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201.
Although feline idiopathic cystitis (FIC) distresses of many cats, its pathogenesis is unknown and the diagnosis is challenging. Polyunsaturated fatty acids (PUFAs) are metabolized into various lipid mediators. Lipid mediators such as prostaglandins (PGs) modulate inflammation and many of them are excreted into the urine. Thus, the investigation of the urinary lipid profile may reveal pathogenesis and help diagnosis of FIC. We collected urine samples from five FIC cats by spontaneous urination and analyzed 158 types of lipid mediators in urines using liquid chromatography-mass spectrometry. The urinary levels of PUFAs were higher in FIC compared to those of the healthy group. The excretions of a major inflammatory mediator, PGD2, were less in FIC. Other well-known inflammatory mediators such as PGE2, PGI2, and their metabolites did not show a difference. In contrast, the levels of PGF and its 2 metabolites and PGF were higher in FIC. These results may provide new insights into the future management of cat FIC.  相似文献   
202.
Serological analysis was performed to detect morbillivirus infection in Kuril harbor seals in Hokkaido, Japan. Serum samples were collected from the seals at Nosappu (231 sera), Akkeshi (16), and Erimo (75) between 1998 and 2005. Antibodies to phocine distemper virus (PDV) were detected by ELISA in seals from Nosappu and Erimo. Antibodies to PDV were found in 56% (5/9) of the sampled seals from Nosappu in 1998, versus only 5% (3/66) for 2003, 1% (1/79) for 2004, and 1% (1/77) for 2005. These suggest epidemic caused by the virus in or before 1998. As antibody-positive seals included juvenile seals in 2003 and 2005, sporadic infections of the virus are thought to have occurred in recent years. In Erimo, antibodies to PDV were found in 50% (14/28) of sampled seals in 2004, versus only 13% (1/8) for 1999, 7% (1/15) for 2003, and 0% (0/24) for 2005. These suggest sporadic infection by the virus before 2003 and the epizootic between after autumn in 2003, when samples of 2003 were collected, and 2004. Since antibodies to canine distemper virus (CDV) were detected in one adult seal from Nosappu in each year from 2003 to 2005, sporadic infections of the virus were suggested. There were no difference in incidence of seals with antibodies to the viruses between males and females and between juveniles and adults.  相似文献   
203.
The effects of hyaluronic acid, which comprises the cumulus intercellular matrix, on Ca(2+) influx, lactate dehydrogenase (LDH) activity, and cyclic AMP synthesis in canine sperm during capacitation was investigated. Ejaculated sperm were collected from 10 Beagle dogs and the sperm were incubated for 4 hr in Eagle's MEM containing 10 microg/ml of hyaluronic acid. The percentages of actively motile sperm, hyperactivated sperm (HA-sperm), acrosome-reacted sperm (AR-sperm), and sperm labeled with fluoresceinated Ca(2+) indicator (Ca(2+)-labeled sperm) were evaluated to assess Ca(2+) influx into the sperm. LDH activity and cAMP concentration were measured in homogenized sperm. The mean percentages of motile sperm, HA-sperm, and Ca(2+)-labeled sperm in the MEM containing hyaluronic acid were higher than in the control medium (P<0.05, 0.05, and 0.01, respectively), but there was no difference between the percentages of AR-sperm. Mean LDH activity and mean cAMP concentration were also significantly higher than the control values (P<0.05). The percentages of HA-sperm correlated with those of Ca(2+)-labeled sperm (r(2)=0.810). The results indicate that hyaluronic acid increases Ca(2+) influx, LDH activity, and cAMP synthesis in canine ejaculated sperm during capacitation in vitro.  相似文献   
204.
Molecular-weight distribution and characterization of tea tannin were investigated by high-performance liquid chromatography and the equivalent preparative exclusion gel chromatography using Sephadex G-25. The characteristics of the fractions were studied regarding the amounts of terminal catechin, sugar, and gallic acid, the color reaction of the Folin-Chiocalteu reagent, the UV absorbance, and the inhibition activity for the trypsin-caseinolytic activity per weight. Furthermore, we investigated the intercepting activities of the inhibition by the amino acids, peptides, their analogues, poly(ethylene glycol)s (PEGs), and histatin 5 using the inhibition of trypsin-caseinolytic activity by tea. Arg, Lys, and their peptides had strong intercepting activities for the inhibition, but only a weak activity was detected in the Pro peptides or gelatin-like peptides of (Pro-Pro-Gly)(n) (n = 5 or 10). The guanidyl group of Arg and the amino methylene group of Lys were important for the intercepting activity, but the activity was weakly dependent upon the peptide bond formation. The intercepting activity of the peptides or PEG exponentially increased with the number of polymerizations. Histatin 5 did not have a remarkably strong intercepting activity considering the peptide length. The activity of the synthetic histatin 5 in which all of the Lys and Arg were substituted by Ala was at the same level as histatin 5.  相似文献   
205.
Murata  Yuko  Saito  Ken  Sugimoto  Katashi  Kiyomoto  Masato  Unuma  Tatsuya 《Fisheries Science》2021,87(3):371-381

Hemicentrotus pulcherrimus in the Tohoku area is not utilized as a fishery product because the ovaries have a bitter taste almost all year. To discover the cause, we compared the annual reproductive cycles and ovarian accumulation of a bitter amino acid, pulcherrimine, in H. pulcherrimus collected at Mikuni (Fukui Prefecture), where it is fished in summer, and Iwaki (Fukushima Prefecture), where it is not utilized. At both sites, pulcherrimine increased in maturing ovaries as oogenesis proceeded from autumn to winter, decreased after spawning in spring, but remained in spent and immature ovaries for a few months. In Mikuni, pulcherrimine was scarcely detected in the ovaries for several months in summer. However, in Iwaki, late spawning delayed the disappearance of pulcherrimine in summer, and early initiation of oogenesis advanced the restart of pulcherrimine accumulation in autumn compared to Mikuni. Consequently, the period when the ovaries were palatable because of the absence of pulcherrimine during summer was short in Iwaki. The major cause of such short-term palatability could be the lower seawater temperature in the Tohoku area. Furthermore, pulcherrimine was never detected in other sea urchins, although a bitter taste was found in the mature ovaries of some species.

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206.
Genetic diversity of Myanmar melon was evaluated by analysis of 27 RAPD markers and morphological characters using 41 accessions of melon landraces of which 36 accessions were small-seed type. The gene diversity was 0.239, higher than for group Conomon from East Asia and equivalent to Indian melon populations. Melon accessions were classified into six major clusters. The largest cluster IV comprised mainly group Conomon which was closely related to cluster V consisting of mainly group Agrestis. Most of the accessions of group Cantalupensis were grouped into clusters II or VII and were distantly related to groups Conomon and Agrestis. The genetic relationship to melon accessions from neighboring countries was analyzed. The 24 accessions of clusters IV and V were mostly clustered together with small-seed type melon of India, but the 14 accessions of clusters VI and VII were mostly clustered together with large-seed type melon of India. These results indicated that the genetic diversity of Indian melon is conserved in Myanmar. Genetic introgression among melon groups through spontaneous hybridization was also indicated and was considered important to maintain or increase the genetic diversity in Myanmar.  相似文献   
207.
A high proportion of threatened and near-threatened species in the world now inhabit farmland. Although much data regarding the impact of agriculture on farmland biodiversity have been accumulated in Western countries, such information, particularly on the impact of rice cultivation, is fragmentary in other parts of the world and has rarely been disseminated internationally. Therefore, this paper aims to clarify what information has become available through earlier studies in Japan, where farmland mainly consists of rice paddy areas, and give directions for future studies about the impact of agriculture on farmland birds in Japan. This study made three notable observations. First, a review of earlier studies of farmland bird species in Japan uncovered some evidence of both increases (e.g., wildfowl and cranes) and declines (e.g., waders) in population size. Second, this paper closely examined case studies of two types of typical farmland birds: (1) geese and cranes foraging on crops and/or harvested remains of crops and (2) waders and egrets foraging on small organisms in farmland, not agricultural crops. This portion of the study identified some potential routes through which human activities in farmland affect bird species in Japan, and offered practical implications for conservation and management of these species supported by scientific data. Finally, based on the results of this review, three key tasks for future conservation studies and practices in Japanese farmland were suggested: (1) establishing quantitative indices based on monitoring surveys in farmland to track the population status, (2) collecting further evidence of the impact of agriculture, particularly on population-level responses by birds, and in a food-web context, and (3) applying evidence-based conservation to practice.  相似文献   
208.
The origin and transmission routes of atypical bovine spongiform encephalopathy (BSE) remain unclear. To assess whether the biological and biochemical characteristics of atypical L-type BSE detected in Japanese cattle (BSE/JP24) are conserved during serial passages within a single host, 3 calves were inoculated intracerebrally with a brain homogenate prepared from first-passaged BSE/JP24-affected cattle. Detailed immunohistochemical and neuropathologic analysis of the brains of second-passaged animals, which had developed the disease and survived for an average of 16 months after inoculation, revealed distribution of spongiform changes and disease-associated prion protein (PrP(Sc)) throughout the brain. Although immunolabeled PrP(Sc) obtained from brain tissue was characterized by the presence of PrP plaques and diffuse synaptic granular accumulations, no stellate-type deposits were detected. Western blot analysis suggested no obvious differences in PrP(Sc) molecular mass or glycoform pattern in the brains of first- and second-passaged cattle. These findings suggest failures to identify differences in mean incubation period and biochemical and neuropathologic properties of the BSE/JP24 prion between the first and second passages in cattle.  相似文献   
209.
Theileria parva (T. parva) causes East Coast fever (ECF), which is of huge economic importance to Eastern and Southern African countries. In a previous bovine model, inflammatory cytokines were closely associated with disease progression in animals experimentally infected with T. parva. The African Cape buffalo (Syncerus caffer), the natural reservoir for T. parva, is completely resistant to ECF despite a persistently high parasitaemia following infection with T. parva. Characterizing basic immunological interactions in the host is critical to understanding the mechanism underlying disease resistance in the African Cape buffalo. In this study, the expression level of several cytokines was analyzed in T. parva-infected buffaloes. There were no significant differences in the expression profiles of inflammatory cytokines between the infected and uninfected animals despite a remarkably high parasitaemia in the former. However, the expression level of IL-10 was significantly upregulated in the infected animals. These results indicate a correlation between diminished inflammatory cytokines response and disease resistance in the buffalo.  相似文献   
210.
Canine epididymal sperm was collected from the cauda epididymis using 2 different methods (flushing and mincing) to compare the qualities (the percentage of progressively motile, viable, morphologically abnormal, immature and intact acrosomes) before and after freezing and thawing. No significant difference was noted in the quality of the cauda epididymal sperm immediately after collection and after freezing-thawing between the collection methods, although the mean levels of sperm quality with the flushing method were slightly better than that of the mincing method. The flushing method is simple and free of blood contamination, although the vas deferens was too small to be perfused in only 1 dog, and our results suggest that the flushing method is preferable to the mincing method for collecting sperm from the canine cauda epididymis.  相似文献   
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