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1.
J Infect Dis ; 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38169323

RESUMO

BACKGROUND: Tuberculous meningitis (TBM) is difficult to diagnose. We investigated whether a 3-gene host response signature in blood can distinguish TBM from other brain infections. METHODS: The expression of 3 genes (Dual specificity phosphatase 3- DUSP3, Guanylate-binding protein- GBP5, Krupple-like factor 2- KLF2) was analysed by RNA sequencing of archived whole blood from four cohorts of Vietnamese adults: 281 with TBM; 279 with pulmonary tuberculosis; 50 with other brain infections; and 30 healthy controls. 'TB scores' (combined 3-gene expression) were calculated following published methodology and discriminatory performance compared using area under a receiver operator characteristic curve (AUC). RESULTS: GBP5 was upregulated in TBM compared to other brain infections (p < 0.001), with no difference in DUSP3 and KLF2 expression. The diagnostic performance of GBP5 alone (AUC 0.74 (95% CI 0.67-0.81)) was slightly better than the 3-gene TB score (AUC 0.66, 95% CI 0.58-0.73) in TBM. Both GBP5 expression and TB score were higher in HIV-positive participants (P < 0.001), with good diagnostic performance of GBP5 alone (AUC 0.86, 95% CI 0.80-0.93). CONCLUSION: The 3-gene host signature in whole blood has the ability to discriminate TBM from other brain infections, including in HIV-positive individuals. Validation in large prospective diagnostic study is now required.

2.
Inorg Chem ; 63(6): 2909-2918, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38301278

RESUMO

We here report the synthesis of the homoleptic iron(II) N-heterocyclic carbene (NHC) complex [Fe(miHpbmi)2](PF6)4 (miHpbmi = 4-((3-methyl-1H-imidazolium-1-yl)pyridine-2,6-diyl)bis(3-methylimidazol-2-ylidene)) and its electrochemical and photophysical properties. The introduction of the π-electron-withdrawing 3-methyl-1H-imidazol-3-ium-1-yl group into the NHC ligand framework resulted in stabilization of the metal-to-ligand charge transfer (MLCT) state and destabilization of the metal-centered (MC) states. This resulted in an improved excited-state lifetime of 16 ps compared to the 9 ps for the unsubstituted parent compound [Fe(pbmi)2](PF6)2 (pbmi = (pyridine-2,6-diyl)bis(3-methylimidazol-2-ylidene)) as well as a stronger MLCT absorption band extending more toward the red spectral region. However, compared to the carboxylic acid derivative [Fe(cpbmi)2](PF6)2 (cpbmi = 1,1'-(4-carboxypyridine-2,6-diyl)bis(3-methylimidazol-2-ylidene)), the excited-state lifetime of [Fe(miHpbmi)2](PF6)4 is the same, but both the extinction and the red shift are more pronounced for the former. Hence, this makes [Fe(miHpbmi)2](PF6)4 a promising pH-insensitive analogue of [Fe(cpbmi)2](PF6)2. Finally, the excited-state dynamics of the title compound [Fe(miHpbmi)2](PF6)4 was investigated in solvents with different viscosities, however, showing very little dependency of the depopulation of the excited states on the properties of the solvent used.

3.
Inorg Chem ; 63(10): 4461-4473, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38421802

RESUMO

Two iron complexes featuring the bidentate, nonconjugated N-heterocyclic carbene (NHC) 1,1'-methylenebis(3-methylimidazol-2-ylidene) (mbmi) ligand, where the two NHC moieties are separated by a methylene bridge, have been synthesized to exploit the combined influence of geometric and electronic effects on the ground- and excited-state properties of homoleptic FeIII-hexa-NHC [Fe(mbmi)3](PF6)3 and heteroleptic FeII-tetra-NHC [Fe(mbmi)2(bpy)](PF6)2 (bpy = 2,2'-bipyridine) complexes. They are compared to the reported FeIII-hexa-NHC [Fe(btz)3](PF6)3 and FeII-tetra-NHC [Fe(btz)2(bpy)](PF6)2 complexes containing the conjugated, bidentate mesoionic NHC ligand 3,3'-dimethyl-1,1'-bis(p-tolyl)-4,4'-bis(1,2,3-triazol-5-ylidene) (btz). The observed geometries of [Fe(mbmi)3](PF6)3 and [Fe(mbmi)2(bpy)](PF6)2 are evaluated through L-Fe-L bond angles and ligand planarity and compared to those of [Fe(btz)3](PF6)3 and [Fe(btz)2(bpy)](PF6)2. The FeII/FeIII redox couples of [Fe(mbmi)3](PF6)3 (-0.38 V) and [Fe(mbmi)2(bpy)](PF6)2 (-0.057 V, both vs Fc+/0) are less reducing than [Fe(btz)3](PF6)3 and [Fe(btz)2(bpy)](PF6)2. The two complexes show intense absorption bands in the visible region: [Fe(mbmi)3](PF6)3 at 502 nm (ligand-to-metal charge transfer, 2LMCT) and [Fe(mbmi)2(bpy)](PF6)2 at 410 and 616 nm (metal-to-ligand charge transfer, 3MLCT). Lifetimes of 57.3 ps (2LMCT) for [Fe(mbmi)3](PF6)3 and 7.6 ps (3MLCT) for [Fe(mbmi)2(bpy)](PF6)2 were probed and are somewhat shorter than those for [Fe(btz)3](PF6)3 and [Fe(btz)2(bpy)](PF6)2. [Fe(mbmi)3](PF6)3 exhibits photoluminescence at 686 nm (2LMCT) in acetonitrile at room temperature with a quantum yield of (1.2 ± 0.1) × 10-4, compared to (3 ± 0.5) × 10-4 for [Fe(btz)3](PF6)3.

4.
Sleep Breath ; 27(4): 1629-1637, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36434377

RESUMO

PURPOSE: This study aimed to determine the prevalence of post-stroke depression (PSD) during the first year and its associated factors, especially focusing on sleep quality and fatigue severity. METHODS: A cross-sectional study was conducted among stroke patients in Vietnam's National Geriatric Hospital. Data were collected by using standardized questionnaires for interviewing and evaluating patients at the research site. Several covariables were presented including demographics, stroke-related characteristics, activities of daily living, post-stroke fatigue, and sleep quality (Pittsburgh Sleep Quality Index [PSQI] scale). PSD was assessed as an outcome variable through the Patient Health Questionnaire-9 scale. To summarize sociodemographic and clinical variables, descriptive statistics were performed. A logistic regression model was used to explore the factors related to PSD. RESULTS: Of 157 patients with stroke, mean age 73.1 (± 9.6), PSD was present in 60 patients (38%). The global score and all PSQI components of participants with PSD showed worse levels than those without depression. Furthermore, the prevalence of PSD was higher in patients with low IADL scores and functional disability at high levels. In the multivariate logistic regression analysis, the patients with PSD showed higher Fatigue Severity Scale (FSS) scores (OR = 4.11; 95% CI = 1.39; 12.19) and higher scores in two domains of the PSQI scale including subjective sleep quality (OR = 3.03; 95% CI = 1.21; 7.58) and sleep disturbance (OR = 5.22; 95% CI = 1.33; 20.47). CONCLUSION: There is a significant prevalence of depression following stroke. Furthermore, post-stroke fatigue and two PSQI scale components (subjective sleep quality and sleep disturbance) were shown to be associated with PSD. This finding may guide early screening and intervention strategies to address depression following stroke.


Assuntos
Transtornos do Sono-Vigília , Acidente Vascular Cerebral , Idoso , Humanos , Atividades Cotidianas , Estudos Transversais , Depressão/diagnóstico , Depressão/epidemiologia , Fadiga/diagnóstico , Fadiga/epidemiologia , Fadiga/etiologia , Qualidade do Sono , Transtornos do Sono-Vigília/diagnóstico , Transtornos do Sono-Vigília/epidemiologia , Transtornos do Sono-Vigília/complicações , População do Sudeste Asiático , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/epidemiologia , Vietnã/epidemiologia , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais
5.
Plant Cell Physiol ; 63(4): 550-564, 2022 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-35139224

RESUMO

In barley, incubation of primary dormant (D1) grains on water under conditions that do not allow germination, i.e. 30°C in air and 15°C or 30°C in 5% O2, induces a secondary dormancy (D2) expressed as a loss of the ability to germinate at 15°C in air. The aim of this study was to compare the proteome of barley embryos isolated from D1 grains and D2 ones after induction of D2 at 30°C or in hypoxia at 15°C or 30°C. Total soluble proteins were analyzed by 2DE gel-based proteomics, allowing the selection of 130 differentially accumulated proteins (DAPs) among 1,575 detected spots. According to the protein abundance profiles, the DAPs were grouped into six abundance-based similarity clusters. Induction of D2 is mainly characterized by a down-accumulation of proteins belonging to cluster 3 (storage proteins, proteases, alpha-amylase inhibitors and histone deacetylase HD2) and an up-accumulation of proteins belonging to cluster 4 (1-Cys peroxiredoxin, lipoxygenase2 and caleosin). The correlation-based network analysis for each cluster highlighted central protein hub. In addition, most of genes encoding DAPs display high co-expression degree with 19 transcription factors. Finally, this work points out that similar molecular events accompany the modulation of dormancy cycling by both temperature and oxygen, including post-translational, transcriptional and epigenetic regulation.


Assuntos
Hordeum , Ácido Abscísico/metabolismo , Epigênese Genética , Germinação , Hordeum/metabolismo , Hipóxia/genética , Hipóxia/metabolismo , Oxigênio/metabolismo , Dormência de Plantas/fisiologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Proteômica , Sementes/metabolismo , Temperatura
6.
Small ; 18(34): e2202963, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35908157

RESUMO

With its superior theoretical energy density as well as abundance and environment-friendliness, the lithium-sulfur battery (LiSB) is a potential candidate to replace the traditional energy storage and generation systems. An innovative design is proposed for the high-performance solid-state LiSB system by combining the multi-functional cathode comprising the sulfur-loaded Al2 O3 -modified carbon nanotubes (S@ACNTs) and the flexible hybrid solid electrolyte (HSE). Assembled with S@ACNTs active material, the polycation poly(diallyldimethylammonium bis(trifluoromethylsulfonyl)imide) (PDATFSI) binder exhibits high Li+ conductivity of 0.45 mS cm-1 at room temperature, good thermal stability up to 450 °C, high adhesive strength with aluminum current collector up to 24 MPa, sustainable non-flammability, and desirable flexibility. When assembled with HSE membrane, the S@ACNTs/PDATFSI-60IL cathode layer demonstrates effective polysulfide trapping behavior and superior compatibility (65 Ω), resulting in high discharge capacity of 1203 mAh g-1 at 0.2 C in the 1st cycle, and long-term stability up to 91.69% of the discharge capacity after 200 cycles of charge/discharge process.

7.
Arch Virol ; 167(4): 1131-1135, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35174413

RESUMO

African swine fever virus (ASF) has circulated in Vietnam since 2018, causing significant losses to the pig industry. Quick, accurate diagnosis of African swine fever virus (ASFV) infection is crucial for controlling the disease. The detection of the virus in piglets with congenital tremors is described in this paper. ASFV was detected in brain tissues by polymerase chain reaction (PCR) and immunohistochemistry. Classical swine fever virus, porcine parvovirus, porcine reproductive and respiratory syndrome virus, and pseudorabies virus were not detected by PCR, suggesting that the ASFV was the cause of these neurological signs.


Assuntos
Vírus da Febre Suína Africana , Febre Suína Africana , Vírus da Febre Suína Clássica , Vírus da Síndrome Respiratória e Reprodutiva Suína , Febre Suína Africana/diagnóstico , Vírus da Febre Suína Africana/genética , Animais , Suínos , Tremor
8.
Eur Phys J E Soft Matter ; 45(5): 42, 2022 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-35507140

RESUMO

The predictive capabilities of some existing theoretical models to quantify thermodiffusion have been investigated in this work. To do so, the tests have been performed on two model fluids, the hard-sphere and the Lennard-Jones (including spheres and dimers) ones, exploring different mixtures and thermodynamic conditions thanks to extensive molecular simulations. It has been confirmed that the thermal diffusion factor should be expressed as the sum of one term related to the isotope effect and one term related to the "chemical" effects and that a kinetic term is required to quantify thermodiffusion from the gas state to the liquid state. In addition, regarding the isotope effects, it has been obtained that none of the available theoretical models are able to yield a reasonable prediction relatively to the molecular simulations results and that the moment of inertia contribution is one order of magnitude smaller than the mass contribution in the liquid state. Finally, concerning the chemical effects, it has been shown the Shukla and Firoozabadi model, complemented with a kinetic term, is probably the most reasonable option to estimate the chemical contribution to the thermal diffusion factor, even if it fails in capturing the effect of the asymmetry in size and in shape between the species. Overall, this works confirms that there is still a lack of a generic model able to predict accurately thermal diffusion factors, or equivalently Soret coefficient, in simple binary mixtures from the gas state to the liquid state.

9.
Phys Chem Chem Phys ; 24(35): 21178-21187, 2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36039911

RESUMO

We present a new water-dependent molecular mechanism for the widely-used protein stabilizing osmolyte, trimethylamine N-oxide (TMAO), whose mode of action has remained controversial. Classical interpretations, such as osmolyte exclusion from the vicinity of protein, cannot adequately explain the behavior of this osmolyte and were challenged by recent data showing the direct interactions of TMAO with proteins, mainly via hydrophobic binding. Solvent effect theories also fail to propose a straightforward mechanism. To explore the role of water and the hydrophobic association, we disabled osmolyte-protein hydrophobic interactions by replacing water with hexane and using lipase enzyme as an anhydrous-stable protein. Biocatalysis experiments showed that under this non-aqueous condition, TMAO does not act as a stabilizer, but strongly deactivates the enzyme. Molecular dynamics (MD) simulations reveal that TMAO accumulates near the enzyme and makes many hydrogen bonds with it, like denaturing osmolytes. Some TMAO molecules even reach the active site and interact strongly with the catalystic traid. In aqueous solvent, the enzyme functions well: the extent of TMAO interactions is reduced and can be divided into both polar and non-polar terms. Structural analysis shows that in water, some TMAO molecules bind to the enzyme surface like a surfactant. We show that these interactions limit water-protein hydrogen bonds and unfavorable water-hydrophobic surface contacts. Moreover, a more hydrophobic environment is formed in the solvation layer, which reduces water dynamics and subsequently, rigidifies the backbone in aqueous solution. We show that osmolyte amphiphilicity and protein surface heterogeneity can address the weaknesses of exclusion and solvent effect theories about the TMAO mechanism.


Assuntos
Metilaminas , Proteínas , Interações Hidrofóbicas e Hidrofílicas , Metilaminas/química , Proteínas/química , Solventes/química , Ureia/química , Água/química
10.
Sensors (Basel) ; 22(2)2022 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-35062393

RESUMO

Cyber security has become increasingly challenging due to the proliferation of the Internet of things (IoT), where a massive number of tiny, smart devices push trillion bytes of data to the Internet. However, these devices possess various security flaws resulting from the lack of defense mechanisms and hardware security support, therefore making them vulnerable to cyber attacks. In addition, IoT gateways provide very limited security features to detect such threats, especially the absence of intrusion detection methods powered by deep learning. Indeed, deep learning models require high computational power that exceeds the capacity of these gateways. In this paper, we introduce Realguard, an DNN-based network intrusion detection system (NIDS) directly operated on local gateways to protect IoT devices within the network. The superiority of our proposal is that it can accurately detect multiple cyber attacks in real time with a small computational footprint. This is achieved by a lightweight feature extraction mechanism and an efficient attack detection model powered by deep neural networks. Our evaluations on practical datasets indicate that Realguard could detect ten types of attacks (e.g., port scan, Botnet, and FTP-Patator) in real time with an average accuracy of 99.57%, whereas the best of our competitors is 98.85%. Furthermore, our proposal effectively operates on resource-constraint gateways (Raspberry PI) at a high packet processing rate reported about 10.600 packets per second.


Assuntos
Internet das Coisas , Segurança Computacional , Computadores , Internet , Redes Neurais de Computação
11.
Epilepsia ; 62(2): 397-407, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33475161

RESUMO

OBJECTIVE: This study aimed to evaluate the proportion of patients with seizures and electroencephalography (EEG) abnormalities in autoimmune encephalitis (AE) and its most common subtypes. METHODS: This systematic review followed Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) standards and was registered with the International Prospective Register of Systematic Reviews (PROSPERO). We searched Medline All, Embase, and PsychINFO in Ovid from inception to June 2019 for articles pertaining to AE and seizure. Included studies reported seizure and/or EEG data in cohorts of ≥10 AE patients. Patient demographics, antibody type, seizure incidence, and EEG findings were extracted. Review of studies and data extraction were performed in duplicate. In addition to descriptive analysis, quantitative synthesis stratified by autoantibody subtype was performed with logistic regression and chi-square analyses. RESULTS: Our search yielded 3856 abstracts: 1616 were selected for full-text review and 118 studies met eligibility criteria. Of 3722 antibody-positive AE patients, 2601 (69.9%) had clinical seizures during the course of their illness. Of the 2025 patients with antibody-positive AE and available EEG data, 1718 (84.8%) had some EEG abnormality (eg, epileptiform discharges, slowing, and so on). Anti- N-methyl-d-aspartate (NMDA) receptor encephalitis (anti-NMDARE) was the most commonly reported type of AE (1985/3722, 53.3%). Of the anti-NMDARE patients with available seizure or EEG data, 71.8% (n = 1425/1985) had clinical seizures during their illness, and 89.7% (n = 1172/1306) had EEG abnormalities. For all AE patients and in the anti-NMDARE subpopulation, seizures were more common in younger patients (p < .05). SIGNIFICANCE: This systematic review provides an estimate of the proportion of AE patients with seizures, confirming the magnitude of seizure burden in this population. Prospective studies are needed to understand population-based prevalence of seizures, identify factors associated with seizures, and evaluate particular EEG findings as biomarkers of seizures and outcomes in AE.


Assuntos
Encefalite Antirreceptor de N-Metil-D-Aspartato/fisiopatologia , Encefalite/fisiopatologia , Doença de Hashimoto/fisiopatologia , Convulsões/fisiopatologia , Encefalite Antirreceptor de N-Metil-D-Aspartato/imunologia , Autoanticorpos/imunologia , Doenças Autoimunes do Sistema Nervoso/imunologia , Doenças Autoimunes do Sistema Nervoso/fisiopatologia , Eletroencefalografia , Encefalite/imunologia , Glutamato Descarboxilase/imunologia , Doença de Hashimoto/imunologia , Humanos , Receptores de GABA-B/imunologia
12.
Langmuir ; 37(28): 8498-8507, 2021 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-34231364

RESUMO

Controlled transport of surface-functionalized magnetic beads in a liquid medium is a central requirement for the handling of captured biomolecular targets in microfluidic lab-on-chip biosensors. Here, the influence of the physiological liquid medium on the transport characteristics of functionalized magnetic particles and on the functionality of the coupled protein is studied. These aspects are theoretically modeled and experimentally investigated for prototype superparamagnetic beads, surface-functionalized with green fluorescent protein immersed in buffer solution with different concentrations of a surfactant. The model reports on the tunability of the steady-state particle substrate separation distance to prevent their surface sticking via the choice of surfactant concentration. Experimental and theoretical average velocities are discussed for a ratchet-like particle motion induced by a dynamic external field superposed on a static locally varying magnetic field landscape. The developed model and experiment may serve as a basis for quantitative forecasts on the functionality of magnetic particle transport-based lab-on-chip devices.


Assuntos
Técnicas Biossensoriais , Tensoativos , Campos Magnéticos , Magnetismo , Microfluídica
13.
J Phys Chem A ; 124(14): 2736-2740, 2020 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-32183517

RESUMO

We report the first time-resolved resonant Raman (TR3) spectra of photoinduced charge transfer from [Ru(bpy)3]2+ to methyl viologen, with observations of vibrational structure. The presence of singly charged methyl viologen in solution is noted by the appearance of several spectroscopic lines, which are visible in the spectra following subtraction of reagent molecules. Assignments are confirmed using both density functional theory (DFT) calculations and literature values and are shown to be consistent with transient absorption spectroscopy data. This presents proof-of-concept for the application of TR3 in mechanistic studies of photocatalytic systems.

14.
Waste Manag Res ; 38(9): 1019-1027, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32552521

RESUMO

This study examined the effects of economic development on the commercialised and non-commercialised segments of informal food waste recycling in Da Nang City, Vietnam. Food waste was collected from the urban centre and used as pig feed in swine farms in suburban areas. The commercialised and non-commercialised segments of this system have evolved differently over time. During our observation period of 2011-2016, swine farmers became concerned about economic efficiency, which affected the manner in which they used food waste. By 2016, more farmers had begun to use food waste brokers instead of collecting food waste themselves so that they could concentrate on rearing pigs. The price of food waste remained low, reflecting the farmers' need for low-cost feeding. This resulted in the closure of commercialised transactions between households and waste collectors amid increased household income. Instead, non-commercialised transactions supported by human ties became the main mode of household participation in food waste recycling . Our findings can guide the use of different elements in this informal recycling system within the framework of a formalised recycling system implemented by the government.


Assuntos
Eliminação de Resíduos , Gerenciamento de Resíduos , Animais , Cidades , Desenvolvimento Econômico , Seguimentos , Alimentos , Humanos , Reciclagem , Suínos , Vietnã
16.
Eur Phys J E Soft Matter ; 42(5): 65, 2019 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-31119484

RESUMO

Petroleum reservoirs are remarkable illustrations of the impact of a thermal gradient on fluid pressure and composition. This topic has been extensively studied during the last decades to build tools that are required by reservoir engineers to populate their models. However, one can get only a very limited number of representative samples from a given reservoir and assessing connectivity between all sampling points is often a key issue. In some extreme cases, the whole reservoir fluid properties must be derived from a single point to define the field development plan. To do so, available models are usually not satisfactory as they need too many parameters and so cannot be considered as predictive tools. We propose in this work a comprehensive approach based on the irreversible thermodynamics principles to derive the relationships between pressure, chemical potentials and thermal gradients in porous media. It appears that there is no need for additional assumptions, it is just a matter of a making the right choices along theoretical developments. One of the most important steps is to express the full pressure gradient. As a final result, we obtain the chemical potential gradients for all components of the mixtures that can be easily translated in term of compositions through Equation of State modelling. The most important features of the final expressions are: i) the species relative separation in a thermal field is sensitive to the relative diffusion coefficients at stationary state. In porous media, the separation is sensitive to the permeability when the overall mobility is similar to diffusive mobility; ii) the magnitude of the separation depends on the residual entropy of the species; iii) the separation is not simply balanced by the average residual entropy. The balance is modified by the relative diffusion mobility of the components; iv) in low permeability porous media, the thermal gradient induces a pressure gradient proportional to the fluid residual entropy. As a validation, the proposed approach has been applied on a reservoir fluid subjected to a geothermal gradient and compared with non-equilibrium molecular dynamics simulation results at the stationary state.

17.
Eur Phys J E Soft Matter ; 42(5): 61, 2019 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-31093783

RESUMO

Noble gases, and the way they fractionate, is a promising approach to better constrain origin, migration and initial state distributions of fluids in gas and oil reservoirs. Thermodiffusion, is one of the phenomena that may lead to isotope and elemental fractionation of noble gases. However, this effect, assumed to be small, has not been quantified, nor measured, in oil and gas under reservoir conditions. Thus, in this work, molecular dynamics simulations have been performed to compute the thermal diffusion factors of noble gases, in a dense gas (methane) and in an oil (n-hexane) under high pressures. Interestingly, it has been found that thermal diffusion factors, associated to both isotopic (36Ar, 40Ar) and elemental fractionations of noble gases (4He, 20Ne, 40Ar, 84Kr and 131Xe) in gas and oil, could be expressed as linear functions of the reduced masses. Regarding the amplitude of the phenomena, it has been found that, in a stationary 1D oil or gas fluid column, thermodiffusion due to a typical geothermal gradient has an impact on noble gas isotopic and elemental fractionation which is of the same order of magnitude than gravity segregation, but opposite in sign. In addition, the relative impact of thermodiffusion on isotopic and elemental fractionations depends on the fluid type which is another interesting feature. Thus, these first numerical results on isotopic and elemental fractionation of noble gases by thermodiffusion in simple pure gas and oil emphasize their interest as natural tracers that could be used to improve the pre-exploitation description of oil and gas reservoirs.

18.
BMC Vet Res ; 14(1): 352, 2018 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-30453952

RESUMO

BACKGROUND: Senecavirus A, commonly known as Seneca Valley virus (SVV), is a picornavirus that has been infrequently associated with porcine idiopathic vesicular disease (PIVD). In late 2014 there were multiple PIVD outbreaks in several states in Brazil and samples from those cases tested positive for SVV. Beginning in July of 2015, multiple cases of PIVD were reported in the United States in which a genetically similar SVV was also detected. These events suggested SVV could induce vesicular disease, which was recently demonstrated with contemporary US isolates that produced mild disease in pigs. It was hypothesized that stressful conditions may exacerbate the expression of clinical disease and the following experiment was performed. Two groups of 9-week-old pigs were given an intranasal SVV challenge with one group receiving an immunosuppressive dose of dexamethasone prior to challenge. After challenge animals were observed for the development of clinical signs and serum and swabs were collected to study viral shedding and antibody production. In addition, pigs were euthanized 2, 4, 6, 8, and 12 days post inoculation (dpi) to demonstrate tissue distribution of virus during acute infection. RESULTS: Vesicular disease was experimentally induced in both groups with the duration and magnitude of clinical signs similar between groups. During acute infection [0-14 days post infection (dpi)], SVV was detected by PCR in serum, nasal swabs, rectal swabs, various tissues, and in swabs from ruptured vesicles. From 15 to 30 dpi, virus was less consistently detected in nasal and rectal swabs, and absent from most serum samples. Virus neutralizing antibody was detected by 5 dpi and lasted until the end of the study. CONCLUSION: Treatment with an immunosuppressive dose of dexamethasone did not drastically alter the clinical disease course of SVV in experimentally infected nursery aged swine. A greater understanding of SVV pathogenesis and factors that could exacerbate disease can help the swine industry with control and prevention strategies directed against this virus.


Assuntos
Dexametasona/farmacologia , Imunossupressores/farmacologia , Infecções por Picornaviridae/veterinária , Picornaviridae , Doenças dos Suínos/virologia , Animais , Animais Recém-Nascidos , Anticorpos Antivirais/sangue , Suínos , Doença Vesicular Suína/virologia , Eliminação de Partículas Virais/efeitos dos fármacos
19.
Proc Natl Acad Sci U S A ; 111(43): 15514-9, 2014 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-25313054

RESUMO

Inflammasomes are intracellular sensors that couple detection of pathogens and cellular stress to activation of Caspase-1, and consequent IL-1ß and IL-18 maturation and pyroptotic cell death. Here, we show that the absent in melanoma 2 (AIM2) and nucleotide-binding oligomerization domain-like receptor pyrin domain-containing protein 3 (NLRP3) inflammasomes trigger Caspase-1-dependent mitochondrial damage. Caspase-1 activates multiple pathways to precipitate mitochondrial disassembly, resulting in mitochondrial reactive oxygen species (ROS) production, dissipation of mitochondrial membrane potential, mitochondrial permeabilization, and fragmentation of the mitochondrial network. Moreover, Caspase-1 inhibits mitophagy to amplify mitochondrial damage, mediated in part by cleavage of the key mitophagy regulator Parkin. In the absence of Parkin activity, increased mitochondrial damage augments pyroptosis, as indicated by enhanced plasma membrane permeabilization and release of danger-associated molecular patterns (DAMPs). Therefore, like other initiator caspases, Caspase-1 activation by inflammasomes results in mitochondrial damage.


Assuntos
Caspase 1/metabolismo , Inflamassomos/metabolismo , Mitocôndrias/patologia , Mitofagia , Animais , Apoptose , Proteínas de Transporte/metabolismo , Síndromes Periódicas Associadas à Criopirina/enzimologia , Síndromes Periódicas Associadas à Criopirina/patologia , Proteínas de Ligação a DNA/metabolismo , Humanos , Camundongos Endogâmicos C57BL , Mitocôndrias/metabolismo , Membranas Mitocondriais/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR , Permeabilidade , Transdução de Sinais , Ubiquitina-Proteína Ligases/metabolismo
20.
Emerg Infect Dis ; 22(7): 1246-8, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27315363

RESUMO

Senecavirus A has been infrequently associated with vesicular disease in swine since 1988. However, clinical disease has not been reproduced after experimental infection with this virus. We report vesicular disease in 9-week-old pigs after Sencavirus A infection by the intranasal route under experimental conditions.


Assuntos
Infecções por Picornaviridae/veterinária , Picornaviridae , Doenças dos Suínos/virologia , Animais , Doenças do Pé/patologia , Doenças do Pé/veterinária , Doenças do Pé/virologia , Infecções por Picornaviridae/patologia , Infecções por Picornaviridae/virologia , Suínos , Doenças dos Suínos/patologia
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