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1.
Phys Chem Chem Phys ; 25(5): 3900-3911, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36648114

RESUMO

We report on the controlled synthesis and functionalization in two steps of elongated Bi2S3 nanoparticles within a wide range of sizes. First, we show the effect of the temperature and reaction time on the synthesis of two series of nanoparticles by the reaction of thioacetamide with bismuth(III) neodecanoate in the presence of organic surfactants. At 105 °C and long reaction times, nanoneedles of about 45 nm in length containing larger crystallites are obtained, while highly crystalline nanorods of about 30 nm in length are dominant at 165 °C, regardless of the reaction time. The optical properties of both types of nanoparticles show an enhancement of the band gap compared to bulk Bi2S3. This is likely to arise from quantum confinement effects caused by the small particle dimensions relative to the typical exciton size, together with an increase in near-infrared absorption due to the anisotropic particle shape. Second, a ligand exchange approach has been developed to transfer the Bi2S3 nanoparticles to aqueous solutions by grafting dimercaptosuccinic acid onto the surface of the particles. The as-prepared coated nanoparticles show good stability in water, in a wide biological pH range, and in phosphate-buffered saline solutions. Overall, this work highlights the controlled design at all levels - from the inorganic core to the organic surface coating - of elongated Bi2S3 nanoparticles, leading to a tunable optical response by tuning their morphology and size.

2.
Int J Mol Sci ; 24(5)2023 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-36901992

RESUMO

There is considerable controversy regarding the genotoxicity of glyphosate (N-(phosphonomethyl) glycine). It has been suggested that the genotoxicity of this herbicide is increased by the adjuvants added to commercial formulations based on glyphosate. The effect of various concentrations of glyphosate and three commercial glyphosate-based herbicides (GBH) on human lymphocytes was evaluated. Human blood cells were exposed to glyphosates of 0.1, 1, 10 and 50 mM as well as to equivalent concentrations of glyphosate on commercial formulations. Genetic damage (p < 0.05) was observed in all concentrations with glyphosate and with FAENA and TACKLE formulations. These two commercial formulations showed genotoxicity that was concentration-dependent but in a higher proportion compared to pure glyphosate only. Higher glyphosate concentrations increased the frequency and range of tail lengths of some migration groups, and the same was observed for FAENA and TACKLE, while in CENTELLA the migration range decreased but the frequency of migration groups increased. We show that pure glyphosate and commercial GBH (FAENA, TACKLE and CENTELLA) gave signals of genotoxicity in human blood samples in the comet assay. The genotoxicity increased in the formulations, indicating genotoxic activity also in the added adjuvants present in these products. The use of the MG parameter allowed us to detect a certain type of genetic damage associated with different formulations.


Assuntos
Herbicidas , Humanos , Ensaio Cometa , Células Sanguíneas , Glicina , Adjuvantes Imunológicos , Adjuvantes Farmacêuticos , Glifosato
3.
Molecules ; 28(12)2023 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-37375274

RESUMO

Satureja macrostema is a plant that is located in various regions of Mexico and is used in a traditional way against illness. Essential oils (EOs) were obtained from leaves Satureja macrostema and the chemical composition was evaluated by gas chromatography-mass spectrometry (GC-MS). The antioxidant effect of the oil was assayed by 2,2-diphenyl-1-picrylhydrazyl (DPPH) and by Trolox Equivalent Antioxidant Capacity (TEAC). In vitro antibacterial activity against Escherichia coli and Staphylococcus aureus was determined using a broth microdilution assay and thin layer chromatography-direct bioautography (TLC-DB) to identify active antibacterial compounds. The EOs analysis showed 21 compounds, 99% terpenes, and 96% oxygenated monoterpenes, with trans-piperitone epoxide (46%), cis-piperitone epoxide (22%), and piperitenone oxide (11%) as more abundant compounds. Likewise, S. macrostema EOs showed an antioxidant activity of DPPH = 82%, with 50% free radical scavenging (IC50) = 7 mg/mL and TEAC = 0.005, an antibacterial effect against E. coli of 73% inhibition, and 81% over S. aureus at dose of 100 µL of undiluted crude oil. The TLC-DB assay showed that the most active compounds were derived from piperitone. The comparison with other studies on S. macrostema shows variability in the compounds and their abundances, which can be attributed to climatic factors and the maturity of plants with similar antioxidant and antibacterial activities.


Assuntos
Lamiaceae , Óleos Voláteis , Satureja , Antioxidantes/farmacologia , Antioxidantes/química , Óleos Voláteis/farmacologia , Óleos Voláteis/química , Satureja/química , Escherichia coli , Staphylococcus aureus , Antibacterianos/farmacologia , Antibacterianos/química , Lamiaceae/química , Óleos de Plantas/química
4.
BMC Genomics ; 23(1): 465, 2022 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-35751020

RESUMO

BACKGROUND: Type 2 diabetes mellitus (T2DM) has been associated with treatment failure, and the development of drug resistance in tuberculosis (TB). Also, whole-genome sequencing has provided a better understanding and allowed the growth of knowledge about polymorphisms in genes associated with drug resistance. Considering the above, this study analyzes genome sequences to evaluate the influence of type 2 diabetes mellitus in the development of mutations related to tuberculosis drug resistance. M. tuberculosis isolates from individuals with (n = 74), and without (n = 74) type 2 diabetes mellitus was recovered from online repositories, and further analyzed. RESULTS: The results showed the presence of 431 SNPs with similar proportions between diabetics, and non-diabetics individuals (48% vs. 52%), but with no significant relationship. A greater number of mutations associated with rifampicin resistance was observed in the T2DM-TB individuals (23.2% vs. 16%), and the exclusive presence of rpoBQ432L, rpoBQ432P, rpoBS441L, and rpoBH445L variants. While these variants are not private to T2DM-TB cases they are globally rare highlighting a potential role of T2DM. The phylogenetic analysis showed 12 sublineages, being 4.1.1.3, and 4.1.2.1 the most prevalent in T2DM-TB individuals but not differing from those most prevalent in their geographic location. Four clonal complexes were found, however, no significant relationship with T2DM was observed. Samples size and potential sampling biases prevented us to look for significant associations. CONCLUSIONS: The occurrence of globally rare rifampicin variants identified only in isolates from individuals with T2DM could be due to the hyperglycemic environment within the host. Therefore, further studies about the dynamics of SNPs' generation associated with antibiotic resistance in patients with diabetes mellitus are necessary.


Assuntos
Diabetes Mellitus Tipo 2 , Mycobacterium tuberculosis , Tuberculose Resistente a Múltiplos Medicamentos , Tuberculose , Antituberculosos/farmacologia , Antituberculosos/uso terapêutico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/genética , Farmacorresistência Bacteriana Múltipla/genética , Humanos , Testes de Sensibilidade Microbiana , Filogenia , Polimorfismo de Nucleotídeo Único , Rifampina/uso terapêutico , Tuberculose/tratamento farmacológico , Tuberculose/epidemiologia , Tuberculose/genética , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Tuberculose Resistente a Múltiplos Medicamentos/genética , Sequenciamento Completo do Genoma
5.
BMC Genomics ; 23(1): 435, 2022 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-35692040

RESUMO

BACKGROUND: Needle rust caused by the fungus Chrysomyxa rhododendri causes significant growth decline and increased mortality of young Norway spruce trees in subalpine forests. Extremely rare trees with enhanced resistance represent promising candidates for practice-oriented reproduction approaches. They also enable the investigation of tree molecular defence and resistance mechanisms against this fungal disease. Here, we combined RNA-Seq, RT-qPCR and secondary metabolite analyses during a period of 38 days following natural infection to investigate differences in constitutive and infection-induced defence between the resistant genotype PRA-R and three susceptible genotypes. RESULTS: Gene expression and secondary metabolites significantly differed among genotypes from day 7 on and revealed already known, but also novel candidate genes involved in spruce molecular defence against this pathogen. Several key genes related to (here and previously identified) spruce defence pathways to needle rust were differentially expressed in PRA-R compared to susceptible genotypes, both constitutively (in non-symptomatic needles) and infection-induced (in symptomatic needles). These genes encoded both new and well-known antifungal proteins such as endochitinases and chitinases. Specific genetic characteristics concurred with varying phenolic, terpene, and hormone needle contents in the resistant genotype, among them higher accumulation of several flavonoids (mainly kaempferol and taxifolin), stilbenes, geranyl acetone, α-ionone, abscisic acid and salicylic acid. CONCLUSIONS: Combined transcriptional and metabolic profiling of the Norway spruce defence response to infection by C. rhododendri in adult trees under subalpine conditions confirmed the results previously gained on artificially infected young clones in the greenhouse, both regarding timing and development of infection, and providing new insights into genes and metabolic pathways involved. The comparison of genotypes with different degrees of susceptibility proved that several of the identified key genes are differently regulated in PRA-R, and that the resistant genotype combines a strong constitutive defence with an induced response in infected symptomatic needles following fungal invasion. Genetic and metabolic differences between the resistant and susceptible genotypes indicated a more effective hypersensitive response (HR) in needles of PRA-R that prevents penetration and spread of the rust fungus and leads to a lower proportion of symptomatic needles as well as reduced symptom development on the few affected needles.


Assuntos
Picea , Perfilação da Expressão Gênica , Imunidade Inata , Picea/microbiologia , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Árvores/genética , Bexiga Urinária
6.
Curr Issues Mol Biol ; 44(5): 2230-2242, 2022 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-35678680

RESUMO

Glyphosate is a controversial herbicide. Its genotoxicity and presence in various ecosystems have been reported. The use of ascorbic acid and resveratrol could protect different organisms from glyphosate-induced genetic damage. In the present study, specific genetic damage induced by glyphosate was evaluated in erythrocytes of Oreochromis niloticus, Ambystoma mexicanum and human lymphocytes. Simultaneously, the antigenotoxic capacity of various concentrations of ascorbic acid and resveratrol was evaluated by means of pretreatment and simultaneous treatment protocols. The 0.03, 0.05 and 0.07 mM concentrations of glyphosate induced significant genotoxic activity (p < 0.05) in human lymphocytes and in erythrocytes of the species studied, and could cause genomic instability in these populations. The reduction in genetic damage observed in human lymphocytes exposed to high concentrations of glyphosate is only apparent: excessive genetic damage was associated with undetectable excessive tail migration length. A significant (p < 0.05) antigenotoxic effect of ascorbic acid and resveratrol was observed in all concentrations, organisms and protocols used. Both ascorbic acid and resveratrol play an important role in maintaining the integrity of DNA. Ascorbic acid in Oreochromis niloticus, Ambystoma mexicanum reduced glyphosate-induced genetic damage to a basal level. Therefore, our data indicate that these antioxidants could help preserve the integrity of the DNA of organisms exposed to glyphosate. The consumption of antioxidants is a useful tool against the genotoxicity of glyphosate.

7.
Molecules ; 27(12)2022 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-35744920

RESUMO

Magnetic composites and self-healing materials have been drawing much attention in their respective fields of application. Magnetic fillers enable changes in the material properties of objects, in the shapes and structures of objects, and ultimately in the motion and actuation of objects in response to the application of an external field. Self-healing materials possess the ability to repair incurred damage and consequently recover the functional properties during healing. The combination of these two unique features results in important advances in both fields. First, the self-healing ability enables the recovery of the magnetic properties of magnetic composites and structures to extend their service lifetimes in applications such as robotics and biomedicine. Second, magnetic (nano)particles offer many opportunities to improve the healing performance of the resulting self-healing magnetic composites. Magnetic fillers are used for the remote activation of thermal healing through inductive heating and for the closure of large damage by applying an alternating or constant external magnetic field, respectively. Furthermore, hard magnetic particles can be used to permanently magnetize self-healing composites to autonomously re-join severed parts. This paper reviews the synthesis, processing and manufacturing of magnetic self-healing composites for applications in health, robotic actuation, flexible electronics, and many more.


Assuntos
Magnetismo , Robótica , Campos Magnéticos
8.
Langmuir ; 37(1): 35-45, 2021 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-33301314

RESUMO

Iron oxide nanoparticles (NPs) have been extensively used for both health and technological applications. The control over their morphology, crystal microstructure, and oxidation state is of great importance to optimize their final use. However, while mature in understanding, it is still far from complete. Here we report on the effect of the amount of 1,2-hexadecanediol and/or 1-octadecene in the reaction mixture on the thermal decomposition of iron(III) acetylacetonate in oleic acid for two series of iron oxide NPs with sizes ranging from 6 to 48 nm. We show that a low amount of either compound leads to both large, mixed-phase NPs composed of magnetite (Fe3O4) and wüstite (FeO) and high reaction yields. In contrast, a higher amount of either 1,2-hexadecanediol or 1-octadecene gives rise to smaller, single-phase NPs with moderate reaction yields. By infrared spectroscopy, we have elucidated the role of 1,2-hexadecanediol, which mediates the particle nucleation and growth. Finally, we have correlated the magnetic response and the structural features of the NPs for the two series of samples.

9.
BMC Genomics ; 21(1): 336, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32357832

RESUMO

BACKGROUND: Norway spruce trees in subalpine forests frequently face infections by the needle rust fungus Chrysomyxa rhododendri, which causes significant growth decline and increased mortality of young trees. Yet, it is unknown whether trees actively respond to fungal attack by activating molecular defence responses and/or respective gene expression. RESULTS: Here, we report results from an infection experiment, in which the transcriptomes (via RNA-Seq analysis) and phenolic profiles (via UHPLC-MS) of control and infected trees were compared over a period of 39 days. Gene expression between infected and uninfected ramets significantly differed after 21 days of infection and revealed already known, but also novel candidate genes involved in spruce molecular defence against pathogens. CONCLUSIONS: Combined RNA-Seq and biochemical data suggest that Norway spruce response to infection by C. rhododendri is restricted locally and primarily activated between 9 and 21 days after infestation, involving a potential isolation of the fungus by a hypersensitive response (HR) associated with an activation of phenolic pathways. Identified key regulatory genes represent a solid basis for further specific analyses in spruce varieties with varying susceptibility, to better characterise resistant clones and to elucidate the resistance mechanism.


Assuntos
Basidiomycota/fisiologia , Picea/microbiologia , Doenças das Plantas/microbiologia , Imunidade Vegetal/genética , Regulação da Expressão Gênica de Plantas , Genes de Plantas/genética , Genoma de Planta/genética , Interações Hospedeiro-Patógeno , Redes e Vias Metabólicas , Fenóis/química , Fenóis/metabolismo , Picea/genética , Picea/metabolismo , Doenças das Plantas/genética , RNA-Seq , Metabolismo Secundário , Transdução de Sinais , Transcriptoma
10.
Mikrochim Acta ; 187(9): 488, 2020 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-32761453

RESUMO

The selection and comparative study is reported of calibration curves to quantify iron by a simple UV-Vis protocol based on the formation of iron (III) chloride complexes. The reliability of each calibration curve was evaluated using statistical and analytical parameters. The robustness of each calibration curve using superparamagnetic iron oxide nanoparticles (SPIONs) of different sizes and surface functionalization is demonstrated . We have also evaluated the effect of the particle coating and estimated the minimum time to ensure the full oxidation of iron (II) to (III) in sample solutions. Results from UV-Vis are comparable with those obtained from ICP-OES and from other spectroscopic techniques to quantify the iron. We advocate the proposed protocol as a simple and non-expensive route to determine accurately the iron content in colloidal and nanocomposite iron-based materials. Graphical abstract.

12.
Plant Mol Biol ; 94(3): 229-251, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28190131

RESUMO

KEY MESSAGE: Accumulation of phenolic needle metabolites in Norway spruce is regulated by many genes with small and additive effects and is correlated with the susceptibility against fungal attack. Norway spruce accumulates high foliar concentrations of secondary phenolic metabolites, with important functions for pathogen defence responses. However, the molecular genetic basis underlying the quantitative variation of phenolic compounds and their role in enhanced resistance of spruce to infection by needle bladder rust are unknown. To address these questions, a set of 1035 genome-wide single nucleotide polymorphisms (SNPs) was associated to the quantitative variation of four simple phenylpropanoids, eight stilbenes, nine flavonoids, six related arithmetic parameters and the susceptibility to infection by Chrysomyxa rhododendri in an unstructured natural population of Norway spruce. Thirty-one significant genetic associations for the flavonoids gallocatechin, kaempferol 3-glucoside and quercetin 3-glucoside and the stilbenes resveratrol, piceatannol, astringin and isorhapontin were discovered, explaining 22-59% of phenotypic variation, and indicating a regulation of phenolic accumulation by many genes with small and additive effects. The phenolics profile differed between trees with high and low susceptibility to the fungus, underlining the importance of phenolic compounds in the defence mechanisms of Norway spruce to C. rhododendri. Results highlight the utility of association studies in non-model tree species and may enable marker-assisted selection of Norway spruce adapted to severe pathogen attack.


Assuntos
Fenóis/metabolismo , Picea/genética , Picea/fisiologia , Doenças das Plantas/microbiologia , Folhas de Planta/metabolismo , Áustria , Basidiomycota , Análise por Conglomerados , Demografia , Marcadores Genéticos , Predisposição Genética para Doença , Genótipo , Fenóis/química , Picea/química , Doenças das Plantas/genética , Folhas de Planta/química , Polimorfismo de Nucleotídeo Único
13.
Phys Chem Chem Phys ; 17(41): 27373-9, 2015 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-26419530

RESUMO

This work reports on the effect of the oleic acid concentration on the magnetic and structural properties of Fe3-xO4 nanoparticles synthesized by thermal decomposition of Fe(acac)3 in benzyl-ether. This method allows the synthesis of highly monodisperse particles ranging from 7 to 100 nm in size by only varying the concentration of oleic acid in the reaction mixture. The structural and magnetic characterization reveal homogeneous particles in composition, with narrow particle size distribution, which are single-phase magnetite with almost bulk-like values of the saturation magnetization of about 90-99 emu g(-1) at low temperatures and show the characteristic anomaly in the zero field-cooling magnetization curves associated with the Verwey transition for nanoparticles bigger than about 7 nm. In addition, the analyses of aliquots of the reaction mixtures by Fourier transform infrared spectroscopy at various stages shed light on the nucleation and growth processes of the particles.

14.
Phys Chem Chem Phys ; 17(19): 13143-9, 2015 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-25917308

RESUMO

This work reports on the effect of the 1,2-hexadecanediol content on the structural and magnetic properties of CoFe2O4 nanoparticles synthesized by thermal decomposition of metal-organic precursors in 1-octadecene. Although pseudo-spherical particles having an average size of about 8 nm and similar stoichiometry have been observed in all studied samples, a high level of variability in the crystal quality and, in turn, in the magnetic properties has been found as a function of the amount of 1,2-hexadecanediol added to the reaction mixture. The magnetic study reveals that samples progress from glassy magnetic behavior to bulk-like, ferrimagnetic order as the crystal quality improves. The analysis of the reaction mixtures by Fourier transform infrared spectroscopy at various stages of the reaction shows the key role of the 1,2-hexadecanediol in favoring the decomposition of the metal-organic precursor, formation of an intermediate Co(2+)Fe(3+)-oleate complex and, finally, the nucleation of nanoparticles at lower temperatures.

15.
Genet Mol Biol ; 37(1): 105-10, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24688297

RESUMO

There is considerable controversy with regard to the genotoxicity of glyphosate, with some reports stating that this compound is non-toxic for fish, birds and mammals. In this work, we used the comet assay to examine the genotoxicity of glyphosate isopropylamine (0.7, 7, 70 and 700 µM) in human lymphocytes, erythrocytes of Oreochromis niloticus and staminal nuclei of Tradescantia (4430) in vitro and in vivo. Cells, nuclei and fish that had and had not been exposed to 5 mM N-nitrosodiethylamine (NDEA) were used as positive and negative controls, respectively. Significant (p < 0.01) genetic damage was observed in vivo and in vitro in all cell types and organisms tested. Human lymphocytes and Tradescantia hairs showed lower genetic damage in vivo compared to in vitro, possibly because of efficient metabolization of the herbicide. In O. niloticus erythrocytes, significant (p < 0.001) genotoxicity was observed at ≥ 7 µM, whereas in vitro, glyphosphate was genotoxic in human lymphocytes and Tradescantia hairs at ≥ 0.7 µM. These results indicate that glyphosate is genotoxic in the cells and organisms studied at concentrations of 0.7-7 µM.

16.
Nanoscale ; 16(4): 1942-1951, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38170857

RESUMO

Iron oxide nanoflowers (IONF) are densely packed multi-core aggregates known for their high saturation magnetization and initial susceptibility, as well as low remanence and coercive field. This study reports on how the local magnetic texture originating at the crystalline correlations among the cores determines the special magnetic properties of individual IONF over a wide size range from 40 to 400 nm. Regardless of this significant size variation in the aggregates, all samples exhibit a consistent crystalline correlation that extends well beyond the IONF cores. Furthermore, a nearly zero remnant magnetization, together with the presence of a persistently blocked state, and almost temperature-independent field-cooled magnetization, support the existence of a 3D magnetic texture throughout the IONF. This is confirmed by magnetic transmission X-ray microscopy images of tens of individual IONF, showing, in all cases, a nearly demagnetized state caused by the vorticity of the magnetic texture. Micromagnetic simulations agree well with these experimental findings, showing that the interplay between the inter-core direct exchange coupling and the demagnetizing field is responsible for the highly vortex-like spin configuration that stabilizes at low magnetic fields and appears to have partial topological protection. Overall, this comprehensive study provides valuable insights into the impact of crystalline texture on the magnetic properties of IONF over a wide size range, offering a deeper understanding of their potential applications in fields such as biomedicine and water remediation.

17.
Rheumatol Int ; 33(1): 173-7, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22274131

RESUMO

To assess the inter- and intra-observer reproducibility of musculoskeletal ultrasonography among rheumatologist in detecting inflammatory and morphostructural changes in small joints of the hands in patients with rheumatoid arthritis (RA). Five members of the "Escuela de Ecografía del Colegio Mexicano de Reumatología" tested their inter- and intra-observer reliabilities in the assessment of basic sonographic findings of joint inflammation and bone erosion. Their results were compared to those obtained by a group of international experts from European League Against Rheumatism. A clinical rheumatologist evaluated eight RA patients. Five Siemens Acuson Antares ultrasound machines (7-13 MHz linear probes) were used. The OMERACT preliminary definitions of joint effusion, synovial hypertrophy, bone erosions and tenosynovitis were adopted. Inter-observer and intra-observer agreement was calculated by overall agreement and kappa statistics. Mean kappa value for joint effusion was good, 0.654 (85%); synovial hypertrophy, 0.550 (77.2%); power Doppler signal, 0.550 (82.5%); bone erosions, 0.549 (81%); and tenosynovitis, 0.500 (91.5%). Mean and overall intra-observer agreement for semiquantitative score was good for joint effusion, 0.630 (77.2%) and bone erosions, 0.605 (56.25%); and moderate to synovial hypertrophy, 0.476 (65%) and power Doppler signal, 0.471 (80%). Mean kappa value for joint effusion was 0.381 (95%), synovial hypertrophy, 0.447 (72%); power Doppler signal, 0.496 (81%); bone erosions, 0.294 (81%); and tenosynovitis, 0.030 (66%). Mean and overall inter-observer agreement for semiquantitative score was poor for joint effusion, 0.325 (57%) and bone erosions, 0.360 (43%); and moderate to synovial hypertrophy, 0.431 (55%) and power Doppler signal, 0.496 (81%). Intra-observer variability reached the highest levels of agreement. Factors related to the experience of the rheumatologist, the time spent in each examination and knowledge of the software ultrasound equipment could influence the lower level of inter-observer agreement in this study.


Assuntos
Artrite Reumatoide/diagnóstico por imagem , Articulação da Mão/diagnóstico por imagem , Articulação da Mão/patologia , Sinovite/diagnóstico por imagem , Ultrassonografia Doppler/métodos , Adulto , Idoso , Artrite Reumatoide/complicações , Artrite Reumatoide/fisiopatologia , Feminino , Articulação da Mão/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Sinovite/etiologia , Sinovite/fisiopatologia
18.
ACS Nano ; 16(11): 19253-19260, 2022 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-36315462

RESUMO

Magnetic nanoparticles (MNPs) are instrumental for fabrication of tailored nanomagnetic structures, especially where top-down lithographic patterning is not feasible. Here, we demonstrate precise and controllable manipulation of individual magnetite MNPs using the tip of an atomic force microscope. We verify our approach by placing a single MNP with a diameter of 50 nm on top of a 100 nm Hall bar fabricated in a quasi-two-dimensional electron gas (q2DEG) at the oxide interface between LaAlO3 and SrTiO3 (LAO/STO). A hysteresis loop due to the magnetic hysteresis properties of the magnetite MNPs was observed in the Hall resistance. Further, the effective coercivity of the Hall resistance hysteresis loop could be changed upon field cooling at different angles of the cooling field with respect to the measuring field. The effect is associated with the alignment of the MNP magnetic moment along the easy axis closest to the external field direction across the Verwey transition in magnetite. Our results can facilitate experimental realization of magnetic proximity devices using single MNPs and two-dimensional materials for spin-based nanoelectronics.

19.
Genes (Basel) ; 13(4)2022 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-35456415

RESUMO

Genes related to DNA damage repair in Mycobacterium tuberculosis are critical for survival and genomic diversification. The aim of this study is to compare the presence of SNPs in genes related to DNA damage repair in sensitive and drug-resistant M. tuberculosis genomes isolated from patients with and without type 2 diabetes mellitus (T2DM). We collected 399 M. tuberculosis L4 genomes from several public repositories; 224 genomes belonging to hosts without T2DM, of which 123 (54.9%) had drug sensitive tuberculosis (TB) and 101 (45.1%) had drug resistance (DR)-TB; and 175 genomes from individuals with T2DM, of which 100 (57.1%) had drug sensitive TB and 75 (42.9%) had DR-TB. The presence of SNPs in the coding regions of 65 genes related to DNA damage repair was analyzed and compared with the resistance profile and the presence/absence of T2DM in the host. The results show the phylogenetic relationships of some SNPS and L4 sub-lineages, as well as differences in the distribution of SNPs present in DNA damage repair-related genes related to the resistance profile of the infecting strain and the presence of T2DM in the host. Given these differences, it was possible to generate two discriminant functions to distinguish between drug sensitive and drug resistant genomes, as well as patients with or without T2DM.


Assuntos
Diabetes Mellitus Tipo 2 , Mycobacterium tuberculosis , Tuberculose Resistente a Múltiplos Medicamentos , Tuberculose , Dano ao DNA/genética , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/genética , Resistência a Medicamentos , Humanos , Mycobacterium tuberculosis/genética , Filogenia , Polimorfismo de Nucleotídeo Único , Tuberculose/tratamento farmacológico , Tuberculose/genética , Tuberculose/microbiologia , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia
20.
Perit Dial Int ; 42(5): 535-539, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35352596

RESUMO

The Covid-19 pandemic has been responsible for millions of deaths worldwide. Patients with comorbidities- such as those on peritoneal dialysis (PD)- present higher morbidity and mortality than the general population. We prospectively evaluated all Chilean patients on PD (48 centres) and followed those who had Covid-19 from the beginning of the Covid-19 pandemic in Chile (March 2020) to January 2021 (start of vaccination campaign). We described demographic history, comorbidities, factors related to infection, need for hospitalisation and death due to Covid-19. During the study period, 106 adults on PD were infected by SARS-CoV-2, with a mean age of 53.1 (±16.3) and of which 53.9% were female. From that group, 54.8% required hospitalisation and 24.5% (n = 26) died due to Covid-19. Most of the patients (63.4%) were infected at home and 22.8% during hospitalisation for other reasons. There was a significant association for Covid-19 mortality with: being ≥60 years old, diabetes, time on PD ≥5 years, need for hospitalisation and hospital-acquired infection. At 90 days of follow-up, all deaths associated to Covid-19 occurred before 40 days. We conclude that patients on PD without Covid-19 vaccination have a high mortality and need for hospitalisation associated to Covid-19. To avoid this negative outcome, it is necessary to intensify strategies to avoid contagion, especially in those ≥60 years old, with diabetes and/or ≥5 years spent on PD.


Assuntos
COVID-19 , Diabetes Mellitus , Diálise Peritoneal , Adulto , COVID-19/terapia , Vacinas contra COVID-19 , Chile/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias , SARS-CoV-2
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