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1.
Blood Adv ; 2024 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-38991137

RESUMEN

Children and adults with sickle cell disease (SCD) have increases in morbidity and mortality with COVID-19 infections. The ASH Research Collaborative Sickle Cell Disease Research Network performed a prospective COVID-19 vaccine study to assess antibody responses and analyze whether mRNA vaccination precipitated any adverse effects unique to individuals with SCD. Forty-one participants received two doses of the Pfizer-BioNTech vaccine and provided baseline blood samples prior to vaccination and 2 months after the initial vaccination for analysis of IgG reactivity against the receptor binding domain (RBD) of the SARS-CoV-2 spike protein. Six month IgG reactivity against the viral RBD was also available in 37 patients. Post-vaccination reactogenicity was common and similar to the general population. There were no fevers that required inpatient admission. Vaso-occlusive pain within 2-3 days of 1st or 2nd vaccination was reported by 5 (12%) participants including 4 (10%) who sought medical care. Twenty-seven participants (66%) were seropositive at baseline, and all 14 (34%) initially seronegative participants converted to seropositive post vaccination. Overall, mRNA vaccination had a good risk benefit-profile in individuals with sickle cell disease.This mRNA vaccine study also marks the first evaluation of vaccine safety and antibody response in very young children with sickle cell disease. NCT05139992.

2.
Water Res ; 254: 121426, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38471203

RESUMEN

Naegleria fowleri has been detected in drinking water distribution systems (DWDS) in Australia, Pakistan and the United States and is the causative agent of the highly fatal disease primary amoebic meningoencephalitis. Previous small scale field studies have shown that Meiothermus may be a potential biomarker for N. fowleri. However, correlations between predictive biomarkers in small sample sizes often breakdown when applied to larger more representative datasets. This study represents one of the largest and most rigorous temporal investigations of Naegleria fowleri colonisation in an operational DWDS in the world and measured the association of Meiothermus and N. fowleri over a significantly larger space and time in the DWDS. A total of 232 samples were collected from five sites over three-years (2016-2018), which contained 29 positive N. fowleri samples. Two specific operational taxonomic units assigned to M. chliarophilus and M. hypogaeus, were significantly associated with N. fowleri presence. Furthermore, inoculation experiments demonstrated that Meiothermus was required to support N. fowleri growth in field-collected biofilms. This validates Meiothermus as prospective biological tool to aid in the identification and surveillance of N. fowleri colonisable sites.


Asunto(s)
Agua Potable , Naegleria fowleri , Estudios Prospectivos , Bacterias , Biopelículas
3.
ACS ES T Water ; 4(2): 628-637, 2024 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-38356928

RESUMEN

The free-living thermophilic amoeba Naegleria fowleri (N. fowleri) causes the highly fatal disease primary amoebic meningoencephalitis. The environmental conditions that are favorable to the growth and proliferation of N. fowleri are not well-defined, especially in northern regions of the United States. In this study, we used culture-based methods and multiple molecular approaches to detect and analyzeN. fowleri and other Naegleria spp. in water, sediment, and biofilm samples from five hot spring sites in Grand Teton National Park, Wyoming, U.S.A. These results provide the first detections of N. fowleri in Grand Teton National Park and provide new insights into the distribution of pathogenic N. fowleri and other nonpathogenic Naegleria spp. in natural thermal water systems in northern latitudes.

4.
mBio ; 15(3): e0173523, 2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38345372

RESUMEN

Biogenic methane in subsurface coal seam environments is produced by diverse consortia of microbes. Although this methane is useful for global energy security, it remains unclear which microbes can liberate carbon from the coal. Most of this carbon is relatively resistant to biodegradation, as it is contained within aromatic rings. Thus, to explore for coal-degrading taxa in the subsurface, this study reconstructed relevant metagenome-assembled genomes (MAGs) from coal seams by using a key genomic marker for the anaerobic degradation of monoaromatic compounds as a guide: the benzoyl-CoA reductase gene (bcrABCD). Three MAGs were identified with this genetic potential. The first represented a novel taxon from the Krumholzibacteriota phylum, which this study is the first to describe. This Krumholzibacteriota MAG contained a full set of genes for benzoyl-CoA dearomatization, in addition to other genes for anaerobic catabolism of monoaromatics. Analysis of Krumholzibacteriota MAGs from other environments revealed that this genetic potential may be common, and thus, Krumholzibacteriota may be important organisms for the liberation of recalcitrant carbon in a broad range of environments. Moreover, the assembly and characterization of two Syntrophorhabdus aromaticivorans MAGs from different continents and a Syntrophaceae sp. MAG implicate the Deltaproteobacteria class in coal seam monoaromatic degradation. Each of these taxa are potential rate-limiting organisms for subsurface coal-to-methane biodegradation. Their description here provides some understanding of their function within the coal seam microbiome and will help inform future efforts in coal bed methane stimulation, anoxic bioremediation of organic pollutants, and assessments of anoxic, subsurface carbon cycling and emissions.IMPORTANCESubsurface coal seams are highly anoxic, oligotrophic environments, where the main source of carbon is "locked away" within aromatic rings. Despite these challenges, many coal seams accumulate biogenic methane, implying that the coal seam microbiome is "unlocking" this carbon source in situ. For over two decades, researchers have endeavored to understand which organisms perform these processes. This study provides the first descriptions of organisms with this genetic potential from the coal seam environment. Here, we report metagenomic insights into carbon liberation from aromatic molecules and the degradation pathways involved and describe a Krumholzibacteriota, two Syntrophorhabdus aromaticivorans, and a Syntrophaceae MAG that contain this genetic potential. This is also the first time that the Krumholzibacteriota phylum has been implicated in anaerobic dearomatization of aromatic hydrocarbons. This potential is identified here in numerous MAGs from other terrestrial and marine subsurface habitats, implicating the Krumholzibacteriota in carbon-cycling processes across a broad range of environments.


Asunto(s)
Carbón Mineral , Deltaproteobacteria , Carbón Mineral/microbiología , Carbono/metabolismo , Metano/metabolismo , Deltaproteobacteria/metabolismo
5.
J Endocrinol ; 258(2)2023 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-37171828

RESUMEN

Historic and emerging studies provide evidence for the deterioration of pancreatic α cell function and identity in diabetes mellitus. Increased access to human tissue and the availability of more sophisticated molecular technologies have identified key insights into how α cell function and identity are preserved in healthy conditions and how they become dysfunctional in response to stress. These studies have revealed evidence of impaired glucagon secretion, shifts in α cell electrophysiology, changes in α cell mass, dysregulation of α cell transcription, and α-to-ß cell conversion prior to and during diabetes. In this review, we outline the current state of research on α cell identity in health and disease. Evidence in model organisms and humans suggests that in addition to ß cell dysfunction, diabetes is associated with a fundamental dysregulation of α cell identity. Importantly, epigenetic studies have revealed that α cells retain more poised and open chromatin at key cell-specific and diabetes-dysregulated genes, supporting the model that the inherent epigenetic plasticity of α cells makes them susceptible to the transcriptional changes that potentiate the loss of identity and function seen in diabetes. Thus, additional research into the maintenance of α cell identity and function is critical to fully understanding diabetes. Furthermore, these studies suggest α cells could represent an alternative source of new ß cells for diabetes treatment.


Asunto(s)
Diabetes Mellitus Tipo 2 , Células Secretoras de Glucagón , Células Secretoras de Insulina , Humanos , Diabetes Mellitus Tipo 2/genética , Células Secretoras de Insulina/fisiología , Diferenciación Celular
6.
Naturwissenschaften ; 110(3): 20, 2023 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-37199869

RESUMEN

Even for animals with multiple senses at their disposal, there may be a strong reliance on a single sense, like vision, for social behavior. Experimentally blocking or eliminating vision offers a powerful means of testing impacts on social behavior, though few studies have followed experimentally blinded individuals in the wild to test potential changes in social behavior in natural settings. Here we conducted experiments with social hermit crabs (Coenobita compressus), applying opaque material overtop their eyes to temporarily blind individuals. We then released these experimentally blinded individuals and non-blinded control individuals into the wild as well as into captive social settings. Compared to control individuals, experimentally blinded individuals initiated significantly fewer social contacts with conspecifics in the wild. These experimentally blinded individuals were not, however, differentially targeted by conspecifics. Interestingly, unlike the wild experiments, the captive experiments showed no differences in social behavior between experimentally blinded and non-blinded control individuals, suggesting that experiments in natural settings in the wild may be essential to fully unraveling impacts of blindness on social behavior. Broadly, for social animals that are highly reliant on the visual modality, social behavior may change dramatically if they lose their vision.


Asunto(s)
Anomuros , Animales , Conducta Social , Visión Ocular
7.
Hematol Oncol Clin North Am ; 37(2): 393-411, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36907611

RESUMEN

Because women with transfusion-dependent thalassemia are seeking pregnancy, ensuring the best outcomes for both mother and baby require concerted and collaborative efforts between the hematologist, obstetrician, cardiologist, hepatologist, and genetic counselor among others. Proactive counseling, early fertility evaluation, optimal management of iron overload and organ function, and application of advances in reproductive technology and prenatal screening are important in ensuring a healthy outcome. Many unanswered questions remain requiring further study, including fertility preservation, non-invasive prenatal diagnosis, chelation therapy during pregnancy, and indications and duration of anticoagulation.


Asunto(s)
Sobrecarga de Hierro , Talasemia , Talasemia beta , Embarazo , Femenino , Humanos , Talasemia/terapia , Sobrecarga de Hierro/etiología , Terapia por Quelación/efectos adversos , Diagnóstico Prenatal/efectos adversos , Fertilidad , Quelantes del Hierro/uso terapéutico , Talasemia beta/terapia
8.
Exp Biol Med (Maywood) ; 248(10): 897-907, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36941786

RESUMEN

Intravascular hemolysis results in the release of cell-free hemoglobin and heme in plasma. In sickle cell disease, the fragility of the sickle red blood cell leads to chronic hemolysis, which can contribute to oxidative damage and activation of inflammatory pathways. The scavenger proteins haptoglobin and hemopexin provide pathways to remove hemoglobin and heme, respectively, from the circulation. Heme also intercalates in membranes of blood cells and endothelial cells in the vasculature and associates with other plasma components such as albumin and lipoproteins. Hemopexin has a much higher affinity and can strip heme from the other pools and detoxify plasma from cell-free circulatory heme. However, due to chronic hemolysis, hemopexin is depleted in individuals with sickle cell disease. Thus, cell-free unbound heme is expected to accumulate in plasma. We developed a methodology for the accurate quantification of the fraction of heme, which is pathologically relevant in sickle cell disease, that does not appear to be sequestered to a plasma compartment. Our data show significant variation in the concentration of unbound heme, and rather unexpectedly, the size of the unbound fraction does not correlate to the degree of hemolysis, as measured by the concentration of bound heme. Very high heme concentrations (>150 µM) were obtained in some plasma with unbound concentrations that were several fold lower than in plasma with much lower hemolysis (<50 µM). These findings underscore the long-term effects of chronic hemolysis on the blood components and of the disruption of the essential equilibrium between release of hemoproteins/heme in the circulation and adaptative response of the scavenging/removal mechanisms. Understanding the clinical implications of this loss of response may provide insights into diagnostic and therapeutic targets in patients with sickle cell disease.


Asunto(s)
Anemia de Células Falciformes , Hemo , Humanos , Hemólisis , Hemopexina/metabolismo , Hemopexina/farmacología , Hemopexina/uso terapéutico , Células Endoteliales/metabolismo , Anemia de Células Falciformes/tratamiento farmacológico , Hemoglobinas
9.
Front Microbiol ; 14: 1097500, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36970672

RESUMEN

The addition of small amounts of algal biomass to stimulate methane production in coal seams is a promising low carbon renewable coalbed methane enhancement technique. However, little is known about how the addition of algal biomass amendment affects methane production from coals of different thermal maturity. Here, we show that biogenic methane can be produced from five coals ranging in rank from lignite to low-volatile bituminous using a coal-derived microbial consortium in batch microcosms with and without algal amendment. The addition of 0.1 g/l algal biomass resulted in maximum methane production rates up to 37 days earlier and decreased the time required to reach maximum methane production by 17-19 days when compared to unamended, analogous microcosms. Cumulative methane production and methane production rate were generally highest in low rank, subbituminous coals, but no clear association between increasing vitrinite reflectance and decreasing methane production could be determined. Microbial community analysis revealed that archaeal populations were correlated with methane production rate (p = 0.01), vitrinite reflectance (p = 0.03), percent volatile matter (p = 0.03), and fixed carbon (p = 0.02), all of which are related to coal rank and composition. Sequences indicative of the acetoclastic methanogenic genus Methanosaeta dominated low rank coal microcosms. Amended treatments that had increased methane production relative to unamended analogs had high relative abundances of the hydrogenotrophic methanogenic genus Methanobacterium and the bacterial family Pseudomonadaceae. These results suggest that algal amendment may shift coal-derived microbial communities towards coal-degrading bacteria and CO2-reducing methanogens. These results have broad implications for understanding subsurface carbon cycling in coal beds and the adoption of low carbon renewable microbially enhanced coalbed methane techniques across a diverse range of coal geology.

10.
Anaesthesia ; 78(3): 330-336, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36709511

RESUMEN

This multidisciplinary consensus statement was produced following a recommendation by the Faculty of Intensive Care Medicine to develop a UK guideline for ancillary investigation, when one is required, to support the diagnosis of death using neurological criteria. A multidisciplinary panel reviewed the literature and UK practice in the diagnosis of death using neurological criteria and recommended cerebral CT angiography as the ancillary investigation of choice when death cannot be confirmed by clinical criteria alone. Cerebral CT angiography has been shown to have 100% specificity in supporting a diagnosis of death using neurological criteria and is an investigation available in all acute hospitals in the UK. A standardised technique for performing the investigation is described alongside a reporting template. The panel were unable to make recommendations for ancillary testing in children or patients receiving extracorporeal membrane oxygenation.


Asunto(s)
Muerte Encefálica , Angiografía por Tomografía Computarizada , Niño , Humanos , Muerte Encefálica/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Angiografía Cerebral/métodos , Circulación Cerebrovascular
11.
Lancet ; 400(10351): 493-501, 2022 08 13.
Artículo en Inglés | MEDLINE | ID: mdl-35964609

RESUMEN

BACKGROUND: Patients with non-transfusion-dependent thalassaemia (NTDT), although they do not require regular blood transfusions for survival, can still accrue a heavy burden of comorbidities. No approved disease-modifying therapies exist for these patients. We aimed to investigate the safety and efficacy of mitapivat (Agios Pharmaceuticals, Cambridge, MA, USA), a pyruvate kinase activator, in adults with non-transfusion-dependent (NTD) α-thalassaemia or NTD ß-thalassaemia. METHODS: In this open-label, multicentre, phase 2 study, patients were recruited from four academic clinical study sites in Oakland, CA, and Boston, MA, USA; Toronto, ON, Canada; and London, UK. Patients were eligible if they were aged 18 years or older, with NTDT (including ß-thalassaemia with or without α-globin gene mutations, haemoglobin E ß-thalassaemia, or α-thalassaemia), and a baseline haemoglobin concentration of 10·0 g/dL or lower. During a 24-week core period, mitapivat was administered orally at 50 mg twice daily for the first 6 weeks followed by an escalation to 100 mg twice daily for 18 weeks thereafter. The primary endpoint was haemoglobin response (a ≥1·0 g/dL increase in haemoglobin concentration from baseline at one or more assessments between weeks 4 and 12). Efficacy and safety were assessed in the full analysis set (ie, all patients who received at least one dose of study drug). This study is registered with ClinicalTrials.gov, NCT03692052, and is closed to accrual. FINDINGS: Between Dec 28, 2018, and Feb 6, 2020, 27 patients were screened, of whom 20 were enrolled (15 [75%] with ß-thalassaemia and five [25%] with α-thalassaemia) and received mitapivat. The median age of patients was 44 years (IQR 35-56), 15 (75%) of 20 patients were female, five (25%) were male, and ten (50%) identified as Asian. 16 (80% [90% CI 60-93]) of 20 patients had a haemoglobin response (p<0·0001), five (100%) of five with α-thalassaemia and 11 (73%) of 15 with ß-thalassaemia. 17 (85%) patients had a treatment-emergent adverse event, and 13 had a treatment-emergent event that was considered to be treatment related. One serious treatment-emergent adverse event occurred (grade 3 renal impairment), which was considered unrelated to study drug, resulting in discontinuation of treatment. The most commonly reported treatment-emergent adverse events were initial insomnia (ten [50%] patients), dizziness (six [30%]), and headache (five [25%]). No patients died during the 24-week core period. INTERPRETATION: These efficacy and safety results support the continued investigation of mitapivat for the treatment of both α-thalassaemia and ß-thalassaemia. FUNDING: Agios Pharmaceuticals.


Asunto(s)
Piperazinas , Quinolinas , Talasemia alfa , Talasemia beta , Adulto , Femenino , Hemoglobinas , Humanos , Masculino , Persona de Mediana Edad , Piperazinas/efectos adversos , Piruvato Quinasa , Quinolinas/efectos adversos , Talasemia alfa/tratamiento farmacológico , Talasemia beta/tratamiento farmacológico
12.
Environ Microbiol ; 24(9): 4065-4078, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35437913

RESUMEN

The production of methane as an end-product of organic matter degradation in the absence of other terminal electron acceptors is common, and has often been studied in environments such as animal guts, soils and wetlands due to its potency as a greenhouse gas. To date, however, the study of the biogeographic distribution of methanogens across coal seam environments has been minimal. Here, we show that coal seams are host to a diverse range of methanogens, which are distinctive to each geological basin. Based on comparisons to close relatives from other methanogenic environments, the dominant methanogenic pathway in these basins is hydrogenotrophic, with acetoclastic being a second major pathway in the Surat Basin. Finally, mcrA and 16S rRNA gene primer biases were predominantly seen to affect the detection of Methanocellales, Methanomicrobiales and Methanosarcinales taxa in this study. Subsurface coal methanogenic community distributions and pathways presented here provide insights into important metabolites and bacterial partners for in situ coal biodegradation.


Asunto(s)
Euryarchaeota , Gases de Efecto Invernadero , Animales , Archaea/metabolismo , Carbón Mineral/microbiología , Euryarchaeota/genética , Gases de Efecto Invernadero/metabolismo , Metano/metabolismo , Filogenia , ARN Ribosómico 16S/genética , ARN Ribosómico 16S/metabolismo , Suelo
13.
NPJ Biofilms Microbiomes ; 8(1): 7, 2022 02 17.
Artículo en Inglés | MEDLINE | ID: mdl-35177633

RESUMEN

Environmentally relevant metagenomes and BONCAT-FACS derived translationally active metagenomes from Powder River Basin coal seams were investigated to elucidate potential genes and functional groups involved in hydrocarbon degradation to methane in coal seams with high- and low-sulfate levels. An advanced subsurface environmental sampler allowed the establishment of coal-associated microbial communities under in situ conditions for metagenomic analyses from environmental and translationally active populations. Metagenomic sequencing demonstrated that biosurfactants, aerobic dioxygenases, and anaerobic phenol degradation pathways were present in active populations across the sampled coal seams. In particular, results suggested the importance of anaerobic degradation pathways under high-sulfate conditions with an emphasis on fumarate addition. Under low-sulfate conditions, a mixture of both aerobic and anaerobic pathways was observed but with a predominance of aerobic dioxygenases. The putative low-molecular-weight biosurfactant, lichysein, appeared to play a more important role compared to rhamnolipids. The methods used in this study-subsurface environmental samplers in combination with metagenomic sequencing of both total and translationally active metagenomes-offer a deeper and environmentally relevant perspective on community genetic potential from coal seams poised at different redox conditions broadening the understanding of degradation strategies for subsurface carbon.


Asunto(s)
Carbón Mineral , Microbiota , Metagenómica , Metano , Sulfatos
14.
Environ Sci Technol ; 56(5): 3225-3233, 2022 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-35142487

RESUMEN

Subsurface microbial (biogenic) methane production is an important part of the global carbon cycle that has resulted in natural gas accumulations in many coal beds worldwide. Laboratory studies suggest that complex carbon-containing nutrients (e.g., yeast or algae extract) can stimulate methane production, yet the effectiveness of these nutrients within coal beds is unknown. Here, we use downhole monitoring methods in combination with deuterated water (D2O) and a 200-liter injection of 0.1% yeast extract (YE) to stimulate and isotopically label newly generated methane. A total dissolved gas pressure sensor enabled real-time gas measurements (641 days preinjection and for 478 days postinjection). Downhole samples, collected with subsurface environmental samplers, indicate that methane increased 132% above preinjection levels based on isotopic labeling from D2O, 108% based on pressure readings, and 183% based on methane measurements 266 days postinjection. Demonstrating that YE enhances biogenic coalbed methane production in situ using multiple novel measurement methods has immediate implications for other field-scale biogenic methane investigations, including in situ methods to detect and track microbial activities related to the methanogenic turnover of recalcitrant carbon in the subsurface.


Asunto(s)
Carbón Mineral , Metano , Carbono , Gas Natural
15.
Complement Ther Med ; 64: 102803, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35032556

RESUMEN

OBJECTIVES: L-Glutamine is FDA-approved for sickle cell disease (SCD), yet the mechanism(s)-of-action are poorly understood. We performed a pharmacokinetics (pK) study to determine the metabolic fate of glutamine supplementation on plasma and erythrocyte amino acids in patients with SCD. DESIGN: A pK study was performed where patients with SCD fasting for > 8 h received oral L-glutamine (10 g). Blood was analyzed at baseline, 30/60/90 min/2/3/4/8 hrs. A standardized diet was administered to all participants at 3 established time-points (after 2/5/7hrs). A subset of patients also had pK studies performed without glutamine supplementation to follow normal diurnal fluctuations in amino acids. SETTING: Comprehensive SCD Center in Oakland, California RESULTS: Five patients with SCD were included, three of whom performed pK studies both with and without glutamine supplementation. Average age was 50.6 ± 5.6 years, 60% were female, 40% SS, 60% SC. Plasma glutamine levels increased significantly after oral glutamine supplementation, compared to minimal fluctuations with diet. Plasma glutamine concentration peaked within 30-min of ingestion (p = 0.01) before decreasing to a plateau by 2-h that remained higher than baseline by 8 h. Oral glutamine also increased plasma arginine concentration, which peaked by 4-h (p = 0.03) and remained elevated through 8-h. Erythrocyte glutamine levels began to increase by 8-h, while erythrocyte arginine concentration peaked at 4-h. CONCLUSIONS: Oral glutamine supplementation acutely improved glutamine and arginine bioavailability in both plasma and erythrocytes. This is the first study to demonstrate that glutamine therapy increases arginine bioavailability and may provide insight into shared mechanisms-of-action between these conditionally-essential amino acids.


Asunto(s)
Anemia de Células Falciformes , Glutamina , Aminoácidos , Anemia de Células Falciformes/tratamiento farmacológico , Suplementos Dietéticos , Eritrocitos , Femenino , Humanos , Persona de Mediana Edad
16.
Anal Chem ; 94(2): 1092-1100, 2022 01 18.
Artículo en Inglés | MEDLINE | ID: mdl-34967622

RESUMEN

Stable hydrogen isotope compositions (2H/1H ratios) have been an invaluable tool for studying biogeochemical processes in nature, but the diversity of molecular targets amenable to such analysis is limited. Here, we demonstrate a new technique for measuring δ2H of biomolecules via Orbitrap mass spectrometry (MS) using acetate as a model analyte. Acetate was chosen as a target molecule because its production and consumption are central to microbial carbon cycling, yet the mechanisms behind acetate turnover remain poorly understood. δ2H of acetate could provide a useful constraint on these processes; however, it remains uncharacterized in nature due to analytical challenges. Electrospray ionization (ESI)-Orbitrap MS circumvents these challenges and delivers methyl-specific H-isotope compositions of acetate with nanomole sensitivity, enough to enable analyses of environmental samples. This approach quantifies the methyl-specific δ2H and molecular-average δ13C of acetate simultaneously while achieving <3 and <0.5‰ uncertainty, respectively. Using optimized ionization and Orbitrap parameters, this level of precision is obtained within 15 min using only 15 nmol of acetate. As a demonstration of our analytical approach, we cultured three acetogenic bacteria and found a large 2H-fractionation between acetate and water (>310‰ depletion) associated with the Wood-Ljungdahl pathway, while fermentation expressed a muted (∼80‰) fractionation. With its high precision and sensitivity, Orbitrap MS is a promising tool for investigating these signals in nature after offline purification. Furthermore, the ESI-Orbitrap method presented here could be applied to other molecules amenable to ESI, including central metabolites and sugars, greatly expanding the molecular targets used in hydrogen isotope biogeochemistry.


Asunto(s)
Isótopos , Espectrometría de Masa por Ionización de Electrospray , Acetatos , Espectrometría de Masa por Ionización de Electrospray/métodos
17.
ISME J ; 16(4): 915-926, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34689183

RESUMEN

Microbial metabolisms and interactions that facilitate subsurface conversions of recalcitrant carbon to methane are poorly understood. We deployed an in situ enrichment device in a subsurface coal seam in the Powder River Basin (PRB), USA, and used BONCAT-FACS-Metagenomics to identify translationally active populations involved in methane generation from a variety of coal-derived aromatic hydrocarbons. From the active fraction, high-quality metagenome-assembled genomes (MAGs) were recovered for the acetoclastic methanogen, Methanothrix paradoxum, and a novel member of the Chlorobi with the potential to generate acetate via the Pta-Ack pathway. Members of the Bacteroides and Geobacter also encoded Pta-Ack and together, all four populations had the putative ability to degrade ethylbenzene, phenylphosphate, phenylethanol, toluene, xylene, and phenol. Metabolic reconstructions, gene analyses, and environmental parameters also indicated that redox fluctuations likely promote facultative energy metabolisms in the coal seam. The active "Chlorobi PRB" MAG encoded enzymes for fermentation, nitrate reduction, and multiple oxygenases with varying binding affinities for oxygen. "M. paradoxum PRB" encoded an extradiol dioxygenase for aerobic phenylacetate degradation, which was also present in previously published Methanothrix genomes. These observations outline underlying processes for bio-methane from subbituminous coal by translationally active populations and demonstrate activity-based metagenomics as a powerful strategy in next generation physiology to understand ecologically relevant microbial populations.


Asunto(s)
Metagenómica , Metano , Carbón Mineral , Metagenoma , Metano/metabolismo , Methanosarcinaceae/metabolismo
18.
EJNMMI Res ; 11(1): 86, 2021 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-34487268

RESUMEN

BACKGROUND: 99mTc-labelled bisphosphonates are used for imaging assessment of patients with transthyretin cardiac amyloidosis (ATTR). Present study evaluates whether quantitative SPECT/CT measurement of absolute myocardial 99mTc-labelled 3,3-diphosphono-1,2-propanodicarboxylic acid (Tc-DPD) uptake can diagnose patients with suspected ATTR. METHODS: Twenty-eight patients (25 male, age 80.03 ± 6.99 years) with suspected ATTR referred for Tc-DPD imaging had planar and SPECT/CT imaging of the chest. Three operators independently obtained Tc-DPD myocardial SUVmax and SUVmean above threshold (SMaT) (20, 40 and 60% of SUVmax), using a semi-automated threshold segmentation method. Results were compared to visual grading (0-3) of cardiac uptake. RESULTS: Twenty-two patients (78%) had cardiac uptake (2 grade 1, 15 grade 2, 5 grade 3). SUVmax and SMaT segmentation thresholds enabled separating grades 2/3 from 0/1 with excellent inter- and intra-reader correlation. Cut-off values 6.0, 2.5, 3 and 4 for SUVmax, SMaT20,40,60, respectively, separated between grades 2/3 and 0 /1 with PPV and NPV of 100%. SMaT20,40,60(cardiac)/SUVmean (liver) and SMaT20,40,60(cardiac)/SUVmean(liver/lung) separated grades 2 and 3. CONCLUSION: Quantitative SPECT/CT parameters of cardiac Tc-DPD uptake are robust, enabling separation of patients with grades 2 and 3 cardiac uptake from grades 0 and 1. Larger patient cohorts will determine the incremental value of SPECT/CT quantification for ATTR management.

19.
Development ; 148(7)2021 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-33741714

RESUMEN

During craniofacial development, different populations of cartilage- and bone-forming cells develop in precise locations in the head. Most of these cells are derived from pluripotent cranial neural crest cells and differentiate with distinct developmental timing and cellular morphologies. The mechanisms that divide neural crest cells into discrete populations are not fully understood. Here, we use single-cell RNA sequencing to transcriptomically define different populations of cranial neural crest cells. We discovered that the gene family encoding the Alx transcription factors is enriched in the frontonasal population of neural crest cells. Genetic mutant analyses indicate that alx3 functions to regulate the distinct differentiation timing and cellular morphologies among frontonasal neural crest cell subpopulations. This study furthers our understanding of how genes controlling developmental timing shape craniofacial skeletal elements.


Asunto(s)
Diferenciación Celular/genética , Proteínas de Homeodominio/genética , Proteínas de Homeodominio/metabolismo , Cresta Neural/metabolismo , Proteínas de Pez Cebra/genética , Proteínas de Pez Cebra/metabolismo , Pez Cebra/genética , Pez Cebra/metabolismo , Animales , Cartílago/metabolismo , Diferenciación Celular/fisiología , Regulación del Desarrollo de la Expresión Génica , Cabeza , Ratones Transgénicos , Morfogénesis , Cresta Neural/citología , Organogénesis , Cráneo/metabolismo , Factores de Transcripción/genética , Transcriptoma , Pez Cebra/embriología
20.
Mol Genet Metab ; 132(4): 234-243, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33642210

RESUMEN

BACKGROUND: Recent years have witnessed a considerable increase in clinical trials of new investigational agents for Fabry disease (FD). Several trials investigating different agents are currently in progress; however, lack of standardisation results in challenges to interpretation and comparison. To facilitate the standardisation of investigational programs, we have developed a common framework for future clinical trials in FD. METHODS AND FINDINGS: A broad consensus regarding clinical outcomes and ways to measure them was obtained via the Delphi methodology. 35 FD clinical experts from 4 continents, representing 3389 FD patients, participated in 3 rounds of Delphi procedure. The aim was to reach a consensus regarding clinical trial design, best treatment comparator, clinical outcomes, measurement of those clinical outcomes and inclusion and exclusion criteria. Consensus results of this initiative included: the selection of the adaptative clinical trial as the ideal study design and agalsidase beta as ideal comparator treatment due to its longstanding use in FD. Renal and cardiac outcomes, such as glomerular filtration rate, proteinuria and left ventricular mass index, were prioritised, whereas neurological outcomes including cerebrovascular and white matter lesions were dismissed as a primary or secondary outcome measure. Besides, there was a consensus regarding the importance of patient-related outcomes such as general quality of life, pain, and gastrointestinal symptoms. Also, unity about lysoGb3 and Gb3 tissue deposits as useful surrogate markers of the disease was obtained. The group recognised that cardiac T1 mapping still has potential but requires further development before its widespread introduction in clinical trials. Finally, patients with end-stage renal disease or renal transplant should be excluded unless a particular group for them is created inside the clinical trial. CONCLUSION: This consensus will help to shape the future of clinical trials in FD. We note that the FDA has, coincidentally, recently published draft guidelines on clinical trials in FD and welcome this contribution.


Asunto(s)
Ensayos Clínicos como Asunto , Terapia de Reemplazo Enzimático , Enfermedad de Fabry/tratamiento farmacológico , Riñón/metabolismo , Adulto , Consenso , Técnica Delphi , Enfermedad de Fabry/genética , Enfermedad de Fabry/metabolismo , Enfermedad de Fabry/patología , Femenino , Globósidos/uso terapéutico , Glucolípidos/uso terapéutico , Humanos , Isoenzimas/genética , Riñón/efectos de los fármacos , Riñón/patología , Masculino , Persona de Mediana Edad , Calidad de Vida , Esfingolípidos/uso terapéutico , Resultado del Tratamiento , Trihexosilceramidas/uso terapéutico , alfa-Galactosidasa/genética
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