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1.
Nature ; 604(7905): 280-286, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35418631

RESUMEN

Multijunction solar cells can overcome the fundamental efficiency limits of single-junction devices. The bandgap tunability of metal halide perovskite solar cells renders them attractive for multijunction architectures1. Combinations with silicon and copper indium gallium selenide (CIGS), as well as all-perovskite tandem cells, have been reported2-5. Meanwhile, narrow-gap non-fullerene acceptors have unlocked skyrocketing efficiencies for organic solar cells6,7. Organic and perovskite semiconductors are an attractive combination, sharing similar processing technologies. Currently, perovskite-organic tandems show subpar efficiencies and are limited by the low open-circuit voltage (Voc) of wide-gap perovskite cells8 and losses introduced by the interconnect between the subcells9,10. Here we demonstrate perovskite-organic tandem cells with an efficiency of 24.0 per cent (certified 23.1 per cent) and a high Voc of 2.15 volts. Optimized charge extraction layers afford perovskite subcells with an outstanding combination of high Voc and fill factor. The organic subcells provide a high external quantum efficiency in the near-infrared and, in contrast to paradigmatic concerns about limited photostability of non-fullerene cells11, show an outstanding operational stability if excitons are predominantly generated on the non-fullerene acceptor, which is the case in our tandems. The subcells are connected by an ultrathin (approximately 1.5 nanometres) metal-like indium oxide layer with unprecedented low optical/electrical losses. This work sets a milestone for perovskite-organic tandems, which outperform the best p-i-n perovskite single junctions12 and are on a par with perovskite-CIGS and all-perovskite multijunctions13.


Asunto(s)
Compuestos de Calcio , Indio , Cobre , Óxidos , Titanio
3.
Nat Commun ; 13(1): 393, 2022 01 19.
Artículo en Inglés | MEDLINE | ID: mdl-35046411

RESUMEN

The fate of hematopoietic stem cells (HSCs) can be directed by microenvironmental factors including extracellular calcium ion concentration ([Ca2+]e), but the local [Ca2+]e around individual HSCs in vivo remains unknown. Here we develop intravital ratiometric analyses to quantify the absolute pH and [Ca2+]e in the mouse calvarial bone marrow, taking into account the pH sensitivity of the calcium probe and the wavelength-dependent optical loss through bone. Unexpectedly, the mean [Ca2+]e in the bone marrow (1.0 ± 0.54 mM) is not significantly different from the blood serum, but the HSCs are found in locations with elevated local [Ca2+]e (1.5 ± 0.57 mM). With aging, a significant increase in [Ca2+]e is found in M-type cavities that exclusively support clonal expansion of activated HSCs. This work thus establishes a tool to investigate [Ca2+]e and pH in the HSC niche with high spatial resolution and can be broadly applied to other tissue types.


Asunto(s)
Médula Ósea/diagnóstico por imagen , Médula Ósea/metabolismo , Calcio/metabolismo , Microscopía Intravital , Envejecimiento/metabolismo , Animales , Benzopiranos/química , Médula Ósea/irrigación sanguínea , Remodelación Ósea , Microambiente Celular , Fluorescencia , Células Madre Hematopoyéticas/metabolismo , Concentración de Iones de Hidrógeno , Ratones Endogámicos C57BL , Naftoles/química , Rodaminas/química
4.
Braz. j. biol ; 79(2): 191-200, Apr.-June 2019. tab, graf
Artículo en Inglés | LILACS | ID: biblio-989448

RESUMEN

Abstract The hygienic and sanitary control in Food and Nutrition Units (FNU) is considered a standard procedure to produce adequate meals and reduce the risk of foodborne diseases and hospital infections. This study aimed to evaluate the isolation and identification of bacteria from equipment and food contact surfaces in a hospital FNU as well as to evaluate the sanitary condition. Likewise, it was analyzed the adhesion of the microorganisms on polyethylene cutting boards. The presence of aerobic mesophilic microorganisms, yeasts, molds, coagulase-positive staphylococci, coliform and fecal coliform, and Escherichia coli were analyzed on eating tables, countertop surfaces and cutting boards used for meat or vegetable handling, and equipment such as microwaves and refrigerators. The molecular identification it was done by 16S rRNA gene sequencing. The adhesion of the microorganisms (biofilm formation) on meat and vegetable cutting boards was also evaluated by scanning electron microscopy. The results showed high numbers of all microorganisms, except for E. coli , which was not observed in the samples. The molecular analysis identified species of the Enterobacteriaceae family and species of the Pseudomonadaceae family. Scanning electron microscopy analyses revealed bacterial adhesion on the cutting board surfaces. The results obtained in this study indicated that the hygienic conditions of surfaces like plastic cutting boards and equipment in this hospital FNU were inadequate. The achievement and application of standard operating procedures could positively help in the standardization of sanitary control, reducing the microbial contamination and providing a safe food to hospitalized patients.


Resumo O controle higiênico e sanitário nas Unidades de Alimentação e Nutrição (UAN) é considerado um procedimento padrão para produzir refeições adequadas e reduzir o risco de doenças transmitidas pelos alimentos e infecções hospitalares. Este estudo teve como objetivo isolar e identificar bactérias de equipamentos e superfícies de contato com alimentos em uma UAN hospitalar, bem como avaliar a condição sanitária. Do mesmo modo, analisou-se a adesão dos micro-organismos em tábuas de corte de polietileno. A presença de micro-organismos aeróbios mesófilos, leveduras, fungos, Sthapylococcus coagulase-positivos, coliformes, coliformes fecais e Escherichia coli foi analisadas na superfície de mesas do refeitório, superfícies de bancada e tábuas de corte usadas para manuseio de carne ou vegetais e, em equipamentos como micro-ondas e refrigeradores. A identificação molecular foi feita pelo sequenciamento do gene 16S rRNA. A adesão dos micro-organismos (formação de biofilmes) em tábuas de corte de carne e de vegetais também foi avaliada por microscopia eletrônica de varredura. Os resultados mostraram elevada contagem para todos os micro-organismos analisados, exceto para E. coli, a qual não foi observada nas amostras. A análise molecular identificou espécies da família Enterobacteriaceae e Pseudomonadaceae. A análise de microscopia eletrônica de varredura revelaram adesão bacteriana nas superfícies das placsa de corte. Os resultados obtidos neste estudo indicaram que as condições higiênicas das superfícies e de equipamentos nesta UAN hospitalar estavam inadequadas. A aplicação de procedimentos operacionais padrão poderia auxiliar positivamente na padronização do controle higiênico-sanitário, reduzindo a contaminação microbiana e fornecendo um alimento seguro para pacientes hospitalizados.


Asunto(s)
Humanos , Microbiología Ambiental , Tipificación Molecular , Microbiología de Alimentos , Servicio de Alimentación en Hospital/tendencias , Bacterias/aislamiento & purificación , Bacterias/clasificación , Bacterias/genética , Biopelículas , Hongos/aislamiento & purificación , Hongos/clasificación , Hongos/genética
5.
Braz J Biol ; 79(2): 191-200, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30365634

RESUMEN

The hygienic and sanitary control in Food and Nutrition Units (FNU) is considered a standard procedure to produce adequate meals and reduce the risk of foodborne diseases and hospital infections. This study aimed to evaluate the isolation and identification of bacteria from equipment and food contact surfaces in a hospital FNU as well as to evaluate the sanitary condition. Likewise, it was analyzed the adhesion of the microorganisms on polyethylene cutting boards. The presence of aerobic mesophilic microorganisms, yeasts, molds, coagulase-positive staphylococci, coliform and fecal coliform, and Escherichia coli were analyzed on eating tables, countertop surfaces and cutting boards used for meat or vegetable handling, and equipment such as microwaves and refrigerators. The molecular identification it was done by 16S rRNA gene sequencing. The adhesion of the microorganisms (biofilm formation) on meat and vegetable cutting boards was also evaluated by scanning electron microscopy. The results showed high numbers of all microorganisms, except for E. coli , which was not observed in the samples. The molecular analysis identified species of the Enterobacteriaceae family and species of the Pseudomonadaceae family. Scanning electron microscopy analyses revealed bacterial adhesion on the cutting board surfaces. The results obtained in this study indicated that the hygienic conditions of surfaces like plastic cutting boards and equipment in this hospital FNU were inadequate. The achievement and application of standard operating procedures could positively help in the standardization of sanitary control, reducing the microbial contamination and providing a safe food to hospitalized patients.


Asunto(s)
Microbiología Ambiental , Microbiología de Alimentos , Servicio de Alimentación en Hospital/normas , Tipificación Molecular , Bacterias/clasificación , Bacterias/genética , Bacterias/aislamiento & purificación , Biopelículas , Hongos/clasificación , Hongos/genética , Hongos/aislamiento & purificación , Humanos
6.
Braz. j. biol ; 78(3): 449-456, Aug. 2018. tab, graf
Artículo en Inglés | LILACS | ID: biblio-951579

RESUMEN

Abstract Edaphic macrofauna must be better studied if we want to take advantage of their full potential for the restoration of tropical ecosystems. We investigated changes in edaphic macrofauna density and diversity along a secondary succession chronosequence in the Atlantic Forest. Our results show some clear patterns of change in soil macrofauna along the chronosequence. Density did not increase along secondary succession, but was correlated with canopy cover. Diversity was characterized by high dominance of social insects and evenness among other groups. We conclude soil macrofauna has a high capacity to recolonize young forests and that its recovery is considerably fast compared to other ecosystem transformations.


Resumo A macrofauna edáfica deve ser mais bem estudada se quisermos aproveitar todo o seu potencial para a restauração de ecossistemas tropicais. Nós investigamos as mudanças de densidade e diversidade da macrofauna edáfica em uma cronossequência durante a sucessão secundária na Mata Atlântica. Nossos resultados mostram padrões claros de mudança. A densidade não aumentou ao longo da sucessão secundária, mas foi correlacionada com a cobertura de dossel. A diversidade foi caracterizada pela alta dominância de insetos sociais e equidade entre os demais grupos. Nós concluímos que a macrofauna edáfica tem alta capacidade de recolonizar florestas jovens e que sua recuperação é relativamente rápida se comparada a outras transformações ecossistêmicas.


Asunto(s)
Animales , Microbiología del Suelo/normas , Árboles/crecimiento & desarrollo , Adaptación Fisiológica , Bosques , Conservación de los Recursos Naturales , Restauración y Remediación Ambiental , Suelo/química , Clima Tropical , Brasil , Ecosistema , Biodiversidad
7.
Appl Opt ; 57(25): 7203-7210, 2018 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-30182980

RESUMEN

We report on a fully bidirectional 680 km fiber link connecting two cities for which the equipment, the setup, and the characterization are managed for the first time by an industrial consortium. The link uses an active telecommunication fiber network with parallel data traffic and is equipped with three repeater laser stations and four remote double bidirectional erbium-doped fiber amplifiers. We report a short-term stability at 1 s integration time of 5.4×10-16 in 0.5 Hz bandwidth and a long-term stability of 1.7×10-20 at 65,000 s of integration time. The accuracy of the frequency transfer is evaluated as 3×10-20. No shift is observed within the statistical uncertainty. We show a continuous operation over five days with an uptime of 99.93%. This performance is comparable with the state-of-the-art coherent links established by National Metrology Institutes in Europe. It is a first step in the construction of an optical fiber network for metrology in France, which will give access to an ultrahigh performance frequency standard to a wide community of scientific users.

8.
Phys Rev Lett ; 120(8): 083401, 2018 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-29543028

RESUMEN

We report spectroscopic observation of Rydberg polarons in an atomic Bose gas. Polarons are created by excitation of Rydberg atoms as impurities in a strontium Bose-Einstein condensate. They are distinguished from previously studied polarons by macroscopic occupation of bound molecular states that arise from scattering of the weakly bound Rydberg electron from ground-state atoms. The absence of a p-wave resonance in the low-energy electron-atom scattering in Sr introduces a universal behavior in the Rydberg spectral line shape and in scaling of the spectral width (narrowing) with the Rydberg principal quantum number, n. Spectral features are described with a functional determinant approach (FDA) that solves an extended Fröhlich Hamiltonian for a mobile impurity in a Bose gas. Excited states of polyatomic Rydberg molecules (trimers, tetrameters, and pentamers) are experimentally resolved and accurately reproduced with a FDA.

9.
Braz J Biol ; 78(3): 449-456, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29185609

RESUMEN

Edaphic macrofauna must be better studied if we want to take advantage of their full potential for the restoration of tropical ecosystems. We investigated changes in edaphic macrofauna density and diversity along a secondary succession chronosequence in the Atlantic Forest. Our results show some clear patterns of change in soil macrofauna along the chronosequence. Density did not increase along secondary succession, but was correlated with canopy cover. Diversity was characterized by high dominance of social insects and evenness among other groups. We conclude soil macrofauna has a high capacity to recolonize young forests and that its recovery is considerably fast compared to other ecosystem transformations.


Asunto(s)
Adaptación Fisiológica , Conservación de los Recursos Naturales , Restauración y Remediación Ambiental , Bosques , Microbiología del Suelo/normas , Árboles/crecimiento & desarrollo , Clima Tropical , Animales , Biodiversidad , Brasil , Ecosistema , Suelo/química
10.
Vet Parasitol Reg Stud Reports ; 14: 25-31, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-31014733

RESUMEN

Anthelmintic resistance among cyathostomin parasites is a wide-spread problem. The parasite control guidelines written by the American Association of Equine Practitioners (AAEP) encourages the preservation of anthelmintic efficacy by reducing treatment frequency, using targeted deworming, and implementing environmental management practices. While there is knowledge regarding parasite management practices of affluent horse farms in the United States, surveys rarely explore the rural and underserved regions. The purpose of this study was to observe the management practices of horse farms in rural regions Kentucky, including working Amish farms, and determine factors associated with strongyle prevalence. A total of 160 horses among 38 owners from 28 different farms were enrolled in this study. A questionnaire survey regarding equine information, farm management, and deworming history was performed with each owner. Fecal samples were collected to determine fecal egg counts, perform coprocultures for subsequent strongyle larvae identification, and Strongylus vulgaris specific PCR. Serum samples were collected for the S. vulgaris antibody specific ELISA. The mean number of deworming treatments given in the last year was 2.1 with a 95% confidence interval of 1.9-2.3 with ivermectin being the most common active used. Statistical analysis showed horses treated within the last three months with a macrocylic lactone (ML) drug had significantly lower egg counts than horses treated with a ML 7-9 months ago (p = .0005). Despite the AAEP recommendations to reduce the overall number of treatments by using a surveillance-based approach and to no longer rotate treatments, only 17 horses reportedly had a fecal sample submitted for a fecal egg count and 65 horses were dewormed in a rotational manner. Horses whose owners utilized an informative deworming source (i.e., veterinarian, internet, magazine, local feed store) also had significantly lower counts (p = .0026). All coprocultures were negative for S. vulgaris while five horses were PCR positive. Interestingly, 95 horses tested ELISA positive for S. vulgaris. The strongyle egg counts of the working Amish horses were not significantly different from the other horses in this study and deworming practices including the use of efficacious drugs and low treatment frequencies were in accordance with the AAEP guidelines. This study was the first to summarize deworming management practices of rural regions in Kentucky, including a working Amish community. Overall, horse owners employed deworming practices recommended by the AAEP, however rotational deworming is still commonly implemented and fecal egg counts are rarely used.


Asunto(s)
Antihelmínticos/uso terapéutico , Granjas , Enfermedades de los Caballos/prevención & control , Infecciones Equinas por Strongyloidea/epidemiología , Infecciones Equinas por Strongyloidea/prevención & control , Crianza de Animales Domésticos , Animales , Heces/parasitología , Femenino , Enfermedades de los Caballos/tratamiento farmacológico , Enfermedades de los Caballos/epidemiología , Caballos/parasitología , Ivermectina/uso terapéutico , Kentucky/epidemiología , Masculino , Recuento de Huevos de Parásitos/veterinaria , Prevalencia , Población Rural , Strongylus/genética , Strongylus/aislamiento & purificación , Encuestas y Cuestionarios
11.
Artículo en Inglés | LILACS-Express | LILACS, VETINDEX | ID: biblio-1467112

RESUMEN

Abstract Edaphic macrofauna must be better studied if we want to take advantage of their full potential for the restoration of tropical ecosystems. We investigated changes in edaphic macrofauna density and diversity along a secondary succession chronosequence in the Atlantic Forest. Our results show some clear patterns of change in soil macrofauna along the chronosequence. Density did not increase along secondary succession, but was correlated with canopy cover. Diversity was characterized by high dominance of social insects and evenness among other groups. We conclude soil macrofauna has a high capacity to recolonize young forests and that its recovery is considerably fast compared to other ecosystem transformations.


Resumo A macrofauna edáfica deve ser mais bem estudada se quisermos aproveitar todo o seu potencial para a restauração de ecossistemas tropicais. Nós investigamos as mudanças de densidade e diversidade da macrofauna edáfica em uma cronossequência durante a sucessão secundária na Mata Atlântica. Nossos resultados mostram padrões claros de mudança. A densidade não aumentou ao longo da sucessão secundária, mas foi correlacionada com a cobertura de dossel. A diversidade foi caracterizada pela alta dominância de insetos sociais e equidade entre os demais grupos. Nós concluímos que a macrofauna edáfica tem alta capacidade de recolonizar florestas jovens e que sua recuperação é relativamente rápida se comparada a outras transformações ecossistêmicas.

12.
Artículo en Inglés | LILACS-Express | LILACS, VETINDEX | ID: biblio-1467219

RESUMEN

Abstract The hygienic and sanitary control in Food and Nutrition Units (FNU) is considered a standard procedure to produce adequate meals and reduce the risk of foodborne diseases and hospital infections. This study aimed to evaluate the isolation and identification of bacteria from equipment and food contact surfaces in a hospital FNU as well as to evaluate the sanitary condition. Likewise, it was analyzed the adhesion of the microorganisms on polyethylene cutting boards. The presence of aerobic mesophilic microorganisms, yeasts, molds, coagulase-positive staphylococci, coliform and fecal coliform, and Escherichia coli were analyzed on eating tables, countertop surfaces and cutting boards used for meat or vegetable handling, and equipment such as microwaves and refrigerators. The molecular identification it was done by 16S rRNA gene sequencing. The adhesion of the microorganisms (biofilm formation) on meat and vegetable cutting boards was also evaluated by scanning electron microscopy. The results showed high numbers of all microorganisms, except for E. coli , which was not observed in the samples. The molecular analysis identified species of the Enterobacteriaceae family and species of the Pseudomonadaceae family. Scanning electron microscopy analyses revealed bacterial adhesion on the cutting board surfaces. The results obtained in this study indicated that the hygienic conditions of surfaces like plastic cutting boards and equipment in this hospital FNU were inadequate. The achievement and application of standard operating procedures could positively help in the standardization of sanitary control, reducing the microbial contamination and providing a safe food to hospitalized patients.


Resumo O controle higiênico e sanitário nas Unidades de Alimentação e Nutrição (UAN) é considerado um procedimento padrão para produzir refeições adequadas e reduzir o risco de doenças transmitidas pelos alimentos e infecções hospitalares. Este estudo teve como objetivo isolar e identificar bactérias de equipamentos e superfícies de contato com alimentos em uma UAN hospitalar, bem como avaliar a condição sanitária. Do mesmo modo, analisou-se a adesão dos micro-organismos em tábuas de corte de polietileno. A presença de micro-organismos aeróbios mesófilos, leveduras, fungos, Sthapylococcus coagulase-positivos, coliformes, coliformes fecais e Escherichia coli foi analisadas na superfície de mesas do refeitório, superfícies de bancada e tábuas de corte usadas para manuseio de carne ou vegetais e, em equipamentos como micro-ondas e refrigeradores. A identificação molecular foi feita pelo sequenciamento do gene 16S rRNA. A adesão dos micro-organismos (formação de biofilmes) em tábuas de corte de carne e de vegetais também foi avaliada por microscopia eletrônica de varredura. Os resultados mostraram elevada contagem para todos os micro-organismos analisados, exceto para E. coli, a qual não foi observada nas amostras. A análise molecular identificou espécies da família Enterobacteriaceae e Pseudomonadaceae. A análise de microscopia eletrônica de varredura revelaram adesão bacteriana nas superfícies das placsa de corte. Os resultados obtidos neste estudo indicaram que as condições higiênicas das superfícies e de equipamentos nesta UAN hospitalar estavam inadequadas. A aplicação de procedimentos operacionais padrão poderia auxiliar positivamente na padronização do controle higiênico-sanitário, reduzindo a contaminação microbiana e fornecendo um alimento seguro para pacientes hospitalizados.

14.
Braz J Biol ; 75(4): 868-77, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26675903

RESUMEN

Indigenous plants have been grown naturally and vigorously in copper contaminated soils. Thus, the aim of this study was to evaluate the phytoremediation ability of two indigenous plants naturally grown in two vineyard soils copper contaminated, and in a copper mining waste. However, it was evaluated the macro and micronutrient uptake and the potential of phytoremediation. So, a greenhouse study was carried out with Bidens pilosa and Plantago lanceolata in samples of vineyard soils (Inceptisol and Mollisol) copper contaminated, and in a copper mining waste. Plant growth, macro and micronutrient up take, tolerance index (TI), translocation factor (TF), metal extraction ratio (MER), bioaccumulation factor (BCF), plant effective number of the shoots (PENs), and plant effective number of the total plant (PENt) were analyzed. Both plants grown in vineyard soils showed high phytomass production and TI. P. lanceolata plants cultivated in the Inceptisol showed the highest copper concentrations in the shoots (142 mg kg-1), roots (964 mg kg-1) and entire plants (1,106 mg kg-1). High levels of copper were phytoaccumulated from the Inceptisol by B. pilosa and P. lanceolata with 3,500 and 2,200 g ha-1 respectively. Both B. pilosa and P. lanceolata plants showed characteristics of high copper hyperaccumulator. Results showed that both species play an important role in the natural copper phytoaccumulation in both vineyard soils contaminated with copper, being important to its phytoremediation.


Asunto(s)
Bidens/metabolismo , Cobre/metabolismo , Restauración y Remediación Ambiental , Plantago/metabolismo , Contaminantes del Suelo/metabolismo , Bidens/efectos de los fármacos , Bidens/crecimiento & desarrollo , Biodegradación Ambiental , Brasil , Plantago/efectos de los fármacos , Plantago/crecimiento & desarrollo
15.
Braz J Biol ; 75(4): 923-31, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26675908

RESUMEN

Lactic acid bacteria (LAB) have an important role in a great variety of fermented foods. In addition to their contribution to sensory characteristics, they enhance food preservation and can be used as probiotics. In this study, the antimicrobial and antioxidant activities of culture supernatants and cell free extracts of 16 LAB isolated from meat and dairy products were investigated. The bacterial were identified by 16S rRNA sequencing. GenBank BLAST analysis revealed that all the isolates belong to Enterococcus faecium species. Antimicrobial activity against the indicator microorganism (Listeria monocytogenes) was observed at 11 culture supernatants and 4 cell free extracts. The sensibility of culture supernatant was evaluated by proteinase K and trypsin and it was observed that activity of antimicrobial substance was completely lost after the treatment. All of the isolates showed antioxidant activity as determined by the Thiobarbituric Acid Reactive Substances (TBARS) method with both types of extracts. When the antioxidant capacity was investigated using ABTS•+ method (2,2 azino-bis (3-ethylbenzothiazoline-6-sulfonic acid)) and DPPH method (2,2-diphenyl-1-picrylhydrazyl) it was observed that only culture supernatants showed antioxidant capacity. These bacteria could particularly help to reduce or inhibit pathogenic microorganisms as well as oxidative spoilage in foods and feed.


Asunto(s)
Antiinfecciosos/farmacología , Antioxidantes/análisis , Productos Lácteos/microbiología , Enterococcus/química , Listeria monocytogenes/efectos de los fármacos , Carne/microbiología , Filogenia , ARN Ribosómico 16S , Análisis de Secuencia de ADN , Sustancias Reactivas al Ácido Tiobarbitúrico/química
17.
Braz. j. biol ; 75(4): 923-931, Nov. 2015. tab, graf
Artículo en Inglés | LILACS | ID: lil-768199

RESUMEN

Abstract Lactic acid bacteria (LAB) have an important role in a great variety of fermented foods. In addition to their contribution to sensory characteristics, they enhance food preservation and can be used as probiotics. In this study, the antimicrobial and antioxidant activities of culture supernatants and cell free extracts of 16 LAB isolated from meat and dairy products were investigated. The bacterial were identified by 16S rRNA sequencing. GenBank BLAST analysis revealed that all the isolates belong to Enterococcus faecium species. Antimicrobial activity against the indicator microorganism (Listeria monocytogenes) was observed at 11 culture supernatants and 4 cell free extracts. The sensibility of culture supernatant was evaluated by proteinase K and trypsin and it was observed that activity of antimicrobial substance was completely lost after the treatment. All of the isolates showed antioxidant activity as determined by the Thiobarbituric Acid Reactive Substances (TBARS) method with both types of extracts. When the antioxidant capacity was investigated using ABTS•+ method (2,2 azino-bis (3-ethylbenzothiazoline-6-sulfonic acid)) and DPPH method (2,2-diphenyl-1-picrylhydrazyl) it was observed that only culture supernatants showed antioxidant capacity. These bacteria could particularly help to reduce or inhibit pathogenic microorganisms as well as oxidative spoilage in foods and feed.


Resumo As bactérias ácido láticas (BAL) têm um papel importante em uma grande variedade de alimentos fermentados. Em adição à sua contribuição para as características sensoriais, estes microorganismos melhoram a conservação de alimentos e podem ser utilizados como probióticos. Neste estudo, as atividades antimicrobiana e antioxidante do sobrenadante e dos extratos livres de células de 16 isolados de LAB de carne e produtos lácteos foram investigadas. Os isolados foram identificados pelo sequenciamento da região 16S do rRNA. Após a comparação das sequências obtidas com aquelas disponíveis na base de dados GenBank, observou-e que todos os isolados foram pertencentes à espécie Enterococcus faecium. A atividade antimicrobiana contra o microrganismo indicador (Listeria monocytogenes) foi observada no sobrenadante das culturas em 11 isolados, e nos extratos livres de células por 4 isolados. A sensibilidade da cultura sobrenadante foi avaliada pela proteinase K e tripsina e observou-se que a atividade da substância antimicrobiana foi completamente perdida após o tratamento com as enzimas proteolíticas. Todos os isolados apresentaram atividade antioxidante, como determinado pelo método do ácido tiobarbitúrico de substâncias reativas (TBARS) com ambos os tipos de extratos. Quando a capacidade antioxidante foi investigada usando o método do ABTS (2,2 azino-bis (3-ethylbenzothiazoline-6-sulfonic acid)) e o método de DPPH (2,2-diphenyl-1-picrylhydrazyl) observou-se que apenas os sobrenadantes das culturas demonstraram capacidade antioxidante. Estas bactérias poderiam particularmente ajudar a reduzir ou inibir microorganismos patogênicos, bem como a deterioração oxidativa em alimentos e rações.


Asunto(s)
Antiinfecciosos/farmacología , Antioxidantes/análisis , Productos Lácteos/microbiología , Enterococcus/química , Listeria monocytogenes/efectos de los fármacos , Carne/microbiología , Filogenia , Análisis de Secuencia de ADN , Sustancias Reactivas al Ácido Tiobarbitúrico/química
18.
Braz. j. biol ; 75(4): 868-877, Nov. 2015. tab, graf
Artículo en Inglés | LILACS | ID: lil-768201

RESUMEN

Abstract Indigenous plants have been grown naturally and vigorously in copper contaminated soils. Thus, the aim of this study was to evaluate the phytoremediation ability of two indigenous plants naturally grown in two vineyard soils copper contaminated, and in a copper mining waste. However, it was evaluated the macro and micronutrient uptake and the potential of phytoremediation. So, a greenhouse study was carried out with Bidens pilosa and Plantago lanceolata in samples of vineyard soils (Inceptisol and Mollisol) copper contaminated, and in a copper mining waste. Plant growth, macro and micronutrient up take, tolerance index (TI), translocation factor (TF), metal extraction ratio (MER), bioaccumulation factor (BCF), plant effective number of the shoots (PENs), and plant effective number of the total plant (PENt) were analyzed. Both plants grown in vineyard soils showed high phytomass production and TI. P. lanceolata plants cultivated in the Inceptisol showed the highest copper concentrations in the shoots (142 mg kg–1), roots (964 mg kg–1) and entire plants (1,106 mg kg–1). High levels of copper were phytoaccumulated from the Inceptisol by B. pilosa and P. lanceolata with 3,500 and 2,200 g ha–1 respectively. Both B. pilosa and P. lanceolata plants showed characteristics of high copper hyperaccumulator. Results showed that both species play an important role in the natural copper phytoaccumulation in both vineyard soils contaminated with copper, being important to its phytoremediation.


Resumo Plantas nativas crescem naturalmente e vigorosamente em solos contaminados com cobre. Assim, o objetivo deste estudo foi avaliar a capacidade de fitorremediação de duas plantas nativas, naturalmente encontradas em dois solos de vitivinicultura contaminados com cobre, e em rejeito de mineração de cobre. Foram avaliados os teores de macro e micronutrientes nos tecidos das plantas, e o potencial de fitorremediação. Assim, um estudo em casa de vegetação foi realizado com plantas de Bidens pilosa e Plantago lanceolata, com amostras de dois solos de vitivinicultura (Neossolos e Cambissolos) contaminados com cobre, e com rejeito de mineração de cobre. O crescimento das plantas, teores de macro e micronutrientes nos tecidos, índice de tolerância (TI), fator de translocação (TF), taxa de extração do metal (MER), fator de bioacumulação (BCF), número efetivo dos plantas da parte aérea (PENs) e número efetivo de plantas inteiras (PENt) foram analisados. Ambas as espécies cultivadas em solos vitivinicultura mostraram elevada produção de fitomassa e os TI. P. lanceolata cultivadas no Neossolo mostraram as concentrações de cobre mais elevados na parte aérea (142 mg kg–1), nas raízes (964 mg kg–1) e nas plantas inteiras (1.106 mg kg–1). Altos níveis de cobre foram fitoacumulados pelas plantas B. pilosa e P. lanceolata com 3.500 e 2.200 g ha–1, respectivamente, quando cultivadas em Neossolo. Ambas as espécies apresentaram características hiperacumuladoras de cobre. Os resultados mostraram que estas espécies desempenham um papel importante na fitoacumulação de cobre naturalmente em ambos os solos de vitivinicultura contaminados com cobre, sendo importantes para a fitorremediação.


Asunto(s)
Bidens/metabolismo , Cobre/metabolismo , Restauración y Remediación Ambiental , Plantago/metabolismo , Contaminantes del Suelo/metabolismo , Biodegradación Ambiental , Brasil , Bidens/efectos de los fármacos , Bidens/crecimiento & desarrollo , Plantago/efectos de los fármacos , Plantago/crecimiento & desarrollo
19.
Int J Immunopathol Pharmacol ; 26(4): 889-96, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24355224

RESUMEN

Human leukocyte antigen (HLA)–E is a non-classical molecule of the histocompatibility complex that functions as one of the main ligands of the Natural Killer (NK) cell inhibitory receptor CD94/NKG2A and inhibits its potent cytotoxic activity. Due to the important role of NK cells in combating neoplasm, we hypothesized that the differential expression of HLA-E could favor the progression of heterogeneous thyroid tumors.Using an immunohistochemistry technique in 143 biopsies of thyroid tumors, including benign and malignant neoplasms and goiters, we evaluated the expression of HLA-E among various tumor types and its association with the clinicopathological factors of diseases. We verified high HLA-E expression in all types of neoplastic tumors, although no significant differences between the groups were found. Low expression was observed in 95 percent of the goiter samples, showing significant differences between neoplastic and non-neoplastic lesions. Furthermore, a significant result was found with regard to the tumor size, with high HLA-E expression being related to smaller tumors. Therefore, our data suggest that an increase in HLA-E may be associated with the establishment of thyroid neoplasms, with either benign or malignant features.


Asunto(s)
Antígenos de Histocompatibilidad Clase I/análisis , Glándula Tiroides/inmunología , Neoplasias de la Tiroides/inmunología , Adulto , Anciano , Femenino , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Antígenos HLA-E
20.
Acta pediatr. esp ; 71(11): e347-e352, dic. 2013. tab, graf
Artículo en Español | IBECS | ID: ibc-118830

RESUMEN

Objetivo: Describir el grado de control metabólico en jóvenes con diabetes mellitus tipo 1 (DM1) y analizar los factores que pueden influir en él. Material y métodos: Se realizó un estudio descriptivo y observacional, con una recogida de datos retrospectiva, en el que se incluyó a pacientes con DM1 que acudieron a los campamentos de verano organizados por la Fundación Sociosanitaria de Castilla-La Mancha durante los años 2009 y 2010. Se determinó la hemoglobina glucosilada (HbA1c) en sangre capilar (método DCA 2000+). Se llevó a cabo un análisis estadístico mediante el programa SPSS. Resultados: Se incluyeron en el estudio 85 pacientes, con una media edad de 13,5 años. El 100% de los pacientes recibía una pauta de insulinoterapia intensiva: infusión subcutánea continua de insulina (8,2%), insulina detemir (10,6%), insulina glargina (70,6%) e insulina NPH (neutral protamine Hagedorn) (10,6%). Se realizó una media de 5,4 autoanálisis diarios (rango: 3-12). El valor medio de HbA1c era del 7,6% (rango: 5,7-13,7), presentando el 33% una HbA1c ≤7%, el 32% una HbA1c >7% y ≤8%, y un 35% una HbA1c >8%. No se encontraron diferencias significativas en función de la consulta de procedencia ni de la pauta de insulina empleada, y se observaron valores de HbA1c significativamente menores en los pacientes con menos de 2 años de evolución.Conclusiones: El factor que más influye en la HbA1c de los pacientes analizados es el tiempo de evolución de la enfermedad, sin diferencias significativas en función de la pauta de insulinoterapia (AU)


Objective: To describe the degree of metabolic control in youth with type 1 diabetes mellitus (DM1) and analyze the factors that influence in this control. Material and methods: We performed a descriptive, observational and retrospective study which includes patients with DM1 attending summer camps organized by the Fundación Sociosanitaria de Castilla-La Mancha during the years 2009 and 2010. Glycosylated hemoglobin (HbA1c) is measured in capillary blood (method DCA 2000+). Statistical analysis was performed using SPSS. Results: We collected 85 patients with mean age of 13.5 years. 100% of patients receiving intensive insulin regimen: continuous subcutaneous insulin infusion (8.2%), detemir (10.6%), glargine (70.6%) and NPH (10.6%). The mean HbA1c is 7.6% (5.7 to 13.7%), with 33% HbA1c ≤7%, 32% HbA1c >7% and ≤8%, and 35% HbA1c ≥8%. No significant differences were found depending on the consultation of origin or the pattern of insulin used, with values of HbA1c significantly lower in patients with less than 2 years of evolution. Conclusions: The factor that most influences the HbA1c of the patients analyzed is the time to disease progression, with no differences according to the pattern of insulin (AU)


Asunto(s)
Humanos , Masculino , Femenino , Niño , Diabetes Mellitus Tipo 1/fisiopatología , Hemoglobina Glucada/análisis , Hiperglucemia/prevención & control , Sistemas de Infusión de Insulina , Insulina/uso terapéutico , Índice Glucémico , Acampada
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