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1.
Nanoscale ; 16(4): 1942-1951, 2024 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-38170857

RESUMEN

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.

2.
Molecules ; 28(12)2023 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-37375274

RESUMEN

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.


Asunto(s)
Lamiaceae , Aceites Volátiles , Satureja , Antioxidantes/farmacología , Antioxidantes/química , Aceites Volátiles/farmacología , Aceites Volátiles/química , Satureja/química , Escherichia coli , Staphylococcus aureus , Antibacterianos/farmacología , Antibacterianos/química , Lamiaceae/química , Aceites de Plantas/química
3.
Int J Mol Sci ; 24(5)2023 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-36901992

RESUMEN

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.


Asunto(s)
Herbicidas , Humanos , Ensayo Cometa , Células Sanguíneas , Glicina , Adyuvantes Inmunológicos , Adyuvantes Farmacéuticos , Glifosato
4.
Phys Chem Chem Phys ; 25(5): 3900-3911, 2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36648114

RESUMEN

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.

5.
ACS Nano ; 16(11): 19253-19260, 2022 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-36315462

RESUMEN

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.

6.
Microb Genom ; 8(7)2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35787782

RESUMEN

Genomic studies of the Mycobacterium tuberculosis complex (MTBC) might shed light on the dynamics of its transmission, especially in high-burden settings, where recent outbreaks are embedded in the complex natural history of the disease. To this end, we conducted a 1 year prospective surveillance-based study in Mozambique. We applied whole-genome sequencing (WGS) to 295 positive cultures. We fully characterized MTBC isolates by phylogenetics and dating evaluation, and carried out a molecular epidemiology analysis to investigate further associations with pre-defined transmission risk factors. The majority of strains (49.5%, 136/275) belonged to lineage (L) 4; 57.8 % of them (159/275) were in genomic transmission clusters (cut-off 5 SNPs), and a strikingly high proportion (45.5%) shared an identical genotype (0 SNP pairwise distance). We found two 'likely endemic' clades, comprising 67 strains, belonging to L1.2, which dated back to the late 19th century and were associated with recent spread among people living with human immunodeficiency virus (PLHIV). We describe for the first time the population structure of MTBC in our region, a high tuberculosis (TB)/HIV burden area. Clustering analysis revealed an unforeseen pattern of spread and high rates of progression to active TB, suggesting weaknesses in TB control activities. The long-term presence of local strains in Mozambique, which were responsible for large transmission among HIV/TB-coinfected patients, calls into question the role of HIV in TB transmission.


Asunto(s)
Infecciones por VIH , Mycobacterium tuberculosis , Tuberculosis , Infecciones por VIH/epidemiología , Humanos , Mozambique/epidemiología , Mycobacterium tuberculosis/genética , Estudios Prospectivos , Tuberculosis/epidemiología
7.
Curr Issues Mol Biol ; 44(5): 2230-2242, 2022 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-35678680

RESUMEN

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.

8.
Molecules ; 27(12)2022 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-35744920

RESUMEN

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.


Asunto(s)
Magnetismo , Robótica , Campos Magnéticos
9.
BMC Genomics ; 23(1): 435, 2022 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-35692040

RESUMEN

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.


Asunto(s)
Picea , Perfilación de la Expresión Génica , Inmunidad Innata , Picea/microbiología , Enfermedades de las Plantas/genética , Enfermedades de las Plantas/microbiología , Árboles/genética , Vejiga Urinaria
10.
BMC Genomics ; 23(1): 465, 2022 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-35751020

RESUMEN

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.


Asunto(s)
Diabetes Mellitus Tipo 2 , Mycobacterium tuberculosis , Tuberculosis Resistente a Múltiples Medicamentos , Tuberculosis , Antituberculosos/farmacología , Antituberculosos/uso terapéutico , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Diabetes Mellitus Tipo 2/genética , Farmacorresistencia Bacteriana Múltiple/genética , Humanos , Pruebas de Sensibilidad Microbiana , Filogenia , Polimorfismo de Nucleótido Simple , Rifampin/uso terapéutico , Tuberculosis/tratamiento farmacológico , Tuberculosis/epidemiología , Tuberculosis/genética , Tuberculosis Resistente a Múltiples Medicamentos/tratamiento farmacológico , Tuberculosis Resistente a Múltiples Medicamentos/genética , Secuenciación Completa del Genoma
11.
Genes (Basel) ; 13(4)2022 03 29.
Artículo en Inglés | MEDLINE | ID: mdl-35456415

RESUMEN

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.


Asunto(s)
Diabetes Mellitus Tipo 2 , Mycobacterium tuberculosis , Tuberculosis Resistente a Múltiples Medicamentos , Tuberculosis , Daño del ADN/genética , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Diabetes Mellitus Tipo 2/genética , Resistencia a Medicamentos , Humanos , Mycobacterium tuberculosis/genética , Filogenia , Polimorfismo de Nucleótido Simple , Tuberculosis/tratamiento farmacológico , Tuberculosis/genética , Tuberculosis/microbiología , Tuberculosis Resistente a Múltiples Medicamentos/microbiología
12.
Perit Dial Int ; 42(5): 535-539, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35352596

RESUMEN

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.


Asunto(s)
COVID-19 , Diabetes Mellitus , Diálisis Peritoneal , Adulto , COVID-19/terapia , Vacunas contra la COVID-19 , Chile/epidemiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pandemias , SARS-CoV-2
13.
Medicentro (Villa Clara) ; 26(1)mar. 2022.
Artículo en Español | LILACS | ID: biblio-1405622

RESUMEN

RESUMEN El nuevo coronavirus SARS-CoV-2 que provoca la COVID-19, por su rápida propagación y el gran número de casos positivos y de fallecidos, fue declarado por la Organización Mundial de la Salud, el 11 de marzo de 2020, como pandemia, fecha que coincide con los primeros casos diagnosticados en Cuba. En esta investigación se describe la efectividad de la metodología de capacitación para prevenir la COVID-19 en centros laborales. Se realizó una investigación de intervención-acción y se utilizó la audiencia sanitaria para desarrollar los temas de bioseguridad. Participaron 511 trabajadores de 11 centros laborales; se monitoreó la efectividad que había tenido esta capacitación. Se seleccionaron dos centros laborales como centros pilotos, donde se aplicaron encuestas a sus trabajadores para comprobar el cumplimiento de las medidas de bioseguridad orientadas. Se demostró que con la adecuada capacitación se puede prevenir y controlar la propagación de esta mortal enfermedad en centros laborales.


ABSTRACT The new SARS-CoV-2 coronavirus that causes COVID-19 was declared a pandemic by the World Health Organization on 11 March 2020 due to its rapid spread and the large number of positive cases and deaths; coinciding this date with the first cases diagnosed in Cuba. This research describes the effectiveness of a training methodology to prevent COVID-19 in workplaces. An intervention-action research was carried out using the health audience to develop biosafety topics. A total of 511 workers from 11 workplaces participated; the effectiveness of the training methodology was monitored. Two workplaces were selected as pilot sites, where workers were surveyed to check their compliance with the targeted biosecurity measures. It was demonstrated that the spread of this deadly disease can be prevented and controlled in workplaces with the proper training.


Asunto(s)
Educación en Salud , COVID-19/prevención & control
14.
Trends psychiatry psychother. (Impr.) ; 43(3): 185-192, Jul.-Sept. 2021. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1361176

RESUMEN

Abstract Objective To evaluate the role of social support in the association between physical activity (PA) in its various domains and depressive symptoms in older adults. Methods This was a cross-sectional study involving 399 older adults seen at basic health units in the municipality of Recife, state of Pernambuco, northeastern Brazil. Linear regression was implemented using the forward method to assess the association between PA and its domains and depressive symptoms, as well as to test the possible moderating component of social support in this association. Results Of the total sample, 17.6% reported not practicing PA; 6.7% presented depressive symptoms, with a mean score of 1.59 points. A total of 18.6% of the older adults assessed reported not having social support. Older adults who did not practice total, transportation or domestic PA showed increased scores of depressive symptoms when compared to older adults who practiced PA in these domains. Older adults with social support also had fewer depressive symptoms. Practicing domestic, leisure and total PA, and/or having social support, decreased depressive symptoms in older adults. Having social support or practicing PA decreased depressive symptoms in older adults in a similar way. Conclusions Older adults with social support and who practiced PA, especially domestic and total PA, presented the lowest scores of depressive symptoms. The data showed the importance of providing elements to strengthen social support and PA practice in older adults living in poor communities as a strategy to prevent and reduce depressive symptoms.

15.
Artículo en Inglés | MEDLINE | ID: mdl-33605373

RESUMEN

OBJECTIVE: To evaluate the role of social support in the association between physical activity (PA) in its various domains and depressive symptoms in older adults. METHODS: This was a cross-sectional study involving 399 older adults seen at basic health units in the municipality of Recife, state of Pernambuco, northeastern Brazil. Linear regression was implemented using the forward method to assess the association between PA and its domains and depressive symptoms, as well as to test the possible moderating component of social support in this association. RESULTS: Of the total sample, 17.6% reported not practicing PA; 6.7% presented depressive symptoms, with a mean score of 1.59 points. A total of 18.6% of the older adults assessed reported not having social support. Older adults who did not practice total, transportation or domestic PA showed increased scores of depressive symptoms when compared to older adults who practiced PA in these domains. Older adults with social support also had fewer depressive symptoms. Practicing domestic, leisure and total PA, and/or having social support, decreased depressive symptoms in older adults. Having social support or practicing PA decreased depressive symptoms in older adults in a similar way. CONCLUSIONS: Older adults with social support and who practiced PA, especially domestic and total PA, presented the lowest scores of depressive symptoms. The data showed the importance of providing elements to strengthen social support and PA practice in older adults living in poor communities as a strategy to prevent and reduce depressive symptoms.

16.
Sci Rep ; 11(1): 1870, 2021 01 21.
Artículo en Inglés | MEDLINE | ID: mdl-33479318

RESUMEN

Whole genome sequencing (WGS) has been shown to be superior to traditional procedures of genotyping in tuberculosis (TB), nevertheless, reports of its use in drug resistant TB (DR-TB) isolates circulating in Mexico, are practically unknown. Considering the above the main of this work was to identify and characterize the lineages and genomic transmission clusters present in 67 DR-TB isolates circulating in southeastern Mexico. The results show the presence of three major lineages: L1 (3%), L2 (3%) and L4 (94%), the last one included 16 sublineages. Sublineage 4.1.1.3 (X3) was predominant in 18 (27%) of the isolates, including one genomic cluster, formed by eleven multidrug resistant isolates and sharing the SIT 3278, which seems to be restricted to Mexico. By the use of WGS, it was possible to identify the high prevalence of L4 and a high number of sublineages circulating in the region, also was recognized the presence of a novel X3 sublineage, formed exclusively by multidrug resistant isolates and with restrictive circulation in Mexico for at least the past 17 years.


Asunto(s)
Farmacorresistencia Bacteriana Múltiple/genética , Técnicas de Genotipaje/métodos , Mycobacterium tuberculosis/genética , Secuenciación Completa del Genoma/métodos , Adulto , Antituberculosos/farmacología , Estudios Transversales , ADN Bacteriano/química , ADN Bacteriano/genética , Farmacorresistencia Bacteriana Múltiple/efectos de los fármacos , Femenino , Genómica/métodos , Genotipo , Humanos , Masculino , México , Persona de Mediana Edad , Familia de Multigenes/genética , Mycobacterium tuberculosis/efectos de los fármacos , Mycobacterium tuberculosis/fisiología , Filogenia , Polimorfismo de Nucleótido Simple , Tuberculosis Resistente a Múltiples Medicamentos/tratamiento farmacológico , Tuberculosis Resistente a Múltiples Medicamentos/microbiología
17.
Langmuir ; 37(1): 35-45, 2021 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-33301314

RESUMEN

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.

18.
Mikrochim Acta ; 187(9): 488, 2020 08 06.
Artículo en Inglés | MEDLINE | ID: mdl-32761453

RESUMEN

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.

19.
BMC Genomics ; 21(1): 336, 2020 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-32357832

RESUMEN

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.


Asunto(s)
Basidiomycota/fisiología , Picea/microbiología , Enfermedades de las Plantas/microbiología , Inmunidad de la Planta/genética , Regulación de la Expresión Génica de las Plantas , Genes de Plantas/genética , Genoma de Planta/genética , Interacciones Huésped-Patógeno , Redes y Vías Metabólicas , Fenoles/química , Fenoles/metabolismo , Picea/genética , Picea/metabolismo , Enfermedades de las Plantas/genética , RNA-Seq , Metabolismo Secundario , Transducción de Señal , Transcriptoma
20.
Microb Drug Resist ; 26(7): 732-740, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31874045

RESUMEN

Whole genome sequencing (WGS) has been proposed as a tool for the diagnosis of drug resistance in tuberculosis (TB); however, there have been few studies on its effectiveness in countries with significantly high drug resistance rates. This study therefore aimed to evaluate the effectiveness of WGS to identify mutations related to drug resistance in TB isolates from an endemic region of Mexico. The results showed that, of 35 multidrug-resistant isolates analyzed, the values of congruence found between the phenotypic drug susceptibility testing and polymorphisms were 94% for isoniazid, 97% for rifampicin, 90% for ethambutol, and 82% for pyrazinamide. It was also possible to identify eight isolates as potential pre-extensive drug resistant (XDR) and one as XDR. Twenty nine isolates were classified within L4 and two transmission clusters were identified. The results show the potential utility of WGS for predicting resistance against first- and second-line drugs, as well as providing a phylogenetic characterization of TB drug-resistant isolates circulating in Mexico.


Asunto(s)
Antituberculosos/farmacología , Mycobacterium tuberculosis/efectos de los fármacos , Mycobacterium tuberculosis/genética , Tuberculosis Resistente a Múltiples Medicamentos/genética , Tuberculosis Extensivamente Resistente a Drogas/genética , Humanos , México/epidemiología , Pruebas de Sensibilidad Microbiana , Fenotipo , Polimorfismo Genético , Secuenciación Completa del Genoma
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