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91.
A new furostanol pentaoligoside and spirostanol tetraoligoside were isolated for the first time from yam tubers (Dioscorea pseudojaponica Yamamoto) from Taiwan, together with four known yam saponins, methyl protodioscin, methyl protogracillin, dioscin, and gracillin. Their structures were characterized as 26-O-beta-D-glucopyranosyl-22alpha-methoxyl-(25R)-furost-5-en-3beta,26-diol, 3-O-alpha-L-rhamnopyranosyl-(1-->2)-O-([alpha-L-rhamnopyranosyl-(1-->4)]-O-[alpha-L-rhamnopyranosyl-(1-->4)])-beta-D-glucopyranoside, and (25R)-spirost-5-en-3beta-ol 3-O-alpha-L-rhamnopyranosyl-(1-->2)-O-([alpha-L-rhamnopyranosyl-(1-->4)]-O-[alpha-L-rhamnopyranosyl-(1-->4)])-beta-D-glucopyranoside. The structural identification was performed using LC-MS and 1H and 13C NMR. The methanol extract of yam tubers was fractionated by XAD-2 column chromatography using a methanol/water gradient elution system to yield furostanol and spirostanol glycoside fractions. Preparative high-performance liquid chromatography, employing a C18 column and a mobile phase of methanol/water (69:31, v/v), was used to separate each furostanol glycoside, whereas a mobile phase of methanol/water (79:21, v/v) was used to resolve the individual spirostanol glycosides. The conversions from steroid saponins to diosgenin after acid hydrolysis were around 68 and 90% for furostanol and spirostanol glycosides, respectively.  相似文献   
92.
  1. A small population of approximately 68 bottlenose dolphins, Tursiops truncatus, resident in Doubtful Sound, New Zealand, is subject to physiologically challenging conditions, and is exposed to anthropogenic pressure from tourism.
  2. A voluntary Code of Management incorporating dolphin protection zones (DPZs), in which tour boat access is limited, was established in 2008.
  3. Kernel density estimation (KDE) was used to quantify dolphin habitat use over a 13-year period in order to describe seasonal variation in habitat use and consistency of habitat use over a decadal period, and to provide quantitative estimates of the extent of overlap between DPZs and core areas (50% volume contour) of habitat use.
  4. Habitat use varied seasonally, with the inner fjord area used more frequently in warmer months, and with a shift in use to the outer fjord in colder months. Patterns in habitat use were highly consistent over the 13-year duration of the study.
  5. The spatial overlap between the area of core dolphin habitat and DPZs was low (<18%) overall, and some DPZs were rarely used during colder periods.
  6. Consistency in habitat use through time vindicates spatial management, but low overlap between core habitat and current DPZs suggests that an expansion of the DPZ areas would confer greater protection.
  相似文献   
93.
94.
Sesame seeds (Sesamum indicum L.) are unique because of potent and various physiological activities imparted by their bioactive lignans. This investigation studied the intestinal distribution and excretion of sesaminol in Sprague-Dawley (SD) rats. To investigate the distribution of sesaminol (per oral 220 mg/kg), the changes in concentration of sesaminol and its metabolites were determined in the intestines and plasma within the 24 h period after tube feeding of sesaminol to SD rats. Results show that the epimerization of sesaminol appeared to be catalyzed by acid in the simulated gastric fluids. The major sesaminol epimer was characterized as 2-episesaminol using 2D-NMR. These findings indicate that sesame sesaminol and its epimer are poorly absorbed prior to reaching the rectum and that substantial amounts pass from the small to the large intestine, where they are metabolized by the colonic microflora to tetrahydrofuranoid metabolites. Sesaminol in plasma was largely present as phase II conjugates, and the seven metabolites were detected as the 2-episesaminol, sesaminol-6-catechol, methylated sesaminol-catechol, R,R-hydroxymethylsesaminol-tetrahydrofuran, S,R-hydroxymethylsesaminol-tetrahydrofuran, enterolactone, and enterodiol. Excretions of sesaminol in urine and feces within the 24 h period were equivalent to 0.02 and 9.33% of the amount ingested, respectively.  相似文献   
95.
To understand the implications of atmospheric nitrogen deposition on carbon turnover in peatlands, we conducted a 13C pulse labeling experiment on Calluna vulgaris and Eriophorum vaginatum already receiving long-term (5 years) amendments of 56 kg N ha−1 y−1 as ammonium or nitrate. We examined shoot tissue retention, net ecosystem respiration returns of the 13C pulse, and soil porewater DOC content under the two species. 13C fixation in Eriophorum leaves was enhanced with nitrogen addition and doubled with nitrate supply. This newly fixed C appeared to be relocated below-ground faster with nitrogen fertilization as respiration returns were unaffected by N inputs. By contrast, increases in 13C fixation were not observed in Calluna. Instead, net ecosystem respiration rates over Calluna increased with N fertilization. There was no significant label incorporation into DOC, suggesting a conservative strategy of peatland vegetation regarding allocation of C through root exudation. Greater concentrations of total DOC were identified with nitrate addition in Calluna. Given the long-term nature of the experiment and the high N inputs, the overall impacts of nitrogen amendments on the fate of recently synthesized C in Eriophorum and Calluna in this ombrotrophic peatland were surprisingly more moderate than originally hypothesized. This may be due to N being effectively retained within the bryophyte layer, thus limiting, and delaying the onset of, below-ground effects.  相似文献   
96.
The condensed tannin concentrations and composition and the characterization of the phenolic constituents in the leaves of the forage legume sulla (Hedysarum coronarium), a biennial forage legume found in temperate agricultural regions, were studied. The colorimetric butanol-HCl assay was used for the quantitation of the seasonal condensed tannin concentrations in the leaves of sulla. Fractionation of extracts on Sephadex LH-20 using step elution with aqueous methanol, followed with aqueous acetone or gradient elution with water, aqueous methanol, and aqueous acetone, gave condensed tannin and flavonoid fractions. The chemical characteristics of the purified condensed tannin fractions were studied by acid-catalyzed degradation with benzyl mercaptan and electrospray ionization mass spectrometry (ESI-MS). Thiolysis revealed that epigallocatechin was the major extender unit (15-75%) while gallocatechin was the major terminal unit (50-66%), thus indicating the extractable sulla condensed tannin fraction as the prodelphinidin type. Condensed tannin oligomers to polymers obtained from Sephadex LH-20 gradient fractions ranged between 2.9 and 46 mDP. The homo- and heterogeneous oligomer ions in condensed tannin gradient fractions detected by ESI-MS ranged from 2 to 10 DP and are consistent with the values obtained by thiolysis (2.9-6.9 DP). Lower molecular weight phenolics, including flavonoids and phenolic acids, were characterized by liquid chromatography atmospheric pressure chemical ionization mass spectrometry (LC-APCI/MS) and ESI/MS/MS on a linear ion trap. The flavonoids extracted with aqueous acetone and methanol from sulla leaves and identified included kaempferol, rutin, quercetin-7-O-α-L-rhamnosyl-3-O-glucosylrhamnoside, quercetin-3-O-α-L-rhamnosyl-7-O-glucoside, kaempferol-3-O-β-D-glucoside-dirhamnoside, genistein-7-O-β-D-glucosyl-6″-O-malonate, formononetin-7-O-β-D-glucoside-6″-O-malonate, and afrormosin and the phenolic acid chlorogenic acid.  相似文献   
97.
Maryland-grown soybean lines modified for low lipoxygenase-1 (LOX-1) content and a traditional nonmodified cultivar were analyzed for fatty acid composition, total phenolic content (TPC), isoflavone composition, relative DPPH? scavenging capacity (RDSC), and hydroxyl radical scavenging capacity (HOSC). Soybean lines included black, brown, and yellow soybeans. TPC of all soybean lines ranged from 2.84 to 4.74 mg gallic acid equiv (GAE)/g flour. Total isoflavones were between 2.78 and 8.66 μmol/g flour. RDSC of all lines was between 0.48 and 14.62 μmol Trolox equiv (TE)/g flour, and HOSC ranged from 53.57 to 135.52 μmol TE/g flour. Some modified-LOX genotypes demonstrated antioxidant capacity and/or isoflavone content similar to or higher than those of the nonmodified cultivar (P < 0.05). Black soybeans demonstrated higher TPC and RDSC than most yellow soybean lines, although they did not have higher isoflavone content. The results demonstrate that modification of the LOX trait did not necessarily alter the antioxidant capacity or chemical composition of the experimental soybean lines when compared with a nonmodified cultivar. These soybean lines may be studied further for nutraceutical properties and use in functional foods.  相似文献   
98.
The issue of inherited disorders in pedigree dogs is not a recent phenomenon and reports of suspected genetic defects associated with breeding practices date back to Charles Darwin's time. In recent years, much information on the array of inherited defects has been assimilated and the true extent of the problem has come to light. Historically, the direction of research funding in the field of canine genetic disease has been largely influenced by the potential transferability of findings to human medicine, economic benefit and importance of dogs for working purposes. More recently, the argument for a more canine welfare-orientated approach has been made, targeting research efforts at the alleviation of the most suffering in the greatest number of animals. A method of welfare risk assessment was initially developed as a means of objectively comparing, and thus setting priorities for, different welfare problems. The method has been applied to inherited disorders in pedigree dogs to investigate which disorders have the greatest welfare impact and which breeds are most affected. Work in this field has identified 396 inherited disorders in the top 50 most popular breeds in the UK. This article discusses how the results of welfare risk assessment for inherited disorders can be used to develop strategies for improving the health and welfare of dogs in the long term. A new risk assessment criterion, the Breed-Disorder Welfare Impact Score (BDWIS), which takes into account the proportion of life affected by a disorder, is introduced. A set of health and welfare goals is proposed and strategies for achieving these goals are highlighted, along with potential rate-determining factors at each step.  相似文献   
99.
The unique open reading frame 11 (LORF11) of Marek's disease virus (MDV) is present in all three serotypes of MDV and is located in the unique long region of the MDV genome. In the serotype 1 Md5 genome, LORF11 comprises 2711 nucleotides and encodes a predicted protein of 903 amino acids. In order to study the biological function of LORF11 we deleted it from the MDV cosmid A6 by using the RecA-assisted restriction endonuclease cleavage method. The recombinant cosmid, A6DeltaLORF11, was transfected into duck embryo fibroblasts (DEF) in conjunction with parental SN5, P89, SN16, and B40 cosmid clones. Recombinant rMd5DeltaLORF11 plaques were evident at 12-13 days after transfection. Polymerase chain reaction amplification of DEF cells infected with rMd5DeltaLORF11 viruses confirmed the deletion of a 2.57-kb fragment resulting in a 296-bp fragment. Three rMd5DeltaLORF11 mutants were generated and their biological functions were studied in vitro and in vivo. In vitro growth characteristics of rMd5DeltaLORF11 viruses were similar to those of parental rMd5, indicating that LORF11 is not essential for replication in vitro. In vivo studies of rMd5DeltaLORF11 mutants showed that they were impaired in viral replication in the lymphoid organs and had 100x lower viremia than chickens infected with the parental rMd5 virus. Furthermore, rMd5-infected chickens horizontally transmitted the virus to contact controls whereas no horizontal transmission occurred in rMd5DeltaLORF11-infected chickens. Three independent deletion mutants were tested and showed the same phenotypes, so it is unlikely that the observed phenotype is because of any random mutation in the genome. Therefore the LORF11 gene of MDV is essential for normal virus replication in chickens and deletion of LORF11 renders an attenuated virus.  相似文献   
100.
BACKGROUND: The western barred bandicoot (Perameles bougainville) is an Australian marsupial species now considered endangered as a consequence of habitat destruction and predation. A recently discovered papillomatosis syndrome is hindering efforts to repopulate this species. Hematology reference intervals have been lacking for P bougainville, preventing optimal interpretation of hematology results from wart-affected and clinically normal animals. OBJECTIVES: The purpose of this study was to establish hematology reference values and describe morphologic characteristics of blood cells of healthy western barred bandicoots. METHODS: Fifty-nine whole blood samples were collected by jugular venipuncture into EDTA from 47 clinically healthy captive western barred bandicoots at 3 locations on the Western Australian mainland. A CBC was performed using an ADVIA-120 analyzer. Data were compared on the basis of geographic location, sex, age, and lactation status, and reference intervals were calculated. Blood cell morphology was evaluated using light microscopy, and transmission and scanning electron microscopy. RESULTS: Significant differences were found based on sex (RBC indices, fibrinogen), age (% polychromatophilic RBCs), and geographic location (RBC, neutrophil, and lymphocyte counts, MCHC, % polychromatophilic RBCs, fibrinogen). Combined reference intervals were calculated for hemoglobin concentration (122-165 g/L), HCT (0.36-0.49 L/L), and total WBC (2.9-14.9 x 10(9)/L), monocyte (0-0.6 x 10(9)/L), eosinophil (0-0.9 x 10(9)/L), and total plasma protein (47-63 g/L) concentrations. Leukocyte, erythrocyte, and platelet morphology were similar to those of other marsupial peramelid species. Nuclei in neutrophils, monocytes, and eosinophils occasionally had an annular configuration. CONCLUSIONS: Reference intervals and blood cell morphology obtained in this study will be useful for the evaluation of laboratory data from ill animals and assist with population health monitoring of western barred bandicoots.  相似文献   
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