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1.
Am J Bot ; 111(7): e16374, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39001581

RESUMEN

PREMISE: Bracken (Pteridium, Dennstaedtiaceae) is a cosmopolitan genus of aggressive disturbance colonizers that are toxic to agricultural livestock. The taxonomy of Pteridium has been treated in multiple schemes, ranging from one to six species worldwide, with numerous subspecies and varieties. Recent work has focused on the worldwide distribution and systematics of the bracken fern, but South America has been poorly represented. We present the first continent-wide sampling and analysis of Pteridium esculentum, a Southern Hemisphere diploid species. METHODS: Within South America, P. esculentum has several morphotypes, distinguished into subspecies by variation in indument and lamina architecture. We used double digest restriction site-associated DNA sequencing (ddRADSeq) to assess the phylogenetic relationships of P. esculentum subspecies. RESULTS: We found a striking genetic homogeneity in the species, being able to support only two morphotypes from molecular data: P. e. arachnoideum and P. e. campestre. We had high confidence for shallow and deep phylogenetic relationships, but less support for relationships among crown groups. CONCLUSIONS: We describe an east-west geographic pattern that would explain the relationships between populations; and, in contrast to previous studies, we detected differences with P. esculentum from Australia. These results will lay the foundations for studying variations in this species' behavior as a weed, as well as its impact on the production of agricultural livestock in South America.


Asunto(s)
Filogenia , Pteridium , América del Sur , Pteridium/genética , Variación Genética , Análisis de Secuencia de ADN
2.
Inorg Chem ; 62(31): 12392-12402, 2023 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-37478498

RESUMEN

The influence of manganese modification on the spectroscopic features of manganese-doped CeO2 systems synthesized by the microwave-assisted hydrothermal route and their correlation with the presence of O defective structures were verified, focusing on their interaction with poisonous atmospheres. Raman and electron paramagnetic resonance studies confirmed the presence of defective clusters formed by dipoles and/or quadrupoles. The number of paramagnetic species was found to be inversely proportional to the doping concentration, resulting in an increase in the Mn2+ signal, likely due to the reduction of Mn3+ species after the interaction with CO. X-ray photoelectron spectroscopy data showed the pure system with 33% of its cerium species in the Ce3+ configuration, with an abrupt decrease to 19%, after the first modification with Mn, suggesting that 14% of the Ce3+ species are donating one electron to the Mn2+ ions, thus becoming nonparamagnetic Ce4+ species. On the contrary, 58% of the manganese species remain in the Mn2+ configuration with five unpaired electrons, corroborating the paramagnetic feature of the samples seen in the electron paramagnetic resonance study.

3.
J Environ Manage ; 330: 117158, 2023 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-36603253

RESUMEN

Developing technological solutions that use yerba mate waste as precursors is key to reducing the environmental impact caused by the lack of treatment and its accumulation in landfills. Due to their physicochemical properties, these residues can be used to develop activated carbons. Activated carbon is a versatile material with a high surface area that can be used for energy storage. In this work, yerba mate residues were valued by producing chemically activated carbon to be used as electrode material in supercapacitors. Activated carbons were developed through chemical activation in two steps with KOH. Variables such as impregnation ratio and activation temperature are studied. The developed carbons were characterized by physicochemical and electrochemical techniques. They were found to have high surface areas, up to 1800 m2 g-1, with a hierarchical porous distribution. A maximum specific capacitance of 644 F g-1 at 0.1 A g-1, and power values of ca 32,000 W kg-1, at 33 A g-1 were found. All the synthesized carbons have excellent electrochemical properties and are suitable for use as active material in supercapacitors.


Asunto(s)
Carbón Orgánico , Ilex paraguariensis , Capacidad Eléctrica , Electrodos , Porosidad
4.
An Acad Bras Cienc ; 94(3): e20201870, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36074404

RESUMEN

The Yabotí Biosphere Reserve (Prov. Misiones, Argentina) with 221,155 ha, represents one of the southernmost relicts of the Paranaense forest. Currently, a project is being developed in the area to inventory and describe the ferns and lycophytes. As a result of these studies, we identify a new species of Amauropelta, A. yabotiensis. Within this genus, it belongs to the group of species with uncinate hairs and presents a unique combination of diagnostic features, including the type of pubescence on the rhizome scales, the shape of the fronds and segments and type of venation. Here, we described and illustrated the species and we analyzed its taxonomic affinities and geographic distribution. Additionally, we provided a distribution map and a key to distinguish it from other Amauropelta species from Misiones province. With this new finding, we highlighted the importance of the Yabotí Reserve as a reservoir of biodiversity in the region.


Asunto(s)
Biodiversidad , Helechos , Argentina , Bosques
5.
Matern Child Health J ; 23(Suppl 1): 4-17, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29868936

RESUMEN

Introduction Even though micronutrient deficiency is still a major public health problem, it is still unclear which interventions are most effective in improving micronutrient status. This review therefore aims to summarize the evidence published in systematic reviews on intervention strategies that aim at improving micronutrient status in children under the age of five. Methods We searched the literature and included systematic reviews that reported on micronutrient status as a primary outcome for children of 0-5 years old, had a focus on low or middle income countries. Subsequently, papers were reviewed and selected by two authors. Results We included 4235 reviews in this systematic review. We found that (single or multiple) micronutrient deficiencies in pre-school children improved after providing (single or multiple) micronutrients. However home fortification did not always lead to significant increase in serum vitamin A, serum ferritin, hemoglobin or zinc. Commercial fortification did improve iron status. Cord clamping reduced the risk of anemia in infants up to 6 months and, in helminth endemic areas, anthelminthic treatment increased serum ferritin levels, hemoglobin and improved height for age z-scores. Anti-malaria treatment improved ferritin levels. Discussion Based on our results the clearest recommendations are: delayed cord clamping is an effective intervention for reducing anemia in early life. In helminth endemic areas iron status can be improved by anthelminthic treatment. Anti-malaria treatment can improve ferritin. In deficient populations, single iron, vitamin A and multimicronutrient supplementation can improve iron, vitamin A and multimicronutrient status respectively. While the impact of home-fortification on multimicronutrient status remains questionable, commercial iron fortification may improve iron status.


Asunto(s)
Anemia Ferropénica/dietoterapia , Antihelmínticos/administración & dosificación , Antimaláricos/administración & dosificación , Suplementos Dietéticos , Alimentos Fortificados , Helmintiasis/prevención & control , Malaria/prevención & control , Micronutrientes/administración & dosificación , Micronutrientes/deficiencia , Anemia/epidemiología , Preescolar , Femenino , Helmintiasis/parasitología , Humanos , Recién Nacido , Malaria/parasitología , Masculino
6.
Matern Child Health J ; 23(Suppl 1): 29-45, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30506126

RESUMEN

Objectives Since the 1990s, programs for the control of micronutrient deficiencies became a public health priority for many governments, including the countries partnering the project "Sustainable Micronutrient Interventions to Control Deficiencies and Improve Nutritional Status and General Health in Asia" (SMILING): Cambodia, Indonesia, Laos-PDR, Thailand and Vietnam. The aim of this study was to map which micronutrient deficiencies have been addressed and which interventions were in place in the SMILING countries. Methods The mapping covered the period up to 2012. Updated information from relevant surveys after 2012 is included in this paper after the completion of the SMILING project. The mapping of micronutrient status was limited to either national or at least large-scale surveys. Information on nutrition interventions obtained through a systematic mapping of national programs combined with a snowball collection from various sources. Results Among the five SMILING countries, Thailand differed historically by an early implementation of a nationwide community-based nutrition program, contributing to reductions in undernutrition and micronutrient deficiencies. For Cambodia, Indonesia, Laos PDR, and Vietnam, some national programs addressing micronutrients have been implemented following adjusted international recommendations. National surveys on micronutrient status were scattered and inconsistent across the countries in design and frequency. Conclusion for practice In conclusion, some micronutrient deficiencies were addressed in national interventions but the evidence of effects was generally lacking because of limited nationally representative data collected. Improvement of intervention programs to efficiently reduce or eliminate micronutrient deficiencies requires more systematic monitoring and evaluation of effects of interventions in order to identify best practices.


Asunto(s)
Anemia/etiología , Hierro , Desnutrición/prevención & control , Micronutrientes/deficiencia , Estado Nutricional , Deficiencia de Vitamina A , Deficiencia de Vitamina B 12 , Adolescente , Adulto , Anemia/metabolismo , Anemia Ferropénica , Asia Sudoriental , Niño , Femenino , Deficiencia de Ácido Fólico/complicaciones , Humanos , Hierro/metabolismo , Deficiencias de Hierro , Masculino , Persona de Mediana Edad , Evaluación de Programas y Proyectos de Salud , Deficiencia de Vitamina A/complicaciones , Deficiencia de Vitamina B 12/complicaciones , Adulto Joven
7.
J Cell Sci ; 129(21): 3989-4000, 2016 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-27624612

RESUMEN

To ensure normal immune function, mast cells employ different pathways to release mediators. Here, we report a thus far unknown capacity of mast cells to recycle and reuse secretory granules after an antigen-evoked degranulation process under physiological conditions; this phenomenon involves the existence of a recycling secretory granule pool that is available for release in a short time scale. Rapid endocytic modes contributed to the recycling of ∼60% of the total secretory granule population, which involved kiss-and-run and cavicapture mechanisms, causing retention of the intragranular matrix. We found the presence of normal-size granules and giant actomyosin- and dynamin-dependent granules, which were characterized by large quantal content. These large structures allowed the recovered mast cells to release a large amount of 5-HT, compensating for the decrease in the number of exocytosed secretory granules. This work uncovers a new physiological role of the exo-endocytosis cycle in the immunological plasticity of mast cells and reveals a new property of their biological secretion.


Asunto(s)
Degranulación de la Célula , Inmunoglobulina E/metabolismo , Mastocitos/fisiología , Fusión de Membrana , Vesículas Secretoras/metabolismo , Actinas/metabolismo , Animales , Antígenos/metabolismo , Calcimicina/farmacología , Degranulación de la Célula/efectos de los fármacos , Dinaminas/metabolismo , Técnicas Electroquímicas , Endocitosis/efectos de los fármacos , Exocitosis/efectos de los fármacos , Mastocitos/efectos de los fármacos , Fusión de Membrana/efectos de los fármacos , Ratones Endogámicos C57BL , Modelos Biológicos , Miosina Tipo II/metabolismo , Vesículas Secretoras/efectos de los fármacos , Serotonina/metabolismo
8.
J Intern Med ; 284(1): 61-77, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29532531

RESUMEN

BACKGROUND: Rheumatoid arthritis (RA) patients are at increased risk of insulin resistance (IR); however, the specific mechanisms mediating this association are currently unknown. OBJECTIVE: To investigate whether the inflammatory activity associated with RA accounts for the observed defective glucose metabolism and lipid metabolism in these patients. METHODS: We followed two main strategies: (i) extensive metabolic profiling of a RA cohort of 100 patients and 50 healthy control subjects and (ii) mechanistic studies carried out in both a collagen-induced arthritis mouse model and 3T3-L1 adipocytes treated with conditioned serum from RA patients. RESULTS: Following the exclusion of obese and diabetic subjects, data from RA patients demonstrated a strong link between the degree of systemic inflammation and the development of IR. These results were strengthened by the observation that induction of arthritis in mice resulted in a global inflammatory state characterized by defective carbohydrate and lipid metabolism in different tissues. Adipose tissue was most susceptible to the RA-induced metabolic alterations. These metabolic effects were confirmed in adipocytes treated with serum from RA patients. CONCLUSIONS: Our results show that the metabolic disturbances associated with RA depend on the degree of inflammation and identify inflammation of adipose tissue as the initial target leading to IR and the associated molecular disorders of carbohydrate and lipid homeostasis. Thus, we anticipate that therapeutic strategies based on tighter control of inflammation and flares could provide promising approaches to normalize and/or prevent metabolic alterations associated with RA.


Asunto(s)
Artritis Reumatoide/sangre , Glucemia/metabolismo , Inflamación/sangre , Lípidos/sangre , Células 3T3-L1 , Adipocitos/metabolismo , Tejido Adiposo/metabolismo , Adulto , Anciano , Animales , Artritis Experimental/sangre , Estudios de Casos y Controles , Enfermedad Crónica , Estudios de Cohortes , Femenino , Humanos , Resistencia a la Insulina/fisiología , Masculino , Ratones , Persona de Mediana Edad
9.
Parasite Immunol ; 40(4): e12518, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29364525

RESUMEN

The aim of the present study was to evaluate associations between intestinal parasitic infection with intestinal and systemic inflammatory markers in school-aged children with high rates of obesity. Plasma concentrations of C-Reactive Protein (CRP), leptin, TNF-α, IL-6 and IL-10 were measured as systemic inflammation markers and count of stool leukocytes as marker of intestinal inflammation in 291 children (6-10 years). Intestinal parasitic infection was measured by stool examination. Logistic regression analyses were performed to determine the odds of having high inflammatory markers for each parasite or group of parasites as compared to parasite-free children while adjusting for sex, age, mother's educational level and percentage of body fat. The prevalence of soil-transmitted helminths and intestinal protozoa infections was 12% and 36%, respectively. Parasitic infection was not associated with CRP, IL-6, IL-10 or TNF-α. Children infected with Ascaris lumbricoides (aOR: 5.91, 95% CI: 1.97-17.70) and Entamoeba coli (aOR: 8.46, 95% CI: 2.85-25.14) were more likely to have higher stool leucocytes than parasite-free children. Children with multiple infections (aOR: 10.60, 95% CI: 2.85-25.14) were more likely to have higher leptin concentrations than parasite-free children. Intestinal parasitic infection was not associated with systemic inflammation, but was associated with intestinal inflammation. Having multiple infections were associated with higher leptin concentrations.


Asunto(s)
Helmintiasis/sangre , Helmintiasis/inmunología , Parasitosis Intestinales/sangre , Parasitosis Intestinales/inmunología , Intestinos/parasitología , Leptina/sangre , Animales , Ascaris lumbricoides/inmunología , Proteína C-Reactiva/metabolismo , Niño , Estudios Transversales , Entamoeba histolytica/inmunología , Heces/parasitología , Femenino , Helmintiasis/parasitología , Humanos , Inflamación , Interleucina-10/sangre , Interleucina-6/sangre , Parasitosis Intestinales/parasitología , Masculino , Obesidad/complicaciones , Prevalencia , Encuestas y Cuestionarios , Factor de Necrosis Tumoral alfa/sangre
10.
J Immunol ; 195(5): 2046-56, 2015 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-26202981

RESUMEN

The key role of mast cells (MC), either in development of inflammatory pathologies or in response to environmental stress, has been widely reported in recent years. Previous studies have described the effects of corticotropin-releasing hormone (CRH), which is released from inflamed tissues by cellular stress signals, on MC degranulation, a process possibly driven by selective secretion of mediators (piecemeal degranulation). In this study, we introduce a novel granular exo-endocytic pathway induced by CRH on peritoneal MC. We found that CRH triggers substantial exocytosis, which is even stronger than that induced by Ag stimulation and is characterized by large quantal size release events. Membrane fluorescence increases during stimulation in the presence of FM1-43 dye, corroborating the strength of this exocytosis, given that discrete upward fluorescence steps are often observed and suggesting that secretory granules are preferentially released by compound exocytosis. Additionally, the presence of a depot of large tubular organelles in the cytoplasm suggests that the exocytotic process is tightly coupled to a fast compound endocytosis. This CRH-stimulated mechanism is mediated through activation of adenylate cyclase and an increase of cAMP and intracellular Ca(2+), as evidenced by the fact that the effect of CRH is mimicked by forskolin and 8-bromo-cAMP. Thus, these outcomes constitute new evidence for the critical role of MC in pathophysiological conditions within a cellular stress environment and an alternative membrane trafficking route mediated by CRH.


Asunto(s)
Hormona Liberadora de Corticotropina/farmacología , Endocitosis/efectos de los fármacos , Exocitosis/efectos de los fármacos , Mastocitos/metabolismo , 8-Bromo Monofosfato de Adenosina Cíclica/farmacología , Adenilil Ciclasas/metabolismo , Animales , Calcio/metabolismo , Degranulación de la Célula/efectos de los fármacos , Células Cultivadas , Colforsina/farmacología , AMP Cíclico/metabolismo , Activación Enzimática/efectos de los fármacos , Espacio Intracelular/efectos de los fármacos , Espacio Intracelular/metabolismo , Mastocitos/fisiología , Ratones Endogámicos C57BL , Microscopía Confocal , Compuestos de Piridinio/metabolismo , Compuestos de Amonio Cuaternario/metabolismo , Ratas Wistar , Vesículas Secretoras/metabolismo
11.
Biochem Biophys Res Commun ; 469(3): 559-64, 2016 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-26692491

RESUMEN

5-hydroxytriptamine (5-HT, serotonin) storage and release in mast cell (MC) secretory granules (SG) are dependent on serglycin proteoglycans (PG). This notion is based on the studies of MC of the connective tissue subtype that predominantly contain PG of the heparin type, whereas intestinal mucosal MC, which contain predominantly chondroitin sulfate, have been poorly explored. In the present study, we addressed the possibility that PG contents may differently affect the storage and release of preformed mediators in these two MC subclasses and explain in part their different functional properties. Rat peritoneal (PMC) and intestinal mast cells (IMC) were isolated and purified using a percoll gradient, and the efflux of 5-HT from each SG was measured by amperometric detection. IMC exhibited a ∼34% reduction in the release of 5-HT compared with PMC because of a lower number of exocytotic events, rather than a lower secretion per single exocytotic event. Amperometric spikes from IMC exhibited a slower decay phase and increased half-width but a similar ascending phase and foot parameters, indicating that the fusion pore kinetics are comparable in both MC subclasses. We conclude that both PG subtypes are equally efficient systems, directly involved in serotonin accumulation, and play a crucial role in regulating the kinetics of exocytosis from SG, providing specific secretory properties for the two cellular subtypes.


Asunto(s)
Mucosa Intestinal/metabolismo , Intestinos/citología , Mastocitos/metabolismo , Peritoneo/citología , Peritoneo/metabolismo , Serotonina/metabolismo , Animales , Células Cultivadas , Exocitosis/fisiología , Cinética , Mastocitos/citología , Tasa de Depuración Metabólica , Especificidad de Órganos/fisiología , Ratas , Ratas Wistar
12.
Allergy ; 71(10): 1393-404, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27286276

RESUMEN

IgE-mediated reactions to food allergens are the most common cause of anaphylaxis in childhood. Although allergies to cow's milk, egg, or soy proteins, in contrast to peanut and tree nut allergens, resolve within the first 6 years of life in up to 60% due to natural tolerance development, this process is not well understood. At present, there is no cure or treatment for food allergy that would result in an induction of tolerance to the symptom-eliciting food. Avoidance, providing an emergency plan and education, is the standard of treatment. Oral immunotherapeutic approaches have been proven reasonable efficacy; however, they are associated with high rates of side-effects and low numbers of patients achieving tolerance. Nevertheless, mechanisms that take place during oral immunotherapy may help to understand tolerance development. On the basis of these therapeutic interventions, events like loss of basophil activation and induction of regulatory lymphocyte subsets and of blocking antibodies have been described. Their functional importance at a clinical level, however, remains to be investigated in detail. Consequently, there is eminent need to understand the process of tolerance development to food allergens and define biomarkers to develop and monitor new treatment strategies for food allergy.


Asunto(s)
Alérgenos/inmunología , Hipersensibilidad a los Alimentos/inmunología , Alimentos/efectos adversos , Tolerancia Inmunológica , Animales , Biomarcadores , Desensibilización Inmunológica , Modelos Animales de Enfermedad , Femenino , Hipersensibilidad a los Alimentos/diagnóstico , Hipersensibilidad a los Alimentos/terapia , Humanos , Inmunidad Mucosa , Inmunización , Inmunoglobulina E/inmunología , Exposición Materna , Ratones , Embarazo , Efectos Tardíos de la Exposición Prenatal/inmunología
13.
Br J Cancer ; 112(12): 1866-73, 2015 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-25996206

RESUMEN

BACKGROUND: Chronic tissue damage induced by Helicobacter pylori (HP)-driven inflammation is considered the main risk of gastric carcinoma (GC). Epstein­Barr virus (EBV) infection has also been associated with GC. In this study, we aim to address the role of EBV in inflammatory GC precursor lesions and its added risk to HP infection. METHODS: Antibodies against EBV, HP and the bacterial virulence factor CagA were measured in sera from 525 Mexican and Paraguayan patients with gastric disease. Gastric samples were characterised according to the updated Sydney classification and associations were estimated between antibody responses and severity of both tissue damage and inflammation. RESULTS: We found significant associations (odd ratios and trends) between EBV and HP copositivity and premalignant lesions and intestinal-type GC. The EBV and HP coinfection was also significantly associated with increased infiltration of immune cells. No association was found between EBV and the less inflammation-driven diffuse-type GC. CONCLUSIONS: Our study suggests that EBV co-participates with HP to induce severe inflammation, increasing the risk of progression to intestinal-type GC.


Asunto(s)
Infecciones por Virus de Epstein-Barr/patología , Infecciones por Helicobacter/patología , Helicobacter pylori/aislamiento & purificación , Herpesvirus Humano 4/aislamiento & purificación , Gastropatías/sangre , Gastropatías/microbiología , Adulto , Estudios de Casos y Controles , Infecciones por Virus de Epstein-Barr/sangre , Infecciones por Virus de Epstein-Barr/microbiología , Infecciones por Virus de Epstein-Barr/virología , Femenino , Gastritis/sangre , Gastritis/microbiología , Gastritis/patología , Infecciones por Helicobacter/sangre , Infecciones por Helicobacter/microbiología , Infecciones por Helicobacter/virología , Humanos , América Latina , Masculino , México , Persona de Mediana Edad , Paraguay , Gastropatías/patología , Gastropatías/virología , Neoplasias Gástricas/sangre , Neoplasias Gástricas/microbiología , Neoplasias Gástricas/patología
14.
Ann Bot ; 114(7): 1471-81, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24989784

RESUMEN

BACKGROUND AND AIMS: The TERMINAL FLOWER 1 (TFL1) gene is pivotal in the control of inflorescence architecture in arabidopsis. Thus, tfl1 mutants flower early and have a very short inflorescence phase, while TFL1-overexpressing plants have extended vegetative and inflorescence phases, producing many coflorescences. TFL1 is expressed in the shoot meristems, never in the flowers. In the inflorescence apex, TFL1 keeps the floral genes LEAFY (LFY) and APETALA1 (AP1) restricted to the flower, while LFY and AP1 restrict TFL1 to the inflorescence meristem. In spite of the central role of TFL1 in inflorescence architecture, regulation of its expression is poorly understood. This study aims to expand the understanding of inflorescence development by identifying and studying novel TFL1 regulators. METHODS: Mutagenesis of an Arabidopsis thaliana line carrying a TFL1::GUS (ß-glucuronidase) reporter construct was used to isolate a mutant with altered TFL1 expression. The mutated gene was identified by positional cloning. Expression of TFL1 and TFL1::GUS was analysed by real-time PCR and histochemical GUS detection. Double-mutant analysis was used to assess the contribution of TFL1 to the inflorescence mutant phenotype. KEY RESULTS: A mutant with both an increased number of coflorescences and high and ectopic TFL1 expression was isolated. Cloning of the mutated gene showed that both phenotypes were caused by a mutation in the ARGONAUTE1 (AGO1) gene, which encodes a key component of the RNA silencing machinery. Analysis of another ago1 allele indicated that the proliferation of coflorescences and ectopic TFL1 expression phenotypes are not allele specific. The increased number of coflorescences is suppressed in ago1 tfl1 double mutants. CONCLUSIONS: The results identify AGO1 as a repressor of TFL1 expression. Moreover, they reveal a novel role for AGO1 in inflorescence development, controlling the production of coflorescences. AGO1 seems to play this role through regulating TFL1 expression.


Asunto(s)
Proteínas de Arabidopsis/genética , Arabidopsis/genética , Proteínas Argonautas/genética , Regulación de la Expresión Génica de las Plantas , Inflorescencia/genética , Arabidopsis/anatomía & histología , Arabidopsis/crecimiento & desarrollo , Proteínas de Arabidopsis/metabolismo , Proteínas Argonautas/metabolismo , Regulación del Desarrollo de la Expresión Génica , Genes Reporteros , Glucuronidasa , Inflorescencia/anatomía & histología , Inflorescencia/crecimiento & desarrollo , Proteínas de Dominio MADS/genética , Proteínas de Dominio MADS/metabolismo , Meristema/anatomía & histología , Meristema/genética , Meristema/crecimiento & desarrollo , Mutación , Fenotipo
15.
Nanotechnology ; 25(25): 255202, 2014 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-24897432

RESUMEN

We report on the growth and microstructure analysis of high Cd content ZnCdO/ZnO multiple quantum wells (MQW) within a nanowire. Heterostructures consisting of ten wells with widths from 0.7 to 10 nm are demonstrated, and show photoluminescence emissions ranging from 3.03 to 1.97 eV. The wells with thicknesses ≦̸2 nm have high radiative efficiencies compared to the thickest ones, consistent with the presence of quantum confinement. However, a nanometric analysis of the Cd profile along the heterostructures shows the presence of Cd diffusion from the ZnCdO well to the ZnO barrier. This phenomenon modifies the band structure and the optical properties of the heterostructure, and is considered in order to correctly identify quantum effects in the ZnCdO/ZnO MQWs.

16.
Neuroimage Clin ; 41: 103570, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38309185

RESUMEN

Impaired motion perception in schizophrenia has been associated with deficits in social-cognitive processes and with reduced activation of visual sensory regions, including the middle temporal area (MT+) and posterior superior temporal sulcus (pSTS). These findings are consistent with the recent proposal of the existence of a specific 'third visual pathway' specialized for social perception in which motion is a fundamental component. The third visual pathway transmits visual information from early sensory visual processing areas to the STS, with MT+ acting as a critical intermediary. We used functional magnetic resonance imaging to investigate functioning of this pathway during processing of naturalistic videos with explicit (real) motion and static images with implied motion cues. These measures were related to face emotion recognition and motion-perception, as measured behaviorally. Participants were 28 individuals with schizophrenia (Sz) and 20 neurotypical controls. Compared to controls, individuals with Sz showed reduced activation of third visual pathway regions (MT+, pSTS) in response to both real- and implied-motion stimuli. Dysfunction of early visual cortex and pulvinar were also associated with aberrant real-motion processing. Implied-motion stimuli additionally engaged a wide network of brain areas including parietal, motor and frontal nodes of the human mirror neuron system. The findings support concepts of MT+ as a mediator between visual sensory areas and higher-order brain and argue for greater focus on MT+ contributions to social-cognitive processing, in addition to its well-documented role in visual motion processing.


Asunto(s)
Percepción de Movimiento , Esquizofrenia , Humanos , Esquizofrenia/diagnóstico por imagen , Vías Visuales/diagnóstico por imagen , Lóbulo Temporal , Encéfalo/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Mapeo Encefálico , Percepción de Movimiento/fisiología , Estimulación Luminosa/métodos
17.
Microbiol Spectr ; 12(7): e0394723, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38864670

RESUMEN

Clostridioides difficile (C. difficile) is widely distributed in the intestinal tract of humans, animals, and in the environment. It is the most common cause of diarrhea associated with the use of antimicrobials in humans and among the most common healthcare-associated infections worldwide. Its pathogenesis is mainly due to the production of toxin A (TcdA), toxin B (TcdB), and a binary toxin (CDT), whose genetic variants may be associated with disease severity. We studied genetic diversity in 39 C. difficile isolates from adults and children attended at two Mexican hospitals, using different gene and genome typing methods and investigated their association with in vitro expression of toxins. Whole-genome sequencing in 39 toxigenic C. difficile isolates were used for multilocus sequence typing, tcdA, and tcdB typing sequence type, and phylogenetic analysis. Strains were grown in broth media, and expression of toxin genes was measured by real-time PCR and cytotoxicity in cell-culture assays. Clustering of strains by genome-wide phylogeny matched clade classification, forming different subclusters within each clade. The toxin profile tcdA+/tcdB+/cdt+ and clade 2/ST1 were the most prevalent among isolates from children and adults. Isolates presented two TcdA and three TcdB subtypes, of which TcdA2 and TcdB2 were more prevalent. Prevalent clades and toxin subtypes in strains from children differed from those in adult strains. Toxin gene expression or cytotoxicity was not associated with genotyping or toxin subtypes. In conclusion, genomic and phenotypic analysis shows high diversity among C. difficile isolates from patients with healthcare-associated diarrhea. IMPORTANCE: Clostridioides difficile is a toxin-producing bacterial pathogen recognized as the most common cause of diarrhea acquired primarily in healthcare settings. This bacterial species is diverse; its global population has been divided into five different clades using multilocus sequence typing, and strains may express different toxin subtypes that may be related to the clades and, importantly, to the severity and progression of disease. Genotyping of children strains differed from adults suggesting toxins might present a reduced toxicity. We studied extensively cytotoxicity, expression of toxins, whole genome phylogeny, and toxin typing in clinical C. difficile isolates. Most isolates presented a tcdA+/ tcdB+/cdt+ pattern, with high diversity in cytotoxicity and clade 2/ST1 was the most prevalent. However, they all had the same TcdA2/TcdB2 toxin subtype. Advances in genomics and bioinformatics tools offer the opportunity to understand the virulence of C. difficile better and find markers for better clinical use.


Asunto(s)
Toxinas Bacterianas , Clostridioides difficile , Infecciones por Clostridium , Infección Hospitalaria , Diarrea , Variación Genética , Tipificación de Secuencias Multilocus , Filogenia , Humanos , Clostridioides difficile/genética , Clostridioides difficile/clasificación , Clostridioides difficile/aislamiento & purificación , Diarrea/microbiología , Diarrea/epidemiología , México/epidemiología , Niño , Toxinas Bacterianas/genética , Adulto , Infecciones por Clostridium/microbiología , Infecciones por Clostridium/epidemiología , Infección Hospitalaria/microbiología , Infección Hospitalaria/epidemiología , Proteínas Bacterianas/genética , Enterotoxinas/genética , Masculino , Preescolar , Femenino , Prevalencia , Adolescente , Secuenciación Completa del Genoma , Fenotipo , Genoma Bacteriano/genética , Lactante , Persona de Mediana Edad , Genómica
18.
Mar Pollut Bull ; 199: 115981, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38171164

RESUMEN

Remote sensing data and numerical simulation are important tools to rebuild any oil spill accident letting to identify its source and trajectory. Through these tools was identified an oil spill that affected Oaxacan coast in October 2022. The SAR images were processed with a standard method included in SNAP software, and the numerical simulation was made using Lagrangian transport model included in GNOME software. With the combining of these tools was possible to discriminate the look-alikes from true oil slicks; which are the main issue when satellite images are used. Obtained results showed that 4.3m3 of crude oil were released into the ocean from a punctual point of oil pollution. This oil spill was classified such as a small oil spill. The marine currents and weathering processes were the main drivers that controlled the crude oil displacement and its dispersion. It was estimated in GNOME that 1.6 m3 of crude oil was floating on the sea (37.2 %), 2.4 m3 was evaporated into the atmosphere (55.8 %) and 0.3 m3 reached the coast of Oaxaca (7 %). This event affected 82 km of coastline, but the most important touristic areas as well as turtle nesting zones were not affected by this small crude oil spill. Results indicated that the marine-gas-pump number 3 in Salina Cruz, Oaxaca, is a punctual point of oil pollution in the Southern Mexican Pacific Ocean. Further work is needed to assess the economic and ecological damage to Oaxacan coast caused by this small oil spill.


Asunto(s)
Contaminación por Petróleo , Petróleo , Contaminación por Petróleo/análisis , Monitoreo del Ambiente/métodos , Tecnología de Sensores Remotos , Petróleo/análisis , Tiempo (Meteorología)
19.
Neurologia (Engl Ed) ; 39(1): 63-83, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38065433

RESUMEN

INTRODUCTION: Gamification consists of the use of games in non-playful contexts. It is widely employed in the motor rehabilitation of neurological diseases, but mainly in adult patients. The objective of this review was to describe the use of gamification in the rehabilitation of children and adolescents with neuromotor impairment. METHODS: We performed a systematic review of clinical trials published to date on the MEDLINE (PubMed), Scielo, SCOPUS, Dialnet, CINAHL, and PEDro databases, following the PRISMA protocol. The methodological quality of the studies identified was assessed using the PEDro scale. RESULTS: From a total of 469 studies, 11 clinical trials met the inclusion criteria. We analysed the gamification systems used as part of the rehabilitation treatment of different neuromotor conditions in children and adolescents. Cerebral palsy was the most frequently studied condition (6 studies), followed by developmental coordination disorder (3), neurological gait disorders (1), and neurological impairment of balance and coordination (1). CONCLUSION: The use of gamification in rehabilitation is helpful in the conventional treatment of neuromotor disorders in children and adolescents, with increased motivation and therapeutic adherence being the benefits with the greatest consensus among authors. While strength, balance, functional status, and coordination also appear to improve, future research should aim to determine an optimal dosage.


Asunto(s)
Parálisis Cerebral , Trastornos del Movimiento , Rehabilitación Neurológica , Niño , Humanos , Adolescente , Gamificación , Marcha
20.
Sci Total Environ ; 940: 173440, 2024 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-38802018

RESUMEN

Despite their ability to mitigate climate change by efficiently absorbing atmospheric carbon dioxide (CO2) and acting as natural long-term carbon sinks, mangrove ecosystems have faced several anthropogenic threats over the past century, resulting in a decline in the global mangrove cover. By using standardized methods and the most recent Bayesian tracer mixing models MixSIAR, this study aimed to quantify source contributions, burial rates, and stocks of organic carbon (Corg) and explore their temporal changes (∼100 years) in seven lead-210 dated sediment cores collected from three contrasting Mexican mangrove areas. The spatial variation in Corg burial rates and stocks in these blue carbon ecosystems primarily depended on the influence of local rivers, which controlled Corg sources and fluxes within the mangrove areas. The Corg burial rates in the cores ranged from 66 ± 16 to 400 ± 40 g m-2 yr-1. The Corg stocks ranged from 84.9 ± 0.7 to 255 ± 2 Mg ha-1 at 50 cm depth and from 137 ± 2 to 241 ± 4 Mg ha-1 at 1 m depth. The highest Corg burial rates and stocks were observed in cores from the carbonate platform of Yucatan and in cores with reduced river influence and high mangrove detritus inputs, in contrast to patterns identified from global databases. Over the past century, the rising trends in Corg burial rates and stocks in the study sites were primarily driven by enhanced inputs of fluvial-derived Corg and, in some cores, mangrove-derived Corg. Despite their decreasing extension, mangrove areas remained highly effective producers and sinks of Corg. Ongoing efforts to enhance the global database should continue, including mangrove area characteristics and reliable timescales to facilitate cross-comparison among studies.

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