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1.
Rev. biol. trop ; Rev. biol. trop;72(1): e53238, ene.-dic. 2024. tab, graf
Artículo en Inglés | SaludCR, LILACS | ID: biblio-1559323

RESUMEN

Abstract Introduction: Evidence suggests that herbivores, such as peccaries, shape vegetation structure and diversity through predation, trampling, dispersal, and rooting behavior. Objective: To evaluate the impact of peccaries (Dycotiles tajacu) on the understory vegetation of the tropical rainforest in the Nogal-La Selva Local Biological Corridor, Costa Rica, comparing a site with the absence of peccaries to another with the presence of these animals. Methodology: From June to November 2021, 20 experimental exclusions and 20 free access plots, each measuring 2 m2 were used to quantify herbivory, the number of leaf blades, damaged leaves, healthy leaves, sapling height, and fallen biomass at both sites. Results: A higher sapling density was found in the Nogal Reserve, but a lower sapling diversity, while in La Selva there was a higher sapling diversity, but a lower density of seedlings. Herbivory and sapling height in La Selva exceeded those in Nogal. The exclusion of peccaries reduced seedling damage but did not affect the dynamics of fallen biomass. Conclusion: For the design, implementation, and evaluation of the effectiveness of biological corridors, it is crucial to consider plant-animal interactions to enhance the flow of ecological processes through functional and structural connectivity, analyzed from interactions such as those presented in this paper.


Resumen Introducción: Existe evidencia que herbívoros, como los saínos, dan forma a la estructura y diversidad de la vegetación a través del comportamiento de depredación, pisoteo, dispersión y enraizamiento. Objetivo: Evaluar el impacto de los saínos (Dycotiles tajacu) en la vegetación del sotobosque del bosque tropical húmedo en el Corredor Biológico Local Nogal-La Selva, Costa Rica, en un sitio con ausencia y en otro con presencia de saínos. Métodos: De junio a noviembre de 2021 se utilizaron 20 exclusiones experimentales y 20 parcelas de acceso libre de 2 m2, se cuantifico la herbivoría, número de láminas foliares, hojas dañadas, hojas sanas, altura de brinzales y biomasa caída en ambos sitios. Resultados: Se encontró una mayor densidad de brinzales en Reserva Nogal pero una menor diversidad, contrario en La Selva donde se encontró una mayor diversidad de brinzales, pero una menor densidad de plántulas. La herbivoría y la altura de brinzales en La Selva fue mayor que en Nogal. La exclusión de los saínos disminuyó el daño a las plántulas, pero no afectó la dinámica de la biomasa caída. Conclusión: Es necesario contemplar para el diseño, implementación y evaluación de la efectividad de corredores biológicos, las interacciones planta-animal, para potencializar el flujo de procesos ecológicos mediante la conectividad funcional y estructural, analizada a partir de interacciones como las presentadas en este trabajo.


Asunto(s)
Animales , Artiodáctilos , Bosques , Distribución Animal , Ecosistema Tropical , Costa Rica
2.
Artículo en Inglés | MEDLINE | ID: mdl-39108119

RESUMEN

Ferulic acid is a widely distributed phenolic substance with diverse bioactive properties, which has been widely used in the pharmaceutical, food, and cosmetic industries. Wounds are complex skin lesions to treat and their treatment is long and costly. This encourages the search for alternative treatments, especially in the area of bioactive substances of natural origin. AIMS: This work aims to make a bibliographic survey on studies of the use of ferulic acid in the treatment of wounds. RESULTS: The studies found show that ferulic acid acts through different mechanisms of action such as antioxidant, anti-inflammatory, antimicrobial, collagen production, angiogenic, and reepithelialization effects. These properties act synergistically in different stages of healing, which differentiates it from conventional treatments. In addition, ferulic acid has dermal absorption, low skin metabolism, and low toxicity. CONCLUSION: Studies in this area are recent and further research is needed to expand the possibilities and therapeutic efficiency of ferulic acid in wound healing.

3.
Molecules ; 29(15)2024 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-39124942

RESUMEN

Secondary metabolites produced by fungi are well known for their biological properties, which play important roles in medicine. These metabolites aid in managing infections and treating chronic illnesses, thereby contributing substantially to human health improvement. Despite this extensive knowledge, the vast biodiversity and biosynthetic potential of fungi is still largely unexplored, highlighting the need for further research in natural products. In this review, several secondary metabolites of fungal origin are described, emphasizing novel structures and skeletons. The detection and characterization of these metabolites have been significantly facilitated by advancements in analytical systems, particularly modern hyphenated liquid chromatography/mass spectrometry. These improvements have primarily enhanced sensitivity, resolution, and analysis flow velocity. Since the in vitro production of novel metabolites is often lower than the re-isolation of known metabolites, understanding chromatin-based alterations in fungal gene expression can elucidate potential pathways for discovering new metabolites. Several protocols for inducing metabolite production from different strains are discussed, demonstrating the need for uniformity in experimental procedures to achieve consistent biosynthetic activation.


Asunto(s)
Productos Biológicos , Cromatina , Hongos , Hongos/metabolismo , Cromatina/metabolismo , Productos Biológicos/metabolismo , Metabolismo Secundario , Humanos
4.
Polymers (Basel) ; 16(15)2024 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-39125241

RESUMEN

The forest industry produces several low-value by-products, such as bark, sawdust, limbs, and leaves, that are not ultimately disposed of and remain in the forests and sawmill facilities. Among these by-products are leaves, which contain not only cellulose fibers and lignin but also essential oils such as terpenes. These are biosynthesized in a similar way as cis-1,4-polyisoprene. In this context, this work evaluates the use of screened and unscreened dried Eucalyptus nitens leaves in natural rubber. Among the most relevant results of this work is a significant increase in mechanical properties, such as tensile strength and elongation at break, reaching values of 9.45 MPa and 649% of tensile strength and elongation at break, respectively, for a sample of natural rubber containing sieved dried leaves of Eucalyptus nitens. In addition, it is observed that the content of this vegetable filler allows for inhibiting the antibacterial effect of vulcanized rubber against several bacteria, such as Bacillus subtilis, Staphylococcus aureus, Escherichia coli K 12, Escherichia coli FT 17 and Pseudomonas fluorescens. These results are promising because they not only add value to a by-product of the forestry industry, improving the mechanical properties of natural rubber from a sustainable approach but also increase the affinity of rubber with bacterial microorganisms that may play a role in certain ecosystems.

5.
Trop Anim Health Prod ; 56(7): 232, 2024 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-39096361

RESUMEN

This study aimed to evaluate forage production and ingestive behavior of Morada Nova sheep in an intensive system with capim-tamani grass in both monoculture and silvopastoral irrigated systems in the Semi-arid region. Eighteen adult sheep, approximately 3 years old, with an average body weight of 26.8 ± 4.3 kg, were allocated to treatments with capim-tamani grass cultivated in monoculture and in silvopastoral systems with Caatinga trees. The experiment followed a completely randomized complete block design with two plots and three replications. Forage production, consumption, and behavioral activities were the assessed variables. The animals remained in the pasture daily between 6 am and 6 pm. No effects of the monoculture and silvopastoral systems were observed on the structural and productive characteristics of the capim-tamani grass pasture. There were also no observed effects on body condition score, consumption, and disappearance rate of dry matter (DM) and other nutrients in both systems. However, there was an interaction between the time animals spent under shade in monoculture and silvopastoral systems. In general, the animals spent more time under shade where there were trees, except during the period between 2 pm and 4 pm, when the times were similar. On average, the animals spent approximately 15.6% (equivalent to 1.87 h) of their total time in the artificial shade available in the monoculture system, whereas in the silvopastoral system, they remained under natural shade for approximately 40% (five and a half hours) of their time spent in the pasture during the day. The grazing frequency in both systems was approximately 70% (8.4 h) in relation to the total time spent in the pasture. The capim-tamani grass pasture managed intensively with sheep in the silvopastoral system showed similar forage production and consumption compared to the monoculture system. There was a positive influence of trees on the duration of solar radiation exposure to the animals throughout the day. The results support the need to provide shade for sheep, as well as to promote these sustainable systems in semi-arid regions.


Asunto(s)
Alimentación Animal , Crianza de Animales Domésticos , Conducta Alimentaria , Poaceae , Animales , Crianza de Animales Domésticos/métodos , Alimentación Animal/análisis , Riego Agrícola , Ovinos/fisiología , Oveja Doméstica/fisiología , Masculino , Femenino
6.
Future Microbiol ; 19(15): 1309-1320, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39101446

RESUMEN

Aim: Evaluate the anticandidal effect of Croton heliotropiifolius Kunth essential oil and its interaction with azoles and N-acetylcysteine (NAC) against planktonic cells and biofilms.Materials & methods: Broth microdilution and checkerboard methods were used to evaluate the individual and combined activity with fluconazole and itraconazole (ITRA). The antibiofilm effect of the oil was assessed in 96-well plates alone and combined with ITRA and NAC, and cytotoxicity determined by MTT.Results: The oil inhibited all Candida species growth. The activity was enhanced when associated with ITRA and NAC for planktonic cells and biofilms in formation. The effective concentrations were lower than the toxic ones to V79 cells.Conclusion: C. heliotropiifolius Kunth essential oil is an anticandidal alternative, and can be associated with ITRA and NAC.


Candida is a type of fungus that can cause disease in people. In recent years, the number of available drugs to treat this disease have declined. It is important to search for new drugs. Plants are often used to improve health, so we tested the essential oil of a plant called Croton heliotropiifolius to see if it could kill the fungus. We found that the essential oil could kill the fungus, and could be used with other drugs to improve their effects.


Asunto(s)
Acetilcisteína , Antifúngicos , Biopelículas , Candida , Croton , Itraconazol , Pruebas de Sensibilidad Microbiana , Aceites Volátiles , Croton/química , Aceites Volátiles/farmacología , Aceites Volátiles/química , Itraconazol/farmacología , Antifúngicos/farmacología , Acetilcisteína/farmacología , Biopelículas/efectos de los fármacos , Candida/efectos de los fármacos , Sinergismo Farmacológico , Animales , Línea Celular , Fluconazol/farmacología , Cricetinae
7.
Sci Rep ; 14(1): 18875, 2024 08 14.
Artículo en Inglés | MEDLINE | ID: mdl-39143185

RESUMEN

Chagas disease, caused by Trypanosoma cruzi (T. cruzi), is one of the most important neglected diseases in Latin America. The limited use of the current nitro-derivative-based chemotherapy highlights the need for alternative drugs and the identification of their molecular targets. In this study, we investigated the trypanocidal effect of the sesquiterpene lactone dehydroleucodine (DhL) and its derivatives, focusing on the antioxidative defense of the parasites. DhL and two derivatives, at lesser extent, displayed antiproliferative effect on the parasites. This effect was blocked by the reducing agent glutathione (GSH). Treated parasites exhibited increased intracellular ROS concentration and trypanothione synthetase activity, accompanied by mitochondrial swelling. Although molecular dynamics studies predicted that GSH would not interact with DhL, 1H-NMR analysis confirmed that GSH could protect parasites by interacting with the lactone. When parasites overexpressing mitochondrial tryparedoxin peroxidase were incubated with DhL, its effect was attenuated. Overexpression of cytosolic tryparedoxin peroxidase also provided some protection against DhL. These findings suggest that DhL induces oxidative imbalance in T. cruzi, offering new insights into potential drug targets against this parasite.


Asunto(s)
Lactonas , Especies Reactivas de Oxígeno , Sesquiterpenos , Trypanosoma cruzi , Trypanosoma cruzi/efectos de los fármacos , Trypanosoma cruzi/metabolismo , Sesquiterpenos/farmacología , Lactonas/farmacología , Especies Reactivas de Oxígeno/metabolismo , Tripanocidas/farmacología , Glutatión/metabolismo , Enfermedad de Chagas/tratamiento farmacológico , Enfermedad de Chagas/parasitología , Proteínas Protozoarias/metabolismo , Animales , Mitocondrias/metabolismo , Mitocondrias/efectos de los fármacos , Amida Sintasas
8.
Beilstein J Org Chem ; 20: 1800-1816, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39109298

RESUMEN

Antimicrobial resistance presents a substantial threat to global public health, demanding urgent attention and action. This study focuses on lanthipeptides, ribosomally encoded peptides that display significant structural diversity and hold promising potential as antibiotics. Genome mining was employed to locate biosynthetic gene clusters (BGCs) containing class II lanthipeptide synthetases encoded by lanM genes. A phylogenetic study analyzing homologous sequences of functional LanM sequences revealed a unique evolutionary clade of 17 LanM proteins associated with 12 Clostridium bacterial genomes. In silico exploration identified nine complete BGCs, including one super-cluster containing two co-localized operons from Clostridium cellulovorans 743B, that encode for two new peptides named clostrisin and cellulosin. Each operon was heterologously expressed in Escherichia coli. Molecular weights associated with the expected post-translational modifications of the purified lanthipeptide were confirmed by MS-MS/MS analysis for cellulosin, while clostrisin was not post-translationally modified. Both peptides demonstrated antimicrobial activity against multidrug-resistant bacteria, such as a clinical strain of Staphylococcus epidermidis MIQ43 and Pseudomonas aeruginosa PA14. This is the first report of lanthipeptides from the Clostridium genus produced with its native biosynthetic machinery, as well as chemically and biologically characterized. This study showcases the immense potential of genome mining in identifying new RiPP synthetases and associated bioactive peptides.

9.
Int J Biometeorol ; 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39136712

RESUMEN

Soybean (Glycine max) is the world's most cultivated legume; currently, most of its varieties are Bt. Spodoptera spp. (Lepidoptera: Noctuidae) are important pests of soybean. An artificial neural network (ANN) is an artificial intelligence tool that can be used in the study of spatiotemporal dynamics of pest populations. Thus, this work aims to determine ANN to identify population regulation factors of Spodoptera spp. and predict its density in Bt soybean. For two years, the density of Spodoptera spp. caterpillars, predators, and parasitoids, climate data, and plant age was evaluated in commercial soybean fields. The selected ANN was the one with the weather data from 25 days before the pest's density evaluation. ANN forecasting and pest densities in soybean fields presented a correlation of 0.863. It was found that higher densities of the pest occurred in dry seasons, with less wind, higher atmospheric pressure and with increasing plant age. Pest density increased with the increase in temperature until this curve reached its maximum value. ANN forecasting and pest densities in soybean fields in different years, seasons, and stages of plant development were similar. Therefore, this ANN is promising to be implemented into integrated pest management programs in soybean fields.

10.
Artículo en Inglés | MEDLINE | ID: mdl-39136738

RESUMEN

Euphorbiaceae is a family of dicotyledonous angiosperm plants that occur mainly in the tropics and produce a variety of secondary metabolites. Given the abundance of the Euphorbiaceae species and the diversity of substances they produce, this study aims to investigate paten documents concerning inventions and models involving the pharmacological use of these species, contributing to the study of their medicinal potential. The present review delves into patent documents in the Patentscope database, from the application of search criteria, such as "simple search" with the "Euphorbiaceae" keyword, limited to the front page, with stemming, without language limitation, from any patent office, and excluding non-patent literature (NPL). The selected patents were prevalently published in East Asian offices between 1998 and 2023, including 41 species of Euphorbiaceae of 19 genera, with 31 metabolites represented. The collected metabolites predominantly exhibited anti-tumoral (N = 21), anti-inflammatory (N = 10), antioxidant (N = 7), and anti-bacterial (N = 6) activities. Additionally, some substances have shown valid properties for treating non-communicable diseases (N = 8). The patents demonstrate the biotechnological potential of species from the Euphorbiaceae family, which are exceptionally satile regarding their applications in the health sector. However, the small number of patents that identify specific metabolites hinders a more thorough investigation of the activities of the products extracted from these species.

11.
Compr Rev Food Sci Food Saf ; 23(5): e13427, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39137002

RESUMEN

Colletotrichum spp. is a phytopathogen causing anthracnose in a variety of tropical fruits. Strategies used to control postharvest diseases in tropical fruits typically rely on the use of synthetic fungicides, which have stimulated the emergence of resistant pathogens. Safer alternative strategies to control anthracnose in tropical fruits have been described in the literature. This review presents and discusses the main innovative interventions concerning the application of sustainable alternative strategies in the postharvest control of pathogenic Colletotrichum species in tropical fruits, with a particular emphasis on the studies published in the last 5 years. The available studies have shown the use of various methods, including physical barriers, natural antimicrobials, and biological control with antagonistic microorganisms, to reduce anthracnose lesion severity and incidence in tropical fruits. The available literature showed high inhibitory activity in vitro, reduced anthracnose incidence and lesion diameter, and total disease inhibition in tropical fruits. Most studies focused on the inhibition of Colletotrichum gloeosporioides on avocado, papaya, and mango, as well as of Colletotrichum musae on banana; however, the inhibition of other Colletotrichum species was also demonstrated. The application of emerging sustainable alternative methods, including natural antimicrobial substances, also stimulated the induction of defense systems in tropical fruits, including enzymatic activity, such as polyphenol oxidase, peroxidase, and phenylalanine ammonia-lyase. The retrieved data helped to understand the current state of the research field and reveal new perspectives on developing efficient and sustainable intervention strategies to control pathogenic Colletotrichum species and anthracnose development in tropical fruits.


Asunto(s)
Colletotrichum , Frutas , Enfermedades de las Plantas , Frutas/microbiología , Enfermedades de las Plantas/microbiología , Enfermedades de las Plantas/prevención & control , Conservación de Alimentos/métodos , Clima Tropical , Fungicidas Industriales/farmacología
12.
Acta Parasitol ; 69(3): 1426-1438, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39147955

RESUMEN

PURPOSE: The flea Ctenocephalides felis (Siphonaptera: Pulicidae), parasitizes dogs and cats globally, acting as a vector for various pathogens affecting both animals and humans. Growing interest in environmentally friendly, plant-based products prompted this study. The aim of the study was to determine the chemical composition of essential oils (EOs) from Copaifera reticulata, Citrus paradisi, Lavandula hybrida and Salvia sclarea, assessing their insecticidal and repellent properties, determining lethal concentrations (LC50 and LC90), and evaluating residual efficacy in vitro against Ctenocephalides felis felis. METHODS: Gas Chromatography with Flame Ionization Detector analyzed EO composition. In vitro tests involved preparing EO solutions at various concentrations. Ten specimens from each life stage (egg, larva, pupa, adult) were used for insecticidal activity assessment. Adulticidal activity was assessed using 10 cm2 filter paper strip, each treated with 0.200 mL of the test solution. Immature stages activities were evaluated using 23.76 cm2 discs of the same filter paper, each treated with 0.470 mL of the test solution. Mortality percentage was calculated using (number of dead insects × 100) / number of incubated insects. Probit analysis calculated LC50 values with a 95% confidence interval. RESULTS: Major EO constituents were ß-caryophyllene (EOCR), linalool (EOLH), linalyl acetate (EOSS), and limonene (EOCP). LC50 values were obtained for all stages except for the essential oil of C. paradisi. All oils showed repellent activity at 800 µg/cm2. OECR exhibited greater residual efficacy. CONCLUSION: Each EO demonstrated superior insecticidal activity against specific C. felis felis stages.


Asunto(s)
Ctenocephalides , Repelentes de Insectos , Insecticidas , Aceites Volátiles , Salvia , Animales , Aceites Volátiles/farmacología , Aceites Volátiles/química , Salvia/química , Repelentes de Insectos/farmacología , Repelentes de Insectos/química , Insecticidas/farmacología , Insecticidas/química , Ctenocephalides/efectos de los fármacos , Fabaceae/química , Lavandula/química , Larva/efectos de los fármacos , Pupa/efectos de los fármacos , Citrus/química , Monoterpenos Acíclicos/farmacología , Monoterpenos/farmacología , Monoterpenos/química , Aceites de Plantas/farmacología , Aceites de Plantas/química , Dosificación Letal Mediana
13.
Rev. obstet. ginecol. Venezuela ; 84(3): 329-334, Ago. 2024.
Artículo en Español | LILACS, LIVECS | ID: biblio-1570398

RESUMEN

El parto humanizado es un modelo de atención que considera el respeto a las opiniones y necesidades de las mujeres y sus familias, e incluye la atención durante el embarazo, parto, puerperio y, por supuesto, la atención del recién nacido. En Venezuela, existe legislación suficiente que respalda la atención del parto humanizado o respetado, sin embargo, la misma no es conocida por gran parte del personal de salud involucrado en la atención obstétrica. Es necesario que tal legislación se conozca ampliamente y se aplique. La presente revisión se realizó con la intención de revisar los fundamentos legales que respaldan la atención del parto respetado(AU)


Humanized childbirth is a model of care that considers respect for the opinions and needs of women and their families, and includes care during pregnancy, childbirth, puerperium and, of course, newborn care. In Venezuela, there is sufficient legislation that supports humanized or respected childbirth care, however, it is not known by a large part of the health personnel involved in obstetric care. Such legislation needs to be widely known and implemented. This review was conducted with the intention of reviewing the legal foundations that support respected childbirth care(AU)


Asunto(s)
Humanos , Femenino , Personal de Salud , Parto Humanizado , Normas Jurídicas , Mujeres Embarazadas , Trabajo de Parto , Hospitales , Jurisprudencia
14.
Foods ; 13(13)2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38998505

RESUMEN

Numerous natural antioxidants commonly found in our daily diet have demonstrated significant benefits for human health and various diseases by counteracting the impact of reactive oxygen and nitrogen species. Their chemical properties enable a range of biological actions, including antihypertensive, antimicrobial, anti-inflammatory, anti-fibrotic, and anticancer effects. Despite promising outcomes from preclinical studies, ongoing debate persists regarding their reproducibility in human clinical models. This controversy largely stems from a lack of understanding of the pharmacokinetic properties of these compounds, coupled with the predominant focus on monotherapies in research, neglecting potential synergistic effects arising from combining different antioxidants. This study aims to provide an updated overview of natural antioxidants, operating under the hypothesis that a multitherapeutic approach surpasses monotherapy in efficacy. Additionally, this study underscores the importance of integrating these antioxidants into the daily diet, as they have the potential to prevent the onset and progression of various diseases. To reinforce this perspective, clinical findings pertaining to the treatment and prevention of non-alcoholic fatty liver disease and conditions associated with ischemia and reperfusion phenomena, including myocardial infarction, postoperative atrial fibrillation, and stroke, are presented as key references.

15.
Foods ; 13(13)2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38998616

RESUMEN

When looking for new ingredients to process red meat, poultry, and fish products, it is essential to consider using vegetable resources that can replace traditional ingredients such as animal fat and synthetic antioxidants that may harm health. The Amazon, home to hundreds of edible fruit species, can be a viable alternative for new ingredients in processing muscle food products. These fruits have gained interest for their use as natural antioxidants, fat replacers, colorants, and extenders. Some of the fruits that have been tested include açai, guarana, annatto, cocoa bean shell, sacha inchi oil, and peach palm. Studies have shown that these fruits can be used as dehydrated products or as liquid or powder extracts in doses between 250 and 500 mg/kg as antioxidants. Fat replacers can be added directly as flour or used to prepare emulsion gels, reducing up to 50% of animal fat without any detrimental effects. However, oxidation problems of the gels suggest that further investigation is needed by incorporating adequate antioxidant levels. In low doses, Amazon fruit byproducts such as colorants and extenders have been shown to have positive technological and sensory effects on muscle food products. While evidence suggests that these fruits have beneficial health effects, their in vitro and in vivo nutritional effects should be evaluated in muscle food products containing these fruits. This evaluation needs to be intended to identify safe doses, delay the formation of key oxidation compounds that directly affect health, and investigate other factors related to health.

16.
Molecules ; 29(13)2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38999016

RESUMEN

The concept of uncertainty in an isotopic analysis is not uniform in the scientific community worldwide and can compromise the risk of false compliance assessment applied to carbon isotopic analyses in natural gas exploratory evaluation. In this work, we demonstrated a way to calculate one of the main sources of this uncertainty, which is underestimated in most studies focusing on gas analysis: the δ13C calculation itself is primarily based on the raw analytical data. The carbon isotopic composition of methane, ethane, propane, and CO2 was measured. After a detailed mathematical treatment, the corresponding expanded uncertainties for each analyte were calculated. Next, for the systematic isotopic characterization of the two gas standards, we calculated the standard uncertainty, intermediary precision, combined standard uncertainty, and finally, the expanded uncertainty for methane, ethane, propane, and CO2. We have found an expanded uncertainty value of 1.8‰ for all compounds, except for propane, where a value of 1.6‰ was obtained. The expanded uncertainty values calculated with the approach shown in this study reveal that the error arising from the application of delta calculation algorithms cannot be neglected, and the obtained values are higher than 0.5‰, usually considered as the accepted uncertainty associated with the GC-IRMS analyses. Finally, based on the use of uncertainty information to evaluate the risk of false compliance, the lower and upper acceptance limits for the carbon isotopic analysis of methane in natural gas are calculated, considering the exploratory limits between -55‰ and -50‰: (i) for the underestimated current uncertainty of 0.5‰, the lower and upper acceptance limits, respectively, are -54.6‰ and -50.4‰; and (ii) for the proposed realistic uncertainty of 1.8‰, the lower and upper acceptance limits would be more restrictive; i.e., -53.5‰ and -51.5‰, respectively.

17.
Int J Mol Sci ; 25(13)2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-39000607

RESUMEN

Natural killer (NK) cells play a crucial role in innate immunity, particularly in combating infections and tumors. However, in hematological cancers, NK cells often exhibit impaired functions. Therefore, it is very important to activate its endosomal Toll-like receptors (TLRs) as a potential strategy to restore its antitumor activity. We stimulated NK cells from the peripheral blood mononuclear cells from children with acute lymphoblastic leukemia and NK cells isolated, and the NK cells were stimulated with specific TLR ligands (Poly I:C, Imiquimod, R848, and ODN2006) and we evaluated changes in IFN-γ, CD107a, NKG2D, NKp44 expression, Granzyme B secretion, cytokine/chemokine release, and cytotoxic activity. Results revealed that Poly I:C and Imiquimod enhanced the activation of both immunoregulatory and cytotoxic NK cells, increasing IFN-γ, CD107a, NKG2D, and NKp44 expression. R848 activated immunoregulatory NK cells, while ODN2006 boosted CD107a, NKp44, NKG2D, and IFN-γ secretion in cytotoxic NK cells. R848 also increased the secretion of seven cytokines/chemokines. Importantly, R848 and ODN 2006 significantly improved cytotoxicity against leukemic cells. Overall, TLR stimulation enhances NK cell activation, suggesting TLR8 (R848) and TLR9 (ODN 2006) ligands as promising candidates for antitumor immunotherapy.


Asunto(s)
Imiquimod , Células Asesinas Naturales , Activación de Linfocitos , Poli I-C , Leucemia-Linfoma Linfoblástico de Células Precursoras , Receptores Toll-Like , Humanos , Células Asesinas Naturales/inmunología , Células Asesinas Naturales/efectos de los fármacos , Células Asesinas Naturales/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras/inmunología , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamiento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/patología , Poli I-C/farmacología , Activación de Linfocitos/efectos de los fármacos , Activación de Linfocitos/inmunología , Imiquimod/farmacología , Receptores Toll-Like/metabolismo , Receptores Toll-Like/agonistas , Niño , Oligodesoxirribonucleótidos/farmacología , Citocinas/metabolismo , Femenino , Interferón gamma/metabolismo , Masculino , Imidazoles/farmacología , Citotoxicidad Inmunológica/efectos de los fármacos , Preescolar , Agonistas de los Receptores Toll-Like
18.
Anim Reprod ; 21(2): e20240012, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39021496

RESUMEN

This study aimed to investigate the effect of including mouse feed with different concentrations (5, 10, or 20%) of Pereskia aculeata Miller (PAM) leaves on the morphology and development of preantral ovarian follicles and ovarian stromal cell density. The oral toxicity was performed using repeated dose toxicity assays subdivided into experiments of 30 days and 90 days of treatment. After the experiments, the ovaries of each animal were collected and submitted to classical histology. At 30 and 90 days, there was an equivalent percentage of normal, primordial, and developing follicles (P > 0.05) between PAM treatments compared to the control. Regarding the different stages of follicular development, after 90 days, there was a higher percentage (P < 0.05) of developing follicles only in the control group compared to day 30. The PAM 5% treatment was the only one that affected the cell density in the stroma after 90 days of treatment. Thus, we observed that supplementing the diet with P. aculeata did not pose any risk concerning animal consumption; specifically, there were no toxic reproductive effects observed from adding Pereskia aculeata Miller to the mouse diet.

19.
Mol Inform ; 43(7): e202400052, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38994633

RESUMEN

Compound databases of natural products play a crucial role in drug discovery and development projects and have implications in other areas, such as food chemical research, ecology and metabolomics. Recently, we put together the first version of the Latin American Natural Product database (LANaPDB) as a collective effort of researchers from six countries to ensemble a public and representative library of natural products in a geographical region with a large biodiversity. The present work aims to conduct a comparative and extensive profiling of the natural product-likeness of an updated version of LANaPDB and the individual ten compound databases that form part of LANaPDB. The natural product-likeness profile of the Latin American compound databases is contrasted with the profile of other major natural product databases in the public domain and a set of small-molecule drugs approved for clinical use. As part of the extensive characterization, we employed several chemoinformatics metrics of natural product likeness. The results of this study will capture the attention of the global community engaged in natural product databases, not only in Latin America but across the world.


Asunto(s)
Productos Biológicos , Productos Biológicos/química , Productos Biológicos/farmacología , América Latina , Bibliotecas de Moléculas Pequeñas/farmacología , Bibliotecas de Moléculas Pequeñas/química , Descubrimiento de Drogas , Quimioinformática , Bases de Datos de Compuestos Químicos
20.
J Food Sci Technol ; 61(9): 1778-1789, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39049917

RESUMEN

The color of grape juice is an important acceptance attribute by consumers, but it suffers losses during storage. The use of commercial antioxidants has limitations because the concept of a "100% natural drink" of Brazilian legislation. This work characterized Brazilian grape seeds, and the cultivar extract with the greatest potential was encapsulated in arabic-gum (encapsulated extract-EE) to evaluate the color stabilizing capacity. The EE used in the grape juice was compared with the commercial antioxidants sulphite and enological tannin during storage (150 days). The BRS Magna and BRS Violeta grape seeds had the highest phenolic content, and the EE showed high catechin (4108 mg/kg), epicatechin (1161 mg/kg) and procyanidin-B2 (905 mg/kg) values. Sulfite was found to be the best color stabilizer. The use of EE (0.5 g/L) in grape juice improved color stability and anthocyanin stability. It was demonstrated that encapsulated grape seed extract has color stabilizing potential and that Brazilian grape seeds are a raw material of high technological value. Supplementary Information: The online version contains supplementary material available at 10.1007/s13197-024-05956-8.

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