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871.
Srdjan M. Vlajkovic Kyu-Hyun Lee Ann Chi Yan Wong Cindy X. Guo Rita Gupta Gary D. Housley Peter R. Thorne 《Purinergic signalling》2010,6(2):273-281
Hearing loss from noise exposure is a leading occupational disease, with up to 5% of the population at risk world-wide. Here,
we present a novel purine-based pharmacological intervention that can ameliorate noise-induced cochlear injury. Wistar rats
were exposed to narrow-band noise (8–12 kHz, 110 dB SPL, 2–24 h) to induce cochlear damage and permanent hearing loss. The
selective adenosine A1 receptor agonist, adenosine amine congener (ADAC), was administered intraperitoneally (100 μg/kg/day) at time intervals after
noise exposure. Hearing thresholds were assessed using auditory brainstem responses and the hair cell loss was evaluated by
quantitative histology. Free radical damage in the organ of Corti was assessed using nitrotyrosine immunohistochemistry. The
treatment with ADAC after noise exposure led to a significantly greater recovery of hearing thresholds compared with controls.
These results were upheld by increased survival of sensory hair cells and reduced nitrotyrosine immunoreactivity in ADAC-treated
cochlea. We propose that ADAC could be a valuable treatment for noise-induced cochlear injury in instances of both acute and
extended noise exposures. 相似文献
872.
Ross N. Cuthbert Ryan J. Wasserman Tatenda Dalu Horst Kaiser Olaf L. F. Weyl Jaimie T. A. Dick Arnaud Sentis Michael W. McCoy Mhairi E. Alexander 《Ecology and evolution》2020,10(12):5946-5962
- Predation is a pervasive force that structures food webs and directly influences ecosystem functioning. The relative body sizes of predators and prey may be an important determinant of interaction strengths. However, studies quantifying the combined influence of intra‐ and interspecific variation in predator–prey body size ratios are lacking.
- We use a comparative functional response approach to examine interaction strengths between three size classes of invasive bluegill and largemouth bass toward three scaled size classes of their tilapia prey. We then quantify the influence of intra‐ and interspecific predator–prey body mass ratios on the scaling of attack rates and handling times.
- Type II functional responses were displayed by both predators across all predator and prey size classes. Largemouth bass consumed more than bluegill at small and intermediate predator size classes, while large predators of both species were more similar. Small prey were most vulnerable overall; however, differential attack rates among prey were emergent across predator sizes. For both bluegill and largemouth bass, small predators exhibited higher attack rates toward small and intermediate prey sizes, while larger predators exhibited greater attack rates toward large prey. Conversely, handling times increased with prey size, with small bluegill exhibiting particularly low feeding rates toward medium–large prey types. Attack rates for both predators peaked unimodally at intermediate predator–prey body mass ratios, while handling times generally shortened across increasing body mass ratios.
- We thus demonstrate effects of body size ratios on predator–prey interaction strengths between key fish species, with attack rates and handling times dependent on the relative sizes of predator–prey participants.
- Considerations for intra‐ and interspecific body size ratio effects are critical for predicting the strengths of interactions within ecosystems and may drive differential ecological impacts among invasive species as size ratios shift.
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Samuel Terrettaz Sylvain Follonier Solomzi Makohliso Horst Vogel 《Journal of structural biology》2009,168(1):177
Tethered lipid bilayers, containing a transmembrane synthetic ligand-gated ion channel (SLIC), have been formed on gold surfaces. The SLIC was designed as a highly selective receptor and reporter protein to detect antibodies in whole blood, which are of importance in malaria diagnosis. The specific binding of the antibody to the sensor surface was monitored on-line with label-free surface-sensitive techniques either optically by surface plasmon resonance in whole blood or electrically by measuring the channel activity of SLIC in blood serum. We demonstrate the feasibility of a highly sensitive and easily applicable whole blood biosensor on the basis of simple commercially available components. The sensor might find applications in the field of infectious diseases such as point-of-care diagnostics of malaria, high content quality control of blood samples of donors, or monitoring the efficacy of vaccination. 相似文献
875.
Timo Huber Florian Manzenrieder Christian A. Kuttruff Cornelia Dorner-Ciossek Horst Kessler 《Bioorganic & medicinal chemistry letters》2009,19(15):4427-4431
Cyclization of recently reported linear phosphino dipeptide isostere inhibitors of BACE1 via side chain olefin metathesis yielded macrocyclic BACE1 inhibitors. The most potent compound II-P1 (IC50 of 47 nM) and the corresponding linear analog I were tested for serum stability. The approach led to three times prolonged half life serum stability of 44 min for the macrocyclic inhibitor II-P1 compared to the linear compound I. 相似文献
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