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1.
Nature ; 583(7816): 469-472, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32408336

RESUMO

A new coronavirus was recently discovered and named severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Infection with SARS-CoV-2 in humans causes coronavirus disease 2019 (COVID-19) and has been rapidly spreading around the globe1,2. SARS-CoV-2 shows some similarities to other coronaviruses; however, treatment options and an understanding of how SARS-CoV-2 infects cells are lacking. Here we identify the host cell pathways that are modulated by SARS-CoV-2 and show that inhibition of these pathways prevents viral replication in human cells. We established a human cell-culture model for infection with a clinical isolate of SARS-CoV-2. Using this cell-culture system, we determined the infection profile of SARS-CoV-2 by translatome3 and proteome proteomics at different times after infection. These analyses revealed that SARS-CoV-2 reshapes central cellular pathways such as translation, splicing, carbon metabolism, protein homeostasis (proteostasis) and nucleic acid metabolism. Small-molecule inhibitors that target these pathways prevented viral replication in cells. Our results reveal the cellular infection profile of SARS-CoV-2 and have enabled the identification of drugs that inhibit viral replication. We anticipate that our results will guide efforts to understand the molecular mechanisms that underlie the modulation of host cells after infection with SARS-CoV-2. Furthermore, our findings provide insights for the development of therapies for the treatment of COVID-19.


Assuntos
Betacoronavirus/efeitos dos fármacos , Betacoronavirus/metabolismo , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/metabolismo , Terapia de Alvo Molecular , Pneumonia Viral/tratamento farmacológico , Pneumonia Viral/metabolismo , Proteômica , Betacoronavirus/genética , Betacoronavirus/crescimento & desenvolvimento , COVID-19 , Células CACO-2 , Carbono/metabolismo , Infecções por Coronavirus/genética , Infecções por Coronavirus/virologia , Avaliação Pré-Clínica de Medicamentos , Interações Hospedeiro-Patógeno/efeitos dos fármacos , Interações Hospedeiro-Patógeno/genética , Humanos , Técnicas In Vitro , Cinética , Pandemias , Pneumonia Viral/genética , Pneumonia Viral/virologia , Biossíntese de Proteínas/efeitos dos fármacos , Proteoma/metabolismo , Proteostase , Splicing de RNA , SARS-CoV-2 , Fatores de Tempo , Replicação Viral/efeitos dos fármacos , Tratamento Farmacológico da COVID-19
2.
Mol Plant Microbe Interact ; 37(4): 396-406, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38148303

RESUMO

We used serial block-face scanning electron microscopy (SBF-SEM) to study the host-pathogen interface between Arabidopsis cotyledons and the hemibiotrophic fungus Colletotrichum higginsianum. By combining high-pressure freezing and freeze-substitution with SBF-SEM, followed by segmentation and reconstruction of the imaging volume using the freely accessible software IMOD, we created 3D models of the series of cytological events that occur during the Colletotrichum-Arabidopsis susceptible interaction. We found that the host cell membranes underwent massive expansion to accommodate the rapidly growing intracellular hypha. As the fungal infection proceeded from the biotrophic to the necrotrophic stage, the host cell membranes went through increasing levels of disintegration culminating in host cell death. Intriguingly, we documented autophagosomes in proximity to biotrophic hyphae using transmission electron microscopy (TEM) and a concurrent increase in autophagic flux between early to mid/late biotrophic phase of the infection process. Occasionally, we observed osmiophilic bodies in the vicinity of biotrophic hyphae using TEM only and near necrotrophic hyphae under both TEM and SBF-SEM. Overall, we established a method for obtaining serial SBF-SEM images, each with a lateral (x-y) pixel resolution of 10 nm and an axial (z) resolution of 40 nm, that can be reconstructed into interactive 3D models using the IMOD. Application of this method to the Colletotrichum-Arabidopsis pathosystem allowed us to more fully understand the spatial arrangement and morphological architecture of the fungal hyphae after they penetrate epidermal cells of Arabidopsis cotyledons and the cytological changes the host cell undergoes as the infection progresses toward necrotrophy. [Formula: see text] Copyright © 2024 The Author(s). This is an open access article distributed under the CC BY 4.0 International license.


Assuntos
Arabidopsis , Colletotrichum , Cotilédone , Microscopia Eletrônica de Varredura , Doenças das Plantas , Colletotrichum/fisiologia , Colletotrichum/ultraestrutura , Colletotrichum/patogenicidade , Arabidopsis/microbiologia , Arabidopsis/ultraestrutura , Cotilédone/microbiologia , Cotilédone/ultraestrutura , Doenças das Plantas/microbiologia , Interações Hospedeiro-Patógeno , Hifas/ultraestrutura , Imageamento Tridimensional , Microscopia Eletrônica de Transmissão
3.
Appl Environ Microbiol ; 89(3): e0154322, 2023 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-36847530

RESUMO

Increases in Arctic temperatures have thawed permafrost and accelerated tundra soil microbial activity, releasing greenhouse gases that amplify climate warming. Warming over time has also accelerated shrub encroachment in the tundra, altering plant input abundance and quality, and causing further changes to soil microbial processes. To better understand the effects of increased temperature and the accumulated effects of climate change on soil bacterial activity, we quantified the growth responses of individual bacterial taxa to short-term warming (3 months) and long-term warming (29 years) in moist acidic tussock tundra. Intact soil was assayed in the field for 30 days using 18O-labeled water, from which taxon-specific rates of 18O incorporation into DNA were estimated as a proxy for growth. Experimental treatments warmed the soil by approximately 1.5°C. Short-term warming increased average relative growth rates across the assemblage by 36%, and this increase was attributable to emergent growing taxa not detected in other treatments that doubled the diversity of growing bacteria. However, long-term warming increased average relative growth rates by 151%, and this was largely attributable to taxa that co-occurred in the ambient temperature controls. There was also coherence in relative growth rates within broad taxonomic levels with orders tending to have similar growth rates in all treatments. Growth responses tended to be neutral in short-term warming and positive in long-term warming for most taxa and phylogenetic groups co-occurring across treatments regardless of phylogeny. Taken together, growing bacteria responded distinctly to short-term and long-term warming, and taxa growing in each treatment exhibited deep phylogenetic organization. IMPORTANCE Soil carbon stocks in the tundra and underlying permafrost have become increasingly vulnerable to microbial decomposition due to climate change. The microbial responses to Arctic warming must be understood in order to predict the effects of future microbial activity on carbon balance in a warming Arctic. In response to our warming treatments, tundra soil bacteria grew faster, consistent with increased rates of decomposition and carbon flux to the atmosphere. Our findings suggest that bacterial growth rates may continue to increase in the coming decades as faster growth is driven by the accumulated effects of long-term warming. Observed phylogenetic organization of bacterial growth rates may also permit taxonomy-based predictions of bacterial responses to climate change and inclusion into ecosystem models.


Assuntos
Ecossistema , Solo , Filogenia , Tundra , Regiões Árticas , Mudança Climática , Carbono/metabolismo
4.
Infection ; 51(3): 679-687, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36181634

RESUMO

INTRODUCTION: Tuberculosis (TB) is caused by M. tuberculosis complex (MTB) and pulmonary tuberculosis (PTB) is its classical manifestation. However, in some regions of the world, extrapulmonary TB (EPTB) seems to be more frequent. METHODS: We performed a retrospective cohort study of all TB patients treated at University Hospital Frankfurt, Germany, for the time period 2013-2018. Patient charts were reviewed and demographic, clinical, and microbiological data recorded. Patients were subdivided according to their geographic origins. RESULTS: Of the 378 included patients, 309 were born outside Germany (81.7%). Three WHO regions were significantly associated with the occurrence of isolated EPTB: the South-East Asian Region (OR 3.37, CI 1.74-6.66, p < 0.001), the African Region (2.20, CI 1.25-3.90, p = 0.006), and the Eastern Mediterranean Region (OR 3.18, CI 1.78-5.76, p < 0.001). On a country level, seven countries of origin could be demonstrated to be significantly associated with the occurrence of isolated EPTB: India (OR 5.58, CI 2.30-14.20, p < 0.001), Nepal (OR 12.75, CI 1.73-259.28, p = 0.027), Afghanistan (OR 3.64, CI 1.14-11.98, p = 0.029), Pakistan (OR 3.64, CI 1.14-11.98, p = 0.029), Eritrea (OR 3.32, CI 1.52-7.47, p = 0.003), Somalia (OR 7.08, CI 2.77-19.43, p < 0.001), and Turkey (OR 9.56, CI 2.52-47.19, p = 0.002). CONCLUSION: Geographical origin is a predictor for the occurrence of extrapulmonary TB. This might be linked to a delay in diagnosis in these patients, as well as specific responsible impairments of the host's immune system, possible virulence factors of MTB, and relevant comorbidities.


Assuntos
Mycobacterium , Tuberculose Extrapulmonar , Tuberculose Pulmonar , Tuberculose , Humanos , Estudos Retrospectivos , Tuberculose/diagnóstico , Tuberculose Pulmonar/tratamento farmacológico
5.
Oecologia ; 201(3): 771-782, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36847885

RESUMO

Density dependence in an ecological community has been observed in many macro-organismal ecosystems and is hypothesized to maintain biodiversity but is poorly understood in microbial ecosystems. Here, we analyze data from an experiment using quantitative stable isotope probing (qSIP) to estimate per-capita growth and mortality rates of bacterial populations in soils from several ecosystems along an elevation gradient which were subject to nutrient addition of either carbon alone (glucose; C) or carbon with nitrogen (glucose + ammonium-sulfate; C + N). Across all ecosystems, we found that higher population densities, quantified by the abundance of genomes per gram of soil, had lower per-capita growth rates in C + N-amended soils. Similarly, bacterial mortality rates in C + N-amended soils increased at a significantly higher rate with increasing population size than mortality rates in control and C-amended soils. In contrast to the hypothesis that density dependence would promote or maintain diversity, we observed significantly lower bacterial diversity in soils with stronger negative density-dependent growth. Here, density dependence was significantly but weakly responsive to nutrients and was not associated with higher bacterial diversity.


Assuntos
Ecossistema , Solo , Microbiologia do Solo , Bactérias , Carbono
6.
Int J Mol Sci ; 24(3)2023 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-36768138

RESUMO

Inflammation is intimately involved in the pathogenesis of diabetic kidney disease. Inhibition of SGLT-2 by a specific class of drugs, gliflozins, has been shown to reduce inflammation and attenuate the progression of diabetic nephropathy, in addition to its main effect of inhibiting renal glucose reabsorption. We used highly purified human renal proximal tubular epithelial cells (PTCs) as an in vitro model to study the cellular response to a diabetic (high glucose) and inflammatory (cytokines) microenvironment and the effect of gliflozins. In this context, we investigated the influence of SGLT-2 inhibition by empa- and dapagliflozin (500 nM) on the expression of pro-inflammatory factors (IL-1ß, IL-6, TNF-α, MCP-1, and ICAM-1). The results clearly indicate an anti-inflammatory effect of both gliflozins. Although induced expression of the four cytokines was only slightly attenuated, there was a clear effect on the expression of the adhesion molecule ICAM-1, a master regulator of cellular responses in inflammation and injury resolution. The induced expression of ICAM-1 mRNA was significantly reduced by approximately 13.5% by empagliflozin and also showed an inhibitory trend with dapagliflozin. However, induced ICAM-1 protein expression was significantly inhibited from 24.71 ± 1.0 ng/mL to 18.81 ± 3.9 (empagliflozin) and 19.62 ± 2.1 ng/mL (dapagliflozin). In conclusion, an additional anti-inflammatory effect of empa- and dapagliflozin in therapeutically observed concentrations was demonstrated in primary human PTCs in vitro.


Assuntos
Diabetes Mellitus , Nefropatias Diabéticas , Inibidores do Transportador 2 de Sódio-Glicose , Humanos , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêutico , Molécula 1 de Adesão Intercelular/genética , Molécula 1 de Adesão Intercelular/metabolismo , Nefropatias Diabéticas/metabolismo , Glucose/metabolismo , Células Epiteliais/metabolismo , Inflamação/metabolismo , Citocinas/metabolismo , Anti-Inflamatórios/uso terapêutico , Diabetes Mellitus/metabolismo
7.
Glob Chang Biol ; 28(1): 128-139, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34587352

RESUMO

The carbon stored in soil exceeds that of plant biomass and atmospheric carbon and its stability can impact global climate. Growth of decomposer microorganisms mediates both the accrual and loss of soil carbon. Growth is sensitive to temperature and given the vast biological diversity of soil microorganisms, the response of decomposer growth rates to warming may be strongly idiosyncratic, varying among taxa, making ecosystem predictions difficult. Here, we show that 15 years of warming by transplanting plant-soil mesocosms down in elevation, strongly reduced the growth rates of soil microorganisms, measured in the field using undisturbed soil. The magnitude of the response to warming varied among microbial taxa. However, the direction of the response-reduced growth-was universal and warming explained twofold more variation than did the sum of taxonomic identity and its interaction with warming. For this ecosystem, most of the growth responses to warming could be explained without taxon-specific information, suggesting that in some cases microbial responses measured in aggregate may be adequate for climate modeling. Long-term experimental warming also reduced soil carbon content, likely a consequence of a warming-induced increase in decomposition, as warming-induced changes in plant productivity were negligible. The loss of soil carbon and decreased microbial biomass with warming may explain the reduced growth of the microbial community, more than the direct effects of temperature on growth. These findings show that direct and indirect effects of long-term warming can reduce growth rates of soil microbes, which may have important feedbacks to global warming.


Assuntos
Microbiota , Solo , Carbono , Mudança Climática , Ecossistema , Pradaria , Microbiologia do Solo
8.
Crit Care ; 26(1): 181, 2022 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-35715801

RESUMO

BACKGROUND: Bacterial burden as well as duration of bacteremia influence the outcome of patients with bloodstream infections. Promptly decreasing bacterial load in the blood by using extracorporeal devices in addition to anti-infective therapy has recently been explored. Preclinical studies with the Seraph® 100 Microbind® Affinity Blood Filter (Seraph® 100), which consists of heparin that is covalently bound to polymer beads, have demonstrated an effective binding of bacteria and viruses. Pathogens adhere to the heparin coated polymer beads in the adsorber as they would normally do to heparan sulfate on cell surfaces. Using this biomimetic principle, the Seraph® 100 could help to decrease bacterial burden in vivo. METHODS: This first in human, prospective, multicenter, non-randomized interventional study included patients with blood culture positive bloodstream infection and the need for kidney replacement therapy as an adjunctive treatment for bloodstream infections. We performed a single four-hour hemoperfusion treatment with the Seraph® 100 in conjunction with a dialysis procedure. Post procedure follow up was 14 days. RESULTS: Fifteen hemodialysis patients (3F/12 M, age 74.0 [68.0-78.5] years, dialysis vintage 28.0 [11.0-45.0] months) were enrolled. Seraph® 100 treatment started 66.4 [45.7-80.6] hours after the initial positive blood culture was drawn. During the treatment with the Seraph® 100 with a median blood flow of 285 [225-300] ml/min no device or treatment related adverse events were reported. Blood pressure and heart rate remained stable while peripheral oxygen saturation improved during the treatment from 98.0 [92.5-98.0] to 99.0 [98.0-99.5] %; p = 0.0184. Four patients still had positive blood culture at the start of Seraph® 100 treatment. In one patient blood cultures turned negative during treatment. The time to positivity (TTP) was increased between inflow and outflow blood cultures by 36 [- 7.2 to 96.3] minutes. However, overall TTP increase was not statistical significant. CONCLUSIONS: Seraph® 100 treatment was well tolerated. Adding Seraph® 100 to antibiotics early in the course of bacteremia might result in a faster resolution of bloodstream infections, which has to be evaluated in further studies. TRAIL REGISTRATION: ClinicalTrials.gov Identifier: NCT02914132 , first posted September 26, 2016.


Assuntos
Bacteriemia , Diálise Renal , Idoso , Bacteriemia/tratamento farmacológico , Bactérias , Heparina/farmacologia , Heparina/uso terapêutico , Humanos , Polímeros , Estudos Prospectivos
9.
Int J Mol Sci ; 23(13)2022 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-35806391

RESUMO

Mesenchymal stromal/stem cells and their derivates are the most promising cell source for cell therapies in regenerative medicine. The application of extracellular vesicles (EVs) as cell-free therapeuticals requires particles with a maximum regenerative capability to enhance tissue and organ regeneration. The cargo of mRNA and microRNA (miR) in EVs after hypoxic preconditioning has not been extensively investigated. Therefore, the aim of our study was the characterization of mRNA and the miR loading of EVs. We further investigated the effects of the isolated EVs on renal tubular epithelial cells in vitro. We found 3131 transcripts to be significantly regulated upon hypoxia. Only 15 of these were downregulated, but 3116 were up-regulated. In addition, we found 190 small RNAs, 169 of these were miRs and 21 were piwi-interacting RNAs (piR). However, only 18 of the small RNAs were significantly altered, seven were miRs and 11 were piRs. Interestingly, all seven miRs were down-regulated after hypoxic pretreatment, whereas all 11 piRs were up-regulated. Gene ontology term enrichment and miR-target enrichment analysis of the mRNAs and miR were also performed in order to study the biological background. Finally, the therapeutic effect of EVs on human renal tubular epithelial cells was shown by the increased expression of three anti-inflammatory molecules after incubation with EVs from hypoxic pretreatment. In summary, our study demonstrates the altered mRNA and miR load in EVs after hypoxic preconditioning, and their anti-inflammatory effect on epithelial cells.


Assuntos
Vesículas Extracelulares , Células-Tronco Mesenquimais , MicroRNAs , Vesículas Extracelulares/metabolismo , Humanos , Hipóxia/metabolismo , Células-Tronco Mesenquimais/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Mensageiro/genética
11.
Int J Mol Sci ; 22(6)2021 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-33808970

RESUMO

Cell-free therapy using extracellular vesicles (EVs) from adipose-derived mesenchymal stromal/stem cells (ASCs) seems to be a safe and effective therapeutic option to support tissue and organ regeneration. The application of EVs requires particles with a maximum regenerative capability and hypoxic culture conditions as an in vitro preconditioning regimen has been shown to alter the molecular composition of released EVs. Nevertheless, the EV cargo after hypoxic preconditioning has not yet been comprehensively examined. The aim of the present study was the characterization of EVs from hypoxic preconditioned ASCs. We investigated the EV proteome and their effects on renal tubular epithelial cells in vitro. While no effect of hypoxia was observed on the number of released EVs and their protein content, the cargo of the proteins was altered. Proteomic analysis showed 41 increased or decreased proteins, 11 in a statistically significant manner. Furthermore, the uptake of EVs in epithelial cells and a positive effect on oxidative stress in vitro were observed. In conclusion, culture of ASCs under hypoxic conditions was demonstrated to be a promising in vitro preconditioning regimen, which alters the protein cargo and increases the anti-oxidative potential of EVs. These properties may provide new potential therapeutic options for regenerative medicine.


Assuntos
Vesículas Extracelulares/genética , Proteoma/genética , Proteômica , Medicina Regenerativa/métodos , Terapia Baseada em Transplante de Células e Tecidos/tendências , Células Cultivadas , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Humanos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , MicroRNAs/genética , Regeneração/genética
12.
Int J Mol Sci ; 21(3)2020 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-32050569

RESUMO

Damage to kidney cells can occur due to a variety of ischemic and toxic insults and leads to inflammation and cell death, which can result in acute kidney injury (AKI) [...].


Assuntos
Nefropatias/fisiopatologia , Rim/fisiologia , Animais , Humanos , Rim/metabolismo , Rim/fisiopatologia , Nefropatias/metabolismo , Regeneração
13.
Int J Mol Sci ; 21(2)2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31936266

RESUMO

Gliflozins are inhibitors of the renal proximal tubular sodium-glucose co-transporter-2 (SGLT-2), that inhibit reabsorption of urinary glucose and they are able to reduce hyperglycemia in patients with type 2 diabetes. A renoprotective function of gliflozins has been proven in diabetic nephropathy, but harmful side effects on the kidney have also been described. In the current project, primary highly purified human renal proximal tubular epithelial cells (PTCs) have been shown to express functional SGLT-2, and were used as an in vitro model to study possible cellular damage induced by two therapeutically used gliflozins: empagliflozin and dapagliflozin. Cell viability, proliferation, and cytotoxicity assays revealed that neither empagliflozin nor dapagliflozin induce effects in PTCs cultured in a hyperglycemic environment, or in co-medication with ramipril or hydro-chloro-thiazide. Oxidative stress was significantly lowered by dapagliflozin but not by empagliflozin. No effect of either inhibitor could be detected on mRNA and protein expression of the pro-inflammatory cytokine interleukin-6 and the renal injury markers KIM-1 and NGAL. In conclusion, empa- and dapagliflozin in therapeutic concentrations were shown to induce no direct cell injury in cultured primary renal PTCs in hyperglycemic conditions.


Assuntos
Compostos Benzidrílicos/farmacologia , Diabetes Mellitus Tipo 2/tratamento farmacológico , Nefropatias Diabéticas/tratamento farmacológico , Glucosídeos/farmacologia , Transportador 2 de Glucose-Sódio/genética , Compostos Benzidrílicos/efeitos adversos , Glicemia/efeitos dos fármacos , Linhagem Celular , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/patologia , Nefropatias Diabéticas/etiologia , Nefropatias Diabéticas/genética , Nefropatias Diabéticas/patologia , Células Epiteliais/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Glucosídeos/efeitos adversos , Humanos , Hipoglicemiantes/farmacologia , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Inflamação/patologia , Rim/efeitos dos fármacos , Rim/patologia , Túbulos Renais Proximais/efeitos dos fármacos , Túbulos Renais Proximais/patologia , Estresse Oxidativo/efeitos dos fármacos , Inibidores do Transportador 2 de Sódio-Glicose/farmacologia
14.
Psychol Res ; 83(6): 1269-1280, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29270673

RESUMO

In everyday life, both the head and the hand movements of another person reveal the other's action target. However, studies on the development of action prediction have primarily included displays in which only hand and no head movements were visible. Given that infants acquire in their first year both the ability to follow other's gaze and the ability to predict other's reaching actions, the question is whether they rely mostly on the hand or the head when predicting other's manual actions. The current study aimed to provide an answer to this question using a screen-based eye tracking setup. Thirteen-month-old infants observed a model transporting plastic rings from one side of the screen to the other side and place them on a pole. In randomized trials the model's head was either visible or occluded. The dependent variable was gaze-arrival time, which indicated whether participants predicted the model's action targets. Gaze-arrival times were not found to be different when the head was visible or rendered invisible. Furthermore, target looks that occurred after looks at the hand were found to be predictive, whereas target looks that occurred after looks at the head were reactive. In sum, the study shows that 13-month-olds are capable of predicting an individual's action target based on the observed hand movements but not the head movements. The data suggest that earlier findings on infants' action prediction in screen-based tasks in which often only the hands were visible may well generalize to real-life settings in which infants have visual access to the actor's head.


Assuntos
Atenção/fisiologia , Mãos/fisiologia , Movimentos da Cabeça/fisiologia , Movimento/fisiologia , Desempenho Psicomotor/fisiologia , Feminino , Humanos , Lactente , Masculino
15.
Environ Microbiol ; 20(3): 1112-1119, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29411496

RESUMO

Nitrogen (N) is frequently a limiting nutrient in soil; its availability can govern ecosystem functions such as primary production and decomposition. Assimilation of N by microorganisms impacts the availability of N in soil. Despite its established ecological significance, the contributions of microbial taxa to N assimilation are unknown. Here we measure N uptake and use by microbial phylotypes and taxonomic groups within a diverse assemblage of soil microbes through quantitative stable isotope probing (qSIP) with 15 N. Following incubation with 15 NH4+, distinct patterns of 15 N assimilation among taxonomic groups were observed. For instance, glucose addition stimulated 15 N assimilation in most members of Actinobacteria and Proteobacteria but generally decreased 15 N use by Firmicutes and Bacteriodetes. While NH4+ is considered a preferred and universal source of N to prokaryotes, the majority (> 80%) of N assimilation in our soils could be attributed to a handful of active orders. Characterizing N assimilation of taxonomic groups with 15 N qSIP may provide a basis for understanding how microbial community composition influences N availability in the environment.


Assuntos
Actinobacteria/metabolismo , Compostos de Amônio/metabolismo , Bacteroidetes/metabolismo , Firmicutes/metabolismo , Isótopos de Nitrogênio/metabolismo , Nitrogênio/análise , Proteobactérias/metabolismo , Actinobacteria/classificação , Bacteroidetes/classificação , Ecologia , Firmicutes/classificação , Microbiota , Proteobactérias/classificação , Solo , Microbiologia do Solo
16.
BMC Microbiol ; 18(1): 174, 2018 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-30390618

RESUMO

BACKGROUND: We sought to determine if the prevalence of antibiotic-resistant Escherichia coli differed across retail poultry products and among major production categories, including organic, "raised without antibiotics", and conventional. RESULTS: We collected all available brands of retail chicken and turkey-including conventional, "raised without antibiotic", and organic products-every two weeks from January to December 2012. In total, E. coli was recovered from 91% of 546 turkey products tested and 88% of 1367 chicken products tested. The proportion of samples contaminated with E. coli was similar across all three production categories. Resistance prevalence varied by meat type and was highest among E. coli isolates from turkey for the majority of antibiotics tested. In general, production category had little effect on resistance prevalence among E. coli isolates from chicken, although resistance to gentamicin and multidrug resistance did vary. In contrast, resistance prevalence was significantly higher for 6 of the antibiotics tested-and multidrug resistance-among isolates from conventional turkey products when compared to those labelled organic or "raised without antibiotics". E. coli isolates from chicken varied strongly in resistance prevalence among different brands within each production category. CONCLUSION: The high prevalence of resistance among E. coli isolates from conventionally-raised turkey meat suggests greater antimicrobial use in conventional turkey production as compared to "raised without antibiotics" and organic systems. However, among E. coli from chicken meat, resistance prevalence was more strongly linked to brand than to production category, which could be caused by brand-level differences during production and/or processing, including variations in antimicrobial use.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla , Escherichia coli/efeitos dos fármacos , Microbiologia de Alimentos , Alimentos Orgânicos/microbiologia , Aves Domésticas/microbiologia , Animais , Galinhas/microbiologia , Farmacorresistência Bacteriana Múltipla/genética , Escherichia coli/genética , Contaminação de Alimentos , Genes Bacterianos/genética , Testes de Sensibilidade Microbiana , Perus/microbiologia
17.
Blood Purif ; 46(2): 126-133, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29698959

RESUMO

BACKGROUND/AIMS: Middle East respiratory syndrome coronavirus (MERS-CoV) and Marburg virus (MARV) are among the World Health Organization's top 8 emerging pathogens. Both zoonoses share nonspecific early symptoms, a high lethality rate, and a reduced number of specific treatment options. Therefore, we evaluated extracorporeal virus and glycoprotein (GP) elimination by lectin affinity plasmapheresis (LAP). METHODS: For both MERS-CoV (pseudovirus) as well as MARV (GPs), 4 LAP devices (Mini Hemopurifiers, Aethlon Medical, San Diego, CA, USA) and 4 negative controls were tested. Samples were collected every 30 min and analyzed for reduction in virus infectivity by a flow cytometry-based infectivity assay (MERS-CoV) and in soluble GP content (MARV) by an immunoassay. RESULTS: The experiments show a time-dependent clearance of MERS-CoV of up to 80% within 3 h (pseudovirus). Up to 70% of MARV-soluble GPs were eliminated at the same time. Substantial saturation of the binding resins was detected within the first treatment hour. CONCLUSION: MERS-CoV (pseudovirus) and MARV soluble GPs are eliminated by LAP in vitro. Considering the high lethality and missing established treatment options, LAP should be evaluated in vivo. Especially early initiation, continuous therapy, and timed cartridge exchanges could be of importance.


Assuntos
Glicoproteínas/isolamento & purificação , Marburgvirus/isolamento & purificação , Coronavírus da Síndrome Respiratória do Oriente Médio/isolamento & purificação , Plasmaferese/métodos , Animais , Estudos de Casos e Controles , Citometria de Fluxo , Humanos , Imunoensaio , Lectinas/metabolismo , Marburgvirus/química , Plasmaferese/instrumentação , Plasmaferese/normas , Zoonoses
18.
Int J Mol Sci ; 19(6)2018 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-29890767

RESUMO

Stem cell-based therapies require cells with a maximum regenerative capacity in order to support regeneration after tissue injury and organ failure. Optimization of this regenerative potential of mesenchymal stromal/stem cells (MSC) or their conditioned medium by in vitro preconditioning regimens are considered to be a promising strategy to improve the release of regenerative factors. In the present study, MSC were isolated from inguinal adipose tissue (mASC) from C57BL/6 mice, cultured, and characterized. Then, mASC were either preconditioned by incubation in a hypoxic environment (0.5% O2), or in normoxia in the presence of murine epidermal growth factor (EGF) or tumor necrosis factor α (TNFα) for 48 h. Protein expression was measured by a commercially available array. Selected factors were verified by PCR analysis. The expression of 83 out of 308 proteins (26.9%) assayed was found to be increased after preconditioning with TNFα, whereas the expression of 61 (19.8%) and 70 (22.7%) proteins was increased after incubation with EGF or in hypoxia, respectively. Furthermore, we showed the proliferation-promoting effects of the preconditioned culture supernatants on injured epithelial cells in vitro. Our findings indicate that each preconditioning regimen tested induced an individual expression profile with a wide variety of factors, including several growth factors and cytokines, and therefore may enhance the regenerative potential of mASC for cell-based therapies.


Assuntos
Tecido Adiposo/citologia , Técnicas de Cultura de Células/métodos , Perfilação da Expressão Gênica , Células-Tronco Mesenquimais/citologia , Animais , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Meios de Cultivo Condicionados/farmacologia , Células Epiteliais/citologia , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Camundongos Endogâmicos C57BL , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
19.
Ecology ; 98(5): 1475, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28263380

RESUMO

Animals can be important in modulating ecosystem-level nutrient cycling, although their importance varies greatly among species and ecosystems. Nutrient cycling rates of individual animals represent valuable data for testing the predictions of important frameworks such as the Metabolic Theory of Ecology (MTE) and ecological stoichiometry (ES). They also represent an important set of functional traits that may reflect both environmental and phylogenetic influences. Over the past two decades, studies of animal-mediated nutrient cycling have increased dramatically, especially in aquatic ecosystems. Here we present a global compilation of aquatic animal nutrient excretion rates. The dataset includes 10,534 observations from freshwater and marine animals of N and/or P excretion rates. These observations represent 491 species, including most aquatic phyla. Coverage varies greatly among phyla and other taxonomic levels. The dataset includes information on animal body size, ambient temperature, taxonomic affiliations, and animal body N:P. This data set was used to test predictions of MTE and ES, as described in Vanni and McIntyre (2016; Ecology DOI: 10.1002/ecy.1582).


Assuntos
Organismos Aquáticos/metabolismo , Nitrogênio/metabolismo , Fósforo/metabolismo , Animais , Ecossistema , Água Doce , Filogenia
20.
Gesundheitswesen ; 79(S 01): S11-S19, 2017 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-28399581

RESUMO

The benefits of physical activity and a reduction of sedentary behaviour in childhood and adolescence are well established.Based on a quality-assured literature review, the German recommendations were updated. Guidelines for infants, toddlers, children of kindergarten and primary school age and youth are clearly depictedIn general, a higher amount of physical activity is associated with more health benefits. Preschool age children should have 180 min of physical activity daily, and from primary school age on, at least 90 min daily are recommended. Sedentary behaviour, especially time in front of screens, is to be reduced to a minimum.


Assuntos
Saúde do Adolescente/normas , Saúde da Criança/normas , Bases de Dados Factuais/normas , Exercício Físico , Promoção da Saúde/normas , Guias de Prática Clínica como Assunto , Comportamento Sedentário , Adolescente , Criança , Pré-Escolar , Terapia por Exercício/normas , Feminino , Alemanha , Humanos , Lactente , Recém-Nascido , Masculino , Condicionamento Físico Humano/normas , Sistema de Registros , Reabilitação/normas , Comportamento de Redução do Risco
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