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Understanding leaf generation dynamics, their seasonal changes, and their responses to nitrogen fertilization (NF) is key to improving pasture utilization efficiency. The objectives of this research were to determine structural and morphogenetic variables underlying changes in herbage mass on a set of Paspalum notatum genotypes. Ten P. notatum genotypes were evaluated in experimental plots following a completely randomized block design under a split-plot arrangement for two N-rates during four periods. Increased herbage mass (HM) after N-fertilization was explained by a higher tiller density (TD) (41.8%) and tiller weight (TW) (22.1%). The increment of TW after NF was due to the increase in leaf blade length (LBL) and width (LBW). During the flowering season, NF increases the reproductive tiller density by 262.5%. Seasonal variation in HM was mainly explained by changes in LBL that modified TW. Morphogenetic traits differed between genotypes of different growth habits; therefore, different management practices are suggested. The average increase in leaf elongation rate in response to NF was about 36.7%, generating longer leaves despite reductions in leaf elongation time (LET). The depletion in LBL and consequently in TW and HM during the autumn was attributed to the reduction in LET.

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The genetic systems of Paspalum species have not been extensively studied. We analyzed the ploidy, reproductive mode, mating system, and fertility of four Paspalum species-Paspalum durifolium, Paspalum ionanthum, Paspalum regnellii, and Paspalum urvillei. An analysis of 378 individuals from 20 populations of northeastern Argentina was conducted. All populations of the four Paspalum species were pure tetraploid and had a sexual and stable reproductive mode. However, some populations of P. durifolium and P. ionanthum showed low levels of apospory. Populations of P. durifolium and P. ionanthum had low seed sets under self-pollination but were fertile under open pollination, showing that self-incompatibility likely caused self-sterility. In contrast, populations of P. regnellii or P. urvillei showed no evidence of apospory, and seed sets in both self- and open pollination conditions were high, suggesting that they are self-compatible due to the absence of pollen-pistil molecular incompatibility mechanisms. The evolutionary origin of the four Paspalum species could explain these differences. This study supplies valuable insights into the genetic systems of Paspalum species, which could have implications for their conservation and management.

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The tetraploid germplasm of Paspalum contains a large diversity that can be used to generate better forages. The objective was to evaluate a group of Paspalum notatum and Paspalum simplex apomictic hybrids for a set of agronomic traits and apomixis expressivity. Forage yield, cold tolerance, winter regrowth, and seed yield were evaluated. The expressivity of apomixis was evaluated in P. simplex hybrids by flow cytometry. Progeny testing with molecular markers was used to determine the genotypic variability in the progeny. Differences within P. notatum and P. simplex hybrids were observed for all traits, and some of them were superior in comparison with the controls. The accumulated forage yield during three years was 988 g m-2 in the P. notatum hybrids, whereas, in P. simplex, the average forage yield per harvest (40 days of regrowth) was 180 g m-2. In P. simplex, the apomixis expressivity varied between 0 and 100%, and 65% of the hybrids showed high apomixis expressivity (superior to 70%). The genotypic mean homogeneity in the progeny was 76% and 85% in P. notatum and P. simplex, respectively. The generation of hybrids with high apomixis expressivity that combine good agronomic performance and homogeneity in the offspring is possible in tetraploid P. notatum and P. simplex.

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Metabolic syndrome (MetS) is a risk factor for the development of cardiovascular disease (CVD) and atherosclerosis through a mechanism that involves vascular smooth muscle cell (VSMC) proliferation, lipotoxicity and glucotoxicity. Several molecules found to be increased in MetS, including free fatty acids, fatty acid binding protein 4, leptin, resistin, oxidized lipoprotein particles, and advanced glycation end products, influence VSMC proliferation. Most of these molecules act through their receptors on VSMCs by activating several signaling pathways associated with ROS generation in various cellular compartments. ROS from NADPH-oxidase and mitochondria have been found to promote VSMC proliferation and cell cycle progression. In addition, most of the natural or synthetic substances described in this review, including pharmaceuticals with hypoglycemic and hypolipidemic properties, attenuate VSMC proliferation by their simultaneous modulation of cell signaling and their scavenging property due to the presence of a phenolic ring in their structure. This review discusses recent data in the literature on the role that several MetS-related molecules and ROS play in the change from contractile to proliferative phenotype of VSMCs. Hence the importance of proposing an appropriate strategy to prevent uncontrolled VSMC proliferation using antioxidants, hypoglycemic and hypolipidemic agents.

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This paper introduces a deep learning based methodology for analyzing the self-assembled, fractal-like structures formed in evaporated droplets. To this end, an extensive image database of such structures of the plant extract Viscum album Quercus [Formula: see text] was used, prepared by three different mixing procedures (turbulent, laminar, and diffusion based). The proposed pattern analysis approach is based on two stages: (1) automatic selection of patches that exhibit rich texture along the database; and (2) clustering of patches in accordance with prevalent texture by means of a Dense Convolutional Neural Network. The fractality of the patterns in each cluster is verified through Local Connected Fractal Dimension histograms. Experiments with Gray-Level Co-Occurrence matrices are performed to determine the benefit of the proposed approach in comparison with well established image analysis techniques. For the investigated plant extract, significant differences were found between the production modalities; whereas the patterns obtained by laminar flow showed the highest fractal structure, the patterns obtained by the application of turbulent mixture exhibited the lowest fractality. Our approach is the first to analyze, at the pure image level, the clustering properties of regions of interest within a database of evaporated droplets. This allows a greater description and differentiation of the patterns formed through different mixing procedures.

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Cyclopeptide alkaloids with different biological activities are present in plants of the family Rhamnaceae. Plants of this family grow in a symbiotic relationship with aerobic Gram-positive actinomycetes belonging to the genus Frankia. This goal of this research was a study of the comparative profile of alkaloids present in Discaria chacaye and to establish a connection between the presence or absence of Frankia sp. and the alkaloids. In addition, insecticidal activities of the alkaloidal extract were examined. A total of 24 alkaloids were identified, of which 12 have a benzylisoquinoline skeleton, 9 were cyclopeptides, 2 isoquinolines, and 1 aporphine. The presence of cyclopeptide alkaloids is associated with Frankia nodules in the plant root. The alkaloid extracts showed insecticidal activity with mortality dose-dependence and LD50 values between 44 to 71 µg/mL.

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Contexto la infección de vías urinarias (IVU), causada por adenovirus (ADV) posterior al trasplante renal, tiene el potencial de causar disfunción o pérdida del injerto. La presentación clínica es variable y el tratamiento difiere según la disponibilidad de medicamentos en el medio y la experiencia clínica. Objetivo el estudio describe las características clínicas, de laboratorio y la respuesta al tratamiento de una serie de casos de pacientes trasplantados renales con IVU por ADV en un hospital de Cali, Colombia. Metodología estudio retrospectivo que incluye a todos los pacientes adultos trasplantados con diagnóstico de IVU por ADV entre enero del 2015 hasta enero del 2021. El diagnóstico se realizó basado en la clínica, el resultado positivo de la prueba de reacción de cadena de polimerasa (PCR) y la carga viral del ADV. Resultados de 256 pacientes trasplantados, ocho presentaron diagnóstico de cistitis hemorrágica o nefritis intersticial secundaria a infección por ADV. Se presentó de forma temprana (≤ 3 meses) en el 62 % de los casos, quienes debutaron con macrohematuria asociada a piuria estéril y linfopenia. Por otra parte, se presentó alteración en la función renal en el 87,5 % de los casos y la reducción de la inmunosupresión fue el pilar fundamental en el manejo clínico. Conclusiones el reconocimiento de la infección por ADV en pacientes trasplantados renales ha ido en aumento. La sospecha clínica es clave para el diagnóstico (macrohematuria, síntomas urinarios irritativos y falla renal) y la reducción de la dosis de inmunosupresión para restaurar la función inmune puede ser suficiente en la resolución de la infección y la reversión de la disfunción renal.

Introduction Urinary tract infection (UTI) caused by adenovirus (ADV) after kidney transplantation has the potential to cause graft dysfunction or loss. The clinical presentation is variable, from an asymptomatic course to a multisystemic compromise. Treatment varies based on the availability of different medications and clinical experience. Objective The study describe the clinical, laboratory characteristics and results of a series of cases of kidney transplant patients with hemorrhagic cystitis secondary to ADV infection in a hospital in Cali, Colombia. Methods Retrospective study based on the records of patients with a diagnosis of UTI caused by ADV between January 2015 to January 2021 were included. The diagnosis was made by clinical suspicion and polymerase chain reaction (PCR) - Adenovirus DNA viral load. Results Of 256 transplant patients, eight patients had a diagnosis of hemorrhagic cystitis or interstitial nephritis secondary to ADV infection. It presented early (≤ 3 months) in 62%, who presented with macrohematuria, associated with sterile pyuria and lymphopenia. Alterations in renal function were presented in 87.5%. The reduction of immunosuppression was the fundamental pillar in the management. Conclusions The recognition of ADV infection in kidney transplant patients has been increasing. Clinical suspicion is the key for the diagnosis, with a predominance of macrohematuria, irritative urinary symptoms and kidney graft dysfunction. Reducing the dose of immunosuppression by restoring immune function may be sufficient in resolving the infection and reversing renal dysfunction.

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In order to find molecules of natural origin with potential biological activities, we isolate and synthesise compounds with agarofuran skeletons (epoxyeudesmanes). From the seeds of Maytenus disticha and Maytenus magellanica we obtained six dihydro-ß-agarofurans, and by means of the Robinson annulation reaction we synthesised five compounds with the same skeleton. The structures were established on the basis of NMR, IR, and MS. The evaluated compounds showed inhibitory activity on the acetylcholinesterase enzyme and on the COX enzymes. Compound 4 emerged as the most potent in the acetylcholinesterase inhibition assay with IC50 17.0 ± 0.016 µM on acetylcholinesterase (AChE). The compounds evaluated were shown to be selective for AChE. The molecular docking, and the propidium displacement assay suggested that the compounds do not bind to the active site of the enzyme AChE, but rather bind to the peripheral anionic site (PAS) of the enzyme, on the other hand, the natural compound 8, showed the best inhibitory activity on the COX-2 enzyme with an IC50 value of 0.04 ± 0.007 µM. The pharmacokinetic profile calculated in silico using the SWISSADME platform shows that these molecules could be considered as potential drugs for the treatment of neurodegenerative diseases such as AD.

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The purpose of this study was to determine the inhibitory capacity of ceanothanes triterpenes isolate from Chilean Rhamnaceae on acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) enzymes. Seven ceanothanes triterpenes were isolated from aerial parts of plant material by classical phytochemical methods or prepared by the hemisynthetic method. Structures were determined by the spectroscopic method (1H-NMR and 13C NMR) and mass spectrometry (MS). AChE and BChE activity were determined by the Ellmann method for all compounds. All tested compounds exerted a greater affinity to AChE than to BChE, where compound 3 has an IC50 of 0.126 uM for AChE and of >500 uM to BChE. Kinetic studies indicated that its inhibition was competitive and reversible. According to the molecular coupling and displacement studies of the propidium iodide test, the inhibitory effect of compound 3 would be produced by interaction with the peripheral anionic site (PAS) of AChE. The compounds tested (1−7) showed an important inhibitory activity of AChE, binding to PAS. Therefore, inhibitors that bind to PAS would prevent the formation of the AChE-Aß complex, constituting a new alternative in the treatment of Alzheimer's disease (AD).

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The droplet evaporation method (DEM) is based on the evaporation-induced pattern formation in droplets and is applied mainly for medical diagnosis[1].Here, we present aseries of experiments performed by our team showing DEMs potential also forhomeopathy basic research, in particular, for the investigation of(i) low potencies, (ii) low potency complexes (physical model), and (iii) the action of high potencies (plant-based model).Methods:(i) DEM differentiated significantly between Luffa, Baptisia, Echinacea, and Spongiauntil 4x[2]. Furthermore, the patterns varied in function of the numberof succussion strokes (0, 10, or 100) applied during potentization[3]. The performance of chaotic succussions vs. laminar flow vs. slight mixing during the potentization of Viscum album quercus3x influenced the DEM patterns; the chaotic succussions reduced, whereas laminar flow enhanced the patterns complexity vs. the unsuccussed control.(ii) The addition of Mercurius bijodatus9x to Luffa4x changed significantly the DEM patterns, even if the material quantity present in the 9x potency lied far beyond that of ultrapure water.(iii) Leakages obtained by placing healthy or arsenic-damaged wheat-seeds into Arsenicum album45x orheat-damaged intoZincum metallicum30c vs. water created significantly different DEM structures [4, 5]. Results:The damaged seeds put into the potency created structures characterized by a higher complexity than those obtained from damaged seeds put into control water. Furthermore, the potency action seemed to increase with rising numbers ofsuccussion strokes applied during potentization,ascould be shown by means of DEM patterns and germination rate using the same wheat-seed model[6].In all our studies, the pattern evaluation was computerized (texture and fractal analysis performed by means of ImageJ) or based on deep-learning algorithms and the robustness of the experimental system was checked by means of systematic control experiments.Conclusion:DEM together with other similarmethods has also been reviewed by our team for what concerns theapplication in homeopathy basic research[7].

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