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Antimicrobial coatings provide protection against microbes colonization on surfaces. This can prevent the stabilization and proliferation of microorganisms. The ever-increasing levels of microbial resistance to antimicrobials are urging the development of alternative types of compounds that are potent across broad spectra of microorganisms and target different pathways. This will help to slow down the development of resistance and ideally halt it. The development of composite antimicrobial coatings (CACs) that can host and protect various antimicrobial agents and release them on demand is an approach to address this urgent need. In this work, new CACs based on microsized hybrids of calcium carbonate (CaCO3) and silver nanoparticles (AgNPs) were designed using a drop-casting technique. Polyvinylpyrrolidone and mucin were used as additives. The CaCO3/AgNPs hybrids contributed to endowing colloidal stability to the AgNPs and controlling their release, thereby ensuring the antibacterial activity of the coatings. Moreover, the additives PVP and mucin served as a matrix to (i) control the distribution of the hybrids, (ii) ensure mechanical integrity, and (iii) prevent the undesired release of AgNPs. Scanning electron microscopy (SEM), X-ray diffraction (XRD), and Fourier transform infrared (FTIR) techniques were used to characterize the 15 µm thick CAC. The antibacterial activity was determined against Escherichia coli, methicillin-resistant Staphylococcus aureus (MRSA), and Pseudomonas aeruginosa, three bacteria responsible for many healthcare infections. Antibacterial performance of the hybrids was demonstrated at concentrations between 15 and 30 µg/cm2. Unloaded CaCO3 also presented bactericidal properties against MRSA. In vitro cytotoxicity tests demonstrated that the hybrids at bactericidal concentrations did not affect human dermal fibroblasts and human mesenchymal stem cell viability. In conclusion, this work presents a simple approach for the design and testing of advanced multicomponent and functional antimicrobial coatings that can protect active agents and release them on demand.
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Antibacterianos , Carbonato de Calcio , Ensayo de Materiales , Nanopartículas del Metal , Pruebas de Sensibilidad Microbiana , Tamaño de la Partícula , Plata , Carbonato de Calcio/química , Carbonato de Calcio/farmacología , Plata/química , Plata/farmacología , Antibacterianos/farmacología , Antibacterianos/química , Antibacterianos/síntesis química , Nanopartículas del Metal/química , Humanos , Supervivencia Celular/efectos de los fármacos , Materiales Biocompatibles Revestidos/química , Materiales Biocompatibles Revestidos/farmacología , Escherichia coli/efectos de los fármacos , Propiedades de Superficie , Staphylococcus aureus/efectos de los fármacosRESUMEN
Artemisinin, a drug used to treat malaria, can be chemically synthesized or extracted from Artemisia annua L. However, the extraction method for artemisinin from biomass needs to be more sustainable while maintaining or enhancing its bioactivity. This work investigates the use of aqueous solutions of salts and ionic liquids with hydrotropic properties as alternative solvents for artemisinin extraction from Artemisia annua L. Among the investigated solvents, aqueous solutions of cholinium salicylate and sodium salicylate were found to be the most promising. To optimize the extraction process, a response surface method was further applied, in which the extraction time, hydrotrope concentration, and temperature were optimized. The optimized conditions resulted in extraction yields of up to 6.50 and 6.44 mg·g-1, obtained with aqueous solutions of sodium salicylate and cholinium salicylate, respectively. The extracts obtained were tested for their antimalarial activity, showing a higher efficacy against the Plasmodium falciparum strain compared with pure (synthetic) artemisinin or extracts obtained with conventional organic solvents. Characterization of the extracts revealed the presence of artemisinin together with other compounds, such as artemitin, chrysosplenol D, arteannuin B, and arteannuin J. These compounds act synergistically with artemisinin and enhance the antimalarial activity of the obtained extracts. Given the growing concern about artemisinin resistance, the results here obtained pave the way for the development of sustainable and biobased antimalarial drugs.
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Implant-associated severe infections can result in catastrophic implant failures; thus, advanced antibacterial coatings are needed to combat infections. This study focuses on harnessing nature-inspired self-assembly of extracellular matrix (ECM)-like coatings on Ti alloy with a combination of jellyfish-derived collagen (J-COLL) and hyaluronic acid (HA) using our customized automated hybrid layer-by-layer apparatus. To improve the anti-infection efficacy of coatings, we have incorporated a natural antibacterial agent methylglyoxal (MGO, a Manuka honey compound) in optimized multilayer coatings. The obtainment of MGO-loaded multilayer coatings was successfully assessed by profilometry, contact angle, attenuated total reflectance (ATR)-Fourier transform infrared spectroscopy, scanning electron microscopy, and X-ray photoelectron spectroscopy. In vitro degradation confirmed the controlled release activity of MGO with a range of concentrations from 0.90 to 2.38 mM up to 21 days. A bacterial cell culture study using Escherichia coli (E. coli) and Staphylococcus epidermidis (S. epidermidis) confirmed that the MGO incorporated within layers 7 and 9 had a favorable effect on preventing bacterial growth and colonization on their surfaces. An in vitro cytocompatibility study confirmed that MGO agents included in the layers did not affect or reduce the cellular functionalities of L929 fibroblasts. In addition, MGO-loaded layers with Immortalized Mesenchymal Stem Cells (Y201 TERT-hMSCs) were found to favor the growth and differentiation of Y201 cells and promote calcium nodule formation. Overall, these surface coatings are promising candidates for delivering antimicrobial activity with bone-inducing functions for future bone tissue engineering applications.
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Miel , Ácido Hialurónico , Ácido Hialurónico/farmacología , Ácido Hialurónico/química , Escherichia coli , Óxido de Magnesio , Antibacterianos/farmacología , Antibacterianos/química , Colágeno/química , Staphylococcus epidermidis , Materiales Biocompatibles Revestidos/farmacología , Materiales Biocompatibles Revestidos/químicaRESUMEN
The objectives of this study were to propose a statistical model to predict the behaviour of the thickness of the uteroplacental junction as a function of the gestation period in female dogs and to determine the relationship between the thickness of the placenta and gestational age in healthy female dogs whose pregnancies had elapsed without maternal-fetal alterations. Eight Border Collie female dogs were selected, aged 3-6 (4.48 ± 0.89) and weighing 16-22 kg (19.06 ± 1.9 kg). Female dogs with gestational ages from 20 to 62 days were examined weekly using B-mode ultrasonography. Ultrasound measurements of the uteroplacental junction were organized into four distinct groups: GT1 (27-36 days of gestation), GT2 (37-46 days of gestation), GT3 (47-56 days of gestation) and GT4 (57-62 days of gestation). Based on multiple linear regression, a statistical model was proposed to predict the behaviour of the thickness of the uteroplacental junction (y) as a function of the length of gestation (x) in female dogs, where b0 is the intercept (linear coefficient) and bp is the slope of the predictors. The analysis relating GT, age and weight could predict placental thickness and resulted in a statistically significant model [F(1,28) = 153,736; p < .001; R2 = .846], but only that relating the length of pregnancy (ß = .92; t = 12.399; p < .001) predicted the thickness of the placenta according to the equation y = b0 + bp.x1 [(thickness in cm) = ß -0.3 + 0.019 × (gestation time in days)]. Only in GT4 was there no correlation between placentas within the same pregnancy (p > .05). Based on the close relationship between the development of the uteroplacental junction thickness during pregnancy and gestational age, it is possible to develop a new tool to complement gestational ultrasound evaluation in female dogs. This is important because it allows better placental evaluation in the search for significant alterations that could compromise maternal-fetal health.
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Feto , Placenta , Embarazo , Femenino , Perros , Animales , Edad Gestacional , Placenta/diagnóstico por imagen , UltrasonografíaRESUMEN
A 12-year-old Saanen goat presented with a history of hyporexia and sudden recumbency. Euthanasia was indicated due to suspicion of hepatic neoplasia associated with senility. Necropsy revealed generalized oedema and increased liver size and weight (33 × 38 × 17 cm and 10.6 kg, respectively), with a firm, multilobular mass. Fusiform to polygonal neoplastic cells, with marked pleomorphism, anisocytosis and anisokaryosis, were seen on histopathological examination of the hepatic mass. The neoplastic cells were immunohistochemically positive for alpha-smooth muscle actin and vimentin but immunonegative for pancytokeratin. The Ki-67 index was 18.8%. A poorly differentiated leiomyosarcoma was diagnosed on the basis of the gross, histopathological and immunohistochemical findings and should be included in the differential diagnosis of liver disease in goats.
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Enfermedades de las Cabras , Leiomiosarcoma , Neoplasias Hepáticas , Animales , Leiomiosarcoma/veterinaria , Cabras , Neoplasias Hepáticas/veterinariaRESUMEN
This study aimed to analyze effect of physical exercise in hemogasometric and electrolytic profiles of young Mangalarga Marchador horses beginning training for gait competitions. Six Mangalarga Marchador gaited horses with 6 months of training were evaluated. The ages ranged from three and a half to five years and included four stallions and two mares, with mean (±S.D.) body weight of 435±30Kg. Venous blood samples were collected from the horses, rectal temperature and HR were measured before and immediately after the gait test, and blood samples were used for hemogasometric and laboratory analyses. The Wilcoxon signed-rank test was used in the statistical analysis, assigning statistical significance for values of (p ≤ .05). Physical effort significantly affected HR (p ≤ .027), temperature (T) (p ≤ .028), oxygen pressure (pO2) (p ≤ .027), oxygen saturation (sO2) (p ≤ .046), calcium (Ca2+) (p ≤ .046), and glucose levels (GLI) (p ≤ .028). The heart rate, temperature, and pO2, sO2, Ca2+, and glucose levels were affected by exercise. There was no considerable dehydration in these horses, making it clear that, at this level of effort, they did not enter a state of, indicating that the animals, even young horses, were well conditioned to the submaximal effort required in gaiting tests. The horses showed good adaptation to exercise and did not enter a state of fatigue with the effort made, indicating that the animals in this study received adequate training and could perform the type of exercise proposed, characterized by a submaximal effort.
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Condicionamiento Físico Animal , Caballos , Animales , Femenino , Masculino , Peso Corporal , Marcha/fisiología , Frecuencia Cardíaca , GlucosaRESUMEN
Silver nanoparticles (AgNPs) represent one of the most commercialised metal nanomaterials, with an extensive number of applications that span from antimicrobial products to electronics. Bare AgNPs are very susceptible to aggregation, and capping agents are required for their protection and stabilisation. The capping agents can endow new characteristics which can either improve or deteriorate AgNPs (bio)activity. In the present work, five different capping agents were studied as stabilizing agents for AgNPs: trisodium citrate (citrate), polyvinylpyrrolidone (PVP), dextran (Dex), diethylaminoethyl-dextran (DexDEAE) and carboxymethyl-dextran (DexCM). The properties of the AgNPs were studied using a set of methods, including transmission electron microscopy, X-ray diffraction, thermogravimetric analysis and ultraviolet-visible and infrared spectroscopy. Coated and bare AgNPs were also tested against Escherichia coli, methicillin-resistance Staphylococcus aureus and Pseudomonas aeruginosa to analyse their capacity to suppress bacterial growth and eradicate biofilms of clinically relevant bacteria. The results showed that all the capping agents endow long-term stability for the AgNPs in water; however, when the AgNPs are in bacterial culture media, their stability is highly dependent on the capping agent properties due to the presence of electrolytes and charged macromolecules such as proteins. The results also showed that the capping agents have a substantial impact on the antibacterial activity of the AgNPs. The AgNPs coated with the Dex and DexCM were the most effective against the three strains, due to their better stability which resulted in the release of more silver ions, better interactions with the bacteria and diffusion into the biofilms. It is hypothesized that the antibacterial activity of capped AgNPs is governed by a balance between the AgNPs stability and their ability to release silver ions. Strong adsorption of capping agents like PVP on the AgNPs endows higher colloidal stability in culture media; however, it can decrease the rate of Ag+ release from the AgNPs and reduce the antibacterial performance. Overall, this work presents a comparative study between different capping agents on the properties and antibacterial activity of AgNPs, highlighting the importance of the capping agent in their stability and bioactivity.
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Anthocyanins from juçara fruits were extracted by pressurized liquid extraction (PLE) or ultrasound-assisted extraction (UAE), using aqueous solutions of 1,2-alkanediols and glycerol ethers as biobased solvents. The PLE (100 bar, 13 min, 1 mL/min flow rate) in the optimal extraction conditions originated 23.1 mganthocyanins·gdry biomass-1. On the other hand, the UAE was 10 min long, and the optimal conditions using 1,2-propanediol were 42.6 wt%, 160 W, and pH 7.0, leading to 50 mganthocyanins·gdry biomass-1. Extractions at the UAE optimized conditions, with aqueous solutions of five different 1,2-alkanediols and three glycerol ethers were performed, and compared to water and ethanolic extracts. The biobased solvent solutions presented anthocyanin yields up to 33% higher than water, and were shown to be as efficient as ethanol/water, but generated extracts with higher antioxidant capacity. The anthocyanin-rich extract of juçara, obtained with 1,2-propanediol, was used in the production of a natural soap and incorporated into a cream, showing that the addition of the juçara extract resulted in an antioxidant capacity in both products.
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Euterpe , Frutas , Frutas/química , Antocianinas , Antioxidantes/análisis , Propilenglicol , Solventes , Agua , Etanol , Extractos VegetalesRESUMEN
Five ternary copper(II) complexes, [Cu2(phen)2(L1)(ClO4)2] (1), [Cu2(phen)2(L1)(DMSO)2](PF6)2 (2), [Cu2(bpy)2(L1)(ClO4)2(H2O)2] (3), [Cu2(dmp)2(L1)(ClO4)2(H2O)2] (4), and [Cu(phen)(L2)]2(ClO4)2 (5), in which phen = 1,10-phenanthroline, bpy = 2,2'-bipyridine, dmp = 2,9-dimethyl-1,10-phenanthroline, H2L1 = 1,4-dihydroxyanthracene-9,10-dione and HL2 = 1-hydroxyanthracene-9,10-dione, DMSO = dimethylsulfoxide, were synthesized and fully characterized. Complex 2 was obtained through the substitution of perchlorate for DMSO. When two hydroxyquinone groups are present, L1 makes a bridge between two Cu(II) ions, which also bind two nitrogens of the respective diimine ligand. The compounds bind to calf thymus DNA and oxidatively cleave pUC19 DNA according to the following order of activity 1 > 4-5 > 3. Furthermore, complexes 1, 3, 4 and 5 inhibit topoisomerase-I activity and the growth of myelogenous leukemia cells with the IC50 values of 1.13, 10.60, 0.078, and 1.84 µmol L-1, respectively. Complexes 1 and 4 are the most active in cancer cells and in DNA cleavage.
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Cobre , Compuestos Heterocíclicos , Cobre/farmacología , Ligandos , Dimetilsulfóxido , Unión Proteica , Cristalografía por Rayos XRESUMEN
Valorisation of discarded kiwifruits is proposed by extracting bioactive compounds using sustainable solvents namely deep eutectic solvents (DES). A screening of fifteen DES and several hydrogen bonding donor solvents was carried out. Extraction efficiency was measured in terms of antioxidant activity using DPPH and FRAP tests. The influence of solvents characteristics in particular DES structure, presence of ethanol or water, and pH of DES/water mixture on the antioxidant properties of the extracts was studied. Results show that kiwi peels extracts obtained with DES based on carboxylic acids exhibit enhanced antioxidant activity compared to conventional solvents and alcohol-based DES with a maximum DPPH scavenging activity of 42.0 mg TE/g DW. Glycerol or ethylene glycol are also efficient at extracting antioxidant compounds with DPPH scavenging activity of 33.1 and 36.7 mg TE/g DW. Finally, a chemical analysis of extracts using HPTLC revealed that most active compounds extracted are polyphenolic compounds, presumably tannins.
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Antioxidantes , Frutas , Extractos Vegetales , Antioxidantes/química , Ácidos Carboxílicos , Etanol/química , Glicoles de Etileno , Glicerol , Extractos Vegetales/química , Solventes/química , Taninos/química , Agua/químicaRESUMEN
Silver nanoparticles (AgNPs) have found widespread commercial applications due to their unique physical and chemical properties. However, their relatively poor stability remains a main problem. An ideal way to improve the stability of AgNPs is not only to endow colloidal stability to individual nanoparticles but also to protect them from environmental factors that induce their agglomeration, like variation of ionic strength and pH, presence of macromolecules, etc. Mesoporous calcium carbonate vaterite crystals (CaCO3 vaterite) have recently attracted significant attention as inexpensive and biocompatible carriers for the encapsulation and controlled release of both drugs and nanoparticles. This work aimed to develop an approach to load AgNPs into CaCO3 vaterite without affecting their properties. We focused on improving the colloidal stability of AgNPs by using different capping agents, and understanding the mechanism behind AgNPs loading and release from CaCO3 crystals. Various methods were applied to study the AgNPs and CaCO3 crystals loaded with AgNPs (CaCO3/AgNPs hybrids), such as scanning and transmission electron microscopy, X-ray diffraction, infrared and mass spectrometry. The results demonstrated that polyvinylpyrrolidone and positively charged diethylaminoethyl-dextran can effectively keep the colloidal stability of AgNPs during co-precipitation with CaCO3 crystals. CaCO3/AgNPs hybrids composed of up to 4 % weight content of nanoparticles were produced, with the loading mechanism being well-described by the Langmuir adsorption model. In vitro release studies demonstrated a burst release of stable AgNPs at pH 5.0 and a sustained release at pH 7.5 and 9.0. The antibacterial studies showed that these hybrids are effective against Escherichia coli, methicillin-resistant Staphylococcus aureus and Pseudomonas aeruginosa, three important bacteria responsible for nosocomial infections. The developed approach opens a new way to stabilise, protect, store and release AgNPs in a controlled manner for their use as antimicrobial agents.
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Nanopartículas del Metal , Staphylococcus aureus Resistente a Meticilina , Plata/química , Nanopartículas del Metal/química , Carbonato de Calcio/química , Antibacterianos/farmacología , Antibacterianos/química , Escherichia coli , Pruebas de Sensibilidad MicrobianaRESUMEN
Detergent formulations for cleaning a carbonized soildegreaserstypically comprise surfactants, organic solvents, phosphate-based cleaning agents, and alkaline agents, which results in high pH values (>11) that raise human and environmental risks. It is important to develop eco-friendly and safer degreasers, while maintaining their cleaning efficiency. In this work, simple degreaser formulations, with a pH below 11 and without phosphates, were developed by using a mixture of solvent, surfactant, and water to remove carbonized soil. The efficiency of the new degreaser formulations (with 5 wt% solvent, 5 wt% nonionic or ionic surfactant, and 90 wt% water) was evaluated by an abrasion test in the removal of carbonized soil from ceramic and stainless steel surfaces and compared with a commercial product. The results obtained show that the formulations comprising isopropylene glycol (IPG) with C11−C13 9EOs and diethylene glycol butyl ether (BDG) with octyltrimethylammonium octanoate ([N1118][C8O2]) present the best cleaning efficiency for both surfaces. The composition of these formulations was optimized for each surface using a mixture design. The resulting formulations, despite having a simpler composition, a pH lower than 11, and being phosphate-free, presented a cleaning efficiency equal or slightly higher than the commercial control. These results show that it is possible to design degreasers that are much less aggressive to the environment and user, while simultaneously fulfilling the market requirements.
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Detergentes , Suelo , Humanos , Tensoactivos/química , Agua , SolventesRESUMEN
PLLA, PCL and PHBV are aliphatic polyesters which have been researched and used in a wide range of medical devices, and all three have advantages and disadvantages for specific applications. Blending of these materials is an attractive way to make a material which overcomes the limitations of the individual polymers. Both PCL and PHBV have been evaluated in polymer blends with PLLA in order to provide enhanced properties for specific applications. This paper explores the use of PCL and PHBV together with PLLA in ternary blends with assessment of the thermal, mechanical and processing properties of the resultant polymer blends, with the aim of producing new biomaterials for orthopaedic applications. DSC characterisation is used to demonstrate that the materials can be effectively blended. Blending PCL and PHBV in concentrations of 5-10% with PLLA produces materials with average modulus improved by up to 25%, average strength improved by up to 50% and average elongation at break improved by 4000%, depending on the concentrations of each polymer used. PHBV impacts most on the modulus and strength of the blends, whilst PCL has a greater impact on creep behaviour and viscosity. Blending PCL and PHBV with PLLA offers an effective approach to the development of new polyester-based biomaterials with combinations of mechanical properties which cannot be provided by any of the materials individually.
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Poliésteres , Polímeros , Materiales Biocompatibles , ViscosidadRESUMEN
Hydrogel-based bioinks are the main formulations used for Articular Cartilage (AC) regeneration due to their similarity to chondral tissue in terms of morphological and mechanical properties. However, the main challenge is to design and formulate bioinks able to allow reproducible additive manufacturing and fulfil the biological needs for the required tissue. In our work, we investigated an innovative Manuka honey (MH)-loaded photocurable gellan gum methacrylated (GGMA) bioink, encapsulating mesenchymal stem cells differentiated in chondrocytes (MSCs-C), to generate 3D bioprinted construct for AC studies. We demonstrated the beneficial effect of MH incorporation on the bioink printability, leading to the obtainment of a more homogenous filament extrusion and therefore a better printing resolution. Also, GGMA-MH formulation showed higher viscoelastic properties, presenting complex modulus G∗ values of â¼1042 âPa, compared to â¼730 âPa of GGMA. Finally, MH-enriched bioink induced a higher expression of chondrogenic markers col2a1 (14-fold), sox9 (3-fold) and acan (4-fold) and AC ECM main element production (proteoglycans and collagen).
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A 7-year-old female goat developed progressive ataxia, which progressed to sternal recumbency. Clinical examination revealed a slight elevation in the sacral spine (S1-S2), tetraparesis, perineal hypoaesthesia and absent tail and anal reflexes. Due to unresponsiveness to treatment with corticosteroids, the goat was euthanized. At necropsy, a 4.0 × 5.7 × 2.5 cm tumour mass was found in the uterine body and right uterine horn. In the cauda equina (L6âS2), a 3 cm tumour associated with a 2 cm ventral intraosseous sacral haematoma was also found. The tumours were characterized by neoplastic proliferation of columnar epithelial cells with a predominant tubular pattern. Neoplastic cells with glandular cytoplasm stained with acid Alcian blue and periodic acidâSchiff. Other metastases were found in the lungs, right ovary, dura mater and nerve roots of the medullary cone. Neoplastic cells were immunolabelled for cytokeratin but were negative for vimentin, and the tumour was diagnosed as metastatic endometrial tubular adenocarcinoma. To our knowledge, this is the first report of intramedullary metastasis to the spinal cord of this tumour in any species except humans.
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Adenocarcinoma , Carcinoma , Cauda Equina , Enfermedades de las Cabras , Neoplasias Uterinas , Adenocarcinoma/veterinaria , Animales , Carcinoma/veterinaria , Femenino , Cabras , Humanos , Neoplasias Uterinas/veterinariaRESUMEN
Inspired by the recently proposed cooperative mechanism of hydrotropy, where water molecules mediate the aggregation of hydrotrope around the solute, this work studies the impact of apolar volume and polar group position on the performance of hydrotropes. To do so, the ability of two different families of alkanediols (1,2-alkanediols and 1,n-alkanediols) to increase the aqueous solubility of syringic acid is initially investigated. Interestingly, it is observed that in the dilute region (low hydrotrope concentration), the relative position of the hydroxyl groups of the alkanediols does not impact their performance. Instead, their ability to increase the solubility of syringic acid correlates remarkably well with the size of their alkyl chains. However, this is not the case for larger hydrotrope concentrations, where 1,2-alkanediols are found to perform, in general, better than 1,n-alkanediols. These seemingly contradictory findings are reconciled using theoretical and experimental techniques, namely the cooperative model of hydrotropy and chemical environment probes (Kamlet-Taft and pyrene polarity scales). It is found that the number of hydrotropes aggregated around a solute molecule does not increase linearly with the apolar volume of the former, reaching a maximum instead. This maximum is discussed in terms of competing solute-hydrotrope and hydrotrope-hydrotrope interactions. The results suggest that hydrotrope self-aggregation is more prevalent in 1,n-alkanediols, which negatively impacts their performance as hydrotropes. The results reported in this work support the cooperative model of hydrotropy and, from an application perspective, show that hydrotropes should be designed taking into consideration not only their apolar volume but also their ability to stabilize their self-aggregation in water, which negatively impacts their performance as solubility enhancers.
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Agua , Solubilidad , Soluciones/química , Agua/químicaRESUMEN
DNA oxidation by ten-eleven translocation (TET) family enzymes is essential for epigenetic reprogramming. The conversion of 5-methylcytosine (5mC) into 5-hydroxymethylcytosine (5hmC) initiates developmental and cell-type-specific transcriptional programs through mechanisms that include changes in the chromatin structure. Here, we show that the presence of 5hmC in the transcribed gene promotes the annealing of the nascent RNA to the template DNA strand, leading to the formation of an R-loop. Depletion of TET enzymes reduced global R-loops in the absence of gene expression changes, whereas CRISPR-mediated tethering of TET to an active gene promoted the formation of R-loops. The genome-wide distribution of 5hmC and R-loops shows a positive correlation in mouse and human stem cells and overlap in half of all active genes. Moreover, R-loop resolution leads to differential expression of a subset of genes that are involved in crucial events during stem cell proliferation. Altogether, our data reveal that epigenetic reprogramming via TET activity promotes co-transcriptional R-loop formation, disclosing new mechanisms of gene expression regulation.
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Dioxigenasas , Estructuras R-Loop , 5-Metilcitosina/metabolismo , Animales , Citosina , ADN/metabolismo , Metilación de ADN , Dioxigenasas/genética , Epigénesis Genética , Epigenómica , Humanos , RatonesRESUMEN
The aim of the study was to correlate the spectral index of the right and left uterine arteries with equine placental development in mares with advanced pregnancies. We examined 32 multiparous Mangalarga Marchador mares with gestation of 150-240 days. During pregnancy, the pulsatility index (PI) and resistance index (RI) of the uterine arteries were obtained using spectral Doppler ultrasonography, and the combined uteroplacental thickness was obtained monthly using B-mode ultrasonography. The combined uteroplacental thickness correlated with gestational time of up to 13 years of age, and the significant difference was observed from the sixth month onwards. The CUPT stayed within the ideal measurements for this breed and for this gestational period. There was no correlation of CUPT with PI, however a negative and significant correlation of the RI was observed. The resistance index differed significantly among age groups, and the RI of the left uterine artery tended to decrease in all age groups. Furthermore, only RI differed significantly between the medians of gestatinal age. The left PI dropped in older mares. Thus, there an increased blood perfusion in the uterine arteries of mares with advanced pregnancies and among different age categories during placental and fetal physiological development.
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Placenta , Placentación , Animales , Femenino , Edad Gestacional , Caballos , Placenta/diagnóstico por imagen , Embarazo , Ultrasonografía , Ultrasonografía Doppler/veterinaria , Arteria Uterina/diagnóstico por imagen , Útero/diagnóstico por imagenRESUMEN
A new rutin copper(II) complex (R-Cu2) was prepared and characterized by spectroscopic methods and elemental analysis. The effects of rutin and R-Cu2 were evaluated on the prevention of hypercholesterolemia in animals feed with high-cholesterol diet (HCD) for 8 weeks. The animals (n = 5) were neither fed with HCD nor treated (control group), or were treated with vehicle, 10 mg/kg simvastatin, rutin (16 and 160 µmol/kg), and R-Cu2 (16 and 160 µmol/kg) administered orally. Total cholesterol (TC) levels were significantly increased (p < .01) in all HCD groups. In rutin and R-Cu2 groups, it was observed a discrete, but not significant, TC and LDL-induced increase inhibition compared with vehicle-treated group. R-Cu2 treatment significantly decreased (p < .05) plasma triglycerides compared with the vehicle-treated group. All groups receiving treatments maintained the malondialdehyde at normal levels. Serum NO levels were reduced in animals treated with rutin and R-Cu2 compared with the vehicle-treated group. In addition, the results also showed that the groups treated with rutin and R-Cu2 reduced significantly (p < .01), the number of neutrophils and prevented histological changes in all evaluated liver zones. R-Cu2 group maintained the ALT, AST, and ALP enzymes at normal levels. Thus, the effects of R-Cu2 in modulating inflammation and protecting liver damage were confirmed. PRACTICAL APPLICATIONS: Rutin, a plant-derived flavonoid, is one of phenolic compounds well known as a nutraceutical due to its antioxidant and anti-inflammatory properties. Findings of this study demonstrate the effects of both rutin and R-Cu2 in modulating inflammation and protecting liver damage in hypercholesterolemic rats. However, some effects analyzed became more evident in R-Cu2. Thereby, it was shown that the synthesis of a new flavonoid compound (R-Cu2) could be applied as a nutraceutical benefit option to prevent hypercholesterolemia condition.
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Enfermedad Hepática Inducida por Sustancias y Drogas , Hipercolesterolemia , Hepatopatías , Animales , Enfermedad Hepática Inducida por Sustancias y Drogas/tratamiento farmacológico , Enfermedad Hepática Inducida por Sustancias y Drogas/prevención & control , Colesterol , Hipercolesterolemia/tratamiento farmacológico , Inflamación , Peroxidación de Lípido , Ratas , Rutina/farmacologíaRESUMEN
Acute generalized exanthematous pustulosis (AGEP) is a rare entity characterized by fever associated with the sudden appearance of erythematous lesions, on which multiple sterile, non-follicular pustules develop. We describe a case of a 44-year-old healthy male who developed fever and multiple erythematous and edematous lesions with progressive generalization to the entire body, associated with multiple small non-follicular pustules three days after having started flucloxacillin for the treatment of a furuncle. Considering the characteristics of the exanthema, fever, and association with aminopenicillin initiation, AGEP was considered. A skin biopsy revealed subcorneal and superficial epidermal pustules, with foci of spongiosis, papillary edema, and a superficial, perivascular inflammatory cell infiltrate with neutrophils and eosinophils, consistent with the clinical diagnosis of AGEP. The culprit drug was suspended, and prednisolone was started, considering the rash extension, with progressive and complete improvement. Although it is a rare condition, the hypothesis of AGEP should be considered in acute febrile conditions with disseminated pustules. It resolves spontaneously after discontinuation of the offending drug, and the diagnosis is based on clinical presentation and skin biopsy.