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431.
High activity of human butyrylcholinesterase at low pH in the presence of excess butyrylthiocholine.
Patrick Masson Florian Nachon Cynthia F Bartels Marie-Therese Froment Fabien Ribes Cedric Matthews Oksana Lockridge 《European journal of biochemistry》2003,270(2):315-324
Butyrylcholinesterase is a serine esterase, closely related to acetylcholinesterase. Both enzymes employ a catalytic triad mechanism for catalysis, similar to that used by serine proteases such as alpha-chymotrypsin. Enzymes of this type are generally considered to be inactive at pH values below 5, because the histidine member of the catalytic triad becomes protonated. We have found that butyrylcholinesterase retains activity at pH 相似文献
432.
Alain E. Reinberg Marc Riedel Cedric Riedel Eric Brousse Yvan Touitou 《Chronobiology international》2017,34(8):1158-1174
Systolic (S) and diastolic (D) blood pressures (BP) [SBP and DBP] are circadian rhythmic with period (τ) in healthy persons assumed to be maintained at 24.0h. We tested this assumption in a sample of 30 healthy career (mean >12 yrs) 30-to-46 yr-old male Caucasian French firefighters (FFs) categorized into three groups according to work schedule and duties: Group A – 12 FFs working 12h day, 12h night, and occasionally 24h shifts and whose primary duties are firefighting plus paramedical and road rescue services; Group B – 9 FFs working mostly 12h day and 12h night shifts and whose duties are answering incoming emergency calls and coordinating service vehicle dispatch from fire stations with Group A personnel; Group C – 9 day shift (09:00–17:00h) FFs charged with administrative tasks. SBP and DBP, both in winter and in summer studies of the same FFs, were sampled by ambulatory BP monitoring every 1h between 06:00–23:00h and every 2h between 23:01–05:59h, respectively, their approximate off-duty wake and sleep spans, for 7 consecutive days. Activity (wrist actigraphy) was also sampled at 1-min intervals. Prominent τ of each variable was derived by a power spectrum program written for unequal-interval time series data, and between-group differences in incidence of τ≠24h of FFs were assessed by chi square test. Circadian rhythm disruption (τ≠24h) of either the SBP or DBP rhythm occurred almost exclusively in night and 24h shift FFs of Group A and B, but almost never in day shift FFs of Group C, and it was not associated with altered τ from 24.0h of the circadian activity rhythm. In summer, occurrence of τ≠24 for FFs of Group A and B differed from that for FFs of Group C in SBP (p=0.042) and DBP (p=0.015); no such differences were found in winter (p>0.10). Overall, manifestation of prominent τ≠24h of SBP or DBP time series was greater in summer than winter, 27.6% versus 16.7%, when workload of Group B FFs, i.e. number of incoming emergency telephone calls, and of Group A FFs, i.e. number of dispatches for provision of emergency services, was, respectively, two and fourfold greater and number of 12h night shifts worked by Group B FFs and number of 24h shifts worked by Group A FFs was, respectively, 92% and 25% greater. FFs of the three groups exhibited no winter-summer difference in τ≠24h of SBP or SDP; however, τ≠24h of DBP in Group B FFs was more frequent in summer than winter (p=0.046). Sleep/wake cycle disruption, sleep deprivation, emotional and physical stress, artificial light-at-night, and altered nutrient timings are hypothesized causes of τ≠24h for BP rhythms of affected Groups A and B FFs, but with unknown future health effects. 相似文献
433.
Sina M. Adl David Bass Christopher E. Lane Julius Luke Conrad L. Schoch Alexey Smirnov Sabine Agatha Cedric Berney Matthew W. Brown Fabien Burki Paco Crdenas Ivan epi
ka Lyudmila Chistyakova Javier del Campo Micah Dunthorn Bente Edvardsen Yana Eglit Laure Guillou Vladimír Hampl Aaron A. Heiss Mona Hoppenrath Timothy Y. James Anna Karnkowska Sergey Karpov Eunsoo Kim Martin Kolisko Alexander Kudryavtsev Daniel J.G. Lahr Enrique Lara Line Le Gall Denis H. Lynn David G. Mann Ramon Massana Edward A.D. Mitchell Christine Morrow Jong Soo Park Jan W. Pawlowski Martha J. Powell Daniel J. Richter Sonja Rueckert Lora Shadwick Satoshi Shimano Frederick W. Spiegel Guifr Torruella Noha Youssef Vasily Zlatogursky Qianqian Zhang 《The Journal of eukaryotic microbiology》2019,66(1):4-119
434.
Look GC Vacin C Dias TM Ho S Tran TH Lee LL Wiesner C Fang F Marra A Westmacott D Hromockyj AE Murphy MM Schullek JR 《Bioorganic & medicinal chemistry letters》2004,14(6):1423-1426
Solid-phase synthetic methods for biaryl-based compounds were developed resulting in the construction of two 1000-member libraries. Numerous compounds were identified by high-throughput screening using whole cell screens to exhibit anti-microbial activity against Gram-positive bacteria. A series of biaryl compounds containing natural and unnatural amino acids were made to explore the SAR of the amino acid functionality. 相似文献
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437.
The accessory reproductive glands (ARG) of the male migratory grasshopper, Melanoplus sanguinipes, are able to accumulate injected labelled ARG protein from the haemolymph. Accumulation is slight in the ARG of 2-day-old virgins, or 7-day-old allatectomized (CA?) insects. The ARG of 7-day-old virgins, or 7-day-old CA? insects treated with synthetic juvenile hormone, accumulate about 1.5 times more label than those of 2-day-old insects in a 24-hr period. The ARG of recently mated males accumulate almost four times more label than those of 2-day-old controls. Immunoprecipitation studies indicate that about one fifth of the labelled protein is accumulated unchanged.The fat body and haemolymph contain proteins which are precipitable by antiserum to whole ARG homogenate. The concentration of these proteins in the fat body increases after removal of the ARG, or after copulation. It is concluded that the fat body synthesizes certain proteins which are accumulated by the ARG. Both the synthesis and the accumulation of these proteins are regulated by the corpora allata. 相似文献
438.
Michael J. Hickerson Graham N. Stone Konrad Lohse Terrence C. Demos Xiaoou Xie Cedric Landerer Naoki Takebayashi 《Evolution; international journal of organic evolution》2014,68(1):284-294
Prior specification is an essential component of parameter estimation and model comparison in Approximate Bayesian computation (ABC). Oaks et al. present a simulation‐based power analysis of msBayes and conclude that msBayes has low power to detect genuinely random divergence times across taxa, and suggest the cause is Lindley's paradox. Although the predictions are similar, we show that their findings are more fundamentally explained by insufficient prior sampling that arises with poorly chosen wide priors that critically undersample nonsimultaneous divergence histories of high likelihood. In a reanalysis of their data on Philippine Island vertebrates, we show how this problem can be circumvented by expanding upon a previously developed procedure that accommodates uncertainty in prior selection using Bayesian model averaging. When these procedures are used, msBayes supports recent divergences without support for synchronous divergence in the Oaks et al. data and we further present a simulation analysis that demonstrates that msBayes can have high power to detect asynchronous divergence under narrower priors for divergence time. Our findings highlight the need for exploration of plausible parameter space and prior sampling efficiency for ABC samplers in high dimensions. We discus potential improvements to msBayes and conclude that when used appropriately with model averaging, msBayes remains an effective and powerful tool. 相似文献
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