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1.
Curr Microbiol ; 81(7): 173, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38750329

RESUMEN

The ability of fungi to effectively sense and internalize signals related to extracellular changing environments is essential for survival. This adaptability is particularly important for fungal pathogens of humans and plants that must sense and respond to drastic environmental changes when colonizing their hosts. One of the most important physicochemical factors affecting fungal growth and development is the pH. Ascomycota fungal species possess mechanisms such as the Pal/Rim pathway for external pH sensing and adaptation. However, the conservation of this mechanism in other fungi, such as Ustilaginomycetes is still little studied. To overcome this knowledge gap, we used a comparative genomic approach to explore the conservation of the Pal/Rim pathway in the 13 best sequenced and annotated Ustilaginomycetes. Our findings reveal that the Rim proteins and the Endosomal Sorting Complex Required for Transport (ESCRT) proteins are conserved in Ustilaginomycetes. They conserve the canonical domains present in Pal/Rim and ESCRT proteins of Ascomycota. This study sheds light on the molecular mechanisms used by these fungi for responding to extracellular stresses such as the pH, and open the door to further experimentations for understanding the molecular bases of the signaling in Ustilaginomycetes.


Asunto(s)
Proteínas Fúngicas , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Concentración de Iones de Hidrógeno , Transducción de Señal , Ascomicetos/genética , Ascomicetos/metabolismo , Complejos de Clasificación Endosomal Requeridos para el Transporte/metabolismo , Complejos de Clasificación Endosomal Requeridos para el Transporte/genética , Filogenia
2.
Gene ; : 148589, 2024 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-38777108

RESUMEN

Nitrogen is the principal nutrient deficiency that increases lipids and carbohydrate content in diatoms but negatively affects biomass production. Marine diatom Chaetoceros muelleri is characterized by lipid and carbohydrate accumulation under low nitrogen concentration without affecting biomass. To elucidate the molecular effects of nitrogen concentrations, we performed an RNA-seq analysis of C. muelleri grown under four nitrogen concentrations (3.53 mM, 1.76 mM, 0.44 mM, and 0.18 mM of NaNO3). This research revealed that changes in global transcription in C. muelleri are differentially expressed by nitrogen concentration. "Energetic metabolism", "Carbohydrate metabolism" and "Lipid metabolism" pathways were identified as the most upregulated by N deficiency. Due to N limitation, alternative pathways to self-supply nitrogen employed by microalgal cells were identified. Additionally, nitrogen limitation decreased chlorophyll content and caused a greater response at the transcriptional level with a higher number of unigenes differentially expressed. By contrast, the highest N concentration (3.53 mM) recorded the lowest number of differentially expressed genes. Amt1, Nrt2, Fad2, Skn7, Wrky19, and Dgat2 genes were evaluated by RT-qPCR. In conclusion, C. muelleri modify their metabolic pathways to optimize nitrogen utilization and minimize nitrogen losses. On the other hand, the assembled transcriptome serves as the basis for metabolic engineering focused on improving the quantity and quality of the diatom for biotechnological applications. However, proteomic and metabolomic analysis is also required to compare gene expression, protein, and metabolite accumulation.

3.
Molecules ; 29(5)2024 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-38474512

RESUMEN

Quercetin is a flavonoid with a low molecular weight that belongs to the human diet's phenolic phytochemicals and nonenergy constituents. Quercetin has a potent antioxidant capacity, being able to capture reactive oxygen species (ROS), reactive nitrogen species (RNS), and reactive chlorine species (ROC), which act as reducing agents by chelating transition-metal ions. Its structure has five functional hydroxyl groups, which work as electron donors and are responsible for capturing free radicals. In addition to its antioxidant capacity, different pharmacological properties of quercetin have been described, such as carcinostatic properties; antiviral, antihypertensive, and anti-inflammatory properties; the ability to protect low-density lipoprotein (LDL) oxidation, and the ability to inhibit angiogenesis; these are developed in this review.


Asunto(s)
Flavonoides , Quercetina , Humanos , Quercetina/farmacología , Antioxidantes/química , Radicales Libres/química , Oxidación-Reducción , Especies Reactivas de Oxígeno
4.
Microbiology (Reading) ; 170(3)2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38456839

RESUMEN

Candida maltosa is closely related to important pathogenic Candida species, especially C. tropicalis and C. albicans, but it has been rarely isolated from humans. For this reason, through comparative studies, it could be a powerful model to understand the genetic underpinnings of the pathogenicity of Candida species. Here, we generated a cohesive assembly of the C. maltosa genome and developed genetic engineering tools that will facilitate studying this species at a molecular level. We used a combination of short and long-read sequencing to build a polished genomic draft composed of 14 Mbp, 45 contigs and close to 5700 genes. This assembly represents a substantial improvement from the currently available sequences that are composed of thousands of contigs. Genomic comparison with C. albicans and C. tropicalis revealed a substantial reduction in the total number of genes in C. maltosa. However, gene loss seems not to be associated to the avirulence of this species given that most genes that have been previously associated with pathogenicity were also present in C. maltosa. To be able to edit the genome of C. maltosa we generated a set of triple auxotrophic strains so that gene deletions can be performed similarly to what has been routinely done in pathogenic Candida species. As a proof of concept, we generated gene knockouts of EFG1, a gene that encodes a transcription factor that is essential for filamentation and biofilm formation in C. albicans and C. tropicalis. Characterization of these mutants showed that Efg1 also plays a role in biofilm formation and filamentous growth in C. maltosa, but it seems to be a repressor of filamentation in this species. The genome assembly and auxotrophic mutants developed here are a key step forward to start using C. maltosa for comparative and evolutionary studies at a molecular level.


Asunto(s)
Candida albicans , Candida , Humanos , Candida/genética , Candida albicans/genética , Candida tropicalis/genética , Evolución Biológica
6.
Prev Sci ; 2024 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-38244166

RESUMEN

Adolescent school connectedness generally protects from risk behaviors such as tobacco use; however, its relationship to e-cigarette use is unclear. This study examines the relationship between adolescent school connectedness and e-cigarette susceptibility in a diverse longitudinal sample. This secondary analysis of a school-based intervention surveyed 608 middle (66%) and high school (34%) students from 10 schools at 3 time points over 1 year. At baseline, respondents had a mean age of 14 years, 54% were female, and 71% were BIPOC (Black, Indigenous, People of Color). Logistic regression models examined unadjusted and adjusted associations between school connectedness (both baseline and concurrent) and e-cigarette susceptibility over time. E-cigarettes represented the most prevalent form of current nicotine-containing product use in spring 2019 (2.3%), and most respondents reported no e-cigarette susceptibility (69%). E-cigarette susceptibility remained relatively stable during the study. Higher baseline school connectedness levels were associated with lower odds of e-cigarette susceptibility over time. Similarly, higher concurrent school connectedness scores were associated with lower odds of e-cigarette susceptibility over time: spring 2019 (OR, 0.39; 95% CI, 0.32, 0.47), fall 2019 (OR, 0.49; 95% CI, 0.34, 0.72), and spring 2020 (OR, 0.64; 95% CI, 0.47, 0.87). Findings were similar for middle and high school students and did not differ significantly after adjusting for other covariates. Adolescents' school connectedness appears to protect from e-cigarette susceptibility over time, underscoring the importance of promoting positive school experiences to reduce adolescent risk e-cigarette use.

7.
Yeast ; 41(1-2): 35-51, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38054508

RESUMEN

Yeasts are a diverse group of fungal microorganisms that are widely used to produce fermented foods and beverages. In Mexico, open fermentations are used to obtain spirits from agave plants. Despite the prevalence of this traditional practice throughout the country, yeasts have only been isolated and studied from a limited number of distilleries. To systematically describe the diversity of yeast species from open agave fermentations, here we generate the YMX-1.0 culture collection by isolating 4524 strains from 68 sites with diverse climatic, geographical, and biological contexts. We used MALDI-TOF mass spectrometry for taxonomic classification and validated a subset of the strains by ITS and D1/D2 sequencing, which also revealed two potential novel species of Saccharomycetales. Overall, the composition of yeast communities was weakly associated with local variables and types of climate, yet a core set of six species was consistently isolated from most producing regions. To explore the intraspecific variation of the yeasts from agave fermentations, we sequenced the genomes of four isolates of the nonconventional yeast Kazachstania humilis. The genomes of these four strains were substantially distinct from a European isolate of the same species, suggesting that they may belong to different populations. Our work contributes to the understanding and conservation of an open fermentation system of great cultural and economic importance, providing a valuable resource to study the biology and genetic diversity of microorganisms living at the interface of natural and human-associated environments.


Asunto(s)
Agave , Humanos , Fermentación , Agave/microbiología , México , Levaduras , Bebidas Alcohólicas/microbiología
10.
Curr Issues Mol Biol ; 45(11): 8716-8732, 2023 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-37998725

RESUMEN

Type 2 diabetes (T2D) is a chronic systemic disease with a complex etiology, characterized by insulin resistance and mitochondrial dysfunction in various cell tissues. To explore this relationship, we conducted a secondary analysis of complete mtDNA sequences from 1261 T2D patients and 1105 control individuals. Our findings revealed significant associations between certain single-nucleotide polymorphisms (SNPs) and T2D. Notably, the variants m.1438A>G (rs2001030) (controls: 32 [27.6%], T2D: 84 [72.4%]; OR: 2.46; 95%CI: 1.64-3.78; p < 0.001), m.14766C>T (rs193302980) (controls: 498 [36.9%], T2D: 853 [63.1%]; OR: 2.57, 95%CI: 2.18-3.04, p < 0.001), and m.16519T>C (rs3937033) (controls: 363 [43.4%], T2D: 474 [56.6%]; OR: 1.24, 95%CI: 1.05-1.47, p = 0.012) were significantly associated with the likelihood of developing diabetes. The variant m.16189T>C (rs28693675), which has been previously documented in several studies across diverse populations, showed no association with T2D in our analysis (controls: 148 [13.39] T2D: 171 [13.56%]; OR: 1.03; 95%CI: 0.815-1.31; p = 0.83). These results provide evidence suggesting a link between specific mtDNA polymorphisms and T2D, possibly related to association rules, topological patterns, and three-dimensional conformations associated with regions where changes occur, rather than specific point mutations in the sequence.

11.
Front Plant Sci ; 14: 1257098, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37810383

RESUMEN

Microbial volatile organic compounds (MVOCs) are mixtures of gas-phase hydrophobic carbon-based molecules produced by microorganisms such as bacteria and fungi. They can act as airborne signals sensed by plants being crucial players in triggering signaling cascades influencing their secondary metabolism, development, and growth. The role of fungal volatile organic compounds (FVOCs) from beneficial or detrimental species to influence the physiology and priming effect of plants has been well studied. However, the plants mechanisms to discern between FVOCs from friend or foe remains significantly understudied. Under this outlook, we present an overview of the VOCs produced by plant-associate fungal species, with a particular focus on the challenges faced in VOCs research: i) understanding how plants could perceive FVOCs, ii) investigating the differential responses of plants to VOCs from beneficial or detrimental fungal strains, and finally, iii) exploring practical aspects related to the collection of VOCs and their eco-friendly application in agriculture.

12.
Int J Pharm ; 644: 123331, 2023 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-37597595

RESUMEN

Controlled-release formulations for pulmonary delivery are highly desirable for treating chronic diseases such as COPD. However, a limited number of polymers are currently approved for inhalation. The study presents a promising strategy using gelatin as a matrix for inhalable dry powders, allowing the controlled release of ionic drugs. Ionized cromoglicate sodium (CS) and ipratropium bromide (IBr) interacted in solution with charged gelatin before spray drying (SD). Calcium carbonate was used as a crosslinker. The microspheres showed remarkable aerosol performance after optimizing the SD parameters and did not cause cytotoxicity in A549 cells. The microspheres were highly dispersible with âˆ¼ 50-60% of respirable fraction and fine particle fraction 55-70%. Uncrosslinked microspheres increased their size from four to ten times by swelling after 5 min showing potential as a strategy to avoid macrophage clearance and prolong the therapeutic effect of the drug. Crosslinkers prevented particle swelling. Ionic interaction generated a moderate reduction of the drug release. Overall, this study provides a novel approach for developing DPI formulations for treating chronic respiratory diseases using a biopolymer approved by the FDA, potentially enhancing drug activity through controlled release and avoiding macrophage clearance.


Asunto(s)
Cromolin Sódico , Gelatina , Preparaciones de Acción Retardada , Ipratropio , Microesferas
13.
Health Hum Rights ; 25(1): 105-117, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37266318

RESUMEN

Global health equity is at a historically tenuous nexus complicated by economic inequality, climate change, mass migration, racialized violence, and global pandemics. Social medicine, collective health, and structural competency are interdisciplinary fields with their own histories and fragmentary implementation in health equity movements situated both locally and globally. In this paper, we review these three fields' historical backgrounds, theoretical underpinnings, and contemporary contributions to global health equity. We believe that intentional dialogue between these fields could promote a generative discourse rooted in a shared understanding of their historical antecedents and theoretical frameworks. We also propose pedagogical tools grounded within our own critical and transformative pedagogies that offer the prospect of bringing these traditions into greater dialogue for the purpose of actualizing the human right to health.


Asunto(s)
Equidad en Salud , Medicina Social , Humanos , Derechos Humanos , Violencia , Cambio Climático
16.
Genome Biol ; 24(1): 59, 2023 03 29.
Artículo en Inglés | MEDLINE | ID: mdl-36991492

RESUMEN

BACKGROUND: Genome-wide association studies (GWAS) have identified > 200 loci associated with breast cancer risk. The majority of candidate causal variants are in non-coding regions and likely modulate cancer risk by regulating gene expression. However, pinpointing the exact target of the association, and identifying the phenotype it mediates, is a major challenge in the interpretation and translation of GWAS. RESULTS: Here, we show that pooled CRISPR screens are highly effective at identifying GWAS target genes and defining the cancer phenotypes they mediate. Following CRISPR mediated gene activation or suppression, we measure proliferation in 2D, 3D, and in immune-deficient mice, as well as the effect on DNA repair. We perform 60 CRISPR screens and identify 20 genes predicted with high confidence to be GWAS targets that promote cancer by driving proliferation or modulating the DNA damage response in breast cells. We validate the regulation of a subset of these genes by breast cancer risk variants. CONCLUSIONS: We demonstrate that phenotypic CRISPR screens can accurately pinpoint the gene target of a risk locus. In addition to defining gene targets of risk loci associated with increased breast cancer risk, we provide a platform for identifying gene targets and phenotypes mediated by risk variants.


Asunto(s)
Estudio de Asociación del Genoma Completo , Neoplasias , Animales , Ratones , Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas , Predisposición Genética a la Enfermedad , Fenotipo , Polimorfismo de Nucleótido Simple
17.
Adv Mater ; : e2209950, 2023 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-37001880

RESUMEN

Integrating photovoltaic devices onto the surface of carbon-fiber-reinforced polymer substrates should create materials with high mechanical strength that are also able to generate electrical power. Such devices are anticipated to find ready applications as structural, energy-harvesting systems in both the automotive and aeronautical sectors. Here, the fabrication of triple-cation perovskite n-i-p solar cells onto the surface of planarized carbon-fiber-reinforced polymer substrates is demonstrated, with devices utilizing a transparent top ITO contact. These devices also contain a "wrinkled" SiO2 interlayer placed between the device and substrate that alleviates thermally induced cracking of the bottom ITO layer. Devices are found to have a maximum stabilized power conversion efficiency of 14.5% and a specific power (power per weight) of 21.4 W g-1 (without encapsulation), making them highly suitable for mobile power applications.

18.
Healthc Inform Res ; 29(1): 4-15, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36792096

RESUMEN

OBJECTIVES: This paper presents a systematic mapping of studies related to information systems and technology in the field of healthcare, enabling a visual mapping of the different lines of knowledge that can provide an overview of the scientific literature in this field. This map can help to clarify critical aspects of healthcare informatics, such as the main types of information systems, the ways in which they integrate with each other, and the technological trends in this field. METHODS: Systematic mapping refers to a process of classifying information in a given area of knowledge. It provides an overview of the state of the art in a particular discipline or area of knowledge, establishing a map that describes how knowledge is structured in that particular area. In this study, we proposed and carried out a specific implementation of the methodology for mapping. In total, 1,619 studies that combine knowledge related to information systems, computer science, and healthcare were selected and compiled from prestigious publications. RESULTS: The results established a distribution of the available literature and identified papers related to certain research questions, thereby providing a map of knowledge that structures the different trends and main areas of research, making it possible to address the research questions and serving as a guide to deepen specific aspects of the field of study. CONCLUSIONS: We project and propose future research for the trends that stand out because of their interest and the possibility of exploring these topics in greater depth.

19.
Opt Lett ; 48(3): 712-714, 2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36723570

RESUMEN

We have demonstrated a record-high 1.2 kW, all-fiber multicore amplifier using a six-core single-mode Yb-doped fiber and a multicore pump-signal combiner (PSC). The output power is limited by the pump power of 1.9 kW. We have developed double-clad six-core fibers and PSCs for this demonstration. Each of the six Yb-doped cores has a 17-µm mode-field diameter (MFD) with a trench index profile and is capable of kW-class operation. The potential power scaling to the 10-kW level in a single amplifier with high brightness should be feasible with advanced thermal management and coherent beam combination.

20.
Molecules ; 28(2)2023 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-36677659

RESUMEN

A wound is the loss of the normal integrity, structure, and functions of the skin due to a physical, chemical, or mechanical agent. Wound repair consists of an orderly and complex process divided into four phases: coagulation, inflammation, proliferation, and remodeling. The potential of natural products in the treatment of wounds has been reported in numerous studies, emphasizing those with antioxidant, anti-inflammatory, and antimicrobial properties, e.g., alkaloids, saponins, terpenes, essential oils, and polyphenols from different plant sources, since these compounds can interact in the various stages of the wound healing process. This review addresses the most current in vitro and in vivo studies on the wound healing potential of natural products, as well as the main mechanisms involved in this activity. We observed sufficient evidence of the activity of these compounds in the treatment of wounds; however, we also found that there is no consensus on the effective concentrations in which the natural products exert this activity. For this reason, it is important to work on establishing optimal treatment doses, as well as an appropriate route of administration. In addition, more research should be carried out to discover the possible side effects and the behavior of natural products in clinical trials.


Asunto(s)
Productos Biológicos , Productos Biológicos/farmacología , Productos Biológicos/uso terapéutico , Cicatrización de Heridas , Piel , Extractos Vegetales/química , Antiinflamatorios/farmacología , Antiinflamatorios/uso terapéutico
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