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P S Hayes L M Graves G W Ajello B Swaminathan R E Weaver J D Wenger A Schuchat C V Broome 《Applied and environmental microbiology》1991,57(8):2109-2113
We compared the cold enrichment (CE) and U.S. Department of Agriculture (USDA) methods for isolating Listeria monocytogenes by examining 402 food samples. The food samples were collected from refrigerators of listeriosis patients as part of a multistate active surveillance project to determine the role of foods in sporadic listeriosis in the United States. L. monocytogenes was isolated from 51 food samples (13%). The USDA method was significantly better (P less than 0.001) than the CE method. The isolation efficiencies of the USDA and CE methods were 96 and 59%, respectively. Quantitation of L. monocytogenes in the food samples revealed that many food samples containing less than 0.3 CFU/g were negative as determined by the CE method but positive as determined by the USDA method. 相似文献
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George Flouret Zdzislaw S. Arnold Tadeusz Majewski Nikolaos H. Petousis Kevin Mahan Firdous Farooqui Katherine A. Blum Danuta Konopinska Swaminathan Natarajan David Crich 《Journal of peptide science》1995,1(2):89-108
We report 104 analogues of the potent antiovulatory antagonist of LHRH, N-Ac-D -Nal-D -Cpa-D -Pal-Ser-Lys(Nic)-D -Lys(Nic)-Leu-Ilys-Pro-D -Ala-NH2, Antide. We replaced the Nic group in Antide with other acyl substituents to modulate size, hydrophilicity or basicity of the molecule, we also replaced th Lys residues with shorter basic amino acids, and made cyclic 5/6 analogues as well as position 5 or 6 dimers. We substituted Ilys8 with other alkyl groups and acyl derivatives. When injected in 0.1% DMSO in water in a typical antiovulatory (AO) assay, Antide gives six rats ovulating out of eight (6/8) at 2 μg, 4/8 at 4 μg, and the histamine release assay (HRA), ED50 is >300 μg/ml; [Lys(N-Isobutyl)8]Antide gave 2/8 at 2 μg/rat; [Lys (8-Qis)5]Antide gave 1/8 at 1 μg, and 0/8 at 2 μg, and in the HRA ED50, 22 μg/ml; [D -Lys(8-Qis)6]Antide gave 4/8 at 1 μg and 0/8 at 2 μg, and in the HRA, ED50 was 27 μg/ml; [Lys(8-Qic)8] gave 5/8 at 1 μg, 1/8 at 2 μg/ [Lys(2-Pyc)5]Antide gave 5/8 at 1 μg and 0/8 at 2 μg, and in the HRA ED50 was 116 μg/ml; [D -Lys (2-Pyc)6]Antide gave 3/8 at 1 μg, and in the HRA, ED50 was 100 - >300 μg/ml; [Lys(2-Pyc)5,D -Lys(2-Pyc)6]Antide gave 2/8 at 1 μg. The substitutions of the Nic groups of Antide at Lys5 or D -Lys6 with 8-Qis or with 2-Pyc groups seem to give highly potent antiovulatory antagonists of LHRH and constitute significant new leads to generate potent antiovulatory compounds endowed with moderate or low histamine release. 相似文献
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Nika Rajabian Debanik Choudhury Izuagie Ikhapoh Shilpashree Saha Aishwarya S. Kalyankar Pihu Mehrotra Aref Shahini Kendall Breed Stelios T. Andreadis 《Aging cell》2023,22(3):e13764
Cellular senescence leads to the depletion of myogenic progenitors and decreased regenerative capacity. We show that the small molecule 2,6-disubstituted purine, reversine, can improve some well-known hallmarks of cellular aging in senescent myoblast cells. Reversine reactivated autophagy and insulin signaling pathway via upregulation of Adenosine Monophosphate-activated protein kinase (AMPK) and Akt2, restoring insulin sensitivity and glucose uptake in senescent cells. Reversine also restored the loss of connectivity of glycolysis to the TCA cycle, thus restoring dysfunctional mitochondria and the impaired myogenic differentiation potential of senescent myoblasts. Altogether, our data suggest that cellular senescence can be reversed by treatment with a single small molecule without employing genetic reprogramming technologies. 相似文献
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Jothiramshekar Saranya Benjamin Jenifer Joseph Krishnasamy Rani George Suja Swaminathan Rajalakshmi Parida Ajay 《Physiology and Molecular Biology of Plants》2020,26(1):163-172
Physiology and Molecular Biology of Plants - Salinization of soil is a prime abiotic stress that limits agriculture productivity worldwide. To Study the mechanisms that halophytes take up to... 相似文献
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