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1.
Bioresour Technol ; 387: 129643, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37562492

RESUMEN

This study addresses the problem of replacing nitrate and ammonium with urea as a greener nitrogen source in the mass cultivation of the microalga Amphidinium carterae for the development of amphidinol-based phytosanitary products. To solve this problem, a nuclear magnetic resonance assisted investigation evaluated the effect of nitrogen sources on growth and metabolic profiles in photobioreactors. Urea-fed cultures exhibited growth kinetics comparable to nitrate-fed cultures (µmax = 0.30 day-1, Pbmax = 43 mgL-1day-1). Urea-fed cultures had protein, lipid, and carbohydrate contents of 39.5%, 14.5%, and 42.4%, respectively, while nitrate-fed cultures had 27.9 %, 17.5% and 48.1%, respectively. Metabolomics revealed nitrogen source-dependent metabotypes and a correlation between amphidinols and polyunsaturated fatty acids. The amphidinol-to-nitrogen yield coefficient in urea-fed cultures (135 mg/g) was approximately 2.5 times higher than in nitrate-fed cultures. The potent antiphytopathogenic activity exhibited by extracts from urea-fed cultures underscores the potential of urea as a sustainable nitrogen source in microalgae-based biorefineries.


Asunto(s)
Dinoflagelados , Microalgas , Plaguicidas , Urea , Plaguicidas/metabolismo , Biomasa , Fotobiorreactores , Nitrógeno/metabolismo , Nitratos/metabolismo , Dinoflagelados/metabolismo , Microalgas/metabolismo
2.
Bioresour Technol ; 342: 125922, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34547712

RESUMEN

An amphidinol-prioritized fractioning approach was for the first time developed to isolate multiple specialty metabolites such as amphidinols, carotenoids and fatty acids using the biomass of the marine microalgae Amphidinium carterae. The biomass was produced in a raceway photobioreactor and the exhausted culture media were reused, thus fulfilling sustainability criteria employing a circular economy concept. The integrated bioactive compounds-targeted approach presented here consisted of four steps with which recovery percentages of carotenoids, fatty acids and amphidinols of 97%, 82% and 99 %, respectively, were achieved. The proposed process was proved to be a better extraction system for this microalga than another based on a sequential gradient partition with water and four water-immiscible organic solvents (hexane, carbon tetrachloride, dichloromethane and n-butanol). The proposed process could be scaled-up as a commercial solid-phase extraction technology well-established for industrial bioprocesses.


Asunto(s)
Dinoflagelados , Microalgas , Biomasa , Carotenoides , Fotobiorreactores
3.
Bioresour Technol ; 313: 123518, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32512427

RESUMEN

The extraction of three families of compounds (carotenoids, fatty acids and amphidinols) from the biomass of two strains of Amphidinium carterae (ACRN03 and Dn241EHU) was improved by tuning cell disruption and solvent extraction operations. The extraction of carotenoids was evaluated using alkaline saponification (0%-60% KOH d.w.) at different temperatures (25-80 °C). High levels of carotenoids were obtained at 60 °C using freeze-dried biomass, not subjected to cell disruption methods. The ACRN03 strain required 20% KOH whereas the Dn241EHU strain did not require saponification since carotenoid degradation was observed. The extraction efficiencies were determined with a wide range of pure solvents and mixtures thereof. Two empirical non-linear equations were used to correlate extraction percentages for each family of compounds with the Hildebrand solubility parameter (δT) and the polarity index of the solvents (PI). Thresholds of δT and PI of around 20 MPa1/2 and 6, respectively, were determined for the extraction of amphidinols, consistent with antiproliferative activity measurements.


Asunto(s)
Dinoflagelados , Microalgas , Biomasa , Carotenoides , Ácidos Grasos , Solventes
4.
Arq. bras. med. vet. zootec. (Online) ; 72(1): 65-70, Jan.-Feb. 2020. ilus
Artículo en Portugués | LILACS, VETINDEX | ID: biblio-1088922

RESUMEN

O presente trabalho relata o caso de aspergilose sistêmica em um cavalo da raça Quarto de Milha. O animal apresentava quadro de emagrecimento progressivo e alopecia. Os parâmetros avaliados durante o exame clínico encontravam-se de acordo com os valores normais para a espécie. No hemograma verificou-se leucocitose por neutrofilia, sem desvio à esquerda, proteínas plasmáticas totais elevadas e aumento do fibrinogênio, indicando um processo inflamatório acompanhado de desidratação. Os exames bioquímicos séricos demonstraram aumento no valor da ureia. Apesar dos exames realizados e da terapia instituída com antibióticos de amplo espectro e suporte nutricional, após 51 dias de internamento o quadro clínico evoluiu para caquexia e decúbito permanente do paciente, o qual foi submetido à eutanásia seguida de necropsia. Com base nos achados nos exames necroscópico e histopatológico, diagnosticou-se infecção sistêmica por Aspergillus sp., acometendo pulmões, fígado, rins, peritônio parietal e encéfalo. Dentre os fatores predisponentes à relatada infecção fúngica sistêmica, destaca-se o status imunológico debilitado do paciente, possivelmente proporcionado por tratamentos prolongados com antibióticos e anti-inflamatórios esteroidais. O presente trabalho relata o primeiro caso descrito de arpergilose sistêmica no Brasil. O diagnóstico definitivo só foi possível após necropsia e histopatologia, visto que os sinais clínicos inespecíficos não foram determinantes para o diagnóstico em vida.(AU)


This paper reports the case of systemic aspergillosis on a Quarter Horse. The animal had progressive weight loss and alopecia. The parameters evaluated during the clinical examination were in agreement with the normal values for the species. The hemogram showed neutrophilic leukocytosis, without left-sided, elevated total plasma proteins and an increase in fibrinogen, indicating an inflammatory process accompanied by dehydration. Serum biochemical tests showed an increase in the value of urea. Despite the performed tests and established therapy with broad spectrum antibiotics and nutritional support, after 51 days of hospitalization the clinical condition evolved into cachexia and permanent decubitus of the patient which underwent to euthanasia and necropsy. From the findings of necropsy and histopathology, systemic infection was diagnosed by Aspergillus sp., affecting the lungs, liver, kidneys, parietal peritoneum and encephalon. Among the factors predisposing to the reported systemic fungal infection, the patient's weakened immune status is highlighted, possibly due to prolonged antibiotic and steroidal anti-inflammatory treatments. This paper reports the first case described of systemic aspergillosis in Brazil. Definitive diagnosis was only possible after necropsy and histopathology, since nonspecific clinical signs were not determinant for the diagnosis in life.(AU)


Asunto(s)
Animales , Aspergilosis/veterinaria , Terapia de Inmunosupresión/veterinaria , Caballos , Autopsia/veterinaria
5.
RSC Adv ; 10(48): 28484-28491, 2020 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-35520094

RESUMEN

Environmental conditions have a profound effect on the photophysical behavior of highly conjugated compounds, which can be exploited in a large variety of applications. In this context, we use a combination of experimental and computational methods to investigate thermal and solvatochromic effects on the fluorescence properties of a dansyl derivative bearing a thienyl substituent, namely 2-(3-thienyl)ethyl dansylglycinate (TEDG). In particular, we analyze how the solvent polarity and temperature affect the ground and excited state energies of TEDG by using time-resolved and steady-state fluorescence techniques. We determine the changes in dipole moment of the TEDG molecule upon photoexcitation, as well as the solvent polarity effects on the excited state lifetime. Besides, we provide theoretical modeling of the HOMO-LUMO orbitals and the vertical absorption and emission energies using time-dependent density functional theory (TDDFT) as well as the polarizable continuum model (PCM) to include the solvent contribution to the absorption and emission energies. Our results show that the emission mechanism of TEDG involves locally excited states derived from hybrid molecular orbitals, accompanied by a moderate variation of the molecular dipole moment upon light excitation. Our findings demonstrate that TEDG exhibits desirable fluorescence properties that make it a promising candidate for use as a photoactive material in electrochromic, optical thermometry, and thermography applications.

6.
Lett Appl Microbiol ; 68(4): 313-320, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30790318

RESUMEN

The aim of this study was the development of a novel and effective antibacterial formulation combining selected phytochemical compounds (quercetin, cuminaldehyde, indole-3-carbinol and vanillic acid) with ethylenediaminetetraacetic acid (EDTA), an aminopolycarboxylic acid. The antibacterial activity of the combinations was evaluated against Escherichia coli and Staphylococcus epidermidis in planktonic and sessile states as single and dual species. The compounds when applied individually demonstrated modest antibacterial activity. Nevertheless, synergy was observed when EDTA was combined with the selected phytochemicals, particularly with cuminaldehyde and indole-3-carbinol. These combinations were evaluated against single- and dual-species biofilms. An inactivation of 100% was obtained for almost all the biofilms, with E. coli biofilms showing the highest resistance. This study allowed the discovery of novel formulations of phytochemical compounds with antibacterial activity against E. coli and S. epidermidis single- and dual-species biofilms at concentrations close to the minimum bactericidal concentration. SIGNIFICANCE AND IMPACT OF THE STUDY: The synergistic combinations of EDTA and cuminaldehyde or indole-3-carbinol were effective against single- and dual-species E. coli and S. epidermidis planktonic cells and biofilms. The overall results highlight the role of phytochemical products as a green and sustainable source of antimicrobial potentiators to control bacteria in both planktonic and sessile states.


Asunto(s)
Biopelículas/crecimiento & desarrollo , Ácido Edético/farmacología , Escherichia coli/crecimiento & desarrollo , Fitoquímicos/farmacología , Staphylococcus epidermidis/crecimiento & desarrollo , Antibacterianos/farmacología , Benzaldehídos/farmacología , Cimenos , Indoles/farmacología , Pruebas de Sensibilidad Microbiana , Plancton , Quercetina/farmacología , Ácido Vanílico/farmacología
7.
Parkinsonism Relat Disord ; 18(2): 185-90, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22001711

RESUMEN

UNLABELLED: Machado-Joseph disease/spinocerebellar ataxia type 3 (MJD/SCA3) may rarely presents a parkinsonian phenotype. Considering that mutations in the glucocerebrosidase (GBA) gene have been associated with Parkinson disease, we investigated whether these would be more prevalent in MJD/SCA3 patients with parkinsonian manifestations than in those without them. METHODS: MJD/SCA3 patients with parkinsonian features were identified and compared to relatives and to a MJD/SCA3 control group with no such features. The GBA gene was sequenced and, in a subset of patients and in normal volunteers, GBA enzyme activity was measured. RESULTS: We have identified nine index MJD/SCA3 patients with parkinsonian manifestations. Overall, GBA sequence variations were found in 3/9 MJD/SCA3 index cases with parkinsonian manifestations (33%) and in 0/40 MJD/SCA3 controls without parkinsonism (p=0.03, Fisher exact test). The GBA sequence variations found were p.K(-27)R, p.E326K, and p.T369M. The latter two sequence variations were also found in two symptomatic relatives with no parkinsonian manifestations. A MJD/SCA3 relative belonging to the first positive pedigree and carrier of the p.K(-27)R mutation also presented parkinsonian manifestations. GBA activity in MJD/SCA3 patients was similar to those found in the normal control group. CONCLUSION: Sequence variations at the GBA gene may play a role as a minor, modifying gene of MJD/SCA3 phenotype. This hypothetical role was not related to changes in GBA activity in peripheral leukocytes.


Asunto(s)
Variación Genética , Glucosilceramidasa/genética , Enfermedad de Machado-Joseph/enzimología , Enfermedad de Machado-Joseph/genética , Trastornos Parkinsonianos/enzimología , Trastornos Parkinsonianos/genética , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Linaje
8.
Histol Histopathol ; 16(1): 185-95, 2001 01.
Artículo en Inglés | MEDLINE | ID: mdl-11193194

RESUMEN

The histopathological changes induced in avian kidney by the intramuscular injection of Bothrops insularis (jararaca ilh a) venom and its phospholipase A2 (PLA2)-containing fraction were examined. Acute experiments (3 h and 24 h) with B. insularis crude venom (20 microg and 80 microg) or its PLA2-contaning fraction (10 microg and 40 microg) resulted in significant structural damage to the kidneys of 5-12-day-old chicks. Histopathological analysis indicated that the venom and its fraction acted on the renal tubules and glomeruli. The morphological changes, although widespread, varied in intensity from cell to cell, and from tubule to tubule in venom-injected chicks. The tubular and glomerular changes produced by the venom and its PLA2-containing fraction may be the result of a direct cytotoxic effect potentiated by ischemia-related disturbances in the regional hemodynamics. The venom and its fraction affected more segments along reptilian-type nephrons than along mammalian ones. This divergent sensitivity to the venom and its fraction may reflect the species-specific characteristics of B. insularis snake, an example of geographical isolation influencing its diet which is almost exclusively avian.


Asunto(s)
Bothrops , Pollos/fisiología , Venenos de Crotálidos/toxicidad , Riñón/patología , Fosfolipasas A/toxicidad , Animales , Conducta Animal/efectos de los fármacos , Venenos de Crotálidos/administración & dosificación , Venenos de Crotálidos/enzimología , Inyecciones Intramusculares , Masculino , Adhesión en Parafina , Fosfolipasas A/administración & dosificación , Fosfolipasas A2 , Insuficiencia Respiratoria/inducido químicamente , Insuficiencia Respiratoria/patología , Factores de Tiempo , Uréter/patología
9.
J. pediatr. (Rio J.) ; 57(2): 130-4, 1984.
Artículo en Portugués | LILACS | ID: lil-22071

RESUMEN

Os autores se propoem a relatar o estudo restrospectivo sobre tumor de Wilms, em pacientes admitidos e tratados no Hospital Infantil Albert Sabin, da FUSEC, no periodo de fevereiro de 79 a fevereiro de 83.Neste periodo foram admitidas 16 criancas portadoras dessa patologia, todas submetidas ao tratamento classico preconizado para tumor de Wilms, constando basicamente de cirurgia radical, quimioterapia e radioterapia pos-operatorias. Neste estudo foram aventados e analisados os seguintes parametros: 1 - Correlacao entre a sobrevida e o estadiamento clinico-cirurgico.2Correlacao entre sobrevida e estadiamento histologico.3 - Achados radiologicos (urograficos). 4 - Correlacao entre as condicoes clinicas no momento da internacao e sobrevida. Os autores concluiram que: 1- A sobrevida global nao foi tao satisfatoria como era de se esperar, em funcao dos estadios clinicos avancados e das mas condicoes clinicas iniciais. 2 - O numero relativamente grande de estadios II (de pessimo prognostico) contribuiu para o aumento da mortalidade. 3 - A histologia favoravel demonstrou melhorar o prognostico mesmo em estadios clinicos avancados (sobrevida longa em estadio IV)


Asunto(s)
Lactante , Preescolar , Niño , Humanos , Masculino , Femenino , Tumor de Wilms , Estadificación de Neoplasias
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