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1.
Biomacromolecules ; 25(7): 4192-4202, 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38917475

RESUMEN

The permeability and responsiveness of polymer membranes are absolutely relevant in the design of polymersomes for cargo delivery. Accordingly, we herein correlate the structural features, permeability, and responsiveness of doxorubicin-loaded (DOX-loaded) nonresponsive and stimuli-responsive polymersomes with their in vitro and in vivo antitumor performance. Polymer vesicles were produced using amphiphilic block copolymers containing a hydrophilic poly[N-(2-hydroxypropyl)methacrylamide] (PHPMA) segment linked to poly[N-(4-isopropylphenylacetamide)ethyl methacrylate] (PPPhA, nonresponsive block), poly[4-(4,4,5,5-tetra-methyl-1,3,2-dioxaborolan-2-yl)benzyl methacrylate] [PbAPE, reactive oxygen species (ROS)-responsive block], or poly[2-(diisopropylamino)ethyl methacrylate] (PDPA, pH-responsive block). The PDPA-based polymersomes demonstrated outstanding biological performance with antitumor activity notably enhanced compared to their counterparts. We attribute this behavior to a fast-triggered DOX release in acidic tumor environments as induced by pH-responsive polymersome disassembly at pH < 6.8. Possibly, an insufficient ROS concentration in the selected tumor model attenuates the rate of ROS-responsive vesicle degradation, whereas the nonresponsive nature of the PPPhA block remarkably impacts the performance of such potential nanomedicines.


Asunto(s)
Doxorrubicina , Doxorrubicina/farmacología , Doxorrubicina/química , Humanos , Animales , Ratones , Permeabilidad de la Membrana Celular/efectos de los fármacos , Polímeros/química , Polímeros/farmacología , Antibióticos Antineoplásicos/farmacología , Antibióticos Antineoplásicos/química , Portadores de Fármacos/química , Especies Reactivas de Oxígeno/metabolismo , Antineoplásicos/farmacología , Antineoplásicos/química , Línea Celular Tumoral , Acrilamidas/química , Acrilamidas/farmacología , Concentración de Iones de Hidrógeno
2.
BMC Pulm Med ; 23(1): 406, 2023 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-37884922

RESUMEN

BACKGROUND: Lung function analysis in Parkinson's disease (PD) is often difficult due to the demand for adequate forced expiratory maneuvers. Respiratory oscillometry exams require onlyquiet tidal breathing and provide a detailed analysis of respiratory mechanics. We hypothesized that oscillometry would simplify the diagnosis of respiratory abnormalitiesin PD and improve our knowledge about the pathophysiological changes in these patients. MATERIALS AND METHODS: This observational study includes 20 controls and 47 individuals with PD divided into three groups (Hoehn and Yahr Scale 1-1.5; H&Y scale 2-3 and PD smokers).The diagnostic accuracy was evaluated by investigating the area under the receiver operating characteristic curve (AUC). RESULTS: Initial stages are related to increased peripheral resistance (Rp; p = 0.001). In more advanced stages, a restrictive pattern is added, reflected by reductions in dynamic compliance (p < 0.05) and increase in resonance frequency (Fr; p < 0.001). Smoking PD patients presented increased Rp (p < 0.001) and Fr (p < 0.01). PD does not introduce changes in the central airways. Oscillometric changes were correlated with respiratory muscle weakness (R = 0.37, p = 0.02). Rp showed adequate accuracy in the detection of early respiratory abnormalities (AUC = 0.858), while in more advanced stages, Fr showed high diagnostic accuracy (AUC = 0.948). The best parameter to identify changes in smoking patients was Rp (AUC = 0.896). CONCLUSION: The initial stages of PD are related to a reduction in ventilation homogeneity associated with changes in peripheral airways. More advanced stages also include a restrictive ventilatory pattern. These changes were correlated with respiratory muscle weakness and were observed in mild and moderate stages of PD in smokers and non-smokers. Oscillometry may adequately identify respiratory changes in the early stages of PD and obtain high diagnostic accuracy in more advanced stages of the disease.


Asunto(s)
Enfermedad de Parkinson , Trastornos Respiratorios , Humanos , Oscilometría , Enfermedad de Parkinson/complicaciones , Enfermedad de Parkinson/diagnóstico , Espirometría , Pulmón , Mecánica Respiratoria
3.
Yeast ; 39(1-2): 25-39, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34473375

RESUMEN

Insects interact with a wide variety of yeasts, often providing a suitable substrate for their growth. Some yeast-insect interactions are tractable models for understanding the relationships between the symbionts. Attine ants are prominent insects in the Neotropics and have performed an ancient fungiculture of mutualistic basidiomycete fungi for more than 55-65 million years. Yeasts gain access to this sophisticated mutualism, prompting diversity, ecological, and biotechnological studies in this environment. We review half a century research in this field, surveying for recurrent yeast taxa and their putative ecological roles in this environment. We found that previous studies mainly covered the yeast diversity from a small fraction of attine ants, being Saccharomycetales, Tremellales, and Trichosporonales as the most frequent yeast or yeast-like orders found. Apiotrichum, Aureobasidium, Candida, Cutaneotrichosporon, Debaryomyces, Meyerozyma, Papiliotrema, Rhodotorula, Trichomonascus, and Trichosporon are the most frequent recovered genera. On the other hand, studies of yeasts' ecological roles on attine ant-fungus mutualism only tapped the tip of the iceberg. Previous established hypotheses in the literature cover the production of lignocellulosic enzymes, chemical detoxification, and fungus garden protection. Some of these roles have parallels in biotechnological processes. In conclusion, the attine ant environment has a hidden potential for studying yeast biodiversity, ecology, and biotechnology, which has been particularly unexplored considering the vast diversity of fungus-growing ants.


Asunto(s)
Hormigas , Animales , Hormigas/microbiología , Biotecnología , Hongos , Filogenia , Simbiosis , Levaduras
4.
Nutr Neurosci ; 25(5): 1056-1065, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-33103611

RESUMEN

Fumonisins are naturally occurring mycotoxins that contaminate food for human and animal consumption. They have neurotoxic effects, but the mechanisms by which these toxins affect the nervous system are not fully known. In the present study, male Wistar rats were fed between 21 and 63 days of age with diets that contained fumonisins B1+B2 at 0, 1, and 4 mg/kg. The following variables were assessed: food consumption, growth, body weight gain, and blood parameters. Morphoquantitave analyses of the most metabolically active myenteric neurons were performed, detected by NADH-diaphorase activity. Nitrergic neurons were detected by NADPH-diaphorase activity. The fumonisin-containing diets did not significantly alter food consumption or the body or plasma parameters. These diets decreased the metabolic activity of jejunal myenteric neurons, reducing neuronal density of the most metabolic active neurons by 30.8% and the cell body area by 4.3%. The diets also decreased the cell body area of nitrergic neurons by 22.1%. The effects of fumonisin B1 on the respiratory metabolism of isolated mitochondria in the brain and liver were also assessed. A decrease in oxygen consumption up to a 29% in the brain and 38% in the liver was observed in mitochondrial isolates to which 50 µM fumonisin B1 was added. The decrease in respiratory activity that was triggered by exposure to fumonisins was related to the lower metabolic activity of myenteric neurons, which had a negative impact on neuroplasticity of the enteric nervous system.


Asunto(s)
Fumonisinas , Micotoxinas , Animales , Dieta , Fumonisinas/toxicidad , Masculino , Neuronas , Ratas , Ratas Wistar
5.
Vertex ; 33(158, oct.-dic.): 6-19, 2022 12 30.
Artículo en Español | MEDLINE | ID: mdl-36626610

RESUMEN

Objectives: To explore the frequency of sociodemographic, clinical, and therapeutic variables of the Inpatient Psychiatric Unit at the Italian Hospital of Buenos. Introduction: Considering that the Inpatient Psychiatric Unit functions within a General Metropolitan Community Hospital, referent both at the local and the international level, we deem it relevant to perform an updated characterization of the population admitted into our Unit. This is especially important given the changes presented since the approval of the National Mental Health Law N° 26.657. Materials and Methods: We performed an observational descriptive and analytic cross-sectional study, studying the patients admitted into the Inpatient Psychiatric Unit for a period of 12 consecutive months (from October 1st, 2018, to September 30th, 2019). Results: During the study period a total of 254 hospitalizations were registered. Mean Age: 51,85 years (S.D.=21,23), Median hospitalization time 22 days [IQR=14.00, 34.00], 31.5% of the admissions were involuntary. The most frequent cause of hospitalization was due to depressive episodes (32.7%), psychosis (22.8%), and dementia/behavioral symptoms (13%). 10.6% of the patients were admitted into our Unit after a suicide attempt. Discussion: The present study provides an updated analysis of the hospitalized population. It contributes to outlining the changes that have taken place over the last years, because of the new legislation. Conclusions: The description of the epidemiologic characteristics of the inpatient population in our setting is crucial to have a current situation diagnosis that allows us to develop health-policy strategies and an adequate allocation of resources.


Objetivo: Explorar la frecuencia de diferentes variables sociodemográficas, clínicas y terapéuticas en los pacientes internados en la Sala de Psiquiatría del Hospital Italiano de Buenos Aires (HIBA). Introducción: Considerando que la Sala de Psiquiatría del HIBA se encuentra emplazada en un hospital general privado metropolitano de comunidad, referente a nivel nacional e internacional, resulta relevante realizar una descripción actualizada de la población usuaria de dicho dispositivo a la luz de los cambios producto de la sanción de la Ley Nacional de Salud Mental N° 26.657. Materiales y métodos: Se realizó  un estudio observacional descriptivo y analítico de corte transversal de pacientes que fueron internados en la Sala de Psiquiatría del HIBA durante el período comprendido entre el 1 de octubre de 2018 hasta el 30 de septiembre de 2019 inclusive. Resultados: Durante el período del estudio se valoraron 254 internaciones. Edad promedio de 51,85 años (D.E.=21,23), Mediana de la duración de internación correspondió a 22 días [IQR=14.00, 34.00], siendo el 31.5% de las mismas de carácter involuntario. Los motivos de ingreso más frecuentes fueron: cuadros depresivos (32.7%), descompensación psicótica (22.8%) y demencia/síntomas conductuales (13%). El 10.6% de los pacientes ingresaron tras haber realizado una tentativa suicida. Discusión: El presente trabajo permite tener una noción actualizada de las características de los pacientes que atendemos en la Sala de Internación teniendo en cuenta los cambios en la legislación vigente y en la sociedad en su conjunto. Conclusiones: Caracterizar los determinantes epidemiológicos del patrón de internaciones psiquiátricas permite realizar diagnóstico de situación local y actualizado que favorecerá el desarrollar y repensar estrategias de planificación y gestión informadas.


Asunto(s)
Trastornos Mentales , Humanos , Argentina , Pacientes Internos , Hospitales Comunitarios , Hospitales Generales , Hospitalización
6.
Antonie Van Leeuwenhoek ; 114(6): 751-764, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33738647

RESUMEN

The leaf-cutter ant Acromyrmex balzani is responsible for causing important losses in reforestation areas, crops, and pastures, and is frequently found in the Brazilian savanna (Cerrado). So far, there is no information regarding the yeast communities that occur in their nests. Here, we evaluated the diversity, composition, and structure of yeast communities in both fungus gardens (FG) and external refuse dump (RD) of this ant species (Palmas, Tocantins, northern Brazil). A total of 720 yeasts were isolated, comprising 52 species distributed in 29 genera. The RDs have significantly richer and more diverse yeast communities than the fungus gardens, regardless of the season and the level of preservation in the area. The isolates produced a wide range of carbon polymer-degrading enzymes and were able to assimilate carbon-sources present in plant materials. We observed a different proportion of enzyme-producers and carbon-assimilation found in external refuse dump and fungus gardens from preserved and disturbed areas, suggesting that this interaction may vary depending on the environmental conditions. A. balzani nests in the savanna biome are a hotspot of yeast species with ecological, clinical, and biotechnological implications.


Asunto(s)
Hormigas , Animales , Ecosistema , Hongos , Pradera , Simbiosis
7.
Fish Shellfish Immunol ; 105: 350-358, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32717322

RESUMEN

Streptococcus agalactiae is considered the main bacterial pathogen in cultured Nile tilapia. Formaldehyde-inactivated vaccines are the most accepted method for prevention and control of the disease. However, alternative inactivation methods for S. agalactiae vaccines have not been fully explored. Recently, we developed a hydrogen peroxide-inactivated vaccine against S. agalactiae with moderate efficacy, with the possibility to improve vaccine efficacy by adding adjuvants. The current study compared the efficacy of aluminum hydroxide and Freund's incomplete adjuvant (FIA) incorporated into a novel hydrogen peroxide-inactivated intraperitoneal vaccine against S. agalactiae for Nile tilapia fingerlings. The relative percentage survival (RPS) for aluminum hydroxide-adjuvanted vaccine (59.3%), and FIA-adjuvanted vaccine (77.8%) were higher than the vaccine without adjuvant (40.7%). In addition, fish immunized with aluminum hydroxide-adjuvanted vaccine had significantly higher levels of specific antibodies than control fish at 4 weeks post vaccination (wpv). Blood lymphocytes counts showed a decrease in vaccinated groups when compared to control fish, suggesting white cells migration to the tissues where antigen presentation is ongoing. Fish that received FIA-adjuvanted vaccine exhibited persistence of adjuvant deposits on intraperitoneal surfaces for at least 4 wpv that may be related to its superior performance compared to aluminum hydroxide adjuvanted vaccine, which did not evidence any type of deposit at any sampling times. The results observed in this study demonstrate that hydrogen peroxide-inactivated vaccine administered with either aluminum hydroxide or FIA induce optimal levels of protection, with a superior performance for FIA vaccine, which could be a good alternative to conventional formaldehyde-inactivated vaccines against S. agalactiae, due to its shorter manufacture time, and less toxicity.


Asunto(s)
Adyuvantes Inmunológicos/administración & dosificación , Cíclidos , Enfermedades de los Peces/prevención & control , Peróxido de Hidrógeno/inmunología , Infecciones Estreptocócicas/veterinaria , Vacunas Estreptocócicas/inmunología , Streptococcus agalactiae/inmunología , Animales , Enfermedades de los Peces/microbiología , Infecciones Estreptocócicas/prevención & control , Vacunas de Productos Inactivados/inmunología
8.
Photochem Photobiol Sci ; 18(5): 1171-1184, 2019 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-30810155

RESUMEN

In this article, new fluorescent lipophilic based benzazoles were synthesized from the reaction between photoactive formyl derivatives and aliphatic amines followed by NaBH4 reduction with good yields. The photophysics of the benzazoles was investigated experimentally and theoretically. These compounds present absorption maxima in the UV region (∼339 nm) and fluorescence emission maxima in the cyan to green region with a large Stokes shift (∼175 nm) due to a proton transfer process in the excited state. Two fluorophores were successfully used as a proof of concept to produce stable photoactive liposomes prepared from phosphatidylcholine (PC) and were characterized by zeta potential, small angle X-ray scattering (SAXS), FTIR and UV-Vis experiments (turbidity). The scattering data indicate that the presence of compounds 20 and 23 reduces the overall surface charge of the PC vesicles, possibly due to the partial neutralization of phosphatidic acid and/or phosphatidylinositol phosphate by the amine groups, and they also modify the structural features of the assemblies, leading, in particular, to a reduction in the thickness of the hydrophobic inner segment (tt) of the liposomes. DFT and TD-DFT calculations were performed with the ωB97XD functional. Geometric analyses show that the 2-(2'-hydroxyphenyl)benzazolic planar portion allows an effective ππ* electronic transition. Additionally, the calculations indicate a small energy barrier to proton transfer. The results of the absorption and emission maxima show a slight solvent influence on the wavelengths.


Asunto(s)
Aminas , Teoría Funcional de la Densidad , Fluorescencia , Fosfatidilcolinas/química , Protones , Aminas/síntesis química , Aminas/química , Liposomas/síntesis química , Liposomas/química , Estructura Molecular , Procesos Fotoquímicos
9.
Crit Rev Biotechnol ; 38(4): 600-619, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29228814

RESUMEN

Antarctica is the coldest, windiest, and driest continent on Earth. In this sense, microorganisms that inhabit Antarctica environments have to be adapted to harsh conditions. Fungal strains affiliated with Ascomycota and Basidiomycota phyla have been recovered from terrestrial and marine Antarctic samples. They have been used for the bioprospecting of molecules, such as enzymes. Many reports have shown that these microorganisms produce cold-adapted enzymes at low or mild temperatures, including hydrolases (e.g. α-amylase, cellulase, chitinase, glucosidase, invertase, lipase, pectinase, phytase, protease, subtilase, tannase, and xylanase) and oxidoreductases (laccase and superoxide dismutase). Most of these enzymes are extracellular and their production in the laboratory has been carried out mainly under submerged culture conditions. Several studies showed that the cold-adapted enzymes exhibit a wide range in optimal pH (1.0-9.0) and temperature (10.0-70.0 °C). A myriad of methods have been applied for cold-adapted enzyme purification, resulting in purification factors and yields ranging from 1.70 to 1568.00-fold and 0.60 to 86.20%, respectively. Additionally, some fungal cold-adapted enzymes have been cloned and expressed in host organisms. Considering the enzyme-producing ability of microorganisms and the properties of cold-adapted enzymes, fungi recovered from Antarctic environments could be a prolific genetic resource for biotechnological processes (industrial and environmental) carried out at low or mild temperatures.


Asunto(s)
Enzimas/metabolismo , Proteínas Fúngicas/metabolismo , Hongos/metabolismo , Animales , Regiones Antárticas , Frío , Humanos
10.
Int J Syst Evol Microbiol ; 64(Pt 6): 2152-2158, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24682701

RESUMEN

Two novel species, Wickerhamiella kiyanii f.a., sp. nov. (type strain FB1-1DASP(T) = CBS 12905(T) = CBMAI 1613(T)) and Wickerhamiella fructicola f.a., sp. nov. (type strain H10Y(T) = CBS 12902(T) = CBMAI 1614(T)) are proposed in the Wickerhamiella clade (Saccharomycetes, Saccharomycetales) to accommodate three strains isolated from flowers and fruits typical of the Brazilian Atlantic rainforest. The novel status of these yeast species was established by sequence divergence observed in the D1/D2 domains of the LSU rRNA gene from the most closely related, described species as well as by phylogenetic analysis. Wickerhamiella kiyanii sp. nov. differs from its nearest phylogenetic neighbours W. pagnoccae CBS 12178(T), Candida jalapaonensis CBS 10935(T) and Candida drosophilae CBS 8459(T) by 2.2-4.2% in the D1/D2 sequences. By contrast, a sequence divergence of 13.2-13.8% was observed between W. fructicola sp. nov. and its closest, described phylogenetic relative Candida kazoui JCM 12558(T) and Candida hasegawae JCM 12559(T). Taxonomic descriptions of the two novel species are given.


Asunto(s)
Filogenia , Saccharomycetales/clasificación , Brasil , Campanulaceae/microbiología , ADN de Hongos/genética , Flores/microbiología , Frutas/microbiología , Genes de ARNr , Datos de Secuencia Molecular , Técnicas de Tipificación Micológica , Saccharomycetales/genética , Saccharomycetales/aislamiento & purificación , Análisis de Secuencia de ADN , Zingiberaceae/microbiología
11.
Antonie Van Leeuwenhoek ; 106(3): 475-87, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25012689

RESUMEN

Winged males of leaf-cutting ants are considered an ephemeral reproductive caste only produced before the mating flight season. Although much is known about the yeast diversity found in fungus gardens of attine ants, no study has focused on the yeasts associated with males of leaf-cutting ants. Here, we surveyed the yeasts on the integuments of males of Atta sexdens rubropilosa and assessed their potential role in the attine ant-microbe symbiosis. Using culture-dependent techniques, we found yeasts to be abundant on the integuments of males (54.5 %, n = 200 alates). A total of 242 yeast strains were obtained representing six orders, ten genera and 25 species. Strains of Aureobasidium, Cryptococcus, Hannaella and Rhodotorula were prevalent on the integuments and likely originated from the fungus garden of the parental nest or from the soil. The majority of strains (87.1 %) produced at least one of the evaluated enzymes: pectinase, polygalacturonase, cellulase, xylanase, ligninases and lipase. Aureobasidium pullulans accounted for the highest number of strains that produced all enzymes. In addition, yeasts showed the ability to assimilate the resulting oligosaccharides, supporting observations of other studies that yeasts may be involved in the plant biomass metabolism in the fungus gardens. Because winged males harbor several yeasts with putative functional roles, these fungi may take part and be beneficial in the microbial consortia of the new incipient nest.


Asunto(s)
Biodiversidad , Himenópteros/microbiología , Levaduras/clasificación , Levaduras/aislamiento & purificación , Animales , ADN de Hongos/química , ADN de Hongos/genética , Hidrolasas/análisis , Integumento Común/microbiología , Datos de Secuencia Molecular , Análisis de Secuencia de ADN , Levaduras/enzimología
12.
Acta Cytol ; 58(5): 495-500, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25358681

RESUMEN

OBJECTIVES: Endometrial cytology offers a reliable alternative to biopsy in endometrial cancer detection and it may be useful in obtaining material to study prognostic and predictive markers. Over the years, new sampling devices have been developed. Molecular alterations in endometrial cancers were previously described using formalin-fixed paraffin-embedded tissues with particular attention, in endometrioid carcinomas, to the PTEN-PI3K pathway. PTEN evaluation could be useful in endometrial carcinomas for selecting patients for target therapies. STUDY DESIGN: We studied 51 endometrial samples collected using the Endogyn device and 71 obtained with the Endoflower dispositive device, and processed using liquid-based cytology. Most of the cases were matched with a corresponding histological biopsy. The overall accuracy of Endoflower was 100%. Immunohistochemistry (IHC) and immunocytochemistry (ICC) for PTEN were performed using monoclonal antibody 6H2.1 from DAKO. RESULTS: The IHC showed PTEN-null glands in 4 cases. The same cancers were negative in ICC. Among the 10 carcinomas on cytology, PTEN-null glands were found in 1 case. All the normal endometrium control cases were positive in cytology and histology. CONCLUSIONS: Our results suggest that endometrial devices provide useful material for the diagnosis and evaluation of PTEN expression.


Asunto(s)
Biomarcadores de Tumor/genética , Carcinoma Endometrioide/diagnóstico , Neoplasias Endometriales/diagnóstico , Fosfohidrolasa PTEN/genética , Manejo de Especímenes/métodos , Adulto , Anciano , Anciano de 80 o más Años , Anticuerpos Monoclonales , Biopsia , Carcinoma Endometrioide/genética , Carcinoma Endometrioide/patología , Neoplasias Endometriales/genética , Neoplasias Endometriales/patología , Endometrio , Femenino , Expresión Génica , Humanos , Inmunohistoquímica , Persona de Mediana Edad , Manejo de Especímenes/instrumentación
13.
Plants (Basel) ; 13(10)2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38794408

RESUMEN

Negative effects of salt stress may be counteracted by adequate management of sulfated nutrition. Herein, we applied 3.50, 4.25, and 5.00 mM SO42- in a nutrient solution to counteract salt stress induced by 75 and 150 mM NaCl in cabbage cv. Royal. The increase in NaCl concentration from 75 to 150 mM reduced the contents of macronutrients and micronutrients in the shoot. When increasing from 3.50 to 4.25 mM SO42-, the contents of nitrogen (N), phosphorous (P), potassium (K), calcium (Ca), magnesium (Mg), and sulfur (S) in shoots were enhanced, at both concentrations of NaCl. Increasing from 3.50 to 4.25 mM SO42- enhanced iron (Fe), zinc (Zn), manganese (Mn), and sodium (Na) concentrations with 75 mM NaCl. With 150 mM NaCl, the increase from 3.50 to 4.25 mM SO42- enhanced the contents of Cu and Mn, but also those of Na. Chlorophylls a, b, and total decreased as the concentration of SO42- increased in plants treated with 150 mM NaCl. With 75 mM NaCl, carotenoid concentration had a positive relationship with SO42-. Hence, the 4.25 mM SO42- concentration increased the contents of macronutrients and micronutrients in the presence of 75 mM NaCl, while, with 150 mM NaCl, it improved the contents of macronutrients except K. The chlorophyll a/chlorophyll b ratio remained close to 3 when the plants were treated with 5.00 mM SO42-, regardless of NaCl. Similarly, this level of SO42- increased the concentration of carotenoids, which translated into reductions in the total chlorophyll/carotenoid ratios, indicating a protective effect of the photosynthetic apparatus. It is concluded that higher doses of sulfur favor the accumulation of nutrients and increase the concentration of carotenoids under salt stress.

14.
Environ Pollut ; 350: 123972, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38642794

RESUMEN

The billions of tons of plastic released into the environment mostly fragment into smaller particles that reach rivers and oceans, posing toxicity risks to aquatic organisms. As fish serve as excellent environmental indicator organisms, this study aims to comprehensively review and quantify published data regarding the abundance of microplastics (MPs) ingested by fish through scientometric analysis. Systematic analysis reveals that global aquatic ecosystems are contaminated by MPs, with the characteristics of these contaminants stemming from inadequate disposal management practices. The abundance of MPs was recorded in several fish species, notably Cyprinus carpio in natural environments and Danio rerio in controlled environments. According to the surveyed studies, laboratory experiments do not accurately represent the conditions found in natural environments. The results suggest that, in natural environments, the predominant colors of MPs are blue, black, and red. Fibers emerged as the most prevalent type, with polyethylene (PE) and polypropylene (PP) being the most frequently identified chemical compositions. On the other hand, laboratory studies showed that the spheres and fragments ingested were predominantly polystyrene (PS) green, followed by the colors blue and red. This discrepancy complicates drawing accurate conclusions regarding the actual effects of plastic particles on aquatic biota. Given the enduring presence of plastic in the environment, it is imperative to consider and implement environmental monitoring for effective, long-term management.


Asunto(s)
Monitoreo del Ambiente , Peces , Microplásticos , Contaminantes Químicos del Agua , Microplásticos/análisis , Animales , Contaminantes Químicos del Agua/análisis , Monitoreo del Ambiente/métodos , Ingestión de Alimentos , Plásticos/análisis
15.
Fungal Genet Biol ; 60: 2-8, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23872281

RESUMEN

Fungi are a diverse group of organisms with an overall global number of 1.5M up to 3.3M species on Earth. Besides their ecological roles as decomposers, fungi are important in several aspects of applied research. Here, we review how culture collections may promote the knowledge on diversity, conservation and biotechnological exploitation of fungi. The impact of fungi diversity on biotechnological studies is discussed. We point out the major roles of microbial repositories, including fungal preservation, prospecting, identification, authentication and supply. A survey on the World Data Center for Microorganisms (WDCM) powered by the World Federation for Culture Collections and on the Genetic Heritage Management Council (CGEN) database revealed that 46 Brazilian culture collections registered in these databases are dedicate to preserving fungi. Most of these culture collections are located in the Southeast of Brazil. This scenario also demonstrates that Brazil has many collections focused on fungal strains, but the lack of up-to-date information in WDCM as well as of a solid national platform for culture collections registration do not allow accurate assessment of fungal preservation.


Asunto(s)
Biotecnología , Hongos/clasificación , Biodiversidad , Brasil , Criopreservación
16.
Mycopathologia ; 175(5-6): 455-61, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23229615

RESUMEN

Several dematiaceous fungi frequently isolated from nature are involved in cases of superficial lesions to lethal cerebral infections. Antifungal susceptibility data on environmental and clinical isolates are still sparse despite the advances in testing methods. The objective of this study was to examine the activities of 5-flucytosine, amphotericin B, itraconazole, voriconazole and terbinafine against environmental isolates of Exophiala strains by minimum inhibition concentration (MIC) determination. The strains were obtained from hydrocarbon-contaminated soil, ant cuticle and fungal pellets from the infrabuccal pocket of attine gynes. Broth microdilution assay using M38-A2 reference methodology for the five antifungal drugs and DNA sequencing for fungal identification were applied. Terbinafine was the most active drug against the tested strains. It was observed that amphotericin B was less effective, notably against Exophiala spinifera, also studied. High MICs of 5-flucytosine against Exophiala dermatitidis occurred. This finding highlights the relevance of studies on the antifungal resistance of these potential opportunistic species. Our results also contribute to a future improvement of the standard methods to access the drug efficacy currently applied to black fungi.


Asunto(s)
Antifúngicos/farmacología , Microbiología Ambiental , Exophiala/efectos de los fármacos , Exophiala/aislamiento & purificación , ADN de Hongos/química , ADN de Hongos/genética , ADN Espaciador Ribosómico/química , ADN Espaciador Ribosómico/genética , Exophiala/clasificación , Exophiala/genética , Humanos , Pruebas de Sensibilidad Microbiana , Análisis de Secuencia de ADN
17.
Rev Invest Clin ; 65(2): 183-91, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23844537

RESUMEN

This position paper has been written by a multidisciplinary group of experts appointed by the National Institutes of Health (NIH). Its aim is to present the state of the art of knowledge about osteoporosis in Mexico. A review of the scientific papers in Mexico and information about diagnostics tools and treatment is discussed along with some research recommendations for the future.


Asunto(s)
Osteoporosis/epidemiología , Predicción , Humanos , México/epidemiología , Osteoporosis/prevención & control , Guías de Práctica Clínica como Asunto
18.
J Colloid Interface Sci ; 630(Pt A): 465-476, 2023 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-36265347

RESUMEN

For polymersome-based nanoreactor purposes, we herein present the synthesis and characterization of well-defined star amphiphilic copolymers composed of a beta-cyclodextrin (ßCD) core and seven poly(butylene oxide)-block-polyglycidol (PBO-PGL) arms per side (ßCD-(PBO-PGL)14). The self-assembly behavior of 14-armed ßCD-(PBO-PGL)14 and PGL-PBO-PGL (linear analogues without the ßCD segment) was investigated using scattering techniques for comparison. The morphologies, including vesicles and micelles, are governed by the hydrophobic-to-hydrophilic (weight) ratio, regardless of the polymer architecture (linear or star). Interestingly, despite notable differences in polymer conformation, the produced supramolecular structures were evidenced to be fairly similar on the structural point of view. We subsequently investigated the ion permeability of the membranes of the self-assemblies focusing on the impact of the presence of ßCD. The results demonstrated that the ßCD-containing vesicular membranes are less permeable to H+, compared with ßCD-free vesicular membranes. The presence of ßCD in planar membranes also influences the K+Cl- permeability to some extent. Thus, ßCD-containing membranes can be considered as potential candidates in designing nano-containers towards applications where precise changes in environmental pH are required.


Asunto(s)
Polímeros , beta-Ciclodextrinas , Polímeros/química , Micelas , beta-Ciclodextrinas/química , Interacciones Hidrofóbicas e Hidrofílicas , Conformación Molecular
19.
Front Cardiovasc Med ; 10: 1204232, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37416926

RESUMEN

Aims: Epidemiological surveillance has raised safety concerns for mRNA SARS-CoV-2-vaccination-related myocarditis. We aimed to analyze epidemiological, clinical and imaging findings associated with clinical outcomes in these patients in an international multi-center registry (NCT05268458). Methods and results: Patients with clinical and CMR diagnosis of acute myocarditis within 30 days after mRNA SARS-CoV-2-vaccination were included from five centers in Canada and Germany between 05/21 and 01/22. Clinical follow-up on persistent symptoms was collected. We enrolled 59 patients (80% males, mean age 29 years) with CMR-derived mild myocarditis (hs-Troponin-T 552 [249-1,193] ng/L, CRP 28 [13-51] mg/L; LVEF 57 ± 7%, LGE 3 [2-5] segments). Most common symptoms at baseline were chest pain (92%) and dyspnea (37%). Follow-up data from 50 patients showed overall symptomatic burden improvement. However, 12/50 patients (24%, 75% females, mean age 37 years) reported persisting symptoms (median interval 228 days) of chest pain (n = 8/12, 67%), dyspnea (n = 7/12, 58%), with increasing occurrence of fatigue (n = 5/12, 42%) and palpitations (n = 2/12, 17%). These patients had initial lower CRP, lower cardiac involvement in CMR, and fewer ECG changes. Significant predictors of persisting symptoms were female sex and dyspnea at initial presentation. Initial severity of myocarditis was not associated with persisting complaints. Conclusion: A relevant proportion of patients with mRNA SARS-CoV-2-vaccination-related myocarditis report persisting complaints. While young males are usually affected, patients with persisting symptoms were predominantly females and older. The severity of the initial cardiac involvement not predicting these symptoms may suggest an extracardiac origin.

20.
Plants (Basel) ; 12(6)2023 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-36986925

RESUMEN

Coffea arabica is one of the two most consumed coffee species in the world. Micropropagation through somatic embryogenesis has allowed the large-scale propagation of different coffee varieties. However, the regeneration of plants using this technique depends on the genotype. This study aimed to develop a protocol for the regeneration of C. arabica L. var. Colombia by somatic embryogenesis for its mass propagation. Foliar explants were cultured on Murashige and Skoog (MS) supplemented with different concentrations of 2,4-dichlorophenoxyacetic acid (2,4-D), 6-benzylaminopurine (BAP), and phytagel for inducing somatic embryogenesis. In total, 90% of the explants formed embryogenic calli with a culture medium containing 2 mg L-1 of 2,4-D, 0.2 mg L-1 BAP, and 2.3 g L-1 phytagel. The highest number of embryos per gram of callus (118.74) was obtained in a culture medium containing 0.5 mg L-1 2,4-D, 1.1 mg L-1 BAP, and 5.0 g L-1 phytagel. In total, 51% of the globular embryos reached the cotyledonary stage when they were cultured on the growth medium. This medium contained 0.25 mg L-1 BAP, 0.25 mg L-1 indoleacetic acid (IAA), and 5.0 g L-1 of phytagel. The mixture of vermiculite:perlite (3:1) allowed 21% of embryos to become plants.

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