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71.
The effect of active immunization against inhibin on the response to superovulatory treatment by porcine FSH (pFSH) was investigated in cattle. Japanese black cows were sc injected with 1 mg of porcine inhibin alpha-subunit fragment (1-26) conjugated with rabbit serum albumin (inhibin-immunized group; n=14) or rabbit serum albumin alone (control group; n=12) in Freund's complete adjuvant. Booster injections (half the amount of the primary injection) were given 35 and 70 days after the primary injection. All cows were superovulated three times with pFSH. Three days after each injection of the antigen, a progesterone-releasing intravaginal device (CIDR-B) was inserted vaginally into all animals and left in place for 10 days. Forty-eight hours before CIDR-B removal, all animals were sc injected with 30 mg pFSH dissolved in 40% polyvinylpyrrolidone, and im injected with 750 microg of PGF2alpha at CIDR-B removal. Cows were artificially inseminated twice during estrus, and ova or embryos were collected 7 or 8 days after estrus. The number of corpora lutea, the number of ova or embryos and the number of transferable embryos in inhibin-immunized cows (12.1+/-1.2, 11.1+/-1.3 and 6.2+/-1.0, respectively) were significantly greater than those in the controls (8.2+/-1.0, 5.7+/-1.1 and 3.1+/-0.7, respectively). These results indicate that active immunization against inhibin enhanced ovarian response to the usual superovulatory treatment in cattle. Therefore, immunization against inhibin may be a useful approach for improving the response to superovulation in cattle.  相似文献   
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DNA fragments of 'Candidatus Mycoplasma haemominutum', a feline heamobartonella pathogen, were detected from unfed Ixodes ovatus collected from vegetation in Hokkaido, Fukushima and Yamaguchi Prefectures, and unfed Haemaphysalis flava in Yamaguchi Prefecture. This finding suggests that ixodid tick is a possible vector of 'C. Mycoplasma haemominutum'. Spiroplasma DNA was also detected from unfed I. ovatus in Hokkaido, Fukushima and Yamaguchi Prefectures. The analysis of nucleotides sequence suggested that this Spiroplasma was distinct from registered species.  相似文献   
74.
In the plant cell wall of Pisum sativum seedlings, we found an NTPase (E.C. 3.6.1.5.) with ATP-hydrolyzing activity that was regulated by an elicitor and suppressors of defense from pea pathogen Mycosphaerella pinodes. The ATPase-rich fraction was purified from pea cell walls by NaCl solubilization, ammonium sulfate precipitation, and chromatography with an ATP-conjugated agarose column and an anion-exchange column. The specific activity of the final ATPase-rich fraction increased 600-fold over that of the initial NaCl-solubilized fraction. The purified ATPase-rich fraction also had peroxidase activity and generated superoxide, both of which were regulated by the M. pinodes elicitor and suppressor (supprescins). Active staining and Western blot analysis also showed that the ATPase was copurified along with peroxidases. In this fraction, a biotinylated elicitor and the supprescins were bound primarily and specifically to ca. 55-kDa protein (CWP-55) with an N-terminal amino acid sequence of QEEISSYAVVFDA. The cDNA clone of CWP-55 contained five ACR domains, which are conserved in the apyrases (NTPases), and the protein is identical to a pea NTPase cDNA (GenBank accession AB071369). Based on these results, we discuss a role for the plant cell wall in recognizing exogenous signal molecules.  相似文献   
75.
Nuclear magnetic resonance (NMR) microscopy is a magnetic resonance imaging method with enhanced spatial resolution due to the use of a high static magnetic field and high magnetic field gradients. It is considered to be a useful tool for non-invasive and continuous investigation of tissue and organs at the histological level. In this study, we applied NMR microscopy to assessment of morphology in mouse embryos using a developmental disorder model induced by retinoic acid administration. Pregnant mice were given 50 mg/kg all-trans retinoic acid at 8.5 dpc. Embryos were collected at several time points after treatment and examined by NMR microscopy after fixation. Two-dimensional and three-dimensional spin echo sequences were used. Tissue contrast on two-dimensional images changed according to length of repetition time and echo time, and also to developmental stage of embryos. Two-dimensional and three-dimensional images nondestructively demonstrated defects in development of the skeleton and soft tissue, e.g. hypoplasia of vertebrae in the lumbar and tail regions and dysplasia of the spinal cord, in embryos exposed to retinoic acid. These morphological abnormalities were confirmed by conventional assessment after imaging. Although further improvements are required, NMR microscopy will provide a new approach for multi-parameter assessment of embryonic development under physiological and pathological conditions.  相似文献   
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77.
Feline immunodeficiency virus (FIV) infection is characterized by chronic overactivation of immune and inflammatory system, resulting in anergic state and dysfunction of immune cells. Lactoferrin (LF), a glycoprotein present in exocrine secretions and neutrophils, plays an important role in host defense system. Our previous study showed that oral administration of bovine LF (bLF) suppressed oral inflammation, improved the clinical symptoms and decreased serum gamma-globulin as a marker of inflammation in FIV-infected cats with intractable stomatitis. The anti-inflammatory effect was partly involved in regulation of neutrophil function by bLF. In this study, to clarify the relationship between anti-inflammatory effects of bLF and peripheral blood mononuclear cells (PBMC), we examined the effect of bLF on proliferation, cell cycle progression and cytokine expression in mitogen-activated PBMC. MTT [3-(4,5-dimethylthiazol-2-yl)- 2,5-diphenyl tetrazolium bromide] assay showed that bLF inhibited the concanavalin A (ConA)-induced cell proliferation in FIV-infected cats with the asymptomatic carrier and AIDS-related complex (ARC) phase. Bovine LF restored ConA-induced cell cycle progression and resulted in suppression of the induced apoptosis in feline PBMC. Real-time RT-PCR showed that bLF suppressed ConA-induced expression of interferon-gamma and interleukin-2 in cells of the ARC group regardless of the time of its addition to the medium. These results suggest the hypothesis that therapy with bLF may have the potential to improve and protect functions of overactivated lymphocytes by modulating the cell proliferation, cell cycle and cytokines expression in cats in terminal stage of FIV infection.  相似文献   
78.
Non-surgical embryo transfer is a promising method for improving efficiency in the pork industry and also for biotechnology applications, such as in vitro embryo production, transgenesis and cloning. Several groups have reported successful piglet production using an artificial insemination catheter or flexible catheter designed for this procedure; however, the efficiency of the technique is still low. The critical points that need to be addressed in order to improve this procedure are (1) the embryo deposition site and (2) volume of transfer medium associated with the embryos; however, the latter has not yet been examined systematically. In the present study, we evaluated the effect of the volume of non-surgical embryo transfer medium on the ability of porcine embryos to survive to term by using a recently produced flexible catheter. The catheter consists of a guide and an injector. Blastocysts 200-230 mum in diameter were collected from donor gilts and transferred to recipient gilts. The time required for the completion of embryo transfer using this catheter was 14.6 +/- 3.9 min. The tip of the injector was determined by laparotomy to be located in a uterine horn 20-30 cm anterior from the branching point of the uterus body. We transferred 17.0-17.3 embryos with different volumes of medium (1.6, 3.2 and 10 ml) into each of 5, 4 and 4 recipients, respectively, and pregnancy was confirmed in 4, 3 and 1 of these recipients, respectively. Three recipients in the 1.6 ml group farrowed a total of 19 piglets (4, 5 and 10 piglets, respectively). These results suggest that successful non-surgical embryo transfer is affected by the volume of transfer medium.  相似文献   
79.
Eggs of spiny dogfish Squalus acanthias are an indispensable and effective component of the compound diets currently used for larvae of the Japanese eel Anguilla japonica. However, this fish species, a natural resource, is becoming more scarce, suggesting that suitable diets should be developed using more sustainable components. In the search for appropriate diets without shark eggs, we have designed test diets in which shark eggs were replaced with general feed materials, such as fish protein hydrolysate (FPH), with the notable improvement that the FPH had been pre-digested with integral enzymes from frozen krill. Feeding trials were conducted to assess the effects of the test diets on survival and growth of Japanese eel larvae at early developmental stages. Larvae fed on the test diets were found to be able to survive up to 65 days after hatching, the maximum total length and body depth were 14.1 and 1.5 mm, respectively. Although larvae fed on the test diets still exhibited a low survival rate and poor growth, the FPH-based diets had a nutritional value that promoted substantial larval growth based on the significant difference between the initial and final body sizes. Our results suggest that the development of FPH-based diets not based on shark eggs but rather on general feed ingredients is promising but that there is much room for improvement.  相似文献   
80.
Ten flavonols and three anthocyanins were identified in the fruit peel of melo?n de olor (Sicana odorifera), and their structures were established by spectrometric and spectroscopic (ESI-MS and NMR) techniques. One of the identified flavonols, quercetin 3-O-(6'-O-malonyl)-β-D-glucopyranoside 4'-O-β-D-glucopyranoside, has not been reported before in the plant kingdom. Although quercetin-3-O-α-L-rhamnopyranosyl-(1→6)-β-d-glucopyranoside-4'-O-β-D-glucopyranoside had been reported before in literature and structure elucidation was done by comparison of NMR data with published data, to the best of our knowledge complete 1D and 2D NMR data have not been not delineated so far. Moreover, the antioxidant activity of pure compounds was measured by ABTS assay. It was established that quercetin 3-O-α-L-rhamnopyranosyl-(1→6)-β-D-glucopyranoside, quercetin-3-O-(6'-malonyl)-glucopyranoside, quercetin-3-O-β-D-glucopyranoside, and quercetin-3-O-α-L-rhamnopyranosyl-(1→6)-β-D-glucopyranoside-4'-O-β-D-glucopyranoside contribute significantly to the antioxidant activity exhibited by the fruit peel methanolic extract.  相似文献   
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