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71.
Ye Ji Park Si Hyun Seong Min Sun Kim Sang Wan Seo Mee Ree Kim Hyun Sik Kim 《Plant methods》2017,13(1):108
Background
Plant extracts contain a huge variety of pharmacologically active substances. Conventionally, various chromatographic methods must be applied several times to purify functional compounds to measure their functional activity. However, conventional purification methods are time-consuming and expensive due to the laborious purification process. Recently, a high-throughput discovery method that replaces such time-consuming purification processes was introduced; this method uses 15 T ultra-high-resolution Fourier transform ion cyclotron resonance mass spectrometry (15 T FT-ICR MS) and a high-throughput screening method. This 15 T FT-ICR MS provides unparalleled resolution and sub-ppm accuracy in mass measurements, while simultaneously detecting multiple compounds without separation. The high-throughput, simultaneous multi-component discovery method known as Scaling of Correlations between Activity and Mass Profiles (SCAMP) was used to detect functional compounds in a plant extract. We validated the performance of SCAMP using 33 fractions from antioxidant-rich mulberry ethyl acetate extract and known standard antioxidants.Results
The mulberry fruit was first separated into 33 fractions by LC and analyzed using high-resolution mass spectrometry. The antioxidative strength of the 33 fractions and standard antioxidants was measured. To validate the efficiency of this antioxidant discovery method, correlations between the antioxidation activity profile and changes in mass intensity of components within the 33 fractions were calculated to provide relative scores for the antioxidant candidate list. Enrichment curves and area under the curve (AUC) values were then calculated to compare the performance of the methods. Using this improved scoring method, five strong antioxidants, chlorogenic acid (14.2 ng), dihydoxy quercetin (46.2 ng), rutin (154.0 ng), quercetin (71.7 ng) and luteolin (3.5 ng) in 2 kg mulberry fruit, were found within the top 20 candidates.Conclusions
We calculated AUCs in order to compare scoring methods quantitatively. Scoring systems were compared and calculated AUCs, where the AUCs for new scoring systems (0.98 and 0.99) were higher than the previously used correlation coefficient (AUC = 0.89). Using the new scoring algorithms, we successfully enriched thirteen unknown strong antioxidant candidates in addition to known antioxidants, methyl syringin and naringenin (3.5 ng) in mulberry extract. Targeted purification of these unknown candidates will significantly reduce purification time and labor.72.
John F Mee 《Veterinary Clinics of North America: Food Animal Practice》2004,20(3):521-546
Managing the dairy cow at calving, unlike artificial insemination or transrectal ultrasonography, is often perceived as an unskilled task, not requiring specialist training. This article presents the argument for the financial and welfare costs associated with poor periparturient management, and how to address them by veterinarian-led education and upskilling of herd personnel. Successful management of the dairy cow at calving will result in the birth of a healthy calf and a smooth transition of the cow into the milking string with minimal calving problems and their sequelae. The tenets of good calving management are predicting accurately when calving is due, moving cows to the maternity unit on time, discrete calving supervision, knowing when and how to intervene, and ensuring the calf is vigorous and fed colostrum and the cow is healthy postpartum. 相似文献
73.
Despite advances in dairy herd health and productivity, perinatal calf mortality rates are still unacceptably high on many dairy farms. The key features of successful newborn dairy calf management are ensuring heifers and cows are moved in time to calve in suitable maternity housing, discreet calving supervision and appropriate timing of any necessary calving assistance, immediate parturient evaluation of at-risk newborn calves followed by aggressive resuscitation, strategic navel antisepsis, early detection (and treatment) of perinatal problems, and prompt movement of the newborn calf to hygienic calf housing. Veterinarian-led producer implementation of active management of calving and newborn calf care can improve perinatal welfare and health. 相似文献
74.
Patterns of fish species distributions replicated across three parallel rivers suggest biotic zonation in response to a longitudinal temperature gradient
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Environmental gradients determine the distributions of individual species, which, in turn, shape patterns of species assemblage across those gradients. We used species distribution models to study the assemblage of fish species along the three mainstem rivers in the South Saskatchewan River Basin (SSRB) in Alberta, which flow in parallel across an 800‐km longitudinal span and down 1400 m from the Rocky Mountains to the Great Plains of North America. We estimated the similarity of species assemblages along each river to identify general patterns of species assemblage associated with temperature and five other physiochemical variables. Mean July water temperature, which ranged from <11°C at high elevation to >21°C at low elevation, was strongly associated with the presence–absence of most species in the SSRB. We found that high turnover occurred at two locations along the longitudinal gradient: where mean July water temperature was approximately 15°C and where mean July water temperature was approximately 19 or 20°C. There was also an increase in species richness at lower elevations where water temperatures were higher. Models incorporating forecasted changes in water temperature with climate change will likely provide accurate predictions of changes in the diversity and distribution of riverine fish communities across topographically heterogeneous landscapes. 相似文献
75.
Michael D. Swartz Qianxing Mo Mary E. Murphy Joanne R. Lupton Nancy D. Turner Mee Young Hong Marina Vannucci 《Journal of Agricultural, Biological & Environmental Statistics》2008,13(4):407-423
In this article we focus on clustering techniques recently proposed for high-dimensional data that incorporate variable selection
and extend them to the modeling of data with a known substructure, such as the structure imposed by an experimental design.
Our method essentially approximates the within-group covariance by facilitating clustering without disrupting the groups defined
by the experimenter. The method we adopt simultaneously determines which expression patterns are important, and which genes
contribute to such patterns. We evaluate performance on simulated data and on microarray data from a colon carcinogenesis
study. Selected genes are biologically consistent with current research and provide strong biological validation of the cluster
configuration identified by the method. 相似文献
76.
Hyun Ah Jung Md. Nurul Islam Chan Mee Lee Hyong Oh Jeong Hae Young Chung Hee Chul Woo Jae Sue Choi 《Fisheries Science》2012,78(6):1321-1329
In the present study, we investigated the antidiabetic potential of fucoxanthin via the inhibition of rat lens aldose reductase (RLAR), human recombinant aldose reductase (HRAR), advanced glycation end-product (AGE) formation, protein tyrosine phosphatase 1B (PTP1B), and α-glucosidase. Fucoxanthin displayed potent inhibitory activity against AGE formation and HRAR and RLAR activity. In addition, fucoxanthin showed potent inhibitory activity against PTP1B. However, it did not show α-glucosidase inhibitory activity below 200 μM. In addition, our kinetic study revealed that fucoxanthin competitively inhibited RLAR, while it showed mixed-type inhibition against PTP1B. In order to confirm enzyme inhibition, we predicted the 3D structure of PTP1B using Autodock 4.0 to simulate the binding of fucoxanthin. Docking simulation results demonstrated that three residues of PTP1B (Phe30, Phe52, and Gly183) interact with the two hydroxyl groups of fucoxanthin. In addition, the binding energy was negative (?7.66 kcal/mol), indicating that the three hydrogen bonds may stabilize the open form of the enzyme and potentiate tighter binding to the active site of PTP1B, resulting in more effective PTP1B inhibition. The results of the present study therefore clearly demonstrate the promising potential of fucoxanthin as a therapeutic intervention for the management of diabetes as well as diabetes-associated complications, which could be explored further. 相似文献
77.
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79.
A 4‐year‐old female Suri alpaca was presented for evaluation of acute onset weakness, lethargy, and recent development of opacities in both eyes. On ophthalmic examination, bilaterally symmetrical corneal opacities were noted along the interpalpebral fissures with a few corneal blood vessels intermingled. A presumed diagnosis of calcific band keratopathy was made based on location and appearance. The patient was euthanized a short while after diagnosis due to reasons unrelated to the eyes and histologic examination of the corneas revealed subepithelial calcium and vascularization, consistent with calcific band keratopathy. This case report is the first to document this ocular condition in an alpaca. 相似文献
80.
Hwang WS Roh SI Lee BC Kang SK Kwon DK Kim S Kim SJ Park SW Kwon HS Lee CK Lee JB Kim JM Ahn C Paek SH Chang SS Koo JJ Yoon HS Hwang JH Hwang YY Park YS Oh SK Kim HS Park JH Moon SY Schatten G 《Science (New York, N.Y.)》2005,308(5729):1777-1783
Patient-specific, immune-matched human embryonic stem cells (hESCs) are anticipated to be of great biomedical importance for studies of disease and development and to advance clinical deliberations regarding stem cell transplantation. Eleven hESC lines were established by somatic cell nuclear transfer (SCNT) of skin cells from patients with disease or injury into donated oocytes. These lines, nuclear transfer (NT)-hESCs, grown on human feeders from the same NT donor or from genetically unrelated individuals, were established at high rates, regardless of NT donor sex or age. NT-hESCs were pluripotent, chromosomally normal, and matched the NT patient's DNA. The major histocompatibility complex identity of each NT-hESC when compared to the patient's own showed immunological compatibility, which is important for eventual transplantation. With the generation of these NT-hESCs, evaluations of genetic and epigenetic stability can be made. Additional work remains to be done regarding the development of reliable directed differentiation and the elimination of remaining animal components. Before clinical use of these cells can occur, preclinical evidence is required to prove that transplantation of differentiated NT-hESCs can be safe, effective, and tolerated. 相似文献