检索结果-南通市图书馆

Pedosphere 2024年第5期34卷 865-878页

作者： Megan l.SCHIll richard BAIRD Shawn P.BROWN Allison M.VEACH Department of Integrative Biology University of Texas at San Antonio Biochemistry Molecular Biology Entomology and Plant Pathology Department Mississippi State University Department of Biological Sciences The University of Memphis

Climate change has increased drought frequency and duration that are exacerbated by increased temperatures globally. This effect has, and will continue,to increase fire occurrence across many regions of North America. In the southern Appalachian Mountains, wildfires with high burn severity occurred in 2016due to increased drought and human activity. To investigate the effects of burn severity on soil physicochemical properties, microbial extracellular enzyme production, and microbial abundances in a temperate region, surface soils (0–15 cm) were collected from two sites (the Great Smoky Mountains National Park in Tennessee and the Nantahala National Forest in North Carolina, USA) spanning lightly, moderately, and severely burned areas, accompanied by adjacent unburned locations that act as controls. The soil samples were collected at three time points between 2017 and 2019 (i.e., 0.5, 1, and 2.5 years post-fire)among burn severity plots. Total hydrolytic enzyme production varied over time, with severe burn plots having significantly lower enzyme production at 2.5years post-fire. Individual enzymes varied among burn severities and across time post-fire. light burn plots showed greater carbon-specific (β-glucosidase and β-xylosidase) and phosphorus-specific (acid phosphatase) enzyme activities at 0.5 years post-fire, but this effect was transient. At 2.5 years post-fire, theβ-xylosidase and acid phosphatase activities were lower in severe or moderate burn plots relative to the controls. In contrast, the activity of nitrogen-specific enzyme leucyl aminopeptidase was the lowest in severe burn plots at 0.5 years post-fire, but was the lowest in light burn plots at 2.5 years post-fire. The fungi:bacteria ratio declined with burn severity, indicating that fungi are sensitive or less resilient to high burn severity during recovery. These results suggest that wildfires alter trajectories for soil microbial structure and function within a 2.5-year timeframe, which potentially

关键词： 16S rRNA burn severity extracellular enzyme fungi:bacteria ratio internal transcribed spacer microbial structure

The Effect of Retinoic Acid on Neutrophil Innate Immune Interactions With Cutaneous Bacterial Pathogens

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Infectious Microbes & Diseases 2024年第2期6卷 65-73页

作者： Alexandra Stream Ross Corriden Simon Döhrmann richard l.Gallo Victor Nizet Ericka l.Anderson Division of Host-Microbe Systems and Therapeutics Department of PediatricsUniversity of California San Diego School of MedicineLa JollaCaliforniaUSA Department of Dermatology University of California San Diego School of MedicineLa JollaCaliforniaUSA Skaggs School of Pharmacy and Pharmaceutical Sciences University of California San DiegoLa JollaCaliforniaUSA

Vitamin A and its biologically active derivative,retinoic acid(RA),are important for many immune ***,in particular,is essential for the development of immune cells,including neutrophils,which serve as a front-line defense against *** vitamin A deficiency has been linked to higher susceptibility to infections,the precise role of vitamin A/RA in host-pathogen interactions remains poorly ***,we provided evidence that RA boosts neutrophil killing of methicillin-resistant Staphylococcus aureus(MRSA).RA treatment stimulated primary human neutrophils to produce reactive oxygen species,neutrophil extracellular traps and the antimicrobial peptide cathelicidin(ll-37).Because RA treatment was insufficient to reduce MRSA burden in an in vivo murine model of skin infection,we expanded our analysis to other infectious *** did not affect the growth of a number of common bacterial pathogens,including MRSA,Escherichia coli K1 and Pseudomonas aeruginosa;however,RA directly inhibited the growth of group A Streptococcus(GAS).This antimicrobial effect,likely in combination with RA-mediated neutrophil boosting,resulted in substantial GAS killing in neutrophil killing assays conducted in the presence of ***,in a murine model of GAS skin infection,topical RA treatment showed therapeutic potential by reducing both skin lesion size and bacterial *** findings suggest that RA may hold promise as a therapeutic agent against GAS and perhaps other clinically significant human pathogens.

关键词： retinoic acid neutrophil bacterial infection Staphylococcus aureus group A Streptococcus neutrophil extracellular traps antimicrobial peptide cathelicidin

Carbon dioxide enrichment affected flower numbers transiently and increased successful post-pollination development stably but without altering final acorn production in mature pedunculate oak (Quercus robur l.)

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Forestry Research 2024年第4期35卷 1-12页

作者： Ryan McClory richard H.Ellis Martin lukac Jo Clark Carolina Mayoral Kris M.Hart Andrew R.G.Plackett A.Rob MacKenzie School of Agriculture Policy and DevelopmentUniversity of ReadingAgricultureEarley GateWhiteknights RoadPO Box 237Reading RG66EUUK Faculty of Forestry and Wood Sciences Czech University of Life Sciences PraguePrague 165000Czechia Future Trees Trust Harwell Innovation CentreBuilding 173Curie AvenueHarwellOxford OX110QGUK Birmingham Institute of Forest Research University of BirminghamEdgbastonBirmingham B152TTUK School of Biosciences University of BirminghamEdgbastonBirmingham B152TTUK School of Geography Earth and Environmental SciencesUniversity of BirminghamEdgbastonBirmingham B152TTUK

Acorn production in oak(Quercus spp.)shows considerable inter-annual variation,known as masting,which provides a natural defence against seed predators but a highly-variable supply of acorns for uses such as in commercial tree planting each *** emissions of greenhouse gases have been very widely reported to influence plant growth and seed or fruit size and quantity via the‘fertilisation effect’that leads to enhanced *** examine if acorn production in mature woodland communities will be affected by further increase in CO_(2),the contents of litter traps from a Free Air Carbon Enrichment(FACE)experiment in deciduous woodland in central England were analysed for numbers of flowers and acorns of pedunculate oak(Quercus robur l.)at different stages of development and their predation levels under ambient and elevated CO_(2) ***-annual variation in acorn numbers was considerable and cyclical between 2015 and 2021,with the greatest numbers of mature acorns in 2015,2017 and 2020 but almost none in *** numbers of flowers,enlarged cups,immature acorns,empty acorn cups,and galls in the litter traps also varied amongst years;comparatively high numbers of enlarged cups were recorded in 2018,suggesting *** at this site is a fruit maturation masting species(i.e.,the extent of abortion of pollinated flowers during acorn development affects mature acorn numbers greatly).Raising the atmospheric CO_(2) concentration by 150μl l^(−1),from early 2017,increased the numbers of immature acorns,and all acorn evidence(empty cups+immature acorns+mature acorns)detected in the litter traps compared to ambient controls by 2021,but did not consistently affect the numbers of flowers,enlarged cups,empty cups,or mature *** number of flowers in the elevated CO_(2) plots’litter traps was greater in 2018 than 2017,one year after CO_(2) enrichment began,whereas numbers declined in ambient *** with CO_(2) also increased the number o

关键词： Quercus robur l. Acorns Masting Pedunculate oak Carbon dioxide

Are there sex-based disparities in cataract surgery?

在线全文

学校读者我要写书评

暂无评论

International Journal of Ophthalmology(English edition) 2024年第1期17卷 137-143页

作者： Matthew D.Geiger Anne M.lynch Alan G.Palestine Nathan C.Grove Karen l.Christopher richard S.Davidson Michael J.Taravella Naresh Mandava Jennifer l.Patnaik Department of Ophthalmology University of Colorado School of MedicineAuroraCO 80045USA

AIM:To investigate sex-based differences in the occurrence of intra-operative and post-operative complications and associated visual outcomes following cataract ***:This was a retrospective study of patients who had phacoemulsification cataract surgery at the University of Colorado School of *** collected included the patient’s health history,ocular comorbidities,operative and post-operative complications,and the post-operative best corrected visual acuity(BCVA).The data were analyzed using univariate and multivariable logistic regression with generalized estimating equations to account for the correlation of some patients having two eyes included in the ***:A total of 11977 eyes from 7253 patients were included in the *** comorbidities differed by sex,with males having significantly higher percentages of traumatic cataracts(males 0.7%vs females 0.1%),prior ocular surgery(6.7%vs 5.5%),and mature cataracts(2.8%vs 1.9%).Conversely,females had significantly higher rates of pseudoexfoliation(2.0%vs 3.2%).In unadjusted analysis,males had higher rates of posterior capsular rupture(0.8%vs 0.4%)and vitreous loss(1.0%vs 0.6%),but this difference was not significant after adjustment for *** had a significantly increased risk of post-operative retinal detachment,but in multivariable analysis this was no longer *** were significantly less likely to undergo post-operative neodymium-doped yttrium aluminum garnet(Nd:YAG)laser capsulotomy for posterior capsule opacification(OR=0.8,95%CI=0.7-0.9,P=0.0005).The BCVA was slightly worse for males pre-operatively;but post-operatively,both sexes exhibited similar visual acuity of Snellen equivalent 20/***:The study finds that in a cohort of patients presenting for cataract surgery,sex differences exist in pre-operative comorbidities and surgical characteristics that contribute to higher rates of some complications for ***,observed surgical complicatio

关键词： cataract surgery sex-based disparity phacoemulsification outcomes

COVID-19 vaccination produces exercise-responsive SARS-CoV-2 specific T-cells regardless of infection history

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Sport and Health Science 2024年第1期13卷 99-107页

作者： Kyle A.Smith Tiffany M.Zúñiga Forrest l.Baker Helena Batatinha Charles R.Pedlar Shane C.Burgess Michael P.Gustafson Emmanuel Katsanis richard J.Simpson School of Nutritional Sciences and Wellness The University of ArizonaTucsonAZ 85721USA Department of Pediatrics The University of ArizonaTucsonAZ 85724USA Faculty of Sport Allied Health and Performance ScienceSt.Mary's UniversityTwickenham TW14SXUK Institute of Sport Exercise and Health University College LondonLondon WC1E 7HUUK Department of Animal and Comparative Biomedical Sciences The University of ArizonaTucsonAZ 85721USA The University of Arizona Cancer Center The University of ArizonaTucsonAZ 85719USA laboratory Medicine and Pathology Mayo Clinic ArizonaPhoenixAZ 85054USA Department of Immunobiology The University of ArizonaTucsonAZ 85724USA Department of Medicine The University of ArizonaTucsonAZ 85724USA Department of Pathology The University of ArizonaTucsonAZ 85724USA

Background:The mobilization and redistribution of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)specific T-cells and neutralizing antibodies(nAbs)during exercise is purported to increase immune surveillance and protect against severe coronavirus disease 2019(COVID-19).We sought to determine if COVID-19 vaccination would elicit exercise-responsive SARS-CoV-2 T-cells and transiently alter nAb ***:Eighteen healthy participants completed a 20-min bout of graded cycling exercise before and/or after receiving a COVID-19 *** major leukocyte subtypes were enumerated before,during,and after exercise by flow cytometry,and immune responses to SARS-CoV-2 were determined using whole blood peptide stimulation assays,T-cell receptor(TCR)-βsequencing,and SARS-CoV-2 nAb ***:COVID-19 vaccination had no effect on the mobilization or egress of major leukocyte subsets in response to intensity-controlled graded ***,non-infected participants had a significantly reduced mobilization of CD4+and CD8+naive T-cells,as well as CD4+central memory T-cells,after vaccination(synthetic immunity group);this was not seen after vaccination in those with prior SARS-CoV-2 infection(hybrid immunity group).Acute exercise after vaccination robustly mobilized SARS-CoV-2 specific T-cells to blood in an intensity-dependent *** groups mobilized T-cells that reacted to spike protein;however,only the hybrid immunity group mobilized T-cells that reacted to membrane and nucleocapsid *** increased significantly during exercise only in the hybrid immunity ***:These data indicate that acute exercise mobilizes SARS-CoV-2 specific T-cells that recognize spike protein and increases the redistribution of nAbs in individuals with hybrid immunity.

关键词： Anti-viral COVID-19 Exercise immunology SARS-CoV-2 T-Cells Vaccine

Nutritional Considerations in High Performance Youth Soccer:A Systematic Review

在线全文

学校读者我要写书评

暂无评论

Journal of Science in Sport and Exercise 2022年第3期4卷 195-212页

作者： Matthew North Adam l.kelly Mayur K.Ranchordas Matthew Cole Research Centre for life and Sport Sciences(ClaSS) Birmingham City UniversityBirminghamWest MidlandsUK Academy of Sport and Physical Activity&Advanced Wellbeing Research Centre Sheffield Hallam UniversityCollegiate Crescent CampusSheffieldYorkshireUK

Purpose As players in high performance youth soccer(HYPS)environments undergo large changes in growth and matura-tion throughout the course of their development,they require specific nutritional intakes if they are to meet these *** purpose of this review was to synthesise current nutritional research conducted within HYPS *** A systematic approach,following PRISMA guidelines,was employed to capture all articles related to nutrition within HPYS using the databases MEDlINE and *** quality and risk of bias were assessed using a Downs and Black *** and intervention studies which investigated an element of nutritional status,knowledge,or intervention in academy aged players(U9 to U23s)within HPYS settings were *** Fifty-three articles qualified assessing:current nutritional intake and energy balance(n=21);ergogenic aids/sup-plements(n=13);hydration status(n=6);the influence of Ramadan fasting(n=4);Vitamin D status(n=4);female HPYS players(n=3);nutrition knowledge(n=2).Outcomes demonstrate a large proportion of HPYS players exhibit insufficient energy and carbohydrate intake,and a lack sufficient periodisation of nutrition to account for varying training/match *** variability in energy intake and expenditure exists between and within chronological age groups,indicating the potential impact on growth and *** HPYS data is lacking but indicates similar trends to male *** HYPS players do not currently meet their energy requirements however the impact of growth and maturation is not fully ***,within this demographic future research is required into the barriers and enablers of players achieving adequate energy intake.

关键词： Nutrition Youth soccer Nutritional intake Supplements Hydration

Effects of B[a]P-UVA Co-Exposure on Epigenetic Marks of Isolated Skin Cells and Impact of an Arundo donax l. Extract of These Changes

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Cosmetics, Dermatological Sciences and Applications 2024年第3期14卷 253-269页

作者： Marie M. Dorr Magali Favre-Mercuret Katell Vié richard Fitoussi laboratoires Clarins Pontoise France

Background: Extrinsic aging results from environmental stressors such as UVR or pollutants. While the effects of single pollutants are better understood, those of their combination remain poorly scrutinized. Objective: Building on a study showing downregulation of several processes upon co-exposure to B[a]P and UVA, we investigated changes induced by epigenetic marks. Materials and Methods: Human primary fibroblasts and HaCaT cells were exposed to B[a]P and UVA. After 24 hours, exposed and unexposed cells were compared to assess DNA methylation. Focusing on HaCaT, multiplex assays enabled quantifying histone H3 modifications and evaluating four splicing factors (SRSF1, SRSF3, SFPQ, and SF3B1) by immunohistochemical labeling. The expression of keratinocyte-/fibroblast-relevant genes was assessed by RT-qPCR. Finally, the impact of an Arundo donax l. extract added 24 hours before B[a]P-UVA co-exposure was analyzed. Results: Exposure to B[a]P-UVA raised DNA methylation (HaCaT: ×3.6, fibroblasts: ×1.9), an increase prevented by the extract. In HaCaT cells, B[a]P-UVA increases the frequency of S10P (+38%). When exposure was preceded by extract treatment, the frequency of several methylations was impacted. B[a]P-UVA only induced the expression of SRSF1 and SFPQ in HaCaT (+46% and +34%). Treatment with the extract abolished this effect. Co-exposure increases the expression of inflammation-related genes (Il-1α, Il-1β) in HaCaT cells and decreases those of AQP3, KRT15, and SOD2. The extract has little effect on these changes. In primary fibroblasts, exposure to B[a]P-UVA lowered the expression of lOXl2, lUM, and TGFBR2 (−38%, −59%, and −51%, respectively), and the extract did not affect these modifications. Conclusion: Within 24 hours, a single B[a]P-UVA co-exposure changes epigenetic marks of skin cells but has only mild effects on gene expression. An Arundo donax l. extract can prevent part of the epigenetic marks’ changes and could stimulate the expression of some genes in

关键词： Extrinsic Aging DNA Methylation Histone H3 Splicing Factors Arundo donax l.

On the functions of astrocyte-mediated neuronal slow inward currents

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Neural Regeneration Research 2024年第12期19卷 2602-2612页

作者： Balázs Pál Department of Physiology Faculty of MedicineUniversity of DebrecenDebrecenHungary

Slow inward currents are known as neuronal excitatory currents mediated by glutamate release and activation of neuronal extra synaptic N-met hyl-D-aspartate receptors with the contribution of *** events are significantly slower than the excitatory postsynaptic *** of slow inward currents are determined by seve ral factors including the mechanisms of astrocytic activation and glutamate release,as well as the diffusion pathways from the release site towards the extra synaptic recepto *** are stimulated by neuronal network activity,which in turn excite neurons,forming an astrocyte-neuron feedback *** as a consequence of brain edema,astrocytic swelling can also induce slow inward currents under pathological *** is a growing body of evidence on the roles of slow inward currents on a single neuron or local network *** events often occur in synchro ny on neurons located in the same astrocytic *** synchronization of neuronal excitability,slow inward currents also set synaptic strength via eliciting timing-dependent synaptic *** addition,slow inward currents are also subject to non-synaptic plasticity triggered by long-la sting stimulation of the excitatory *** note,there might be important regionspecific differences in the roles and actions triggering slow inward *** greater networks,the pathophysiological roles of slow inward currents can be better understood than physiological *** inward currents are identified in the pathophysiological background of autism,as slow inward currents drive early hypersynchrony of the neural *** inward currents are significant contributors to paroxysmal depolarizational shifts/interictal *** events are related to epilepsy,but also found in Alzheimer's disease,Parkinson's disease,and stroke,leading to the decline of cognitive *** with features overlapping with slow inward currents(excitatory,N-methyl-Dasp

关键词： astrocyte cortical spreading depolarization gliotransmission glutamate neural synchronization NMDA receptor paroxysmal depolarizational shift slow inward current

On calculating glacial isostatic adjustment

在线全文

学校读者我要写书评

暂无评论

Geodesy and Geodynamics 2024年第5期15卷 441-452页

作者： l.M.Cathles Cornell University IthacaNY 14853USA

Modeling the earth's fluid and elastic response to the melting of the glaciers of the last ice age is the most direct way to infer the earth's radial viscosity ***,we compare two methods for calculating the viscoelastic response to surface *** one,the elastic equation of motion is converted to a viscoelastic equation using the Correspondence *** the other,elastic deformation is added to the viscous flow as isostatic adjustment *** two modeling methods predict adjustment histories that are different enough to potentially impact the interpretation of the observed glacial isostatic adjustment(GIA).The differences arise from buoyancy and whether fluid displacements are subjected to hydrostatic *** methods agree if they use the same equations and boundary *** origin of the differences is determined by varying the boundary conditions and pre-stress application.

关键词： Glacial isostatic adjustment Viscoelastic normal modes Hydrostatic pre-stress Elastic buoyancy Correspondence principle