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71.
Marta Louano Joana Oliveira Isabel Martins Rui Vaz Isaura Tavares 《International journal of molecular sciences》2022,23(7)
Pain transmission at the spinal cord is modulated by noradrenaline (NA)-mediated actions that arise from supraspinal areas. We studied the locus coeruleus (LC) to evaluate the expression of the cathecolamine-synthetizing enzyme tyrosine hydroxylase (TH) and search for local oxidative stress and possible consequences in descending pain modulation in a model of hydrocephalus, a disease characterized by enlargement of the cerebral ventricular system usually due to the obstruction of cerebrospinal fluid flow. Four weeks after kaolin injection into the cisterna magna, immunodetection of the catecholamine-synthetizing enzymes TH and dopamine-β-hydroxylase (DBH) was performed in the LC and spinal cord. Colocalization of the oxidative stress marker 8-OHdG (8-hydroxyguanosine; 8-OHdG), with TH in the LC was performed. Formalin was injected in the hindpaw both for behavioral nociceptive evaluation and the immunodetection of Fos expression in the spinal cord. Hydrocephalic rats presented with a higher expression of TH at the LC, of TH and DBH at the spinal dorsal horn along with decreased nociceptive behavioral responses in the second (inflammatory) phase of the formalin test, and formalin-evoked Fos expression at the spinal dorsal horn. The expression of 8-OHdG was increased in the LC neurons, with higher co-localization in TH-immunoreactive neurons. Collectively, the results indicate increased noradrenergic expression at the LC during hydrocephalus. The strong oxidative stress damage at the LC neurons may lead to local neuroprotective-mediated increases in NA levels. The increased expression of catecholamine-synthetizing enzymes along with the decreased nociception-induced neuronal activation of dorsal horn neurons and behavioral pain signs may indicate that hydrocephalus is associated with alterations in descending pain modulation. 相似文献
72.
Sónia Soares Joana S. Amaral Maria Beatriz P.P. Oliveira Isabel Mafra 《Comprehensive Reviews in Food Science and Food Safety》2017,16(5):1072-1100
Honey is a highly consumed natural product, not only for its taste and nutritional value, but also for its health benefits. Owing to characteristics that are essentially or exclusively related to the specific region or particular local environment and flora, honey can be classified as a premium product generally perceived as a high‐quality and valued product because of its desirable flavor and taste. Consequently, honey has been a target of adulteration through inappropriate/fraudulent production practices and mislabeling origin. Globally, authentication of honey covers 2 main aspects: the production, with main issues related to sugar syrup addition, filtration, thermal treatment, and water content; and the labeled origin (geographical and/or botanical) and “organic” provenance. This review addresses all those issues, focusing on the approaches to detect the different types of honey adulteration. Due to the complex nature of honey and to the different types of adulteration, its authentication has been challenging and prompted the development of several advanced analytical approaches. Therefore, an updated, critical, and extensive overview on the current and advanced analytical methods targeting markers of adulteration/authenticity, including nontarget fingerprint approaches will be provided. The most recent advances on molecular, chromatographic, and spectroscopic methodologies will be described, emphasizing their pros and cons for the identification of botanical and geographical origins. 相似文献
73.
Joana Barbosa 《Food Reviews International》2017,33(4):335-358
The use of spray-drying for the production of powdered fruit juices has been a common practice in recent years since it is a simple, economic, and advantageous technique. The current knowledge on the different spray-drying parameters, allowing the best conditions to obtain high-quality powders, is presented in this review. The incorporation of probiotic cultures into fruit juices can enhance the functional characteristics of fruit juices. The selection of these probiotics and their benefits to consumers’ health are briefly discussed. As maintaining the viability of probiotics is extremely important in the development of a probiotic functional product, the factors that influence and improve survival, in all pre- and post-spray-drying steps, are also detailed. Finally, a few studies on probiotic fruit juices obtained by spray-drying are cited. Industries should bet on their development and commercialization, since despite being challenging to develop, these are very innovative and attractive products meeting modern consumer demands. 相似文献
74.
Patrícia Costa Sandra Gonçalves Patrícia Valentão Paula B. Andrade Carlos Almeida José M.F. Nogueira Anabela Romano 《Food chemistry》2013
We investigated the metabolic profile and biological activities of the essential oil and polar extracts of Lavandula pedunculata subsp. lusitanica (Chaytor) Franco collected in south Portugal. Gas chromatography–mass spectrometry (GC–MS) analysis revealed that oxygen-containing monoterpenes was the principal group of compounds identified in the essential oil. Camphor (40.6%) and fenchone (38.0%) were found as the major constituents. High-performance liquid chromatography with diode array detection (HPLC–DAD) analysis allowed the identification of hydroxycinnamic acids (3-O-caffeoylquinic, 4-O-caffeoylquinic, 5-O-caffeoylquinic and rosmarinic acids) and flavones (luteolin and apigenin) in the polar extracts, with rosmarinic acid being the main compound in most of them. The bioactive compounds from L. pedunculata polar extracts were the most efficient free-radical scavengers, Fe2+ chelators and inhibitors of malondialdehyde production, while the essential oil was the most active against acetylcholinesterase. Our results reveal that the subspecies of L. pedunculata studied is a potential source of active metabolites with a positive effect on human health. 相似文献
75.
Nathália de Andrade Neves Lílian de Araújo Pantoja Alexandre Soares dos Santos 《European Food Research and Technology》2014,238(1):79-84
This study examined the thermovinification technique using yeasts immobilized on calcium alginate for microvinification of the Cabernet Sauvignon and Pinot Noir grape varieties grown in Diamantina, Minas Gerais, Brazil. The wines obtained by thermovinification were characterized by their chemical and sensory aspects. The varietal wines from Cabernet Sauvignon and Pinot Noir had an alcohol content of 9.3 and 10.9 % (v/v), respectively. The total acidity, volatile acidity and the alcohol/reduced dry extract ratio were consistent with the Brazilian standards established for identity and quality of wines. There was a significant reduction in the levels of anthocyanins, flavonoids and total phenolic compounds after aging in the bottle. The sensory evaluation presented an acceptability exceeding 60 % for both wines. 相似文献
76.
Joana Tavares Dr. Ali Ouaissi Dr. Paul Kong Thoo Lin Prof. Dr. Inês Loureiro Simranjeet Kaur Nilanjan Roy Dr. Anabela Cordeiro‐da‐Silva Prof. Dr. 《ChemMedChem》2010,5(1):140-147
The NAD+‐dependent deacetylases, namely sirtuins, are involved in the regulation of a variety of biological processes such as gene silencing, DNA repair, longevity, metabolism, apoptosis, and development. An enzyme from the parasite Leishmania infantum that belongs to this family, LiSIR2RP1, is a NAD+‐dependent tubulin deacetylase and an ADP‐ribosyltransferase. This enzyme's involvement in L. infantum virulence and survival underscores its potential as a drug target. Our search for selective inhibitors of LiSIR2RP1 has led, for the first time, to the identification of the antiparasitic and anticancer bisnaphthalimidopropyl (BNIP) alkyl di‐ and triamines (IC50 values in the single‐digit micromolar range for the most potent compounds). Structure–activity studies were conducted with 12 BNIP derivatives that differ in the length of the central alkyl chain, which links the two naphthalimidopropyl moieties. The most active and selective compound is the BNIP diaminononane (BNIPDanon), with IC50 values of 5.7 and 97.4 μM against the parasite and human forms (SIRT1) of the enzyme, respectively. Furthermore, this compound is an NAD+‐competitive inhibitor that interacts differently with the parasite and human enzymes, as determined by docking analysis, which might explain its selectivity toward the parasitic enzyme. 相似文献
77.
María J Benito Mar Rodríguez María G Crdoba María J Andrade Juan J Crdoba 《Journal of the science of food and agriculture》2005,85(2):273-280
Proteolytic activity of the fungal protease EPg222 and its effect on the texture of the dry fermented sausage ‘salchichón’, which has a long ripening process, was assayed. Samples with enzyme added showed a significant reduction of myofibrillar protein concentration during the ripening period, compared with a control, and proteolytic activity of the enzyme led to a higher accumulation of non‐protein and ‐amino acid nitrogen. Analysis of volatile compounds in ripened dry fermented sausages revealed that only in EPg222 batches were branched compounds derived from amino acids catabolism detected that are associated with the flavour of dry cured meat products. The texture profile analysis showed reduction in hardness, gumminess and chewiness values in treated compared with control sausages. The effect of this enzyme could be of great interest in stimulating proteolysis, in flavour development and in reducing the hardness of dry fermented sausages produced by a long ripening process. Copyright © 2004 Society of Chemical Industry 相似文献
78.
Linear poly(hydroxyethyl methacrylate) (PHEMA) has been synthesized in highly syndiotactic and highly isotactic configurations. The high syndiotactic PHEMA prepared by u.v. photolysis at ?40° C was found by 13C n.m.r. to have a tactic triad content of 84% syndio, 16% hetero and 0% iso. High isotactic PHEMA was prepared by anionic polymerization of benzoxyethyl methacrylate in toluene followed by selective hydrolysis of the benzoate ester, and was observed by 13C n.m.r. to have a 5% syndio, 15% hetero and 80% isotactic triad content. A linear PHEMA polymer formed by radical polymerization at 60°C in ethanol solvent was found to have a tactic triad content of 58% syndio, 42% hetero and 0% iso. These polymers have been crosslinked with hexamethylene diisocyanate and their water swelling properties determined as functions of temperature and crosslinker concentration. Isotactic PHEMA exhibited greater aqueous swelling below 30° C than the syndiotactic PHEMA samples. The stereochemistry of the polymer chain is shown to be a factor in determining the swelling behaviour of hydrophilic methacrylate gels. 相似文献
79.
M. Valencia E. López S. Andrade Iris M.L. N. Guillén Hurtado V. Rico Pérez A. García García C. Salinas Martínez de Lecea A. Bueno López 《Topics in Catalysis》2013,56(1-8):452-456
The active phase Ce0.5Pr0.5O2 has been loaded on commercial substrates (SiC DPF and cordierite honeycomb monolith) to perform DPF regeneration experiments in the exhaust of a diesel engine. Also, a powder sample has been prepared to carry out soot combustion experiments at laboratory. Experiments performed in the real diesel exhaust demonstrated the catalytic activity of the Ce–Pr mixed oxide for the combustion of soot, lowering the DPF regeneration temperature with regard to a counterpart catalyst-free DPF. The temperature for active regeneration of the Ce0.5Pr0.5O2-containing DPF when the soot content is low is in the range of 500–550 °C. When the Ce0.5Pr0.5O2-containing DPF is saturated with a high amount of soot, pressure drop and soot load at the filter reach equilibrium at around 360 °C under steady state engine operation due to passive regeneration. The uncoated DPF reached this equilibrium at around 440 °C. Comparing results at real exhaust with those at laboratory allow concluding that the Ce0.5Pr0.5O2-catalysed soot combustion in the real exhaust is not based on the NO2-assisted mechanism but is most likely occurring by the active oxygen-based mechanism. 相似文献
80.
Organic coatings based on epoxy and polyurethane matrices containing polyaniline doped with dodecyl benzene sulfonic acid (Pani-DBSA) were prepared and applied over steel plates (SAE 1020). The plates were submitted to salt spray chamber for up to 30 days in order to evaluate the corrosion protection of these coatings. The properties of the coated plates were analyzed as a function of time by electrochemical impedance spectroscopy, open circuit potential, optical microscopy, and Raman spectroscopy. In general, results indicate a decrease in the electrical resistance, increase in capacitance and decrease in open circuit potential. Epoxy based coatings have improved performance when Pani-DBSA is used as pigment, whereas for the polyurethane coatings, Pani-DBSA seems to play an adverse effect. Raman spectroscopy indicates a possible chlorination of the epoxy matrix after 30 days exposure to salt spray chamber. 相似文献