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1.
Materials (Basel) ; 17(11)2024 Jun 04.
Article in English | MEDLINE | ID: mdl-38894006

ABSTRACT

This paper presents a method for designing low carbon bio-based building materials, also named bio-concretes, produced with wood wastes in shavings form (WS) and cementitious pastes. As the aggregates phase of bio-concretes is composed of plant-based particles, known as porous and high water-absorbing materials, the bio-concretes cannot be designed by using the traditional design rules used for conventional mortar or concrete. Then, the method used in the current paper is an adaptation of a previous one that has been developed in a recent paper where bio-concretes were produced with a cement matrix, three types of bio-aggregates, and a proposal of a design abacus. However, when that abacus is used for designing WBC with low cement content in the matrix, the target compressive strength is not reached. In the present paper, the method is extended to low cement content matrix (up to 70% of cement substitution) and also considering the greenhouse gas (GHG) emission of the WBC. To obtain data for proposing a new design abacus, an experimental program was carried out by producing nine workable WBCs, varying wood volumetric fractions (40-45-50%), and water-to-binder ratios. The bio-concretes produced presented adequate consistency, lightness (density between 715 and 1207 kg/m3), and compressive strength ranging from 0.64 to 12.27 MPa. In addition, the GHG emissions of the WBC were analysed through the Life Cycle Assessment methodology. From the relationships obtained between density, compressive strength, water-to-binder ratio, cement consumption, and GHG emissions of the WBC, calibration constants were proposed for developing the updated and more complete abacus regarding an integrated mix design methodology.

2.
Heliyon ; 10(10): e30723, 2024 May 30.
Article in English | MEDLINE | ID: mdl-38813200

ABSTRACT

Despite a growing body of evidence for the effectiveness of prehabilitation, the uptake of prehabilitation in Europe remains low. Contributing factors range from limited awareness and understanding of prehabilitation to a lack of supporting infrastructure and reimbursement challenges. In this position paper, the authors propose a new comprehensive definition of prehabilitation and identify differentiated thyroid cancer as a type of cancer particularly well-suited for prehabilitation. To support clinicians with the implementation of prehabilitation programs in their clinics, the authors discuss the following practical solutions: a) find the most appropriate prehabilitation program for each patient; b) raise awareness among peers; c) develop evidence to demonstrate the effectiveness of prehabilitation; d) expand the interdisciplinary team; e) expand your network and make use of existing assets; f) utilize learnings from the COVID-19 pandemic.

5.
Biomolecules ; 14(3)2024 Mar 20.
Article in English | MEDLINE | ID: mdl-38540797

ABSTRACT

Long-term potentiation (LTP) induced by theta-burst stimulation (TBS) undergoes postweaning developmental changes partially linked to GABAergic circuit maturation. Endogenous vasoactive intestinal peptide (VIP) acting on its VPAC1 receptor strongly influences LTP induced by theta-burst stimulation (TBS), an effect dependent on GABAergic transmission. Although VPAC1 receptor levels are developmentally regulated during embryogenesis, their variation along postweaning development is unknown, as is the VPAC1 modulation of LTP or its relation to hippocampal GABAergic circuit maturation. As such, we investigated how VPAC1 modulation of LTP adjusts from weaning to adulthood along with GABAergic circuit maturation. As described, LTP induced by mild TBS (5 bursts, 4 pulses delivered at 100 Hz) was increasingly greater from weaning to adulthood. The influence of the VPAC1 receptor antagonist PG 97-269 (100 nM) on TBS-induced LTP was much larger in juvenile (3-week-old) than in young adult (6-7-week-old) or adult (12-week-old) rats. This effect was not associated with a developmental decrease in synaptic VPAC1 receptor levels. However, an increase in pre and post-synaptic GABAergic synaptic markers suggests an increase in the number of GABAergic synaptic contacts that is more prominent than the one observed in glutamatergic connections during this period. Conversely, endogenous VPAC2 receptor activation did not significantly influence TBS-induced LTP. VPAC2 receptor levels enhance pronouncedly during postweaning development, but not at synaptic sites. Given the involvement of VIP interneurons in several aspects of hippocampal-dependent learning, neurodevelopmental disorders, and epilepsy, this could provide important insights into the role of VIP modulation of hippocampal synaptic plasticity during normal and altered brain development potentially contributing to epileptogenesis.


Subject(s)
Long-Term Potentiation , Transcranial Magnetic Stimulation , Rats , Animals , Long-Term Potentiation/physiology , Hippocampus , Neuronal Plasticity , Interneurons
6.
Braz J Microbiol ; 54(4): 2603-2607, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37702922

ABSTRACT

In this study, we investigate the ability of Pythium insidiosum to form biofilms across various substrates and the antibiofilm efficacy of 8-hydroxyquinoline derivatives (8-HQs). Biofilms of P. insidiosum were cultured on polystyrene plates, contact lenses, and horsehair. We provide the first evidence of P. insidiosum's biofilm-forming capability, thus considerably expanding our understanding of its transmission and pathogenesis. Our results demonstrate that 8-HQs effectively inhibit biofilm formation and eradicate pre-existing biofilms, underscoring their potential as a novel treatment strategy for pythiosis, a disease currently lacking a gold-standard treatment. This finding has particular relevance for ocular pythiosis associated with contact lens usage and potential infection sources in animals. Our results contribute to the scientific knowledge base and directly impact innovative therapeutic interventions' development.


Subject(s)
Pythiosis , Pythium , Animals , Antifungal Agents/pharmacology , Antifungal Agents/therapeutic use , Pythiosis/drug therapy , Pythiosis/microbiology
7.
Antioxidants (Basel) ; 12(2)2023 Feb 05.
Article in English | MEDLINE | ID: mdl-36829946

ABSTRACT

Chloroplast ascorbate peroxidases exert an important role in the maintenance of hydrogen peroxide levels in chloroplasts by using ascorbate as the specific electron donor. In this work, we performed a functional study of the stromal APX in rice (OsAPX7) and demonstrated that silencing of OsAPX7 did not impact plant growth, redox state, or photosynthesis parameters. Nevertheless, when subjected to drought stress, silenced plants (APX7i) show a higher capacity to maintain stomata aperture and photosynthesis performance, resulting in a higher tolerance when compared to non-transformed plants. RNA-seq analyses indicate that the silencing of OsAPX7 did not lead to changes in the global expression of genes related to reactive oxygen species metabolism. In addition, the drought-mediated induction of several genes related to the proteasome pathway and the down-regulation of genes related to nitrogen and carotenoid metabolism was impaired in APX7i plants. During drought stress, APX7i showed an up-regulation of genes encoding flavonoid and tyrosine metabolism enzymes and a down-regulation of genes related to phytohormones signal transduction and nicotinate and nicotinamide metabolism. Our results demonstrate that OsAPX7 might be involved in signaling transduction pathways related to drought stress response, contributing to the understanding of the physiological role of chloroplast APX isoforms in rice.

8.
Anal Methods ; 15(2): 154-163, 2023 01 06.
Article in English | MEDLINE | ID: mdl-36533314

ABSTRACT

This work investigated the potential of microwave-induced plasma optical emission spectrometry (MIP-OES) for urine analysis using a complex matrix containing carbon and high concentrations of easily ionizable elements (EIEs). The goals were to study interferences originating from the urine matrix for 14 analytes with total energies varying from 1.85 to 12.07 eV, along with strategies to correct matrix effects and compare the results with those reported in the literature using inductively coupled plasma optical emission spectrometry (ICP-OES). It was found that the urine matrix caused suppression of the signals for some elements and increased them for others. Therefore, an internal standardization calibration method and three levels of dilution, i.e., 2-, 20-, and 200-fold, were applied as strategies to correct non-spectral interferences. Also, Ga, Ge, Pd, Rh, Sc and Y and four molecular species present in the nitrogen plasma (i.e., CN, N2, N2+, and OH) were investigated as potential internal standards (ISs). The accuracy and precision were evaluated by addition and recovery experiments and best results were obtained using ISs Ge, Rh and Sc for 20-fold dilution and N2+ for 200-fold dilution. The LODs ranged from 0.33 to 329 µg L-1 and deviations were lower than 11%. The combined use of these strategies led to successful urine analysis for a spiked sample by MIP-OES.


Subject(s)
Spectrum Analysis , Limit of Detection
9.
PLoS One ; 17(12): e0272104, 2022.
Article in English | MEDLINE | ID: mdl-36516126

ABSTRACT

Amyotrophic lateral sclerosis (ALS) is characterized by the progressive degeneration of corticospinal tract motor neurons. Previous studies showed that adenosine-mediated neuromodulation is disturbed in ALS and that vascular endothelial growth factor (VEGF) has a neuroprotective function in ALS mouse models. We evaluated how adenosine (A1R and A2AR) and VEGF (VEGFA, VEGFB, VEGFR-1 and VEGFR-2) system markers are altered in the cortex and spinal cord of pre-symptomatic and symptomatic SOD1G93A mice. We then assessed if/how chronic treatment of SOD1G93A mice with a widely consumed adenosine receptor antagonist, caffeine, modulates VEGF system and/or the levels of Brain-derived Neurotrophic Factor (BDNF), known to be under control of A2AR. We found out decreases in A1R and increases in A2AR levels even before disease onset. Concerning the VEGF system, we detected increases of VEGFB and VEGFR-2 levels in the spinal cord at pre-symptomatic stage, which reverses at the symptomatic stage, and decreases of VEGFA levels in the cortex, in very late disease states. Chronic treatment with caffeine rescued cortical A1R levels in SOD1G93A mice, bringing them to control levels, while rendering VEGF signaling nearly unaffected. In contrast, BDNF levels were significantly affected in SOD1G93A mice treated with caffeine, being decreased in the cortex and increased in spinal the cord. Altogether, these findings suggest an early dysfunction of the adenosinergic system in ALS and highlights the possibility that the negative influence of caffeine previously reported in ALS animal models results from interference with BDNF rather than with the VEGF signaling molecules.


Subject(s)
Amyotrophic Lateral Sclerosis , Mice , Animals , Amyotrophic Lateral Sclerosis/drug therapy , Amyotrophic Lateral Sclerosis/genetics , Amyotrophic Lateral Sclerosis/metabolism , Brain-Derived Neurotrophic Factor/metabolism , Caffeine/pharmacology , Caffeine/metabolism , Vascular Endothelial Growth Factor A/metabolism , Vascular Endothelial Growth Factor Receptor-2/metabolism , Mice, Transgenic , Disease Models, Animal , Spinal Cord/metabolism , Receptors, Purinergic P1/genetics , Receptors, Purinergic P1/metabolism , Adenosine/metabolism , Superoxide Dismutase/genetics , Superoxide Dismutase/metabolism
10.
Materials (Basel) ; 15(23)2022 Nov 22.
Article in English | MEDLINE | ID: mdl-36499782

ABSTRACT

Experimental research on the direct shear behavior of fiber-reinforced concrete is often carried out using prisms molded with specific dimensions for a standardized test. However, the flow of fresh concrete in these molds can be different than in the case of a full-scale structural element. This is important considering that the flow direction highly influences the distribution and orientation of fibers. In addition, most of the studies did not relate their shear results to other mechanical properties. In contrast, this study attempted to deepen the experimental knowledge of the crack propagation of a steel fiber-reinforced concrete (SFRC) used in a full-scale prototype of a bridge box girder built in the laboratory. Prismatic specimens were sawn from webs and top flanges of this prototype. Serving as references, additional specimens were molded in wooden boxes. In a previous study of our research group, both had been tested under a three-point notched bending configuration maintaining test conditions proportional to the EN14651 specifications. From each of the previously flexurally tested specimens, two prismatic specimens suitable for the Fédération Internationale de la Précontrainte (FIP) shear test setup were extracted by adopting a cutting methodology that avoided the damage induced by the flexural tests to be part of the FIP specimens. These FIP specimens were tested in almost pure shear loading conditions for assessing the performance of SFRC. Computer tomography images and photos of the shear failure faces were used to determine the distribution and density of fibers. The results demonstrated that the peak loads were proportional to the fiber density at the shear failure section. Assuming that the SFRC conditions of the webs were representative of a common batching procedure in the construction industry, the results from the tests in specimens extracted from these webs were adopted to establish shear stress/flexural tensile stress ratios vs. crack mouth opening displacement curves. The curves belonging to cross-sections of a similar fiber density in the shear and flexural cases allowed for the proposal of a normalized crack-dilatancy relation composed of three stages of the crack propagation. In addition, a trilinear crack width-slip relation was established using the same set of specimens. The relevancy of this proposal is that the shear response can be estimated from a widely accepted standardized flexural test, which demands a simpler instrumentation and is also easier to execute than the shear setup.

11.
Rev Port Cardiol ; 41(8): 681-688, 2022 Aug.
Article in English, Portuguese | MEDLINE | ID: mdl-36073267

ABSTRACT

INTRODUCTION AND OBJECTIVES: Lifestyle changes are frequently insufficient to reduce cardiovascular (CV) risk in patients with dyslipidemia. This study aims to characterize the long-term evolution of lipid profile and CV risk of patients under primary prevention. METHODS: A retrospective study was performed of outpatients at a Portuguese cardiovascular risk clinic with ≥2 CV risk factors, followed for ≥2 years between 1995 and 2015. Statin therapy had been initiated early, in accordance with the clinic's practice. After written informed consent was obtained, sociodemographic and clinical characteristics were collected from medical charts, at baseline and last visit. Changes in lipid profile and CV risk scores were estimated. Associations between HDL-C or LDL-C changes and gender, age, observation time and treatments were assessed through bivariate analysis and multiple linear regression models. RESULTS: Out of 516 participants with mean follow-up of 11.4±4.3 years, 56.6% were female and 91.5% received statins. Lipid profile showed statistically significant improvement, including median changes in LDL-C and HDL-C of -77.0 mg/dl and +19 mg/dl, respectively. CV risk also showed statistically significant improvements according to all scores. Statin therapy resulted in a mean HDL-C increase of 7.4 mg/dl (independently of gender and other treatments) and a mean LDL-C reduction of 51.8 mg/dl (irrespective of age and other treatments). CONCLUSION: Results from this long-term real-life study indicate that primary prevention, specifically early and continuous therapy with intermediate-intensity statins as an add-on to lifestyle interventions, was important in obtaining consistent and adequate metabolic correction in patients with additional risk factors.

12.
Nutr. hosp ; 39(2): 305-312, mar.- abr. 2022. tab, graf
Article in English | IBECS | ID: ibc-209698

ABSTRACT

Background: reduced cognitive performance has been observed in patients with severe obesity. Bariatric surgery and subsequent adipose tissue loss seem to affect cognitive functioning positively; however, improvement predictors are not well established. Aim: to evaluate the cognitive performance and the nutritional status of patients with severe obesity 6-month after bariatric surgery. Methods: we assessed the neuropsychological performance of 22 patients with obesity (body mass index: ~ 42.9 kg/m²). The nutritional evaluation consisted of the routine tests performed in the baseline and postoperative periods. Lastly, we calculated the correlation between neuropsychological assessment results and blood biomarkers. Results: the patients did not present cognitive impairment in the preoperative assessment, but performed below the standard range. The patients underwent significant weight loss after 6 months from surgery (~ 22 kg), with a change in obesity class III to I. Also, the patients presented a significant improvement in attention, mental flexibility, inhibitory control, and processing speed. Additionally, we observed a significant improvement in serum folic acid (108 %), gamma-glutamyl transferase (-41 %), uric acid (-32 %), ferritin (-28 %), triglycerides (-19 %), and high-density lipoprotein (9 %). Lastly, we found a moderate positive correlation between processing speed and body weight (r = 0.46), gamma-glutamyl transferase (r = 0.54), and total protein and mental flexibility (r = 0.75). Conclusion: bariatric surgery promoted significant weight loss and improved attention, mental flexibility, processing speed, and several nutritional biomarkers. Nevertheless, the surgery had limited effects on other cognitive functions such as short- and long-term memory and language (AU)


Introducción: se ha observado una disminución del rendimiento cognitivo en los pacientes con obesidad grave. La cirugía bariátrica y la pérdida de tejido adiposo parecen mejorar el funcionamiento cognitivo; sin embargo, los predictores de mejora no están bien establecidos. Objetivos: evaluar el rendimiento cognitivo y el estado Nutricional de pacientes con obesidad severa después de 6 meses de una cirugía bariátrica. Métodos: evaluamos el desempeño neuropsicológico de 22 pacientes con un índice de masa corporal ~ 42,9 kg/m². Se analizaron las pruebas de rutina realizadas al inicio y después de la cirugía. Calculamos la correlación con la evaluación neuropsicológica y los biomarcadores sanguíneos. Resultados: los pacientes no mostraron deterioro cognitivo en la evaluación preoperatoria, pero sí un rendimiento por debajo del estándar. Los pacientes mostraron una pérdida de peso significativa 6 meses después de la cirugía (~ 22 kg), con un cambio de la clasificación de obesidad de III a I. Además, los pacientes mostraron una mejora significativa de la atención, la flexibilidad mental, el control inhibitorio y la velocidad de procesamiento. Además, observamos una mejora significativa del ácido fólico sérico (108 %), la gamma-glutamil-transferasa (-41 %), el ácido úrico (-32 %), la ferritina (-28 %), los triglicéridos (-19 %) y las lipoproteínas de alta densidad (9 %). Finalmente, encontramos una correlación positiva moderada entre la velocidad de procesamiento y el peso corporal (r = 0,46) y la gamma-glutamil-transferasa (r = 0,54), y entre la proteína total y la flexibilidad mental (r = 0,75). Conclusiones: la cirugía bariátrica promovió una pérdida de peso significativa y mejoró la atención, la flexibilidad mental, la velocidad de procesamiento y varios biomarcadores Nutricionales. Sin embargo, tuvo efectos limitados sobre otras funciones cognitivas, como la memoria y el lenguaje a corto y largo plazo (AU)


Subject(s)
Humans , Male , Female , Young Adult , Adult , Middle Aged , Bariatric Surgery/methods , Obesity, Morbid/psychology , Obesity, Morbid/surgery , Cognition , Prospective Studies , Longitudinal Studies , Body Mass Index , Weight Loss , Pilot Projects , Neuropsychological Tests
13.
J Org Chem ; 87(12): 7610-7617, 2022 06 17.
Article in English | MEDLINE | ID: mdl-35171607

ABSTRACT

Ellipticine was synthesized in six steps and 20% global yield starting from the readily available 2,5-dimethoxy isoquinoline. Unprecedented regioselective control of the nucleophilic attack on the isoquinoline-5,8-dione is first described. Investigation of the possible pathways of this transformation through density functional theory calculations reveals unexpected N-oxide assistance in cascade tautomerizations, which was crucial for directing the nucleophilic attack and hastening the overall process. Using this strategy, we prepared the aniline-isoquinolinedione adduct and submitted it to an intramolecular double C-H cross-coupling activation to furnish ellipticinequinone, which gave ellipticine after a MeLi addition/BH3 reduction sequence.


Subject(s)
Ellipticines , Isoquinolines
14.
Lett Appl Microbiol ; 74(3): 395-404, 2022 Mar.
Article in English | MEDLINE | ID: mdl-34822194

ABSTRACT

Often associated to the colonization by Candida spp. biofilm, the catheter-related infections are a serious health problem since the absence of a specific therapy. Hence, the main objective of this work was to evaluate the activity of 8-hydroxyquinoline and quinazoline derivatives on Candida spp. biofilms. A quinazoline derivative (PH100) and an 8-hydroxyquinoline derivative (PH157) were tested against nine strains of C. albicans, C. tropicalis and C. parapsilosis, and their biofilms in polystyrene microtitre plates and on polyurethane central venous catheter. The PH157 compound was incorporated into a film-forming system-type formulation and its capacity to inhibit biofilm formation on catheters was evaluated. The compounds were active against planktonic and sessile cells, as well as against the tested biofilms. PH157 compound performed better than the PH100 compound. The formulation containing PH157 presented results very similar to those of the compound in solution, which indicates that its activity was preserved. Both compounds showed activity against Candida spp. strains and their biofilm, with better PH157 activity. The formulation preserved the action of the PH157 compound, in addition, it facilitates its application on the catheter. The structural modifications that these compounds allow can generate compounds that are even more active, both against planktonic cells and biofilms.


Subject(s)
Candida , Oxyquinoline , Antifungal Agents/pharmacology , Antifungal Agents/therapeutic use , Biofilms , Microbial Sensitivity Tests , Quinazolines
15.
J Appl Microbiol ; 2022 Dec 14.
Article in English | MEDLINE | ID: mdl-36626733

ABSTRACT

AIMS: To evaluate the antimicrobial activity and to determine the pharmacodynamic characteristics of three 8-hydroxyquinoline derivatives (8-HQs) against Pythium insidiosum, the causative agent of pythiosis. METHODS AND RESULTS: Antimicrobial activity was tested by broth microdilution and MTT assays. The antimicrobial mode of action was investigated using sorbitol protection assay, ergosterol binding assay, and scanning electron microscopy. Clioquinol, PH151, and PH153 were active against all isolates, with MIC values ranging from 0.25 to 2 µg ml-1. They also showed a time- and dose-dependent antimicrobial effect, damaging the P. insidiosum cell wall. CONCLUSIONS: Together, these results reinforce the potential of 8-HQs for developing new drugs to treat pythiosis.

16.
Anal Methods ; 13(46): 5670-5678, 2021 12 02.
Article in English | MEDLINE | ID: mdl-34792519

ABSTRACT

A simple, sensitive and matrix-effect free analytical method for simultaneous determination of Cd, Hg and Pb in drug samples (i.e., commercial dosage tablets) by inductively coupled plasma optical emission spectrometry (ICP OES) has been developed. According to the United States Pharmacopeia (USP) Chapter 232, those metals are considered elemental impurities from class 1 and they must be assessed in pharmaceutical production as well as in quality control evaluation. In order to increase the sensitivity of the analysis, dispersive liquid-liquid microextraction (DLLME) was performed and seven factors affecting analyte extraction were optimized by multivariate analysis. A microvolume of analyte enriched phase was directly introduced into the plasma using a multi-nebulizer, providing a high enrichment factor. When compared to conventional ICP OES analysis, DLLME improves the limit of quantitation (LOQ) values on average 40-fold for all analytes. Consequently, LOQ values were significantly lower than their permissible daily exposure limits for oral drugs. Accuracy was evaluated by addition and recovery experiments following USP recommendations in eight commercial drug samples. Recovery and RSD values were within the range of 90-108% and 1-9%, respectively.


Subject(s)
Liquid Phase Microextraction , Mercury , Cadmium , Lead , Spectrum Analysis , United States
17.
Anal Chim Acta ; 1185: 339052, 2021 Nov 15.
Article in English | MEDLINE | ID: mdl-34711330

ABSTRACT

A simple, fast, sensitive and green pretreatment method for determination of Cd, Co, Hg, Ni, Pb and V in oral and parenteral drug samples using inductively coupled plasma optical emission spectrometry (ICP OES) has been developed. According to United States Pharmacopoeia (USP), those metals must be reported in all pharmaceutical products for quality control evaluation (i.e., elemental impurities from classes 1 and 2A of USP Chapter 232). To improve the analytical capabilities of ICP OES, a dispersive liquid-liquid microextraction (DLLME) has performed using a safe, cheap and biodegradable deep eutectic solvent (DES) as extractant solvent (a mixture of 2:1 M ratio of DL-menthol and decanoic acid). Seven parameters affecting the microextraction efficiency have carefully optimized by multivariate analysis. Under optimized conditions, the DES-based DLLME-ICP OES procedure improved limit of quantitation (LOQ) values on range from 12 to 85-fold and afforded an enrichment factor on average 60-times higher than those obtained to direct ICP OES analysis. Consequently, LOQ values for Cd, Co, Hg, Ni, Pb and V have been on average 10-times lower than target limits recommended for drugs from parenteral route of administration. Trueness has evaluated by addition and recovery experiments following USP recommendations for three oral drug samples in liquid dosage form and three parenteral drugs. Recovery and RSD values have been within the range of 90-109% and 1-6%, respectively. All analytes were below the respectives LOQ values, hence, lower than the limits proposed by USP Chapter 232.


Subject(s)
Liquid Phase Microextraction , Pharmaceutical Preparations , Limit of Detection , Solvents , Spectrum Analysis
18.
Environ Pollut ; 286: 117239, 2021 Oct 01.
Article in English | MEDLINE | ID: mdl-33990048

ABSTRACT

Several environmental pollutants, including pesticides, herbicides and persistent organic pollutants play an important role in the development of chronic diseases. However, most studies have examined environmental pollutants toxicity in target organisms or using a specific toxicological test, losing the real effect throughout the ecosystem. In this sense an integrative environmental risk of pollutants assessment, using different model organisms is necessary to predict the real impact in the ecosystem and implications for target and non-target organisms. The objective of this study was to use alachlor, a chloroacetanilide herbicide responsible for chronic toxicity, to understand its impact in target and non-target organisms and at different levels of biological organization by using several model organisms, including membranes of dipalmitoylphosphatidylcholine (DPPC), rat liver mitochondria, bacterial (Bacillus stearothermophilus), plant (Lemna gibba) and mammalian cell lines (HeLa and neuro2a). Our results demonstrated that alachlor strongly interacted with membranes of DPPC and interfered with mitochondrial bioenergetics by reducing the respiratory control ratio and the transmembrane potential. Moreover, alachlor also decreased the growth of B. stearothermophilus and its respiratory activity, as well as decreased the viability of both mammalian cell lines. The values of TC50 increased in the following order: Lemna gibba < neuro2a < HeLa cells < Bacillus stearothermophilus. Together, the results suggest that biological membranes constitute a putative target for the toxic action of this lipophilic herbicide and point out the risks of its dissemination on environment, compromising ecosystem equilibrium and human health.


Subject(s)
Environmental Pollutants , Herbicides , Water Pollutants, Chemical , Acetamides , Animals , Ecosystem , Environmental Pollutants/toxicity , HeLa Cells , Herbicides/toxicity , Humans , Rats , Risk Assessment
19.
Theor Exp Plant Physiol ; 33(2): 113-124, 2021.
Article in English | MEDLINE | ID: mdl-33842196

ABSTRACT

In October 2020, at the peak of the COVID-19 pandemic, a group of young Brazilian photosynthesis researchers organized the 1st Brazilian Symposium on Photosynthesis. The event was free and online, with the presence of important guest speakers from all over the world, who discussed their recent works on topics related to the future and perspectives of photosynthesis research. Summarizing the expectations of this symposium we highlighted the importance of adopting a systemic perspective for a better understanding of photosynthesis as a complex and dynamic process. Plants are modular and self-regulating presenting metabolic redundancy and functional degeneration. Among the various biological processes, photosynthesis plays a crucial role in promoting the direct conversion of light energy into carbon skeletons for support growth and productivity. In the past decades, significant advances have been made in photosynthesis at the biophysical, biochemical, and molecular levels. However, this myriad of knowledge has been insufficient to answer crucial questions, such as: how can we understand and eventually increase photosynthetic efficiency and yield in crops subjected to adverse environment related to climate-changing? We believe that a crucial limitation to the whole comprehension of photosynthesis is associated with a vastly widespread classic reductionist view. Moreover, this perspective is commonly accompanied by non-integrative, simplistic, and descriptive approaches to investigate a complex and dynamic process as photosynthesis. Herein, we propose the use of new approaches, mostly based on the Systems Theory, which certainly comes closer to the real world, such as the complex systems that the plants represent.

20.
J Appl Microbiol ; 131(3): 1440-1451, 2021 Sep.
Article in English | MEDLINE | ID: mdl-33565222

ABSTRACT

AIM: The purpose of this study was to evaluate the in vitro and in vivo efficiency of derivatives of 8-Hydroxyquinoline (8HQ) in controlling the fungus Ilyonectria liriodendri. METHODS AND RESULTS: The in vitro tests consisted of assessing its susceptibility to the minimal inhibitory concentration (MIC) and the inhibition of mycelial growth. While the in vivo tests consisted of applying and assessing the most effective products for the protection of wounds, in both preventive + curative and curative forms. The MIC values for PH 151 (6·25 µg ml-1 ) showed better results when compared to the fungicides tebuconazole (>50 µg ml-1 ) and mancozeb (12·5 µg ml-1 for strain 176 and 25 µg ml-1 for strain 1117). PH 151 significantly inhibited mycelial growth, while mancozeb did not differ from the control. In in vivo tests, PH 151 again demonstrated excellent results in vitro, especially when applied preventively. CONCLUSIONS: The derivative of 8HQ PH 151 was effective in controlling the fungus I. liriodendri in vitro and proved to be a promising option for protecting wounds. SIGNIFICANCE AND IMPACT OF THE STUDY: This study points to the prospect of an effective and safe preventive antifungal product, which would enable the use of pesticides in vine culture to be reduced.


Subject(s)
Fungicides, Industrial/pharmacology , Hypocreales , Oxyquinoline , Plant Diseases , Vitis/microbiology , Hypocreales/pathogenicity , Microbial Sensitivity Tests , Oxyquinoline/pharmacology , Plant Diseases/microbiology , Plant Diseases/prevention & control
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