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1.
Pediatr Res ; 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38942887

RESUMEN

BACKGROUND: Children attending school/daycare are at high risk of acute respiratory tract infections. EpiCorTM postbiotic, derived from yeast fermentate, has been demonstrated to improve immune function in adults, reducing the incidence of cold/flu-like or allergy symptoms. As such, studies are warranted in children as available pharmaceutical options have unwanted side effects. METHODS: Two-hundred and fifty-six children aged 4-12 years attending school/daycare were randomized to either EpiCor or Placebo for 84 days during the 2022-2023 flu season in Ontario, Canada. The Canadian Acute Respiratory Illness and Flu Scale (CARIFS) and study diary assessed the incidence and severity of cold/flu symptoms and the use of cold/flu medications. Adverse events were recorded. RESULTS: Total CARIFS severity scores, 'sore throat' and 'muscle aches or pains' symptom scores in the EpiCor group were significantly lower compared to Placebo during incidences of cold/flu (P ≤ 0.05). Participants taking Placebo were 1.73 times more likely to use cold/flu medication compared to those receiving EpiCor (P = 0.04). The incidence of cold/flu symptoms was not significantly different between groups. EpiCor was found to be safe and well-tolerated. CONCLUSIONS: EpiCor supplementation resulted in significantly lower cold/flu symptom severity and less cold/flu medication usage than Placebo demonstrating a beneficial effect on immune function in children. IMPACT: Children are at high risk of acquiring cold/flu infections and safe and efficacious mitigating regimens are lacking. Children supplemented daily with 500 mg EpiCorTM postbiotic derived from yeast fermentate had significantly lower overall cold/flu symptom severity, and severity of sore throat and muscle aches or pains over the 84-day supplementation period. EpiCor supplementation resulted in decreased use of traditional cold/flu medication. Daily supplementation with 500 mg of EpiCor for 84 days was safe and well tolerated by healthy children aged 4-12 years attending school or daycare.

2.
Pediatr Cardiol ; 2023 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-37344559

RESUMEN

Modern consensus panel guidelines recommend restriction from most organized sports for patients with moderate or severe aortic stenosis (AS). However, there is little published data on how frequently physicians deviate from guidelines, how well patients adhere to exercise restrictions, or the effect of restriction on patient-reported quality of life. In this study, we surveyed 93 subjects with AS and their cardiologists regarding participation in organized sports, physical activity, weightlifting, and exercise restriction. Subjects completed the pediatric quality of life inventory (PedsQL) and the pediatric cardiac quality of life inventory (PCQLI). We found that subjects with severe AS (n = 3) were commonly, but not universally, restricted from organized sports (n = 2, 66%). Subjects with moderate AS (n = 40) were rarely restricted from organized sports (n = 6, 17%). No physician-specific characteristics were associated with increased likelihood of recommending exercise restriction. Subjects were more likely to be restricted if they were older (16 years vs. 13 years, p 0.02) and had moderate versus mild AS (p 0.013). PCQLI scores for teens and young adults with AS (age 13-25) were lower than a comparison group of patients with mild congenital heart disease. For all age groups, the PedsQL social functioning score was lower for subjects with exercise restriction (p 0.052). In summary, cardiologists apply consensus guidelines leniently when restricting patients with moderate/severe AS from organized sports and weightlifting. Patients with AS routinely adhere to exercise restriction recommendations. Children and young adults with AS and exercise restriction have lower QOL scores in the social functioning domain.

3.
Magn Reson Med ; 85(5): 2359-2369, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33216412

RESUMEN

PURPOSE: Gamma-aminobutyric acid (GABA) abnormalities have been implicated in a range of neuropsychiatric disorders. Despite substantial interest in probing GABA in vivo, human imaging studies relying on magnetic resonance spectroscopy (MRS) have generally been hindered by technical challenges, including GABA's relatively low concentration and spectral overlap with other metabolites. Although past studies have shown moderate-to-strong test-retest repeatability and reliability of GABA within certain brain regions, many of these studies have been limited by small sample sizes. METHODS: GABA+ (macromolecular-contaminated) test-retest reliability and repeatability were assessed via a Meshcher-Garwood point resolved spectroscopy (MEGA-PRESS) MRS sequence in the rostral anterior cingulate cortex (rACC; n = 21) and dorsolateral prefrontal cortex (dlPFC; n = 20) in healthy young adults. Data were collected on a 3T scanner (Siemens Prisma, Siemens Healthcare, Erlangen, Germany) and GABA+ results were reported in reference to both total creatine (GABA+/tCr) and water (GABA+/water). RESULTS: Results showed strong test-retest repeatability (mean GABA+/tCr coefficient of variation [CV] = 4.6%; mean GABA+/water CV = 4.0%) and reliability (GABA+/tCr intraclass correlation coefficient [ICC] = 0.77; GABA+/water ICC = 0.87) in the dlPFC. The rACC showed acceptable (but comparatively lower) repeatability (mean GABA+/tCr CV = 8.0%; mean GABA+/water CV = 7.5%), yet low-moderate reliability (GABA+/tCr ICC = 0.40; GABA+/water ICC = 0.44). CONCLUSION: The present study found excellent GABA+ MRS repeatability and reliability in the dlPFC. The rACC showed inferior results, possibly because of a combination of shimming impedance and measurement error. These data suggest that MEGA-PRESS can be utilized to reliably distinguish participants based on dlPFC GABA+ levels, whereas the mixed results in the rACC merit further investigation.


Asunto(s)
Imagen por Resonancia Magnética , Ácido gamma-Aminobutírico , Alemania , Humanos , Espectroscopía de Resonancia Magnética , Reproducibilidad de los Resultados , Adulto Joven
4.
Int J Phytoremediation ; 20(1): 54-60, 2018 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-28598217

RESUMEN

The use of pyrolyzed carbon, biochar, as a soil amendment is of potential interest for improving phytoremediation of soil that has been contaminated by petroleum hydrocarbons. To examine this question, the research reported here compared the effects of biochar, plants (mesquite tree seedlings), compost and combinations of these treatments on the rate of biodegradation of oil in a contaminated soil and the population size of oil-degrading bacteria. The presence of mesquite plants significantly enhanced oil degradation in all treatments except when biochar was used as the sole amendment without compost. The greatest extent of oil degradation was achieved in soil planted with mesquite and amended with compost (44% of the light hydrocarbon fraction). Most probable number assays showed that biochar generally reduced the population size of the oil-degrading community. The results of this study suggest that biochar addition to petroleum-contaminated soils does not improve the rate of bioremediation. In contrast, the use of plants and compost additions to soil are confirmed as important bioremediation technologies.


Asunto(s)
Biodegradación Ambiental , Carbón Orgánico , Compostaje , Contaminantes del Suelo , Bacterias , Petróleo , Microbiología del Suelo
5.
J Environ Manage ; 222: 76-85, 2018 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-29804035

RESUMEN

Biochar can be an effective amendment for immobilizing heavy metals in contaminated soils but has variable effects depending on its chemical and physical properties and those of the treated soil. To investigate the range of biochar's effects on heavy metal accumulation in plants in responses to the variation of soil, biochar and plant, we carried out a meta-analysis of the literature that was published before March 2016. A total of 1298 independent observations were collected from 74 published papers. Results showed that across all studies, biochar addition to soils resulted in average decreases of 38, 39, 25 and 17%, respectively, in the accumulation of Cd, Pb, Cu and Zn in plant tissues. The effect of biochar on heavy metal concentrations in plants varied depending on soil properties, biochar type, plant species, and metal contaminants. The largest decreases in plant heavy metal concentrations occurred in coarse-textured soils amended with biochar. Biochar had a relatively small effect on plant tissue Pb concentrations, but a large effect on plant Cu concentrations when applied to alkaline soils. Plant uptake of Pb, Cu and Zn was less in soils with higher organic carbon contents. Manure-derived biochar was the most effective for reducing Cd and Pb concentrations in plants as compared to biochars derived from other feedstock. Biochar having a high pH and used at high application rates resulted in greater decreases in plant heavy metal uptake. The meta-analysis provides useful guidelines on the range of effects that can be anticipated for different biochar materials in different plant-soil systems.


Asunto(s)
Carbón Orgánico , Metales Pesados/farmacocinética , Plantas , Suelo , Contaminantes del Suelo
6.
FEMS Yeast Res ; 17(3)2017 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-28475763

RESUMEN

Canals are supramolecular complexes observed in the cell wall of Candida maltosa grown in the presence of hexadecane as a sole carbon source. Such structures were not observed in glucose-grown cells. Microscopic observations of cells stained with diaminobenzidine revealed the presence of oxidative enzymes in the canals. 4΄,6΄-diamino-2-phenylindole staining revealed that a substantial part of cellular polyphosphate was present in the cell wall of cells grown on hexadecane in condition of phosphate limitation. The content and chain length of polyphosphates were higher in hexadecane-grown cells than in glucose grown ones. The treatment of cells with yeast polyphosphatase PPX1 resulted in the decrease of the canal size. These data clearly indicated that polyphosphates are constituents of canals; they might play an important role in the canal structure and functioning.


Asunto(s)
Alcanos/farmacología , Candida/efectos de los fármacos , Pared Celular/efectos de los fármacos , 3,3'-Diaminobencidina , Ácido Anhídrido Hidrolasas/química , Candida/química , Candida/metabolismo , Candida/ultraestructura , Pared Celular/química , Pared Celular/metabolismo , Pared Celular/ultraestructura , Medios de Cultivo/química , Medios de Cultivo/farmacología , Diaminas , Glucosa/metabolismo , Glucosa/farmacología , Indoles , Microscopía Electrónica de Transmisión , Polifosfatos/química , Polifosfatos/metabolismo , Coloración y Etiquetado/métodos
7.
J Sci Food Agric ; 97(15): 5139-5145, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28436040

RESUMEN

BACKGROUND: Limited information is available about the effectiveness of biochar with plant growth-promoting rhizobacteria (PGPR) and compost. A greenhouse study was conducted to evaluate the effect of biochar in combination with compost and PGPR (Pseudomonas fluorescens) for alleviating water deficit stress. Both inoculated and un-inoculated cucumber seeds were sown in soil treated with biochar, compost and biochar + compost. Three water levels - field capacity (D0), 75% field capacity (D1) and 50% field capacity (D2) - were maintained. RESULTS: The results showed that water deficit stress significantly suppressed the growth of cucumber; however, synergistic use of biochar, compost and PGPR mitigated the negative impact of stress. At D2, the synergistic use of biochar, compost and PGPR caused significant increases in shoot length, shoot biomass, root length and root biomass, which were respectively 88, 77, 89 and 74% more than in the un-inoculated control. Significant improvements in chlorophyll and relative water contents as well as reduction in leaf electrolyte leakage demonstrated the effectiveness of this approach. Moreover, the highest population of P. fluorescens was observed where biochar and compost were applied together. CONCLUSION: These results suggest that application of biochar with PGPR and/or compost could be an effective strategy for enhancing plant growth under stress. © 2017 Society of Chemical Industry.


Asunto(s)
Producción de Cultivos/métodos , Cucumis sativus/crecimiento & desarrollo , Pseudomonas fluorescens/fisiología , Suelo/química , Biomasa , Carbón Orgánico/análisis , Carbón Orgánico/metabolismo , Producción de Cultivos/instrumentación , Cucumis sativus/metabolismo , Cucumis sativus/microbiología , Hojas de la Planta/crecimiento & desarrollo , Hojas de la Planta/metabolismo , Pseudomonas fluorescens/crecimiento & desarrollo , Microbiología del Suelo , Agua/análisis , Agua/metabolismo
8.
Yeast ; 33(2): 55-62, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26833628

RESUMEN

Electron-microscopic examinations have demonstrated local modifications in the cell wall of the yeast Candida maltosa grown on hexadecane. In our earlier studies, these modified sites, observed in other yeasts grown on oil hydrocarbons, were conventionally called 'canals'. The biochemical and cytochemical studies of C. maltosa have revealed a correlation between the formation of 'canals' and decrease in the amount of cell wall polysaccharides, glucan and mannan. The ultrathin sections and surface replicas have shown that the 'canals' are destroyed by pronase, thus indicating that a significant proportion of their content is represented by proteins. This finding was compatible with our earlier data on the localization of oxidative enzymes in 'canals' and possible participation of the 'canals' in the primary oxidation of hydrocarbons. A completely unexpected and intriguing phenomenon has been the appearance of 'canals' in the yeast C. maltosa under starvation conditions. Unlike the yeasts grown on hexadecane, mannan almost disappears in starving cells, while the quantity of glucan first decreases and then is restored to its initial level. The role of 'canals' in starving cells is as yet unclear; it is assumed that they acquire exoenzymes involved in the utilization of products of cell lysis in the starving population. In the future, 'canals' of starving cells will be studied in connection with their possible participation in apoptosis.


Asunto(s)
Alcanos/metabolismo , Candida/crecimiento & desarrollo , Pared Celular/ultraestructura , Candida/metabolismo , Candida/ultraestructura , Pared Celular/química , Medios de Cultivo , Hidrolasas/metabolismo , Mananos/metabolismo , Microscopía Electrónica
9.
Crit Rev Biotechnol ; 36(4): 639-51, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25665634

RESUMEN

Azo dyes and their intermediate degradation products are common contaminants of soil and groundwater in developing countries where textile and leather dye products are produced. The toxicity of azo dyes is primarily associated with their molecular structure, substitution groups and reactivity. To avoid contamination of natural resources and to minimize risk to human health, this wastewater requires treatment in an environmentally safe manner. This manuscript critically reviews biological treatment systems and the role of bacterial reductive and oxidative enzymes/processes in the bioremediation of dye-polluted wastewaters. Many studies have shown that a variety of culturable bacteria have efficient enzymatic systems that can carry out complete mineralization of dye chemicals and their metabolites (aromatic compounds) over a wide range of environmental conditions. Complete mineralization of azo dyes generally involves a two-step process requiring initial anaerobic treatment for decolorization, followed by an oxidative process that results in degradation of the toxic intermediates that are formed during the first step. Molecular studies have revealed that the first reductive process can be carried out by two classes of enzymes involving flavin-dependent and flavin-free azoreductases under anaerobic or low oxygen conditions. The second step that is carried out by oxidative enzymes that primarily involves broad specificity peroxidases, laccases and tyrosinases. This review focuses, in particular, on the characterization of these enzymes with respect to their enzyme kinetics and the environmental conditions that are necessary for bioreactor systems to treat azo dyes contained in wastewater.


Asunto(s)
Compuestos Azo/metabolismo , Proteínas Bacterianas/metabolismo , Colorantes/metabolismo , Oxidorreductasas/metabolismo , Contaminantes Químicos del Agua/metabolismo , Animales , Compuestos Azo/toxicidad , Bacterias/metabolismo , Biodegradación Ambiental , Colorantes/toxicidad , Humanos , Contaminantes Químicos del Agua/toxicidad
10.
Arch Microbiol ; 198(4): 379-87, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26860842

RESUMEN

Phosphate solubilization, 1-aminocyclopropane-1-carboxylic acid (ACC)-deaminase activity and production of siderophores and indole acetic acid (IAA) are well-known traits of plant growth-promoting rhizobacteria (PGPR). Here we investigated the expression of these traits as affected by salinity for three PGPR strains (Pseudomonas fluorescens, Bacillus megaterium and Variovorax paradoxus) at two salinity levels [2 and 5 % NaCl (w/v)]. Among the three strains, growth of B. megaterium was the least affected by high salinity. However, P. fluorescens was the best strain for maintaining ACC-deaminase activity, siderophore and IAA production under stressed conditions. V. paradoxus was the least tolerant to salts and had minimal growth and low PGPR trait expression under salt stress. Results of experiment examining the impact of bacterial inoculation on cucumber growth at three salinity levels [1 (normal), 7 and 10 dS m(-1)] revealed that P. fluorescens also had good rhizosphere competence and was the most effective for alleviating the negative impacts of salinity on cucumber growth. The results suggest that in addition to screening the PGPR regarding their effect on growth under salinity, PGPR trait expression is also an important aspect that may be useful for selecting the most promising PGPR bacterial strains for improving plant tolerance to salinity stress.


Asunto(s)
Fenómenos Fisiológicos Bacterianos , Cucumis sativus/microbiología , Cucumis sativus/fisiología , Tolerancia a la Sal/fisiología , Microbiología del Suelo , Bacillus megaterium/fisiología , Liasas de Carbono-Carbono , Cucumis sativus/efectos de los fármacos , Cucumis sativus/crecimiento & desarrollo , Regulación Bacteriana de la Expresión Génica , Genes Bacterianos/genética , Ácidos Indolacéticos/metabolismo , Pseudomonas fluorescens/fisiología , Salinidad , Sideróforos/genética , Cloruro de Sodio/farmacología
11.
Ecotoxicol Environ Saf ; 124: 42-49, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26454074

RESUMEN

Biological treatment of azo dyes commonly requires a combined anaerobic-aerobic process in which initial decolorization is achieved by reductive cleavage of azo bonds on the parent molecule. The present study was conducted to examine the relative importance of co-substrates for driving reductive decolorization of azo dyes by Shewanella sp. strain IFN4 using whole cells and enzyme assays. Results showed that the dye decolorization by strain IFN4 was faster in medium containing 1gL(-1) yeast extract (YE) as compared to nine other co-substrates. Moreover, only YE stimulated azoreductase activity (increased from 1.32 to 4.19U/mg protein). Increasing the level of YE up to 8gL(-)(1) resulted into 81% decolorization of the dye in 1h along with an increase in azoreductase activity up to 6.16U/mg protein. Among the components of YE, only riboflavin stimulated the decolorization process as well as enzyme activity. Moreover, strain IFN4 demonstrated flavin reductase activity, and a significant correlation (r(2)=0.98) between flavin reduction and dye reduction by this strain emphasized the involvement of flavin compounds in the decolorization process. The results of this study show that YE serves both as a source of reducing equivalents and an electron shuttle for catalyzing dye reduction.


Asunto(s)
Compuestos Azo/metabolismo , Colorantes/metabolismo , Mezclas Complejas/metabolismo , Shewanella/metabolismo , Levaduras/química , NADH NADPH Oxidorreductasas/metabolismo , Nitrorreductasas , Oxidación-Reducción
12.
Environ Sci Technol ; 49(9): 5425-33, 2015 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-25853431

RESUMEN

Carbon isotopic analysis and molecular-based methods were used in conjunction with geochemical data sets to assess the dechlorination of pentachlorophenol (PCP) when coupled to biogeochemical processes in a mangrove soil having no prior history of anthropogenic contamination. The PCP underwent 96% dechlorination in soil amended with acetate, compared to 21% dehalogenation in control soil. Carbon isotope analysis of residual PCP demonstrated an obvious enrichment of 13C (εC, -3.01±0.1%). Molecular and statistical analyses demonstrated that PCP dechlorination and Fe(III) reduction were synergistically combined electron-accepting processes. Microbial community analysis further suggested that enhanced dechlorination of PCP during Fe(III) reduction was mediated by members of the multifunctional family of Geobacteraceae. In contrast, PCP significantly suppressed the growth of SO4(2-) reducers, which, in turn, facilitated the production of CH4 by diversion of electrons from SO4(2-) reduction to methanogenesis. The integrated data regarding stoichiometric alterations in this study gives direct evidence showing PCP, Fe(III), and SO4(2-) reduction, and CH4 production are coupled microbial processes during changes in soil redox.


Asunto(s)
Pentaclorofenol/química , Microbiología del Suelo , Contaminantes del Suelo/química , Acetatos/química , Isótopos de Carbono , China , Deltaproteobacteria/metabolismo , Compuestos Férricos , Halogenación , Hierro/metabolismo , Metano/metabolismo , Oxidación-Reducción , Pentaclorofenol/metabolismo , Suelo/química , Contaminantes del Suelo/metabolismo , Sulfatos/metabolismo
13.
Ecotoxicol Environ Saf ; 120: 163-8, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26074308

RESUMEN

The aim of this study was to examine the stability of structurally different azo dyes in soil and their impact on the microbial community composition by analyzing phospholipid fatty acid (PLFA) profiles. Sterile and non-sterile soils were amended with three azo dyes, including: Direct Red 81, Reactive Black 5 and Acid Yellow 19 at 160mgkg(-1) soil. The results showed that the azo dyes were quite stable and that large amounts of these dyes ranging from 17.3% to 87.5% were recoverable from the sterile and non-sterile soils after 14 days. The maximum amount of dye was recovered in the case of Direct Red 81. PLFA analysis showed that the azo dyes had a significant effect on microbial community structure. PLFA concentrations representing Gram-negative bacteria in dye-amended soil were substantially less as compared to the PLFA concentration of Gram-positive bacteria. Acid Yellow 19 dye had almost similar effects on the PLFA concentrations representing bacteria and fungi. In contrast, Reactive Black 5 had a greater negative effect on fungal PLFA than that on bacterial PLFA, while the opposite was observed in the case of Direct Red 81. To our knowledge, this is the first study reporting the stability of textile azo dyes in soil and their effects on soil microbial community composition.


Asunto(s)
Compuestos Azo/química , Ácidos Grasos/química , Fosfolípidos/química , Microbiología del Suelo , Contaminantes del Suelo/química , Textiles , Bacterias/química , Bacterias/efectos de los fármacos , Hongos/química , Hongos/efectos de los fármacos , Suelo/química
14.
Water Environ Res ; 87(7): 579-86, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26163493

RESUMEN

In this study, effect of various metal ions and salts on biodecolorization of Reactive black-5, azoreductase activity, and growth of Shewanella sp. strain IFN4 was evaluated. Among the tested metals, Cr²âº, Pb(²âº, Ni²âº, Fe²âº, and Mn²âº did not inhibit the biodecolorization of reactive black-5, azoreductase activity and bacterial growth. Three metals (Cu²âº, Zn²âº, and Co²âº) delayed the decolorization process without completely inhibiting the reaction and also suppressed the bacterial growth. However, no dye decolorization was observed in the presence of Cd²âº (10 mg L⁻¹). Furthermore, bacterium decolorized the dye at high concentration (15 mg L⁻¹) of mixed metal ions. Strain IFN4 was also able to decolorize the dye at 50 g NaCl L⁻¹ and 60 g Na2SO4 L⁻¹. NaCl was found to be more inhibitory to bacterial growth than Na2SO4and the reverse was observed for azoreductase activity. These findings suggest that strain IFN4 could be used in designing a bioreactor for the treatment of textile effluent.


Asunto(s)
Metales/farmacología , Naftalenosulfonatos/química , Shewanella/metabolismo , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/metabolismo , Biodegradación Ambiental , Relación Dosis-Respuesta a Droga , Metales/administración & dosificación , NADH NADPH Oxidorreductasas/metabolismo , Nitrorreductasas , Shewanella/efectos de los fármacos , Shewanella/enzimología , Factores de Tiempo
15.
World J Microbiol Biotechnol ; 31(2): 415-33, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25601371

RESUMEN

Many legumes have been selected as model plants to degrade organic contaminants with their special associated rhizosphere microbes in soil. However, the function of root nodules during microbe-assisted phytoremediation is not clear. A pot study was conducted to examine phenanthrene (PHE) utilizing bacteria associated with root nodules and the effects of cowpea root nodules on phytoremediation in two different types of soils (freshly contaminated soil and aged contaminated soil). Cowpea nodules in freshly-contaminated soil showed less damage in comparison to the aged-contaminated soil, both morphologically and ultra-structurally by scanning electron microscopy. The study of polycyclic aromatic hydrocarbon (PAH) attenuation conducted by high performance liquid chromatography revealed that more PAH was eliminated from liquid culture around nodulated roots than nodule-free roots. PAH sublimation and denaturation gradient gel electrophoresis were applied to analyze the capability and diversity of PAH degrading bacteria from the following four parts of rhizo-microzone: bulk soil, root surface, nodule surface and nodule inside. The results indicated that the surface and inside of cowpea root nodules were colonized with bacterial consortia that utilized PHE. Our results demonstrated that root nodules not only fixed nitrogen, but also enriched PAH-utilizing microorganisms both inside and outside of the nodules. Legume nodules may have biotechnological values for PAH degradation.


Asunto(s)
Bacterias/crecimiento & desarrollo , Fabaceae/crecimiento & desarrollo , Fabaceae/microbiología , Consorcios Microbianos , Fenantrenos/metabolismo , Nódulos de las Raíces de las Plantas/microbiología , Biodegradación Ambiental , Medios de Cultivo/química , Fabaceae/ultraestructura , Microscopía Electrónica de Rastreo , Microbiología del Suelo , Contaminantes del Suelo/metabolismo
16.
J Environ Sci (China) ; 33: 45-59, 2015 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-26141877

RESUMEN

Biodegradation of polycyclic aromatic hydrocarbons (PAHs) is normally limited by their low solubility and poor bioavailability. Prior research suggests that biosurfactants are synthesized as intermediates during the production of mucilage at the root tip. To date the effects of mucilage on PAH degradation and microbial community response have not been directly examined. To address this question, our research compared 3 cowpea breeding lines (Vigna unguiculata) that differed in mucilage production for their effects on phenanthrene (PHE) degradation in soil. The High Performance Liquid Chromatography results indicated that the highest PHE degradation rate was achieved in soils planted with mucilage producing cowpea line C1, inoculated with Bradyrhizobium, leading to 91.6% PHE disappearance in 5 weeks. In root printing tests, strings treated with mucilage and bacteria produced larger clearing zones than those produced on mucilage treated strings with no bacteria or bacteria inoculated strings. Experiments with 14C-PHE and purified mucilage in soil slurry confirmed that the root mucilage significantly enhanced PHE mineralization (82.7%), which is 12% more than the control treatment without mucilage. The profiles of the PHE degraders generated by Denaturing gradient gel electrophoresis suggested that cowpea C1, producing a high amount of root mucilage, selectively enriched the PHE degrading bacteria population in rhizosphere. These findings indicate that root mucilage may play a significant role in enhancing PHE degradation and suggests that differences in mucilage production may be an important criterion for selection of the best plant species for use in phytoremediation of PAH contaminated soils.


Asunto(s)
Bacterias/efectos de los fármacos , Fabaceae/química , Fenantrenos/química , Exudados de Plantas/farmacología , Raíces de Plantas/química , Bacterias/genética , Biodegradación Ambiental , Fenantrenos/metabolismo , Filogenia , Exudados de Plantas/química , Microbiología del Suelo , Contaminantes del Suelo/química , Contaminantes del Suelo/metabolismo
17.
Alcohol Clin Exp Res ; 38(7): 1955-64, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24961871

RESUMEN

BACKGROUND: The brain undergoes dynamic and requisite changes into the early 20s that are associated with improved cognitive efficiency, particularly in prefrontal regions that are still undergoing neuromaturation. As alcohol consumption is typically initiated and progresses to binge drinking (BD) during this time, the objective of the present study was to investigate the impact of binge alcohol consumption on frontal lobe cortical thickness in emerging adults. METHODS: Twenty-three binge drinking (11 females, mean age 22.0 ± 1.2) and 31 light drinking (15 females, mean age 21.5 ± 1.6) emerging adults underwent high-resolution magnetic resonance imaging at 3 Tesla. Cortical surface reconstruction and thickness estimation were performed using FreeSurfer for 3 a priori brain regions of interest: bilateral anterior cingulate cortex (ACC), posterior cingulate cortex (PCC), and parieto-occipital sulcus (POS). Cortical thickness measurements were then compared between binge drinker (BD) and light drinker (LD) groups. RESULTS: Cortical thickness was significantly lower in BD than LD in the right middle ACC (mid-ACC; p ≤ 0.05) and in the left dorsal PCC (dPCC; p ≤ 0.01). No significant differences in cortical thickness were observed in the POS. Cortical thickness in the mid-ACC correlated negatively with higher quantity and frequency of drinks consumed (p < 0.01) and positively with the number of days elapsed since most recent use (p < 0.05). Furthermore, less cortical thickness in the mid-ACC in the BD group alone correlated with reported patterns of high quantity and frequency of alcohol consumption (p ≤ 0.05). CONCLUSIONS: Findings suggest that past and recent patterns of intermittent heavy alcohol consumption are associated with less frontal cortical thickness (i.e., "thinness") of the right mid-ACC and left dPCC in emerging adults, but not the POS. While cortical thinness could have predated binge drinking, this pattern of maladaptive consumption may have acute neurotoxic effects that interfere with the finalization of neuromaturational processes in the vulnerable frontal cortex, resulting in increased microarchitectural pruning.


Asunto(s)
Consumo Excesivo de Bebidas Alcohólicas/patología , Consumo Excesivo de Bebidas Alcohólicas/psicología , Conducta de Ingestión de Líquido , Giro del Cíngulo/patología , Atrofia/patología , Estudios de Casos y Controles , Femenino , Lóbulo Frontal/patología , Humanos , Imagen por Resonancia Magnética , Masculino , Neuroimagen , Adulto Joven
18.
Alcohol Clin Exp Res ; 38(4): 969-79, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24512596

RESUMEN

BACKGROUND: Binge alcohol consumption is associated with multiple neurobiological consequences, including altered neurophysiology, brain structure, and functional activation. Magnetic resonance spectroscopy (MRS) studies have demonstrated neurochemical alterations in the frontal lobe of alcohol users, although most studies focused on older, alcohol-dependent subjects. METHODS: In this study, neurochemical data were acquired using MRS at 4.0 Tesla from emerging adults (18 to 24 years old) who were binge alcohol drinkers (BD, n = 23) or light drinkers (LD, n = 31). Since binge drinking is also associated with increased prevalence of experiencing an alcohol-induced blackout, BD were stratified into alcohol-induced blackout (BDBO) and non-blackout (BDN) groups. RESULTS: Overall, BD had significantly lower gamma amino-butyric acid (GABA) and N-acetyl-aspartate (NAA) in the anterior cingulate cortex (ACC) than LD. When stratified by blackout history, BDBO also had lower ACC glutamate (Glu) than LD. No group differences in MRS metabolites were observed in the parietal-occipital cortex. Lower ACC GABA and Glu remained significant after accounting for lower gray matter content in BD, however, NAA differences were no longer evident. In addition, low ACC GABA levels were associated with greater alcohol use consequences, and worse response inhibition and attention/mental flexibility in BD. CONCLUSIONS: These data indicate that binge drinking affects frontal lobe neurochemistry, more so in those who had experienced an alcohol-induced blackout. Characterization of the neurochemical profiles associated with binge alcohol consumption and blackout history may help identify unique risk factors for the later manifestation of alcohol abuse and dependence, in young individuals who are heavy, frequent drinkers, but who do not meet the criteria for alcohol abuse disorders.


Asunto(s)
Trastornos Inducidos por Alcohol/metabolismo , Amnesia Retrógrada/metabolismo , Consumo Excesivo de Bebidas Alcohólicas/metabolismo , Giro del Cíngulo/química , Giro del Cíngulo/metabolismo , Adolescente , Trastornos Inducidos por Alcohol/diagnóstico , Amnesia Retrógrada/inducido químicamente , Amnesia Retrógrada/diagnóstico , Consumo Excesivo de Bebidas Alcohólicas/diagnóstico , Femenino , Humanos , Espectroscopía de Resonancia Magnética/métodos , Masculino , Encuestas y Cuestionarios , Adulto Joven
19.
Microb Ecol ; 68(3): 567-74, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24889284

RESUMEN

Bacterial communities associated with tree canopies have been shown to be specific to their plant hosts, suggesting that plant species-specific traits may drive the selection of microbial species that comprise their microbiomes. To further examine the degree to which the plant taxa drive the assemblage of bacterial communities in specific plant microenvironments, we evaluated bacterial community structures associated with the phyllosphere, dermosphere, and rhizosphere of seven tree species representing three orders, four families and four genera of plants from a pristine Dense Ombrophilous Atlantic forest in Brazil, using a combination of PCR-DGGE of 16S rRNA genes and clone library sequencing. Results indicated that each plant species selected for distinct bacterial communities in the phyllosphere, dermosphere, and rhizosphere, and that the bacterial community structures are significantly related to the plant taxa, at the species, family, and order levels. Further characterization of the bacterial communities of the phyllosphere and dermosphere of the tree species showed that they were inhabited predominantly by species of Gammaproteobacteria, mostly related to Pseudomonas. In contrast, the rhizosphere bacterial communities showed greater species richness and evenness, and higher frequencies of Alphaproteobacteria and Acidobacteria Gp1. With individual tree species each selecting for their specific microbiomes, these findings greatly increase our estimates of the bacterial species richness in tropical forests and provoke questions concerning the ecological functions of the microbial communities that exist on different plant parts.


Asunto(s)
Bacterias/clasificación , Filogenia , Rizosfera , Microbiología del Suelo , Árboles/microbiología , Bacterias/genética , Brasil , ADN Bacteriano/genética , Bosques , Datos de Secuencia Molecular , Corteza de la Planta/microbiología , Hojas de la Planta/microbiología , Raíces de Plantas/genética , ARN Ribosómico 16S/genética , Especificidad de la Especie
20.
Depress Anxiety ; 31(2): 115-23, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23861191

RESUMEN

BACKGROUND: Increased reactivity of the insular cortex and decreased activity of the dorsal anterior cingulate cortex (ACC) are seen in functional imaging studies of posttraumatic stress disorder (PTSD), and may partly explain the persistent fear and anxiety proneness that characterize the disorder. A possible neurochemical correlate is altered function of the inhibitory neurotransmitter gamma-aminobutyric acid (GABA). We report results from what we believe is the first study applying proton magnetic resonance spectroscopy ((1) H-MRS) to measure brain GABA in PTSD. METHODS: Thirteen adults with DSM-IV PTSD and 13 matched healthy control subjects underwent single voxel (1) H-MRS at 4 Tesla. GABA was measured in the right anterior insula and dorsal ACC, using Mescher-Garwood Point-Resolved Echo Spectroscopy Sequence (MEGAPRESS) spectral editing. Subjects were interviewed with the Structured Clinical Interview for DSM-IV and the Clinician Administered PTSD Scale, and also completed the State and Trait Anxiety Inventory. RESULTS: Insula GABA was significantly lower in PTSD subjects than in controls, and dorsal ACC GABA did not differ significantly between the groups. Insula GABA was not significantly associated with severity of PTSD symptoms. However, lower insula GABA was associated with significantly higher state and trait anxiety in the subject sample as a whole. CONCLUSIONS: PTSD is associated with reduced GABA in the right anterior insula. This preliminary evidence of the (1) H-MRS GABA metabolite as a possible biomarker of PTSD encourages replication in larger samples and examination of relations with symptom dimensions. Future studies also should examine whether insula GABA is a marker of anxiety proneness, cutting across clinical diagnostic categories.


Asunto(s)
Mapeo Encefálico/métodos , Encéfalo/metabolismo , Espectroscopía de Resonancia Magnética/métodos , Trastornos por Estrés Postraumático/metabolismo , Ácido gamma-Aminobutírico/metabolismo , Adolescente , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
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