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1.
Proc Natl Acad Sci U S A ; 118(48)2021 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-34815339

RESUMO

Cytokinin (CK) in plants regulates both developmental processes and adaptation to environmental stresses. Arabidopsis histidine phosphotransfer ahp2,3,5 and type-B Arabidopsis response regulator arr1,10,12 triple mutants are almost completely defective in CK signaling, and the ahp2,3,5 mutant was reported to be salt tolerant. Here, we demonstrate that the arr1,10,12 mutant is also more tolerant to salt stress than wild-type (WT) plants. A comprehensive metabolite profiling coupled with transcriptome analysis of the ahp2,3,5 and arr1,10,12 mutants was conducted to elucidate the salt tolerance mechanisms mediated by CK signaling. Numerous primary (e.g., sugars, amino acids, and lipids) and secondary (e.g., flavonoids and sterols) metabolites accumulated in these mutants under nonsaline and saline conditions, suggesting that both prestress and poststress accumulations of stress-related metabolites contribute to improved salt tolerance in CK-signaling mutants. Specifically, the levels of sugars (e.g., trehalose and galactinol), amino acids (e.g., branched-chain amino acids and γ-aminobutyric acid), anthocyanins, sterols, and unsaturated triacylglycerols were higher in the mutant plants than in WT plants. Notably, the reprograming of flavonoid and lipid pools was highly coordinated and concomitant with the changes in transcriptional levels, indicating that these metabolic pathways are transcriptionally regulated by CK signaling. The discovery of the regulatory role of CK signaling on membrane lipid reprogramming provides a greater understanding of CK-mediated salt tolerance in plants. This knowledge will contribute to the development of salt-tolerant crops with the ability to withstand salinity as a key driver to ensure global food security in the era of climate crisis.


Assuntos
Citocininas/metabolismo , Estresse Salino/genética , Adaptação Fisiológica/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Citocininas/fisiologia , Flavonoides/genética , Flavonoides/metabolismo , Expressão Gênica/genética , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/genética , Regulação da Expressão Gênica de Plantas/genética , Redes Reguladoras de Genes/genética , Metabolismo dos Lipídeos/genética , Metabolismo dos Lipídeos/fisiologia , Lipídeos/fisiologia , Metabolômica/métodos , Salinidade , Estresse Salino/fisiologia , Tolerância ao Sal/genética , Transdução de Sinais/fisiologia , Estresse Fisiológico/genética
2.
Sensors (Basel) ; 24(11)2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38894349

RESUMO

This paper proposes a fault-tolerant control (FTC) strategy using the current space vectors to diagnose sensor failures and enhance the sustained operation of a field-oriented (FO) controlled induction motor drive (IMD). Three space vectors are established for the sensor fault diagnosis technique, including one converted from the measured currents and the other two calculated from the current estimation technique, respectively, measured and with reference speeds. A mixed mathematical model using three space vectors and their components is proposed to accurately determine the fault condition of each sensor in the motor drive. After determining the operating status of each sensor, if the sensor signal is in good condition, the feedback signal to the controller will be the measured signal; otherwise, the estimated signal will be used instead of the failed signal. Failure states of the various sensors were simulated to check the effectiveness of the proposed technique in the Matlab/Simulink environment. The simulation results are positive: the IMD system applying the proposed FTC technique accurately detected the failed sensor and maintained stability during the operation.

3.
Plant J ; 111(6): 1732-1752, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35883014

RESUMO

Cytokinin plays an important role in plant stress responses via a multistep signaling pathway, involving the histidine phosphotransfer proteins (HPs). In Arabidopsis thaliana, the AHP2, AHP3 and AHP5 proteins are known to affect drought responses; however, the role of AHP4 in drought adaptation remains undetermined. In the present study, using a loss-of-function approach we showed that AHP4 possesses an important role in the response of Arabidopsis to drought. This is evidenced by the higher survival rates of ahp4 than wild-type (WT) plants under drought conditions, which is accompanied by the downregulated AHP4 expression in WT during periods of dehydration. Comparative transcriptome analysis of ahp4 and WT plants revealed AHP4-mediated expression of several dehydration- and/or abscisic acid-responsive genes involved in modulation of various physiological and biochemical processes important for plant drought acclimation. In comparison with WT, ahp4 plants showed increased wax crystal accumulation in stems, thicker cuticles in leaves, greater sensitivity to exogenous abscisic acid at germination, narrow stomatal apertures, heightened leaf temperatures during dehydration, and longer root length under osmotic stress. In addition, ahp4 plants showed greater photosynthetic efficiency, lower levels of reactive oxygen species, reduced electrolyte leakage and lipid peroxidation, and increased anthocyanin contents under drought, when compared with WT. These differences displayed in ahp4 plants are likely due to upregulation of genes that encode enzymes involved in reactive oxygen species scavenging and non-enzymatic antioxidant metabolism. Overall, our findings suggest that AHP4 plays a crucial role in plant drought adaptation.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Ácido Abscísico/metabolismo , Antocianinas/metabolismo , Antioxidantes/metabolismo , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Citocininas/metabolismo , Desidratação , Secas , Regulação da Expressão Gênica de Plantas , Histidina/genética , Histidina/metabolismo , Plantas Geneticamente Modificadas/genética , Espécies Reativas de Oxigênio/metabolismo , Estresse Fisiológico/genética
4.
Plant Cell Physiol ; 63(12): 1914-1926, 2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-35880749

RESUMO

In this study, we investigated the potential role of the karrikin receptor KARRIKIN INSENSITIVE2 (KAI2) in the response of Arabidopsis seedlings to high-temperature stress. We performed phenotypic, physiological and transcriptome analyses of Arabidopsis kai2 mutants and wild-type (WT) plants under control (kai2_C and WT_C, respectively) and 6- and 24-h heat stress conditions (kai2_H6, kai2_H24, WT_H6 and WT_H24, respectively) to understand the basis for KAI2-regulated heat stress tolerance. We discovered that the kai2 mutants exhibited hypersensitivity to high-temperature stress relative to WT plants, which might be associated with a more highly increased leaf surface temperature and cell membrane damage in kai2 mutant plants. Next, we performed comparative transcriptome analysis of kai2_C, kai2_H6, kai2_H24, WT_C, WT_H6 and WT_H24 to identify transcriptome differences between WT and kai2 mutants in response to heat stress. K-mean clustering of normalized gene expression separated the investigated genotypes into three clusters based on heat-treated and non-treated control conditions. Within each cluster, the kai2 mutants were separated from WT plants, implying that kai2 mutants exhibited distinct transcriptome profiles relative to WT plants. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analyses showed a repression in 'misfolded protein binding', 'heat shock protein binding', 'unfolded protein binding' and 'protein processing in endoplasmic reticulum' pathways, which was consistent with the downregulation of several genes encoding heat shock proteins and heat shock transcription factors in the kai2 mutant versus WT plants under control and heat stress conditions. Our findings suggest that chemical or genetic manipulation of KAI2 signaling may provide a novel way to improve heat tolerance in plants.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Termotolerância , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Hidrolases/genética , Hidrolases/metabolismo , Resposta ao Choque Térmico/genética , Proteínas de Transporte/metabolismo , Regulação da Expressão Gênica de Plantas
5.
Plant Cell Physiol ; 63(12): 1927-1942, 2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-35997763

RESUMO

Plants activate a myriad of signaling cascades to tailor adaptive responses under environmental stresses, such as salinity. While the roles of exogenous karrikins (KARs) in salt stress mitigation are well comprehended, genetic evidence of KAR signaling during salinity responses in plants remains unresolved. Here, we explore the functions of the possible KAR receptor KARRIKIN-INSENSITIVE2 (KAI2) in Arabidopsis thaliana tolerance to salt stress by investigating comparative responses of wild-type (WT) and kai2-mutant plants under a gradient of NaCl. Defects in KAI2 functions resulted in delayed and inhibited cotyledon opening in kai2 seeds compared with WT seeds, suggesting that KAI2 played an important role in enhancing seed germination under salinity. Salt-stressed kai2 plants displayed more phenotypic aberrations, biomass reduction, water loss and oxidative damage than WT plants. kai2 shoots accumulated significantly more Na+ and thus had a lower K+/Na+ ratio, than WT, indicating severe ion toxicity in salt-stressed kai2 plants. Accordingly, kai2 plants displayed a lower expression of genes associated with Na+ homeostasis, such as SALT OVERLY SENSITIVE (SOS) 1, SOS2, HIGH-AFFINITY POTASSIUM TRANSPORTER 1;1 (HKT1;1) and CATION-HYDROGEN EXCHANGER 1 (NHX1) than WT plants. WT plants maintained a better glutathione level, glutathione-related redox status and antioxidant enzyme activities relative to kai2 plants, implying KAI2's function in oxidative stress mitigation in response to salinity. kai2 shoots had lower expression levels of genes involved in the biosynthesis of strigolactones (SLs), salicylic acid and jasmonic acid and the signaling of abscisic acid and SLs than those of WT plants, indicating interactive functions of KAI2 signaling with other hormone signaling in modulating plant responses to salinity. Collectively, these results underpin the likely roles of KAI2 in the alleviation of salinity effects in plants by regulating several physiological and biochemical mechanisms involved in ionic and osmotic balance, oxidative stress tolerance and hormonal crosstalk.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Tolerância ao Sal/genética , Proteínas de Transporte/metabolismo , Glutationa/metabolismo , Regulação da Expressão Gênica de Plantas
6.
Plant Cell Physiol ; 63(12): 1900-1913, 2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-35681253

RESUMO

Recent investigations in Arabidopsis thaliana suggest that SUPPRESSOR of MORE AXILLARY GROWTH 2 1 (SMAX1) and SMAX1-LIKE2 (SMXL2) are negative regulators of karrikin (KAR) and strigolactone (SL) signaling during plant growth and development, but their functions in drought resistance and related mechanisms of action remain unclear. To understand the roles and mechanisms of SMAX1 and SMXL2 in drought resistance, we investigated the drought-resistance phenotypes and transcriptome profiles of smax1 smxl2 (s1,2) double-mutant plants in response to drought stress. The s1,2 mutant plants showed enhanced drought-resistance and lower leaf water loss when compared with wild-type (WT) plants. Transcriptome comparison of rosette leaves from the s1,2 mutant and the WT under normal and dehydration conditions suggested that the mechanism related to cuticle formation was involved in drought resistance. This possibility was supported by enhanced cuticle formation in the rosette leaves of the s1,2 mutant. We also found that the s1,2 mutant plants were more sensitive to abscisic acid in assays of stomatal closure, cotyledon opening, chlorophyll degradation and growth inhibition, and they showed a higher reactive oxygen species detoxification capacity than WT plants. In addition, the s1,2 mutant plants had longer root hairs and a higher root-to-shoot ratio than the WT plants, suggesting that the mutant had a greater capacity for water absorption than the WT. Taken together, our results indicate that SMAX1 and SMXL2 negatively regulate drought resistance, and disruption of these KAR- and SL-signaling-related genes may therefore provide a novel means for improving crop drought resistance.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Resistência à Seca , Germinação/genética , Ácido Abscísico/metabolismo , Secas , Regulação da Expressão Gênica de Plantas , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo
7.
Plant Physiol ; 190(4): 2671-2687, 2022 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-35822606

RESUMO

The karrikin (KAR) receptor and several related signaling components have been identified by forward genetic screening, but only a few studies have reported on upstream and downstream KAR signaling components and their roles in drought tolerance. Here, we characterized the functions of KAR UPREGULATED F-BOX 1 (KUF1) in drought tolerance using a reverse genetics approach in Arabidopsis (Arabidopsis thaliana). We observed that kuf1 mutant plants were more tolerant to drought stress than wild-type (WT) plants. To clarify the mechanisms by which KUF1 negatively regulates drought tolerance, we performed physiological, transcriptome, and morphological analyses. We found that kuf1 plants limited leaf water loss by reducing stomatal aperture and cuticular permeability. In addition, kuf1 plants showed increased sensitivity of stomatal closure, seed germination, primary root growth, and leaf senescence to abscisic acid (ABA). Genome-wide transcriptome comparisons of kuf1 and WT rosette leaves before and after dehydration showed that the differences in various drought tolerance-related traits were accompanied by differences in the expression of genes associated with stomatal closure (e.g. OPEN STOMATA 1), lipid and fatty acid metabolism (e.g. WAX ESTER SYNTHASE), and ABA responsiveness (e.g. ABA-RESPONSIVE ELEMENT 3). The kuf1 mutant plants had higher root/shoot ratios and root hair densities than WT plants, suggesting that they could absorb more water than WT plants. Together, these results demonstrate that KUF1 negatively regulates drought tolerance by modulating various physiological traits, morphological adjustments, and ABA responses and that the genetic manipulation of KUF1 in crops is a potential means of enhancing their drought tolerance.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Secas , Proteínas de Arabidopsis/metabolismo , Estômatos de Plantas/fisiologia , Regulação da Expressão Gênica de Plantas , Estresse Fisiológico/genética , Ácido Abscísico/farmacologia , Ácido Abscísico/metabolismo , Água/metabolismo , Plantas Geneticamente Modificadas/metabolismo
8.
Drug Chem Toxicol ; 46(2): 281-296, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35707918

RESUMO

It has been recognized that serotonergic blocker showed serious side effects, and that ginsenoside modulated serotonergic system with the safety. However, the effects of ginsenoside on serotonergic impairments remain to be clarified. Thus, we investigated ginsenoside Re (GRe), a major bioactive component in the mountain-cultivated ginseng on (±)-8-hydroxy-dipropylaminotetralin (8-OH-DPAT), a 5-HT1A receptor agonist. In the present study, we observed that the treatment with GRe resulted in significant inhibition of protein kinase C δ (PKCδ) phosphorylation induced by the 5-HT1A receptor agonist (±)-8-hydroxy-dipropylaminotetralin (8-OH-DPAT) in the hypothalamus of the wild-type (WT) mice. The inhibition of GRe was comparable with that of the PKCδ inhibitor rottlerin or the 5-HT1A receptor antagonist WAY100635 (WAY). 8-OH-DPAT-induced significant reduction in nuclear factor erythroid-2-related factor 2 (Nrf2)-related system (i.e., Nrf2 DNA binding activity, γ-glutamylcysteine ligase modifier (GCLm) and γ-glutamylcysteine ligase catalytic (GCLc) mRNA expression, and glutathione (GSH)/oxidized glutathione (GSSG) ratio) was significantly attenuated by GRe, rottlerin, or WAY in WT mice. However, PKCδ gene knockout significantly protected the Nrf2-dependent system from 8-OH-DPAT insult in mice. Increases in 5-hydroxytryptophan (5-HT) turnover rate, overall serotonergic behavioral score, and hypothermia induced by 8-OH-DPAT were significantly attenuated by GRe, rottlerin, or WAY in WT mice. Consistently, PKCδ gene knockout significantly attenuated these parameters in mice. However, GRe or WAY did not provide any additional positive effects on the serotonergic protective potential mediated by PKCδ gene knockout in mice. Therefore, our results suggest that PKCδ is an important mediator for GRe-mediated protective activity against serotonergic impairments/oxidative burden caused by the 5-HT1A receptor.


Assuntos
Ginsenosídeos , Camundongos , Animais , 8-Hidroxi-2-(di-n-propilamino)tetralina/farmacologia , Ginsenosídeos/farmacologia , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Receptor 5-HT1A de Serotonina/genética , Glutationa , Dissulfeto de Glutationa , Antagonistas da Serotonina , Ligases
9.
Proc Natl Acad Sci U S A ; 116(49): 24796-24807, 2019 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-31727842

RESUMO

Brain infection by the parasite Toxoplasma gondii in mice is thought to generate vulnerability to predation by mechanisms that remain elusive. Monocytes play a key role in host defense and inflammation and are critical for controlling T. gondii However, the dynamic and regional relationship between brain-infiltrating monocytes and parasites is unknown. We report the mobilization of inflammatory (CCR2+Ly6Chi) and patrolling (CX3CR1+Ly6Clo) monocytes into the blood and brain during T. gondii infection of C57BL/6J and CCR2RFP/+CX3CR1GFP/+ mice. Longitudinal analysis of mice using 2-photon intravital imaging of the brain through cranial windows revealed that CCR2-RFP monocytes were recruited to the blood-brain barrier (BBB) within 2 wk of T. gondii infection, exhibited distinct rolling and crawling behavior, and accumulated within the vessel lumen before entering the parenchyma. Optical clearing of intact T. gondii-infected brains using iDISCO+ and light-sheet microscopy enabled global 3D detection of monocytes. Clusters of T. gondii and individual monocytes across the brain were identified using an automated cell segmentation pipeline, and monocytes were found to be significantly correlated with sites of T. gondii clusters. Computational alignment of brains to the Allen annotated reference atlas [E. S. Lein et al., Nature 445:168-176 (2007)] indicated a consistent pattern of monocyte infiltration during T. gondii infection to the olfactory tubercle, in contrast to LPS treatment of mice, which resulted in a diffuse distribution of monocytes across multiple brain regions. These data provide insights into the dynamics of monocyte recruitment to the BBB and the highly regionalized localization of monocytes in the brain during T. gondii CNS infection.


Assuntos
Barreira Hematoencefálica/metabolismo , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Monócitos/metabolismo , Toxoplasmose/diagnóstico por imagem , Toxoplasmose/metabolismo , Animais , Antígenos Ly/metabolismo , Barreira Hematoencefálica/diagnóstico por imagem , Receptor 1 de Quimiocina CX3C/metabolismo , Modelos Animais de Doenças , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Receptores CCR2/metabolismo
10.
Sensors (Basel) ; 22(22)2022 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-36433233

RESUMO

A novel diagnosis method based on the rotor slip is proposed in the paper to correctly detect current and speed sensor failures during the induction motor drive (IMD) operation. In order to enhance reliability and avoid confusion in the diagnosis algorithm due to the influence of measured signal quality, each fault type is determined in a priority order defined by the diagnosis method. Based on the features of the IMD applying the field-oriented control (FOC) technique, an innovative model uses the measured currents and reference speed as the input signals to estimate the rotor slip for the current sensor fault detection. After verifying the quality of the feedback of the current signals, a speed sensor fault function is continued, and performs according to relations among the reference speed, estimated speed based on the sliding mode method, and measured rotor speeds. Finally, the estimated quantities are selected to replace the wrong measured current or speed signals. The feasibility of the proposed approach is verified by simulations using Matlab-Simulink software as well as by practical experiments using an IMD prototype with a rated power of 2.2 kW and a DSC-TMS320F28335-based control system. The obtained simulation and experimental results demonstrated the feasibility, effectiveness, and reliability of the proposed diagnosis technique in detecting sensor failures and maintaining the stable operation of the IMD.


Assuntos
Reprodutibilidade dos Testes , Simulação por Computador
11.
J Vasc Surg ; 74(5): 1581-1587, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34022381

RESUMO

OBJECTIVE: Vascular surgeons are often called to aid other surgical specialties for complex exposure, hemorrhage control, or revascularization. The evolving role of the vascular surgeon in the management of intraoperative emergencies involving trauma patients remains undefined. The primary aims of this study included determining the prevalence of intraoperative vascular consultation in trauma, describing how these interactions have changed over time, and characterizing the outcomes achieved by vascular surgeons in these settings. We hypothesized that growing endovascular capabilities of vascular surgeons have resulted in an increased involvement of vascular surgery faculty in the management of the trauma patient over time. METHODS: A retrospective review of all operative cases at a single level I trauma center where a vascular surgeon was involved, but not listed as the primary surgeon, between 2002 and 2017 was performed. Cases were abstracted using Horizon Surgical Manager, a documentation system used in our operating room to track staff present, the type of case, and use. All elective cases were excluded. RESULTS: Of the 256 patients initially identified, 22 were excluded owing to the elective or joint nature of the procedure, leaving 234 emergent operative vascular consultations. Over the 15-year study period, a 529% increase in the number of vascular surgery consultations was seen, with 65% (n = 152) being intraoperative consultations requiring an immediate response. Trauma surgery (n = 103 [44%]) and orthopedic surgery (n = 94 [40%]) were the most common consulting specialties, with both demonstrating a trend of increasing consultations over time (general surgery, 1400%; orthopedic surgery, 220%). Indications for consultation were extremity malperfusion, hemorrhage, and concern for arterial injury. The average operative time for the vascular component of the procedures was 2.4 hours. Of patients presenting with ischemia, revascularization was successful in 94% (n = 116). Hemorrhage was controlled in 99% (n = 122). In-hospital mortality was relatively low at 7% (n = 17). Overall, despite the increase in intraoperative vascular consultations over time, a concomitant increase in the proportion of procedures done using endovascular techniques was not seen. CONCLUSIONS: Vascular surgeons are essential team members at a level I trauma center. Vascular consultation in this setting is often unplanned and often requires immediate intervention. The number of intraoperative vascular consultations is increasing and cannot be attributed solely to an increase in endovascular hemorrhage control, and instead may reflect the declining experience of trauma surgeons with vascular trauma. When consulted, vascular surgeons are effective in quickly gaining control of the situation to provide exposure, hemorrhage control, or revascularization.


Assuntos
Cuidados Intraoperatórios/tendências , Encaminhamento e Consulta/tendências , Cirurgiões/tendências , Centros de Traumatologia/tendências , Procedimentos Cirúrgicos Vasculares/tendências , Adulto , Feminino , Hemorragia/cirurgia , Técnicas Hemostáticas/tendências , Humanos , Masculino , Procedimentos Ortopédicos/tendências , Equipe de Assistência ao Paciente/tendências , Papel do Médico , Estudos Retrospectivos , Fatores de Tempo , Estados Unidos , Lesões do Sistema Vascular/cirurgia
12.
Pediatr Diabetes ; 22(3): 425-433, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33470492

RESUMO

AIM: We aimed to characterize associations between diet and the gut microbiome and short chain fatty acid (SCFA) products in youth with islet autoimmunity or type 1 diabetes (IA/T1D) in comparison with controls. RESEARCH DESIGN AND METHODS: Eighty participants (25 diagnosed with T1D, 17 with confirmed IA, 38 sibling or unrelated controls) from the Australian T1D Gut Study cohort were studied (median [IQR] age 11.7 [8.9, 14.0] years, 43% female). A Food Frequency Questionnaire characterized daily macronutrient intake over the preceding 6 months. Plasma and fecal SCFA were measured by gas chromatography; gut microbiome composition and diversity by 16S rRNA gene sequencing. RESULTS: A 10 g increase in daily carbohydrate intake associated with higher plasma acetate in IA/T1D (adjusted estimate +5.2 (95% CI 1.1, 9.2) µmol/L p = 0.01) and controls (adjusted estimate +4.1 [95% CI 1.7, 8.5] µmol/L p = 0.04). A 5 g increase in total fat intake associated with lower plasma acetate in IA/T1D and controls. A 5% increase in noncore (junk) food intake associated with reduced richness (adjusted estimate -4.09 [95%CI -7.83, -0.35] p = .03) and evenness (-1.25 [95% CI -2.00, -0.49] p < 0.01) of the gut microbiome in IA/T1D. Fiber intake associated with community structure of the microbiome in IA/T1D. CONCLUSIONS: Modest increments in carbohydrate and fat intake associated with plasma acetate in all youth. Increased junk food intake associated with reduced diversity of the gut microbiome in IA/T1D alone. These associations with the gut microbiome in IA/T1D support future efforts to promote SCFA by using dietary interventions.


Assuntos
Autoimunidade/fisiologia , Diabetes Mellitus Tipo 1/metabolismo , Dieta , Ácidos Graxos Voláteis/metabolismo , Microbioma Gastrointestinal , Ilhotas Pancreáticas/imunologia , Adolescente , Estudos de Casos e Controles , Criança , Estudos Transversais , Diabetes Mellitus Tipo 1/complicações , Feminino , Humanos , Masculino , Inquéritos e Questionários
13.
J Med Internet Res ; 22(11): e22894, 2020 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-33122164

RESUMO

BACKGROUND: The COVID-19 pandemic has imposed a heavy burden on health care systems and governments. Health literacy (HL) and eHealth literacy (as measured by the eHealth Literacy Scale [eHEALS]) are recognized as strategic public health elements but they have been underestimated during the pandemic. HL, eHEALS score, practices, lifestyles, and the health status of health care workers (HCWs) play crucial roles in containing the COVID-19 pandemic. OBJECTIVE: The aim of this study is to evaluate the psychometric properties of the eHEALS and examine associations of HL and eHEALS scores with adherence to infection prevention and control (IPC) procedures, lifestyle changes, and suspected COVID-19 symptoms among HCWs during lockdown. METHODS: We conducted an online survey of 5209 HCWs from 15 hospitals and health centers across Vietnam from April 6 to April 19, 2020. Participants answered questions related to sociodemographics, HL, eHEALS, adherence to IPC procedures, behavior changes in eating, smoking, drinking, and physical activity, and suspected COVID-19 symptoms. Principal component analysis, correlation analysis, and bivariate and multivariate linear and logistic regression models were used to validate the eHEALS and examine associations. RESULTS: The eHEALS had a satisfactory construct validity with 8 items highly loaded on one component, with factor loadings ranked from 0.78 to 0.92 explaining 76.34% of variance; satisfactory criterion validity as correlated with HL (ρ=0.42); satisfactory convergent validity with high item-scale correlations (ρ=0.80-0.84); and high internal consistency (Cronbach α=.95). HL and eHEALS scores were significantly higher in men (unstandardized coefficient [B]=1.01, 95% CI 0.57-1.45, P<.001; B=0.72, 95% CI 0.43-1.00, P<.001), those with a better ability to pay for medication (B=1.65, 95% CI 1.25-2.05, P<.001; B=0.60, 95% CI 0.34-0.86, P<.001), doctors (B=1.29, 95% CI 0.73-1.84, P<.001; B 0.56, 95% CI 0.20-0.93, P=.003), and those with epidemic containment experience (B=1.96, 95% CI 1.56-2.37, P<.001; B=0.64, 95% CI 0.38-0.91, P<.001), as compared to their counterparts, respectively. HCWs with higher HL or eHEALS scores had better adherence to IPC procedures (B=0.13, 95% CI 0.10-0.15, P<.001; B=0.22, 95% CI 0.19-0.26, P<.001), had a higher likelihood of healthy eating (odds ratio [OR] 1.04, 95% CI 1.01-1.06, P=.001; OR 1.04, 95% CI 1.02-1.07, P=.002), were more physically active (OR 1.03, 95% CI 1.02-1.03, P<.001; OR 1.04, 95% CI 1.03-1.05, P<.001), and had a lower likelihood of suspected COVID-19 symptoms (OR 0.97, 95% CI 0.96-0.98, P<.001; OR 0.96, 95% CI 0.95-0.98, P<.001), respectively. CONCLUSIONS: The eHEALS is a valid and reliable survey tool. Gender, ability to pay for medication, profession, and epidemic containment experience were independent predictors of HL and eHEALS scores. HCWs with higher HL or eHEALS scores had better adherence to IPC procedures, healthier lifestyles, and a lower likelihood of suspected COVID-19 symptoms. Efforts to improve HCWs' HL and eHEALS scores can help to contain the COVID-19 pandemic and minimize its consequences.


Assuntos
COVID-19/epidemiologia , Letramento em Saúde/métodos , Pessoal de Saúde/normas , Psicometria/métodos , SARS-CoV-2/patogenicidade , Telemedicina/métodos , Adulto , COVID-19/prevenção & controle , Feminino , Humanos , Estilo de Vida , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Inquéritos e Questionários , Adulto Jovem
14.
BMC Plant Biol ; 19(1): 262, 2019 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-31208336

RESUMO

BACKGROUND: Stored potato (Solanum tuberosum L.) tubers are sensitive to wet conditions that can cause rotting in long-term storage. To study the effect of water on the tuber surface during storage, microarray analysis, RNA-Seq profiling, qRT-PCR and phytohormone measurements were performed to study gene expression and hormone content in wet tubers incubated at two temperatures: 4 °C and 15 °C. The growth of the plants was also observed in a greenhouse after the incubation of tubers in wet conditions. RESULTS: Wet conditions induced a low-oxygen response, suggesting reduced oxygen availability in wet tubers at both temperatures when compared to that in the corresponding dry samples. Wet conditions induced genes coding for heat shock proteins, as well as proteins involved in fermentative energy production and defense against reactive oxygen species (ROS), which are transcripts that have been previously associated with low-oxygen stress in hypoxic or anoxic conditions. Wet treatment also induced senescence-related gene expression and genes involved in cell wall loosening, but downregulated genes encoding protease inhibitors and proteins involved in chloroplast functions and in the biosynthesis of secondary metabolites. Many genes involved in the production of phytohormones and signaling were also affected by wet conditions, suggesting altered regulation of growth by wet conditions. Hormone measurements after incubation showed increased salicylic acid (SA), abscisic acid (ABA) and auxin (IAA) concentrations as well as reduced production of jasmonate 12-oxo-phytodienoic acid (OPDA) in wet tubers. After incubation in wet conditions, the tubers produced fewer stems and more roots compared to controls incubated in dry conditions. CONCLUSIONS: In wet conditions, tubers invest in ROS protection and defense against the abiotic stress caused by reduced oxygen due to excessive water. Changes in ABA, SA and IAA that are antagonistic to jasmonates affect growth and defenses, causing induction of root growth and rendering tubers susceptible to necrotrophic pathogens. Water on the tuber surface may function as a signal for growth, similar to germination of seeds.


Assuntos
Armazenamento de Alimentos , Reguladores de Crescimento de Plantas/metabolismo , Tubérculos/metabolismo , Solanum tuberosum/metabolismo , Metabolismo dos Carboidratos , Parede Celular/metabolismo , Cloroplastos/metabolismo , Regulação da Expressão Gênica de Plantas , Análise de Sequência com Séries de Oligonucleotídeos , Estresse Oxidativo , Tubérculos/crescimento & desenvolvimento , Metabolismo Secundário , Solanum tuberosum/crescimento & desenvolvimento , Transcriptoma , Água
15.
Pediatr Diabetes ; 20(5): 574-583, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31081243

RESUMO

AIMS/HYPOTHESIS: To investigate the longitudinal relationship between the gut microbiome, circulating short chain fatty acids (SCFAs) and intestinal permeability in children with islet autoimmunity or type 1 diabetes and controls. METHODS: We analyzed the gut bacterial microbiome, plasma SCFAs, small intestinal permeability and dietary intake in 47 children with islet autoimmunity or recent-onset type 1 diabetes and in 41 unrelated or sibling controls over a median (range) of 13 (2-34) months follow-up. RESULTS: Children with multiple islet autoantibodies (≥2 IA) or type 1 diabetes had gut microbiome dysbiosis. Anti-inflammatory Prevotella and Butyricimonas genera were less abundant and these changes were not explained by differences in diet. Small intestinal permeability measured by blood lactulose:rhamnose ratio was higher in type 1 diabetes. Children with ≥2 IA who progressed to type 1 diabetes (progressors), compared to those who did not progress, had higher intestinal permeability (mean [SE] difference +5.14 [2.0], 95% confidence interval [CI] 1.21, 9.07, P = .006), lower within-sample (alpha) microbial diversity (31.3 [11.2], 95% CI 9.3, 53.3, P = .005), and lower abundance of SCFA-producing bacteria. Alpha diversity (observed richness) correlated with plasma acetate levels in all groups combined (regression coefficient [SE] 0.57 [0.21], 95% CI 0.15, 0.99 P = .008). CONCLUSIONS/INTERPRETATION: Children with ≥2 IA who progress to diabetes, like those with recent-onset diabetes, have gut microbiome dysbiosis associated with increased intestinal permeability. Interventions that expand gut microbial diversity, in particular SCFA-producing bacteria, may have a role to decrease progression to diabetes in children at-risk.


Assuntos
Diabetes Mellitus Tipo 1/microbiologia , Disbiose/imunologia , Ácidos Graxos Voláteis/sangue , Microbioma Gastrointestinal , Mucosa Intestinal/metabolismo , Adolescente , Autoimunidade , Criança , Pré-Escolar , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/imunologia , Feminino , Humanos , Ilhotas Pancreáticas/imunologia , Masculino , Permeabilidade , Estudos Prospectivos
16.
J Clin Periodontol ; 46(2): 197-205, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30578564

RESUMO

INTRODUCTION: Periodontal diseases (PD) are complex oral inflammatory diseases initiated by keystone bacteria such as Porphyromonas gingivalis. A vaccine for PD is desirable as clinical treatment involves protracted maintenance strategies aimed to retain dentition. Although prior immunization approaches targeting P. gingivalis have reported variable success in limiting facets of disease such as oral bone loss, it remains that a vaccine for this disease may be attainable. AIM: To investigate cell-free protein synthesis (CFPS) as a platform to produce vaccinable targets suitable for efficacy testing in a P. gingivalis-induced murine oral bone loss model. MATERIALS AND METHODS: Recombinantly generated P. gingivalis minor fimbriae protein (Mfa1), RgpA gingipain hemagglutinin domain 1 (HA1), and RgpA gingipain hemagglutinin domain 2 (HA2) were combined in equivalent doses in adjuvants and injected intramuscularly to immunize mice. Serum levels of protein-specific antibody were measured by ELISA, and oral bone levels were defined by morphometrics. RESULTS: Recombinantly generated P. gingivalis proteins possessed high fidelity to predicted size and elicited protein-specific IgG following immunization. Importantly, immunization with the vaccine cocktail protected from P. gingivalis elicited oral bone loss. CONCLUSION: These data verify the utility of the CFPS technology to synthesize proteins that have the capacity to serve as novel vaccines.


Assuntos
Perda do Osso Alveolar , Infecções por Bacteroidaceae , Adesinas Bacterianas , Animais , Anticorpos Antibacterianos , Vacinas Bacterianas , Cisteína Endopeptidases , Imunização , Camundongos , Camundongos Endogâmicos BALB C , Porphyromonas gingivalis
17.
Biochemistry ; 57(5): 516-519, 2018 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-29323879

RESUMO

Malaria, one of the most common vector borne human diseases, is a major world health issue. In 2015 alone, more than 200 million people were infected with malaria, out of which, 429 000 died. Even though artemisinin-based combination therapies (ACT) are highly effective at treating malaria infections, novel efforts toward development of vaccines to prevent transmission are still needed. Pfs25, a postfertilization stage parasite surface antigen, is a leading transmission-blocking vaccine (TBV) candidate. It is postulated that Pfs25 anchors to the cell membrane using a glycosylphosphatidylinositol (GPI) linker, which itself possesses pro-inflammatory properties. In this study, Escherichia coli derived extract (XtractCF+TM) was used in cell free protein synthesis [CFPS] to successfully express >200 mg/L of recombinant Pfs25 with a C-terminal non-natural amino acid (nnAA), namely, p-azidomethyl phenylalanine (pAMF), which possesses a reactive azide group. Thereafter, a unique conjugate vaccine (CV), namely, Pfs25-GPI was generated with dibenzocyclooctyne (DBCO) derivatized glycan core of malaria GPI using a simple but highly efficient copper free click chemistry reaction. In mice immunized with Pfs25 or Pfs25-GPI, the Pfs25-GPI group showed significantly higher titers compared to the Pfs25 group. Moreover, only purified IgGs from Pfs25-GPI group were able to significantly block transmission of parasites to mosquitoes, as judged by a standard membrane feeding assay [SMFA]. To our knowledge, this is the first report of the generation of a CV using Pfs25 and malaria specific GPI where the GPI is shown to enhance the ability of Pfs25 to elicit transmission blocking antibodies.


Assuntos
Glicosilfosfatidilinositóis/uso terapêutico , Vacinas Antimaláricas/uso terapêutico , Malária Falciparum/prevenção & controle , Plasmodium falciparum/imunologia , Proteínas de Protozoários/uso terapêutico , Animais , Formação de Anticorpos , Glicosilfosfatidilinositóis/imunologia , Humanos , Imunização , Malária , Vacinas Antimaláricas/imunologia , Malária Falciparum/imunologia , Malária Falciparum/transmissão , Camundongos , Proteínas de Protozoários/imunologia , Vacinas Conjugadas/imunologia , Vacinas Conjugadas/uso terapêutico , Vacinas Sintéticas/imunologia , Vacinas Sintéticas/uso terapêutico
18.
Environ Geochem Health ; 39(3): 517-529, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27149867

RESUMO

The contamination characteristics of arsenic and other trace elements in groundwater and the potential risks of arsenic from the groundwater were investigated. Elevated contamination of arsenic, barium and manganese was observed in tube-well water of two villages (Chuyen Ngoai and Chau Giang) in Ha Nam province in the Northern Vietnam. Concentrations of As in the groundwater ranged from 12.8 to 884 µg/L with mean values in Chuyen Ngoai and Chau Giang were 614.7 and 160.1 µg/L, respectively. About 83 % of these samples contained As concentrations exceeding WHO drinking water guideline of 10 µg/L. The mean values of Mn and Ba in groundwater from Chuyen Ngoai and Chau Giang were 300 and 657 µg/L and 650 and 468 µg/L, respectively. The mean value of Ba concentration in groundwater in both Chuyen Ngoai and Chau Giang was about 22 % of the samples exceeded the WHO guideline (700 µg/L). Arsenic concentrations in human urine of residents from Chuyen Ngoai and Chau Giang were the range from 8.6 to 458 µg/L. The mean values of Mn and Ba in human urine of local people from Chuyen Ngoai were 46.9 and 62.8 µg/L, respectively, while those in people from Chau Giang were 25.9 and 45.9 µg/L, respectively. The average daily dose from ingesting arsenic for consuming both untreated and treated groundwater is from 0.02 to 11.5 and 0.003 to 1.6 µg/kg day, respectively. Approximately, 57 % of the families using treated groundwater and 64 % of the families using untreated groundwater could be affected by elevated arsenic exposure.


Assuntos
Arsênio/análise , Bário/análise , Água Subterrânea/química , Manganês/análise , Poluentes Químicos da Água/análise , Água Potável/análise , Água Potável/química , Humanos , Medição de Risco , Oligoelementos/análise , Vietnã
19.
Crit Rev Microbiol ; 41(3): 326-40, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-24645635

RESUMO

The capacity of our gut microbial communities to maintain a stable and balanced state, termed 'resilience', in spite of perturbations is vital to our achieving and maintaining optimal health. A loss of microbial resilience is observed in a number of diseases including obesity, diabetes and metabolic syndrome. There are large gaps in our understanding of why an individual's co-evolved microflora consortium fail to develop resilience thereby establishing a trajectory towards poor metabolic health. This review examines the connections between the developing gut microbiota and intestinal barrier function in the neonate, infant and during the first years of life. We propose that the effects of early life events on the gut microflora and permeability, whilst it is in a dynamic and vulnerable state, are fundamental in shaping the microbial consortia's resilience and that it is the maintenance of resilience that is pivotal for metabolic health throughout life. We review the literature supporting this concept suggesting new potential research directions aimed at developing a greater understanding of the longitudinal effects of the gut microflora on metabolic health and potential interventions to recalibrate the 'at risk' infant gut microflora in the direction of enhanced metabolic health.


Assuntos
Microbioma Gastrointestinal/fisiologia , Trato Gastrointestinal/microbiologia , Mucosa Intestinal/microbiologia , Consórcios Microbianos/fisiologia , Permeabilidade , Fatores Etários , Anti-Infecciosos/farmacologia , Feminino , Humanos , Lactente , Recém-Nascido , Mucosa Intestinal/imunologia , Gravidez , Junções Íntimas/fisiologia
20.
Altern Ther Health Med ; 21 Suppl 2: 22-31, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26308757

RESUMO

CONTEXT: Chemotherapeutic agents such as methotrexate (MTX) are commonly used in the treatment of cancer. MTX is an antimetabolite and antifolate drug that targets folate production in rapidly dividing intestinal cells during deoxyribonucleic acid/ribonucleic acid (DNA/RNA) synthesis, thus indiscriminately diminishing enterocyte numbers and disrupting brush-border enzyme activities. The resultant damage leads to a debilitating condition known as intestinal mucositis. New treatment strategies need to be developed for mucositis, as currently no effective treatment exists. OBJECTIVES: The efficacy of zinc in combination with the probiotic Streptococcus salivarius subsp thermophilus (TH-4) to ameliorate MTX-induced mucositis was investigated. DESIGN: C57BL/6 mice were randomly assigned to 5 groups: (1) negative control group-saline + saline (SS group); (2) MTX-treated control group-saline + MTX (SM group); (3) MTX-treated intervention group-zinc + TH-4 probiotic + MTX (ZPM group); (4) MTX-treated intervention group-zinc + MTX (ZM group); and (5) MTX-treated intervention group-TH-4 probiotic + MTX (PM group). The mice were gavaged daily from days 1-16 with their respective treatments. From days 6-8, a total of 3 consecutive, daily subcutaneous injections of MTX were used to induce mucositis in the 4 MTX-treated intervention groups, with saline used for the negative controls. SETTING: The study was conducted in the gastroenterology unit at the Women's and Children's Health Network, North Adelaide, SA, Australia. OUTCOME MEASURES: Mice were sacrificed on days 10, 13, and 16. Measurements included body weight, the disease activity index, small-intestine (SI) length and weight, villus height, crypt depth, and mucosal thickness. Also, gut tissues were collected for histological assessments, evaluation of myeloperoxidase (MPO) activity, and analysis of metallothionein (MT) levels. RESULTS: On days 10 and 13, the treatments received by the ZPM and ZM groups resulted in significantly less jejunal damage (P < .05) compared with the MTX-treated controls (SM) and the PM groups. Zinc treatments in the ZM group induced a 3-fold increase in MT levels, resulting in a significant difference between that group and the SM group (P < .001). The treatments also led to MPO activity that was 31% lower on day 10 compared with the SM and PM groups (P < .01 for each comparison). Mice in the ZM and the ZPM groups showed increased villus height (P < .05) on day 10 compared with the SM and PM groups. Similarly, mucosal thickness was significantly greater in the ZPM and ZM groups on day 10 compared with the SM and PM groups, by 36% (P = .014) and 34% (P = .002), respectively. On day 16, after treatment with zinc in the ZM and ZPM groups, SI weight was 24% lower for the ZM group and 26% lower for the ZPM group compared with the SM group (both P < .001). Crypt depth was increased in the PM group at day 10, resulting in a crypt depth that was 30% greater than that of the SM group (P = .002). CONCLUSION: Zinc supplementation alone may be an effective treatment strategy for MTX-induced mucositis, possibly by inducing MT directly.


Assuntos
Mucosa Intestinal/efeitos dos fármacos , Intestino Delgado/efeitos dos fármacos , Metotrexato/toxicidade , Mucosite/induzido quimicamente , Mucosite/tratamento farmacológico , Zinco/farmacologia , Animais , Peso Corporal/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Intestino Delgado/metabolismo , Intestino Delgado/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Mucosite/patologia , Probióticos/farmacologia
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