K. pneumoniae) mastitis and their association with the outcome of the disease. Seventeen Holstein cows with K. pneumoniae mastitis from 8 dairy farms were divided on the basis of outcome after local and systemic therapy into 2 groups comprising 8 euthanized cows and 9 that recovered. Changes in acute-phase proteins and cytokine concentrations in cows with K. pneumoniae mastitis were evaluated at the onset of the disease (day 0) and at days 3, 7 and 14 after therapy and compared with those of 13 healthy dairy cows. The concentrations of haptoglobin (Hp) and interleukin (IL)-6 in serum and α(1)-acid glycoprotein and IL-1β in serum and whey on day 0 were significantly (P<0.05) higher in the euthanized cows than in those that recovered and the healthy cows. A correlation (r=0.90, P<0.01, n=17) was found between IL-6 and Hp concentrations in sera from recovered and euthanized cows at day 0. This indicated that serum concentrations of Hp and IL-6 at the initial examination were prognostic factors for survival, and the cutoff values were 2,020 μg/ml and 32 ng/ml, respectively. These results suggest that IL-6 and Hp concentrations are involved in the manifestation of K. pneumoniae mastitis and may be possible indicators of the prognosis of peracute K. pneumoniae mastitis.  相似文献   
93.
Holocellulose samples prepared from transgenic poplars overexpressing xyloglucanase had crystal widths of 3.2–3.5 nm as a result of the (2 0 0) plane, based on their X-ray diffraction patterns, and crystal widths were greater than those of the wild type (3.0 nm). Cellulose microfibril widths in the holocellulose samples were further determined from transmission electron microscopic (TEM) images of individualized fibrils prepared by 2,2,6,6-tetramethylpiperidine-1-oxy radical-mediated oxidation of the holocelluloses and the successive disintegration of the oxidized products in water. The TEM images also supported the finding that cellulose microfibril widths of transgenic poplars were larger than those of the wild type. The cellulose microfibril widths of transgenic poplars were approximately 6 nm, whereas those of the wild type were about 5 nm. However, such enlargement of cellulose microfibril widths could not be explained by the increased cellulose contents of the transgenic poplars alone.  相似文献   
94.
Absorption and metabolism of a natural compound, 6-O-caffeoylsophorose (CS) from acylated anthocyanins in a red vinegar fermented with purple sweet potato, were clarified. The absorption of CS and conjugated CS in blood from orally administrated Sprague-Dawley rats at a dose of 400 mg/kg was investigated by electrochemical detection-high performance liquid chromatography. As a result, CS was successfully detected in rat plasma (AUC(0-6h), 108.6 ± 8.1 nmol h/mL) and was found to be an intact absorbable polyphenol. In addition, half of the absorbed CS was detected as its conjugates (AUC(0-6h), 50.7 ± 5.7 nmol h/mL) as well as caffeic and ferulic acids from CS. By a time-of-flight-mass spectrometric analysis of CS-administered plasma sample, glucuronide and methylated conjugates of CS were identified, in addition to glucuronide, methylated, or sulfate conjugates of caffeic and ferulic acids. Consequently, CS was absorbed in intact form into rat blood and partly degraded to caffeic and ferulic acids or metabolized by glucuronidation, methylation, or sulfatation.  相似文献   
95.
ABSTRACT:   The installation depth of the hook in longline fishing gear has previously been measured with micro depth loggers. Research that assumes the catenary shape of longline fishing gear by a simulation based on these data has been done. However, it was not known whether the branch line was tangled with the main line or flowed with the current. In this research, an ultrasonic positioning system generally used to investigate the underwater behavior of marine organisms, and a buoy with a communications satellite, have been used, and the 3-dimensional underwater shape of tuna longline fishing gear was measured. It was possible to monitor changes in fishing gear in real time. The possibility of high precision measurement was suggested with future technical improvement.  相似文献   
96.
ABSTRACT:   The effect of taurine on growth of yellowtail juveniles Seriola quinqueradiata was investigated by a feeding experiment of diets containing various taurine levels. Test diets supplemented with 0, 0.5, 1.0, 1.5 and 2.0% of taurine were prepared. These diets were fed to yellowtail juveniles with an initial mean body weight of 0.5 g for 6 weeks. Supplementation of taurine in the diet of yellowtail improved their growth performance significantly ( P  < 0.05) over the initial 3-week period. The fish fed with the taurine-supplemented diet improved in percent gain and feed efficiency over both 3 and 6 weeks. Taurine content in the muscle proportionally increased with the dietary taurine level. The fish fed without supplemented taurine diet showed higher contents of serine in the muscle. With each increase in the inclusion level of taurine content in the diet, the concentration of serine in the muscle decreased. The cystathionine content in the muscle of each group was unchanged. These results suggest that taurine supplementation in the diet not only improves growth but also affects the sulfur amino acid metabolism of yellowtail juveniles.  相似文献   
97.
98.
Even though tetrodotoxin (TTX) is a widespread toxin in marine and terrestrial organisms, very little is known about the biosynthetic pathway used to produce it. By describing chemical structures of natural analogs of TTX, we can start to identify some of the precursors that might be important for TTX biosynthesis. In the present study, an analog of TTX, 5,11-dideoxyTTX, was identified for the first time in natural sources, the ovary of the pufferfish and the pharynx of a flatworm (planocerid sp. 1), by comparison with totally synthesized (−)-5,11-dideoxyTTX, using high resolution ESI-LC-MS. Based on the presence of 5,11-dideoxyTTX together with a series of known deoxy analogs, 5,6,11-trideoxyTTX, 6,11-dideoxyTTX, 11-deoxyTTX, and 5-deoxyTTX, in these animals, we predicted two routes of stepwise oxidation pathways in the late stages of biosynthesis of TTX. Furthermore, high resolution masses of the major fragment ions of TTX, 6,11-dideoxyTTX, and 5,6,11-trideoxyTTX were also measured, and their molecular formulas and structures were predicted to compare them with each other. Although both TTX and 5,6,11-trideoxyTTX give major fragment ions that are very close, m/z 162.0660 and 162.1020, respectively, they are distinguishable and predicted to be different molecular formulas. These data will be useful for identification of TTXs using high resolution LC-MS/MS.  相似文献   
99.
Identification of new tetrodotoxin (TTX) analogs from TTX-possessing animals might provide insight into its biosynthesis and metabolism. In this study, four new analogs, 8-epi-5,6,11-trideoxyTTX, 4,9-anhydro-8-epi-5,6,11-trideoxyTTX, 1-hydroxy-8-epi-5,6,11-trideoxyTTX, and 1-hydroxy-4,4a-anhydro-8-epi-5,6,11-trideoxyTTX, were isolated from the newt, Cynops ensicauda popei, and their structures were determined using spectroscopic methods. These are the first 8-epi-type analogs of TTX that have been found in a natural source. Furthermore, we examined the composition of the TTX analogs in this newt and in the ovary of the puffer fish, Fugu poecilonotus, using LC/MS. The results indicate that TTX and 11-deoxyTTX were present in both sources. However, 6-epiTTX and 8-epi-type analogs were detected only in the newt, while 5,6,11-trideoxyTTX was a specific and major analog in the puffer fish. Such considerable differences among analog compositions might reflect differences in the biosynthesis or metabolism of TTX between these animals.  相似文献   
100.
The cause of abnormal musculature on both sides of the same myotome in artificially cultured seven‐band grouper Epinephelus septemfasciatus (Thunberg) larvae remains unclear. We evaluated the effect of three factors: changes in temperature (between 22 and 24°C), disinfection with ozonated seawater (0.3 mg TROs L?1, 1 min), and hypoxia (22 or 14% saturation) during the early (20 h post‐fertilization, hpf) and mid‐ (24 hpf) somite stages on trunk muscular development in larval seven‐band grouper. The thermal regimes and disinfection with ozonated seawater had no effect on muscle development (P > 0.05, G‐test). In contrast, exposure to hypoxia during both the early and mid‐somite stages increased the incidence of abnormal musculature in the trunk (P < 0.01, G‐test). These larvae had abnormal musculature on both sides of the trunk. In addition, the number of abnormal myotomes differed among these larvae. Exposure in the early and mid‐somite stages resulted in the highest frequency of abnormalities in the 11th and 13th myotome respectively. Our results suggest that hypoxia during somitogenesis can lead to abnormal muscle development in the trunk of artificially cultured seven‐band grouper larva.  相似文献   
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