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1.
Vet Sci ; 10(2)2023 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-36851425

RESUMO

Red blood cell (RBC) transfusion is associated with recipient inflammation and infection, which may be triggered by excessive circulating iron. Iron chelation following transfusion may reduce these risks. The aim of this study was to evaluate the effect of deferoxamine on circulating iron and inflammation biomarkers over time and in vitro growth of Escherichia coli (E. coli) following RBC transfusion in dogs with atraumatic hemorrhage. Anesthetized dogs were subject to atraumatic hemorrhage and transfusion of RBCs, then randomized to receive either deferoxamine or saline placebo of equivalent volume (n = 10 per group) in a blinded fashion. Blood was sampled before hemorrhage and then 2, 4, and 6 h later. Following hemorrhage and RBC transfusion, free iron increased in all dogs over time (both p < 0.001). Inflammation biomarkers interleukin-6 (IL6), CXC motif chemokine-8 (CXCL8), interleukin-10 (IL10), and keratinocyte-derived chemokine (KC) increased in all dogs over time (all p < 0.001). Logarithmic growth of E. coli clones within blood collected 6 h post-transfusion was not different between groups. Only total iron-binding capacity was different between groups over time, being significantly increased in the deferoxamine group at 2 and 4 h post-transfusion (both p < 0.001). In summary, while free iron and inflammation biomarkers increased post-RBC transfusion, deferoxamine administration did not impact circulating free iron, inflammation biomarkers, or in vitro growth of E. coli when compared with placebo.

2.
iScience ; 25(1): 103571, 2022 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-34984327

RESUMO

Mesothelioma is a cancer that typically originates in the pleura of the lungs. It rapidly invades the surrounding tissues, causing pain and shortness of breath. We compared cell lines injected either subcutaneously or intrapleurally and found that only the latter resulted in invasive and rapid growth. Pleural tumors displayed a transcriptional signature consistent with increased activity of nuclear receptors PPARα and PPARγ and with an increased abundance of endogenous PPAR-activating ligands. We found that chemical probe GW6471 is a potent, dual PPARα/γ antagonist with anti-invasive and anti-proliferative activity in vitro. However, administration of GW6471 at doses that provided sustained plasma exposure levels sufficient for inhibition of PPARα/γ transcriptional activity did not result in significant anti-mesothelioma activity in mice. Lastly, we demonstrate that the in vitro anti-tumor effect of GW6471 is off-target. We conclude that dual PPARα/γ antagonism alone is not a viable treatment modality for mesothelioma.

3.
PLoS One ; 16(6): e0253838, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34191849

RESUMO

Bee venom (BV) is the most valuable product harvested from honeybees ($30 - $300 USD per gram) but marginally produced in apiculture. Though widely studied and used in alternative medicine, recent efforts in BV research have focused on its therapeutic and cosmetic applications, for the treatment of degenerative and infectious diseases. The protein and peptide composition of BV is integral to its bioactivity, yet little research has investigated the ecological factors influencing the qualitative and quantitative variations in the BV composition. Bee venom from Apis mellifera ligustica (Apidae), collected over one flowering season of Corymbia calophylla (Myrtaceae; marri) was characterized to test if the protein composition and amount of BV variation between sites is influenced by i) ecological factors (temperature, relative humidity, flowering index and stage, nectar production); ii) management (nutritional supply and movement of hives); and/or iii) behavioural factors. BV samples from 25 hives across a 200 km-latitudinal range in Southwestern Australia were collected using stimulatory devices. We studied the protein composition of BV by mass spectrometry, using a bottom-up proteomics approach. Peptide identification utilised sequence homology to the A. mellifera reference genome, assembling a BV peptide profile representative of 99 proteins, including a number of previously uncharacterised BV proteins. Among ecological factors, BV weight and protein diversity varied by temperature and marri flowering stage but not by index, this latter suggesting that inter and intra-year flowering index should be further explored to better appreciate this influence. Site influenced BV protein diversity and weight difference in two sites. Bee behavioural response to the stimulator device impacted both the protein profile and weight, whereas management factors did not. Continued research using a combination of proteomics, and bio-ecological approaches is recommended to further understand causes of BV variation in order to standardise and improve the harvest practice and product quality attributes.


Assuntos
Venenos de Abelha/análise , Abelhas/química , Ecossistema , Animais , Comportamento Animal , Cromatografia Líquida , Flores/fisiologia , Proteínas de Insetos/análise , Análise de Componente Principal , Estações do Ano , Espectrometria de Massas em Tandem , Austrália Ocidental
4.
J Am Soc Mass Spectrom ; 32(7): 1829-1836, 2021 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-34047188

RESUMO

Imaging mass spectrometry has emerged as a powerful metabolite measurement approach to capture the spatial dimension of metabolite distribution in a biological sample. In matrix-assisted laser desorption ionization-mass spectrometry imaging (MALDI-MSI), deposition of the chemical-matrix onto the sample serves to simultaneously extract biomolecules to the sample surface and concurrently render the sample amenable to MALDI. However, matrix application may mobilize sample metabolites and will dictate the efficiency of matrix crystallization, together limiting the lateral resolution which may be optimally achieved by MSI. Here, we describe a matrix application technique, herein referred to as the "freeze-spot" method, conceived as a low-cost preparative approach requiring minimal amounts of chemical matrix while maintaining the spatial dimension of sample metabolites for MALDI-MSI. Matrix deposition was achieved by pipette spot application of the matrix-solubilized within a solvent solution with a freezing point above that of a chilled sample stage to which the sample section is mounted. The matrix solution freezes on contact with the sample and the solvent is removed by sublimation, leaving a fine crystalline matrix on the sample surface. Freeze-spotting is quick to perform, found particularly useful for MALDI-MSI of small sample sections, and well suited to efficient and cost-effective method development pipelines, while capable of maintaining the lateral resolution required by MSI.


Assuntos
Congelamento , Imagem Molecular/métodos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Sementes/química , Açúcares/química , Triticum/química
5.
Intensive Care Med ; 47(3): 307-315, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33566129

RESUMO

PURPOSE: In adults requiring treatment in an intensive care unit, probiotic therapy using Lactobacillus plantarum 299v may reduce nosocomial infection. The aim of this study was to determine whether early and sustained L. plantarum 299v therapy administered to adult ICU patients increased days alive and at home. METHODS: A multicentre, parallel group, placebo-controlled, randomised clinical trial was conducted. Adult patients within 48 h of intensive care admission and expected to require intensive care beyond the day after recruitment were eligible to participate. L plantarum 299v or placebo were administered immediately after enrolment and continued for 60 days. The primary outcome was days alive and out of hospital to Day 60 (DAOH60). Secondary outcomes included nosocomial infections. RESULTS: The median [interquartile range (IQR)] number of DAOH60 in the probiotic (n = 110) and placebo group (n = 108) was 49.5 (IQR 37.0-53.0) and 49.0 (IQR 43.8-53.0) respectively, between-group difference of 0.0 [95% confidence interval (CI) - 6.10 to 7.1, P = 0.55]. Nosocomial infection occurred in 8 (7.3%) and 5 (4.6%) of the probiotic and placebo group participants, respectively, odds ratio 1.62 (95% CI 0.51-5.10), P = 0.57. There were no serious, or probiotic-associated adverse events. CONCLUSION: Early and sustained untargeted administration of probiotic therapy with Lactobacillus plantarum 299v to adult patients admitted to the ICU is safe, but not associated with improved patient outcomes.


Assuntos
Microbioma Gastrointestinal , Lactobacillus plantarum , Probióticos , Adulto , Estado Terminal , Método Duplo-Cego , Humanos , Probióticos/uso terapêutico
6.
Proteomics Clin Appl ; 15(2-3): e2000039, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33580915

RESUMO

Chronic obstructive pulmonary disease (COPD) is characterised by airway inflammation and progressive airflow limitation, whereas idiopathic pulmonary fibrosis (IPF) is characterised by a restrictive pattern due to fibrosis and impaired gas exchange. We undertook metabolomic analysis of blood samples in IPF, COPD and healthy controls (HC) to determine differences in circulating molecules and identify novel pathogenic pathways. An untargeted metabolomics using an ultra-high-performance liquid chromatography-quadrupole time-of-flight mass spectrometer (UHPLC-QTOF-MS) was performed to profile plasma of patients with COPD (n = 21), and IPF (n = 24) in comparison to plasma from healthy controls (HC; n = 20). The most significant features were identified using multiple database matching. One-way ANOVA and variable importance in projection (VIP) scores were also used to highlight metabolites that influence the specific disease groups. Non-polar metabolites such as fatty acids (FA) and membrane lipids were well resolved and a total of 4805 features were identified. The most prominent metabolite composition differences in lipid mediators identified at ∼2-3 fold higher in both diseases compared to HC were palmitoleic acid, oleic acid and linoleic acid; and dihydrotestosterone was lower in both diseases. We demonstrated that COPD and IPF were characterised by systemic changes in lipid constituents such as essential FA sampled from circulating plasma.


Assuntos
Fibrose Pulmonar Idiopática
7.
BMJ Open ; 10(6): e035930, 2020 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-32565465

RESUMO

INTRODUCTION: The effect of early and sustained administration of daily probiotic therapy on patients admitted to the intensive care unit (ICU) remains uncertain. METHODS AND ANALYSIS: The Restoration Of gut microflora in Critical Illness Trial (ROCIT) study is a multicentre, randomised, placebo-controlled, parallel-group, two-sided superiority trial that will enrol 220 patients in five ICUs. Adult patients who are within 48 hours of admission to an ICU and are expected to require intensive care beyond the next calendar day will be randomised in a 1:1 ratio to receive early and sustained Lactobacillus plantarum 299v probiotic therapy in addition to usual care or placebo in addition to usual care. The primary endpoint is days alive and out of hospital to day 60. ETHICS AND DISSEMINATION: ROCIT has been approved by the South Metropolitan Health Service Human Research Ethics Committee (ref: RGS00000004) and the St John of God Health Care Human Research Ethics Committee (ref: 1183). The trial results will be submitted for publication in a peer-reviewed journal. TRIAL REGISTRATION NUMBER: Australian and New Zealand Clinical Trials Registry (ANZCTR12617000783325); Pre-results.


Assuntos
Cuidados Críticos/métodos , Estado Terminal , Estudos de Equivalência como Asunto , Microbioma Gastrointestinal , Probióticos/uso terapêutico , Austrália , Humanos , Unidades de Terapia Intensiva , Estudos Multicêntricos como Assunto , Nova Zelândia , Projetos de Pesquisa
8.
J Vis Exp ; (157)2020 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-32225158

RESUMO

Understanding the interactions between genes, the environment and management in agricultural practice could allow more accurate prediction and management of product yield and quality. Metabolomics data provides a read-out of these interactions at a given moment in time and is informative of an organism's biochemical status. Further, individual metabolites or panels of metabolites can be used as precise biomarkers for yield and quality prediction and management. The plant metabolome is predicted to contain thousands of small molecules with varied physicochemical properties that provide an opportunity for a biochemical insight into physiological traits and biomarker discovery. To exploit this, a key aim for metabolomics researchers is to capture as much of the physicochemical diversity as possible within a single analysis. Here we present a liquid chromatography-mass spectrometry-based untargeted metabolomics method for the analysis of field-grown wheat grain. The method uses the liquid chromatograph quaternary solvent manager to introduce a third mobile phase and combines a traditional reversed-phase gradient with a lipid-amenable gradient. Grain preparation, metabolite extraction, instrumental analysis and data processing workflows are described in detail. Good mass accuracy and signal reproducibility were observed, and the method yielded approximately 500 biologically relevant features per ionization mode. Further, significantly different metabolite and lipid feature signals between wheat varieties were determined.


Assuntos
Cromatografia Líquida/métodos , Espectrometria de Massas/métodos , Metabolômica/métodos , Triticum/química , Reprodutibilidade dos Testes
9.
Respirology ; 25(2): 139-148, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-30907495

RESUMO

Chronic lung diseases represent a significant global burden. Their increasing incidence and complexity render a comprehensive, multidisciplinary and personalized approach to each patient, critically important. Most recently, unique biochemical pathways and disease markers have been identified through large-scale metabolomic studies. Metabolomics is the study of metabolic pathways and the measurement of unique biomolecules in a living system. Analysing samples from different compartments such as bronchoalveolar lavage fluid (BALF) and plasma has proven useful for the characterization of a number of pathological conditions and offers promise as a clinical tool. For example, several studies using mass spectrometry (MS) have shown alterations in the sphingolipid metabolism of chronic obstructive pulmonary disease (COPD) sufferers. In this article, we present a practical review of the application of metabolomics to the study of chronic lung diseases (CLD): COPD, idiopathic pulmonary fibrosis (IPF) and asthma. The insights, which the analytical strategies employed in metabolomics, have provided to the dissection of the biochemistry of CLD and future clinical biomarkers are explored.


Assuntos
Asma/metabolismo , Fibrose Pulmonar Idiopática/metabolismo , Metabolômica , Doença Pulmonar Obstrutiva Crônica/metabolismo , Biomarcadores/metabolismo , Líquido da Lavagem Broncoalveolar , Humanos , Metabolismo dos Lipídeos , Redes e Vias Metabólicas
10.
Sci Rep ; 9(1): 19400, 2019 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-31852911

RESUMO

Hepcidins are an evolutionarily conserved class of liver-expressed peptide, from which the twenty-five amino acid hormone, hepcidin-25 (herein hepcidin), has gained significant notoriety as the master regulator of iron homeostasis in mammals. Hepcidin maintains iron homeostasis by controlling the dietary absorption of iron and the mechanisms of recycling cellular iron stores. With the physiological significance of this hormone well established, it has emerged as an informative biomarker. In a comparison of the genome, transcriptome and peptidome of Canis lupis familiaris, we reveal the size of the hepcidin peptide in the canine, previous reports of which were contradictory to the evolutionary conservation predicted by genome annotation. Here, measurement of the peptide by mass spectrometry, following isolation from greyhound blood serum, revealed an amino acid sequence and peptide mass, differing from all accounts to date, yet demonstrating perfect sequence identity to that of the greater Canidae lineage of the Carnivora. Importantly, in the greyhound, the measured hepcidin peptide showed a similar temporal pattern to total serum iron, consistent with our understanding of hepcidin regulating iron homeostasis, in agreement with human diagnostics, and providing added translational evidence of the measured peptide being the iron regulatory hormone of the Canidae.


Assuntos
Evolução Molecular , Hepcidinas/genética , Ferro/metabolismo , Sequência de Aminoácidos , Animais , Biomarcadores/metabolismo , Cães , Hepcidinas/metabolismo , Homeostase/genética , Humanos , Mamíferos
11.
Cell Microbiol ; 21(10): e13089, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31373151

RESUMO

Chytridiomycosis, caused by the fungus Batrachochytrium dendrobatidis (Bd), is a skin disease responsible for the global decline of amphibians. Frog species and populations can vary in susceptibility, but this phenomenon remains poorly understood. Here, we investigated serotonin in the skin of infected and uninfected frogs. In more susceptible frog populations, skin serotonin rose with increasing infection intensity, but decreased in later stages of the disease. The more resistant population maintained a basal level of skin serotonin. Serotonin inhibited both Bd sporangial growth and Jurkat lymphocyte proliferation in vitro. However, serotonin accumulates in skin granular glands, and this compartmentalisation may prevent inhibition of Bd growth in vivo. We suggest that skin serotonin increases in susceptible frogs due to pathogen excretion of precursor tryptophan, but that resistant frogs are able to control the levels of serotonin. Overall, the immunosuppressive effects of serotonin may contribute to the susceptibility of frogs to chytridiomycosis.


Assuntos
Anuros/microbiologia , Quitridiomicetos , Suscetibilidade a Doenças/veterinária , Micoses/veterinária , Serotonina/metabolismo , Dermatopatias/veterinária , Pele/metabolismo , Animais , Anuros/imunologia , Anuros/metabolismo , Austrália , Proliferação de Células/efeitos dos fármacos , Quitridiomicetos/efeitos dos fármacos , Suscetibilidade a Doenças/metabolismo , Suscetibilidade a Doenças/microbiologia , Cromatografia Gasosa-Espectrometria de Massas , Micoses/imunologia , Micoses/metabolismo , Serotonina/farmacologia , Pele/química , Pele/microbiologia , Dermatopatias/metabolismo , Esporângios/efeitos dos fármacos , Esporângios/crescimento & desenvolvimento , Linfócitos T/efeitos dos fármacos
13.
J Chromatogr B Analyt Technol Biomed Life Sci ; 1118-1119: 25-32, 2019 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-31005771

RESUMO

Polycystic kidney disease (PKD) encompasses a spectrum of inherited disorders that lead to end-stage renal disease (ESRD). There is no cure for PKD and current treatment options are limited to renal replacement therapy and transplantation. A better understanding of the pathobiology of PKD is needed for the development of new, less invasive treatments. The Lewis Polycystic Kidney (LPK) rat phenotype has been characterized and classified as a model of nephronophthisis (NPHP9, caused by mutation of the Nek8 gene) for which polycystic kidneys are one of the main pathologic features. The aim of this study was to use a GC-MS-based untargeted metabolomics approach to determine key biochemical changes in kidney and liver tissue of the LPK rat. Tissues from 16-week old LPK (n = 10) and Lewis age- and sex-matched control animals (n = 11) were used. Principal component analysis (PCA) distinguished signal corrected metabolite profiles from Lewis and LPK rats for kidney (PC-1 77%) and liver (PC-1 46%) tissue. There were marked differences in the metabolite profiles of the kidney tissues with 122 deconvoluted features significantly different between the LPK and Lewis strains. The metabolite profiles were less marked between strains for liver samples with 30 features significantly different. Five biochemical pathways showed three or more significantly altered metabolites: transcription/translation, arginine and proline metabolism, alpha-linolenic and linoleic acid metabolism, the citric acid cycle, and the urea cycle. The results of this study validate and complement the current literature and are consistent with the understood pathobiology of PKD.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Rim/metabolismo , Fígado/metabolismo , Metabolômica/métodos , Doenças Renais Policísticas/metabolismo , Aminoácidos/análise , Aminoácidos/metabolismo , Animais , Biomarcadores/análise , Biomarcadores/metabolismo , Feminino , Masculino , Metaboloma/fisiologia , Ratos , Reprodutibilidade dos Testes
14.
Exp Physiol ; 104(1): 81-92, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30311980

RESUMO

NEW FINDINGS: What is the central question of this study? Does 14 days of live-high, train-low simulated altitude alter an individual's metabolomic/metabolic profile? What is the main finding and its importance? This study demonstrated that ∼200 h of moderate simulated altitude exposure resulted in greater variance in measured metabolites between subject than within subject, which indicates individual variability during the adaptive phase to altitude exposure. In addition, metabolomics results indicate that altitude alters multiple metabolic pathways, and the time course of these pathways is different over 14 days of altitude exposure. These findings support previous literature and provide new information on the acute adaptation response to altitude. ABSTRACT: The purpose of this study was to determine the influence of 14 days of normobaric hypoxic simulated altitude exposure at 3000 m on the human plasma metabolomic profile. For 14 days, 10 well-trained endurance runners (six men and four women; 29 ± 7 years of age) lived at 3000 m simulated altitude, accumulating 196.4 ± 25.6 h of hypoxic exposure, and trained at ∼600 m. Resting plasma samples were collected at baseline and on days 3 and 14 of altitude exposure and stored at -80°C. Plasma samples were analysed using liquid chromatography-high-resolution mass spectrometry to construct a metabolite profile of altitude exposure. Mass spectrometry of plasma identified 36 metabolites, of which eight were statistically significant (false discovery rate probability 0.1) from baseline to either day 3 or day 14. Specifically, changes in plasma metabolites relating to amino acid metabolism (tyrosine and proline), glycolysis (adenosine) and purine metabolism (adenosine) were observed during altitude exposure. Principal component canonical variate analysis showed significant discrimination between group means (P < 0.05), with canonical variate 1 describing a non-linear recovery trajectory from baseline to day 3 and then back to baseline by day 14. Conversely, canonical variate 2 described a weaker non-recovery trajectory and increase from baseline to day 3, with a further increase from day 3 to 14. The present study demonstrates that metabolomics can be a useful tool to monitor metabolic changes associated with altitude exposure. Furthermore, it is apparent that altitude exposure alters multiple metabolic pathways, and the time course of these changes is different over 14 days of altitude exposure.


Assuntos
Altitude , Hipóxia/metabolismo , Metaboloma/fisiologia , Consumo de Oxigênio/fisiologia , Adulto , Feminino , Humanos , Masculino , Metabolômica/métodos , Descanso/fisiologia , Corrida/fisiologia , Adulto Jovem
15.
J Intensive Care ; 6: 60, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30214812

RESUMO

BACKGROUND: Both anaemia and red blood cell (RBC) transfusion are common and associated with adverse outcomes in patients admitted to the intensive care unit (ICU). The aim of this study was to determine whether serum hepcidin concentration, measured early after ICU admission in patients with anaemia, could identify a group in whom intravenous (IV) iron therapy decreased the subsequent RBC transfusion requirement. METHODS: We conducted a prospective observational study nested within a multicenter randomized controlled trial (RCT) of IV iron versus placebo. The study was conducted in the ICUs of four tertiary hospitals in Perth, Western Australia. Critically ill patients with haemoglobin (Hb) of < 100 g/L and within 48 h of admission to the ICU were eligible for participation after enrolment in the IRONMAN RCT. The response to IV iron therapy compared with placebo was assessed according to tertile of hepcidin concentration. RESULTS: Hepcidin concentration was measured within 48 h of ICU admission in 133 patients. For patients in the lower two tertiles of hepcidin concentration (< 53.0 µg), IV iron therapy compared with placebo was associated with a significant decrease in RBC transfusion requirement [risk ratio 0.48 (95% CI 0.26-0.85), p = 0.013]. CONCLUSIONS: In critically ill patients with anaemia admitted to an ICU, baseline hepcidin concentration predicts RBC transfusion requirement and is able to identify a group of patients in whom IV iron compared with placebo is associated with a significant decrease in RBC transfusion requirement. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry: ANZCTRN12612001249 Registered 26/11/2012.

16.
Hepatol Commun ; 2(6): 644-653, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29881816

RESUMO

Rodent and cell-culture models support a role for iron-related adipokine dysregulation and insulin resistance in the pathogenesis of nonalcoholic fatty liver disease (NAFLD); however, substantial human data are lacking. We examined the relationship between measures of iron status, adipokines, and insulin resistance in patients with NAFLD in the presence and absence of venesection. This study forms part of the Impact of Iron on Insulin Resistance and Liver Histology in Nonalcoholic Steatohepatitis (IIRON2) study, a prospective randomized controlled trial of venesection for adults with NAFLD. Paired serum samples at baseline and 6 months (end of treatment) in controls (n = 28) and patients who had venesection (n = 23) were assayed for adiponectin, leptin, resistin, retinol binding protein-4, tumor necrosis factor α, and interleukin-6, using a Quantibody, customized, multiplexed enzyme-linked immunosorbent assay array. Hepatic iron concentration (HIC) was determined using MR FerriScan. Unexpectedly, analysis revealed a significant positive correlation between baseline serum adiponectin concentration and HIC, which strengthened after correction for age, sex, and body mass index (rho = 0.36; P = 0.007). In addition, there were significant inverse correlations between HIC and measures of insulin resistance (adipose tissue insulin resistance (Adipo-IR), serum insulin, serum glucose, homeostasis model assessment of insulin resistance, hemoglobin A1c, and hepatic steatosis), whereas a positive correlation was noted with the insulin sensitivity index. Changes in serum adipokines over 6 months did not differ between the control and venesection groups. Conclusion: HIC positively correlates with serum adiponectin and insulin sensitivity in patients with NAFLD. Further study is required to establish causality and mechanistic explanations for these associations and their relevance in the pathogenesis of insulin resistance and NAFLD. (Hepatology Communications 2018;2:644-653).

17.
Sci Rep ; 8(1): 8188, 2018 05 29.
Artigo em Inglês | MEDLINE | ID: mdl-29844538

RESUMO

Chytridiomycosis is among several recently emerged fungal diseases of wildlife that have caused decline or extinction of naïve populations. Despite recent advances in understanding pathogenesis, host response to infection remains poorly understood. Here we modelled a total of 162 metabolites across skin and liver tissues of 61 frogs from four populations (three long-exposed and one naïve to the fungus) of the Australian alpine tree frog (Litoria verreauxii alpina) throughout a longitudinal exposure experiment involving both infected and negative control individuals. We found that chytridiomycosis dramatically altered the organism-wide metabolism of clinically diseased frogs. Chytridiomycosis caused catastrophic failure of normal homeostatic mechanisms (interruption of biosynthetic and degradation metabolic pathways), and pronounced dysregulation of cellular energy metabolism. Key intermediates of the tricarboxylic acid cycle were markedly depleted, including in particular α-ketoglutarate and glutamate that together constitute a key nutrient pathway for immune processes. This study was the first to apply a non-targeted metabolomics approach to a fungal wildlife disease and specifically to dissect the host-pathogen interface of Bd-infected frogs. The patterns of metabolite accumulation we have identified reveal whole-body metabolic dysfunction induced by a fungal skin infection, and these findings have broad relevance for other fungal diseases.


Assuntos
Animais Selvagens/metabolismo , Animais Selvagens/microbiologia , Anuros/metabolismo , Anuros/microbiologia , Quitridiomicetos/fisiologia , Dermatomicoses/veterinária , Metabolismo Energético , Animais , Austrália , Dermatomicoses/metabolismo , Feminino , Interações Hospedeiro-Patógeno , Fígado/metabolismo , Fígado/microbiologia , Masculino , Redes e Vias Metabólicas , Metaboloma , Pele/metabolismo , Pele/microbiologia
18.
Sci Data ; 5: 180033, 2018 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-29509187

RESUMO

The fungal skin disease chytridiomycosis has caused the devastating decline and extinction of hundreds of amphibian species globally, yet the potential for evolving resistance, and the underlying pathophysiological mechanisms remain poorly understood. We exposed 406 naïve, captive-raised alpine tree frogs (Litoria verreauxii alpina) from multiple populations (one evolutionarily naïve to chytridiomycosis) to the aetiological agent Batrachochytrium dendrobatidis in two concurrent and controlled infection experiments. We investigated (A) survival outcomes and clinical pathogen burdens between populations and clutches, and (B) individual host tissue responses to chytridiomycosis. Here we present multiple interrelated datasets associated with these exposure experiments, including animal signalment, survival and pathogen burden of 355 animals from Experiment A, and the following datasets related to 61 animals from Experiment B: animal signalment and pathogen burden; raw RNA-Seq reads from skin, liver and spleen tissues; de novo assembled transcriptomes for each tissue type; raw gene expression data; annotation data for each gene; and raw metabolite expression data from skin and liver tissues. These data provide an extensive baseline for future analyses.


Assuntos
Doenças dos Animais , Anuros , Quitridiomicetos , Micoses , Doenças dos Animais/genética , Doenças dos Animais/metabolismo , Doenças dos Animais/microbiologia , Doenças dos Animais/fisiopatologia , Animais , Micoses/genética , Micoses/metabolismo , Micoses/fisiopatologia
19.
Nephrology (Carlton) ; 22(7): 548-554, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27171136

RESUMO

BACKGROUND: Pentoxifylline has been shown to increase haemoglobin levels in patients with chronic kidney disease (CKD) and erythropoietin-stimulating agent (ESA)-hyporesponsive anaemia in the Handling Erythropoietin Resistance with Oxpentifylline multicentre double-blind, randomized controlled trial. The present sub-study evaluated the effects of pentoxifylline on the iron-regulatory hormone hepcidin in patients with ESA-hyporesponsive CKD. METHODS: This sub-study included 13 patients in the pentoxifylline arm (400 mg daily) and 13 in the matched placebo arm. Hepcidin-25 was measured by ultra performance liquid chromatography/quadrupole time-of-flight mass spectrometry following isolation from patient serum. Serum hepcidin-25, serum iron biomarkers, haemoglobin and ESA dosage were compared within and between the two groups. RESULTS: Hepcidin-25 concentration at 4 months adjusted for baseline did not differ significantly in pentoxifylline versus placebo treated patients (adjusted mean difference (MD) -7.9 nmol, P = 0.114), although the difference between the groups mean translated into a >25% reduction of circulating hepcidin-25 due to pentoxifylline compared with the placebo baseline. In paired analysis, serum hepcidin-25 levels were significantly decreased at 4 months compared with baseline in the pentoxifylline group (-5.47 ± 2.27 nmol/l, P < 0.05) but not in the placebo group (2.82 ± 4.29 nmol/l, P = 0.24). Pentoxifylline did not significantly alter serum ferritin (MD 55.4 mcg/l), transferrin saturation (MD 4.04%), the dosage of ESA (MD -9.93 U/kg per week) or haemoglobin concentration (MD 5.75 g/l). CONCLUSION: The reduction of circulating hepcidin-25 due to pentoxifylline did not reach statistical significance; however, the magnitude of the difference suggests that pentoxifylline may be a clinically and biologically meaningful modulator of hepcidin-25 in dialysis of patients with ESA-hyporesponsive anaemia.


Assuntos
Anemia/tratamento farmacológico , Darbepoetina alfa/uso terapêutico , Resistência a Medicamentos , Eritropoese/efeitos dos fármacos , Hematínicos/uso terapêutico , Hepcidinas/sangue , Pentoxifilina/uso terapêutico , Insuficiência Renal Crônica/terapia , Idoso , Idoso de 80 Anos ou mais , Anemia/sangue , Anemia/diagnóstico , Biomarcadores/sangue , Darbepoetina alfa/efeitos adversos , Método Duplo-Cego , Feminino , Hematínicos/efeitos adversos , Hemoglobinas/metabolismo , Humanos , Ferro/sangue , Masculino , Pessoa de Meia-Idade , Pentoxifilina/efeitos adversos , Insuficiência Renal Crônica/sangue , Insuficiência Renal Crônica/diagnóstico , Fatores de Tempo , Resultado do Tratamento
20.
Intensive Care Med ; 42(11): 1715-1722, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27686346

RESUMO

PURPOSE: Both anaemia and allogenic red blood cell transfusion are common and potentially harmful in patients admitted to the intensive care unit. Whilst intravenous iron may decrease anaemia and RBC transfusion requirement, the safety and efficacy of administering iron intravenously to critically ill patients is uncertain. METHODS: The multicentre, randomized, placebo-controlled, blinded Intravenous Iron or Placebo for Anaemia in Intensive Care (IRONMAN) study was designed to test the hypothesis that, in anaemic critically ill patients admitted to the intensive care unit, early administration of intravenous iron, compared with placebo, reduces allogeneic red blood cell transfusion during hospital stay and increases the haemoglobin level at the time of hospital discharge. RESULTS: Of 140 patients enrolled, 70 were assigned to intravenous iron and 70 to placebo. The iron group received 97 red blood cell units versus 136 red blood cell units in the placebo group, yielding an incidence rate ratio of 0.71 [95 % confidence interval (0.43-1.18), P = 0.19]. Overall, median haemoglobin at hospital discharge was significantly higher in the intravenous iron group than in the placebo group [107 (interquartile ratio IQR 97-115) vs. 100 g/L (IQR 89-111), P = 0.02]. There was no significant difference between the groups in any safety outcome. CONCLUSIONS: In patients admitted to the intensive care unit who were anaemic, intravenous iron, compared with placebo, did not result in a significant lowering of red blood cell transfusion requirement during hospital stay. Patients who received intravenous iron had a significantly higher haemoglobin concentration at hospital discharge. The trial was registered at http://www.anzctr.org.au as # ACTRN12612001249842.


Assuntos
Anemia/tratamento farmacológico , Transfusão de Eritrócitos/estatística & dados numéricos , Compostos Férricos/administração & dosagem , Hemoglobinas/análise , Maltose/análogos & derivados , Administração Intravenosa , Adulto , Idoso , Aloenxertos , Anemia/sangue , Intervalos de Confiança , Estado Terminal , Método Duplo-Cego , Feminino , Humanos , Unidades de Terapia Intensiva , Análise de Intenção de Tratamento , Masculino , Maltose/administração & dosagem , Pessoa de Meia-Idade
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