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1.
Eur J Neurosci ; 59(7): 1789-1818, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38221768

RESUMO

Stroke is one of the leading causes of adult disability affecting millions of people worldwide. Post-stroke cognitive and motor impairments diminish quality of life and functional independence. There is an increased risk of having a second stroke and developing secondary conditions with long-term social and economic impacts. With increasing number of stroke incidents, shortage of medical professionals and limited budgets, health services are struggling to provide a care that can break the vicious cycle of stroke. Effective post-stroke recovery hinges on holistic, integrative and personalized care starting from improved diagnosis and treatment in clinics to continuous rehabilitation and support in the community. To improve stroke care pathways, there have been growing efforts in discovering biomarkers that can provide valuable insights into the neural, physiological and biomechanical consequences of stroke and how patients respond to new interventions. In this review paper, we aim to summarize recent biomarker discovery research focusing on three modalities (brain imaging, blood sampling and gait assessments), look at some established and forthcoming biomarkers, and discuss their usefulness and complementarity within the context of comprehensive stroke care. We also emphasize the importance of biomarker guided personalized interventions to enhance stroke treatment and post-stroke recovery.


Assuntos
AVC Isquêmico , Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Adulto , Humanos , AVC Isquêmico/complicações , Qualidade de Vida , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/terapia , Reabilitação do Acidente Vascular Cerebral/métodos , Biomarcadores
2.
Metabolomics ; 20(1): 19, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38296869

RESUMO

INTRODUCTION: Tan Spot (TS) disease of wheat is caused by Pyrenophora tritici-repentis (Ptr), where most of the yield loss is linked to diseased flag leaves. As there are no fully resistant cultivars available, elucidating the responses of wheat to Ptr could inform the derivation of new resistant genotypes. OBJECTIVES: The study aimed to characterise the flag-leaf metabolomes of two spring wheat cultivars (Triticum aestivum L. cv. PF 080719 [PF] and cv. Fundacep Horizonte [FH]) following challenge with Ptr to gain insights into TS disease development. METHODS: PF and FH plants were inoculated with a Ptr strain that produces the necrotrophic toxin ToxA. The metabolic changes in flag leaves following challenge (24, 48, 72, and 96 h post-inoculation [hpi]) with Ptr were investigated using untargeted flow infusion ionisation-high resolution mass spectroscopy (FIE-HRMS). RESULTS: Both cultivars were susceptible to Ptr at the flag-leaf stage. Comparisons of Ptr- and mock-inoculated plants indicated that a major metabolic shift occurred at 24 hpi in FH, and at 48 hpi in PF. Although most altered metabolites were genotype specific, they were linked to common pathways; phenylpropanoid and flavonoid metabolism. Alterations in sugar metabolism as well as in glycolysis and glucogenesis pathways were also observed. Pathway enrichment analysis suggested that Ptr-triggered alterations in chloroplast and photosynthetic machinery in both cultivars, especially in FH at 96 hpi. In a wheat-Ptr interactome in integrative network analysis, "flavone and flavonol biosynthesis" and "starch and sucrose metabolism" were targeted as the key metabolic processes underlying PF-FH-Ptr interactions. CONCLUSION: These observations suggest the potential importance of flavone and flavonol biosynthesis as well as bioenergetic shifts in susceptibility to Ptr. This work highlights the value of metabolomic approaches to provide novel insights into wheat pathosystems.


Assuntos
Ascomicetos , Flavonas , Triticum , Metabolômica , Flavonóis , Açúcares
3.
Cancers (Basel) ; 15(18)2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37760494

RESUMO

Lung tumors frequently metastasize to the brain. Brain metastasis (BM) is common in advanced cases, and a major cause of patient morbidity and mortality. The precise molecular mechanisms governing BM are still unclear, in part attributed to the rarity of BM specimens. In this work, we compile a unique transcriptomic dataset encompassing RNA-seq, microarray, and single-cell analyses from BM samples obtained from patients with lung adenocarcinoma (LUAD). By integrating this comprehensive dataset, we aimed to enhance understanding of the molecular landscape of BM, thereby facilitating the identification of novel and efficient treatment strategies. We identified 102 genes with significantly deregulated expression levels in BM tissues, and discovered transcriptional alterations affecting the key driver 'hub' genes CD69 (a type II C-lectin receptor) and GZMA (Granzyme A), indicating an important role of the immune system in the development of BM from primary LUAD. Our study demonstrated a BM-specific gene expression pattern and revealed the presence of dendritic cells and neutrophils in BM, suggesting an immunosuppressive tumor microenvironment. These findings highlight key drivers of LUAD-BM that may yield therapeutic targets to improve patient outcomes.

4.
Environ Microbiol ; 25(11): 2549-2563, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37621052

RESUMO

Glaciers host ecosystems comprised of biodiverse and active microbiota. Among glacial ecosystems, less is known about the ecology of ice caps since most studies focus on valley glaciers or ice sheet margins. Previously we detailed the microbiota of one such high Arctic ice cap, focusing on cryoconite as a microbe-mineral aggregate formed by cyanobacteria. Here, we employ metabolomics at the scale of an entire ice cap to reveal the major metabolic pathways prevailing in the cryoconite of Foxfonna, central Svalbard. We reveal how geophysical and biotic processes influence the metabolomes of its resident cryoconite microbiota. We observed differences in amino acid, fatty acid, and nucleotide synthesis across the cap reflecting the influence of ice topography and the cyanobacteria within cryoconite. Ice topography influences central carbohydrate metabolism and nitrogen assimilation, whereas bacterial community structure governs lipid, nucleotide, and carotenoid biosynthesis processes. The prominence of polyamine metabolism and nitrogen assimilation highlights the importance of recycling nitrogenous nutrients. To our knowledge, this study represents the first application of metabolomics across an entire ice mass, demonstrating its utility as a tool for revealing the fundamental metabolic processes essential for sustaining life in supraglacial ecosystems experiencing profound change due to Arctic climate change-driven mass loss.


Assuntos
Cianobactérias , Microbiota , Ecossistema , Ecologia , Regiões Árticas , Camada de Gelo/microbiologia , Nitrogênio , Nucleotídeos
5.
Planta ; 258(3): 67, 2023 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-37597049

RESUMO

MAIN CONCLUSION: Salinity induced metabolite responses resulted in differential accumulation of flavonoids and antioxidant metabolites in shoots and roots suggesting improved antioxidant capacity in providing salt-adaptive phenotype of tef seedling. Tef [(Eragrostis tef) (Zucc.) Trotter] is an important 'cash crop' of Ethiopia grown mainly for human food, and development of elite tef cultivars with better performance is vital to Ethiopian farmers and breeders. Soil salinity is one of the key constraints that affects tef yield in the Ethiopian lowlands and Rift valley where cultivation of tef is limited. Being a minor crop, the responses of tef towards salinity is unknown. Salinity involves physiological and metabolite reprogramming that can have major impact on germination and seedling establishment. Here we evaluate the in vitro effect of NaCl on tef germination and associate this with metabolomic approaches to suggest salt tolerance mechanisms. In this study, 19 tef varieties were screened for NaCl tolerance and were investigated using untargeted metabolomics. Screened tef varieties showed differential germination rates with NaCl treatment varying from < 20 to 100%. Viable seedlings exposed to NaCl exhibited purple-red pigment accumulation in the roots except for Beten and Tullu nasy varieties. Metabolite comparisons between shoots and roots showed significant differences and, in particular, roots of salt tolerant tef varieties accumulated flavonoid derivatives as well as sugars and cell wall associated metabolites. These metabolic changes were correlated with patterns of antioxidant capacities and total flavonoid content in shoots and roots and suggested a mitigating response by tef to salinity. Our study highlights the role of flavonoid accumulation following salt stress on tef seedlings and further these findings could be used as targets for selective tef breeding.


Assuntos
Eragrostis , Germinação , Humanos , Antioxidantes , Salinidade , Cloreto de Sódio/farmacologia , Metabolômica , Plântula , Flavonoides
6.
Eur J Nutr ; 62(7): 2977-2990, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37458775

RESUMO

PURPOSE: The influence of vitamin D status on exercise-induced immune dysfunction remains unclear. The aim of this study was to investigate the effects of vitamin D status (circulating 25(OH)D) on innate immune responses and metabolomic profiles to prolonged exercise. METHODS: Twenty three healthy, recreationally active males (age 25 ± 7 years; maximal oxygen uptake [[Formula: see text]max] 56 ± 9 mL·kg-1·min-1), classified as being deficient (n = 7) or non-deficient n = 16) according to plasma concentrations of 25(OH)D, completed 2.5 h of cycling at 15% Δ (~ 55-60% [Formula: see text]max). Venous blood and unstimulated saliva samples were obtained before and after exercise. RESULTS: Participants with deficient plasma 25(OH)D on average had lower total lymphocyte count (mean difference [95% confidence interval], 0.5 cells × 109 L [0.1, 0.9]), p = 0.013) and greater neutrophil:lymphocyte ratio (1.3 cells × 109 L, [0.1, 2.5], p = 0.033). The deficient group experienced reductions from pre-exercise to 1 h post-exercise (- 43% [- 70, - 15], p = 0.003) in bacterial stimulated elastase in blood neutrophils compared to non-deficient participants (1% [- 20, 21], p = 1.000) Multivariate analyses of plasma metabolomic profiles showed a clear separation of participants according to vitamin D status. Prominent sources of variation between groups were purine/pyrimidine catabolites, inflammatory markers (linoleic acid pathway), lactate and tyrosine/adrenaline. CONCLUSION: These findings provide evidence of the influence of vitamin D status on exercise-induced changes in parameters of innate immune defence and metabolomic signatures such as markers of inflammation and metabolic stress.


Assuntos
Imunidade Inata , Vitamina D , Masculino , Humanos , Adolescente , Adulto Jovem , Adulto , Vitaminas , Exercício Físico/fisiologia , Neutrófilos
8.
Front Plant Sci ; 14: 1171773, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37287714

RESUMO

Introduction: Pearl millet is a staple cereal grown in the harshest environments of arid and semi-arid regions of Asia and sub-Saharan Africa. It is the primary source of calories for millions of people in these regions because it has better adaptation to harsh environmental conditions and better nutritional traits than many other cereals. By screening the pearl millet inbred germplasm association panel (PMiGAP), we earlier reported the best genotypes with the highest concentration of slowly digestible and resistant starch in their grains. Methods: In the current study, we tested these 20 top-performing pearl millet hybrids, identified based on starch data, in a randomised block design with three replications at five locations in West Africa, viz. Sadore and Konni (Niger), Bambey (Senegal), Kano (Nigeria), and Bawku (Ghana). Phenotypic variability was assessed for agronomic traits and mineral traits (Fe and Zn). Results and discussion: Analysis of variance demonstrated significant genotypic, environmental, and GEI effects among five testing environments for agronomic traits (days to 50% flowering, panicle length, and grain yield), starch traits (rapidly digestible starch, slowly digestible starch, resistant starch, and total starch), and mineral trait (iron and zinc). Starch traits, such as rapidly digestible starch (RDS) and slowly digestible starch (SDS), showed nonsignificant genotypic and environmental interactions but high heritability, indicating the lower environmental influence on these traits in the genotype × testing environments. Genotype stability and mean performance across all the traits were estimated by calculating the multi-trait stability index (MTSI), which showed that genotypes G3 (ICMX207070), G8 (ICMX207160), and G13 (ICMX207184) were the best performing and most stable among the five test environments.

9.
Int J Mol Sci ; 24(5)2023 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-36902282

RESUMO

Understanding the impact of long-term physiological and environmental stress on the human microbiota and metabolome may be important for the success of space flight. This work is logistically difficult and has a limited number of available participants. Terrestrial analogies present important opportunities to understand changes in the microbiota and metabolome and how this may impact participant health and fitness. Here, we present work from one such analogy: the Transarctic Winter Traverse expedition, which we believe is the first assessment of the microbiota and metabolome from different bodily locations during prolonged environmental and physiological stress. Bacterial load and diversity were significantly higher during the expedition when compared with baseline levels (p < 0.001) in saliva but not stool, and only a single operational taxonomic unit assigned to the Ruminococcaceae family shows significantly altered levels in stool (p < 0.001). Metabolite fingerprints show the maintenance of individual differences across saliva, stool, and plasma samples when analysed using flow infusion electrospray mass spectrometry and Fourier transform infrared spectroscopy. Significant activity-associated changes in terms of both bacterial diversity and load are seen in saliva but not in stool, and participant differences in metabolite fingerprints persist across all three sample types.


Assuntos
Expedições , Microbiota , Humanos , Saliva/metabolismo , Carga Bacteriana , Regiões Antárticas , Individualidade , Microbiota/fisiologia , Metaboloma/fisiologia , Fezes/microbiologia , RNA Ribossômico 16S/metabolismo
10.
Mol Ecol Resour ; 23(1): 253-272, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35932461

RESUMO

Locoweeds are perennial forbs poisonous to livestock and cause extreme losses to animal husbandry. Locoweed toxicity is attributed to the symbiotic endophytes in Alternaria sect. Undifilum, which produce a mycotoxin swainsonine (SW). We performed a de novo whole genome sequencing of the most common locoweed in China, Oxytropis ochrocephala (2n = 16), and assembled a high-quality, chromosome-level reference genome. Its genome size is 958.83 Mb with 930.94 Mb (97.09%) anchored and oriented onto eight chromosomes, and 31,700 protein-coding genes were annotated. Phylogenetic and collinearity analysis showed it is closely related to Medicago truncatula with a pair of large interchromosomal rearrangements, and both species underwent a whole-genome duplication event. We also derived the genome of A. oxytropis at 74.48 Mb with a contig N50 of 8.87 Mb and 10,657 protein-coding genes, and refined the genes of SW biosynthesis. Multiple Alternaria species containing the swnK gene were grouped into a single clade, but in other genera, swnK's homologues are diverse. Resequencing of 41 A. oxytropis strains revealed one SNP in the SWN cluster causing changes in SW concentration. Comparing the transcriptomes of symbiotic and nonsymbiotic interactions identified differentially expressed genes (DEGs) linked to defence and secondary metabolism in the host. Within the endophyte DEGs were linked to cell wall degradation, fatty acids and nitrogen metabolism. Symbiosis induced the upregulation of most of the SW biosynthetic genes. These two genomes and relevant sequencing data should provide valuable genetic resources for the study of the evolution, interaction, and SW biosynthesis in the symbiont.


Assuntos
Ascomicetos , Oxytropis , Swainsonina/análise , Swainsonina/metabolismo , Oxytropis/genética , Oxytropis/metabolismo , Endófitos/genética , Endófitos/metabolismo , Alternaria/genética , Alternaria/metabolismo , Simbiose/genética , Filogenia , Ascomicetos/metabolismo
12.
J Exp Bot ; 74(3): 931-944, 2023 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-36306203

RESUMO

Locoweeds are leguminous forbs known for their toxicity to livestock caused by the endophytic fungi Alternaria sect. Undifilum. Unlike the defensive mutualisms reported in many toxin-producing endophytes and their plant hosts, the benefits that A. sect. Undifilum can confer to it host plants remains unclear. Here, we conducted physiological and genetic analyses to show that A. (sect. Undifilum) oxytropis influences growth, especially root development, in its locoweed host Oxytropis ochrocephala and Arabidopsis. The presence of A. oxytropis significantly decreased primary root length while increasing the numbers of lateral roots and root hairs, and increasing plant leaf area and fresh weight. The fungus also increased the concentrations of plant endogenous auxin, and the expression of key genes for auxin biosynthesis, signaling, and transport. These effects on root development were abolished in mutants deficient in auxin signaling and polar transport. Alternaria oxytropis down-regulated expression of PIN1 but increased expression of PIN2, PIN7, and AUX1, which might reflect alterations in the spatial accumulation of auxin responsible for the changes in root architecture. Plant growth was insensitive to A. oxytropis when naphthylphthalamic acid was applied. Our findings indicate a function of A. oxytropis in promoting the growth and development of Arabidopsis via the regulation of auxin, which in turn suggests a possible role in benefiting its locoweed hosts via a process independent of its toxin production.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Endófitos/fisiologia , Alternaria , Arabidopsis/metabolismo , Swainsonina/análise , Swainsonina/metabolismo , Ácidos Indolacéticos/metabolismo , Raízes de Plantas/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo
13.
Front Pharmacol ; 13: 961087, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36339560

RESUMO

Traditional Chinese medicine (TCM) has been used to treat infectious diseases and could offer potential drug leads. This study evaluates the in vitro antimicrobial activities from commercially sourced Dryopteris crassirhizoma Nakai (Polypodiaceae) whose authenticity was confirmed by DNA barcoding based on the ribulose bisphosphate carboxylase (rbcL) gene. Powdered rhizomes were sequentially extracted using n-hexane, dichloromethane, ethyl acetate, and methanol at ambient temperature. The dried extracts at different concentrations were tested for antimicrobial activities against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, methicillin-resistant Staphylococcus aureus (MRSA), and Mycobacterium smegmatis. D. crassirhizoma extracts exhibited significant antimicrobial activities only against MRSA (minimum inhibitory concentration: 3.125 µg/ml n-hexane extract). Activity-led fractionations of D. crassirhizoma and characterization by ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) targeted a fraction (A3), with two anti-MRSA phloroglucinol derivatives, flavaspidic acid AB and norflavaspidic acid AB-being greatly enriched in the latter. The impact of A3 on MRSA cells was examined using untargeted metabolomic analysis and compared to that of other established antibiotics (all treatments normalized to MIC50 at 6 h). This suggested that norflavaspidic acid AB had distinctive effects, one of which involved targeting bioenergetic transformation, metabolism, and particularly acetyl-CoA, on MRSA cells. No cytotoxicity was observed for the norflavaspidic acid AB-enriched fraction against murine HepG2 cells. This study requires further experimental validation but can have indicated a naturally available compound that could help counter the threat of clinically relevant strains with antibiotic resistance.

14.
Curr Microbiol ; 79(12): 363, 2022 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-36253492

RESUMO

Here we investigate the faecal microbiome of wild European badgers Meles meles using samples collected at post-mortem as part of the All Wales Badger Found Dead study. This is the first published characterisation of the badger microbiome. We initially undertook a sex-matched age comparison between the adult and cub microbiomes, based on sequencing the V3-V4 region of the 16S rRNA gene. Analysis used the QIIME 2 pipeline utilising DADA2 and the Silva database for taxonomy assignment. Fusobacteria appeared to be more abundant in the microbiomes of the cubs than the adults although no significant difference was seen in alpha or beta diversity between the adult and cub badger microbiomes. Comparisons were also made against other wild, omnivorous, mammals' faecal microbiomes using publicly available data. Significant differences were seen in both alpha and beta diversity between the microbiomes from different species. As a wildlife species of interest to the disease bovine tuberculosis, knowledge of the faecal microbiome could assist in identification of infected badgers. Our work here suggests that, if comparisons were made between the faeces of bTB infected and non-infected badgers, age may not have a significant impact on the microbiome.


Assuntos
Microbiota , Mustelidae , Tuberculose Bovina , Animais , Bovinos , Fezes/microbiologia , Mustelidae/microbiologia , RNA Ribossômico 16S/genética , Tuberculose Bovina/microbiologia
15.
Front Plant Sci ; 13: 979956, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36262663

RESUMO

The halophyte Karelinia caspia has not only fodder and medical value but also can remediate saline-alkali soils. Our previous study showed that salt-secreting by salt glands is one of main adaptive strategies of K. caspia under high salinity. However, ROS scavenging, ion homeostasis, and photosynthetic characteristics responses to high salinity remain unclear in K. caspia. Here, physio-biochemical responses and gene expression associated with ROS scavenging and ions transport were tested in K. caspia subjected to 100-400 mM NaCl for 7 days. Results showed that both antioxidant enzymes (SOD, APX) activities and non-enzymatic antioxidants (chlorogenic acid, α-tocopherol, flavonoids, polyamines) contents were significantly enhanced, accompanied by up-regulating the related enzyme and non-enzymatic antioxidant synthesis gene (KcCu/Zn-SOD, KcAPX6, KcHCT, KcHPT1, Kcγ-TMT, KcF3H, KcSAMS and KcSMS) expression with increasing concentrations of NaCl. These responses are beneficial for removing excess ROS to maintain a stable level of H2O2 and O2 - without lipid peroxidation in the K. caspia response to high salt. Meanwhile, up-regulating expression of KcSOS1/2/3, KcNHX1, and KcAVP was linked to Na+ compartmentalization into vacuoles or excretion through salt glands in K. caspia. Notably, salt can improve the function of PSII that facilitate net photosynthetic rates, which is helpful to growing normally in high saline. Overall, the findings suggested that ROS scavenging systems and Na+/K+ transport synergistically contributed to redox equilibrium, ion homeostasis, and the enhancement of PSII function, thereby conferring high salt tolerance.

16.
Cells ; 11(19)2022 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-36231070

RESUMO

Genotype × environment interactions (GEIs) should play an important role in the selection of suitable germplasm in breeding programmes. We here assessed GEI effects on pearl millet (Pennisetum glaucum L.) genotypes, selected to possess a high concentration of slowly digestible starch (SDS) and resistant starch (RS) in their grains. Entries were grown in a randomized complete block design with three replications at locations in Bawku-Ghana, Sadore-Niger, Bamako-Mali, Konni-Nigeria, and Gampella-Burkina Faso across West Africa. Harvested grains from these locations were metabolomically profiled using flow injection ionization-high-resolution mass spectrometry (FIE-HRMS). A total of 3144 mass features (m/z) (1560 negative ion mode and 1584 positive ion mode) were detected, of which, 475 m/z were linked to metabolites be involved in starch, antioxidant and lipid biosynthesis, and vitamin metabolism. Combined ANOVA revealed that the GEI was significantly evident for 54 health-benefiting metabolites, many associated with sugar, especially galactose, metabolism. Additive main effects and multiplicative interaction (AMMI) analysis examined genotype variation and GEI effects, which, when combined with principal component analysis (PCA), found that m/z 171.14864 (positive ionisation, propenyl heptanoate) accounted for 89% of the GEI variation along PC1. The AMMI-based stability parameter (ASTAB), modified AMMI stability value (MASV), and modified AMMI stability index (MASI) were then applied to identify stable and high-performing genotypes for all the health-benefiting metabolites. Similarly, the best-linear-unbiased-prediction (BLUP)-based stability estimation was also performed using the harmonic mean of genotypic values (HMGV), relative performance of genotypic values (RPGV), and harmonic mean of relative performance of genotypic values (HMRPGV), to identify genotype rankings across multiple environments. The multi-trait stability index (MTSI) was calculated and found that the genotypes G1 (ICMH-177111) and G24 (ICMX-207137) were the most stable and were the best mean performers across 52 health-benefiting metabolic traits. These findings demonstrate the potential of G × E assessments on the delivery of health-benefiting metabolite-rich grains in future varieties and hybrids of pearl millet.


Assuntos
Pennisetum , Antioxidantes , Galactose , Interação Gene-Ambiente , Genótipo , Heptanoatos , Pennisetum/genética , Amido Resistente , Amido , Vitaminas
17.
Vet Res ; 53(1): 68, 2022 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-36056402

RESUMO

Mycobacterium avium subspecies paratuberculosis (MAP) is the causative organism of Johne's disease, a chronic granulomatous enteritis of ruminants. We have previously used naturally MAP-infected heifer calves to document metabolomic changes occurring in MAP infections. Herein, we used experimentally MAP-inoculated heifer calves to identify biomarkers for MAP infections. At 2-weeks of age, 20 Holstein-Friesian (HF) calves were experimentally inoculated with MAP. These calves, along with 20 control calves, were sampled biweekly up to 13-months of age and then monthly up to 19-months of age. Sera were assessed using flow infusion electrospray high-resolution mass spectrometry (FIE-HRMS) on a Q Exactive hybrid quadrupole-Orbitrap mass spectrometer for high throughput, sensitive, non-targeted metabolite fingerprinting. Partial least squares-discriminate analysis (PLS-DA) and hierarchical cluster analysis (HCA) discriminated between MAP-inoculated and control heifer calves. Out of 34 identified metabolites, six fatty acyls were able to differentiate between experimental groups throughout the study, including 8, 11, 14-eicosatrienoic acid and cis-8, 11, 14, 17-eicosatetraenoic acid which were also detected in our previous study and so further suggested their value as biomarkers for MAP infection. Pathway analysis highlighted the role of the alpha-linoleic acid and linoleic acid metabolism. Within these pathways, two broad types of response, with a rapid increase in some saturated fatty acids and some n-3 polyunsaturated fatty acids (PUFAs) and later n-6 PUFAs, became predominant. This could indicate an initial anti-inflammatory colonisation phase, followed by an inflammatory phase. This study demonstrates the validity of the metabolomic approach in studying MAP infections. Nevertheless, further work is required to define further key events, particularly at a cell-specific level.


Assuntos
Doenças dos Bovinos , Mycobacterium avium subsp. paratuberculosis , Paratuberculose , Animais , Biomarcadores , Bovinos , Doenças dos Bovinos/microbiologia , Eicosanoides , Ácidos Graxos Insaturados , Feminino , Ácidos Linoleicos , Mycobacterium avium subsp. paratuberculosis/fisiologia , Paratuberculose/diagnóstico , Paratuberculose/microbiologia
18.
Comput Methods Programs Biomed ; 225: 107095, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36057226

RESUMO

BACKGROUND AND OBJECTIVE: Recent studies have shown that colorectal cancer (CRC) patients with microsatellite instability high (MSI-H) are more likely to benefit from immunotherapy. However, current MSI testing methods are not available for all patients due to the lack of available equipment and trained personnel, as well as the high cost of the assay. Here, we developed an improved deep learning model to predict MSI-H in CRC from whole slide images (WSIs). METHODS: We established the MSI-H prediction model based on two stages: tumor detection and MSI classification. Previous works applied fine-tuning strategy directly for tumor detection, but ignoring the challenge of vanishing gradient due to the large number of convolutional layers. We added auxiliary classifiers to intermediate layers of pre-trained models to help propagate gradients back through in an effective manner. To predict MSI status, we constructed a pair-wise learning model with a synergic network, named parameter partial sharing network (PPsNet), where partial parameters are shared among two deep convolutional neural networks (DCNNs). The proposed PPsNet contained fewer parameters and reduced the problem of intra-class variation and inter-class similarity. We validated the proposed model on a holdout test set and two external test sets. RESULTS: 144 H&E-stained WSIs from 144 CRC patients (81 cases with MSI-H and 63 cases with MSI-L/MSS) were collected retrospectively from three hospitals. The experimental results indicate that deep supervision based fine-tuning almost outperforms training from scratch and utilizing fine-tuning directly. The proposed PPsNet always achieves better accuracy and area under the receiver operating characteristic curve (AUC) than other solutions with four different neural network architectures on validation. The proposed method finally achieves obvious improvements than other state-of-the-art methods on the validation dataset with an accuracy of 87.28% and AUC of 94.29%. CONCLUSIONS: The proposed method can obviously increase model performance and our model yields better performance than other methods. Additionally, this work also demonstrates the feasibility of MSI-H prediction using digital pathology images based on deep learning in the Asian population. It is hoped that this model could serve as an auxiliary tool to identify CRC patients with MSI-H more time-saving and efficiently.


Assuntos
Neoplasias Colorretais , Aprendizado Profundo , Neoplasias Colorretais/diagnóstico por imagem , Neoplasias Colorretais/genética , Humanos , Instabilidade de Microssatélites , Redes Neurais de Computação , Estudos Retrospectivos
19.
NPJ Biofilms Microbiomes ; 8(1): 70, 2022 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-36038584

RESUMO

Microbiomes are rife for biotechnological exploitation, particularly the rumen microbiome, due to their complexicity and diversity. In this study, antimicrobial peptides (AMPs) from the rumen microbiome (Lynronne 1, 2, 3 and P15s) were assessed for their therapeutic potential against seven clinical strains of Pseudomonas aeruginosa. All AMPs exhibited antimicrobial activity against all strains, with minimum inhibitory concentrations (MICs) ranging from 4-512 µg/mL. Time-kill kinetics of all AMPs at 3× MIC values against strains PAO1 and LES431 showed complete kill within 10 min to 4 h, although P15s was not bactericidal against PAO1. All AMPs significantly inhibited biofilm formation by strains PAO1 and LES431, and induction of resistance assays showed no decrease in activity against these strains. AMP cytotoxicity against human lung cells was also minimal. In terms of mechanism of action, the AMPs showed affinity towards PAO1 and LES431 bacterial membrane lipids, efficiently permeabilising the P. aeruginosa membrane. Transcriptome and metabolome analysis revealed increased catalytic activity at the cell membrane and promotion of ß-oxidation of fatty acids. Finally, tests performed with the Galleria mellonella infection model showed that Lynronne 1 and 2 were efficacious in vivo, with a 100% survival rate following treatment at 32 mg/kg and 128 mg/kg, respectively. This study illustrates the therapeutic potential of microbiome-derived AMPs against P. aeruginosa infections.


Assuntos
Microbiota , Infecções por Pseudomonas , Animais , Peptídeos Catiônicos Antimicrobianos/farmacologia , Peptídeos Antimicrobianos , Humanos , Infecções por Pseudomonas/tratamento farmacológico , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa
20.
Metabolomics ; 18(8): 61, 2022 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-35896834

RESUMO

INTRODUCTION: Mycobacterium bovis, the causative agent of bovine tuberculosis (bTB) in cattle, represents a major disease burden to UK cattle farming, with considerable costs associated with its control. The European badger (Meles meles) is a known wildlife reservoir for bTB and better knowledge of the epidemiology of bTB through testing wildlife is required for disease control. Current tests available for the diagnosis of bTB in badgers are limited by cost, processing time or sensitivities. MATERIALS AND METHODS: We assessed the ability of flow infusion electrospray-high-resolution mass spectrometry (FIE-HRMS) to determine potential differences between infected and non-infected badgers based on thoracic blood samples obtained from badgers found dead in Wales. Thoracic blood samples were autoclaved for handling in a containment level 2 (CL2) hazard laboratory. RESULTS: Here we show the major differences associated with with M. bovis infection were changes to folate, pyrimidine, histidine, glycerophospholipid and phosphonate metabolism. CONCLUSIONS: Our studies have indicated differences in the metabolomic signature of badgers found dead in relation to their infection status, suggesting metabolomics could hold potential for developing novel diagnostics for bTB in badgers. As well as highlighting a potential way to handle samples containing a highly pathogenic agent at CL2 for metabolomics studies.


Assuntos
Mustelidae , Mycobacterium bovis , Tuberculose Bovina , Animais , Bovinos , Metabolômica , Mustelidae/microbiologia , Projetos Piloto , Tuberculose Bovina/diagnóstico , Tuberculose Bovina/epidemiologia , Tuberculose Bovina/microbiologia
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