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1.
Nat Immunol ; 19(8): 838-848, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29988091

RESUMEN

Foxo transcription factors play an essential role in regulating specialized lymphocyte functions and in maintaining T cell quiescence. Here, we used a system in which Foxo1 transcription-factor activity, which is normally terminated upon cell activation, cannot be silenced, and we show that enforcing Foxo1 activity disrupts homeostasis of CD4 conventional and regulatory T cells. Despite limiting cell metabolism, continued Foxo1 activity is associated with increased activation of the kinase Akt and a cell-intrinsic proliferative advantage; however, survival and cell division are decreased in a competitive setting or growth-factor-limiting conditions. Via control of expression of the transcription factor Myc and the IL-2 receptor ß-chain, termination of Foxo1 signaling couples the increase in cellular cholesterol to biomass accumulation after activation, thereby facilitating immunological synapse formation and mTORC1 activity. These data reveal that Foxo1 regulates the integration of metabolic and mitogenic signals essential for T cell competitive fitness and the coordination of cell growth with cell division.


Asunto(s)
Linfocitos T CD4-Positivos/fisiología , Proteína Forkhead Box O1/metabolismo , Linfocitos T Reguladores/fisiología , Animales , Proliferación Celular , Células Cultivadas , Colesterol/metabolismo , Proteína Forkhead Box O1/genética , Perfilación de la Expresión Génica , Homeostasis , Sinapsis Inmunológicas/metabolismo , Subunidad beta del Receptor de Interleucina-2/genética , Subunidad beta del Receptor de Interleucina-2/metabolismo , Activación de Linfocitos , Diana Mecanicista del Complejo 1 de la Rapamicina/metabolismo , Ratones , Ratones Noqueados , Proteínas Proto-Oncogénicas c-akt/metabolismo , Proteínas Proto-Oncogénicas c-myc/genética , Proteínas Proto-Oncogénicas c-myc/metabolismo , Transducción de Señal
2.
Cell ; 157(3): 595-610, 2014 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-24766807

RESUMEN

PTEN dysfunction plays a crucial role in the pathogenesis of hereditary and sporadic cancers. Here, we show that PTEN homodimerizes and, in this active conformation, exerts lipid phosphatase activity on PtdIns(3,4,5)P3. We demonstrate that catalytically inactive cancer-associated PTEN mutants heterodimerize with wild-type PTEN and constrain its phosphatase activity in a dominant-negative manner. To study the consequences of homo- and heterodimerization of wild-type and mutant PTEN in vivo, we generated Pten knockin mice harboring two cancer-associated PTEN mutations (PtenC124S and PtenG129E). Heterozygous Pten(C124S/+) and Pten(G129E/+) cells and tissues exhibit increased sensitivity to PI3-K/Akt activation compared to wild-type and Pten(+/-) counterparts, whereas this difference is no longer apparent between Pten(C124S/-) and Pten(-/-) cells. Notably, Pten KI mice are more tumor prone and display features reminiscent of complete Pten loss. Our findings reveal that PTEN loss and PTEN mutations are not synonymous and define a working model for the function and regulation of PTEN.


Asunto(s)
Fosfohidrolasa PTEN/genética , Fosfohidrolasa PTEN/metabolismo , Transducción de Señal , Animales , Embrión de Mamíferos/citología , Femenino , Humanos , Pérdida de Heterocigocidad , Masculino , Ratones , Mutación , Multimerización de Proteína , Proteínas Proto-Oncogénicas c-akt/metabolismo
3.
Nat Immunol ; 17(6): 618-25, 2016 05 19.
Artículo en Inglés | MEDLINE | ID: mdl-27196520

RESUMEN

The bidirectional interaction between the immune system and whole-body metabolism has been well recognized for many years. Via effects on adipocytes and hepatocytes, immune cells can modulate whole-body metabolism (in metabolic syndromes such as type 2 diabetes and obesity) and, reciprocally, host nutrition and commensal-microbiota-derived metabolites modulate immunological homeostasis. Studies demonstrating the metabolic similarities of proliferating immune cells and cancer cells have helped give birth to the new field of immunometabolism, which focuses on how the cell-intrinsic metabolic properties of lymphocytes and macrophages can themselves dictate the fate and function of the cells and eventually shape an immune response. We focus on this aspect here, particularly as it relates to regulatory T cells.


Asunto(s)
Adipocitos/inmunología , Diabetes Mellitus Tipo 2/inmunología , Macrófagos/metabolismo , Síndrome Metabólico/inmunología , Obesidad/inmunología , Linfocitos T Reguladores/metabolismo , Animales , Homeostasis , Humanos , Inmunidad , Microbiota , Tolerancia Periférica
4.
N Engl J Med ; 389(3): 215-227, 2023 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-37467497

RESUMEN

BACKGROUND: Natural history studies have correlated serotype-specific anti-capsular polysaccharide (CPS) IgG in newborns with a reduced risk of group B streptococcal disease. A hexavalent CPS-cross-reactive material 197 glycoconjugate vaccine (GBS6) is being developed as a maternal vaccine to prevent invasive group B streptococcus in young infants. METHODS: In an ongoing phase 2, placebo-controlled trial involving pregnant women, we assessed the safety and immunogenicity of a single dose of various GBS6 formulations and analyzed maternally transferred anti-CPS antibodies. In a parallel seroepidemiologic study that was conducted in the same population, we assessed serotype-specific anti-CPS IgG concentrations that were associated with a reduced risk of invasive disease among newborns through 89 days of age to define putative protective thresholds. RESULTS: Naturally acquired anti-CPS IgG concentrations were associated with a reduced risk of disease among infants in the seroepidemiologic study. IgG thresholds that were determined to be associated with 75 to 95% reductions in the risk of disease were 0.184 to 0.827 µg per milliliter. No GBS6-associated safety signals were observed among the mothers or infants. The incidence of adverse events and of serious adverse events were similar across the trial groups for both mothers and infants; more local reactions were observed in the groups that received GBS6 containing aluminum phosphate. Among the infants, the most common serious adverse events were minor congenital anomalies (umbilical hernia and congenital dermal melanocytosis). GBS6 induced maternal antibody responses to all serotypes, with maternal-to-infant antibody ratios of approximately 0.4 to 1.3, depending on the dose. The percentage of infants with anti-CPS IgG concentrations above 0.184 µg per milliliter varied according to serotype and formulation, with 57 to 97% of the infants having a seroresponse to the most immunogenic formulation. CONCLUSIONS: GBS6 elicited anti-CPS antibodies against group B streptococcus in pregnant women that were transferred to infants at levels associated with a reduced risk of invasive group B streptococcal disease. (Funded by Pfizer and the Bill and Melinda Gates Foundation; C1091002 ClinicalTrials.gov number, NCT03765073.).


Asunto(s)
Infecciones Estreptocócicas , Vacunas Estreptocócicas , Streptococcus agalactiae , Femenino , Humanos , Lactante , Recién Nacido , Embarazo , Anticuerpos Antibacterianos , Inmunoglobulina G , Estudios Seroepidemiológicos , Infecciones Estreptocócicas/epidemiología , Infecciones Estreptocócicas/inmunología , Infecciones Estreptocócicas/prevención & control , Vacunas Combinadas/administración & dosificación , Vacunas Combinadas/efectos adversos , Vacunas Combinadas/inmunología , Vacunas Combinadas/uso terapéutico , Vacunas Conjugadas/administración & dosificación , Vacunas Conjugadas/efectos adversos , Vacunas Conjugadas/inmunología , Vacunas Conjugadas/uso terapéutico , Vacunas Estreptocócicas/administración & dosificación , Vacunas Estreptocócicas/efectos adversos , Vacunas Estreptocócicas/inmunología , Vacunas Estreptocócicas/uso terapéutico , Inmunidad Materno-Adquirida/inmunología
5.
Environ Microbiol ; 22(1): 433-446, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31736217

RESUMEN

The Laurentian Great Lakes are a vast, interconnected freshwater system spanning strong physicochemical gradients, thus constituting a powerful natural laboratory for addressing fundamental questions about microbial ecology and evolution. We present a comparative analysis of pelagic microbial communities across all five Laurentian Great Lakes, focusing on Bacterial and Archaeal picoplankton characterized via 16S rRNA amplicon sequencing. We collected samples throughout the water column from the major basins of each lake in spring and summer over 2 years. Two oligotypes, classified as LD12 (Alphaproteobacteria) and acI-B1 (Actinobacteria), were among the most abundant in every sample. At the same time, microbial communities showed distinct patterns with depth during summer stratification. Deep hypolimnion samples were frequently dominated by a Chloroflexi oligotype that reached up to 19% relative abundance. Stratified surface communities differed between the colder, less productive upper lakes (Superior, Michigan, Huron) and warmer, more productive lower lakes (Erie, Ontario), in part due to an Actinobacteria oligotype (acI-C2) that averaged 7.7% of sequences in the lower lakes but <0.2% in the upper lakes. Together, our findings suggest that both hydrologic connectivity and local selective pressures shape microbial communities in the Great Lakes and establish a framework for future investigations.


Asunto(s)
Actinobacteria/aislamiento & purificación , Alphaproteobacteria/aislamiento & purificación , Archaea/aislamiento & purificación , Chloroflexi/aislamiento & purificación , Lagos/microbiología , Microbiota/genética , Actinobacteria/clasificación , Actinobacteria/genética , Alphaproteobacteria/clasificación , Alphaproteobacteria/genética , Archaea/clasificación , Archaea/genética , Chloroflexi/clasificación , Chloroflexi/genética , Michigan , Filogenia , Plancton/clasificación , Plancton/genética , ARN Ribosómico 16S/genética
6.
J Immunol ; 201(8): 2215-2219, 2018 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-30209190

RESUMEN

Murine Foxp3+ regulatory T cells (Tregs) differentiated in vitro (induced Tregs [iTregs]) in the presence of anti-inflammatory cytokine TGF-ß rely predominantly upon lipid oxidation to fuel mitochondrial oxidative phosphorylation. Foxp3 expression underlies this metabolic preference, as it suppresses glycolysis and drives oxidative phosphorylation. In this study, we show that in contrast to iTregs, thymic-derived Tregs (tTregs), engage in glycolysis and glutaminolysis at levels comparable to effector T cells despite maintained Foxp3 expression. Interestingly, exposure of tTregs to the anti-inflammatory cytokine TGF-ß represses PI3K-mediated mTOR signaling, inhibits glucose transporter and Hk2 expression, and reprograms their metabolism to favor oxidative phosphorylation. Conversely, replicating the effects of inflammation via elevation of PI3K signaling has minimal effects on tTregs but dramatically enhances the glycolysis of normally oxidative iTregs, resulting in reduction of Foxp3 expression. Collectively, these findings suggest both extrinsic and intrinsic factors govern the unique metabolic signature of Treg subsets.


Asunto(s)
Factores de Transcripción Forkhead/metabolismo , Fosfatidilinositol 3-Quinasa/metabolismo , Subgrupos de Linfocitos T/inmunología , Linfocitos T Reguladores/inmunología , Timo/fisiología , Factor de Crecimiento Transformador beta/metabolismo , Animales , Diferenciación Celular , Células Cultivadas , Reprogramación Celular , Factores de Transcripción Forkhead/genética , Glucólisis , Inmunomodulación , Activación de Linfocitos , Ratones , Ratones Transgénicos , Fosforilación Oxidativa , Transducción de Señal , Serina-Treonina Quinasas TOR/metabolismo
7.
Blood ; 125(5): 852-5, 2015 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-25477498

RESUMEN

Mice with T-cell-specific loss of the tumor suppressor gene PTEN early in T-cell ontogeny develop thymic lymphomas that invariably harbor a reciprocal translocation involving the T-cell receptor α/δ locus and c-myc, t(14;15). In addition to its known function as a lipid phosphatase opposing PI3K signaling, PTEN has also been described as playing a prominent role in promoting genomic stability. As a result, it has been uncertain which one(s) of these 2 separable features were required to block the development of lymphoma. Here, using a conditional model in which T cells selectively express 1 phosphatase-dead PTEN mutant (C124S) and maintain 1 null allele, we show that PTEN phosphatase activity is required for preventing the emergence of a malignant T-cell population harboring t(14;15), thus constituting a critical function of PTEN in preventing lymphomagenesis.


Asunto(s)
Regulación Neoplásica de la Expresión Génica , Linfoma de Células T/genética , Fosfohidrolasa PTEN/genética , Linfocitos T/enzimología , Neoplasias del Timo/genética , Animales , Médula Ósea/enzimología , Médula Ósea/patología , Quimera/genética , Quimera/metabolismo , Cromosomas de los Mamíferos , Linfoma de Células T/enzimología , Linfoma de Células T/patología , Ratones , Ratones Noqueados , Fosfohidrolasa PTEN/deficiencia , Isoformas de Proteínas/deficiencia , Isoformas de Proteínas/genética , Receptores de Antígenos de Linfocitos T alfa-beta/genética , Receptores de Antígenos de Linfocitos T alfa-beta/metabolismo , Receptores de Antígenos de Linfocitos T gamma-delta/genética , Receptores de Antígenos de Linfocitos T gamma-delta/metabolismo , Transducción de Señal , Linfocitos T/patología , Timo/enzimología , Timo/patología , Neoplasias del Timo/enzimología , Neoplasias del Timo/patología , Translocación Genética
9.
Appl Environ Microbiol ; 80(2): 757-65, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24242244

RESUMEN

Gulls are prevalent in beach environments and can be a major source of fecal contamination. Gulls have been shown to harbor a high abundance of fecal indicator bacteria (FIB), such as Escherichia coli and enterococci, which can be readily detected as part of routine beach monitoring. Despite the ubiquitous presence of gull fecal material in beach environments, the associated microbial community is relatively poorly characterized. We generated comprehensive microbial community profiles of gull fecal samples using Roche 454 and Illumina MiSeq platforms to investigate the composition and variability of the gull fecal microbial community and to measure the proportion of FIB. Enterococcaceae and Enterobacteriaceae were the two most abundant families in our gull samples. Sequence comparisons between short-read data and nearly full-length 16S rRNA gene clones generated from the same samples revealed Catellicoccus marimammalium as the most numerous taxon among all samples. The identification of bacteria from gull fecal pellets cultured on membrane-Enterococcus indoxyl-ß-D-glucoside (mEI) plates showed that the dominant sequences recovered in our sequence libraries did not represent organisms culturable on mEI. Based on 16S rRNA gene sequencing of gull fecal isolates cultured on mEI plates, 98.8% were identified as Enterococcus spp., 1.2% were identified as Streptococcus spp., and none were identified as C. marimammalium. Illumina deep sequencing indicated that gull fecal samples harbor significantly higher proportions of C. marimammalium 16S rRNA gene sequences (>50-fold) relative to typical mEI culturable Enterococcus spp. C. marimammalium therefore can be confidently utilized as a genetic marker to identify gull fecal pollution in the beach environment.


Asunto(s)
Charadriiformes/microbiología , Enterococcaceae/genética , Enterococcaceae/aislamiento & purificación , Heces/microbiología , Tracto Gastrointestinal/microbiología , Animales , Técnicas Bacteriológicas , Enterobacteriaceae/genética , Enterobacteriaceae/aislamiento & purificación , Enterococcaceae/clasificación , Monitoreo del Ambiente/métodos , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Lagos , Datos de Secuencia Molecular , Filogenia , ARN Ribosómico 16S , Reproducibilidad de los Resultados , Wisconsin
10.
Microorganisms ; 12(3)2024 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-38543545

RESUMEN

Antibiotic resistance remains one of the most pressing public health issues facing the world today. At the forefront of this battle lies the ever-increasing identification of extended-spectrum beta-lactamases and carbapenemases within human pathogens, conferring resistance towards broad-spectrum and last-resort antimicrobials. This study was prompted due to the identification of a pathogenic Aeromonas hydrophila isolate (strain MAH-4) collected from abdominal fluid, which presented a robust resistance pattern against second-, third-, and fourth-generation cephalosporins, ertapenem, ciprofloxacin, gentamicin, levofloxacin and moxifloxacin, and beta lactam/beta-lactamase inhibitor combinations. Whole genome sequencing was performed and identified a 328 kb plasmid (pMAH4) encoding 10 antibiotic resistance genes, including blaSFO-1, blaTEM-1, and blaOXA-1 of A. hydrophia MAH-4. This is the first report of beta-lactamase SFO-1 within a clinical strain of Aeromonas. Due to the remarkable sequence identity of pMAH4 to plasmids associated with Enterobacterales genera like Klebsiella and the extensive capabilities of Aeromonas for horizontal gene transfer, our identification of a clinical isolate encoding SFO-1 on a plasmid suggests antibiotic resistance gene mobility between Enterobacterales and non-Enterobacterales species.

11.
Water Environ Res ; 96(4): e11021, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38605502

RESUMEN

Anthropogenic particles (AP), which include microplastics and other synthetic, semisynthetic, and anthropogenically modified materials, are pollutants of concern in aquatic ecosystems worldwide. Rivers are important conduits and retention sites for AP, and time series data on the movement of these particles in lotic ecosystems are needed to assess the role of rivers in the global AP cycle. Much research assessing AP pollution extrapolates stream loads based on single time point measurements, but lotic ecosystems are highly variable over time (e.g., seasonality and storm events). The accuracy of models describing AP dynamics in rivers is constrained by the limited studies that examine how frequent changes in discharge drive particle retention and transport. This study addressed this knowledge gap by using automated, high-resolution sampling to track AP concentrations and fluxes during multiple storm events in an urban river (Milwaukee River) and comparing these measurements to commonly monitored water quality metrics. AP concentrations and fluxes varied significantly across four storm events, highlighting the temporal variability of AP dynamics. When data from the sampling periods were pooled, there were increases in particle concentration and flux during the early phases of the storms, suggesting that floods may flush AP into the river and/or resuspend particles from the benthic zone. AP flux was closely linked to river discharge, suggesting large loads of AP are delivered downstream during storms. Unexpectedly, AP concentrations were not correlated with other simultaneously measured water quality metrics, including total suspended solids, fecal coliforms, chloride, nitrate, and sulfate, indicating that these metrics cannot be used to estimate AP. These data will contribute to more accurate models of particle dynamics in rivers and global plastic export to oceans. PRACTITIONER POINTS: Anthropogenic particle (AP) concentrations and fluxes in an urban river varied across four storm events. AP concentrations and fluxes were the highest during the early phases of the storms. Storms increased AP transport downstream compared with baseflow. AP concentrations did not correlate with other water quality metrics during storms.


Asunto(s)
Ecosistema , Contaminantes Químicos del Agua , Plásticos , Calidad del Agua , Ríos , Heces , Monitoreo del Ambiente , Contaminantes Químicos del Agua/análisis
12.
Environ Microbiol ; 15(8): 2213-27, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23438335

RESUMEN

Faecal pollution contains a rich and diverse community of bacteria derived from animals and humans, many of which might serve as alternatives to the traditional enterococci and Escherichia coli faecal indicators. We used massively parallel sequencing (MPS) of the 16S rRNA gene to characterize microbial communities from wastewater treatment plant (WWTP) influent sewage from 12 cities geographically distributed across the USA. We examined members of the Clostridiales, which included the families Clostridiaceae, Lachnospiraceae and Ruminococcaceae for their potential as sewage indicators. Lachnospiraceae was one of the most abundant groups of faecal bacteria in sewage, and several Lachnospiraceae high-abundance sewage pyrotags occurred in at least 46 of 48 human faecal samples. Clone libraries targeting Clostridium coccoides (C. coccoides) in sewage samples demonstrated that Lachnospiraceae-annotated V6 pyrotags encompassed the previously reported C. coccoides group. We used oligotyping to profile the genus Blautia within Lachnospiraceae and found oligotypes comprised of 24 entropy components that showed patterns of host specificity. These findings suggest that indicators based on Blautia might have the capacity to discriminate between different faecal pollution sources. Development of source-specific alternative indicators would enhance water quality assessments, which leads to improved ecosystem health and reduced human health risk due to waterborne disease.


Asunto(s)
Biodiversidad , Monitoreo del Ambiente/normas , Heces/microbiología , Bacterias Grampositivas/fisiología , Aguas del Alcantarillado/microbiología , Animales , Técnicas de Tipificación Bacteriana , Bovinos , Pollos/microbiología , Bacterias Grampositivas/clasificación , Bacterias Grampositivas/genética , Humanos , Datos de Secuencia Molecular , Filogenia , ARN Ribosómico 16S/genética
13.
Appl Environ Microbiol ; 79(9): 2906-13, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23435885

RESUMEN

Microbial sewage communities consist of a combination of human fecal microorganisms and nonfecal microorganisms, which may be residents of urban sewer infrastructure or flowthrough originating from gray water or rainwater inputs. Together, these different microorganism sources form an identifiable community structure that may serve as a signature for sewage discharges and as candidates for alternative indicators specific for human fecal pollution. However, the structure and variability of this community across geographic space remains uncharacterized. We used massively parallel 454 pyrosequencing of the V6 region in 16S rRNA genes to profile microbial communities from 13 untreated sewage influent samples collected from a wide range of geographic locations in the United States. We obtained a total of 380,175 high-quality sequences for sequence-based clustering, taxonomic analyses, and profile comparisons. The sewage profile included a discernible core human fecal signature made up of several abundant taxonomic groups within Firmicutes, Bacteroidetes, Actinobacteria, and Proteobacteria. DNA sequences were also classified into fecal, sewage infrastructure (i.e., nonfecal), and transient groups based on data comparisons with fecal samples. Across all sewage samples, an estimated 12.1% of sequences were fecal in origin, while 81.4% were consistently associated with the sewage infrastructure. The composition of feces-derived operational taxonomic units remained congruent across all sewage samples regardless of geographic locale; however, the sewage infrastructure community composition varied among cities, with city latitude best explaining this variation. Together, these results suggest that untreated sewage microbial communities harbor a core group of fecal bacteria across geographically dispersed wastewater sewage lines and that ambient water quality indicators targeting these select core microorganisms may perform well across the United States.


Asunto(s)
Bacterias/clasificación , Aguas del Alcantarillado/microbiología , Microbiología del Agua , Bacterias/genética , Bacterias/aislamiento & purificación , Bacteroidetes/clasificación , Bacteroidetes/genética , Bacteroidetes/aislamiento & purificación , Biodiversidad , Análisis por Conglomerados , ADN Bacteriano/química , ADN Bacteriano/genética , ADN Ribosómico/química , ADN Ribosómico/genética , Heces/microbiología , Geografía , Secuenciación de Nucleótidos de Alto Rendimiento , ARN Ribosómico 16S/genética , Estados Unidos
14.
Microb Ecol ; 65(4): 1011-23, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23475306

RESUMEN

Urban coasts receive watershed drainage from ecosystems that include highly developed lands with sewer and stormwater infrastructure. In these complex ecosystems, coastal waters are often contaminated with fecal pollution, where multiple delivery mechanisms that often contain multiple fecal sources make it difficult to mitigate the pollution. Here, we exploit bacterial community sequencing of the V6 and V6V4 hypervariable regions of the bacterial 16S rRNA gene to identify bacterial distributions that signal the presence of sewer, fecal, and human fecal pollution. The sequences classified to three sewer infrastructure-associated bacterial genera, Acinetobacter, Arcobacter, and Trichococcus, and five fecal-associated bacterial families, Bacteroidaceae, Porphyromonadaceae, Clostridiaceae, Lachnospiraceae, and Ruminococcaceae, served as signatures of sewer and fecal contamination, respectively. The human fecal signature was determined with the Bayesian source estimation program SourceTracker, which we applied to a set of 40 sewage influent samples collected in Milwaukee, WI, USA to identify operational taxonomic units (≥ 97 % identity) that were most likely of human fecal origin. During periods of dry weather, the magnitudes of all three signatures were relatively low in Milwaukee's urban rivers and harbor and nearly zero in Lake Michigan. However, the relative contribution of the sewer and fecal signature frequently increased to > 2 % of the measured surface water communities following sewer overflows. Also during combined sewer overflows, the ratio of the human fecal pollution signature to the fecal pollution signature in surface waters was generally close to that of sewage, but this ratio decreased dramatically during dry weather and rain events, suggesting that nonhuman fecal pollution was the dominant source during these weather-driven scenarios. The qPCR detection of two human fecal indicators, human Bacteroides and Lachno2, confirmed the urban fecal footprint in this ecosystem extends to at least 8 km offshore.


Asunto(s)
Bacterias/aislamiento & purificación , Heces/química , Lagos/microbiología , Contaminación del Agua/análisis , Bacterias/clasificación , Bacterias/genética , ADN Bacteriano/genética , Ecosistema , Monitoreo del Ambiente , Humanos , Michigan , ARN Ribosómico 16S/genética , Aguas del Alcantarillado/análisis , Aguas del Alcantarillado/microbiología , Urbanización
15.
J Immunol ; 186(2): 940-50, 2011 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-21148796

RESUMEN

DRAK2 is a serine/threonine kinase highly enriched in lymphocytes that raises the threshold for T cell activation and maintains T cell survival following productive activation. T cells lacking DRAK2 are prone to activation under suboptimal conditions and exhibit enhanced calcium responses to AgR stimulation. Despite this, mice lacking DRAK2 are resistant to organ-specific autoimmune diseases due to defective autoreactive T cell survival. DRAK2 kinase activity is induced by AgR signaling, and in this study we show that the induction of DRAK2 activity requires Ca(2+) influx through the Ca(2+) release-activated Ca(2+) channel formed from Orai1 subunits. Blockade of DRAK2 activity with the protein kinase D (PKD) inhibitor Gö6976 or expression of a kinase-dead PKD mutant prevented activation of DRAK2, whereas a constitutively active PKD mutant promoted DRAK2 function. Knockdown of PKD in T cells strongly blocked endogenous DRAK2 activation following TCR ligation, implicating PKD as an essential intermediate in the activation of DRAK2 by Ca(2+) influx. Furthermore, we identify DRAK2 as a novel substrate of PKD, and demonstrate that DRAK2 and PKD physically interact under conditions that activate PKD. Mitochondrial generation of reactive oxygen intermediates was necessary and sufficient for DRAK2 activation in response to Ca(2+) influx. Taken together, DRAK2 and PKD form a novel signaling module that controls calcium homeostasis following T cell activation.


Asunto(s)
Proteínas Reguladoras de la Apoptosis/metabolismo , Señalización del Calcio/inmunología , Mitocondrias/inmunología , Mitocondrias/metabolismo , Proteína Quinasa C/fisiología , Proteínas Serina-Treonina Quinasas/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Receptores de Antígenos de Linfocitos T/fisiología , Animales , Proteínas Reguladoras de la Apoptosis/deficiencia , Proteínas Reguladoras de la Apoptosis/genética , Señalización del Calcio/genética , Células Clonales , Activación Enzimática/genética , Activación Enzimática/inmunología , Homeostasis/genética , Homeostasis/inmunología , Humanos , Células Jurkat , Activación de Linfocitos/genética , Activación de Linfocitos/inmunología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Transgénicos , Proteínas Serina-Treonina Quinasas/deficiencia , Proteínas Serina-Treonina Quinasas/genética , Linfocitos T/enzimología , Linfocitos T/inmunología
16.
Water Environ Res ; 95(4): e10856, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36949613

RESUMEN

Activated sludge is a conventional treatment process for biochemical oxygen demand (BOD) and total suspended solids (TSS) removal at water resource recovery facilities (WRRFs). Foaming events are a common operational issue in activated sludge and can lead to decreased treatment efficiency, maintenance issues, and potential environmental health risks. Stable foaming events are caused by biological and chemical drivers (i.e., microbes and surfactants) during the aeration process. However, foaming events are difficult to predict and quantify. We present an inexpensive and easy-to-use method that can be applied at WRRFs to quantify foaming potential. Subsequently, the method was applied over a year-long full-scale study while data on microbial community composition and functional parameters associated with foaming potential were collected from activated sludge samples at South Shore Water Reclamation Facility (WRF) (Oak Creek, WI). Results from the development of the foaming potential method using linear alkylbenzene sulfonate (LAS) showed that the method was reproducible (relative standard deviation <20%) and able to capture changes in foam-inducing constituents. Using full-scale activated sludge samples, higher relative abundance values for the following genera were associated with foaming events: Zoogloea, Flavobacterium, Variovorax, and Bdellovibrio. This is the first report that Variovorx and Bdellovibrio relative abundance was correlated with foaming events in activated sludge. Furthermore, the foaming potential positively correlated (ρ = 0.24) with soluble total nitrogen. Characterizing foaming events through frequent sampling and monitoring of specific genera and functional parameters may allow for predictions and preemptive mitigation efforts to avoid negative consequences in the future. PRACTITIONER POINTS: A reproducible method to measure foaming potential in activated sludge is available. Genera Zoogloea, Flavobacterium, Variovorax, and Bdellovibrio correlated with foaming events. A year-long sampling campaign of activated sludge measuring foaming potential and microbial community composition was conducted at South Shore Water Reclamation Facility in Oak Creek, WI. More research at other facilities with this method is needed to understand links between microbes and foaming.


Asunto(s)
Microbiota , Purificación del Agua , Aguas del Alcantarillado/química , Eliminación de Residuos Líquidos/métodos , Nitrógeno , Agua , Reactores Biológicos
17.
Vaccine ; 41(5): 1153-1160, 2023 01 27.
Artículo en Inglés | MEDLINE | ID: mdl-36621408

RESUMEN

BACKGROUND: Immunogenicity and safety up to 5 years after administration of 1 or 2 doses of quadrivalent meningococcal serogroup A, C, W, and Y tetanus toxoid conjugate vaccine (MenACWY-TT) given alone or with 13-valent pneumococcal conjugate vaccine (PCV13) in children was investigated. METHODS: This phase 3 study randomized healthy 12-24-month-olds to MenACWY-TT at Month 0 (ACWY1d), MenACWY-TT at Months 0 and 2 (ACWY2d), MenACWY-TT and PCV13 at Month 0 (Co-Ad), or PCV13 at Month 0 and MenACWY-TT at Month 2 (PCV13/ACWY). Immune responses 1, 3, and 5 years after primary vaccination were evaluated with serum bactericidal activity using rabbit complement (rSBA) titers ≥ 1:8 and geometric mean titers (GMTs). Evaluation of serious adverse events up to 5 years after primary vaccination are reported. RESULTS: Of the 802 children randomized in the study, 619 completed the study through Year 5. Immune responses after vaccination declined over time but were higher 5 years after vaccination compared with levels before vaccination. At Year 5, the percentages of children with rSBA titers ≥ 1:8 across all serogroups were 20.5 %-58.6 %, 28.4 %-65.8 %, 23.9 %-52.8 %, and 19.4 %-55.8 % in the ACWY1d, ACWY2d, Co-Ad, and PCV13/ACWY groups, respectively. Comparable antibody persistence at Year 5 was observed for participants receiving 1 or 2 doses of MenACWY-TT, although GMTs were elevated in those who received 2 versus 1 dose. The percentage of children with protective antibody titers at Year 5 was similar in participants who received PCV13 and MenACWY-TT compared with that observed for participants who only received 1 or 2 MenACWY-TT doses. No new safety concerns were identified during the study period. CONCLUSION: Antibody responses persisted in the majority of children up to 5 years after primary vaccination with MenACWY-TT administered in a 1- or 2-dose regimen with or without PCV13, with no new safety concerns identified. CLINICALTRIALS: gov Identifier NCT01939158; EudraCT number 2013-001083-28.


Asunto(s)
Infecciones Meningocócicas , Vacunas Meningococicas , Neisseria meningitidis , Humanos , Vacunas Conjugadas/efectos adversos , Anticuerpos Antibacterianos , Toxoide Tetánico , Infecciones Meningocócicas/prevención & control
18.
mSphere ; 8(5): e0030723, 2023 10 24.
Artículo en Inglés | MEDLINE | ID: mdl-37681947

RESUMEN

Corrosion inhibitors, including zinc orthophosphate, sodium orthophosphate, and sodium silicate, are commonly used to prevent the corrosion of drinking water infrastructure. Metals such as zinc are known stressors for antibiotic resistance selection, and phosphates can increase microbial growth in drinking water distribution systems (DWDS). Yet, the influence of corrosion inhibitor type on antimicrobial resistance in DWDS is unknown. Here, we show that sodium silicates can decrease antibiotic resistant bacteria (ARB) and antibiotic-resistance genes (ARGs), while zinc orthophosphate increases ARB and ARGs in source water microbial communities. Based on controlled bench-scale studies, zinc orthophosphate addition significantly increased the abundance of ARB resistant to ciprofloxacin, sulfonamides, trimethoprim, and vancomycin, as well as the genes sul1, qacEΔ1, an indication of resistance to quaternary ammonium compounds, and the integron-integrase gene intI1. In contrast, sodium silicate dosage at 10 mg/L resulted in decreased bacterial growth and antibiotic resistance selection compared to the other corrosion inhibitor additions. Source water collected from the drinking water treatment plant intake pipe resulted in less significant changes in ARB and ARG abundance due to corrosion inhibitor addition compared to source water collected from the pier at the recreational beach. In tandem with the antibiotic resistance shifts, significant microbial community composition changes also occurred. Overall, the corrosion inhibitor sodium silicate resulted in the least selection for antibiotic resistance, which suggests it is the preferred corrosion inhibitor option for minimizing antibiotic resistance proliferation in DWDS. However, the selection of an appropriate corrosion inhibitor must also be appropriate for the water chemistry of the system (e.g., pH, alkalinity) to minimize metal leaching first and foremost and to adhere to the lead and copper rule. IMPORTANCE Antibiotic resistance is a growing public health concern across the globe and was recently labeled the silent pandemic. Scientists aim to identify the source of antibiotic resistance and control points to mitigate the spread of antibiotic resistance. Drinking water is a direct exposure route to humans and contains antibiotic-resistant bacteria and associated resistance genes. Corrosion inhibitors are added to prevent metallic pipes in distribution systems from corroding, and the type of corrosion inhibitor selected could also have implications on antibiotic resistance. Indeed, we found that sodium silicate can minimize selection of antibiotic resistance while phosphate-based corrosion inhibitors can promote antibiotic resistance. These findings indicate that sodium silicate is a preferred corrosion inhibitor choice for mitigation of antibiotic resistance.


Asunto(s)
Agua Potable , Microbiota , Humanos , Corrosión , Antagonistas de Receptores de Angiotensina , Inhibidores de la Enzima Convertidora de Angiotensina , Farmacorresistencia Microbiana/genética , Zinc , Antibacterianos/farmacología , Fosfatos , Sodio
19.
Int J Antimicrob Agents ; 62(2): 106848, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37201798

RESUMEN

Antimicrobial resistance (AMR) is one of the most pressing public health concerns; therefore, it is imperative to advance our understanding of the factors influencing AMR from Global and One Health perspectives. To address this, Aeromonas populations were identified using 16S rRNA gene libraries among human, agriculture, aquaculture, drinking water, surface water, and wastewater samples, supporting its use as indicator bacteria to study AMR. A systematic review and meta-analysis was then performed from Global and One Health perspectives, including data from 221 articles describing 15 891 isolates from 57 countries. The interconnectedness of different environments was evident as minimal differences were identified between sectors among 21 different antimicrobials. However, resistance to critically important antibiotics (aztreonam and cefepime) was significantly higher among wastewater populations compared with clinical isolates. Additionally, isolates from untreated wastewater typically exhibited increased AMR compared with those from treated wastewater. Furthermore, aquaculture was associated with increased AMR to ciprofloxacin and tetracycline compared with wild-caught seafood. Using the World Health Organization AWaRe classifications, countries with lower consumption of "Access" compared to "Watch" drugs from 2000 to 2015 demonstrated higher AMR levels. The current analysis revealed negative correlations between AMR and anthropogenic factors, such as environmental performance indices and socioeconomic standing. Environmental health and sanitation were two of the environmental factors most strongly correlated with AMR. The current analysis highlights the negative impacts of "Watch" drug overconsumption, anthropogenic activity, absence of wastewater infrastructure, and aquaculture on AMR, thus stressing the need for proper infrastructure and global regulations to combat this growing problem.


Asunto(s)
Aeromonas , Antiinfecciosos , Salud Única , Humanos , Aeromonas/genética , Aguas Residuales , Salud Global , ARN Ribosómico 16S , Farmacorresistencia Bacteriana , Antibacterianos/farmacología
20.
Microbiol Resour Announc ; 11(7): e0031922, 2022 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-35727055

RESUMEN

Wastewater microbiome research often relies on sequencing of hypervariable regions of 16S rRNA genes, which are difficult to classify at refined taxonomic levels. Here, we introduce a data set of near-full-length 16S rRNA genes from samples designed to capture known geographic and seasonal variations in municipal wastewater microbial communities.

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