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1.
Proc Natl Acad Sci U S A ; 121(24): e2316419121, 2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38830089

RESUMEN

The extinction of the woolly rhinoceros (Coelodonta antiquitatis) at the onset of the Holocene remains an enigma, with conflicting evidence regarding its cause and spatiotemporal dynamics. This partly reflects challenges in determining demographic responses of late Quaternary megafauna to climatic and anthropogenic causal drivers with available genetic and paleontological techniques. Here, we show that elucidating mechanisms of ancient extinctions can benefit from a detailed understanding of fine-scale metapopulation dynamics, operating over many millennia. Using an abundant fossil record, ancient DNA, and high-resolution simulation models, we untangle the ecological mechanisms and causal drivers that are likely to have been integral in the decline and later extinction of the woolly rhinoceros. Our 52,000-y reconstruction of distribution-wide metapopulation dynamics supports a pathway to extinction that began long before the Holocene, when the combination of cooling temperatures and low but sustained hunting by humans trapped woolly rhinoceroses in suboptimal habitats along the southern edge of their range. Modeling indicates that this ecological trap intensified after the end of the last ice age, preventing colonization of newly formed suitable habitats, weakening stabilizing metapopulation processes, triggering the extinction of the woolly rhinoceros in the early Holocene. Our findings suggest that fragmentation and resultant metapopulation dynamics should be explicitly considered in explanations of late Quaternary megafauna extinctions, sending a clarion call to the fragility of the remaining large-bodied grazers restricted to disjunct fragments of poor-quality habitat due to anthropogenic environmental change.


Asunto(s)
Extinción Biológica , Fósiles , Perisodáctilos , Dinámica Poblacional , Animales , Ecosistema , ADN Antiguo/análisis , Paleontología
2.
Int J Mol Sci ; 25(5)2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38474312

RESUMEN

The role of the epidermal growth factor receptor (EGFR) in tumor progression and survival is often underplayed. Its expression and/or dysregulation is associated with disease advancement and poor patient outcome as well as drug resistance in breast cancer. EGFR is often overexpressed in breast cancer and particularly triple-negative breast cancer (TNBC), which currently lacks molecular targets. We examined the synergistic potential of an EGFR inhibitor (EGFRi) in combination with doxorubicin (Dox) in estrogen-positive (ER+) MCF-7 and MDA-MB-231 TNBC cell lines. The exposure of MDA-MB-231 and MCF-7 to EGFRi produced an IC50s of 6.03 µM and 3.96 µM, respectively. Dox induced MDA-MB-231 (IC50 9.67 µM) and MCF-7 (IC50 1.4 µM) cytotoxicity. Combinations of EGFRi-Dox significantly reduced the IC50 in MCF-7 (0.46 µM) and MBA-MB 231 (0.01 µM). Synergistic drug interactions in both cell lines were confirmed using the Bliss independence model. Pro-apoptotic Caspase-3/7 activation occurred in MCF-7 at 0.1-10 µM of EGFRi and Dox single treatments, whilst 1 µM Dox yielded a more potent effect on MDA-MB-231. EGFRi and Dox individually and in combination downregulated the EGFR gene expression in MCF-7 and MDA-MB-231 (p < 0.001). This study demonstrates EGFRi's potential for eliciting synergistic interactions with Dox, causing enhanced growth inhibition, apoptosis induction, and downregulation of EGFR in both cell lines.


Asunto(s)
Doxorrubicina , Receptores ErbB , Neoplasias de la Mama Triple Negativas , Femenino , Humanos , Apoptosis , Línea Celular Tumoral , Proliferación Celular , Doxorrubicina/farmacología , Receptores ErbB/antagonistas & inhibidores , Células MCF-7 , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Neoplasias de la Mama Triple Negativas/metabolismo , Sinergismo Farmacológico
3.
J Environ Manage ; 359: 121013, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38723495

RESUMEN

Aquaculture pond sediments have a notable influence on the ecosystem balance and farmed animal health. In this study, microalgal-bacterial immobilization (MBI) was designed to improve aquaculture pond sediments via synergistic interactions. The physicochemical characteristics, bacterial communities, and the removal efficiencies of emerging pollutants were systematically investigated. The consortium containing diatom Navicula seminulum and Alcaligenes faecalis was cultivated and established in the free and immobilized forms for evaluating the treatment performance. The results indicated that the immobilized group exhibited superior performance in controlling nutrient pollutants, shaping and optimizing the bacterial community compositions with the enrichment of functional bacteria. Additionally, it showed a stronger positive correlation between the bacterial community shifts and nutrient pollutants removal compared to free cells. Furthermore, the immobilized system maintained the higher removal performance of emerging pollutants (heavy metals, antibiotics, and pathogenic Vibrios) than free group. These findings confirmed that the employment of immobilized N. seminulum and A. faecalis produced more synergistic benefits and exerted more improvements than free cells in ameliorating aquaculture pond sediments, suggesting the potential for engineering application of functional microalgal-bacterial consortium in aquaculture.


Asunto(s)
Acuicultura , Microalgas , Estanques , Microalgas/metabolismo , Sedimentos Geológicos/microbiología , Metales Pesados , Contaminantes Químicos del Agua/metabolismo , Bacterias/metabolismo , Animales
4.
Environ Sci Technol ; 57(46): 18139-18150, 2023 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-37595051

RESUMEN

A growing body of literature suggests that developmental exposure to individual or mixtures of environmental chemicals (ECs) is associated with autism spectrum disorder (ASD). However, investigating the effect of interactions among these ECs can be challenging. We introduced a combination of the classical exposure-mixture Weighted Quantile Sum (WQS) regression and a machine-learning method termed Signed iterative Random Forest (SiRF) to discover synergistic interactions between ECs that are (1) associated with higher odds of ASD diagnosis, (2) mimic toxicological interactions, and (3) are present only in a subset of the sample whose chemical concentrations are higher than certain thresholds. In a case-control Childhood Autism Risks from Genetics and Environment (CHARGE) study, we evaluated multiordered synergistic interactions among 62 ECs measured in the urine samples of 479 children in association with increased odds for ASD diagnosis (yes vs no). WQS-SiRF identified two synergistic two-ordered interactions between (1) trace-element cadmium (Cd) and the organophosphate pesticide metabolite diethyl-phosphate (DEP); and (2) 2,4,6-trichlorophenol (TCP-246) and DEP. Both interactions were suggestively associated with increased odds of ASD diagnosis in the subset of children with urinary concentrations of Cd, DEP, and TCP-246 above the 75th percentile. This study demonstrates a novel method that combines the inferential power of WQS and the predictive accuracy of machine-learning algorithms to discover potentially biologically relevant chemical-chemical interactions associated with ASD.


Asunto(s)
Trastorno del Espectro Autista , Plaguicidas , Oligoelementos , Niño , Humanos , Fenoles , Cadmio
5.
J Food Sci Technol ; 60(2): 679-691, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36712200

RESUMEN

To develop multi-antioxidant systems for the preservation of meat products, mixtures of essential oils or plant extracts were investigated for their antioxidant interactions. The combinatorial study revealed that the chemical diversity of both major and minor components of these ingredients contributed to the antioxidant interactions. A shift from antagonistic or additive interaction to synergistic one was achieved by modulating the ratio of mono-components of multi-antioxidant systems. Mixtures containing oregano/thyme (25/50 of IC50), thyme/clove (25/100) and thyme/cinnamon (50/25) oils as well as cranberry/rosemary (25/25), cranberry/green tea (25/25), cranberry/apple (25/25), rosemary/apple (50/25) and grapeseed/cranberry (50/50) extracts have shown synergistic antioxidant effects. Among the investigated systems, thyme/clove oils and oregano/thyme oils/grape-seed extract systems have extended, in situ, the shelf-life of chicken and ground pork products stored at 4 °C by 2 to 4 folds. The sensory acceptability of treated samples was rated to be moderately better than control. This study lays the ground for the development of efficient natural multi-antioxidant systems. Supplementary Information: The online version contains supplementary material available at 10.1007/s13197-022-05653-4.

6.
Small ; 18(12): e2106091, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34897990

RESUMEN

Atomic catalysts (AC) are gaining extensive research interest as the most active new frontier in heterogeneous catalysis due to their unique electronic structures and maximum atom-utilization efficiencies. Among all the atom catalysts, atomically dispersed heteronuclear dual-atom catalysts (HDACs), which are featured with asymmetric active sites, have recently opened new pathways in the field of advancing atomic catalysis. In this review, the up-to-date investigations on heteronuclear dual-atom catalysts together with the last advances on their theoretical predictions and experimental constructions are summarized. Furthermore, the current experimental synthetic strategies and accessible characterization techniques for these kinds of atomic catalysts, are also discussed. Finally, the crucial challenges in both theoretical and experimental aspects, as well as the future prospects of HDACs for energy-related applications are provided. It is believed that this review will inspire the rational design and synthesis of the new generation of highly effective HDACs.

7.
Angew Chem Int Ed Engl ; 61(40): e202207537, 2022 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-35894631

RESUMEN

Single-atom catalysts (SACs) are being pursued as economical electrocatalysts. However, their low active-site loading, poor interactions, and unclear catalytic mechanism call for significant advances. Herein, atomically dispersed Ni/Co dual sites anchored on nitrogen-doped carbon (a-NiCo/NC) hollow prisms are rationally designed and synthesized. Benefiting from the atomically dispersed dual-metal sites and their synergistic interactions, the obtained a-NiCo/NC sample exhibits superior electrocatalytic activity and kinetics towards the oxygen evolution reaction. Moreover, density functional theory calculations indicate that the strong synergistic interactions from heteronuclear paired Ni/Co dual sites lead to the optimization of the electronic structure and the reduced reaction energy barrier. This work provides a promising strategy for the synthesis of high-efficiency atomically dispersed dual-site SACs in the field of electrochemical energy storage and conversion.

8.
Chembiochem ; 22(3): 585-591, 2021 02 02.
Artículo en Inglés | MEDLINE | ID: mdl-32956537

RESUMEN

The self-assembly of short peptides into catalytic amyloid-like nanomaterials has proven to be a powerful tool in both understanding the evolution of early proteins and identifying new catalysts for practically useful chemical reactions. Here we demonstrate that both parallel and antiparallel arrangements of ß-sheets can accommodate metal ions in catalytically productive coordination environments. Moreover, synergistic relationships, identified in catalytic amyloid mixtures, can be captured in macrocyclic and sheet-loop-sheet species, that offer faster rates of assembly and provide more complex asymmetric arrangements of functional groups, thus paving the way for future designs of amyloid-like catalytic proteins. Our findings show how initial catalytic activity in amyloid assemblies can be propagated and improved in more-complex molecules, providing another link in a complex evolutionary chain between short, potentially abiotically produced peptides and modern-day enzymes.


Asunto(s)
Amiloide/síntesis química , Compuestos Organometálicos/química , Amiloide/química , Catálisis , Ciclización
9.
Environ Sci Technol ; 55(13): 9024-9032, 2021 07 06.
Artículo en Inglés | MEDLINE | ID: mdl-34125507

RESUMEN

Balkan endemic nephropathy (BEN) is a chronic tubulointerstitial nephropathy affecting residents of rural farming areas in many Balkan countries. Although it is generally believed that BEN is an environmental disease caused by multiple geochemical factors with much attention on aristolochic acids (AAs), its etiology remains controversial. In this study, we tested the hypothesis that environmental contamination and subsequent food contamination by polycyclic aromatic hydrocarbons (PAHs) and phthalate esters are AA toxicity factors and important to BEN development. We identified significantly higher concentrations of phenanthrene, anthracene, diethyl phthalate (DEP), dibutyl phthalate (DBP), and benzyl butyl phthalate (BBP) in both maize and wheat grain samples collected from endemic villages than from nonendemic villages. Other PAHs and phthalate esters were also detected at higher concentrations in the soil samples from endemic villages. Subsequent genotoxicity testing of cultured human kidney cells showed an alarming phenomenon that phenanthrene, DEP, BBP, and DBP can interact synergistically with AAs to form elevated levels of AA-DNA adducts, which are associated with both the nephrotoxicity and carcinogenicity of AAs, further increasing their disease risks. This study provides direct evidence that prolonged coexposure to these environmental contaminants via dietary intake may lead to greater toxicity and accelerated development of BEN.


Asunto(s)
Ácidos Aristolóquicos , Nefropatía de los Balcanes , Hidrocarburos Policíclicos Aromáticos , Ácidos Aristolóquicos/análisis , Ácidos Aristolóquicos/toxicidad , Nefropatía de los Balcanes/inducido químicamente , Nefropatía de los Balcanes/epidemiología , Peninsula Balcánica , Aductos de ADN , Ésteres , Humanos , Ácidos Ftálicos , Hidrocarburos Policíclicos Aromáticos/toxicidad , Suelo
10.
Mikrochim Acta ; 188(1): 17, 2021 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-33403455

RESUMEN

A synergistic imprinting strategy of covalent and non-covalent interactions is proposed to prepare magnetic molecularly imprinted polymers (DI-MMIPs) for highly selective separation of procyanidin B2 (PC) from grape seed samples. Dopamine and 3-amino-phenylboronic acid as cooperative functional monomers endow the imprinted sites with synergistic tailoring. Benefiting from the synergistic effect, the DI-MMIPs exhibit enhanced imprinting performance with high adsorption capacity (27.71 mg g-1), fast kinetic equilibrium time (within 30 min), outstanding selectivity (IF = 5.8, SC > 3.2), and satisfactory regeneration ability. In addition, the DI-MMIPs possess good magnetism, uniform morphology with typical core-shell structure, and stable crystallization. Furthermore, the established DI-MMIPs coupled with HPLC-UV (~ 280 nm) method has a wide linearity range of 0.05-200 µg mL-1 with correlation coefficient of 0.9997, high recoveries (> 93.1%) with RSDs from 2.9 to 5.5%, and low LOD (0.0008 µg mL-1). Consequently, this work provides an effective and easily tailored way to fabricate magnetic imprinted nanomaterials with both rapid recognition rate and high selectivity and thus holds great promise to realize the extraction and detection of PC from real samples.

11.
Chembiochem ; 21(18): 2611-2614, 2020 09 14.
Artículo en Inglés | MEDLINE | ID: mdl-32329215

RESUMEN

Interactions between multiple functional groups are key to catalysis. Previously, we reported synergistic interactions in catalytic amyloids formed by mixtures of heptameric peptides that lead to significant improvements in esterase activity. Herein, we describe the in-depth investigation of synergistic interactions within a family of amyloid fibrils, exploring the results of functional group interactions, the effects of chirality and the use of mixed enantiomers within fibrils. Remarkably, we find that synergistic interactions (either positive or negative) are found in the vast majority of binary mixtures of catalytic amyloid-forming peptides. The productive arrangements of functionalities rapidly identified by mixing different peptides will undoubtedly lead to the development of more active catalysts for a variety of different transformations.


Asunto(s)
Amiloide/química , Péptidos/química , Catálisis
12.
Arch Microbiol ; 202(6): 1439-1448, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32185411

RESUMEN

The present investigation aimed to evaluate antibacterial, antifungal and antioxidant efficacy of essential oils of three commonly used spices (black pepper, cinnamon and clove) in combination along with chemical characterization and toxicity evaluation. Among the possible combinations tested, cinnamon/clove oil combination showed synergistic antibacterial activity against foodborne bacteria Staphylococcus aureus, Listeria monocytogenes, Salmonella typhimurium and Pseudomonas aeruginosa and synergistic antifungal activity against Aspergillus niger as well as synergistic antioxidant potential in DPPH radical scavenging model system. GC-HRMS analysis revealed that out of thirteen identified components from clove oil, eugenol was found to be the main constituent of the oil; whereas out of twenty one identified constituents from cinnamon oil, the main component was cinnamaldehyde. Cinnamon/clove oil combination did not show any cytotoxic potential at recommended dosage level (IC50 > 2000 µg/ml). The results provide evidence that cinnamon/clove oil combination might indeed be used as a potential source of safe and effective novel natural antibacterial, antifungal and antioxidant blend in the food and pharmaceutical industries. To the best of our knowledge, this is the first time a combination of essential oils has been tested as natural preservatives to prevent both microbial proliferation and oxidative deterioration at sufficiently low concentrations.


Asunto(s)
Antibacterianos/farmacología , Antifúngicos/farmacología , Antioxidantes/farmacología , Aceite de Clavo/farmacología , Sinergismo Farmacológico , Aceites Volátiles/farmacología , Acroleína/análogos & derivados , Acroleína/farmacología , Aspergillus niger/efectos de los fármacos , Cinnamomum zeylanicum/química , Aceite de Clavo/química , Eugenol/farmacología , Listeria monocytogenes/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Piper nigrum/química , Pseudomonas aeruginosa/efectos de los fármacos , Salmonella typhimurium/efectos de los fármacos , Staphylococcus aureus/efectos de los fármacos , Syzygium/química
13.
Microb Ecol ; 80(4): 837-845, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32561944

RESUMEN

Soil microbes may greatly affect plant growth. While plants are commonly associated with diverse communities of soil microbes, complementary roles of different microbial communities that may stimulate synergistic effects on plant growth are not adequately tested. Also, such synergistic effects may vary with environmental conditions such as soil nutrient and water availability. We conducted a greenhouse experiment with a widespread clonal plant Solidago canadensis. The experiment was a factorial design with four levels of soil microbial inoculation (fresh soil inocula from grasslands in northern and southern China that were expected to differ in soil microbial composition, a mixture of the two fresh soil inocula, and a sterilized mixed inoculum control), two levels of nutrient availability (low vs. high), and two levels of water supply (low vs. high, i.e., 1376 vs. 352 mm per year). Irrespective of water supply and nutrient availability, total, aboveground, and belowground mass of S. canadensis were generally higher when the plant grew in soil inoculated with a mixture of soil microbes from the south and north of China (in the mixed inoculum treatment) than when it grew in soil inoculated with soil microbes from only the north or the south or the sterilized control. Such effects of soil microbes on total and aboveground mass were stronger under high than under low nutrient availability and also under high than under low water supply. Our results suggest that interactions of different soil microbial communities can result in a synergistic effect on plant growth and such a synergistic effect depends on environmental conditions. The findings shed light on the importance of plant-microbe interactions during the spreading of some plant species in face of increased atmospheric nutrient deposition coupled with altered rainfall pattern due to global change.


Asunto(s)
Microbiota , Nutrientes/metabolismo , Microbiología del Suelo , Suelo/química , Solidago/crecimiento & desarrollo , Agua/metabolismo
14.
Lett Appl Microbiol ; 71(2): 195-202, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32357268

RESUMEN

The aim of this study was to examine whether the process of initial colonization and the formation of mature biofilm structure of foodborne bacterial pathogens Listeria monocytogenes and Salmonella typhimurium can be impeded by active essential oil components ß-caryophyllene, cinnamaldehyde and eugenol at their individual and combined effects. Among the essential oil components tested, cinnamaldehyde and eugenol at their individual effect showed >50% degradation in biofilm biomass against preformed (matured) biofilms of both the studied bacteria, whereas ß-caryophyllene failed to do so. In combination, cinnamaldehyde/eugenol blend showed synergistic antibiofilm efficacy against preformed biofilms of both the studied bacteria L. monocytogenes (FICI: 0·24) and S. typhimurium (FICI: 0·40), whereas other tested combinations showed additive antibiofilm efficacy with FICI ranged from 2·02 to 2·35. Essential oil components alone and in combination also showed much higher inhibition effect on biofilm formation at the initial stage compared to their inhibition effect on preformed biofilms. The results provide evidence that cinnamaldehyde/eugenol combination may help in designing a more potent novel, natural antibiofilm blend at sufficiently low concentrations in the food and pharmaceutical industries. SIGNIFICANCE AND IMPACT OF THE STUDY: In the present work, synergistic antibiofilm efficacy of cinnamaldehyde/eugenol combination against established biofilms of foodborne bacterial pathogens Listeria monocytogenes and Salmonella typhimurium has been reported. These synergistic interactions may help in designing a more potent, safe and effective novel natural antibiofilm agent in food and pharmaceutical industries. Besides, this combination will also be helpful in reducing concentration of individual components, thereby minimizing the undesirable impact on sensory properties of food. To our knowledge, this is the first time, synergistic antibiofilm efficacy of cinnamaldehyde/eugenol blend against established biofilms of foodborne bacterial pathogens has been reported.


Asunto(s)
Acroleína/análogos & derivados , Antibacterianos/farmacología , Biopelículas/efectos de los fármacos , Listeria monocytogenes/efectos de los fármacos , Sesquiterpenos Policíclicos/farmacología , Salmonella typhimurium/efectos de los fármacos , Acroleína/farmacología , Eugenol/farmacología , Listeria monocytogenes/crecimiento & desarrollo , Pruebas de Sensibilidad Microbiana , Aceites Volátiles/farmacología , Salmonella typhimurium/crecimiento & desarrollo
15.
J Fish Dis ; 43(6): 651-664, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32315088

RESUMEN

Co-infections commonly arise when two or multiple different pathogens infect the same host, either as simultaneous or as secondary concurrent infection. This potentiates their pathogenic effects and leads to serious negative consequences on the exposed host. Numerous studies on the occurrence of the bacterial, parasitic, fungal and viral co-infections were conducted in various tilapia species. Co-infections have been associated with serious negative impacts on susceptible fish because they increase the fish susceptibility to diseases and the likelihood of outbreaks in the affected fish. Co-infections can alter the disease course and increase the severity of disease through synergistic and, more rarely, antagonistic interactions. In this review, reports on the synergistic co-infections and their impacts on the affected tilapia species are highlighted. Additionally, their pathogenic mechanisms are briefly discussed. Tilapia producers should be aware of the possible occurrence of co-infections and their effects on the affected tilapia species and in particular of the clinical signs and course of the disease. To date, there is still limited information regarding the pathogenicity mechanisms and pathogen interactions during these co-infections. This is generally due to low awareness regarding co-infections, and in many cases, a dominant pathogen is perceived to be of vital importance and hence becomes the target of treatment while the treatment of the co-infectious agents is neglected. This review article aimed at raising awareness regarding co-infections and helping researchers and fish health specialists pay greater attention to these natural cases, leading to increased research and more consistent diagnosis of co-infectious outbreaks in order to improve control strategies to protect tilapia when infected with multiple pathogens.


Asunto(s)
Coinfección/veterinaria , Brotes de Enfermedades/veterinaria , Enfermedades de los Peces , Tilapia , Animales , Coinfección/epidemiología , Coinfección/etiología , Coinfección/prevención & control , Enfermedades de los Peces/epidemiología , Enfermedades de los Peces/etiología , Enfermedades de los Peces/prevención & control , Enfermedades de los Peces/transmisión
16.
Chem Biodivers ; 17(6): e1900507, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32277597

RESUMEN

The effect of a natural sesquiterpene ketone, 9,10-dehydrofukinone (DHF), on pathogenic Staphylococcus aureus and Pseudomonas aeruginosa strains isolated from chronic infectious processes, was the focus of the present study. Lipophilic DHF produced important antibacterial synergistic effects in association with ciprofloxacin (CPX) against two biofilm-forming strains of S. aureus HT1 (FIC=0.21) and P. aeruginosa HT5 (FIC=0.05). Hence, this mixture constitutes an excellent strategy to combat these biofilm-producing bacteria that overexpress drug efflux pumps as a resistance mechanism. Additionally, a substantial rise in beneficial Lactobacillus biofilm biomass was determined as a very significant finding of this association. Particularly, a non-pathogenic biofilm increment of 119 % was quantified when the mixture was added to a probiotic L. acidophilus ATCC SD-5212 culture. A surface activity enhanced in 71 % with respect to untreated L. acidophilus culture was also generated by the DHF and CPX association, and therefore, a glycoprotein synthesis induction mediated by the mixture is discussed. The results obtained could help in the development of new selective antibiotics. From an ecological standpoint, the present study strongly suggests that DHF is a polyfunctional organic molecule produced with a high yield in Senecio punae that exerts a positive impact on a non-pathogenic plant bacterium L. plantarum CE105.


Asunto(s)
Senecio/química , Sesquiterpenos/química , Compuestos Orgánicos Volátiles/química , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Antibacterianos/farmacología , Biopelículas/efectos de los fármacos , Ciprofloxacina/farmacología , Lactobacillus/efectos de los fármacos , Lactobacillus/fisiología , Pruebas de Sensibilidad Microbiana , Pseudomonas aeruginosa/efectos de los fármacos , Pseudomonas aeruginosa/aislamiento & purificación , Pseudomonas aeruginosa/fisiología , Senecio/metabolismo , Sesquiterpenos/aislamiento & purificación , Sesquiterpenos/farmacología , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/aislamiento & purificación , Staphylococcus aureus/fisiología
17.
Molecules ; 25(16)2020 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-32784994

RESUMEN

The aroma of an instant white tea (IWT) was extracted through simultaneous distillation-extraction (SDE) and analyzed by sensory evaluation, gas chromatography-mass spectrometry-olfactometry (GC-MS-O), aroma reconstruction, omission test and synergistic interaction analysis. Sensory evaluation showed the IWT was dominated with floral and sweet notes. The SDE extract had the aroma similar to the IWT. The main volatile components in the SDE extract were benzyl alcohol, linalool, hotrienol, geraniol, α-terpineol, coumarin, camphene, benzeneacetaldehyde, 2-hexanone, cis-jasmin lactone and phenylethyl alcohol. GC-MS-O and aroma reconstruction experiments showed 16 aroma-active compounds. Linalool, trans-ß-damascenone and camphene were the major contributors to floral, sweet and green notes based on flavor dilution analysis and omission test. Linalool and trans-ß-damascenone had synergistic effect to promote floral and sweet notes. Camphene and trans-ß-damascenone had synergistic effect to reduce green and sweet notes. The study helps to understand the aroma of IWT and antagonism interactions among aroma-active volatiles.


Asunto(s)
Cromatografía de Gases y Espectrometría de Masas , Odorantes/análisis , Té/química , Compuestos Orgánicos Volátiles/química , Adulto , Destilación , Femenino , Liofilización , Humanos , Masculino , Olfatometría , Microextracción en Fase Sólida , Umbral Gustativo , Té/metabolismo , Compuestos Orgánicos Volátiles/aislamiento & purificación , Adulto Joven
18.
Neurobiol Dis ; 125: 135-145, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30716469

RESUMEN

Endocannabinoids (eCBs) and serotonin (5-HT) play a neuromodulatory role in the central nervous system. Both eCBs and 5-HT regulate neuronal excitability and their pharmacological potentiation has been shown to control seizures in pre-clinical and human studies. Compelling evidence indicates that eCB and 5-HT systems interact to modulate several physiological and pathological brain functions, such as food intake, pain, drug addiction, depression, and anxiety. Nevertheless, there is no evidence of an eCB/5-HT interaction in experimental and human epilepsies, including status epilepticus (SE). Here, we performed video-EEG recording in behaving rats treated with the pro-convulsant agent pilocarpine (PILO), in order to study the effect of the activation of CB1/5-HT2 receptors and their interaction on SE. Synthetic cannabinoid agonist WIN55,212-2 (WIN) decreased behavioral seizure severity of PILO-induced SE at 2 mg/kg (but not at 1 and 5 mg/kg, i.p.), while 5-HT2B/2C receptor agonist RO60-0175 (RO; 1, 3, 10 mg/kg, i.p.) was devoid of any effect. RO 3 mg/kg was instead capable of potentiating the effect of WIN 2 mg/kg on the Racine scale score. Surprisingly, neither WIN 2 mg/kg nor RO 3 mg/kg had any effect on the incidence and the intensity of EEG seizures when administered alone. However, WIN+RO co-administration reduced the incidence and the severity of EEG SE and increased the latency to SE onset after PILO injection. WIN+RO effects were blocked by the selective CB1R antagonist AM251 and the 5-HT2BR antagonist RS127445, but not by the 5-HT2CR antagonist SB242084 or the 5-HT2AR antagonist MDL11,939. These data revealed a synergistic interaction between CB1R/5-HT2BR in the expression of PILO-induced SE.


Asunto(s)
Receptor Cannabinoide CB1/metabolismo , Receptor de Serotonina 5-HT2B/metabolismo , Estado Epiléptico/metabolismo , Animales , Benzoxazinas/farmacología , Bloqueadores de los Canales de Calcio/farmacología , Masculino , Morfolinas/farmacología , Agonistas Muscarínicos/toxicidad , Naftalenos/farmacología , Pilocarpina/toxicidad , Ratas , Ratas Sprague-Dawley , Receptor Cannabinoide CB1/efectos de los fármacos , Receptor de Serotonina 5-HT2B/efectos de los fármacos , Agonistas del Receptor de Serotonina 5-HT2/farmacología , Estado Epiléptico/inducido químicamente
19.
Glob Chang Biol ; 25(12): 4131-4146, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31482629

RESUMEN

Global climate change has profound implications on species distributions and ecosystem functioning. In the coastal zone, ecological responses may be driven by various biogeochemical and physical environmental factors. Synergistic interactions can occur when the combined effects of stressors exceed their individual effects. The Red Sea, characterized by strong gradients in temperature, salinity, and nutrients along the latitudinal axis provides a unique opportunity to study ecological responses over a range of these environmental variables. Using multiple linear regression models integrating in situ, satellite and oceanographic data, we investigated the response of coral reef taxa to local stressors and recent climate variability. Taxa and functional groups responded to a combination of climate (temperature, salinity, air-sea heat fluxes, irradiance, wind speed), fishing pressure and biogeochemical (chlorophyll a and nutrients - phosphate, nitrate, nitrite) factors. The regression model for each species showed interactive effects of climate, fishing pressure and nutrient variables. The nature of the effects (antagonistic or synergistic) was dependent on the species and stressor pair. Variables consistently associated with the highest number of synergistic interactions included heat flux terms, temperature, and wind speed followed by fishing pressure. Hard corals and coralline algae abundance were sensitive to changing environmental conditions where synergistic interactions decreased their percentage cover. These synergistic interactions suggest that the negative effects of fishing pressure and eutrophication may exacerbate the impact of climate change on corals. A high number of interactions were also recorded for algae, however for this group, synergistic interactions increased algal abundance. This study is unique in applying regression analysis to multiple environmental variables simultaneously to understand stressor interactions in the field. The observed responses have important implications for understanding climate change impacts on marine ecosystems and whether managing local stressors, such as nutrient enrichment and fishing activities, may help mitigate global drivers of change.


Asunto(s)
Antozoos , Arrecifes de Coral , Animales , Clorofila A , Cambio Climático , Ecosistema , Océano Índico
20.
Chemistry ; 24(9): 2157-2163, 2018 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-29205557

RESUMEN

The route of converting CO2 to CO by reverse water-gas shift (RWGS) reaction is of particular interest due to the direct use of CO as feedstock in many significant industrial processes. Here, an engineered cobalt-cobalt oxide core-shell catalyst (Co@CoO) with nanochains structure has been made for the efficient reduction of CO2 to useful CO. Owing to the excellent performance for H2 activation of metal nanoparticles and the enhanced absorption and activation for CO2 molecule of defective metal oxides, the unique synergistic effect of metallic Co and encapsulating coordinatively unsaturated CoO species shows high performance for clean generation of CO under moderate and practical conditions. Furthermore, with N-dopant into the defective CoO shell, the Co@CoO-N achieves the highest conversion of 19.2 % and an exceptional CO evolution rate of 96 mL min-1 gcat-1 at 523 K with a gas hourly space velocity (GHSV) of 42,000 mL gcat-1 h-1 , which is comparable with the previously reported materials under identical conditions.

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