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1.
Nano Lett ; 24(20): 6069-6077, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38739779

RESUMO

Nanoparticles (NPs) can be conjugated with diverse biomolecules and employed in biosensing to detect target analytes in biological samples. This proven concept was primarily used during the COVID-19 pandemic with gold-NP-based lateral flow assays (LFAs). Considering the gold price and its worldwide depletion, here we show that novel plasmonic NPs based on inexpensive metals, titanium nitride (TiN) and copper covered with a gold shell (Cu@Au), perform comparable to or even better than gold nanoparticles. After conjugation, these novel nanoparticles provided high figures of merit for LFA testing, such as high signals and specificity and robust naked-eye signal recognition. Since the main cost of Au NPs in commercial testing kits is the colloidal synthesis, our development with the Cu@Au and the laser-ablation-fabricated TiN NPs is exciting, offering potentially inexpensive plasmonic nanomaterials for various bioapplications. Moreover, our machine learning study showed that biodetection with TiN is more accurate than that with Au.


Assuntos
Cobre , Ouro , Nanopartículas Metálicas , Titânio , Nanopartículas Metálicas/química , Titânio/química , Ouro/química , Cobre/química , Técnicas Biossensoriais/métodos , Técnicas Biossensoriais/economia , Humanos , COVID-19/virologia , COVID-19/diagnóstico , Coloide de Ouro/química , SARS-CoV-2/isolamento & purificação
2.
Pharmacology ; 107(3-4): 216-226, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35073541

RESUMO

INTRODUCTION: The interindividual variability of the antiplatelet effect of clopidogrel is determined by multiple clinical and genetic factors. A lot of genotype-oriented studies have concentrated on the impact of CYP2C19 gene polymorphisms on platelet aggregation in patients receiving clopidogrel. However, the influence of this polymorphism may be only 12-20%, so other genetic markers should also be investigated. The aim of this work was to study the impact of carriage of CES1, PON1, ABCG2, CYP4F2, CYP3A4, IGTB3, P2Y12, PEAR1, and B4GALT2 polymorphisms on antiplatelet effect of clopidogrel and clinical outcomes in patients with acute coronary syndrome (ACS) and atrial fibrillation (AF). METHODS: 103 patients who underwent ACS with or without percutaneous coronary intervention and concomitant nonvalvular AF were included in an open multicenter prospective study to assess efficacy and safety of combined antithrombotic therapy. The study assessed the frequency of different primary clinical outcomes (incidence of major bleeding, hospital mortality, cardiovascular mortality, stroke and transient ischemic attacks (TIAs), renal mortality) and secondary outcomes (resistance to therapy - high residual platelet reactivity, excessive platelet suppression). Residual platelet reactivity was examined using the VerifyNow system (Accumetrics, Latham, NY, USA). RESULTS: None of the studied genetic markers had no statistically significant effect on the antiaggregant response to clopidogrel in patients with ACS and AF. However, CYP4F2 C(Val433Met) T, PEAR1 rs41273215 C>T were statistically significantly associated with an increased frequency of bleeding on antithrombotic therapy. B4GALT2 rs1061781 was statistically significantly associated with increased frequency of strokes and TIA. CONCLUSION: In our study, we determined that carriers of CYP4F2 gene polymorphisms C(Val433Met)T, PEAR1 rs41273215 C>T (CT+TT) were associated with lower safety of antithrombotic therapy in patients with ACS and AF. And, the B4GALT2 rs1061781 gene polymorphism was associated with a greater risk of insufficient efficacy of the therapy. The data obtained in our study may improve the understanding of the effect of less studied genetic markers on the efficacy and safety of antithrombotic therapy in patients with ACS and AF.


Assuntos
Síndrome Coronariana Aguda , Fibrilação Atrial , Intervenção Coronária Percutânea , Síndrome Coronariana Aguda/tratamento farmacológico , Síndrome Coronariana Aguda/genética , Arildialquilfosfatase/genética , Arildialquilfosfatase/uso terapêutico , Fibrilação Atrial/induzido quimicamente , Fibrilação Atrial/tratamento farmacológico , Fibrilação Atrial/genética , Clopidogrel/efeitos adversos , Citocromo P-450 CYP2C19/genética , Humanos , Intervenção Coronária Percutânea/efeitos adversos , Inibidores da Agregação Plaquetária/efeitos adversos , Estudos Prospectivos , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/uso terapêutico , Ticlopidina/efeitos adversos , Resultado do Tratamento
3.
Int J Mol Sci ; 21(9)2020 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-32365879

RESUMO

Phytopathogenic bacteria belonging to the Pectobacterium and Dickeya genera (soft-rot Pectobacteriaceae) are in the focus of agriculture-related microbiology because of their diversity, their substantial negative impact on the production of potatoes and vegetables, and the prospects of bacteriophage applications for disease control. Because of numerous amendments in the taxonomy of P. carotovorum, there are still a few studied sequenced strains among this species. The present work reports on the isolation and characterization of the phage infectious to the type strain of P. carotovorum. The phage Arno 160 is a lytic Podovirus representing a potential new genus of the subfamily Autographivirinae. It recognizes O-polysaccahride of the host strain and depolymerizes it in the process of infection using a rhamnosidase hydrolytic mechanism. Despite the narrow host range of this phage, it is suitable for phage control application.


Assuntos
Bacteriófagos/fisiologia , Pectobacterium carotovorum/metabolismo , Pectobacterium carotovorum/virologia , Sequência de Aminoácidos , Bacteriófagos/ultraestrutura , Genoma Viral , Genômica , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Conformação Molecular , Filogenia , Polimerização , Polissacarídeos Bacterianos/química , Ligação Proteica , Proteínas Virais/química
4.
Langmuir ; 33(37): 9444-9454, 2017 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-28723093

RESUMO

We use plasmonic Au-TiO2 aerogels as a platform in which to marry synthetically thickened particle-particle junctions in TiO2 aerogel networks to Au∥TiO2 interfaces and then investigate their cooperative influence on photocatalytic hydrogen (H2) generation under both broadband (i.e., UV + visible light) and visible-only excitation. In doing so, we elucidate the dual functions that incorporated Au can play as a water reduction cocatalyst and as a plasmonic sensitizer. We also photodeposit non-plasmonic Pt cocatalyst nanoparticles into our composite aerogels in order to leverage the catalytic water-reducing abilities of Pt. This Au-TiO2/Pt arrangement in three dimensions effectively utilizes conduction-band electrons injected into the TiO2 aerogel network upon exciting the Au SPR at the Au∥TiO2 interface. The extensive nanostructured high surface-area oxide network in the aerogel provides a matrix that spatially separates yet electrochemically connects plasmonic nanoparticle sensitizers and metal nanoparticle catalysts, further enhancing solar-fuels photochemistry. We compare the photocatalytic rates of H2 generation with and without Pt cocatalysts added to Au-TiO2 aerogels and demonstrate electrochemical linkage of the SPR-generated carriers at the Au∥TiO2 interfaces to downfield Pt nanoparticle cocatalysts. Finally, we investigate visible light-stimulated generation of conduction band electrons in Au-TiO2 and TiO2 aerogels using ultrafast visible pump/IR probe spectroscopy. Substantially more electrons are produced at Au-TiO2 aerogels due to the incorporated SPR-active Au nanoparticle, whereas the smaller population of electrons generated at Au-free TiO2 aerogels likely originate at shallow traps in the high surface-area mesoporous aerogel.

5.
Electrochim Acta ; 213: 482-489, 2016 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-27695133

RESUMO

The effects of bromomethane (BrCH3), an airborne contaminant, on the performance of a single PEMFC are compared with that of another halocarbon, chlorobenzene. Under a constant current of 1 A cm-2 and at 45 °C, 20 ppm bromomethane causes approximately 30% cell voltage loss in approximately 30 h, as opposed to much more rapid performance degradation observed with chlorobenzene. Electrochemical impedance spectroscopy, cyclic voltammetry, linear scanning voltammetry, and polarization measurements are applied to characterize the temporary electrochemical reaction effect and permanent performance effects. X-ray absorption spectroscopy is used to confirm that Br is adsorbed on the Pt electrocatalyst surface. We conclude that airborne bromomethane poisons a PEMFC in a different way from chlorobenzene because it is largely hydrolyzed to bromide, Br-, which is then excluded from the Pt catalyst by the negatively charged Nafion ionomer. The little Br- and bromomethane that adsorbs on the Pt surface can be partially removed by cycling but causes some irreversible surface area loss.

6.
Mult Scler Relat Disord ; 91: 105910, 2024 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-39369632

RESUMO

BACKGROUND: Relapsing-remitting multiple sclerosis (RRMS) is a most common form of multiple sclerosis in which periods of neurological worsening are followed by periods of clinical remission. RRMS relapses are caused by an acute autoimmune inflammatory process, which can occur in any area of the central nervous system. Although development of exacerbation cannot yet be accurately predicted, various external factors are known to affect its risk. These factors may trigger the pathological process through epigenetic mechanisms of gene expression regulation, first of all, through changes in DNA methylation. METHODS: In the present work, we for the first time analyzed genome-wide DNA methylation patterns in CD4+ T lymphocytes and CD14+ monocytes of the same RRMS patients in relapse and remission. The effects of the differential methylation on gene expression were studied using qPCR. RESULTS: We found 743 differentially methylated CpG positions (DMPs) in CD4+ cells and only 113 DMPs in CD14+ cells. They were mostly hypermethylated in RRMS relapse in both cell populations. However, the proportion of hypermethylated DMPs (as well as DMPs located within or in close proximity to CpG islands) was significantly higher in CD4+ T lymphocytes. In CD4+ and CD14+ cells we identified 469 and 67 DMP-containing genes, respectively; 25 of them were common for two cell populations. When we conducted a search for differentially methylated genomic regions (DMRs), we found a CD4+ specific DMR hypermethylated in RRMS relapse (adj. p = 0.03) within the imprinted GNAS locus. Total level of the protein-coding GNAS transcripts in CD4+ T cells decreased significantly in the row from healthy control to RRMS remission and then to RRMS relapse (adj. p = 3.1 × 10-7 and 0.011, respectively). CONCLUSION: Our findings suggest that the epigenetic mechanism of DNA methylation in immune cells contributes to the development of RRMS relapse. Further studies are now required to validate these results and shed light on the molecular mechanisms underlying the observed GNAS methylation and expression changes.

7.
Sci Rep ; 14(1): 15342, 2024 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-38961196

RESUMO

Mitochondrial forms account approximately 1-2% of all nonsyndromic cases of hearing loss (HL). One of the most common causative variants of mtDNA is the m.1555A > G variant of the MT-RNR1 gene (OMIM 561000). Currently the detection of the m.1555A > G variant of the MT-RNR1 gene is not included in all research protocols. In this study this variant was screened among 165 patients with HL from the Republic of Buryatia, located in the Baikal Lake region of Russia. In our study, the total contribution of the m.1555A > G variant to the etiology of HL was 12.7% (21/165), while the update global prevalence of this variant is 1.8% (863/47,328). The m.1555A > G variant was notably more prevalent in Buryat (20.2%) than in Russian patients (1.3%). Mitogenome analysis in 14 unrelated Buryat families carrying the m.1555A > G variant revealed a predominant lineage: in 13 families, a cluster affiliated with sub-haplogroup A5b (92.9%) was identified, while one family had the D5a2a1 lineage (7.1%). In a Russian family with the m.1555A > G variant the lineage affiliated with sub-haplogroup F1a1d was found. Considering that more than 90% of Buryat families with the m.1555A > G variant belong to the single maternal lineage cluster we conclude that high prevalence of this variant in patients with HL in the Baikal Lake region can be attributed to a founder effect.


Assuntos
DNA Mitocondrial , Efeito Fundador , Perda Auditiva , Humanos , Federação Russa/epidemiologia , Feminino , Masculino , Perda Auditiva/genética , Perda Auditiva/epidemiologia , Prevalência , DNA Mitocondrial/genética , Adulto , Criança , Adolescente , Haplótipos , Pré-Escolar , Pessoa de Meia-Idade , Lagos , Adulto Jovem
8.
bioRxiv ; 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38260353

RESUMO

Nanoparticles (NPs) can be conjugated with diverse biomolecules and employed in biosensing to detect target analytes in biological samples. This proven concept was primarily used during the COVID-19 pandemic with gold NPs-based lateral flow assays (LFAs). Considering the gold price and its worldwide depletion, here we show that novel plasmonic nanoparticles (NPs) based on inexpensive metals, titanium nitride (TiN) and copper covered with a gold shell (Cu@Au), perform comparable or even better than gold nanoparticles. After conjugation, these novel nanoparticles provided high figures of merit for LFA testing, such as high signals and specificity and robust naked-eye signal recognition. To the best of our knowledge, our study represents the 1st application of laser-ablation-fabricated nanoparticles (TiN) in the LFA and dot-blot biotesting. Since the main cost of the Au NPs in commercial testing kits is in the colloidal synthesis, our development with TiN is very exciting, offering potentially very inexpensive plasmonic nanomaterials for various bio-testing applications. Moreover, our machine learning study showed that the bio-detection with TiN is more accurate than that with Au.

9.
Microorganisms ; 11(10)2023 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-37894089

RESUMO

Managing soil biodiversity using reduced tillage is a popular approach, yet soil bacteriobiomes in the agroecosystems of Siberia has been scarcely studied, especially as they are related to tillage. We studied bacteriobiomes in Chernozem under natural steppe vegetation and cropped for wheat using conventional or no tillage in a long-term field trial in the Novosibirsk region, Russia, by using the sequence diversity of the V3/V4 region of 16S rRNA genes. Actinobacteria, Acidobacteria, and Proteobacteria summarily accounted for 80% of the total number of sequences, with Actinobacteria alone averaging 51%. The vegetation (natural vs. crop) and tillage (ploughed vs. no-till) affected the bacterial relative abundance at all taxonomic levels and many taxa, e.g., hundreds of OTUs. However, such changes did not translate into α-biodiversity changes, i.e., observed and potential OTUs' richness, Shannon, and Simpson, excepting the slightly higher evenness and equitability in the top 0-5 cm of the undisturbed soil. As for the ß-biodiversity, substituting conventional ploughing with no tillage and maintaining the latter for 12 years notably shifted the soil bacteriobiome closer to the one in the undisturbed soil. This study, presenting the first inventory of soil bacteriobiomes under different tillage in the south of West Siberia, underscores the need to investigate the seasonality and longevity aspects of tillage, especially as they are related to crop production.

10.
J Pers Med ; 13(9)2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37763139

RESUMO

Objective: This study's objective was to evaluate the effects of pharmacokinetic and pharmacogenetic factors on major bleeding in patients with ACS and non-valvular AF receiving combined antithrombotic therapy consisting of rivaroxaban, clopidogrel, and aspirin as part of dual or triple therapy. Methods: A prospective observational study was conducted in two PCI centers in Moscow, the Russian Federation, from 2017 to 2018. One hundred patients with ACS and AF were enrolled. Prospective follow-ups continued for 12 months. Results: A total of 36 patients experienced bleeding events, with 10 experiencing major bleeding based on the BARC scale and 17 experiencing major bleeding based on the ISTH scale. The following predictors associated with an increased number of major bleeding events were identified: for the ISTH scale, a Css min. of rivaroxaban of >137 pg/mL (5.94 OR, (95% CI, 3.13-12.99; p < 0.004)) and carriage of the T allelic variant polymorphism ABCB1 rs4148738 (8.97 OR (95% CI, 1.48-14.49; p < 0.017)), as well as for the BARC scale (5.76 OR (95% CI, 2.36-9.87; p < 0.018)). Conclusions: Measuring residual steady-state rivaroxaban concentrations and determining the carriage of the T allelic variant polymorphism ABCB1 rs4148738 may be applicable to high-risk patients for subsequent antithrombotic therapy modification.

11.
Microorganisms ; 12(1)2023 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-38257907

RESUMO

The present study aimed to investigate the recovery of soil quality and the bacterial and fungal communities following various recultivation methods in areas contaminated with oil. Oil spills are known to have severe impacts on ecosystems; thus, the restoration of contaminated soils has become a significant challenge nowadays. The study was conducted in the forest-tundra zone of the European North-East, where 39 soil samples from five oil-contaminated sites and reference sites were subjected to metagenomic analyses. The contaminated sites were treated with different biopreparations, and the recovery of soil quality and microbial communities were analyzed. The analysis of bacteria and fungi communities was carried out using 16S rDNA and ITS metabarcoding. It was found that 68% of bacterial OTUs and 64% of fungal OTUs were unique to the reference plot and not registered in any of the recultivated plots. However, the species diversity of recultivated sites was similar, with 50-80% of bacterial OTUs and 44-60% of fungal OTUs being common to all sites. New data obtained through soil metabarcoding confirm our earlier conclusions about the effectiveness of using biopreparations with indigenous oil-oxidizing micro-organisms also with mineral fertilizers, and herbaceous plant seeds for soil remediation. It is possible that the characteristics of microbial communities will be informative in the bioindication of soils reclaimed after oil pollution.

12.
Nanomaterials (Basel) ; 12(5)2022 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-35269325

RESUMO

Herein, we find that TiN sputter-deposited on GaN displayed the desired optical properties for plasmonic applications. While this is a positive result indicating the possible use of p- or n-type GaN as a collector of plasmonically generated hot carriers, the interfacial properties differed considerably depending on doping conditions. On p-type GaN, a distinct Schottky barrier was formed with a barrier height of ~0.56 eV, which will enable effective separation of photogenerated electrons and holes, a typical approach used to extend their lifetimes. On the other hand, no transport barrier was found for TiN on n-type GaN. While the lack of spontaneous carrier separation in this system will likely reduce unprompted hot carrier collection efficiencies, it enables a bias-dependent response whereby charges of the desired type (e.g., electrons) could be directed into the semiconductor or sequestered in the plasmonic material. The specific application of interest would determine which of these conditions is most desirable.

13.
Life (Basel) ; 12(8)2022 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-36013348

RESUMO

Managing soil biodiversity by reduced or no tillage is an increasingly popular approach. Soil mycobiome in Siberian agroecosystems has been scarcely studied; little is known about its changes due to tillage. We studied mycobiome in Chernozem under natural steppe vegetation and cropped for wheat by conventional or no tillage in a long-term field trial in West Siberia, Russia, by using ITS2 rDNA gene marker (Illumina MiSeq sequencing). Half of the identified OTUs were Ascomycota with 82% of the total number of sequence reads and showing, like other phyla (Basidiomycota, Zygomycota, Mortierellomycota, Chytridiomycota, Glomeromycota), field-related differential abundance. Several dominant genera (Mortierella, Chaetomium, Clonostachys, Gibberella, Fusarium, and Hypocrea) had increased abundance in both cropped soils as compared with the undisturbed one and therefore can be safely assumed to be associated with wheat residues. Fungal OTUs' richness in cropped soils was less than in the undisturbed one; however, no tillage shifted soil mycobiome composition closer to the latter, albeit, it was still similar to the ploughed soil, despite different organic matter and wheat residue content. The study provided the first inventory of soil mycobiome under different tillage treatments in the south of West Siberia, where wheat production is an important section of the regional economy.

14.
Mult Scler Relat Disord ; 60: 103714, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35245816

RESUMO

Multiple sclerosis (MS) is a chronic autoimmune and degenerative disease of the central nervous system, which develops in genetically predisposed individuals upon exposure to environmental influences. Environmental triggers of MS, such as viral infections or smoking, were demonstrated to affect DNA methylation, and thus to involve this important epigenetic mechanism in the development of pathological process. To identify MS-associated DNA methylation hallmarks, we performed genome-wide DNA methylation profiling of two cell populations (CD4+ T-lymphocytes and CD14+ monocytes), collected from the same treatment-naive relapsing-remitting MS patients and healthy subjects, using Illumina 450 K methylation arrays. We revealed significant changes in DNA methylation for both cell populations in MS. In CD4+ cells of MS patients the majority of differentially methylated positions (DMPs) were shown to be hypomethylated, while in CD14+ cells - hypermethylated. Differential methylation of HLA-DRB1 gene in CD4+ and CD14+ cells was associated with carriage of DRB1*15 allele independently from the disease status. Besides, about 20% of identified DMPs were shared between two cell populations and had the same direction of methylation changes; they may be involved in basic epigenetic processes occuring in MS. These findings suggest that the epigenetic mechanism of DNA methylation in immune cells contributes to MS; further studies are now required to validate these results and understand their functional significance.


Assuntos
Linfócitos T CD4-Positivos , Metilação de DNA , Receptores de Lipopolissacarídeos , Esclerose Múltipla Recidivante-Remitente , Esclerose Múltipla , Linfócitos T CD4-Positivos/metabolismo , Epigênese Genética , Humanos , Receptores de Lipopolissacarídeos/genética , Receptores de Lipopolissacarídeos/metabolismo , Esclerose Múltipla/genética , Esclerose Múltipla/metabolismo , Esclerose Múltipla Recidivante-Remitente/genética , Esclerose Múltipla Recidivante-Remitente/metabolismo
15.
ACS Appl Mater Interfaces ; 14(7): 9655-9666, 2022 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-35134290

RESUMO

Robust materials capable of heterogeneous reactivity are valuable for addressing toxic chemical clean up. Synthetic manipulations for generating titanium oxide nanomaterials have been utilized to alter both photochemical (1000 nm > λ > 400 nm) and chemical heterogeneous reactivity with 2-chloroethyl ethyl sulfide (2-CEES). Synthesizing TiO2 nanomaterials in the presence of long-chain alkylphosphonic acids enhanced the visible light-driven oxidation of the thioether sulfur of 2-CEES. Photooxidation reaction rates of 99 and 168 µmol/g/h (quantum yields of 5.07 × 10-4 and 8.58 × 10-4 molecules/photon, respectively) were observed for samples made with two different alkylphosphonic acids (C14H29PO3H2 and C9H19PO3H2, respectively). These observations are correlated with (i) generation of new surface defects/states (i.e., oxygen vacancies) as a result of TiO2 grafting by alkylphosphonic acid that may serve as reaction active sites, (ii) better light absorption by assemblies of nanorods and nanowires in comparison to individual nanorods, (iii) surface area differences, and (iv) the exclusion of OH groups due to the surface functionalization with alkylphosphonic acids via Ti-O-P bonds on the TiO2. Alternatively, nanowire-form H2Ti2O5·H2O was produced and found to be capable of highly efficient hydrolysis of the carbon-chlorine (C-Cl) bond of 2-CEES in the dark with a reaction rate of 279.2 µmol/g/h due to the high surface area and chemical nature of the titanate structure.

16.
Microbiol Resour Announc ; 11(3): e0108821, 2022 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-35225668

RESUMO

Sinorhizobium meliloti is a symbiotic bacterial species forming nitrogen-fixing nodules on roots of annual and perennial Medicago spp. We report the full genome sequence of S. meliloti strain AK76, an effective symbiont of the wild diploid plant Medicago lupulina grown in the Mugodgary Mountain region, Kazakhstan.

17.
Langmuir ; 27(24): 14930-9, 2011 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-22047613

RESUMO

Electrochemical adsorption of SO(2) on platinum is complicated by the change in sulfur oxidation state with potential. Here, we attempt to identify SO(2) adsorption products on catalyst coated membranes (CCMs) at different electrode potentials using a combination of in situ sulfur K-edge XANES (X-ray absorption near-edge structure) spectroscopy and electrochemical techniques. CCMs employed platinum nanoparticles supported on Vulcan carbon (Pt/VC). SO(2) was adsorbed from a SO(2)/N(2) gas mixture while holding the Pt/VC-electrode potential at 0.1, 0.5, 0.7, and 0.9 V vs a reversible hydrogen electrode (RHE). Sulfur adatoms (S(0)) are identified as the SO(2) adsorption products at 0.1 V, while mixtures of S(0), SO(2), and sulfate/bisulfate ((bi)sulfate) ions are suggested as SO(2) adsorption products at 0.5 and 0.7 V. At 0.9 V, SO(2) is completely oxidized to (bi)sulfate ions. The identity of adsorbed SO(2) species on Pt/VC catalysts at different electrode potentials is confirmed by modeling of XANES spectra using FEFF8 and a linear combination of experimental spectra from sulfur standards. Results on SO(2) speciation gained from XANES are used to compare platinum-sulfur electronic interactions for Pt(3)Co/VC versus Pt/VC catalysts in order to understand the difference between the two catalysts in terms of SO(2) contamination.

18.
Microbiol Resour Announc ; 10(11)2021 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-33737367

RESUMO

The genome of a symbiotically effective salt-tolerant strain, Sinorhizobium meliloti S35m, isolated from alfalfa rhizosphere in soil native to the Caucasus region, was sequenced. Genomic islands, prophages, and elements of a potential CRISPR/Cas I type (Cas3_0_I) system were identified in the genome.

19.
Anal Chem ; 82(15): 6321-8, 2010 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-20590161

RESUMO

A tutorial is provided for methods to accurately and reproducibly determine the activity of Pt-based electrocatalysts for the oxygen reduction reaction in proton exchange membrane fuel cells and other applications. The impact of various experimental parameters on electrocatalyst activity is demonstrated, and explicit experimental procedures and measurement protocols are given for comparison of electrocatalyst activity to fuel cell standards. (To listen to a podcast about this article, please go to the Analytical Chemistry multimedia page at pubs.acs.org/page/ancham/audio/index.html.).

20.
Int J Nephrol Renovasc Dis ; 12: 113-118, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31190950

RESUMO

Background: Determining the prognosis of heart failure with preserved ejection fraction (HFpEF) is problematic, as the ejection fraction cannot be used. Formulae that estimate glomerular filtration rate (eGFR) may be potential prognosticators for this condition, since renal dysfunction is a well-known predictor of poor outcomes of all forms of heart failure. Methods: A prospective observational study of 117 HFpEF patients (average age 71.6±9.1 years; 65.8% women) who had eGFR determined after their first episode of cardiac decompensation by two different chronic kidney disease epidemiology collaboration (CKD-EPI) equations. The ability to predict hospitalizations and mortality over 24 months by the two equations were compared. Results: The CKD-EPI formula based on serum creatinine only performed poorly. However, the CKD-EPI equation that used both serum creatinine and serum cystatin C was associated with unfavorable outcome: eGFR <45 mL/min/1.73 m2 predicted 24-month mortality (HR=4.21 [1.32;13.43], p=0.02) and the combined endpoint of mortality and hospitalization (HR 2.45 [1.42;4.22], p=0.001). . Conclusions: eGFR by the CKD-EPI equation based on serum creatinine and cystatin C levels, but not by the CKD-EPI creatinine only equation, predicts the outcome of HFpEF patients.

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