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121.
To determine if matrix metalloproteinase (MMP)-28 mediates cardiac aging, wild-type (WT) and MMP-28-/- young (7 ± 1 months, n = 9 each) and old (20 ± 2 months, n = 7 each) female mice were evaluated. MMP-28 expression in the left ventricle (LV) increased 42% in old WT mice compared to young controls (p < 0.05). By Doppler echocardiography, LV function declined at 20 ± 2 months of age for both groups. However, dobutamine stress responses were similar, indicating that cardiac reserve was maintained. Plasma proteomic profiling revealed that macrophage inflammatory protein (MIP)-1 α, MIP-1β and MMP-9 plasma levels did not change in WT old mice but were significantly elevated in MMP-28-/- old mice (all p < 0.05), suggestive of a higher inflammatory status when MMP-28 is deleted. RT2-PCR gene array and immunoblotting analyses demonstrated that MIP-1α and MMP-9 gene and protein levels in the LV were also higher in MMP-28-/- old mice (all p < 0.05). Macrophage numbers in the LV increased similarly in WT and MMP-28-/- old mice, compared to respective young controls (both p < 0.05). Collagen content was not different among the WT and MMP-28-/- young and old mice. In conclusion, LV inflammation increases with age, and MMP-28 deletion further elevates inflammation and extracellular matrix responses, without altering macrophage numbers or collagen content. 相似文献
122.
Lindsey EA Worthington RJ Alcaraz C Melander C 《Organic & biomolecular chemistry》2012,10(13):2552-2561
An efficient synthetic route to a series of substituted 2-aminopyrimidine (2-AP) derivatives has been developed. Subsequent biofilm screening has allowed comparison between the biological activity of these new derivatives and that of the 2-aminoimidazole class of anti-biofilm compounds. Several derivatives displayed the ability to modulate bacterial biofilm formation, exhibiting greater activity against Gram-positive strains than Gram-negative strains. Additionally some 2-aminopyrmidines were able to suppress MRSA resistance to conventional antibiotics. 相似文献
123.
All solvable Lie algebras with Heisenberg nilradical have already been classified. We extend this result to a classification of solvable Leibniz algebras with Heisenberg nilradical. As an example, we show the complete classification of all real or complex Leibniz algebras whose nilradical is the 3-dimensional Heisenberg algebra. 相似文献
124.
Teo Tang Lin Lippa Katrice A. Mackay Lindsey Yong Sharon Liu Qinde Camara Johanna E. Delatour Vincent Lee Tong Kooi Lalere Béatrice O’ Connor Gavin Henrion André Kato Megumi Numata Masahiko Kwon Ha-Jeong Jeong Ji-Seon Xu Bei Song Dewei Nammoonnoy Jintana Wollinger Wagner 《Analytical and bioanalytical chemistry》2019,411(28):7341-7355
Analytical and Bioanalytical Chemistry - Over two decades, the Organic Analysis Working Group (OAWG) of the Consultative Committee for Amount of Substance: Metrology in Chemistry and Biology (CCQM)... 相似文献
125.
Thomas B. R. Robertson Lysbeth H. Antonides Nicolas Gilbert Dr. Sophie L. Benjamin Dr. Stuart K. Langley Dr. Lindsey J. Munro Dr. Oliver B. Sutcliffe Dr. Ryan E. Mewis 《ChemistryOpen》2019,8(12):1375-1382
Fentanyl, also known as ‘jackpot’, is a synthetic opiate that is 50–100 times more potent than morphine. Clandestine laboratories produce analogues of fentanyl, known as fentalogues to circumvent legislation regarding its production. Three pyridyl fentalogues were synthesized and then hyperpolarized by signal amplification by reversible exchange (SABRE) to appraise the forensic potential of the technique. A maximum enhancement of -168-fold at 1.4 T was recorded for the ortho pyridyl 1H nuclei. Studies of the activation parameters for the three fentalogues revealed that the ratio of ligand loss trans to hydride and hydride loss in the complex [Ir(IMes)(L)3(H)2]+ (IMes=1,3-bis(2,4,6-trimethylphenyl)imidazole-2-ylidene) ranged from 0.52 to 1.83. The fentalogue possessing the ratio closest to unity produced the largest enhancement subsequent to performing SABRE at earth's magnetic field. It was possible to hyperpolarize a pyridyl fentalogue selectively from a matrix that consisted largely of heroin (97 : 3 heroin:fentalogue) to validate the use of SABRE as a forensic tool. 相似文献
126.
A phosphoric acid derivative has been shown to promote the addition between an imine and several aldehyde substrates through an enamine intermediate to give cross-aldol condensation products. The reaction scope and preliminary mechanistic investigations will be presented. 相似文献
127.
Kuo Chu Hwang David Mauzerall Richard W. Wagner Jonathan S. Lindsey 《Photochemistry and photobiology》1994,59(2):145-151
A one flask synthesis of cis -substituted amphipathic porphyrins is reported. These porphyrins were used to study electrostatic effects on photoinduced electron transfer across the lipid bilayer-water interface. A neutral porphyrin undergoes only dynamic interfacial electron transfer reactions irrespective of charge of the acceptor, although ionic strength effects indicate a negative charge on the porphyrin donor species. A dianionic porphyrin forms an interfacial static complex with a dicationic electron acceptor, methyl viologen, at low ionic strength. The electron transfer rate within the complex is slow, 105 ∼ 106 s-1 , which is attributed to a near orthogonal orientation between the donor and the acceptor ∼ orbitals. 相似文献
128.
Genetic variation of human senses within the normal range probably exists but usually cannot be investigated in detail for lack of appropriate methods. The study of subtle perceptual differences in red-green colour vision is feasible since both photopigment genotypes and psychophysical phenotypes can be assessed by sophisticated techniques. Red-green colour vision in humans is mediated by two different visual pigments: red (long-wavelength sensitive) and green (middle-wavelength sensitive). The apoproteins of these highly homologous photopigments are encoded by genes on the X chromosome. Colour matches of males with normal colour vision fall into two main groups that appear to be transmitted by X-linked inheritance. This difference in colour matching is likely to reflect small variations in the absorption maxima of visual pigments, suggesting the presence of two common variants of the red and/or green visual pigments that differ in spectral positioning. We report that a common single amino-acid polymorphism (62% Ser, 38% Ala) at residue 180 of the X-linked red visual pigment explains the finding of two major groups in the distribution of colour matching among males with normal colour vision. 相似文献
129.
α-Haloketones and -dibromides are converted to the corresponding ketones and alkenes respectively with nickel boride generated from sodium borohydride and nickel chloride. 相似文献
130.
T. Alexopoulos C. Allen E. W. Anderson V. Balamurali S. Banerjee P. D. Beery P. Bhat J. M. Bishop N. N. Biswas A. Bujak D. D. Carmony T. Carter P. Cole Y. Choi R. DeBonte V. DeCarlo A. R. Erwin C. Findeisen A. T. Goshaw L. J. Gutay A. S. Hirsch C. Hojvat J. R. Jennings V. P. Kenney C. S. Lindsey C. Loomis J. M. LoSecco T. McMahon A. P. McManus N. Morgan K. Nelson S. H. Oh N. T. Porile A. Rimai D. Reeves W. J. Robertson R. P. Scharenberg B. C. Stringfellow S. R. Stampke M. Thompson F. Turkot W. D. Walker C. H. Wang J. Warchol D. K. Wesson Y. Zhan 《Zeitschrift fur Physik C Particles and Fields》1995,67(3):411-416
Fermilab experiment E735 located at the CO intersection region of the $\sqrt s = 1.8$ TeV $p\bar p$ collider analysed over 900 Φ→K + K ? events. Measured were the transverse momentum spectrum, the correlation between the average transverse momentum <pt> and the charged particle multiphcityN c , as well as the probability of Φ production per charged track,N Φ /N c , versusN c . We have also made an estinate of the total inclusive cross section for Φ mesons, $\sigma (p\bar p \to \phi X) = 7.3 \pm 2.2 mb$ . 相似文献