Wetland seed banks: implications in vegetation management

Studies were conducted in a wetland of the Mingo National Wildlife Refuge, southeast Missouri. Seed distribution pattern in the top 6 cm soil profile was examined. Soil temperature and water matric potential ((psi)) were monitored as various species emerged on the marsh surface during an artificial drawdown. Seeds of the four dominating species (Echinochloa crusgalli, Eleocharis obtusa, Polygonum hydropiperoides, and Xanthium pensylvanicum) were subjected to a wide range of diurnally fluctuating temperatures on a two-way thermogradient plate, and also to a selected range of (psi) in a greenhouse. Physical analyses of soil included an assessment of shear strength ((tau)) at various levels of (psi);Both quantitative and qualitative changes occurred in the seed bank during the study period. The seed distribution pattern, however, did not change significantly;Temperature regimes of 25-32/15-20(DEGREES)C favored seed germination in Echinochloa, whereas, a (psi) less than -76 kPa was found conducive for the emergence of this species in the field during a drawdown. A bimodal response to (psi) was discernible that may have some survival value. Maintaining soil water contents above the so-called field capacity should encourage a good stand of this species in the field. Seeds of Eleocharis germinated better in 25-29/14-19(DEGREES)C regime. Emergence in the field appeared little affected over a wide range of (psi). However, in the greenhouse, a (psi) below -33 kPa sharply reduced the rate of emergence in this species. Polygonum required a 19-21/8-9(DEGREES)C regime for better germination. Field and greenhouse study revealed the stress tolerance limit of this species to be -10 to -15 kPa (psi). Higher temperatures (27-33/16-20(DEGREES)C) as well as lower (psi) (-33 to -80 kPa) were found to favor germination/emergence of Xanthium;Results suggest that a slow drawdown with prolonged period of keeping the soil water content above the so-called field capacity will facilitate the establishment of a good vegetation cover of species useful to waterfowl

The oral lipid sensor GPR120 is not indispensable for the orosensory detectionof dietary lipids in the mouse

International audienceImplication of the long-chain fatty acid (LCFA) receptor GPR120, also termed free fatty acid receptor 4 (FFAR4), in the taste-guided preference for lipids is a matter of debate. To further unravel the role of GPR120 in the "taste of fat", the present study was conducted on GPR120-null mice and their wild-type littermates. Using a combination of morphological (i.e. immunohistochemical staining of circumvallate papillae - CVP), behavioral (i.e. two-bottle preference tests, licking tests and conditioned taste aversion) and functional studies (i.e. calcium imaging in freshly isolated taste bud cells - TBC), we show that absence of GPR120 in oral cavity was not associated with changes in i) the gross anatomy of CVP, ii) the LCFA-mediated increases in [Ca2+]i, iii) the preference for oily and LCFA solutions and iv) the conditioned avoidance of LCFA solutions. In contrast, the rise in [Ca2+]i triggered by grifolic acid (GA), a specific GPR120 agonist, was dramatically curtailed when GPR120 gene was lacking. Taken together these data demonstrate that activation of lingual GPR120 and preference for fat are disconnected, suggesting that GPR120 expressed in TBC is not absolutely required for the oral fat detection in the mouse

A Model of Insulin Resistance in Mice, Born to Diabetic Pregnancy, Is Associated with Alterations of Transcription-Related Genes in Pancreas and Epididymal Adipose Tissue

Objective. This study is conducted on a model of insulin-resistant (IR) mice born to dams which were rendered diabetic by the administration of streptozotocin. Methods. Adult IR and control offspring were selected and we determined the mRNA expression of transcription factors known to modulate pancreatic and adipose tissue activities and inflammation. Results. We observed that serum insulin increased, and the mRNA of insulin gene transcription factors, Pdx-1, Nkx6.1 and Maf-A, were upregulated in IR mice pancreas. Besides, their pancreatic functional capacity seemed to be exhausted as evidenced by low expression of pancreatic Glut2 and glucokinase mRNA. Though IR offspring exhibited reduced epididymal adipose tissue, their adipocytes seemed to be differentiated into macrophage-like cells, as they exhibited upregulated CD14 and CD68 antigens, generally expressed by macrophages. However, there was no peripheral macrophages infiltration into epididymal adipose tissue, as the expression of F4/80, a true macrophage marker, was undetectable. Furthermore, the expression of IL-6, TNF-α and TLR-2, key players of insulin resistance, was upregulated in the adipose tissue of IR offspring. Conclusion. Insulin resistant state in mice, born to diabetic pregnancy, alters the expression of function-related genes in pancreas and epididymal adipose tissue and these offspring are prone to develop metabolic syndrome

Implication de la signalisation calcique et des MAP kinases dans la perception gustative lipidique

Dans ce travail, nous démontrons que STIM1, un senseur calcique activé par la déplétion du Ca2+ intracellulaire du réticulum endoplasmique, est indispensable pour la signalisation calcique et la préférence oro-sensorielle du gras. Nous observons que l'acide linoléique (LA), en activant les phospholipases A2 via CD36, produit de l acide arachidonique (AA) et de la lyso-phosphatidylcholine (lyso-PC). Cette activation déclenche un influx calcique dans les cellules CD36-positives, et induit la production du facteur CIF (Ca2+ Influx Factor). CIF, AA et lyso-PC exercent différentes actions sur l'ouverture des canaux SOC (Stored Operated Calcium Channel) constitués de protéines Orai et contrôlés par STIM1. Par ailleurs, les souris au phénotype Stim1-/- perdent la préférence spontanée pour les lipides et la libération de la sérotonine à partir des cellules gustatives dans le milieu extracellulaire chez les animaux sauvages. Nous demontrons aussi que la signalisation calcique médiée via CD36 est doublement modulée lors de l obésité. L augmentation de la [Ca2+]i dans les cellules gustatives observée chez le Psammomys obesus, un modèle d obésité nutritionelle, est fortement diminuée chez les souris rendues obèses par un regime hyperlipidique. Nous avons constaté également que l interaction de LA avec le CD36 induit l activation des MAP Kinases de la voie MEK1/2/ERK1/2/Elk-1 qui est non seulement à l origine de l activation des aires cérébrales telles que le NTS, le noyau arqué, l hippocampe mais aussi indispensable pour la préférence spontanée pour les lipides alimentaires. Nos résultats suggèrent pour la prémière fois, que la voie ERK1/2 des MAPK et la signalisation calcique lipidique controlée par STIM1 sont impliquées dans la perception oro-gustative des lipidesIn this work, we demonstrate that stromal interaction molecule 1 (STIM1), a sensor of Ca2+ depletion in the endoplasmic reticulum, mediates fatty acid induced Ca2+ signaling in the mouse tongue and fat preference. We showed that linoleic acid (LA) induced the production of arachidonic acid (AA) and lysophosphatidylcholine (Lyso-PC) by activating multiple phospholipase A2 isoforms via CD36. This activation triggered Ca2+ influx in lingual CD36-positive taste bud cells (TBCs) purified from mouse CVP. LA also induced the production of Ca2+ influx factor (CIF). STIM1 was found to regulate LA-induced CIF production and the opening of store-operated Ca2+ (SOC) channels. Furthermore, CD36-positive TBCs from Stim1 / mice failed to release serotonin, and Stim1 / mice lost the spontaneous preference for fat that was observed in wild-type animals. We also demonstrate that the calcium-mediated signaling via CD36 is doubly modulated in obesity. The increase in [Ca2+]i in taste bud cells observed in Psammomys obesus, a model of nutritional obesity is strongly reduced in diet-induced obese (DIO) mice. We also found that the interaction of LA with CD36 induces activation of MAP Kinases MEK1/2/ERK1/2/Elk-1 pathway that is not only responsible for the activation of NTS, arcuate nucleus, and the hippocampus in the brain but also essential for the spontaneous preference for fat food. Our results suggest for the first time, that ERK1/2 MAPK pathway and lipid-induced calcium signaling controlled by STIM1 are involved in oro-gustatory perception of dietary lipidsDIJON-BU Doc.électronique (212319901) / SudocSudocFranceF

Rôle du récepteur nucléaire d'activation et de prolifération des péroxysomes (PPAR-alpha) dans la modulation de l'inflammation et l'activation des cellules T

Notre étude a montré l implication de la déficience de PPARa dans la modulation de latranscription des gènes de l insuline et de l inflammation des adipocytes chez les sourisadultes C57BL/6J (WT) et PPARa-null. A jeun, les souris PPARa-null sont hypoglycémiquespar rapport aux animaux témoins WT. La concentration en insuline et l expression de sesARNm pancréatiques, par rapport aux animaux témoins, sont diminuées chez les sourisPPARa-null, suggérant que la suppression du gène de PPARa contribuait à la faibletranscription de ces gènes. De plus, la suppression du gène de PPARa aboutit à la diminutiondes facteurs de transcription des gènes de l insuline comme Pdx-1, Nkx6.1 et MafA. En outre,la capacité pancréatique fonctionnelle est aussi détériorée par la suppression du gène dePPARa puisque le pancréas des souris PPARa-null exprime de faibles taux de Glut2 et deglucokinase. Les souris PPARa-null expriment des taux élevés d adiponectine et de leptinecomparées aux souris témoins. Dans les tissus adipeux, les souris PPARa-null présentent uneaugmentation de l expression de CD14 et CD68 généralement exprimés par les macrophages.La suppression du gène de PPARa diminue, au niveau des adipocytes, l expression de MCP-1, TNFa, IL-1b, IL-6 et RANTES, alors que l expression de TLR-2 et de TLR-4 (récepteurspro-inflammatoires) était élevée dans les tissus adipeux. Ces résultats suggèrent qu encondition normale, la déficience en PPARa, chez les souris est impliquée dans la modulationde la transcription des gènes de l insuline et le statut inflammatoire du tissu adipeux.En outre, l'invalidation du gène de PPARa dans les cellules T a abouti àl'augmentation de T-bet et la diminution de GATA-3 tant aux niveaux de la protéine que del ARNm. Comme prévu, l acide Docosahexaénoïque (DHA) a exercé non seulement un effetinhibiteur sur la prolifération des cellules T, mais aussi a diminué la sécrétion d IFN-g etstimulé la sécrétion de l IL-4 dans les deux types cellulaires. Le DHA a aussi diminué T-bet etaugmenté GATA-3 tant au niveau de la transcription qu au niveau de la protéine. Quoique lescellules T des souris PPARa-null ont exprimé un plus fort niveau de phosphorylation de p38MAP kinase que les cellules T de WT, le DHA a diminué la phosphorylation des MAPkinases (p38 et ERK1/2) dans tous les deux les types cellulaires. Les inhibiteurspharmacologiques des MAP kinases ont aussi diminué T-bet et augmenté GATA-3 dans lescellules T. Ces résultats démontrent que le DHA, via son action sur les MAP kinases, modulel'expression des facteurs de transcription. Ces résultats expliquent aussi le mécanisme d'actionde cet acide gras sur la différenciation des cellules T dans la maladie et la santéWe assessed, in this study, the effects of PPARa deficiency on the expression of mRNAencoding for insulin gene transcription factors in pancreatic b-cells along with thoseimplicated in inflammation in adipose tissues. On fasting, the adult PPARa-null mice werehypoglycemic. Serum insulin concentrations and its pancreatic mRNA transcripts weredownregulated in PPARa-null mice, suggesting that PPARa gene deletion contributes to lowinsulin gene transcription. The PPARa gene deletion downregulates the mRNA expression ofinsulin gene transcription factors, i.e., Pdx-1, Nkx6.1 and MafA. Besides, the pancreaticfunction was diminished by PPARa deficiency as PPARa-null mice expressed low pancreaticGlut2 and glucokinase mRNA. PPARa-null mice also expressed high adiponectin and leptinmRNA levels compared to wild type animals. Adipose tissues of PPARa-null mice exhibitedupregulation of CD14 and CD68 mRNA, generally expressed by macrophages. PPAR-a genedeletion downregulates the adipocyte mRNA of certain pro inflammatory agents, like MCP-1,TNF-a, IL-1b, IL-6, and RANTES, though pro-inflammatory TLR-2 and TLR-4 mRNAswere upregulated in the adipose tissues. Our results suggest that PPAR-a deficiency, in mice,is implicated in the modulation of insulin gene transcription and inflammatory status inadipose tissues.The another part of the study was conducted on CD4+ T-cells, isolated from wild type(WT) and PPARa-null mice, in order to assess the mechanismof action of docosahexaenoicacid (DHA), an n-3 fatty acid, in the modulation of two transcription factors, i.e., T-bet andGATA-3, implicated in T-cell differentiation towards, respectively, TH1 and TH2 phenotype.The T-cells from PPARa-null mice secreted higher IFN-g and lower IL-4 concentrations thanWT T-cells. Furthermore, the deletion of PPAR-a gene in T-cells resulted in the upregulationof T-bet and downregulation of GATA-3 both at mRNA and protein levels. DHA exerted notonly an inhibitory effect on T-cell proliferation, but also diminished IFN-g and stimulated IL-4 secretions in both cell types. DHA also downregulated T-bet and upregulated GATA-3 bothat transcription and protein levels. Though the T-cells from PPARa-null mice expressedhigher p38 phosphorylation than WT T-cells, DHA diminished the MAP kinasephosphorylation (p38 and ERK1/2) in both the cell types. The pharmacological inhibitors ofMAP kinases also downregulated T-bet and upregulated GATA-3 in T-cells. Altogether, theseresults demonstrate that DHA, via its action on MAP kinases, modulates the expression oftranscription factors. These results also explain the mechanism of action of this fatty acid onT-cell differentiation in disease and healthDIJON-BU Doc.électronique (212319901) / SudocSudocFranceF

Population size, behavior and threats to Indian Skimmers (<i>Rhynchops albicollis</i>) at their largest known wintering site

Bangladesh hosts most of what is left of Indian Skimmer (Rhynchops albicollis) populations, a globally endangered species. Each October-March from 2015-2020, 21 surveys of nonbreeding birds were made in Nijhum Dweep National Park, Bangladesh. High tide or evening roosts were counted from vantage points whenever a buildup or breakdown of skimmer concentrations was noticed, and site use noted by marking all observations of presence and activity on maps. The largest single count was 3,108 skimmers on 18 February 2020, constituting 30-50% of the known global population. Indian Skimmers mostly occurred in Damar Char West and at the tip of the Majher Char. Throughout the day with incoming tide, skimmers moved between preferred roosting areas to forage in the shallows. We describe a unique group-foraging strategy in which skimmers chase fish from deep water to shallow water along the shoreline. Circling high over the tidal channel, the flock of skimmers dives down in unison to just above the water surface, then spreading like a net towards the shore. Raptors caused disturbances to roosting skimmers, and we observed one instance of predation of a skimmer by a White-bellied Sea Eagle (Haliaeetus leucogaster). Human fishing activities disturbed nearshore foraging and shoreline roosting skimmers. We suggest protecting Damar Char West by regulating human activities to minimize disturbance from December to March

Substrate−-bias driven Sputter deposited β−\beta-phase dominated Tungsten film for Spintronic applications

$\beta$-Tungsten ($\beta$-W), a A15 cubic phase of Tungsten exhibits giant spin hall angle as compared to its bcc-phase $\alpha$-Tungsten ($\alpha$-W), making high quality $\beta$-W film desirable for spin-based application. We report on the substrate bias driven on-demand growth of $\beta$-W film on SiO$_2$ coated silicon (SiO$_2$/Si) using DC sputtering. GIXRD plots and SEM images are used to show a systematic change on the structure and grain size of the deposited films with the application of substrate bias. It is observed that zero bias film are amorphous in nature and changes phase from $\alpha$ to $\beta$ or mixed ($\alpha$ + $\beta$) depending upon the sign and magnitude of the substrate bias. We performed One-Dimensional Power spectrum density of the AFM images which revealed that the pure $\beta$-W film grown at a positive bias of +50V has the minimum roughness as compared to films grown at different substrate bias. We further confirm the metallic surface homogeneity using the room temperature STM. Our results shows that the substrate bias which controls the energy of the deposited atom, is a crucial parameter for an on demand growth of $\beta$-W, an important material for spintronic applications.Comment: 5 pages, 4 figure

Mycobacterium tuberculosis secretory proteins downregulate T cell activation by interfering with proximal and downstream T cell signalling events

BACKGROUND: Mycobacterium tuberculosis (M. tuberculosis) modulates host immune response, mainly T cell responses for its own survival leading to disease or latent infection. The molecules and mechanisms utilized to accomplish immune subversion by M. tuberculosis are not fully understood. Understanding the molecular mechanism of T cell response to M. tuberculosis is important for development of efficacious vaccine against TB. METHODS: Here, we investigated effect of M. tuberculosis antigens Ag85A and ESAT-6 on T cell signalling events in CD3/CD28 induced Peripheral blood mononuclear cells (PBMCs) of PPD+ve healthy individuals and pulmonary TB patients. We studied CD3 induced intracellular calcium mobilization in PBMCs of healthy individuals and TB patients by spectrofluorimetry, CD3 and CD28 induced activation of mitogen activated protein kinases (MAPKs) in PBMCs of healthy individuals and TB patients by western blotting and binding of transcription factors NFAT and NFκB by Electrophorectic mobility shift assay (EMSA). RESULTS: We observed CD3 triggered modulations in free intracellular calcium concentrations in PPD+ve healthy individuals and pulmonary TB patients after the treatment of M. tuberculosis antigens. As regards the downstream signalling events, phosphorylation of MAPKs, Extracellular signal-regulated kinase 1 and 2 (ERK1/2) and p38 was curtailed by M. tuberculosis antigens in TB patients whereas, in PPD+ve healthy individuals only ERK1/2 phosphorylation was inhibited. Besides, the terminal signalling events like binding of transcription factors NFAT and NFκB was also altered by M. tuberculosis antigens. Altogether, our results suggest that M. tuberculosis antigens, specifically ESAT-6, interfere with TCR/CD28-induced upstream as well as downstream signalling events which might be responsible for defective IL-2 production which further contributed in T-cell unresponsiveness, implicated in the progression of disease. CONCLUSION: To the best of our knowledge, this is the first study to investigate effect of Ag85A and ESAT-6 on TCR- and TCR/CD28- induced upstream and downstream signalling events of T-cell activation in TB patients. This study showed the effect of secretory antigens of M. tuberculosis in the modulation of T cell signalling pathways. This inflection is accomplished by altering the proximal and distal events of signalling cascade which could be involved in T-cell dysfunctioning during the progression of the disease. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12865-015-0128-6) contains supplementary material, which is available to authorized users

Groundwater investigations in the Hattar Industrial Estate and its vicinity, Haripur district, Pakistan: An integrated approach

The Hattar industrial estate in the Haripur district, Khyber Pakhtunkhwa (KPK), Pakistan, is investigated for the groundwater potential and aquifer vulnerability using vertical electrical sounding (VES), borehole logs and geochemical data. A total of eight VES points were obtained in the Haripur region using Schlumberger configuration. The interpreted VES models are further constrained by four borehole logs to delineate comprehensive information of the thin lithological layers, subsurface layers configuration, and spatial extent in the area. A quantitative interpretation based on the VES and the borehole data suggests six main subsurface layers; (i) soil cover, (ii) gravel, (iii) clay, (iv) clay with gravel, (v) silty-clay, and (vi) sand with boulder in the study area. A fence diagram is also generated to provide a detailed paleo-depositional model of the subsurface layers. A number of productive groundwater zones are identified across the study area. The interpreted VES data is utilized to compute aquifer thickness, longitudinal conductance, longitudinal resistivity, and transverse resistance within the study area. The lateral extent and protective capacity for the aquifer were inferred from these measurements. The aquifer thickness is relatively low in the central and eastern part ranging from 10 m to 11 m. The longitudinal conductance map shows values greater than 2 mhos from central region to north. This is an indicative of moderate to good protective capacity for the aquifer and is less vulnerable to infiltration of Hattar industrial polluted fluid. However, the values less than 0.19 mhos in the southwest and east are indicative of weak protective capacity with risk of contamination. The geochemical analysis of the surface and subsurface water is carried out at eleven locations to identify the water quality within the study area. The chemical analysis of the water shows presence of the high concentration of Magnesium, bi-carbonate, and Chlorine away from the World Health Organization (WHO) standard

Convalescent plasma in patients admitted to hospital with COVID-19 (RECOVERY): a randomised controlled, open-label, platform trial

SummaryBackground Azithromycin has been proposed as a treatment for COVID-19 on the basis of its immunomodulatoryactions. We aimed to evaluate the safety and efficacy of azithromycin in patients admitted to hospital with COVID-19.Methods In this randomised, controlled, open-label, adaptive platform trial (Randomised Evaluation of COVID-19Therapy [RECOVERY]), several possible treatments were compared with usual care in patients admitted to hospitalwith COVID-19 in the UK. The trial is underway at 176 hospitals in the UK. Eligible and consenting patients wererandomly allocated to either usual standard of care alone or usual standard of care plus azithromycin 500 mg once perday by mouth or intravenously for 10 days or until discharge (or allocation to one of the other RECOVERY treatmentgroups). Patients were assigned via web-based simple (unstratified) randomisation with allocation concealment andwere twice as likely to be randomly assigned to usual care than to any of the active treatment groups. Participants andlocal study staff were not masked to the allocated treatment, but all others involved in the trial were masked to theoutcome data during the trial. The primary outcome was 28-day all-cause mortality, assessed in the intention-to-treatpopulation. The trial is registered with ISRCTN, 50189673, and ClinicalTrials.gov, NCT04381936.Findings Between April 7 and Nov 27, 2020, of 16 442 patients enrolled in the RECOVERY trial, 9433 (57%) wereeligible and 7763 were included in the assessment of azithromycin. The mean age of these study participants was65·3 years (SD 15·7) and approximately a third were women (2944 [38%] of 7763). 2582 patients were randomlyallocated to receive azithromycin and 5181 patients were randomly allocated to usual care alone. Overall,561 (22%) patients allocated to azithromycin and 1162 (22%) patients allocated to usual care died within 28 days(rate ratio 0·97, 95% CI 0·87–1·07; p=0·50). No significant difference was seen in duration of hospital stay (median10 days [IQR 5 to >28] vs 11 days [5 to >28]) or the proportion of patients discharged from hospital alive within 28 days(rate ratio 1·04, 95% CI 0·98–1·10; p=0·19). Among those not on invasive mechanical ventilation at baseline, nosignificant difference was seen in the proportion meeting the composite endpoint of invasive mechanical ventilationor death (risk ratio 0·95, 95% CI 0·87–1·03; p=0·24).Interpretation In patients admitted to hospital with COVID-19, azithromycin did not improve survival or otherprespecified clinical outcomes. Azithromycin use in patients admitted to hospital with COVID-19 should be restrictedto patients in whom there is a clear antimicrobial indication