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1.
Org Biomol Chem ; 20(6): 1306-1314, 2022 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-35075474

RESUMO

Orbitides are bioactive head-to-tail natural cyclic peptides from plant species. Their bioactivity is intrinsically related to the main conformations adopted in solution, whose correct characterization represents an important bottleneck for medicinal chemistry applications. To date, NMR spectrosocopy has been the most frequently used technique to assess the secondary structure of orbitides. Despite the amount of structural information commonly available from NMR, its time scale frequently results in a limited conformational ensemble with a single mean structure, which may not represent the bioactive conformation. Additionally, problems with inter-residue NOE/ROE signals can reduce the accuracy and confidence of the 3D assignments. Vibrational circular dichroism (VCD), on the other hand, has been demostrated as a powerful tool to probe the stereostructure of chiral molecules, including peptides and proteins, with enhanced sensitivity to individual conformations in the condensed phase. Herein, we present the first VCD stereochemical investigation of orbitides. By combining IR/VCD experiments in ACN-d3 and ACN-d3/D2O mixtures with DFT calculations in different levels of theory we were able to determine the solution-state conformational behavior, as well as the main structural restraints induced by cyclization, of the seven-residue orbitide pohlianin A and its linear precursor. VCD results indicated inverse γ-turns as the most prevalent structural motif for the linear precursor in partially aqueous solution, while type I and type VI ß-turns were induced by the cyclization process, along with some classic γ-turns. In addition to the conformation of the cyclic peptide already described from NMR data, two previously unidentified conformations with distinct secondary structures were found to significantly populate the sample. This conformational discriminatory power of VCD for both linear and cyclic peptides in different solvent systems may lead to more accurate structural characterization of turn-rich peptidic natural products and help the design of conformationally-tailored peptides for more precise structure-activity relationship results.

2.
J Environ Sci Health B ; 57(7): 554-560, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35583269

RESUMO

Tetraethyl pyrophosphate (TEPP) is an organophosphate pesticide that irreversibly inhibits acetylcholinesterase (AChE). Cork powder or granules have been recommended as a sustainable sorbent to remove pesticides from water. In the present study, we evaluated the effectiveness of removing TEPP from water using wine corks to obtain cork granules as natural adsorbent, analyzing the TEPP effects on AChE activity in commercial enzyme from Electrophorus electricus and secreted by neuronal PC12 cells. TEPP inhibited AChE activity in a concentration-dependent manner. For the first time, we showed that different concentrations of TEPP diluted in water after adsorption experiments using cork granules decreased TEPP's inhibitory effects on AChE activity in commercial enzyme and neuronal PC12 cell culture medium. Our results suggest that the optimum removal of TEPP from water by corks was 91.4 ± 4.0%. Overall, the findings support the hypothesis that cork granules can be used to remediate pesticide-contaminated environments, such as those contaminated by organophosphate pesticides, and demonstrate a new application of a biochemical assay on AChE activity using a commercial enzyme or secreted by neuronal PC12 cells in culture as a possible methodologic strategy for evaluating the success of TEPP removal from water.


Assuntos
Acetilcolinesterase , Praguicidas , Animais , Organofosfatos , Compostos Organofosforados , Células PC12 , Praguicidas/farmacologia , Ratos , Água
3.
Int J Mol Sci ; 22(11)2021 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-34200414

RESUMO

Numerous environmental and endogenous factors affect the level of genetic diversity in natural populations. Genetic variability is the cornerstone of evolution and adaptation of species. However, currently, more and more plant species and local varieties (landraces) are on the brink of extinction due to anthropopression and climate change. Their preservation is imperative for the sake of future breeding programs. Gene banks have been created worldwide to conserve different plant species of cultural and economic importance. Many of them apply cryopreservation, a conservation method in which ultra-low temperatures (-135 °C to -196 °C) are used for long-term storage of tissue samples, with little risk of variation occurrence. Cells can be successfully cryopreserved in liquid nitrogen (LN) when the adverse effect of ice crystal formation and growth is mitigated by the removal of water and the formation of the so-called biological glass (vitrification). This state can be achieved in several ways. The involvement of key cold-regulated genes and proteins in the acquisition of cold tolerance in plant tissues may additionally improve the survival of LN-stored explants. The present review explains the importance of cryostorage in agronomy and presents an overview of the recent works accomplished with this strategy. The most widely used cryopreservation techniques, classic and modern cryoprotective agents, and some protocols applied in crops are considered to understand which parameters provide the establishment of high quality and broadly applicable cryopreservation. Attention is also focused on the issues of genetic integrity and functional genomics in plant cryobiology.


Assuntos
Produtos Agrícolas/crescimento & desenvolvimento , Criopreservação/métodos , Crioprotetores/farmacologia , Melhoramento Vegetal , Brotos de Planta/crescimento & desenvolvimento , Sementes/crescimento & desenvolvimento , Vitrificação , Protoplastos
4.
J Environ Sci Health B ; 56(7): 670-674, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34157949

RESUMO

Paraquat is resistant to degradation by conventional treatments, being necessary to use treatments with greater effectiveness, such as advanced oxidative processes. In this work, different advanced oxidative processes were applied (Fenton, electro-Fenton, photoelectro-oxidation and photoelectro-Fenton) employing oxide electrodes to degrade Gramoxone, a commercial herbicide that contains paraquat in its composition. The degradation and formation of by-products were accompanied by high performance liquid chromatography, total organic carbon (TOC) and chemical oxygen demand (COD). The results showed that the photoelectro-Fenton process was the most efficient due to the synergistic effect, reaching 79% degradation of the initial compound and 82% and 71% removal of TOC and COD, respectively. After the application of the electro-Fenton and photoelectro-Fenton oxidation processes, short-chain carboxylic acids such as succinic acid, oxalic acid, acetic acid and formic acid were identified as by-products of the oxidation of Gramoxone. The results were satisfactory and deserve to be highlighted, as a commercial formulation was used, making the scenario more realistic.


Assuntos
Herbicidas , Poluentes Químicos da Água , Eletrodos , Peróxido de Hidrogênio , Oxirredução , Estresse Oxidativo , Paraquat
5.
Nanotechnology ; 31(16): 165501, 2020 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-31770731

RESUMO

Cyclodextrin (CD) is a conical compound used in food and pharmaceutical industry to complexation of hydrophobic substances. It is a product of microbial enzymes which converts starch into CD during their activity. We aim to detect CD using active-electrode biosensor of SnO2. They were grown on active electrode by the VLS method. The CD consists of several glucose units which have hydroxyl groups which tend to bind to interface states present in nanowires changing their conductivity. Experimental results of electrical conductivity at different CD concentrations are presented. A model that describes the influence of adsorbed glucose on nanowires and its electrical properties is also presented. Some general observations are performed on the applicability of the CD adsorption method by the nanowire-based biosensor.


Assuntos
Técnicas Biossensoriais , Ciclodextrinas/análise , Glucosiltransferases/metabolismo , Nanofios/química , Compostos de Estanho/química , Bacillus/enzimologia , Eletricidade , Eletrodos , Nanofios/ultraestrutura , Fatores de Tempo
6.
Neurourol Urodyn ; 35(7): 847-50, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-26179109

RESUMO

OBJECTIVES: To validate in Spanish (Spain) a self-administered questionnaire on the quality of life (QoL) specific to nocturia in an older adult male population. MATERIAL AND METHODS: We analysed the Spanish version of the ICIQ-Nqol questionnaire (provided by ICIQ who owns the copyright), which meets the translation criteria required by the validation protocol. The study included 69 male patients older than 60 years of age with 1 or more nocturia episodes. The participants completed the questionnaire on two occasions, along with other Spanish-validated questionnaires that measure the QoL related to urinary symptoms. We analysed the internal reliability and consistency, reproducibility, convergent validity and discriminant validity. RESULTS: The study included 69 men, with a mean age of 70.64 years (range, 60-87 years). Both the overall scale and the energy/sleep subscale met the minimum criteria for internal reliability and consistency. A good correlation has been demonstrated between the overall index of the ICIQ-Nqol questionnaire and the other questionnaires included in the study. The reproducibility (test-retest reliability) of both the overall scale and subscales of the ICIQ-Nqol and the other questionnaires was demonstrated. Conclusions The ICIQ-Nqol questionnaire has been shown to be an appropriate instrument for assessing the symptomatic intensity and impact on the QoL of patients with nocturia. This study confirms its validity for a Spanish-speaking male population. Neurourol. Urodynam. 35:847-850, 2016. © 2015 Wiley Periodicals, Inc.


Assuntos
Noctúria/diagnóstico , Qualidade de Vida , Inquéritos e Questionários , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Reprodutibilidade dos Testes , Espanha , Avaliação de Sintomas , Traduções
7.
J Food Sci ; 89(5): 2774-2786, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38602038

RESUMO

Banana is one of the most consumed and popular fruits in all regions of the world, being cultivated mainly in tropical countries. It is not only a rich source of vitamins A, C, and B, calcium, iron, potassium, phosphorus, and other vitamins and nutrients, but it also contains several types of antioxidants with high nutritional value. In this context, the current study aimed to quantify the content of ascorbic acid, flavonoids, pigments, and minerals present in "Nanicão" bananas during the ripening process. As demonstrated, the level of flavonoids was higher in ripe and overripe fruits, whereas the mineral composition was high only at ripening stage 4 (more yellow than green) a stage that should be prioritized when recommending fruit consumption to the population deficient in these minerals. Regarding pigments, there was a reduction in chlorophylls a and b and an increase in carotenoids and anthocyanins in peels and pulps. PRACTICAL APPLICATION: Flavonoids are phenolic, bioactive compounds with proven antioxidant and anti-inflammatory activity and products of the plant's secondary metabolism. The degradation of chlorophylls and synthesis of carotenoids and anthocyanins, and as a consequence of the latter pigment, the increase in flavonoids in the pulp was evident during the monitoring of ripening, mainly in the fruit peels in relation to pigments. Minerals are essential elements, the main ones provided in balanced diets and important for dietary and nutritional health.


Assuntos
Antioxidantes , Carotenoides , Flavonoides , Frutas , Minerais , Musa , Flavonoides/análise , Frutas/química , Musa/química , Minerais/análise , Antioxidantes/análise , Carotenoides/análise , Pigmentos Biológicos/análise , Clorofila/análise , Ácido Ascórbico/análise , Valor Nutritivo , Antocianinas/análise
8.
Microbiol Spectr ; 12(5): e0407823, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38534121

RESUMO

Parasiticide fungi are considered an accurate, sustainable, and safe solution for the biocontrol of animal gastrointestinal (GI) parasites. This research provides an initial characterization of the virulence of the native parasiticide fungus Mucor circinelloides (FMV-FR1) and an assessment of its impact on birds' gut microbes. The genome of this fungus was sequenced to identify the genes coding for virulence factors. Also, this fungus was checked for the phenotypic expression of proteinase, lecithinase, DNase, gelatinase, hemolysin, and biofilm production. Finally, an in vivo trial was developed based on feeding M. circinelloides spores to laying hens and peacocks three times a week. Bird feces were collected for 3 months, with total genomic DNA being extracted and subjected to long-read 16S and 25S-28S sequencing. Genes coding for an iron permease (FTR1), iron receptors (FOB1 and FOB2), ADP-ribosylation factors (ARFs) (ARF2 and ARF6), and a GTPase (CDC42) were identified in this M. circinelloides genome. Also, this fungus was positive only for lecithinase activity. The field trial revealed a fecal microbiome dominated by Firmicutes and Proteobacteria in laying hens, and Firmicutes and Bacteroidetes in peacocks, whereas the fecal mycobiome of both bird species was mainly composed of Ascomycetes and Basidiomycetes fungi. Bacterial and fungal alpha-diversities did not differ between sampling time points after M. circinelloides administrations (P = 0.62 and P = 0.15, respectively). Although findings from this research suggest the lack of virulence of this M. circinelloides parasiticide isolate, more complementary in vitro and in vivo research is needed to conclude about the safety of its administration to birds, aiming at controlling their GI parasites.IMPORTANCEA previous study revealed that the native Mucor circinelloides isolate (FMV-FR1) can develop parasiticide activity toward coccidia oocysts, one of the most pathogenic GI parasites in birds. However, ensuring its safety for birds is of utmost importance, namely by studying its virulence profile and potential effect on commensal gut microbes. This initial study revealed that although this M. circinelloides isolate had genes coding for four types of virulence factors-iron permease, iron receptors, ADP-ribosylation factors, and GTPase-and only expressed phenotypically the enzyme lecithinase, the administration of its spores to laying hens and peacocks did not interfere with the abundances and diversities of their gut commensal bacteria and fungi. Although overall results suggest the lack of virulence of this M. circinelloides isolate, more complementary research is needed to conclude about the safety of its administration to birds in the scope of parasite biocontrol programs.


Assuntos
Galinhas , Microbioma Gastrointestinal , Mucor , Fatores de Virulência , Mucor/genética , Mucor/patogenicidade , Animais , Galinhas/microbiologia , Virulência , Fatores de Virulência/genética , Fatores de Virulência/metabolismo , Fezes/microbiologia , Feminino
9.
Environ Sci Pollut Res Int ; 31(15): 22994-23010, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38413525

RESUMO

The historical impacts of eutrophication processes were investigated in six subtropical reservoirs (São Paulo, Brazil) using a paleolimnological approach. We questioned whether the levels of pigment indicators of algal biomass could provide information about trophic increase and whether carotenoid pigments could offer additional insights. The following proxies were employed: organic matter, total phosphorus, total nitrogen, photosynthetic pigments (by high-performance liquid chromatography), sedimentation rates, and geochronology (by 210 Pb technique). Principal component analysis indicated a gradient of eutrophication. In eutrophic reservoirs (e.g., Rio Grande and Salto Grande), levels of lutein and zeaxanthin increased over time, suggesting growth of Chlorophyta and Cyanobacteria. These pigments were significantly associated with algal biomass, reflecting their participation in phytoplankton composition. In mesotrophic reservoirs, Broa and Itupararanga, increases and significative linear correlations (r > 0.70) between pigments and nutrients are mainly linked to agricultural and urban activities. In the oligotrophic reservoir Igaratá, lower pigment and nutrient levels reflected lesser human impact and good water quality. This study underscores eutrophication's complexity across subtropical reservoirs. Photosynthetic pigments associated with specific algal groups were informative, especially when correlated with nutrient data. The trophic increase, notably in the 1990s, may have been influenced by neoliberal policies. Integrated pigment and geochemical analysis offers a more precise understanding of eutrophication changes and their ties to human factors. Such research can aid environmental monitoring and sustainable policy development.


Assuntos
Clorofila , Qualidade da Água , Humanos , Clorofila/análise , Brasil , Fitoplâncton , Monitoramento Ambiental , Eutrofização , Fósforo/análise , Nitrogênio/análise , China
10.
Parasitol Int ; 98: 102808, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37717651

RESUMO

The mortality rate caused by parasitic worms on their hosts is of great concern and studies have been carried out to find molecules to reduce the prevalence, host-parasite interaction, and resistance of parasites to treatments. Existing drugs on the market are very often toxic and have many side effects, hence the need to find new, more active molecules. It has been demonstrated in several works that medicinal plants constitute a wide range of new molecules that can solve this problem. Several works have already been able to demonstrate that cyclic peptides of plant origin have shown good activity in the fight against different types of helminths. Therefore, this review aims to provide a general overview of the methods and techniques of extraction, isolation, activities and mechanisms of action of cyclotides and other cyclic peptides for application in the treatment of helminthic infections.


Assuntos
Ciclotídeos , Parasitos , Plantas Medicinais , Animais , Ciclotídeos/farmacologia , Ciclotídeos/química , Peptídeos Cíclicos/farmacologia , Plantas Medicinais/química
11.
Sci Rep ; 14(1): 11352, 2024 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-38762506

RESUMO

The biological control of gastrointestinal (GI) parasites using predatory fungi has been recently proposed as an accurate and sustainable approach in birds. The current study aimed to assess for the first time the efficacy of using the native ovicidal fungus Mucor circinelloides (FMV-FR1) in reducing coccidia parasitism in peacocks. For this purpose, an in vivo trial was designed in the resident peacock collection (n = 58 birds) of the São Jorge Castle, at Lisbon, Portugal. These animals presented an initial severe infection by coccidia of the genus Eimeria (20106 ± 8034 oocysts per gram of feces, OPG), and thus received commercial feed enriched with a M. circinelloides suspension (1.01 × 108 spores/kg feed), thrice-weekly. Fresh feces were collected every 15 days to calculate the coccidia shedding, using the Mini-FLOTAC technique. The same bird flock served simultaneously as control (t0 days) and test groups (t15-t90 days). The average Eimeria sp. shedding in peacocks decreased up to 92% following fungal administrations, with significant reduction efficacies of 78% (p = 0.004) and 92% (p = 0.012) after 45 and 60 days, respectively. Results from this study suggest that the administration of M. circinelloides spores to birds is an accurate solution to reduce their coccidia parasitism.


Assuntos
Coccidiose , Fezes , Mucor , Animais , Coccidiose/veterinária , Coccidiose/parasitologia , Fezes/parasitologia , Fezes/microbiologia , Eimeria , Coccídios , Doenças das Aves Domésticas/parasitologia , Doenças das Aves Domésticas/microbiologia , Doenças das Aves Domésticas/prevenção & controle
12.
Insects ; 15(1)2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38249073

RESUMO

The Varroa destructor mite infests Apis mellifera colonies and causes significant harm. Traditional treatments have become less effective because of mite resistance development and can also generate residues inside beehives. This study aimed to gauge the efficacy of a beehive-derived postbiotic in reducing V. destructor viability and to explore its synergies with organic compounds. Four lactic acid bacteria (LAB) species, Leuconostoc mesenteroides, Lactobacillus helsingborgensis, Bacillus velezensis, and Apilactobacillus kunkeei, were isolated and tested in a postbiotic form (preparations of inanimate microorganisms and/or their components) via bioassays. L. mesenteroides, L. helsingborgensis, and B. velezensis notably reduced the mite viability compared to the control, and they were further tested together as a single postbiotic product (POS). Further bioassays were performed to assess the impact of the POS and its combinations with oxalic acid and oregano essential oil. The simple products and combinations (POS/Oregano, POS/Oxalic, Oregano/Oxalic, and POS/Oregano/Oxalic) decreased the mite viability. The most effective were the oxalic acid combinations (POS/Oregano/Oxalic, Oxalic/Oregano, POS/Oxalic), showing significant improvements compared to the individual products. These findings highlight the potential of combining organic products as a vital strategy for controlling V. destructor infection. This study suggests that these combinations could serve as essential tools for combating the impact of mites on bee colonies.

13.
Res Vet Sci ; 169: 105173, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38335895

RESUMO

Colony collapse disorder (CCD) has affected bees worldwide in recent decades, with southwestern Spain being no exception. This disorder is one of the main causes of Apis mellifera mortality and is believed to be caused by environmental, social and sanitary conditions. Dietary supplementation can help to improve some parameters of the general status and sanitary condition of bees, such as infestation by certain recurrent pathogens, including Varroa destructor and Nosema ceranae, by enhancing immune and social response. Thus, the aim of this study was to test a liquid hydrolysed protein supplement on the health and general status of the hive in several apiaries with access to the same natural food and under similar climatic conditions. We selected two groups of ten hives (supplemented by either placebo or protein) from five apiaries where the number of adult bees, amount of brood (open and operculated), honey and pollen reserves, infestation by V. destructor, N. ceranae, deformed wing virus (DWV) and chronic bee paralysis virus (CBPV) were measured. Additionally, we assess the expression of four immune system-related genes and a gene encoding vitellogenin. At the end of this work, treated hives showed a significant increase in open brood and a decrease in V. destructor infestation. Also, these hives showed a significant decrease in the mortality rate after the cold season. Therefore, supplementation with this product improved the health of the hive and could be a promising tool against bee colony loss.


Assuntos
Mel , Vírus de RNA , Urticária , Varroidae , Abelhas , Animais , Espanha/epidemiologia , Varroidae/fisiologia , Urticária/veterinária , Suplementos Nutricionais
14.
Food Res Int ; 167: 112697, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37087263

RESUMO

A protocol was optimized to determine the volatile profile from monovarietal virgin olive oil (VOO) by multiple headspace solid-phase microextraction (MHS-SPME) followed by gas chromatography-mass spectrometry (GC-MS) analysis. For this, a Plackett-Burman (PB) and central composite rotational designs (CCRD) were used to define the best condition of extraction. Moreover, fatty acids profile and principal component analysis (PCA) was used to identify markers among the cultivars. The amount of 0.1 g of sample was enough to express the volatile composition of the olive oils by MHS-SPME. Volatile compounds [nonanal, (Z)-3-Hexen-1-ol, (Z)-3-Hexenyl Acetate, Hexyl Acetate, 3-Methylbutyl Acetate, (E)-2-Hexen-1-ol, (E)-2-Hexenyl Acetate] and fatty acids [C17:1, C18, C18:1, C18:2] were those reported such as the markers in the varieties of olive oils. The PCA analysis allowed the classification of the most representative volatiles and fatty acids for each cultivar. Through two principal components was possible to obtain 81.9% of explanation of the variance of the compounds. The compounds were quantified using a validated method. The MHS-SPME combined with multivariate analysis showed a promising tool to identify markers and for the discrimination of olive oil varieties.


Assuntos
Microextração em Fase Sólida , Compostos Orgânicos Voláteis , Microextração em Fase Sólida/métodos , Azeite de Oliva/química , Brasil , Quimiometria , Compostos Orgânicos Voláteis/análise , Ácidos Graxos/análise
15.
Front Microbiol ; 14: 1223717, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37533825

RESUMO

Introduction: High quality corn silage depends on factors such as corn type, stage of crop development at harvest time, fermentation time, in addition to use or not of inoculants. This study aimed to investigate the impact of maturity stage, bacterial inoculation, and storage time on fermentation, aerobic stability, and nutritional characteristics of flint corn silage and their implications for corn silage management. Methods: A flint corn hybrid was harvested very early, early, and medium (at 250, 300 and 350 g dry matter (DM)/kg as fed, respectively) and ensiled in mini-silos without (control) or with Lentilactobacillus buchneri CNCM I-4323 at 1 × 105 cfu/g for 120, 240 and 360 d to investigate how these factors interact with each other. Results and discussion: There was only a small increase (7 g/kg starch; p = 0.003) in starch digestibility (starch-D) in the silages stored for 360 d when compared to that stored for 240 d, but with no difference for 120 d. Despite the reduced starch-D (526 vs. 694 g/kg starch; p < 0.001), silages produced from medium harvest had higher (p < 0.001) starch content (317 vs. 137 g/kg DM) and higher amount of digestible starch (169 vs. 98.5 g/kg DM; p < 0.001) compared to very early harvest. The 2-way interactions (inoculation × storage time and maturity × storage time) showed that inoculation of corn silage with L. buchneri increased (p < 0.001) the aerobic stability, and that more mature crop silage had higher aerobic stability (140 h; p = 0.036) than the others (118 and 48.5 h for those silages from very early and early harvest). Conclusion: The storage for a longer time (>120 d) with the goal of increasing silage digestibility did not occur. Harvesting whole-crop flint corn with 300 to 350 g/kg DM is desirable to have higher DM yield and starch accumulation. Inoculation with L. buchneri is recommended to preserve the silage against aerobic deterioration. This study has shown the importance of harvesting flint corn at the right time, and the need for inoculation with L. buchneri to ensure greater yield, starch accumulation, and silage preservation, if 120 days of storage are not exceeded.

16.
Sci Rep ; 13(1): 8586, 2023 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-37236996

RESUMO

We have conducted a monitoring survey and paleolimnological study of a W-E transect of six high altitude lakes (1870-2630 m asl) in the western and central Pyrenees (Spain) to evaluate the regional response to current global change in high altitude Mediterranean mountains. The reconstructed Total Organic Carbon (TOCflux) and lithogenic (Lflux) fluxes during the last 1200 years show the expected variability as lakes differ in altitude, geological and climate settings, limnological properties and human impact history. However, all show unique patterns after 1850 CE, particularly during the Great Acceleration (after 1950 CE). Recent Lflux increase could be related to higher erodibility by rainfall and run-off during the longer snow-free season in the Pyrenees. In all sites, higher TOCflux and geochemical (lower δ13COM, lower C/N) and biological (diatom assemblages) signatures since 1950 CE suggest an increase in algal productivity, likely favored by warmer temperatures and higher nutrient deposition. These recent, unprecedented Lflux and TOCflux increases, in spite of their diverse history and limnological properties of the lakes, demonstrate the regional impact of the Great Acceleration not only in the ecological dynamics of alpine lakes but also in the hydrological cycle in high altitude mountain watersheds.

17.
Plant Physiol Biochem ; 201: 107869, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37421847

RESUMO

Studies on the role of nickel (Ni) in photosynthetic and antioxidant metabolism, as well as in flavonoid synthesis and biological fixation nitrogen in cowpea crop are scarce. The aim of this study was to elucidate the role of Ni in metabolism, photosynthesis and nodulation of cowpea plants. A completely randomized experiment was performed in greenhouse, with cowpea plants cultivated under 0, 0.5, 1, 2, or 3 mg kg-1 Ni, as Ni sulfate. In the study the following parameters were evaluated: activity of urease, nitrate reductase, superoxide dismutase, catalase and ascorbate peroxidase; concentration of urea, n-compounds, photosynthetic pigments, flavonoids, H2O2 and MDA; estimative of gas exchange, and biomass as plants, yield and weight of 100 seeds. At whole-plant level, Ni affected root biomass, number of seeds per pot, and yield, increasing it at 0.5 mg kg-1 and leading to inhibition at 2-3 mg kg-1 (e.g. number of seeds per pot and nodulation). The whole-plant level enhancement by 0.5 mg Ni kg-1 occurred along with increased photosynthetic pigments, photosynthesis, ureides, and catalase, and decreased hydrogen peroxide concentration. This study presents fundamental new insights regarding Ni effect on N metabolism, and nodulation that can be helpful to increase cowpea yield. Considering the increasing population and its demand for staple food, these results contribute to the enhancement of agricultural techniques that increase crop productivity and help to maintain human food security.


Assuntos
Vigna , Humanos , Catalase/metabolismo , Vigna/metabolismo , Fixação de Nitrogênio , Níquel/farmacologia , Níquel/metabolismo , Peróxido de Hidrogênio/metabolismo
18.
Res Vet Sci ; 159: 237-243, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37178627

RESUMO

Currently, beekeeping faces many risks, such as deteriorating health of honeybees in hives, which results in high mortality rates, mainly during winter. An important consequence is the emergence/re-emergence of communicable diseases such as varroosis or nosemosis. These diseases jeopardize the continuity of the sector because of the absence of effective treatments and harmful residues that they can be retained on wax or honey. This study aimed to evaluate how feed supplementation with probiotic and postbiotic products derived from lactic acid bacteria affected the strength, dynamic population, and sanitary parameters of honey bees. Three groups of 30 hives were established and fed with feed supplemented with control, probiotic, or postbiotic products, with a total of nine applications over two months in late spring. Two monitoring tests were conducted to evaluate the strength and health status of hives. Hives that consumed postbiotic products enhanced their strength, increased bee population and egg laying of the queen, and maintained their reserves of pollen, whereas these parameters decreased in hives belonging to other groups. Furthermore, although the results suggested a favorable effect of postbiotic products on the trend of N. ceranae infection levels, probiotics showed intermediate results. While awaiting long-term results regarding V. destructor infestation, which showed similar trends in all groups, feed supplementation with postbiotics could be an important tool for beekeepers to enhance the strength and health status of their hives.


Assuntos
Nosema , Probióticos , Urticária , Abelhas , Animais , Probióticos/farmacologia , Probióticos/uso terapêutico , Suplementos Nutricionais , Nível de Saúde , Urticária/veterinária
19.
Biomaterials ; 293: 121978, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36580719

RESUMO

The incorrect use of conventional drugs for both prevention and control of intestinal infections has contributed to a significant spread of bacterial resistance. In this way, studies that promote their replacement are a priority. In the last decade, the use of antimicrobial peptides (AMP), especially Ctx(Ile21)-Ha AMP, has gained strength, demonstrating efficient antimicrobial activity (AA) against pathogens, including multidrug-resistant bacteria. However, gastrointestinal degradation does not allow its direct oral application. In this research, double-coating systems using alginate microparticles loaded with Ctx(Ile21)-Ha peptide were designed, and in vitro release assays simulating the gastrointestinal tract were evaluated. Also, the AA against Salmonella spp. and Escherichia coli was examined. The results showed the physicochemical stability of Ctx(Ile21)-Ha peptide in the system and its potent antimicrobial activity. In addition, the combination of HPMCAS and chitosan as a gastric protection system can be promising for peptide carriers or other low pH-sensitive molecules, adequately released in the intestine. In conclusion, the coated systems employed in this study can improve the formulation of new foods or biopharmaceutical products for specific application against intestinal pathogens in animal production or, possibly, in the near future, in human health.


Assuntos
Anti-Infecciosos , Quitosana , Animais , Humanos , Quitosana/química , Alginatos/química , Peptídeos Antimicrobianos , Anti-Infecciosos/farmacologia
20.
Tree Physiol ; 42(9): 1720-1735, 2022 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-35285500

RESUMO

Understanding plant trait coordination and variance across climatic gradients is critical for assessing forests' adaptive potential to climate change. We measured 11 hydraulic, anatomical and leaf-level physiological traits in European beech (Fagus sylvatica L.) along a moisture and temperature gradient in the French Alps. We assessed how traits covaried, and how their population-level variances shifted along the gradient. The intrapopulation variances of vessel size and xylem-specific conductivity reduced in colder locations as narrow vessels were observed in response to low temperature. This decreased individual-level water transport capacity compared with the warmer and more xeric sites. Conversely, the maximum stomatal conductance and Huber value variances were constrained in the arid and warm locations, where trees showed restricted gas exchange and higher xylem-specific conductivity. The populations growing under drier and warmer conditions presented wide variance for the xylem anatomical and hydraulic traits. Our results suggest that short-term physiological acclimation to raising aridity and heat in southern beech populations may occur mainly at the leaf level. Furthermore, the wide variance of the xylem anatomical and hydraulic traits at these sites may be advantageous since more heterogeneous hydraulic conductivity could imply populations' greater tree-tree complementarity and resilience against climatic variability. Our study highlights that both intrapopulation trait variance and trait network analysis are key approaches for understanding species adaptation and the acclimation potential to a shifting environment.


Assuntos
Fagus , Temperatura Baixa , Fagus/fisiologia , Folhas de Planta/fisiologia , Árvores/fisiologia , Água , Xilema/fisiologia
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