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1.
J Allergy Clin Immunol ; 152(4): 876-886, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37315813

RESUMEN

BACKGROUND: Patients with type-2 (T2) cytokine-low severe asthma often have persistent symptoms despite suppression of T2 inflammation with corticosteroids. OBJECTIVES: We sought to analyze whole blood transcriptome from 738 samples in T2-biomarker-high/-low patients with severe asthma to relate transcriptomic signatures to T2 biomarkers and asthma symptom scores. METHODS: Bulk RNA-seq data were generated for blood samples (baseline, week 24, week 48) from 301 participants recruited to a randomized clinical trial of corticosteroid optimization in severe asthma. Unsupervised clustering, differential gene expression analysis, and pathway analysis were performed. Patients were grouped by T2-biomarker status and symptoms. Associations between clinical characteristics and differentially expressed genes (DEGs) associated with biomarker and symptom levels were investigated. RESULTS: Unsupervised clustering identified 2 clusters; cluster 2 patients were blood eosinophil-low/symptom-high and more likely to be receiving oral corticosteroids (OCSs). Differential gene expression analysis of these clusters, with and without stratification for OCSs, identified 2960 and 4162 DEGs, respectively. Six hundred twenty-seven of 2960 genes remained after adjusting for OCSs by subtracting OCS signature genes. Pathway analysis identified dolichyl-diphosphooligosaccharide biosynthesis and assembly of RNA polymerase I complex as significantly enriched pathways. No stable DEGs were associated with high symptoms in T2-biomarker-low patients, but numerous associated with elevated T2 biomarkers, including 15 that were upregulated at all time points irrespective of symptom level. CONCLUSIONS: OCSs have a considerable effect on whole blood transcriptome. Differential gene expression analysis demonstrates a clear T2-biomarker transcriptomic signature, but no signature was found in association with T2-biomarker-low patients, including those with a high symptom burden.


Asunto(s)
Asma , Transcriptoma , Humanos , Asma/tratamiento farmacológico , Asma/genética , Asma/diagnóstico , Perfilación de la Expresión Génica , Biomarcadores , Corticoesteroides/uso terapéutico
2.
bioRxiv ; 2023 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-37163117

RESUMEN

The abnormal assembly of tau protein in neurons is the pathological hallmark of multiple neurodegenerative diseases, including Alzheimer's disease (AD). In addition, assembled tau associates with extracellular vesicles (EVs) in the central nervous system of patients with AD, which is linked to its clearance and prion-like propagation between neurons. However, the identities of the assembled tau species and the EVs, as well as how they associate, are not known. Here, we combined quantitative mass spectrometry, cryo-electron tomography and single-particle cryo-electron microscopy to study brain EVs from AD patients. We found filaments of truncated tau enclosed within EVs enriched in endo-lysosomal proteins. We observed multiple filament interactions, including with molecules that tethered filaments to the EV limiting membrane, suggesting selective packaging. Our findings will guide studies into the molecular mechanisms of EV-mediated secretion of assembled tau and inform the targeting of EV-associated tau as potential therapeutic and biomarker strategies for AD.

3.
Anaesthesia ; 78(6): 712-721, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37010959

RESUMEN

Ventilator-associated pneumonia commonly occurs in critically ill patients. Clinical suspicion results in overuse of antibiotics, which in turn promotes antimicrobial resistance. Detection of volatile organic compounds in the exhaled breath of critically ill patients might allow earlier detection of pneumonia and avoid unnecessary antibiotic prescription. We report a proof of concept study for non-invasive diagnosis of ventilator-associated pneumonia in intensive care (the BRAVo study). Mechanically ventilated critically ill patients commenced on antibiotics for clinical suspicion of ventilator-associated pneumonia were recruited within the first 24 h of treatment. Paired exhaled breath and respiratory tract samples were collected. Exhaled breath was captured on sorbent tubes and then analysed using thermal desorption gas chromatography-mass spectrometry to detect volatile organic compounds. Microbiological culture of a pathogenic bacteria in respiratory tract samples provided confirmation of ventilator-associated pneumonia. Univariable and multivariable analyses of volatile organic compounds were performed to identify potential biomarkers for a 'rule-out' test. Ninety-six participants were enrolled in the trial, with exhaled breath available from 92. Of all compounds tested, the four highest performing candidate biomarkers were benzene, cyclohexanone, pentanol and undecanal with area under the receiver operating characteristic curve ranging from 0.67 to 0.77 and negative predictive values from 85% to 88%. Identified volatile organic compounds in the exhaled breath of mechanically ventilated critically ill patients show promise as a useful non-invasive 'rule-out' test for ventilator-associated pneumonia.


Asunto(s)
Neumonía Asociada al Ventilador , Compuestos Orgánicos Volátiles , Humanos , Biomarcadores , Pruebas Respiratorias/métodos , Enfermedad Crítica , Neumonía Asociada al Ventilador/diagnóstico , Neumonía Asociada al Ventilador/microbiología , Sistema Respiratorio/química , Compuestos Orgánicos Volátiles/análisis
4.
Metabolomics ; 19(4): 21, 2023 03 24.
Artículo en Inglés | MEDLINE | ID: mdl-36964290

RESUMEN

INTRODUCTION: Sebum-based metabolomics (a subset of "sebomics") is a developing field that involves the sampling, identification, and quantification of metabolites found in human sebum. Sebum is a lipid-rich oily substance secreted by the sebaceous glands onto the skin surface for skin homeostasis, lubrication, thermoregulation, and environmental protection. Interest in sebomics has grown over the last decade due to its potential for rapid analysis following non-invasive sampling for a range of clinical and environmental applications. OBJECTIVES: To provide an overview of various sebum sampling techniques with their associated challenges. To evaluate applications of sebum for clinical research, drug monitoring, and human biomonitoring. To provide a commentary of the opportunities of using sebum as a diagnostic biofluid in the future. METHODS: Bibliometric analyses of selected keywords regarding skin surface analysis using the Scopus search engine from 1960 to 2022 was performed on 12th January 2023. The published literature was compartmentalised based on what the work contributed to in the following areas: the understanding about sebum, its composition, the analytical technologies used, or the purpose of use of sebum. The findings were summarised in this review. RESULTS: Historically, about 15 methods of sampling have been used for sebum collection. The sample preparation approaches vary depending on the analytes of interest and are summarised. The use of sebum is not limited to just skin diseases or drug monitoring but also demonstrated for other systemic disease. Most of the work carried out for untargeted analysis of metabolites associated with sebum has been in the recent two decades. CONCLUSION: Sebum has a huge potential beyond skin research and understanding how one's physiological state affects or reflects on the skin metabolome via the sebaceous glands itself or by interactions with sebaceous secretion, will open doors for simpler biomonitoring. Sebum acts as a sink to environmental metabolites and has applications awaiting to be explored, such as biosecurity, cross-border migration, localised exposure to harmful substances, and high-throughput population screening. These applications will be possible with rapid advances in volatile headspace and lipidomics method development as well as the ability of the metabolomics community to annotate unknown species better. A key issue with skin surface analysis that remains unsolved is attributing the source of the metabolites found on the skin surface before meaningful biological interpretation.


Asunto(s)
Metabolómica , Sebo , Humanos , Glándulas Sebáceas/metabolismo
5.
Interface Focus ; 13(2): 20220069, 2023 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-36793505

RESUMEN

Deterministic and stochastic processes are believed to play a combined role in microbial community assembly, though little is known about the factors determining their relative importance. We investigated the effect of biofilm thickness on community assembly in nitrifying moving bed biofilm reactors using biofilm carriers where maximum biofilm thickness is controlled. We examined the contribution of stochastic and deterministic processes to biofilm assembly in a steady state system using neutral community modelling and community diversity analysis with a null-modelling approach. Our results indicate that the formation of biofilms results in habitat filtration, causing selection for phylogenetically closely related community members, resulting in a substantial enrichment of Nitrospira spp. in the biofilm communities. Stochastic assembly processes were more prevalent in biofilms of 200 µm and thicker, while stronger selection in thinner (50 µm) biofilms could be driven by hydrodynamic and shear forces at the biofilm surface. Thicker biofilms exhibited greater phylogenetic beta-diversity, which may be driven by a variable selection regime caused by variation in environmental conditions between replicate carrier communities, or by drift combined with low migration rates resulting in stochastic historical contingency during community establishment. Our results indicate that assembly processes vary with biofilm thickness, contributing to our understanding of biofilm ecology and potentially paving the way towards strategies for microbial community management in biofilm systems.

6.
J Dent Res ; 101(5): 534-541, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35045743

RESUMEN

Hepatitis C virus (HCV) infection is the most common blood-borne chronic infection in the United States. Chronic lymphocytic sialadenitis and sicca syndrome have been reported in chronic HCV infection. Up to 55% of these patients may have xerostomia; the mechanisms of the xerostomia and salivary gland (SG) hypofunction remain controversial. The objectives of this project are to establish if xerostomia associates with SG and HCV infection and to characterize the structural changes in SG and saliva composition. Eighteen HCV-infected patients with xerostomia were evaluated for SG dysfunction; 6 of these patients (patients 1-6) were further evaluated for SG histopathological changes and changes in saliva composition. The techniques used include clinical and laboratory assessment, SG ultrasonography, histological evaluation, sialochemical and proteomics analysis, and RNA in situ hybridization. All the HCV patients had low saliva flow, chronic sialadenitis, and SG fibrosis and lacked Sjögren syndrome (SS) characteristic autoantibodies. Further evaluation of a subgroup of 6 HCV patients (patients 1-6) demonstrated diffuse lymphocytic infiltrates that are predominantly CD8+ T cells with a significant increase in the number of inflammatory cells. Alcian Blue/periodic acid-Schiff staining showed significant changes in the ratio and intensity of the acinar secretory units of the HCV patients' minor SG. The submandibular glands showed significant ultrasonographic abnormalities in the parenchyma relative to the parotid glands. Significant changes were also observed in the concentration of sodium and mucin 5b. Although no significant correlation was observed between the lymphocytic infiltrates and the years of HCV chronic infection, a positive correlation was observed between HCV RNA-positive epithelial cells and the years of HCV infection. Consistent with the low saliva flow and xerostomia, patients showed changes in several markers of SG acinar and ductal function. Changes in the composition of the saliva suggest that HCV infection can cause xerostomia by mechanisms distinct from SS.


Asunto(s)
Hepatitis C , Sialadenitis , Síndrome de Sjögren , Xerostomía , Linfocitos T CD8-positivos/patología , Hepacivirus , Hepatitis C/complicaciones , Humanos , Inflamación , ARN , Saliva , Glándulas Salivales/patología , Síndrome de Sjögren/complicaciones , Xerostomía/etiología
7.
J Breath Res ; 15(2)2021 01 22.
Artículo en Inglés | MEDLINE | ID: mdl-33302258

RESUMEN

Exhaled breath contains hundreds of volatile organic compounds (VOCs) which offer the potential for diagnosing and monitoring a wide range of diseases. As the breath research field has grown, sampling and analytical practices have become highly varied between groups. Standardisation would allow meta-analyses of data from multiple studies and greater confidence in published results. Washout of VOCs from ingestion into the blood and subsequently breath could provide data for an initial assessment of inter-group performance. The Peppermint Initiative has been formed to address this task of standardisation. In the current study we aimed to generate initial benchmark values for thermal desorption-gas chromatography-mass spectrometry (TD-GC-MS) analysis of breath samples containing peppermint-derived VOCs using data from three independent European research groups. Initially, headspace analysis of peppermint oil capsules was performed to determine compounds of interest. Ten healthy participants were recruited by each three groups across Europe. The standard Peppermint protocol was followed. In brief, each participant provided a baseline breath sample prior to taking a peppermint capsule, with further samples collected at 60, 90, 165, 285 and 360 min following ingestion. Sampling and analytical protocols were different for each group, in line with their usual practice. Samples were analysed by TD-GC-MS and benchmarking values determined for the time taken for detected peppermint VOCs to return to baseline values. Sixteen compounds were identified in the capsule headspace, and all were confirmed in breath following ingestion of the peppermint capsules. Additionally, 2,3-dehydro-1,8-cineole was uniquely found in the breath samples, with a washout profile that suggested it was a product of metabolism of peppermint compounds. Five compounds (α-pinene, ß-pinene, eucalyptol, menthol and menthone) were quantified by all three groups. Differences were observed between the groups, particularly for the recovery of menthone and menthol. The average time taken for VOCs to return to baseline was selected as the benchmark and were 377, 423, 533, 418 and 336 min for α-pinene, ß-pinene, eucalyptol, menthone and menthol respectively. We have presented an initial set of easy-to-measure benchmarking values for assessing the performance of TD-GC-MS systems for the analysis of VOCs in breath. These values will be updated when more groups provide additional data.


Asunto(s)
Mentha piperita , Compuestos Orgánicos Volátiles , Benchmarking , Pruebas Respiratorias/métodos , Espiración , Cromatografía de Gases y Espectrometría de Masas/métodos , Humanos , Mentha piperita/química , Compuestos Orgánicos Volátiles/análisis
8.
Mar Pollut Bull ; 159: 111481, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32768672

RESUMEN

The region around the Gulf is moving toward a nuclear energy option with the first nuclear power plant now operational in Bushehr, Iran. Others are soon to be commissioned in Abu Dhabi and in Saudi Arabia. For this reason, radiological safety is becoming a prime concern in the region. This review compiles published data on radionuclide concentrations in seawater, sediment, and biota that have been analyzed in the Gulf countries, along with spatial distribution patterns to enable a synoptic view of the available datasets. The seawater concentrations of 3H, 210Po, 210Pb, 137Cs, and 90Sr varied between 130 and 146, 0.48-0.68, 0.75-0.89, 1.25-1.38, 0.57-0.78 mBq L-1, respectively. The 226Ra concentration in seawater varied between 0.26 and 3.82 Bq L-1. Extremely high 40K concentrations between 132 and 149 Bq L-1 have been reported from the Iranian coast compared to 8.9-9.3 Bq L-1 from the western side of the Gulf. Concentrations of 40K, total 210Pb, 137Cs, 90Sr, 226Ra, 228Ra, 238U, 235U, 234U, 239+240Pu, and 238Pu were determined in sediment and ranged between 353 and 445, 23.6-44.3, 1.0-3.1, 4.8-5.29, 17.3-20.5, 15-16.4, 28.7-31.4, 1.26-1.30, 29.7-30.0, 0.045-0.21 and 0.028-0.03 Bq kg-1 dry weight, respectively. Significantly higher 137Cs values have been reported from the Iranian coast compared to the western coast of the Gulf. Whole fish concentrations of 40K, 226Ra, 224Ra, 228Ra, 137Cs, 210Po and 90Sr ranged between 230 and 447, 0.7-7.3, <0.5-6.6, <0.5-15.80, <0.17, 0.88-4.26 and 1.86-5.34 Bq kg-1 dry weight, respectively. 210Po was found to be highly concentrated in several marine organisms with the highest 210Po concentration found in the clam Marcia marmorata (193.5-215.6 Bq kg-1 dry weight). The review highlights the overall paucity of data and inconsistencies in the measurement of radionuclides throughout the Gulf region. Further, since the region is moving toward nuclear energy to meet its increasing energy demand, and coupled with the environmental effects from offshore oil exploration and the heavy impact of climate change, there is a pressing need to undertake a comprehensive marine radioactivity monitoring and assessment effort by conducting a joint cruise in the Gulf with participation of all the adjoining countries. Several recommendations on sampling marine matrixes in the Gulf are given with the aim of improving comparability of radionuclide data from the various studies undertaken in the Gulf region.


Asunto(s)
Monitoreo de Radiación , Radiactividad , Contaminantes Radiactivos del Agua/análisis , Animales , Irán , Arabia Saudita , Agua de Mar , Emiratos Árabes Unidos
9.
mBio ; 10(6)2019 11 05.
Artículo en Inglés | MEDLINE | ID: mdl-31690672

RESUMEN

Nitrification, the oxidative process converting ammonia to nitrite and nitrate, is driven by microbes and plays a central role in the global nitrogen cycle. Our earlier investigations based on 16S rRNA and amoA amplicon analysis, amoA quantitative PCR and metagenomics of groundwater-fed biofilters indicated a consistently high abundance of comammox Nitrospira Here, we hypothesized that these nonclassical nitrifiers drive ammonia-N oxidation. Hence, we used DNA and RNA stable isotope probing (SIP) coupled with 16S rRNA amplicon sequencing to identify the active members in the biofilter community when subjected to a continuous supply of NH4+ or NO2- in the presence of 13C-HCO3- (labeled) or 12C-HCO3- (unlabeled). Allylthiourea (ATU) and sodium chlorate were added to inhibit autotrophic ammonia- and nitrite-oxidizing bacteria, respectively. Our results confirmed that lineage II Nitrospira dominated ammonia oxidation in the biofilter community. A total of 78 (8 by RNA-SIP and 70 by DNA-SIP) and 96 (25 by RNA-SIP and 71 by DNA-SIP) Nitrospira phylotypes (at 99% 16S rRNA sequence similarity) were identified as complete ammonia- and nitrite-oxidizing, respectively. We also detected significant HCO3- uptake by Acidobacteria subgroup10, Pedomicrobium, Rhizobacter, and Acidovorax under conditions that favored ammonia oxidation. Canonical Nitrospira alone drove nitrite oxidation in the biofilter community, and activity of archaeal ammonia-oxidizing taxa was not detected in the SIP fractions. This study provides the first in situ evidence of ammonia oxidation by comammox Nitrospira in an ecologically relevant complex microbiome.IMPORTANCE With this study we provide the first in situ evidence of ecologically relevant ammonia oxidation by comammox Nitrospira in a complex microbiome and document an unexpectedly high H13CO3- uptake and growth of proteobacterial and acidobacterial taxa under ammonia selectivity. This finding raises the question of whether comammox Nitrospira is an equally important ammonia oxidizer in other environments.


Asunto(s)
Bacterias/genética , ADN/genética , Agua Subterránea/microbiología , Nitrificación/genética , ARN Ribosómico 16S/genética , Amoníaco/metabolismo , Archaea/genética , Procesos Autotróficos/genética , Isótopos , Nitratos/metabolismo , Nitritos/metabolismo , Ciclo del Nitrógeno/genética , Oxidación-Reducción
10.
Environ Sci Technol ; 53(21): 12433-12441, 2019 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-31593453

RESUMEN

Copper is a cofactor of the ammonia monooxygenase, an essential enzyme for the activity of ammonia oxidizing prokaryotes (AOP). Copper dosing at less than 1 µg/L stimulated ammonium removal in the poorly nitrifying biological filters of three full-scale drinking water treatment plants. Upon copper dosing, the ammonium concentration in the effluent decreased from up to 0.18 to less than 0.01 mg NH4+-N/L. To investigate how copper dosing affected the filter microbial community, we applied amplicon sequencing and qPCR targeting key nitrifying groups, including complete ammonia oxidizing (comammox) Nitrospira. Copper dosing increased the abundance of different nitrifiers. Multiple Nitrosomonas variants (betaproteobacterial ammonia oxidizers), which initially collectively represented 1% or less of the total community, increased almost 10-fold. Comammox Nitrospira were abundant and increased too, but their relative abundance within the AOP decreased because of Nitrosomonas proliferation. No other consistent change in the filter communities was detected, as well as no adverse effect of copper on the filters functionality. Our results show that copper dosing in three independent treatment plants was associated with consistent growth of AOP and that efficient nitrification was achieved through the joint contribution of comammox Nitrospira and an increasing fraction of betaproteobacterial ammonia oxidizers.


Asunto(s)
Agua Potable , Nitrificación , Amoníaco , Proliferación Celular , Cobre , Nitritos , Nitrosomonas , Oxidación-Reducción
11.
Nat Nanotechnol ; 14(6): 623, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31101862

RESUMEN

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

12.
Nat Nanotechnol ; 14(5): 401-402, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-31065069
13.
Respir Med ; 150: 66-73, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30961953

RESUMEN

Gastro-oesophageal reflux disease (GORD) has long been associated with poor asthma control without an established cause-effect relationship. 610 asthmatics (421 severe/88 mild-moderate) and 101 healthy controls were assessed clinically and a subset of 154 severe asthmatics underwent proteomic analysis of induced sputum using untargeted mass spectrometry, LC-IMS-MSE. Univariate and multiple logistic regression analyses (MLR) were conducted to identify proteins associated with GORD in this cohort. When compared to mild/moderate asthmatics and healthy individuals, respectively, GORD was three- and ten-fold more prevalent in severe asthmatics and was associated with increased asthma symptoms and oral corticosteroid use, poorer quality of life, depression/anxiety, obesity and symptoms of sino-nasal disease. Comparison of sputum proteomes in severe asthmatics with and without active GORD showed five differentially abundant proteins with described roles in anti-microbial defences, systemic inflammation and epithelial integrity. Three of these were associated with active GORD by multiple linear regression analysis: Ig lambda variable 1-47 (p = 0·017) and plasma protease C1 inhibitor (p = 0·043), both in lower concentrations, and lipocalin-1 (p = 0·034) in higher concentrations in active GORD. This study provides evidence which suggests that reflux can cause subtle perturbation of proteins detectable in the airways lining fluid and that severe asthmatics with GORD may represent a distinct phenotype of asthma.


Asunto(s)
Asma/complicaciones , Asma/metabolismo , Reflujo Gastroesofágico/complicaciones , Proteómica/métodos , Esputo/metabolismo , Adulto , Asma/epidemiología , Asma/psicología , Endopeptidasas/metabolismo , Unión Europea/organización & administración , Femenino , Reflujo Gastroesofágico/diagnóstico , Reflujo Gastroesofágico/epidemiología , Humanos , Cadenas lambda de Inmunoglobulina/metabolismo , Lipocalina 1/metabolismo , Masculino , Persona de Mediana Edad , Prevalencia , Estudios Prospectivos , Inhibidores de Proteasas/metabolismo , Calidad de Vida , Índice de Severidad de la Enfermedad
14.
ISME J ; 12(7): 1779-1793, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29515170

RESUMEN

The description of comammox Nitrospira spp., performing complete ammonia-to-nitrate oxidation, and their co-occurrence with canonical ß-proteobacterial ammonia oxidizing bacteria (ß-AOB) in the environment, calls into question the metabolic potential of comammox Nitrospira and the evolutionary history of their ammonia oxidation pathway. We report four new comammox Nitrospira genomes, constituting two novel species, and the first comparative genomic analysis on comammox Nitrospira. Unlike canonical Nitrospira, comammox Nitrospira genomes lack genes for assimilatory nitrite reduction, suggesting that they have lost the potential to use external nitrite nitrogen sources. By contrast, compared to canonical Nitrospira, comammox Nitrospira harbor a higher diversity of urea transporters and copper homeostasis genes and lack cyanate hydratase genes. Additionally, the two comammox clades differ in their ammonium uptake systems. Contrary to ß-AOB, comammox Nitrospira genomes have single copies of the two central ammonia oxidation pathway operons. Similar to ammonia oxidizing archaea and some oligotrophic AOB strains, they lack genes involved in nitric oxide reduction. Furthermore, comammox Nitrospira genomes encode genes that might allow efficient growth at low oxygen concentrations. Regarding the evolutionary history of comammox Nitrospira, our analyses indicate that several genes belonging to the ammonia oxidation pathway could have been laterally transferred from ß-AOB to comammox Nitrospira. We postulate that the absence of comammox genes in other sublineage II Nitrospira genomes is the result of subsequent loss.


Asunto(s)
Amoníaco/metabolismo , Betaproteobacteria/genética , Betaproteobacteria/metabolismo , Evolución Molecular , Archaea/clasificación , Archaea/genética , Archaea/aislamiento & purificación , Archaea/metabolismo , Betaproteobacteria/clasificación , Betaproteobacteria/aislamiento & purificación , Genómica , Nitratos/metabolismo , Nitrificación , Nitritos/metabolismo , Oxidación-Reducción
17.
Meat Sci ; 134: 124-127, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28783608

RESUMEN

The current study examined the effect of vascular rinsing lamb carcases (Rinse & Chill®) with a commercially available isotonic substrate solution (98.5% water; balance: glucose, polyphosphates, and maltose) at 14°C. Thirty, lamb carcases were randomly allocated to receive either the solution (n=15) 25 min post slaughter on a slaughter line or no solution (n=15). There was no apparent effect on the rate of pH decline due to infusion or muscle shortening of the M. longissimus thoracis et lumborum (LL), but there was a more than 50% reduction in toughness (lower shear force) of the LL due to infusion. Infusion resulted in lighter (L*), yellower (b*) LL and this effect was maintained during simulated colour display. There was no impact on redness (a*) of the LL and in fact a critical consumer threshold for redness was not breached on average for infused or non-infused LL. There was no evidence of elevated levels of metmyoglobin formation or lipid oxidation.


Asunto(s)
Glucosa/administración & dosificación , Maltosa/administración & dosificación , Polifosfatos/administración & dosificación , Carne Roja/análisis , Mataderos , Animales , Color , Manipulación de Alimentos/métodos , Glucosa/farmacología , Concentración de Iones de Hidrógeno , Infusiones Intravenosas/veterinaria , Lípidos , Maltosa/farmacología , Metamioglobina/análisis , Músculo Esquelético/química , Oxidación-Reducción , Polifosfatos/farmacología , Carne Roja/normas , Oveja Doméstica , Soluciones
18.
Genes Brain Behav ; 16(5): 522-536, 2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-28239983

RESUMEN

Parkinson's disease is a debilitating neurodegenerative condition for which there is no cure. Converging evidence implicates gangliosides in the pathogenesis of several neurodegenerative diseases, suggesting a potential new class of therapeutic targets. We have shown that interventions that simultaneously increase the neuroprotective GM1 ganglioside and decrease the pro-apoptotic GD3 ganglioside - such as inhibition of GD3 synthase (GD3S) or administration of sialidase - are neuroprotective in vitro and in a number of preclinical models. In this study, we investigated the effects of GD3S deletion on parkinsonism induced by 1-methyl-4phenyl-1,2,3,6-tetrahydropyridine (MPTP). MPTP was administered to GD3S-/- mice or controls using a subchronic regimen consisting of three series of low-dose injections (11 mg/kg/day × 5 days each, 3 weeks apart), and motor function was assessed after each. The typical battery of tests used to assess parkinsonism failed to detect deficits in MPTP-treated mice. More sensitive measures - such as the force-plate actimeter and treadmill gait parameters - detected subtle effects of MPTP, some of which were absent in mice lacking GD3S. In wild-type mice, MPTP destroyed 53% of the tyrosine-hydroxylase (TH)-positive neurons in the substantia nigra pars compacta (SNc) and reduced striatal dopamine 60.7%. In contrast, lesion size was only 22.5% in GD3S-/- mice and striatal dopamine was reduced by 37.2%. Stereological counts of Nissl-positive SNc neurons that did not express TH suggest that neuroprotection was complete but TH expression was suppressed in some cells. These results show that inhibition of GD3S has neuroprotective properties in the MPTP model and may warrant further investigation as a therapeutic target.


Asunto(s)
Eliminación de Gen , Intoxicación por MPTP/genética , Sialiltransferasas/genética , Animales , Dopamina/metabolismo , Neuronas Dopaminérgicas/metabolismo , Neuronas Dopaminérgicas/patología , Locomoción , Ratones , Ratones Endogámicos C57BL , Sustancia Negra/metabolismo , Sustancia Negra/patología , Sustancia Negra/fisiopatología
19.
J Environ Radioact ; 174: 23-29, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27670204

RESUMEN

The tendency of 210Po to concentrate in body tissue poses a serious concern of radiological safety. This study compiles available information and presents recent 210Po data for the marine food web in the northern Gulf waters. Since 210Po is concentrated in marine biota, a large number of samples of various marine organisms covering several trophic levels, from microalgae to sharks, were analyzed. 210Po was found to be highly concentrated in several marine species with the highest 210Po concentrations found in yellowfin tuna, i.e. 37.3-44.9, 451-548, and 1511-1693 Bq kg-1 wwt in muscle, digestive system and liver, respectively. In most dissected fish samples, 210Po showed increasing concentrations in the following order: edible tissue, gills, digestive system, liver and fecal matter. Fish feces had 210Po concentrations several orders of magnitude higher than that in seawater, fish muscle, and the fishes' ingested food. The high 210Po concentration in fish fecal matter suggests that the bulk of 210Po content in fish is eventually excreted back into the environment as fecal pellets. In most fish high concentrations were noted in liver, with the highest 210Po concentration recorded in yellowfin tuna liver. Moreover, 210Po concentration in the soft tissue of tunicate and bryozoan samples were 872-1012 and 402-527 Bq kg-1 wwt, respectively, far higher than that in fish muscle (0.04-44.9 Bq kg-1 wwt). It was observed that the maximum 210Po concentration in edible fish tissue among the fish in trophic level 2 was an order of magnitude lower than those in trophic level 3 and two orders of magnitude lower compared to fish in trophic level 4. The highest concentrations in the muscle tissue were observed in the following order: tunicate > bryozoan > mollusc > crustacean > algae > fish. Among all the biota analyzed, the highest overall concentration of 210Po was noted in yellowfin tuna (Thunnus albacores) indicating a potential biomagnification of 210Po in this particular top predator species. In general, 210Po concentrations found in the commercially important fish from Kuwaiti waters were comparable to levels that have been reported for similar fish species from several other marine areas worldwide.


Asunto(s)
Cadena Alimentaria , Polonio/metabolismo , Monitoreo de Radiación , Contaminantes Radiactivos del Agua/metabolismo , Animales , Peces , Océano Índico , Moluscos , Polonio/análisis , Agua de Mar , Tiburones , Contaminantes Radiactivos del Agua/análisis
20.
Artículo en Inglés | MEDLINE | ID: mdl-30345429

RESUMEN

In transitional age youth living with HIV or AIDS, non-adherence (<80%) to anti-retroviral medication is associated with viral resistance, disease progression, and an increased risk of death. This feasibility study investigated the Maya MedMinder electronic pillbox and cell phone texting with personalized motivational interviewing strategies to improve medication adherence in non-adherent youth. Twenty patients out of 30 identified as non-adherent by the Pediatric HIV team at the Medical University of South Carolina were approached, and 15 were recruited (Ages 12 to 20; 13.3% male, 86.7% female; 100% African-American). Following baseline MedMinder monitoring, subjects were randomized to intervention groups with reminder signals on or off. The time medications were taken was collected by the MedMinder, resulting in adherence scores. All were interviewed for readiness to change utilizing the Motivational Interviewing (MI) Stages of Change scores. Viral load and CD4 labs were scheduled every 6 weeks. Despite monetary incentives and personalized support, recruitment and adherence to the protocol was a challenge. Only 6/15 subjects completed the entire study scheduled for 6-months .Stages of change scores revealed that those that transitioned to making changes had higher CD4 percentages midway through the study. Challenges included missed appointments and labs despite efforts by text and phone to schedule convenient appointment times with participants. Device challenges included the large size of the MedMinder and faulty electronic signaling, especially from rural areas. The methodology was feasible with these patients. This small feasibility study highlights that technological tools to promote adherence and motivational enhancement strategies in teens and young adults who are non-adherent to HIV medication regimens can enhance biomarker outcomes associated with medication adherence.

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