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111.
Inhibitory effects of nine dibenzylbutyrolactone lignans on a human matrix metalloproteinase, matrilysin, were examined. All of the lignans examined inhibited matrilysin with the IC(50) values ranging from 50 to >280 microM. Matairesinol, which has the basic structure of the other lignans, showed the weakest inhibition. Lignans with methylenedioxy ring(s) or a hydroxyl group at the C5-position inhibited matrilysin more strongly than matairesinol. 5-Hydroxypluviatolide, which has both a methylenedioxy ring and a hydroxyl group at the C5-position, was the most potent inhibitor (IC(50) = 50 microM), suggesting that the introduction of these two elements might enhance synergistically the inhibitory activity of lignans. 5-Hydroxypluviatolide inhibited matrilysin in a competitive manner, and its inhibitory effect was greatly suppressed by the presence of another competitive inhibitor, dimethyl sulfoxide. The precursors of matairesinol, coniferyl alcohol and secoisolariciresinol, had no inhibitory activity, indicating that the dibenzylbutyrolactone structure is essential for the inhibition. It has been shown that lignans have the potential to inhibit matrilysin, and the knowledge of their structure-activity relationship might be beneficial to developing selective inhibitors for matrix metalloproteinases.  相似文献   
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A rare dysraphic caudal spinal anomaly, or caudal agenesis, comprising a tethered spinal cord, was found in a tailless Holstein calf that presented ataxia and paresis with analgesia of the hind limbs. The gently and slimly tapered conus medullaris was poorly formed between S2 and S3 which indicated that it was lying more caudally. The caudal end of the filum terminale adhered to the inner periosteum of the vertebral arch at S4, which is compatible with tethering of the spinal cord. The dysraphic changes from the secondary neurulation error and the longitudinal deranged cord morphology that may have been caused by the caudad traction due to tethering were confirmed. This represents the first bovine case with definitive morphological confirmation.  相似文献   
115.
Psittacid herpesvirus type 1 (PsHV-1) was isolated from a captive galah (Eolophus roseicapillus) in Japan that was suspected of having Pacheco's disease (PD), an acute fatal disease in psittacine birds. PsHV-1 has been classified into four genotypes based on the UL16 gene sequence. In the present study, we investigated the genetic and pathogenic characteristics of the isolated virus, FOY-1, compared with a reference strain, RSL-1. The FOY-1 strain was classified into PsHV-1 genotype 2. The FOY-1 strain was found to be less pathogenic to budgerigars than RSL-1, which was classified as genotype 4 in an in vivo study. This is the first report regarding the classification of originally isolated PsHV-1 in Japan and its characterization by animal infection experiment.  相似文献   
116.
Dairy farm agricultural income should increase when sexed semen is used instead of unsexed semen. This study simulated three scenarios: using unsexed semen (N), using X sperm of Holstein and unsexed semen of Japanese Black (H), and using X sperm of Holstein and Y sperm of Japanese Black (HJ). Two management scenarios were considered: conventional management (CONV); and the use of Japanese Black semen with surplus cows to produce F1s where sufficient replacement female Holstein calves were obtained for maintenance (MAINT). In CONV, the agricultural incomes of H and HJ were 610 000–2 400 000 yen higher than that of N. The agricultural income increased when the difference in the prices between Holstein males and average F1 male/female calves was 34 000–50 000 yen, that between Holstein male and female calves was 80 000–110 000 yen, and that between F1 male and female calves was 50 000–90 000 yen. Therefore, the agricultural income can be increased by using sexed semen to select calves of a more valued breed and sex.  相似文献   
117.
To investigate time‐dependent change in the bovine whey proteome during the early lactation period, a two‐dimensional gel‐based approach was used in this study. Milk samples were collected from five healthy Friesian‐Holstein dairy cows up to 10 days postpartum. Spot patterns of whey proteins varied drastically from immediately after parturition to 48 h, but no significant changes occurred thereafter. Protein identification by mass spectrometry revealed that the ratios of caseins and immunoglobulins drastically decreased during 48 h postpartum, while those of lower molecular mass proteins such as α‐lactalbumin and β‐lactoglobulin increased. More than 100 spots were detected, being much more abundant in colostral whey than in mature milk whey. Of a total of 25 proteins identified, four, viz. zinc‐α‐2‐glycoprotein, vitamin D‐binding protein, immunoglobulin G2 chain C and β2‐microglobulin, were detectable only in colostrum. Our results indicate that most of the minor whey proteins in colostrum relate to the passive immunity of newborn calves, but some of them play significant roles in nutritional supplementation of the neonate. The characteristics of whey proteins in transition imply that enhancement of innate immunity becomes more important than protection of the neonate against pathogens via passive immunity after 48 h postpartum.  相似文献   
118.
Since cucumber plants are mostly discarded as large waste after crop harvesting, allelopathy of cucumber plants was investigated for possible weed management options and utilization of the waste. Two potent growth inhibitory substances were isolated from an aqueous methanol extract of cucumber (Cucumis sativus L. cv. Phung Tuong) plants. These substances were determined as 9-hydroxy-4,7-megastigmadien-9-one (HMO) and (6S,7E,9S)-6,9,10-trihydroxy-4,7-megastigmadien-3-one (THMO) by the analysis of MS, 1H NMR spectra and optical rotation. HMO inhibited the growth of cress (Lepidium sativum L.) and Echinochloa crus-galli (L.) Beauv seedlings at concentrations greater than 0.3 and 1 μM, respectively. THMO inhibited the growth of cress and E. crus-galli seedlings at concentrations greater than 1 and 3 μM, respectively. The concentrations required for 50% growth inhibition on roots and shoots of cress and E. crus-galli were 2.4–29.3 μM for HMO and 8.1–52.2 μM for THMO. The endogenous levels of HMO and THMO in cucumber plants were 31.8 and 43.5 μg g−1 dry weight, respectively. These results suggest that HMO and THMO may be the causal factors for the growth inhibitory effect of cucumber plants. Therefore, cucumber plants may be potentially useful for weed management options in an agricultural setting, such as a cover crop and soil admixture, which should be investigated further in the field.  相似文献   
119.
Twelve polar cardenolide monoglycosides, 1, 2, 4?C13, and oleagenin (3) were isolated from the methanol extract of stems and twigs of Nerium oleander. Among these, oleagenin (3) and cardenolide monoglycosides named cardenolide B-1 (1) and cardenolide B-2 (2) were isolated from natural sources for the first time. The in vitro antiinflammatory activity of compounds 1?C13 was examined on the basis of inhibitory activity against the induction of the intercellular adhesion molecule-1 (ICAM-1). Compounds 4?C7 were active at an IC50 value of less than 0.4 ??M. The cytotoxic activity of compounds 1?C13 was evaluated against three human cell lines: normal human fibroblast cells (WI-38), malignant tumor cells derived from WI-38 (VA-13), and human liver tumor cells (HepG2). Compounds 4, 6, and 7 were active toward these three cell lines at IC50 values of less than 0.7 ??M, and compounds 5 and 8 were active toward the cell lines at IC50 values of less than 1.5 ??M. The multidrug resistance (MDR) cancer-reversal activity of compounds 1?C13 was evaluated on the basis of the amount of calcein accumulated in MDR human ovarian cancer 2780AD cells in the presence of each compound. Compound 1 and 12 showed significant effects on calcein accumulation.  相似文献   
120.
Acacia mangium is a fast-growing tree widely planted in tropical countries because of its rapid growth, high wood density, high fiber quality, and good adaptability. Despite its importance as a fiber source in the pulp and paper industry, a large-scale analysis of expressed sequence tags (ESTs) has not been performed in A. mangium. In this study, we sequenced 10 752 clones of a normalized complementary DNA (cDNA) library prepared from A. mangium developing secondary xylem and shoot, and obtained a total of 8963 ESTs. The ESTs were assembled into 6220 unigenes comprising 1614 contigs and 4606 singletons. The unigene set was then subjected to various bioinformatic analyses. BlastN searches of the unigene set against the Gene Index Databases of soybean, Medicago truncatula, Lotus japonicus, grape, poplar, spruce, and pine demonstrated that the largest number of unigenes shared homologies with the soybean Gene Indices. BlastX searches against the TAIR9 peptide database enabled us to annotate the unigenes. Based on the annotation, we discussed whether the unigenes involved in the cell cycle, cell growth, shoot apical meristem development, and cell wall biosynthesis were present. This new genomic resource will accelerate the functional genomics of wood formation and molecular breeding to improve the wood properties of A. mangium.  相似文献   
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