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991.
Manfred Schartl Susanne Kneitz Jenny Ormanns Cornelia Schmidt Jennifer L. Anderson Angel Amores Julian Catchen Catherine Wilson Dietmar Geiger Kang Du Mateo Garcia-Olazábal Sudha Sudaram Christoph Winkler Rainer Hedrich Wesley C. Warren Ronald Walter Axel Meyer John H. Postlethwait 《Current biology : CB》2021,31(5):911-922.e4
992.
993.
Carsten Schwarz Jean-Philippe Bouchara Walter Buzina Vanda Chrenkova Hanna Dmeńska Elia Gomez Garcia de la Pedrosa Rafael Cantón Ersilia Fiscarelli Yohann Le Govic Nahid Kondori Tadeja Matos Ewa Romanowska Stefan Ziesing Ludwig Sedlacek 《Mycopathologia》2018,183(1):7-19
The achievement of a better life for cystic fibrosis (CF) patients is mainly caused by a better management and infection control over the last three decades. Herein, we want to summarize the cornerstones for an effective management of CF patients and to give an overview of the knowledge about the fungal epidemiology in this clinical context in Europe. Data from a retrospective analysis encompassing 66,616 samples from 3235 CF patients followed-up in 9 CF centers from different European countries are shown. 相似文献
994.
The ATR-mediated checkpoint is not only critical for responding to genotoxic stress but also essential for cell proliferation. The RFC-related checkpoint protein Rad17, a phosphorylation substrate of ATR, is critical for ATR-mediated checkpoint signaling and cell survival. Here, we show that phosphorylation of Rad17 by ATR is important for genomic stability and restraint of S phase but is not essential for cell survival. The phosphomutant Rad17AA exhibits distinct defects in hydroxyurea- (HU) and ultraviolet- (UV) induced Chk1 activation, indicating that separate Rad17 functions are required differently in response to different types of replication interference. Although cells expressing Rad17AA can initiate Chk1 phosphorylation after HU treatment, they fail to sustain Chk1 phosphorylation after withdrawal of HU and are profoundly sensitive to HU. Importantly, we found that phosphorylated Rad17 interacts with Claspin and regulates its phosphorylation. These findings reveal a phosphorylation-dependent function of Rad17 in an ATR-Rad17-Claspin-Chk1-signaling cascade that responds to specific replication stress. 相似文献
995.
Small monomeric G-proteins control cellular behavior, cycling between inactive GDP-bound and active GTP-bound states. Activating and deactivating transitions are regulated by guanine nucleotide exchange factors (GEFs) and GTPase activating proteins (GAPs), respectively. G-proteins can control different GEF and GAP activities, thereby creating GTPase signaling cascades. Here, we characterize all 128 different wiring topologies of two-layer cascades, which include feedforward/feedback interactions and an auto-regulatory loop. Exclusion of "mirror" designs leaves 64 topologies, which are classified into eight groups. We demonstrate that eight different cascades in each group generate the same number of steady states and similar spatiotemporal dynamics. Two groups (featuring 16 topologies) can generate three distinct dynamics: (i) bistable switches, (ii) excitable behavior, and (iii) sustained oscillations, giving rise to propagating waves of G-protein activation switches and pulses. Four other groups can produce switch-like, bistable behaviors and trigger waves. The remaining two groups have a single steady state. This first, complete classification of all possible interaction circuitries systematically links topological design to the spatiotemporal dynamics of G-protein cascades, predicting and explaining experimentally observed behavior. 相似文献
996.
Walter Narchi 《Studies on Neotropical Fauna and Environment》2013,48(4):205-210
Meiocardia agassizii Dall, 1886 is a bivalve that belongs to the family Glos‐sidae, Gray 1847. Described by Dall in 1886, it was dredged by the U.S. Fish Commission off Trinidad from a depth of 210 m. The same species was dredged for the first time in the South Atlantic off the mouth of Rio Doce, Espirito Santo, Brazil. As the specimen was well preserved the study of the soft parts was possible. The mantle, siphons and the organs of the mantle cavity were described and compared to those of Glossus humanus, which belongs to the same family. 相似文献
997.
Ljubinka Francuski Walter Jansen Leo W. Beukeboom 《Entomologia Experimentalis et Applicata》2020,168(6-7):513-522
Musca domestica L. (Diptera: Muscidae), better known as the common housefly, is increasingly considered to be a new, alternative protein source for animal nutrition. By transferring low-value organic side streams into high-value protein products, its commercial production contributes to a circular economy. Next to technical innovations for scaling-up the production capacity, efficient egg production has been identified as one of the bottlenecks of housefly production systems. We investigated egg production in two strains, one originally from Spain (SPA) and one from The Netherlands (GK), at 25 and 32 °C. At 25 °C, duration of preoviposition period, laying phase, and adult longevity was longer than at 32 °C. Lifetime egg production was lower at 32 °C, but the number of clutches laid per female was unaffected by temperature. Daily egg production at 32 °C was higher during the first 7 days, revealing a trade-off between higher early-in-life reproductive effort and adult longevity. The combination of shorter sexual maturation period and higher daily egg-laying rate resulted in reaching 50% of total egg production only 6 days after emergence at 32 °C for both strains, compared to 13 and 14 days at 25 °C for SPA and GK, respectively. We conclude that, in the absence of a need for high adult survival rates, houseflies have favourable production performances at higher temperature, and that efficacy and yield of the production process could be maximized by increasing the rearing temperature to 32 °C. 相似文献
998.
Richard D. Telford Ross B. Cunningham Rohan M. Telford Malcolm Riley Walter P. Abhayaratna 《PloS one》2012,7(11)
Background
To contribute to the current debate as to the relative influences of dietary intake and physical activity on the development of adiposity in community-based children.Methods
Participants were 734 boys and girls measured at age 8, 10 and 12 years for percent body fat (dual emission x-ray absorptiometry), physical activity (pedometers, accelerometers); and dietary intake (1 and 2-day records), with assessments of pubertal development and socioeconomic status.Results
Cross-sectional relationships revealed that boys and girls with higher percent body fat were less physically active, both in terms of steps per day and moderate and vigorous physical activity (both sexes p<0.001 for both measures). However, fatter children did not consume more energy, fat, carbohydrate or sugar; boys with higher percent body fat actually consumed less carbohydrate (p = 0.01) and energy (p = 0.05). Longitudinal analysis (combined data from both sexes) was weaker, but supported the cross-sectional findings, showing that children who reduced their PA over the four years increased their percent body fat (p = 0.04). Relationships in the 8 year-olds and also in the leanest quartile of all children, where adiposity-related underreporting was unlikely, were consistent with those of the whole group, indicating that underreporting did not influence our findings.Conclusions
These data provide support for the premise that physical activity is the main source of variation in the percent body fat of healthy community-based Australian children. General community strategies involving dietary intake and physical activity to combat childhood obesity may benefit by making physical activity the foremost focus of attention. 相似文献999.
Tina Sartorius Andreas Peter Martin Heni Walter Maetzler Andreas Fritsche Hans-Ulrich H?ring Anita M. Hennige 《PloS one》2015,10(5)
ObjectivesIt is a matter of debate whether impaired insulin action originates from a defect at the neural level or impaired transport of the hormone into the brain. In this study, we aimed to investigate the effect of aging on insulin concentrations in the periphery and the central nervous system as well as its impact on insulin-dependent brain activity.MethodsInsulin, glucose and albumin concentrations were determined in 160 paired human serum and cerebrospinal fluid (CSF) samples. Additionally, insulin was applied in young and aged mice by subcutaneous injection or intracerebroventricularly to circumvent the blood-brain barrier. Insulin action and cortical activity were assessed by Western blotting and electrocorticography radiotelemetric measurements.ResultsIn humans, CSF glucose and insulin concentrations were tightly correlated with the respective serum/plasma concentrations. The CSF/serum ratio for insulin was reduced in older subjects while the CSF/serum ratio for albumin increased with age like for most other proteins. Western blot analysis in murine whole brain lysates revealed impaired phosphorylation of AKT (P-AKT) in aged mice following peripheral insulin stimulation whereas P-AKT was comparable to levels in young mice after intracerebroventricular insulin application. As readout for insulin action in the brain, insulin-mediated cortical brain activity instantly increased in young mice subcutaneously injected with insulin but was significantly reduced and delayed in aged mice during the treatment period. When insulin was applied intracerebroventricularly into aged animals, brain activity was readily improved.ConclusionsThis study discloses age-dependent changes in insulin CSF/serum ratios in humans. In the elderly, cerebral insulin resistance might be partially attributed to an impaired transport of insulin into the central nervous system. 相似文献
1000.