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1.
Proc Natl Acad Sci U S A ; 118(26)2021 06 29.
Artículo en Inglés | MEDLINE | ID: mdl-34155114

RESUMEN

Many latitudinal insect migrants including agricultural pests, disease vectors, and beneficial species show huge fluctuations in the year-to-year abundance of spring immigrants reaching temperate zones. It is widely believed that this variation is driven by climatic conditions in the winter-breeding regions, but evidence is lacking. We identified the environmental drivers of the annual population dynamics of a cosmopolitan migrant butterfly (the painted lady Vanessa cardui) using a combination of long-term monitoring and climate and atmospheric data within the western part of its Afro-Palearctic migratory range. Our population models show that a combination of high winter NDVI (normalized difference vegetation index) in the Savanna/Sahel of sub-Saharan Africa, high spring NDVI in the Maghreb of North Africa, and frequent favorably directed tailwinds during migration periods are the three most important drivers of the size of the immigration to western Europe, while our atmospheric trajectory simulations demonstrate regular opportunities for wind-borne trans-Saharan movements. The effects of sub-Saharan vegetative productivity and wind conditions confirm that painted lady populations on either side of the Sahara are linked by regular mass migrations, making this the longest annual insect migration circuit so far known. Our results provide a quantification of the environmental drivers of large annual population fluctuations of an insect migrant and hold much promise for predicting invasions of migrant insect pests, disease vectors, and beneficial species.


Asunto(s)
Migración Animal/fisiología , Mariposas Diurnas/fisiología , Ambiente , África del Norte , Animales , Simulación por Computador , Clima Desértico , Europa (Continente) , Geografía , Región Mediterránea , Densidad de Población , Dinámica Poblacional , Estaciones del Año , Viento
2.
Glob Chang Biol ; 29(5): 1282-1295, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36462155

RESUMEN

There is mounting evidence that terrestrial arthropods are declining rapidly in many areas of the world. It is unclear whether freshwater invertebrates, which are key providers of ecosystem services, are also declining. We addressed this question by analysing a long-term dataset of macroinvertebrate abundance collected from 2002 to 2019 across 5009 sampling sites in English rivers. Patterns varied markedly across taxonomic groups. Within trophic groups we detected increases in the abundance of carnivores by 19% and herbivores by 14.8%, while we estimated decomposers have declined by 21.7% in abundance since 2002. We also found heterogeneity in trends across rivers belonging to different typologies based on geological dominance and catchment altitude, with organic lowland rivers having generally higher rates of increase in abundance across taxa and trophic groups, with siliceous lowland rivers having the most declines. Our results reveal a complex picture of change in freshwater macroinvertebrate abundance between taxonomic groups, trophic levels and river typologies. Our analysis helps with identifying priority regions for action on potential environmental stressors where we discover macroinvertebrate abundance declines.


Asunto(s)
Ecosistema , Ríos , Animales , Biodiversidad , Monitoreo del Ambiente/métodos , Invertebrados
3.
Glob Chang Biol ; 29(12): 3271-3284, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36924241

RESUMEN

At large scales, the mechanisms underpinning stability in natural communities may vary in importance due to changes in species composition, mean abundance, and species richness. Here we link species characteristics (niche positions) and community characteristics (richness and abundance) to evaluate the importance of stability mechanisms in 156 butterfly communities monitored across three European countries and spanning five bioclimatic regions. We construct niche-based hierarchical structural Bayesian models to explain first differences in abundance, population stability, and species richness between the countries, and then explore how these factors impact community stability both directly and indirectly (via synchrony and population stability). Species richness was partially explained by the position of a site relative to the niches of the species pool, and species near the centre of their niche had higher average population stability. The differences in mean abundance, population stability, and species richness then influenced how much variation in community stability they explained across the countries. We found, using variance partitioning, that community stability in Finnish communities was most influenced by community abundance, whereas this aspect was unimportant in Spain with species synchrony explaining most variation; the UK was somewhat intermediate with both factors explaining variation. Across all countries, the diversity-stability relationship was indirect with species richness reducing synchrony which increased community stability, with no direct effects of species richness. Our results suggest that in natural communities, biogeographical variation observed in key drivers of stability, such as population abundance and species richness, leads to community stability being limited by different factors and that this can partially be explained due to the niche characteristics of the European butterfly assemblage.


Asunto(s)
Mariposas Diurnas , Ecosistema , Animales , Biodiversidad , Teorema de Bayes , Europa (Continente)
4.
J Immunol ; 207(11): 2813-2827, 2021 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-34740958

RESUMEN

Hypoxia-inducible factor-1α (HIF-1α) is an important regulator of glucose metabolism and inflammatory cytokine production in innate immune responses. Viruses modulate HIF-1α to support viral replication and the survival of infected cells, but it is unclear if this transcription factor also plays an important role in regulating antiviral immune responses. In this study, we found that short and long dsRNA differentially engage TLR3, inducing distinct levels of proinflammatory cytokine production (TNF-α and IL-6) in bone marrow-derived macrophages from C57BL/6 mice. These responses are associated with differential accumulation of HIF-1α, which augments NF-κB activation. Unlike TLR4 responses, increased HIF-1α following TLR3 engagement is not associated with significant alterations in glycolytic activity and was more pronounced in low glucose conditions. We also show that the mechanisms supporting HIF-1α stabilization may differ following stimulation with short versus long dsRNA and that pyruvate kinase M2 and mitochondrial reactive oxygen species play a central role in these processes. Collectively, this work suggests that HIF-1α may fine-tune proinflammatory cytokine production during early antiviral immune responses, particularly when there is limited glucose availability or under other conditions of stress. Our findings also suggest we may be able to regulate the magnitude of proinflammatory cytokine production during antiviral responses by targeting proteins or molecules that contribute to HIF-1α stabilization.


Asunto(s)
Citocinas/biosíntesis , Glucosa/inmunología , Subunidad alfa del Factor 1 Inducible por Hipoxia/inmunología , Macrófagos/inmunología , Ácidos Nucleicos/inmunología , Receptor Toll-Like 3/inmunología , Animales , Células Cultivadas , Ratones , Ratones Endogámicos C57BL , Especies Reactivas de Oxígeno/inmunología
5.
Catheter Cardiovasc Interv ; 100(7): 1252-1260, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36321629

RESUMEN

OBJECTIVES: To determine safety and feasibility of ex-situ coronary angiography. BACKGROUND: To cater for the perpetually growing demand for heart donors, interest in donation following circulatory death (DCD) has been rekindled. Further pursuit of donor pool expansion has led to eligibility extension to "marginal" donors who are at higher risk of coronary artery disease (CAD). Excluding CAD in potentially eligible DCD donors, for whom ante-mortem angiography is commonly not permitted, is therefore challenging. Ex-situ coronary angiography serves as an ethical and feasible diagnostic tool to assess for preclusive CAD. METHODS: We undertook a systematic review of the published literature and institutional retrospective review of case experience with ex-situ coronary angiography of donor hearts, supported by a portable organ care system. RESULTS: Combined literature and institutional case review yielded nine total cases of ex-situ coronary angiography of donor human hearts plus one experimental porcine model. Of the eight cases of ex-situ coronary angiography performed at our institute, all were conducted without complication or injury to the allograft. Two thirds of reported human cases have proceeded to successful transplantation. CONCLUSIONS: Diagnostic coronary angiography of the ex-situ beating donor heart is safe, feasible, and demonstrates novel clinical utility in mitigating subsequent transplantation of unsuitable allografts. In the setting of suspected coronary atherosclerosis of the donor heart, which may preclude favorable transplantation outcomes, ex-situ coronary angiography should be considered at eligible transplant centers.


Asunto(s)
Trasplante de Corazón , Donantes de Tejidos , Humanos , Porcinos , Animales , Trasplante de Corazón/efectos adversos , Angiografía Coronaria/efectos adversos , Resultado del Tratamiento , Estudios Retrospectivos
6.
Am J Emerg Med ; 55: 76-81, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35287091

RESUMEN

STUDY OBJECTIVES: The objective of this study was to compare the combination of intramuscular (IM) droperidol/midazolam to haloperidol/lorazepam regarding time to sedation in patients with acute undifferentiated agitation in the emergency department (ED). METHODS: This was a prospective, unblinded observational study in the ED of a university teaching hospital. Subjects with acute undifferentiated agitation refractory to verbal de-escalation were assigned to receive a combination of either haloperidol 5 mg/lorazepam 2 mg or droperidol 5 mg/midazolam 5 mg IM. The primary outcome was the proportion of patients adequately sedated at 10 min defined as ED Sedation Assessment Tool (SAT) score of 0 or less. Secondary outcomes included change in ED SAT score at 5, 15, 30, and 60 min, the need for oxygen supplementation, and the need for airway intervention. RESULTS: A total of 86 patients were enrolled in the study, with 43 patients receiving droperidol/midazolam and 43 patients receiving haloperidol/lorazepam. Ten minutes after receiving medication, 51.2% of patients in the droperidol/midazolam group were adequately sedated compared to 7% of patients in the haloperidol/lorazepam group (OR: 14; 95% CI: 3.7, 52.1). Median time to adequate sedation was 10 min for the droperidol/midazolam group and 30 min for the haloperidol/lorazepam group. Eleven patients (25.6%) in the droperidol/midazolam group received oxygen supplementation compared to four patients (9.3%) in the haloperidol/lorazepam group. No study patients experienced extrapyramidal symptoms or required endotracheal intubation. CONCLUSION: Intramuscular droperidol/midazolam was superior to intramuscular haloperidol/lorazepam in achieving adequate sedation at 10 min. Patients in the droperidol/midazolam arm may be more likely to receive oxygen supplementation than those in the haloperidol/lorazepam arm.


Asunto(s)
Droperidol , Haloperidol , Lorazepam , Midazolam , Agitación Psicomotora , Antipsicóticos/uso terapéutico , Droperidol/uso terapéutico , Servicio de Urgencia en Hospital , Haloperidol/uso terapéutico , Humanos , Lorazepam/uso terapéutico , Midazolam/uso terapéutico , Estudios Prospectivos , Agitación Psicomotora/tratamiento farmacológico
7.
Nucleic Acids Res ; 48(16): 8815-8827, 2020 09 18.
Artículo en Inglés | MEDLINE | ID: mdl-32556263

RESUMEN

Bacteria have evolved defence mechanisms against bacteriophages. Restriction-modification systems provide innate immunity by degrading invading DNAs that lack proper methylation. CRISPR-Cas systems provide adaptive immunity by sampling the genome of past invaders and cutting the DNA of closely related DNA molecules. These barriers also restrict horizontal gene transfer mediated by conjugative plasmids. IncC conjugative plasmids are important contributors to the global dissemination of multidrug resistance among pathogenic bacteria infecting animals and humans. Here, we show that IncC conjugative plasmids are highly resilient to host defence systems during entry into a new host by conjugation. Using a TnSeq strategy, we uncover a conserved operon containing five genes (vcrx089-vcrx093) that confer a novel host defence evasion (hde) phenotype. We show that vcrx089-vcrx090 promote resistance against type I restriction-modification, whereas vcrx091-vcxr093 promote CRISPR-Cas evasion by repairing double-strand DNA breaks via recombination between short sequence repeats. vcrx091, vcrx092 and vcrx093 encode a single-strand binding protein, and a single-strand annealing recombinase and double-strand exonuclease related to Redß and λExo of bacteriophage λ, respectively. Homologous genes of the integrative and conjugative element R391 also provide CRISPR-Cas evasion. Hence, the conserved hde operon considerably broadens the host range of large families of mobile elements spreading multidrug resistance.


Asunto(s)
Sistemas CRISPR-Cas , Conjugación Genética , Enzimas de Restricción-Modificación del ADN/genética , Escherichia coli/genética , Plásmidos/genética , Vibrio cholerae/genética , Bacteriófago lambda/genética , Transferencia de Gen Horizontal , Operón
8.
Heart Lung Circ ; 31(11): e135-e139, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35985946

RESUMEN

Peripheral vascular assessment is important in pre-procedural planning for transcatheter aortic valve implantation (TAVI). While alternative vascular access sites have been used in patients with hostile iliofemoral anatomy, femoral access has been established as the superior access method for procedural outcomes. Intravascular lithotripsy (IVL) can facilitate transfemoral access for TAVI in patients with calcific stenoses of the iliofemoral arteries. This How-To-Do-It article describes the procedural planning and methods for performing IVL in these patients.


Asunto(s)
Estenosis de la Válvula Aórtica , Litotricia , Reemplazo de la Válvula Aórtica Transcatéter , Humanos , Reemplazo de la Válvula Aórtica Transcatéter/métodos , Estenosis de la Válvula Aórtica/diagnóstico , Estenosis de la Válvula Aórtica/cirugía , Resultado del Tratamiento , Arteria Femoral/cirugía , Válvula Aórtica/diagnóstico por imagen , Válvula Aórtica/cirugía
9.
J Med Virol ; 93(9): 5333-5338, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33851739

RESUMEN

The accurate laboratory detection of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a crucial element in the fight against coronavirus disease 2019 (COVID-19). Reverse transcription-polymerase chain reaction testing on combined oral and nasopharyngeal swab (ONPS) suffers from several limitations, including the need for qualified personnel, the discomfort caused by invasive nasopharyngeal sample collection, and the possibility of swab and transport media shortage. Testing on saliva would represent an advancement. The aim of this study was to compare the concordance between saliva samples and ONPS for the detection of SARS-CoV-2 on various commercial and laboratory-developed tests (LDT). Individuals were recruited from eight institutions in Quebec, Canada, if they had SARS-CoV-2 RNA detected on a recently collected ONPS, and accepted to provide another ONPS, paired with saliva. Assays available in the different laboratories (Abbott RealTime SARS-CoV-2, Cobas® SARS-CoV-2, Simplexa™ COVID-19 Direct, Allplex™ 2019-nCoV, RIDA®GENE SARS-CoV-2, and an LDT preceded by three different extraction methods) were used to determine the concordance between saliva and ONPS results. Overall, 320 tests were run from a total of 125 saliva and ONPS sample pairs. All assays yielded similar sensitivity when saliva was compared to ONPS, with the exception of one LDT (67% vs. 93%). The mean difference in cycle threshold (∆C t ) was generally (but not significantly) in favor of the ONPS for all nucleic acid amplification tests. The maximum mean ∆​​​​​C t was 2.0, while individual ∆C t varied importantly from -17.5 to 12.4. Saliva seems to be associated with sensitivity similar to ONPS for the detection of SARS-CoV-2 by various assays.


Asunto(s)
Prueba de Ácido Nucleico para COVID-19/normas , COVID-19/diagnóstico , Pruebas Diagnósticas de Rutina/normas , ARN Viral/genética , SARS-CoV-2/genética , COVID-19/epidemiología , COVID-19/virología , Prueba de Ácido Nucleico para COVID-19/instrumentación , Prueba de Ácido Nucleico para COVID-19/métodos , Pruebas Diagnósticas de Rutina/instrumentación , Pruebas Diagnósticas de Rutina/métodos , Humanos , Boca/virología , Nasofaringe/virología , Quebec/epidemiología , Saliva/virología , Sensibilidad y Especificidad , Manejo de Especímenes/normas
10.
Med J Aust ; 215(2): 89-93, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34218432

RESUMEN

A patent foramen ovale (PFO) is an interatrial shunt, with a prevalence of 20-34% in the general population. While most people do not have secondary manifestations of a PFO, some reported sequelae include ischaemic stroke, migraine, platypnoea-orthodeoxia syndrome and decompression illness. Furthermore, in some cases, PFO closure should be considered for patients before neurosurgery and for patients with concomitant carcinoid syndrome. Recent trials support PFO closure for ischaemic stroke patients with high risk PFOs and absence of other identified stroke mechanisms. While PFOs can be associated with migraine with auras, with some patients reporting symptomatic improvement after closure, the evidence from randomised controlled trials is less clear in supporting the use of PFO closure for migraine treatment. PFO closure for other indications such as platypnoea-orthodeoxia syndrome, decompression illness and paradoxical embolism are based largely on case series with good clinical outcomes. PFO closure can be performed as a day surgical intervention with high procedural success and low risk of complications.


Asunto(s)
Cateterismo Cardíaco , Disnea/etiología , Foramen Oval Permeable/complicaciones , Accidente Cerebrovascular Isquémico/etiología , Trastornos Migrañosos/etiología , Disnea/epidemiología , Disnea/cirugía , Foramen Oval Permeable/epidemiología , Foramen Oval Permeable/cirugía , Humanos , Accidente Cerebrovascular Isquémico/epidemiología , Accidente Cerebrovascular Isquémico/cirugía , Trastornos Migrañosos/epidemiología , Trastornos Migrañosos/cirugía , Prevalencia , Resultado del Tratamiento
12.
J Shoulder Elbow Surg ; 30(4): 819-825, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32763382

RESUMEN

BACKGROUND: Proximal humerus fractures are the third most common osteoporosis defining injury in the United States, yet operative fixation of these injuries remains technically challenging. Although several modifiable and nonmodifiable risk factors are correlated with failure of proximal humerus fixation, no study has investigated whether failure to restore glenohumeral offset plays a part in fixation failure. The goals of this study are: (1) to determine if lateral glenohumeral offset (LGHO) and humeral head diameter (HHD) can be measured radiographically with accuracy between observers, (2) to observe whether there is a correlation between failure to operatively restore an anatomic LGHO:HHD ratio and failure of fixation, and (3) if there is a correlation, can any recommendations be made in regard to the ideal LGHO:HHD ratio. METHODS: Retrospective review found 183 patients meeting inclusion criteria who underwent operative fixation for proximal humerus fractures between 2005 and 2018. Patients suffering construct failure requiring reoperation were compared with clinically successful surgeries on the basis of age, sex, fracture morphology, head-shaft angle, smoking history, presence or absence of a calcar screw, and LGHO:HHD ratio. The groups were compared using a combination of Student t-tests, χ2, and bivariate and multivariate logistic regression analyses where appropriate. The Student t-test and intraclass correlation coefficient were both used to assess interobserver reliability. RESULTS: We found that LGHO and HHD can be measured by independent observers accurately (intraclass correlation coefficient = 0.80, 95% confidence interval: 0.65-0.89). Patients suffering implant failure had a significantly lower LGHO:HHD ratios compared with those who did not (0.94 vs. 1.03, P ≤ .001). The LGHO:HHD ratio was an independent predictor of implant failure even after controlling for other potential risk factors. Patients with an LGHO:HHD of 1.0 or above have a <10% chance of failure compared with a 20% risk with a ratio of 0.9 and a 40% risk at 0.8. CONCLUSION: We found the LGHO:HHD ratio to be an independent predictor for construct failure after plate and screw fixation of proximal humerus fractures. Efforts should be made to restore an anatomic ratio of at least 1.0 to minimize the risk of failure.


Asunto(s)
Fijación Interna de Fracturas/efectos adversos , Reducción Abierta/efectos adversos , Fracturas del Hombro , Articulación del Hombro , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Placas Óseas , Tornillos Óseos , Femenino , Fijación Interna de Fracturas/instrumentación , Fijación Interna de Fracturas/métodos , Humanos , Cabeza Humeral/diagnóstico por imagen , Cabeza Humeral/cirugía , Masculino , Persona de Mediana Edad , Reducción Abierta/métodos , Reproducibilidad de los Resultados , Estudios Retrospectivos , Fracturas del Hombro/diagnóstico por imagen , Fracturas del Hombro/cirugía , Articulación del Hombro/diagnóstico por imagen , Articulación del Hombro/cirugía , Adulto Joven
13.
Glob Chang Biol ; 26(2): 971-988, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31840377

RESUMEN

Major environmental changes in the history of life on Earth have given rise to novel habitats, which gradually accumulate species. Human-induced change is no exception, yet the rules governing species accumulation in anthropogenic habitats are not fully developed. Here we propose that nonnative plants introduced to Great Britain may function as analogues of novel anthropogenic habitats for insects and mites, analysing a combination of local-scale experimental plot data and geographic-scale data contained within the Great Britain Database of Insects and their Food Plants. We find that novel plant habitats accumulate the greatest diversity of insect taxa when they are widespread and show some resemblance to plant habitats which have been present historically (based on the relatedness between native and nonnative plant species), with insect generalists colonizing from a wider range of sources. Despite reduced per-plant diversity, nonnative plants can support distinctive insect communities, sometimes including insect taxa that are otherwise rare or absent. Thus, novel plant habitats may contribute to, and potentially maintain, broader-scale (assemblage) diversity in regions that contain mixtures of long-standing and novel plant habitats.


Asunto(s)
Ecosistema , Ácaros , Animales , Biodiversidad , Humanos , Insectos , Plantas , Reino Unido
14.
RNA Biol ; 17(6): 755-764, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32050839

RESUMEN

Small interfering RNA (siRNA) is a critical loss-of-function tool for elucidating the role of genes in biomedical studies. The effective use of siRNA needs transfection technology that delivers siRNA into the correct location of target cells, especially those which are extremely difficult to transfect. Macrophages, which play an important role in the pathogenesis of many diseases, are known to be extremely hard to transfect. Thus, to elucidate the functions of genes in human macrophage biology, it is essential to devise technology for efficient siRNA transfection. However, a fast and efficient method for siRNA transfection in primary human macrophages has not been reported. The siRNA transfection is a tug-of-war between transfection rate and cytotoxicity. A higher transfection rate is generally accompanied with increased cytotoxicity, therefore, choosing a transfection reagent that limits cell death while maintain a desirable transfection rate is important. In this study, we employed auto-analysis function of the IncuCyte® to devise a fast and cost-saving technology for efficient transfection of adherent cells and particularly human macrophages. We show that DharmaFECT3 transfection reagent from Dharmacon was the most efficient in transfecting primary human monocyte-derived macrophages and PMA-differentiated U937 cells, whereas other transfection reagents tested were cytotoxic. This method exhibited approximately 85% transfection efficiency in human macrophages. Moreover, siRNA silencing of Bax with this technique effectively protected primary human macrophages and PMA-differentiated U937 cells against Resveratrol-induced cell death. In addition, this method inherently takes the balance between transfection rate and cytotoxicity of siRNA transfection reagents into consideration.


Asunto(s)
Apoptosis/efectos de los fármacos , Apoptosis/genética , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , ARN Interferente Pequeño/genética , Resveratrol/farmacología , Proteína X Asociada a bcl-2/genética , Diferenciación Celular/efectos de los fármacos , Diferenciación Celular/genética , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/genética , Células Cultivadas , Dosificación de Gen , Expresión Génica , Humanos , Macrófagos/citología , Transfección
15.
J Biol Chem ; 293(31): 12011-12025, 2018 08 03.
Artículo en Inglés | MEDLINE | ID: mdl-29884769

RESUMEN

Streptococcus suis serotype 2 is an important porcine and human pathogen. Lipoteichoic acid (LTA) from S. suis has been suggested to contribute to its virulence, and absence of d-alanylation from the S. suis LTA is associated with increased susceptibility to cationic antimicrobial peptides. Here, using high-resolution NMR spectroscopy and MS analyses, we characterized the LTA structures from three S. suis serotype 2 strains differing in virulence, sequence type (ST), and geographical origin. Our analyses revealed that these strains possess-in addition to the typical type I LTA present in other streptococci-a second, mixed-type series of LTA molecules of high complexity. We observed a ST-specific difference in the incorporation of glycosyl residues into these mixed-type LTAs. We found that strains P1/7 (ST1, high virulence) and SC84 (ST7, very high virulence) can attach a 1,2-linked α-d-Glcp residue as branching substituent to an α-d-Glcp that is 1,3-linked to glycerol phosphate moieties and that is not present in strain 89-1591 (ST25, intermediate virulence). In contrast, the latter strain could glycosylate its LTA at the glycerol O-2 position, which was not observed in the other two strains. Using LTA preparations from WT strains and from mutants with an inactivated prolipoprotein diacylglyceryl transferase, resulting in deficient lipoprotein acylation, we show that S. suis LTAs alone do not induce Toll-like receptor 2-dependent pro-inflammatory mediator production from dendritic cells. In summary, our study reveals an unexpected complexity of LTAs present in three S. suis serotype 2 strains differing in genetic background and virulence.


Asunto(s)
Adyuvantes Inmunológicos/química , Células Dendríticas/efectos de los fármacos , Lipopolisacáridos/química , Streptococcus suis/química , Ácidos Teicoicos/química , Transferasas/deficiencia , Adyuvantes Inmunológicos/aislamiento & purificación , Adyuvantes Inmunológicos/farmacología , Animales , Conformación de Carbohidratos , Secuencia de Carbohidratos , Quimiocina CCL3/genética , Quimiocina CCL3/inmunología , Quimiocina CXCL1/genética , Quimiocina CXCL1/inmunología , Células Dendríticas/citología , Células Dendríticas/inmunología , Expresión Génica , Glicosilación , Interleucina-6/genética , Interleucina-6/inmunología , Lipopolisacáridos/aislamiento & purificación , Lipopolisacáridos/farmacología , Ratones , Ratones Endogámicos C57BL , Éteres Fosfolípidos/química , Cultivo Primario de Células , Serogrupo , Streptococcus suis/clasificación , Streptococcus suis/patogenicidad , Relación Estructura-Actividad , Ácidos Teicoicos/aislamiento & purificación , Ácidos Teicoicos/farmacología , Receptor Toll-Like 2/genética , Receptor Toll-Like 2/inmunología , Transferasas/genética , Factor de Necrosis Tumoral alfa/genética , Factor de Necrosis Tumoral alfa/inmunología , Virulencia
16.
Vet Res ; 50(1): 62, 2019 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-31526397

RESUMEN

In the original publication of this article [1], the author name 'Pengchen Du' in author list should be 'Pengcheng Du'.

17.
Vet Res ; 50(1): 52, 2019 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-31262357

RESUMEN

Streptococcus suis serotype 2 is an important porcine pathogen and zoonotic agent causing sudden death, septic shock and meningitis, with exacerbated inflammation being a hallmark of the infection. A rapid, effective and balanced innate immune response against S. suis is critical to control bacterial growth without causing excessive inflammation. Even though interleukin (IL)-1 is one of the most potent and earliest pro-inflammatory mediators produced, its role in the S. suis pathogenesis has not been studied. We demonstrated that a classical virulent European sequence type (ST) 1 strain and the highly virulent ST7 strain induce important levels of IL-1 in systemic organs. Moreover, bone marrow-derived dendritic cells and macrophages contribute to its production, with the ST7 strain inducing higher levels. To better understand the underlying mechanisms involved, different cellular pathways were studied. Independently of the strain, IL-1ß production required MyD88 and involved recognition via TLR2 and possibly TLR7 and TLR9. This suggests that the recognized bacterial components are similar and conserved between strains. However, very high levels of the pore-forming toxin suilysin, produced only by the ST7 strain, are required for efficient maturation of pro-IL-1ß via activation of different inflammasomes resulting from pore formation and ion efflux. Using IL-1R-/- mice, we demonstrated that IL-1 signaling plays a beneficial role during S. suis systemic infection by modulating the inflammation required to control and clear bacterial burden, thus promoting host survival. Beyond a certain threshold, however, S. suis-induced inflammation cannot be counterbalanced by this signaling, making it difficult to discriminate its role.


Asunto(s)
Inmunidad Innata , Inflamación/veterinaria , Interleucina-1/metabolismo , Infecciones Estreptocócicas/veterinaria , Streptococcus suis/fisiología , Enfermedades de los Porcinos/microbiología , Animales , Modelos Animales de Enfermedad , Femenino , Inflamación/inmunología , Masculino , Ratones , Ratones Endogámicos C57BL , Serogrupo , Transducción de Señal , Infecciones Estreptocócicas/inmunología , Infecciones Estreptocócicas/microbiología , Porcinos , Enfermedades de los Porcinos/inmunología
18.
Remote Sens Environ ; 2352019 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-32440029

RESUMEN

This paper presents a Stage 3 validation of the recently released Collection 6 NASA MCD64A1 500 m global burned area product. The product is validated by comparison with Landsat 8 Operational Land Imager (OLI) image pairs acquired 16 days apart that were visually interpreted. These independent reference data were selected using a stratified random sampling approach that allows for probability sampling of Landsat data in both time and in space. A total of 558 Landsat 8 OLI image pairs (1116 images), acquired between March 1st, 2014 and March 19th , 2015, were selected and used to validate the MCD64A1 product. The areal accuracy of the MCD64A1 product was characterized at the 30 m resolution of the Landsat independent reference data using standard accuracy metrics derived from global and from biome specific confusion matrices. Because a probability based Stage 3 sampling protocol was followed, unbiased estimators of the accuracy metrics and associated standard errors could be used. Globally, the MCD64A1 product had an estimated 40.2% commission error and 72.6% omission error; the prevalence of omission errors is reflected by a negative estimated bias of the mapped global area burned relative to the Landsat independent reference data (-54.1%). Globally, the standard errors of the accuracy metrics were less than 6%. The lowest errors were observed in the boreal forest biome (27.0% omission and 23.9% estimated commission errors) where burned areas tend to be large and distinct, and remain on the landscape for long periods, and the highest errors were in the Tropical Forest, Temperate Forest, and Mediterranean biomes (estimated > 90% omission error and > 50% commission error). The product accuracy was also characterized at coarser scale using metrics derived from the regression between the proportion of coarse resolution grid cells detected as burned by MCD64A1 and the proportion mapped in the Landsat 8 interpreted maps. The errors of omission and commission observed at 30 m resolution compensate to a considerable extent at coarser resolution, as indicated by the coefficient of determination (r2 > 0.70), slope (> 0.79) and intercept (-0.0030) of the regression between the MCD64A1 product and the Landsat independent reference data in 3 km, 4 km, 5 km, and 6 km coarse resolution cells. The Boreal Forest, Desert and Xeric Shrublands, Temperate Savannah and Tropical Savannah biomes had higher r 2 and slopes closer to unity than the Temperate Forest, Mediterranean, and Tropical Forest biomes. The analysis of the deviations between the proportion of area burned mapped by the MCD64A1 product and by the independent reference data, performed using 3 km × 3 km and 6 km × 6 km coarse resolution cells, indicates that the large negative bias in global area burned is primarily due to the systematic underestimation of smaller burned areas in the MCD64A1 product.

19.
Acta Paediatr ; 108(4): 712-717, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30118160

RESUMEN

AIM: In order to improve weight-related discussion with patients and minimise their discomfort, the terminology used by medical staff should be carefully chosen. The aim of the study was to identify the most motivating weight-related terminology to use with children with obesity. METHODS: Focus groups were used to generate a list of 12 weight-related terms in Hebrew, sent by a questionnaire to parents of children and adolescents with obesity. Terms were graded according to how desirable, stigmatising, blaming or motivating they were perceived. We identified the most positive and negative weight-based terms and conducted linear regressions to predict child motivation to lose weight when positive terms are used. RESULTS: The least stigmatising and most motivating and desirable terms were 'unhealthy body weight' and 'unhealthy lifestyle'. Medical staff mostly used 'overweight', which was relatively inoffensive yet not very motivating. 'Fat/obese' ('Shamen') was the most stigmatising and blaming term and the least desired. Only 20% of parents endorsed a nonverbal graphical tool to describe body size. CONCLUSION: Our findings encourage using health-based terminology over weight-based terminology to promote treatment and lifestyle changes in children with obesity. Healthcare professionals should adopt patient-centred care and improve the weight-related terms they use with children with obesity.


Asunto(s)
Actitud Frente a la Salud , Peso Corporal , Padres/psicología , Obesidad Infantil , Terminología como Asunto , Adolescente , Adulto , Anciano , Niño , Comportamiento del Consumidor , Femenino , Humanos , Masculino , Persona de Mediana Edad , Motivación , Adulto Joven
20.
J Environ Manage ; 250: 109479, 2019 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-31499467

RESUMEN

Distributed environmental research infrastructures are important to support assessments of the effects of global change on landscapes, ecosystems and society. These infrastructures need to provide continuity to address long-term change, yet be flexible enough to respond to rapid societal and technological developments that modify research priorities. We used a horizon scanning exercise to identify and prioritize emerging research questions for the future development of ecosystem and socio-ecological research infrastructures in Europe. Twenty research questions covered topics related to (i) ecosystem structures and processes, (ii) the impacts of anthropogenic drivers on ecosystems, (iii) ecosystem services and socio-ecological systems and (iv), methods and research infrastructures. Several key priorities for the development of research infrastructures emerged. Addressing complex environmental issues requires the adoption of a whole-system approach, achieved through integration of biotic, abiotic and socio-economic measurements. Interoperability among different research infrastructures needs to be improved by developing standard measurements, harmonizing methods, and establishing capacities and tools for data integration, processing, storage and analysis. Future research infrastructures should support a range of methodological approaches including observation, experiments and modelling. They should also have flexibility to respond to new requirements, for example by adjusting the spatio-temporal design of measurements. When new methods are introduced, compatibility with important long-term data series must be ensured. Finally, indicators, tools, and transdisciplinary approaches to identify, quantify and value ecosystem services across spatial scales and domains need to be advanced.


Asunto(s)
Ecología , Ecosistema , Europa (Continente)
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