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41.
We investigated the changes in the plasma concentrations of oxidative stress markers in periparturient dairy cows in hot conditions. This study was performed on 10 cows from day ?5 to day 10 after parturition. The experimental duration was divided into three periods: period 1 (5 days before parturition); period 2 (5 days after parturition); and period 3 (from day 6 to day 10 after parturition). The average rectal temperature in the cows during the experimental period was more than 39°C. Plasma aspartate aminotransferase activities in periods 2 and 3 were higher than that in period 1 (P < 0.05). Blood urea nitrogen concentration in period 3 was lower than those in periods 1 and 2 (P < 0.05). The total ascorbic acid concentration in the plasma in period 2 was greater than those in periods 1 and 3 (P < 0.05). Thiobarbituric acid reactive substances (TBARS) concentrations in periods 2 and 3 were greater than that in period 1 (P < 0.05). TBARS concentration was positively correlated with aspartate aminotransferase activity (P < 0.05). These results suggested that oxidative stress increased in cows after parturition under hot climatic conditions. 相似文献
42.
Nakai M Fukui Y Asami S Toyoda-Ono Y Iwashita T Shibata H Mitsunaga T Hashimoto F Kiso Y 《Journal of agricultural and food chemistry》2005,53(11):4593-4598
Fifty-four polyphenols isolated from tea leaves were evaluated for their inhibitory activities against pancreatic lipase, the key enzyme of lipid absorption in the gut. (-)-Epigallocatechin 3-O-gallate (EGCG), which is one of major polyphenols in green tea, showed lipase inhibition with an IC50 of 0.349 microM. Moreover, flavan-3-ol digallate esters, such as (-)-epigallocatechin-3,5-digallate, showed higher activities of inhibition on lipase with an IC50 of 0.098 microM. On the other hand, nonesterified flavan-3-ols, such as (+)-catechin, (-)-epicatechin, (+)-gallocatechin, and (-)-epigallocatechin, showed zero and/or the lowest activities against pancreatic lipase (IC50 > 20 microM). These data suggested that the presence of galloyl moieties within the structure was required for enhancement of pancreatic lipase inhibition. It is well-known that flavan-3-ols are polymerized by polyphenol oxidase and/or heating in a manufacturing process of oolong tea. Oolonghomobisflavans A and B and oolongtheanin 3'-O-gallate, which are typical in oolong tea leaves, showed strong inhibitory activities with IC50 values of 0.048, 0.108, and 0.068 microM, respectively, even higher than that of EGCG. The oolong tea polymerized polyphenols (OTPP) were prepared for the assay from oolong tea extract, from which the preparation effectively subtracted the zero and/or less-active monomeric flavan-3-ols by preparative high-performance liquid chromatography. The weight-average molecular weight (Mw) and number-average molecular-weight (Mn) values of OTPP were 2017 and 903, respectively, by using gel permeation choromatography. OTPP showed a 5-fold stronger inhibition against pancreatic lipase (IC50 = 0.28 microg/mL) by comparison with that of the tannase-treated OTPP (IC50 = 1.38 microg/mL). These data suggested that the presence of galloyl moieties within their chemical structures and/or the polymerization of flavan-3-ols were required for enhancement of pancreatic lipase inhibition. 相似文献
43.
Hiroshi KAGAMI Jun YASUDA Takahiro TAGAMI Mitsuru NAITO Yuko MATSUBARA Takashi HARUMI Takamasa NOGUCHI Yasuhiro YAMAMOTO Taikai TAKAHASHI Junichi MATSUYAMA Hiroyuki KOMATSU Tamao ONO 《Animal Science Journal》2002,73(6):453-456
Effect of the strain combination of the donor and recipient on production efficiency of W‐bearing sperm in mixed‐sex chimeric testes was analyzed. The combinations of the donors and recipients were White Leghorn (WL) and Rhode Island Red (RIR), and vice versa. Generated mixed‐sex chimeras that had the male phenotype at sexual maturity were classified into four groups: (1) a female WL donor and a male RIR recipient; (2) a male WL donor and a female RIR recipient; (3) a female RIR donor and a male WL recipient; (4) a male RIR donor and a female WL recipient. The mean number of W‐bearing sperm detected by in situ hybridization among 10 000 sperm observed were 147, 165, 30 and 45 in groups 1, 2, 3 and 4, respectively. The numbers in groups 1 and 2 were both significantly higher than those of groups 3 and 4 (P < 0.05). The combination of a WL donor and a RIR recipient produced W‐bearing sperm more efficiently than the reverse combination. 相似文献
44.
Uchida Y Ike K Katayama N Oguni Y Imai S 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2005,67(5):539-542
Interleukin 10 (IL-10) genes of Djungarian, Chinese, and Syrian hamsters were cloned. The clones of IL-10 consisted of 537 bp nucleotides and 178 amino acids in full length, and the nucleotide and amino acid sequences exhibited a high degree of homology with those of the mouse and human. Since the number and position of signal sequences, N-glycosylations and cysteine sites in the IL-10 amino acid sequences of the hamsters were the same as those of the mouse, we suggest that the IL-10 molecular structures of the hamster are closer to that of the mouse than human. 相似文献
45.
Watanabe Y Kimura K Yang CH Ooi HK 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2005,67(12):1285-1287
A survey on the presence of Cryptosporidium oocyst and Giardia cyst in livestock drinking water as well as the urban tap water throughout Taiwan was carried out. Water examination for the presence of the protozoa was conducted by filtering through a PTFE membrane followed by immunomagnetic separation (IMS) and immunostaining the sediment with commercially available monoclonal antibody against Cryptosporidium and Giardia. Of the 55 different water samples from various sources examined, 2 were found to contain both of Cryptosporidium oocyst and Giardia cyst, 1 was found to contain Cryptosporidium oocyst only. These protozoa-positive water samples, originating from underground well and from the mountain spring, were also used as drinking water for livestock. However, no Cryptosporidium oocyst was found in the city tap water. This is the first report of Cryptosporidium oocyst and Giardia cyst being found in the drinking water for livestock. 相似文献
46.
Tajima Y Hayashi Y Yamada TK 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2004,66(7):761-766
Morphology of the modern cetaceans represents the results of adaptation of the ancestral terrestrial mammals to aquatic life through their evolutional processes. Some of the primitive fossil cetaceans are known to have both fore and hind limbs, whereas the pelvic bones of modern cetaceans are, in general, a pair of slender rod-like structures within the abdominal wall muscles just anterior to the anus with no articulations to the axial skeleton in both sexes. It is interesting and important to consider the causes and processes of how the hind limbs were lost and how the pelvis was reduced during the process of adaptation. In the present study, we tried to evaluate the topography and function of rudimentary pelvic bones of the finless porpoise (Neophocaena phocaenoides), one of the members of the odontocete cetaceans, with special references to the structures around the pelvic bones. Some soft tissues such as M. ischiocavernosus relating to the pelvic bone are transformed following the drastic reduction of the pelvis. This transformation tells us that the cetaceans adapted to the aquatic life during evolutional processes chose the tail flukes driven by the powerful trunk muscles for locomotion, instead of modifying the hind limbs into hind flippers as seen in pinnipeds. On the other hand, it is evident that a function of the pelvic bones of the male finless porpoise was supporting the penis as those of terrestrial mammals. It is noteworthy that the morphological features of the ancestral terrestrial mammals can be traced when they are carefully compared with those of the finless porpoise. 相似文献
47.
48.
Induction of feline immunodeficiency virus from a chronically infected feline T-lymphocyte cell line
The infection of the feline T-lymphocyte cell line FeT-J with the feline immunodeficiency virus (FIV) Petaluma strain led to the establishment of nonvirus-producing cells. One clone (C15) obtained by limiting dilution was found to express FIV in response to chemical inducers of retroviruses. The chemical treatment of C15 cells led to not only FIV protein synthesis but also an augmentation of viral production. Examination of the C15 cell derivatives obtained by recloning revealed that 10-40% of treated cells constitutively expressed FIV antigens, whereas 100% with expressed FIV antigen in response to the inducer. Chemical induction resulted in more than a 100-fold increase in infectious viral production. The results suggest that a majority of FeT-J cells that are infected with FIV exist in a non-productive state. Establishing a cell line that can be non-productively infected by FIV may help determine the mechanisms of FIV latency. 相似文献
49.
Fujimoto Y Nakatani N Kubo T Semi Y Yoshida N Nakajima H Iseri T Azuma YT Takeuchi T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2012,74(1):27-34
Macrophages are essential for controlling the majority of infections, and are mediators of natural immunity. During infection, lipopolysaccharide (LPS) stimulates macrophages to produce pro-inflammatory cytokines. Adenosine and ATP released into the extracellular space by immunological stimuli have been shown to regulate various immune functions. More recently, it has been shown adenosine and ATP have a critical role on the physiological negative feedback mechanism for limitation and termination of tissue-specific and systemic inflammatory responses. It was useful and meaningful to gain information about interaction between LPS, which generates the inflammation, and adenosine and ATP, which terminate the inflammation. We evaluate effects of adenosine and ATP on the production of cytokines related to inflammation in canine macrophage cell line DH82 cells. Adenosine and ATP respectively increased the production of IL-10 without affecting the production of IL-6, TNF-α and IL-12 in DH82 cells. In addition, adenosine and ATP prevented the production of LPS-induced IL-6, TNF-α and IL-12 in DH82 cells. In contrast, adenosine and ATP potentiated LPS-induced IL-10 production in DH82 cells. Moreover, adenosine, but not ATP inhibited LPS-induced expression of TLR4 in DH82 cells. These results suggest that conditions related to increased adenosine and/or ATP may play an important role in the inflammatory reactions. 相似文献
50.
WULIJIDELIGEN Takayuki ASAHINA Kazushi HARA Kensuke ARAKAWA Hiroyuki NAKANO Taku MIYAMOTO 《Animal Science Journal》2012,83(10):704-711
The purification and characterization of a bacteriocin produced by Leuconostoc mesenteroides strain 406 that was isolated from traditional Mongolian fermented mare's milk, airag, were carried out. Leuconostoc mesenteroides strain 406 was identified on the basis of its morphological and biochemical characteristics and carbohydrate fermentation profile and by API 50 CH kit and 16S ribosomal DNA analyses. The neutral‐pH cell‐free supernatant of this bacterium inhibited the growth of several lactic acid bacteria and food spoilage and pathogenic organisms, including Listeria monocytogenes and Clostridium botulinum. The bacteriocin was heat‐stable and not sensitive to acid and alkaline conditions, but was sensitive to several proteolytic enzymes such as pepsin, pronase E, proteinase K, trypsin, and α‐chymotrypsin, but not catalase. Optimum bacteriocin production (4000 activity units/mL) was achieved when the strain was cultured at 25°C for 24–36 h in Man Rogosa Sharpe medium. The bacteriocin was partially purified by ammonium sulfate precipitation (80% saturation), dialysis (cut‐off MW: 1000), and gel filtration chromatography. Sodium dodecyl sulfate‐polyacrylamide gel electrophoresis revealed that the bacteriocin had a molecular weight of approximately 3.3 kDa. To our knowledge, this is the first report of the isolation of a bacteriocin‐producing Leuconostoc strain from airag. An application to fermented milks would be desired. 相似文献