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Are Northeastern U.S. forests vulnerable to extreme drought?

Ecological Processes 2017年第1期6卷 351-363页

作者： Adam P.Coble Matthew A.Vadeboncoeur Z.Carter Berry Katie A.Jennings Cameron D.McIntire John L.Campbell Lindsey E.Rustad pamela h.templer heidi Asbjornsen Department of Natural Resources and the Environment University of New Hampshire56 College Rd.114 James HallDurhamNH 03824USA. Earth Systems Research Center University of New Hampshire8 College RoadDurhamNH 03824USA. Northern Research Station USDA Forest Service271 Mast RoadDurhamNH 03824USA. Department of Biology Boston University5 Cummington MallBostonMA 02215USA.

In the Northeastern U.S.,drought is expected to increase in frequency over the next century,and therefore,the responses of trees to drought are important to *** is recent debate about whether land-use change or moisture availability is the primary driver of changes in forest species composition in this *** argue that fire suppression from the early twentieth century to present has resulted in an increase in shade-tolerant and pyrophobic tree species that are drought intolerant,while others suggest precipitation variability as a major driver of species *** this debate,an emerging hypothesis is that mesophication and increases in the abundance of mesophytic genera(e.g.,Acer,Betula,and Fagus)resulted in forests that are more vulnerable to *** review examines the published literature and factors that contribute to drought vulnerability of Northeastern *** assessed two key concepts related to drought vulnerability,including drought tolerance(ability to survive drought)and sensitivity(short-term responses to drought),with a focus on Northeastern *** assessed drought-tolerance classifications for species,which revealed both consistencies and inconsistencies,as well as contradictions when compared to actual observations,such as higher mortality for drought-tolerant *** to drought sensitivity,recent work has focused on isohydric/anisohydric regulation of leaf water ***,based on the review of the literature,we conclude that drought sensitivity should be viewed in terms of multiple variables,including leaf abscission,stomatal sensitivity,turgor pressure,and dynamics of non-structural *** considered drought sensitive(e.g.,Acer,Betula,and Liriodendron)may actually be less prone to drought-induced mortality and dieback than previously considered because stomatal regulation and leaf abscission in these species are effective at preventing water potential from reaching critica

关键词： Acer Betula Drought sensitivity Drought tolerance Quercus Northeastern U.S. Temperate deciduous

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Porphyromonas gingivalis Resistance to Polymyxin B Is Determined by the Lipid A 4’-Phosphatase, PGN_0524

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International Journal of Oral Science 2009年第3期1卷 126-135页

作者： Stephen R. Coats Thao T. To Sumita Jain pamela h. Braham Richard P. Darveau Department of Periodontics School of Dentistry University of Washington Seattle USA

Aim To elucidate the genetic basis for the pronounced resistance that the oral pathogen, Porphyromonas gingivalis （P. gingivalis）, exhibits towards the cationic antimicrobial peptide, polymyxin B. Methodology A genetic screen of P. gingivalis clones generated by a Tn4400-based random insertion mutagenesis strategy was performed to identify bacteria harboring novel genetic mutations that render P. gingivalis susceptible to killing by the cationic antimicrobial peptide, polymyxin B （PMB, 50μg·mL^-1）. Results P. gingivalis （ATCC 33277） is unusually resistant to the cationic antimicrobial peptide, PMB at relatively high concentrations （200μg·mL^-1）. Approximately 2,700 independent Tn4400 ＇-derived mutants ofP. gingivalis were examined for increased sensitivity to PMB killing at a relatively low dose （50 μg·mL^-1）. A single PMB-sensitive mutant was obtained in this phenotypic screen. We determined that the Tn4400＇ transposon was integrated into the gene encoding the lipid A 4＇-phosphatase, PGN 0524, demonstrating that this insertion event was responsible for its increased susceptibility of this clone to PMB-dependent killing. The resulting mutant strain, designated 0524-Tn4400＇, was highly sensitive to PMB killing relative to wild-type P. gingivalis, and exhibited the same sensitivity as the previously characterized strain, 0524KO, which bears a genetically engineered deletion in the PGN_0524 locus. Positive ion mass spectrometric structural （MALDI-TOF MS） analyses revealed that lipid A isolates from 0524-Tn4400＂ and 0524KO strains displayed strikingly similar MALDI-TOF MS spectra that were substantially different from the wildtype P gingivalis lipid A spectrum. Finally, intact 0524- Tn4400＇ and 0524KO mutant bacteria, as well as their corresponding LPS isolates, were significantly more potent in stimulating Toll-like receptor 4 （TLR4）-dependent E-selectin expression in human endothelial cells relative to intact wild-type P.. gingivalis or its corresponding LPS isolate.

关键词： P. gingivalis antimicrobial peptide lipid A phosphatase polymyxin B transposon lipopolysaccharide

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Kitchen waste valorization through a mildtemperature pretreatment to enhance biogas production and fermentability:Kinetics study in mesophilic and thermophilic regimen

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Journal of Environmental Sciences 2020年第3期32卷 167-179页

作者： Agata Gallipoli Camilla MBraguglia Andrea Gianico Daniele Montecchio pamela Pagliaccia Water Research Institute IRSA-CNR Area Della Ricerca RM100015 MonterotondoRomaItaly

Biowaste valorization through anaerobic digestion is an attractive option to achieve both climate protection goals and renewable energy *** this paper,a complete set of batch trials was carried out on kitchen waste to investigate the effects of mild thermal pretreatment,temperature regimen and substrate/inoculum *** pretreatment was effective in the solubilisation of macromolecular fractions,particularly *** ability of the theoretical methodologies in estimating hydrogen and methane yields of complex substrates was evaluated by comparing the experimental results with the theoretical *** the single batch configuration,a significant initial hydrogen production was observed,prior to methane *** pretreatment effect was the gain in hydrogen production;the extent was highly variable according to the other parameters *** hydrogen yields,up to 113 mL h2/g VSfed,were related to the prompt transformation of soluble *** regimen resulted,as expected,in faster digestions(up to 78 mL Ch4/gVS/day) and sorted out ph *** relatively low methane yields(342-398 mL Ch4/g VSfed) were the result of the consistent lignocellulosic content and low lipid *** pretreatment proved to be a promising option for the enhancement of hydrogen production in food waste dark fermentation.

关键词： Kitchen waste hydrogen Methane Thermal pretreatment Kinetics Thermophilic regimen

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Impacts of brood parasitism by shiny cowbird Molothrus bonariensis on the breeding success of a small host, the black-backed water tyrant Fluvicola albiventer

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Current Zoology 2024年第4期70卷 539-547页

作者： Lorena Vanesa Sovrano Evelina Jesica Leon Rodrigo Ezequiel Lorenzón pamela Fernanda Olguin Adolfo héctor Beltzer Alejandro Raúl Giraudo Laboratorio de Biodiversidad y Conservacion de Tetrapodos Instituto Nacional de Limnologia(INALICONICET-UNL)Paraje El Pozo s/nSanta Fe(3000)Argentina Departamento de Biologia Universidad Autonoma de Entre RiosKm 10.5 RP 11Oro Verde(3100)Entre RiosArgentina Departamento de Biologia Universidad Nacional del LitoralFacultad de Humanidades y CienciasParaje Ei Pozo s/nSanta Fe(3000)Argentina

The shiny cowbird Molothrus bonariensis parasitizes many species with different life-history traits and has a detrimental effect on the survival of the progeny of the *** response,hosts have developed numerous antiparasitic ***,we examined the effects of brood parasitism by shiny cowbird on the clutch and brood sizes(83 nests)in a small host,the black-backed water tyrant Fluvicola *** also studied whether the death of parasite nestlings was related to the care of the foster parents and whether the host had any antiparasitic defense against the shiny *** results indicate that brood parasitism significantly decreased the host hatching and fledging *** majority of nest failures(57%)were caused by brood *** cowbird parasitism occurred in 52%of nests and the intensity of parasitism was 1.23±0.53 eggs per parasitized *** the total host eggs,54%were *** the incubation stage,20 nests(47%)were abandoned because of egg punctures by shiny cowbirds *** two parasitic fledglings were recorded,while the remaining nestlings either died from starvation(n=12)or predation(n=3).Foster parents abandoned parasitic nestlings between 5 and 10 days *** findings demonstrate that the shiny cowbird has very low rates of fledging success when parasitizing black-backed water ***,parasitism had a high reproductive cost in the black-backed water tyrant because a very low proportion(7%)of the parasitized nests(n=43)were successful.

关键词： brood parasitism host defenses nest desertion shiny cowbird small host.

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Immunotherapy with immune checkpoint inhibitors in colorectal cancer:what is the future beyond deficient mismatch-repair tumours?

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Gastroenterology Report 2020年第1期8卷 11-24,I0001页

作者： Nicolas huyghe pamela Baldin Marc Van den Eynde Institut de Recherche Clinique et Expe´rimentale(Pole MIRO) UCLouvainBrusselsBelgium Department of Pathology Cliniques Universitaires St-LucInstitut Roi Albert IIBrusselsBelgium Department of Medical Oncology Cliniques Universitaires St-LucInstitut Roi Albert IIBrusselsBelgium

Following initial success in melanoma and lung tumours,immune checkpoint inhibitors(ICIs)are now well recognized as a major immunotherapy treatment modality for multiple types of solid *** colorectal cancer(CRC),the small subset that is mismatch-repair-deficient and microsatellite-instability-high(dMMR/MSI-h)derive benefit from immunotherapy;however,the vast majority of patients with proficient MMR(pMMR)or with microsatellite stable(MSS)CRC do *** and the consensus molecular subtype classifications are promising biomarkers in predicting therapeutic efficacy in selected *** pMRR/MSS CRC,biomarkers are also needed to understand the molecular mechanisms governing immune reactivity and to predict their relationship to *** continuous development of such biomarkers would offer new perspectives and more personalized treatments by targeting oncological options,including ICIs,which modify the tumour-immune *** this review,we focus on CRC and discuss the current status of ICIs,the role of biomarkers to predict response to immunotherapy,and the approaches being explored to render pMMR/MSS CRC more immunogenic through the use of combined therapies.

关键词： colorectal cancer immunotherapy immune checkpoint inhibitors immune response immunoscore

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hericium Erinaceus (Bull.:Fr.) Pers.,A Medicinal Mushroom,Activates Peripheral Nerve Regeneration

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Chinese Journal of Integrative Medicine 2016年第10期22卷 759-767页

作者： Kah-hui Wong Gowri Kanagasabapathy Murali Naidu pamela David Vikineswary Sabaratnam Department of Anatomy Faculty of Medicine University of Malaya Mushroom Research Centre University of Malaya Institute of Biological Sciences Faculty of Science University of Malaya

Objective： To study the ability of aqueous extract of hericium erinaceus mushroom in the treatment of nerve injury following peroneal nerve crush in Sprague-Dawley rats. Methods： Aqueous extract of hericium erinaceus was given by daily oral administration following peroneal nerve crush injury in Sprague- Dawley rats. The expression of protein kinase B （Akt） and mitogen-activated protein kinase （MAPK） signaling pathways; and c-Jun and c-Fos genes were studied in dorsal root ganglia （DRG） whereas the activity of protein synthesis was assessed in peroneal nerves by immunohistochemical method. Results： Peripheral nerve injury leads to changes at the axonal site of injury and remotely located DRG containing cell bodies of sensory afferent neurons. Immunofluorescence studies showed that DRG neurons ipsilateral to the crush injury in rats of treated groups expressed higher immunoreactivities for Ak＇t, MAPK, c-Jun and c-Fos as compared with negative control group （P〈0.05）. The intensity of nuclear ribonucleoprotein in the distal segments of crushed nerves of treated groups was significantly higher than in the negative control group （P〈0.05）. Conclusion： h. erinaceus is capable of promoting peripheral nerve regeneration after injury. Potential signaling pathways include Akt, MAPK, c-Jun, and c-Fos, and protein synthesis have been shown to be involved in its action.

关键词： hericium erinaceus dorsal root ganglia signaling pathways gene expression protein synthesis machinery peripheral nerve regeneration

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Anti-inflammatory activity of the essential oils of Cymbopogon validus(Stapf) Stapf ex Burtt Davy from Eastern Cape, South Africa

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Asian Pacific Journal of Tropical Medicine 2016年第5期9卷 415-419页

作者： pamela Rungqu Opeoluwa Oyedeji Benedicta Nkeh-Chungag Sandile Songca Oluwatobi Oluwafemi Adebola Oyedeji Department of Chemistry Faculty of Science and Agriculture University of Fort Hare Department of Biological and Environmental Sciences Faculty of Natural Sciences Walter Sisulu University Department of Chemical and Physical Sciences Faculty of Natural Sciences Walter Sisulu University Department of Applied Chemistry Faculty of Sciences University of Johannesburg

Objective: To evaluate the essential oil composition and the anti-inflammatory activity of Cymbopogon validus(C. validus) leaves and flowers. Methods: A total of 300 g of fresh or dry(leaves and flowers) of C. validus were cut into small pieces and subjected to hydro-distillation method for approximately 5 h using the Clevenger apparatus. The extracted essential oils were then used for testing the anti-inflammatory activity. The anti-inflammatory activity was evaluated by using egg-albumin induced paw edema. Results: The extracted oils had the following yields 2.2% for fresh leaves, 2.0% for dry leaves and 2.4% v/w for dry flowers. GCMS results revealed that the oils contained artemisia ketone(37.5%), linalool(3.2%-29.6%), northujane(4.4%-16.8%), verbenone(13.5%), naphthalene(1.7%-9.6%), δ-cadinene(0.5%-8.1%), hedycaryol(5.4%-7.6%) and α-eudesmol(6.5%-6.7%) as the major constituents. C. validus essential oils showed significant(Phe first 30 min after albumin injection compared to aspirin which had a later onset of effect. Conclusions: The findings of this study show that the essential oil extracted from C. validus fresh or dry leaves and flowers have anti-inflammatory properties; that might be associated with the major components and the minor components found in the essential oils.

关键词： Cymbopogon validus Essential oils Anti-inflammation Artemisia ketone Linalool Egg albumin-induced edema

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Biomimetic three-layered membranes comprising(poly)-e-caprolactone,collagen and mineralized collagen for guided bone regeneration

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Regenerative Biomaterials 2021年第6期8卷 218-229页

作者： Jingjing Wu Mengyu Yao Yonggang Zhang Zefeng Lin Wenwu Zou Jiaping Li pamela habibovic Chang Du Department of Biomedical Engineering School of Materials Science and EngineeringSouth China University of TechnologyGuangzhou 510641PR China National Engineering Research Center for Tissue Restoration and Reconstruction South China University of TechnologyGuangzhou 510006PR China Key Laboratory of Biomedical Materials and Engineering of the Ministry of Education and Innovation Center for Tissue Restoration and ReconstructionSouth China University of TechnologyGuangzhou 510006PR China Department of Instructive Biomaterials Engineering MERLN Institute for Technology-Inspired Regenerative MedicineMaastricht UniversityMaastricht 6229 ERthe Netherlands

The distinct structural properties and osteogenic capacity are important aspects to be taken into account when developing guided bone regeneration ***,inspired by the structure and function of natural periosteum,we designed and fabricated using electrospinning a fibrous membrane comprising(poly)-e-caprolactone(PCL),collagen-I(Col)and mineralized Col(MC).The three-layer membranes,having PCL as the outer layer,PCL/Col as the middle layer and PCL/Col/MC in different ratios(5/2.5/2.5(PCM-1);3.3/3.3/3.3(PCM-2);4/4/4(PCM-3)(%,w/w/w))as the inner layer,were *** physiochemical properties of the different layers were investigated and a good integration between the layers was *** three-layeredmembranes showed tensile properties in the range of those of natural ***,the membranes exhibited excellent water absorption capability without changes of the *** vitro experiments showed that the inner layer of the membranes supported attachment,proliferation,ingrowth and osteogenic differentiation of human bone marrowderived stromal *** particular cells cultured on PCM-2 exhibited a significantly higher expression of osteogenesis-related *** three-layered membranes successfully supported new bone formation inside a critical-size cranial defect in rats,with PCM-3 being the most *** membranes developed here are promising candidates for guided bone regeneration applications.

关键词： bone regeneration poly(caprolactone),mineralized collagen,electrospinning artificial periosteum

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SFRP4 expression correlates with epithelial mesenchymal transitionlinked genes and poor overall survival in colon cancer patients

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World Journal of Gastrointestinal Oncology 2019年第8期11卷 589-598页

作者： Landry E Nfonsam Jana Jandova hunter C Jecius pamela N Omesiete Valentine N Nfonsam Department of Genetics Children’s Hospital of Eastern OntarioOttawaOntario K1H 8L1Canada Department of Surgery University of ArizonaTucsonAZ 85724United States

BACKGROUND Colon cancer is among the most commonly diagnosed cancers in the United States with an estimated 97220 new cases expected by the end of *** affects 1.2 million people around the world and is responsible for about 0.6 million deaths every *** decline in overall incidence and mortality over the past 30 years,there continues to be an alarming rise in early-onset colon cancer cases(he disease and tend to have poor *** previously showed that the WNT“gatekeeper”gene,secreted frizzled-related protein 4(SFRP4),is over-expressed in early-onset colon ***4 is speculated to play an essential role in cancer by inhibiting the epithelial mesenchymal transition(EMT).AIM To investigate the correlation between SFRP4 expression and EMT-linked genes in colon cancer and how it affects patient *** SFRP4 expression relative to that of EMT-linked genes and survival analysis were performed using the University of California Santa Cruz Cancer Browser *** SFRP4 was found to be co-expressed with the EMT-linked markers CDh2,FN1,VIM,TWIST1,TWIST2,SNAI1,SNAI2,ZEB1,ZEB2,POSTN,MMP2,MMP7,MMP9,and ***4 expression negatively correlated with the EMTlinked suppressors CLDN4,CLDN7,TJP3,MUC1,and *** expression of SFRP4 and the EMT-linked markers was higher in mesenchymal-like samples compared to epithelial-like samples which potentially implicates SFRP4-EMT mechanism in colon ***,patients overexpressing SFRP4 presented with poor overall survival(P=0.0293).CONCLUSION Considering the implication of SFRP4 in early-onset colon cancer,particularly in the context of EMT,tumor metastasis,and invasion,and the effect of increased expression on colon cancer patient survival,SFRP4 might be a potential biomarker for early-onset colon cancer that could be targeted for diagnosis and/or disease therapy.

关键词： Secreted frizzled-related protein 4 Epithelial mesenchymal transition Colon cancer Survival

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Porcine model characterizing various parameters assessing the outcome after acetaminophen intoxication induced acute liver failure

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World Journal of Gastroenterology 2017年第9期23卷 1576-1585页

作者： Karolin Thiel Wilfried Klingert Kathrin Klingert Matthias h Morgalla Martin U Schuhmann pamela Leckie Yalda Sharifi Nathan A Davies Rajiv Jalan Andreas Peter Christian Grasshoff Alfred Konigsrainer Martin Schenk Christian Thiel Department of General Visceral and Transplant SurgeryTuebingen University Hospital Department of Anaesthesiology Tuebingen University Hospital Department of Neurosurgery Tuebingen University Hospital Institute for Liver and Digestive health University College London Division of Endocrinology DiabetologyAngiologyNephrologyPathobiochemistry and Clinical ChemistryDepartment of Internal MedicineTuebingen University Hospital

To investigate the changes of hemodynamic and laboratory parameters during the course of acute liver failure following acetaminophen *** pigs underwent a midline laparotomy following jejunal catheter placement for further acetaminophen intoxication and positioning of a portal vein Doppler flow-probe. Acute liver failure was realized by intrajejunal acetaminophen administration in six animals, two animals were sham operated. All animals were invasively monitored and received standardized intensive care support throughout the study. Portal blood flow, hemodynamic and ventilation parameters were continuously recorded. Laboratory parameters were analysed every eight hours. Liver biopsies were sampled every 24 h following intoxication and upon *** liver failure (ALF) occurred after 28 ± 5 h resulted in multiple organ failure and death despite maximal support after further 21 ± 1 h (study end). Portal blood flow (baseline 1100 ± 156 mL/min) increased to a maximum flow of 1873 ± 175 mL/min at manifestation of ALF, which was significantly elevated (P hrombocyte values (baseline 307 × 103/µL ± 34 × 103/µL) of intoxicated animals declined slowly to values of 145 × 103/µL ± 46 × 103/µL when liver failure occurred. Subsequent appearance of severe thrombocytopenia in liver failure resulted in values of 11 × 103/µL ± 3 × 103/µL preceding fatality within few hours which was significant (P > 0.01).CONCLUSIONDeclining portal blood flow and subsequent severe thrombocytopenia after acetaminophen intoxication precede fatality in a porcine acute liver failure model.

关键词： Acetaminophen intoxication Acute liver failure Portal blood flow Thrombocytopenia Animal model Porcine model

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