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1.
Water Sci Technol ; 89(8): 2105-2117, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38678412

RESUMEN

Photodynamic processes have found widespread application in therapies. These processes involve photosensitizers (PSs) that, when excited by specific light wavelengths and in the presence of molecular oxygen, generate reactive oxygen species (ROS), that target cells leading to inactivation. Photodynamic action has gained notable attention in environmental applications, particularly against pathogens and antibiotic-resistant bacteria (ARB) that pose a significant challenge to public health. However, environmental matrices frequently encompass additional contaminants and interferents, including microplastics (MPs), which are pollutants of current concern. Their presence in water and effluents has been extensively documented, highlighting their impact on conventional treatment methods, but this information remains scarce in the context of photodynamic inactivation (PDI) setups. Here, we described the effects of polyvinyl chloride (PVC) microparticles in PDI targeting Staphylococcus aureus and its methicillin-resistant strain (MRSA), using curcumin as a PS under blue light. The presence of PVC microparticles does not hinder ROS formation; however, depending on its concentration, it can impact bacterial inactivation. Our results underscore that PDI remains a potent method for reducing bacterial concentrations in water and wastewater containing ARB, even in highly contaminated scenarios with MPs.


Asunto(s)
Staphylococcus aureus Resistente a Meticilina , Microplásticos , Cloruro de Polivinilo , Staphylococcus aureus , Cloruro de Polivinilo/química , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Staphylococcus aureus Resistente a Meticilina/efectos de la radiación , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/efectos de la radiación , Especies Reactivas de Oxígeno/metabolismo , Fármacos Fotosensibilizantes/farmacología , Fármacos Fotosensibilizantes/química
2.
Sensors (Basel) ; 23(18)2023 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-37765728

RESUMEN

Indoor agriculture is emerging as a promising approach for increasing the efficiency and sustainability of agri-food production processes. It is currently evolving from a small-scale horticultural practice to a large-scale industry as a response to the increasing demand. This led to the appearance of plant factories where agri-food production is automated and continuous and the plant environment is fully controlled. While plant factories improve the productivity and sustainability of the process, they suffer from high energy consumption and the difficulty of providing the ideal environment for plants. As a small step to address these limitations, in this article we propose to use internet of things (IoT) technologies and automatic control algorithms to construct an energy-efficient remote control architecture for grow lights monitoring in indoor farming. The proposed architecture consists of using a master-slave device configuration in which the slave devices are used to control the local light conditions in growth chambers while the master device is used to monitor the plant factory through wireless communication with the slave devices. The devices all together make a 6LoWPAN network in which the RPL protocol is used to manage data transfer. This allows for the precise and centralized control of the growth conditions and the real-time monitoring of plants. The proposed control architecture can be associated with a decision support system to improve yields and quality at low costs. The developed method is evaluated in emulation software (Contiki-NG v4.7),its scalability to the case of large-scale production facilities is tested, and the obtained results are presented and discussed. The proposed approach is promising in dealing with control, cost, and scalability issues and can contribute to making smart indoor agriculture more effective and sustainable.

3.
J Phys Chem A ; 126(43): 7852-7863, 2022 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-36282217

RESUMEN

The structural and electronic properties of 2,3-dimethoxybenzaldehyde (2,3-DMB), 5-bromo-2,3-dimethoxybenzaldehyde (5-BRB), and 6-bromo-2,3-dimethoxybenzaldehyde (6-BRB) were extensively discussed with emphasis on linear and nonlinear optical responses. The intermolecular interactions were comparatively studied by Hirshfeld surfaces, quantum theory of atoms in molecules (QTAIM), and natural bond orbitals (NBOs), indicating that bromine substitution decreases the H···H and C···H contacts and increases H···Br and Br···Br closed-shell interactions on crystalline arrangements. The frontier molecular orbitals and molecular electrostatic potential map, carried out at the CAM-B3LYP/6-311++G(d,p) level of theory, showed that the kinetic stability occurs in the increasing order 6-BRB < 5-BRB < 2.3-DMB. The bromine atom has a beneficial effect on the nonlinear third-order susceptibility of 2,3-DMB, with theoretical predictions of 89.54 ×10-22 and 83.15 ×10-22 (m/V)2 for 6-BRB and 5-BRB, respectively. These findings were favorably compared with available theoretical and experimental data of other organic crystals that may be promising as NLO materials.

4.
Pharmacology ; 107(3-4): 167-178, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35100605

RESUMEN

INTRODUCTION: Hydrocarbons with sufficient water solubility allosterically modulate anesthetic-sensitive ion channels. Mint extracts L-carvone and methyl salicylate water solubility exceeds modulation cutoff values for γ-amino butyric acid type A (GABAA) receptors, N-methyl-D-aspartate (NMDA) receptors, and type-2 voltage-gated sodium (Nav1.2) channels. We hypothesized that mint extracts modulate these channels at concentrations that anesthetize rats. METHODS: Channels were expressed separately in frog oocytes and studied using 2-electrode voltage clamp techniques at drug concentrations up to 10 mM. Normalized current effects were fit to Hill equations. Mint compounds were formulated in a lipid emulsion and administered IV to rats. When unresponsive to the tail clamp, rats were exsanguinated, and plasma drug concentrations were measured. RESULTS: Both mint compounds caused concentration-dependent inhibition of all channels except for methyl salicylate which inhibited GABAA receptors at low concentrations and potentiated at high concentrations. Plasma drug concentrations in anesthetized rats were 7.9 mM for L-carvone and 2.7 mM for methyl salicylate. This corresponded to ≥53% NMDA receptor inhibition and ≥78% Nav1.2 channel inhibition by both compounds and 30% potentiation of GABAA receptors by methyl salicylate. CONCLUSION: L-Carvone and methyl salicylate allosterically modulate cell receptor targets important to molecular actions of conventional anesthetics at concentrations that also induce general anesthesia in rats.


Asunto(s)
Anestésicos , Mentha , Anestésicos/farmacología , Animales , Monoterpenos Ciclohexánicos , Oocitos , Extractos Vegetales/farmacología , Ratas , Receptores de GABA-A/fisiología , Receptores de N-Metil-D-Aspartato , Salicilatos , Xenopus laevis
5.
Molecules ; 27(22)2022 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-36432059

RESUMEN

Angiotensin-converting enzyme (ACE) inhibitors are one of the most active classes for cardiovascular diseases and hypertension treatment. In this regard, developing active and non-toxic ACE inhibitors is still a continuous challenge. Furthermore, the literature survey shows that oxidative stress plays a significant role in the development of hypertension. Herein, glutathione's molecular structure and supramolecular arrangements are evaluated as a potential ACE inhibitor. The tripeptide molecular modeling by density functional theory, the electronic structure by the frontier molecular orbitals, and the molecular electrostatic potential map to understand the biochemical processes inside the cell were analyzed. The supramolecular arrangements were studied by Hirshfeld surfaces, quantum theory of atoms in molecules, and natural bond orbital analyses. They showed distinct patterns of intermolecular interactions in each polymorph, as well as distinct stabilizations of these. Additionally, the molecular docking study presented the interactions between the active site residues of the ACE and glutathione via seven hydrogen bonds. The pharmacophore design indicated that the hydrogen bond acceptors are necessary for the interaction of this ligand with the binding site. The results provide useful information for the development of GSH analogs with higher ACE inhibitor activity.


Asunto(s)
Inhibidores de la Enzima Convertidora de Angiotensina , Hipertensión , Humanos , Inhibidores de la Enzima Convertidora de Angiotensina/farmacología , Inhibidores de la Enzima Convertidora de Angiotensina/química , Simulación del Acoplamiento Molecular , Sitios de Unión , Glutatión
6.
Am J Bot ; 108(5): 828-843, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-34019302

RESUMEN

PREMISE: There is little direct evidence linking floral development and pollination biology in plants. We characterize both aspects in plain and ornamented flowers of Trimezieae (Iridaceae) to investigate how changes in floral ontogeny may affect their interactions with pollinators through time. METHODS: We examined floral ontogeny in 11 species and documented pollination biology in five species displaying a wide range of floral morphologies. We coded and reconstructed ancestral states of flower types over the tribal phylogeny to estimate the frequency of transition between different floral types. RESULTS: All Trimezieae flowers are similar in early floral development, but ornamented flowers have additional ontogenetic steps compared with plain flowers, indicating heterochrony. Ornamented flowers have a hinge pollination mechanism (newly described here) and attract more pollinator guilds, while plain flowers offer less variety of resources for a shorter time. Although the ornamented condition is plesiomorphic in this clade, shifts to plain flowers have occurred frequently and abruptly during the past 5 million years, with some subsequent reversals. CONCLUSIONS: Heterochrony has resulted in labile morphological changes during flower evolution in Trimezieae. Counterintuitively, species with plain flowers, which are endemic to the campo rupestre, are derived within the tribe and show a higher specialization than the ornamented species, with the former being visited by pollen-collecting bees only.


Asunto(s)
Iridaceae , Polinización , Animales , Abejas , Biología , Flores , Polen
7.
Vet Anaesth Analg ; 48(4): 585-595, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33934992

RESUMEN

OBJECTIVE: To determine the pharmacokinetics and pharmacodynamics of high-concentration formulation of buprenorphine (1.8 mg mL-1; Simbadol) following subcutaneous (SC) administration in horses. STUDY DESIGN: Prospective, randomized, crossover trial. ANIMALS: A group of six healthy adult horses weighing 521-602 kg. METHODS: On three occasions, Simbadol (0.005 mg kg-1; treatment S5), (0.0025 mg kg-1; treatment S2.5) or saline (treatment SAL) were administered SC at least 7 days apart in random order. Electrical nociceptive threshold (ENT) measured on the neck region, physiologic variables, locomotor activity, degree of restlessness and presence of excitatory signs were measured at baseline and for up to 48 hours after injection. Blood was collected for pharmacokinetic analysis at the same time intervals and plasma buprenorphine concentration (Cp) measured using liquid chromatography-tandem mass spectrometry. RESULTS: Buprenorphine was quantifiable in all horses from 15 minutes after administration up to 8-12 hours. ENT was significantly increased in treatment S2.5 compared with treatment SAL at 0.75-6 hours after treatment. Increase in locomotor activity and compulsive behavior were recorded in all horses after Simbadol, and degree of restlessness was significantly higher in treatment S5 than SAL for a sustained time. Gastrointestinal motility significantly decreased in all horses after Simbadol and returned to baseline by 16 hours after treatment. CONCLUSIONS AND CLINICAL RELEVANCE: In horses, SC Simbadol was rapidly absorbed and Cp decreased rapidly. Side effects commonly seen in horses after opioids were observed in both Simbadol treatments, but degree of opioid-induced excitement lasted significantly longer in treatment S5. Simbadol (0.0025 mg kg-1) SC has the potential to be used clinically to treat pain in horses. However, at this dose, duration of antinociceptive effects was not longer than that reported for conventional buprenorphine, and side effects, including reduction in gastrointestinal motility and increased locomotor activity, were documented.


Asunto(s)
Buprenorfina , Analgésicos Opioides/farmacología , Animales , Buprenorfina/farmacología , Caballos , Dolor/veterinaria , Dimensión del Dolor , Estudios Prospectivos
8.
Mol Phylogenet Evol ; 143: 106692, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31770589

RESUMEN

Worldwide distributed tropical savannas were established only in the Miocene, with climatic cooling and rise of C4 grasses. However, there is evidence for an earlier presence of savanna-like vegetation in southern parts of South America. Here we investigated the biogeographic history of a clade of solitary bees which have endemic groups in areas covered by savannas and other types of open vegetation as well as forested areas. We hypothesized that these bees originated in savanna-like biomes and that shifts to forested areas and floral host shifts increased species diversification along their evolutionary history. We reconstructed a comprehensive phylogeny for Tapinotaspidini bees based majorly on original DNA sequences. We then used macroevolutionary tools to estimate ancestral range area and reconstructed ancestral habitat (open versus forested) and host plant association to analyze the effects of shifts in vegetation type and flower hosts on their diversification. Tapinotaspidini bees originated in the Paleocene and in a savanna-type, Cerrado-like, which is reinforced by reconstruction of open vegetation as the most probable ancestral area, thus bringing additional evidence to a much earlier origin of this vegetation type in South America. Shifts to forested areas occurred at least three times in a period of 30 Ma and were responsible for slight increases in diversification rates. Malpighiaceae is the ancestral floral host; host broadening occurred only in the Miocene and at least in three occasions. Host shifts, i.e. from Malpighiaceae to other oil families, occurred in the Eocene and Miocene. Both host broadening and host shifts did not significantly alter diversification rates, however exploitation of other oil sources were important in occupying new habitats. The link between biomes and host plant shifts and changes in diversification rate brings us additional insights into the evolution of bees and associated flora in South America.


Asunto(s)
Abejas/clasificación , Animales , Abejas/genética , Abejas/fisiología , Evolución Biológica , Complejo IV de Transporte de Electrones/clasificación , Complejo IV de Transporte de Electrones/genética , Fósiles/historia , Pradera , Historia Antigua , Malpighiaceae/crecimiento & desarrollo , Malpighiaceae/fisiología , Filogenia , Filogeografía , América del Sur
9.
Toxicol Mech Methods ; 30(7): 536-545, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32544017

RESUMEN

Coffee is the most popular hot beverage and caffeine is the most used psychoactive drug in the world. Roasting of coffee beans leads to the generation of minute quantities of undesirable compounds, such as furan. It is now thought that the toxicity of furan derives from its processing by CYP450 family of detoxifying enzymes, leading to the formation of cis-2-butene-1,4-dial (BDA). BDA has known cytotoxicity capacities, binding to proteins, nucleic acids, and glutathione (GSH). BDA also appears to mediate furan's toxic effects, since the inhibition of CYP450 family impedes the aforementioned toxicological effects of furan. There are some studies performed on furan's toxicity, but very few on BDA. Furthermore, the doses used in these studies appear to be fairly high when compared with the expected dosage one could be exposed to in a standard day. As such, to understand if furan and BDA could have toxic effects using more realistic doses and longer time frames, human and rat hepatocytes were exposed to furan or BDA for up to 96 h, and several biochemical parameters were assessed. We report here that human hepatocytes were more sensitive than rat's, in particular to furan, for we show a decrease in MTT reduction, ATP levels and increase in carbonyl formation and 8-OHdG accumulation in the longer time points. BDA was mostly ineffective, which we attribute to a low import rate into the cells. In conclusion, we show that there is potential for harm from furan in high doses, which should be carefully addressed.


Asunto(s)
Aldehídos/toxicidad , Café/toxicidad , Furanos/toxicidad , Hepatocitos/efectos de los fármacos , Semillas/toxicidad , 8-Hidroxi-2'-Desoxicoguanosina/metabolismo , Adenosina Trifosfato/metabolismo , Animales , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Culinaria , Daño del ADN , Relación Dosis-Respuesta a Droga , Hepatocitos/metabolismo , Hepatocitos/patología , Calor , Humanos , Estrés Oxidativo/efectos de los fármacos , Carbamilación de Proteína/efectos de los fármacos , Ratas , Especificidad de la Especie , Factores de Tiempo
10.
Reprod Domest Anim ; 54(12): 1567-1573, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31520567

RESUMEN

This study aims to investigate the effect of melatonin on activation, growth and morphology of bovine primordial follicles, as well as on stromal cells density in ovarian tissues after in vitro culture. Ovarian fragments were cultured in α-MEM+ alone or supplemented with melatonin (250, 500, 1,000 or 2,000 pM) for a period of six days. Non-cultured and cultured tissues were processed for histological analysis; according to developmental stages, follicles were classified as primordial or growing follicles. These follicles were further classified as morphologically normal or degenerated. Ovarian stromal cell density was also evaluated. The percentages of primordial and developing follicles, as well as those classified of normal follicles, were compared by Fisher's exact test, and the differences were considered significant when p < .05. The results showed that the presence of 1,000 and 2,000 pM melatonin in culture medium promoted a reduction in the percentage of primordial follicles and an increase in the percentage of development follicles, when compared to follicles cultured in control medium. On the other hand, the presence of 250 or 500 pM melatonin did not show a significant effect on the percentage of primordial and developing follicles. Besides that, the presence of 500, 1,000 and 2,000 pM melatonin maintained the percentage of normal follicles similar to those seen uncultured control. Moreover, tissues cultured in presence of 1,000 pM melatonin showed a higher percentage of normal follicles when compared to follicles cultured in the presence of 250 pM melatonin. It was observed a similar profile of stromal density in both uncultured tissues and those cultured in vitro in the presence of melatonin. In conclusion, melatonin (1,000 and 2,000 pM) promotes bovine primordial follicles activation and maintains the stromal cell density during in vitro culture of ovarian cortical tissue.


Asunto(s)
Antioxidantes/farmacología , Melatonina/farmacología , Folículo Ovárico/efectos de los fármacos , Folículo Ovárico/crecimiento & desarrollo , Técnicas de Cultivo de Tejidos/veterinaria , Animales , Bovinos , Femenino
11.
Can Vet J ; 58(11): 1191-1194, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-29089657

RESUMEN

The requirement for post-operative analgesia after ovariohysterectomy (OH) versus orchiectomy in dogs and cats was compared. Twelve male and 12 female cats and 12 male and 12 female dogs received meloxicam, 0.1 mg/kg body weight, PO, 2 h before surgery. Eleven female cats and 3 female dogs received rescue analgesia (P = 0.002). No male of either species required rescue analgesia. The number of cats receiving rescue analgesia was greater in females than in males (P < 0.0001). One should not rely solely on preoperative short-acting opioid and preemptive use of NSAIDs to control postoperative pain following OH, in dogs or cats. Postoperative pain after OH should be assessed for at least 2 h for cats and 4 h for dogs, using species-specific validated tools, to ensure proper postoperative pain diagnosis and management. Male dogs and cats subjected to orchiectomy required less postoperative analgesia intervention than female dogs and cats submitted to OH.


L'ovariohystérectomie nécessite d'avantage d'antalgiques post-opératoires que l'orchiectomie chez les chiens et les chats. Dans cette étude, nous avons comparé le besoin en antalgiques post-opératoires après l'OH versus l'orchiectomie chez les chiens et les chats. Douze mâles et 12 femelles, chats et chiens, ont reçu 0,1 mg/kg de Méloxicam par voie orale, 2h avant chirurgie. Onze chattes et trois chiennes ont eu besoin d'antalgiques de secours (P = 0,002). Aucun mâle de l'une ou l'autre espèce n'en a eu besoin. Chez les chats, les besoins en antalgiques de secours étaient plus élevés chez les femelles que les mâles (P < 0,0001). Il est donc primordial de ne pas se fier uniquement aux opioïdes à action courte préopératoire, et à l'utilisation préventive des AINS, pour contrôler la douleur post-opératoire après OH, tant chez le chien que chez le chat. L'évaluation de la douleur post-opératoire après l'OH devrait être suivie pendant au moins 2 heures pour les chats, et 4 heures pour les chiens, en utilisant des outils validés et spécifiques pour chaque espèce, afin d'assurer un diagnostic et une prise en charge post-opératoire appropriés à la douleur. Chez les chiens et les chats, les mâles soumis à l'orchiectomie ont nécessité moins d'intervention d'antalgiques post-opératoires que les femelles soumissent à l'OH.(Traduit par les auteurs).


Asunto(s)
Analgésicos no Narcóticos/uso terapéutico , Gatos/fisiología , Perros/fisiología , Histerectomía/veterinaria , Orquiectomía/veterinaria , Ovariectomía/veterinaria , Dolor Postoperatorio/veterinaria , Analgésicos no Narcóticos/administración & dosificación , Animales , Gatos/cirugía , Perros/cirugía , Femenino , Masculino , Dolor Postoperatorio/prevención & control
12.
Org Biomol Chem ; 13(26): 7131-5, 2015 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-26052965

RESUMEN

The microwave-assisted catalytic hydrogenation of the isoxazolidine-fused meso-tetrakis(pentafluorophenyl)chlorin afforded directly a mono-annulated chlorin with a singular 1-methyl-2,3-dihydro-1H-benzo[b]azepine ring that resulted from the cleavage of the isoxazolidine N-O bond followed by an intramolecular nucleophilic aromatic substitution of an o-F atom. The subsequent treatment of the mono-annulated chlorin with NaH induced a second intramolecular nucleophilic aromatic substitution, generating a bis-annulated chlorin having an additional 2H-pyran ring.

13.
J Insect Sci ; 14: 49, 2014 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-25373196

RESUMEN

Two species of stick insects are currently known to be present in the Macaronesian archipelagos: Clonopsis gallica (Charpentier) (Phasmatodea: Bacillidae) on the Canary Islands and in the Azores and Carausius morosus (Sinéty) (Phasmatidae) in the Azores. Here, we provide the first reliable records of the presence and distribution of C. gallica and C. morosus on Madeira Island. Egg and adult stages are briefly described along with some notes on the life history of these species in captivity. Data on islandwide distribution are based on specimens donated by the public in response to an article published in a daily newspaper. This method of data collection raised great popular interest in stick insects. The role of newspapers as a means of communicating awareness in biodiversity issues is discussed.


Asunto(s)
Distribución Animal , Biodiversidad , Insectos/fisiología , Animales , Femenino , Insectos/anatomía & histología , Insectos/crecimiento & desarrollo , Óvulo/fisiología , Portugal
14.
Zootaxa ; 5404(1): 76-101, 2024 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-38480406

RESUMEN

Three new species of Tetrapedia Klug, 1810 (Apidae) from Central Brazil are described and illustrated: Tetrapedia marina sp. nov., Tetrapedia tereza sp. nov., and Tetrapedia bruno sp. nov. Additionally, a key to the 22 species of Tetrapedia known from Brazil is provided. The lectotype of T. clypeata Friese is designated to establish the species name.


Asunto(s)
Himenópteros , Abejas , Animales , Brasil , Distribución Animal
15.
Environ Sci Pollut Res Int ; 31(12): 18281-18295, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37837598

RESUMEN

Recently, the increasing prevalence of solar energy in power and energy systems around the world has dramatically increased the importance of accurately predicting solar irradiance. However, the lack of access to data in many regions and the privacy concerns that can arise when collecting and transmitting data from distributed points to a central server pose challenges to current predictive techniques. This study proposes a global solar radiation forecasting approach based on federated learning (FL) and convolutional neural network (CNN). In addition to maintaining input data privacy, the proposed procedure can also be used as a global supermodel. In this paper, data related to eight regions of Iran with different climatic features are considered as CNN input for network training in each client. To test the effectiveness of the global supermodel, data related to three new regions of Iran named Abadeh, Jarqavieh, and Arak are used. It can be seen that the global forecasting supermodel was able to forecast solar radiation for Abadeh, Jarqavieh, and Arak regions with 95%, 92%, and 90% accuracy coefficients, respectively. Finally, in a comparative scenario, various conventional machine learning and deep learning models are employed to forecast solar radiation in each of the study regions. The results of the above approaches are compared and evaluated with the results of the proposed FL-based method. The results show that, since no training data were available from regions of Abadeh, Jarqavieh, and Arak, the conventional methods were not able to forecast solar radiation in these regions. This evaluation confirms the high ability of the presented FL approach to make acceptable predictions while preserving privacy and eliminating model reliance on training data.


Asunto(s)
Energía Solar , Humanos , Irán , Aprendizaje Automático , Redes Neurales de la Computación
16.
ACS Appl Polym Mater ; 6(10): 5618-5629, 2024 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-38807950

RESUMEN

This work introduces the encapsulation of hexamethylene diisocyanate derivatives (HDI, TriHDI, and PHDI) with the biodegradable polymer poly(butylene adipate-co-terephthalate) (PBAT) through a solvent evaporation method. These microcapsules (MCs) were then employed in adhesive formulations for footwear. Moreover, MCs containing PHDI were produced in a closed vessel, demonstrating the potential for recovering and reusing organic solvents for the first time. The MCs were achieved with an isocyanate payload reaching up to 68 wt %, displaying a spherical shape, a core-shell structure, and thin walls without holes or cracks. The application of MCs as cross-linking agents for adhesives was evaluated following industry standards. The adhesives' strength surpassed the minimum requirement by a significant margin. Creep tests demonstrated that the formulation with MCs exhibits superior thermostability. Furthermore, the formulation with MCs-PHDI presented the best results reported to date for this type of system, as no displacement was observed in the bonded substrates. Environmental assessment indicates that adhesives with MCs have higher global warming potential (+16.2%) and energy consumption (+10.8%) than the standard commercial adhesives, but under alternative realistic scenarios, the differences can be insignificant. Therefore, adhesive formulations incorporating MCs promise to be on par with traditional adhesive systems regarding environmental impacts while providing benefits such as improved and safe handling of isocyanates and excellent bonding effectiveness.

17.
Polymers (Basel) ; 15(3)2023 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-36771965

RESUMEN

Poly(butylene adipate-co-terephthalate) (PBAT), a biodegradable flexible, and tough polymer is herein used, for the first time, to encapsulate and protect isocyanate derivatives. Isocyanates are essential building blocks widely employed in the chemical industry for the production of high-performing materials. Microencapsulation of isocyanates eliminates the risks associated with their direct handling and protects them from moisture. In light of this, and having in mind eco-innovative products and sustainability, we present a straightforward process to encapsulate isophorone diisocyanate (IPDI) using this biodegradable polymer. Spherical and core-shell microcapsules (MCs) were produced by an emulsion system combined with the solvent evaporation method. The MCs present a regular surface, without holes or cracks, with a thin shell and high isocyanate loadings, up to 79 wt%. Additionally, the MCs showed very good isocyanate protection if not dispersed in organic or aqueous solutions. Effects of various process parameters were systematically studied, showing that a higher stirring speed (1000 rpm) and emulsifier amount (2.5 g), as well as a smaller PBAT amount (1.60 g), lead to smaller MCs and narrower size distribution.

18.
J Mol Model ; 29(8): 241, 2023 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-37436478

RESUMEN

CONTEXT: The design and synthesis of safe and highly active sulfonylurea herbicides is still a challenge. Therefore, following some principles of structure-activity relationship (SAR) of sulfonylurea herbicides, this work focuses on evaluating two sulfonylurea derivatives bearing electron-withdrawing substituents, namely, -(CO)OCH3 and -NO2 on the aryl group, on herbicidal activity. To understand the effects caused by the substituent groups, the molecular and electronic structures of the sulfonylureas were evaluated by density functional theory. Likewise, the crystalline supramolecular arrangements of both compounds were analyzed by Hirshfeld surface, QTAIM, and NBO, with the aim of verifying changes in intermolecular interactions caused by substituent groups. Finally, through a toxicophoric analysis, we were able to predict the interacting groups in their biological target, acetolactate synthase, and verify the interactions with the binding site. METHODS: All theoretical calculations were conducted using the highly parameterized empirical exchange-correlation functional M06-2X accompanied by the diffuse and polarized basis set 6-311++G(d,p). The atomic coordinates were obtained directly from the crystalline structures, and from the energies of the frontier molecular orbitals (HOMO and LUMO), chemical descriptors were obtained that indicated the influence of the functional groups in the sulfonylureas on the reactivity of the molecules. The intermolecular interactions in the crystals were analyzed using the Hirshfeld, QTAIM, and NBO surfaces. Toxicophoric modeling was performed by the PharmaGist webserver and molecular docking calculations were performed by the GOLD 2022.1.0 software package so that the ligand was fitted to the binding site in a 10 Å sphere. For this, genetic algorithm parameters were used using the ChemPLP scoring function for docking and ASP for redocking.


Asunto(s)
Acetolactato Sintasa , Herbicidas , Simulación del Acoplamiento Molecular , Modelos Moleculares , Acetolactato Sintasa/química , Acetolactato Sintasa/metabolismo , Herbicidas/química , Herbicidas/farmacología , Compuestos de Sulfonilurea/química , Compuestos de Sulfonilurea/farmacología , Pirimidinas
19.
Front Chem ; 11: 1267634, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37795387

RESUMEN

Introduction: The green revolution model that is followed in the Brazilian Cerrado is dependent on mechanization, chemical fertilization for soil dressing and correction, and the use of herbicides. Paraquat is a methyl viologen herbicide marketed as bipyridylium dichloride salts and used (in low doses) to combat weeds in their post-emergence stage. It is a non-selective pesticide that causes the peroxidation of the lipids that make up the cell membrane, and when it comes into contact with foliage, it results in the death of the plant. Methods: The effect of water molecules co-crystallized in Paraquat salt structures was analyzed in anhydrous, dihydrate, and trihydrate forms to understand those physicochemical properties in its redox activity. The frontier molecular orbitals were also carried out using DFT to obtain the chemical reactivity of the bipyridylium cation. Finally, the supramolecular arrangements were evaluated to analyze the physicochemical stability and acquire insights on superoxide anions. Results and discussion: The electronic structure indicated that the BP cation presents an acidic character due to its low ELUMO value, while the salt has a more basic character due to its high EHOMO value. For this reason, the BP ion is more susceptible to reduction during the weeds' photosynthesis process. During the process of plant photosynthesis, PQ is reduced to form a stable radical cation. In the supramolecular arrangement, the presence of water molecules increases the number of strong H-bonds, while the weak/moderate H-bonds are stabilized. PQ's toxic effects are observed in wildlife, domesticated animals, human populations, and ecosystems. The influence of PQ on the terrestrial environment is limited because of the soil adsorption capacity associated with good agricultural practices. The current use of good agricultural practices in the Cerrado seems not to prevent the environmental impacts of herbicides like PQ because it aims for the expansion and profitability of large-scale farming based on input-intensive practices instead of sustainable agriculture processes.

20.
Polymers (Basel) ; 16(1)2023 Dec 29.
Artículo en Inglés | MEDLINE | ID: mdl-38201776

RESUMEN

We employed microemulsion combined with the solvent evaporation technique to produce biodegradable polycaprolactone (PCL) MCs, containing encapsulated isophorone diisocyanate (IPDI), to act as crosslinkers in high-performance adhesive formulations. The MC production process was optimized by applying a design of experiment (DoE) statistical approach, aimed at decreasing the MCs' average size. For that, three different factors were considered, namely the concentration of two emulsifiers, polyvinyl alcohol (PVA) and gum arabic (GA); and the oil-to-water phase ratio of the emulsion. The significance of each factor was evaluated, and a predictive model was developed. We were able to decrease the average MC size from 326 µm to 70 µm, maintaining a high encapsulation yield of approximately 60% of the MCs' weight, and a very satisfactory shelf life. The MCs' average size optimization enabled us to obtain an improved distributive and dispersive mixture of isocyanate-loaded MCs at the adhesive bond. The MCs' suitability as crosslinkers for footwear adhesives was assessed following industry standards. Peel tests revealed peel strength values above the minimum required for casual footwear, while the creep test results indicated an effective crosslinking of the adhesive. These results confirm the ability of the MCs to release IPDI during the adhesion process and act as crosslinkers for new adhesive formulations.

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