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Benign prostatic hyperplasia (BPH) is the most common adenoma in old men. Tomatoes are a rich source of bioactive compounds that, as well as selenium (Se), possess antioxidant and antiproliferative activity. The aim was to evaluate the therapeutic effect of Se in combination with a tomato extract in aged rats with BPH. Aged male Wistar rats were divided in the following groups (n = 10 rats/group): Control (C), BPH, BPH + Finasteride (BPH + F), BPH + Tomato Lipidic Extract (BPH + E), BPH + Selenium (BPH + S) and BPH plus E plus S (BPH + E + S). After 4 weeks of treatment, prostate weight, diuresis, antioxidants enzymes, prooxidants and inflammatory markers, growth factors and androgens were determined. BPH + E + S reduced prostate weight by 59.29% and inhibited growth by 99.35% compared to BPH + F which only decreased weight and inhibited growth by 15.31% and 57.54%, respectively. Prooxidant markers were higher with BPH + F (49.4% higher vs. BPH), but BPH + E + S decreased these markers (94.27% vs. BPH) and increased antioxidant activity. Finally, diuresis was higher with the BPH + E + S combination and markers of inflammation and growth factors were significantly lower with respect to BPH + F. Our findings provide a beneficial and protective therapeutic option of E + S directed against androgens, oxidative stress and inflammation that regulates cell proliferation in the prostate gland.
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PURPOSE: Evaluate the therapeutic effect of a tomato lipidic extract (STE) in combination with selenium (Se) on rats with prostatic hyperplasia (PH) and to observe its possible mechanisms of action and synergism versus finasteride. MATERIALS AND METHODS: 54 male Wistar rats of nine weeks old were divided in Control (C), PH, Finasteride (F), STE, Se, F + STE, F + Se, STE + Se and F + STE + Se with testosterone enanthate (except C). After 4 weeks of treatment administration, prostate weight, bladder weight, diuresis, prooxidant and antioxidant activity, dihydrotestosterone (DHT), androgen receptor (AR) expression and anatomopathological analysis were determined. RESULTS: STE + Se decreased prostate weight 53.8% versus 28% in F group, also STE + Se decreased significatively glandular hyperplasia, prooxidant activity, DHT and AR expression and increased diuresis and antioxidant activity versus finasteride which increased MDA in prostate. CONCLUSIONS: These results demonstrate a greater therapeutic and beneficial effect of tomato lipidic extract in combination with Se in young rats with PH with respect to finasteride without increase prooxidant activity.
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Hiperplasia Prostática , Selenio , Solanum lycopersicum , Animales , Masculino , Ratas , Andrógenos/metabolismo , Antioxidantes/farmacología , Antioxidantes/uso terapéutico , Dihidrotestosterona/metabolismo , Finasterida/farmacología , Finasterida/uso terapéutico , Hiperplasia Prostática/tratamiento farmacológico , Hiperplasia Prostática/patología , Ratas Wistar , Receptores Androgénicos/metabolismo , Selenio/farmacología , Selenio/uso terapéutico , Testosterona/uso terapéuticoRESUMEN
High nitrogen compounds find wide use in the development of new propellants and explosives as well as pharmaceutical chemistry as bioisosteres, bacterial stains, and antifungal agents. A class of underexplored high-nitrogen materials includes azidoximes and their 1-hydroxytetrazole isomers. Azidoximes possess an energetic azide group and are quite sensitive to impact, spark, and friction. Therefore, these materials are generated in situ and cyclized under mild acidic conditions to their 1-hydroxytetrazole isomers. Recently, we synthesized a novel 1,2,4-triazine-derived azidoxime; however, upon subjecting this material to established cyclization conditions, no reaction was observed, even after prolonged reaction times with heating. Additional 1,2,4-triazine-derived azidoximes also displayed a similar lack of reactivities. This observation led us to probe the reactivity of these materials with both a DFT investigation and crystallographically based electrostatic potential mapping. In all, the lack of reactivity toward cyclization was found to be due to an inability of 1,2,4-triazine-based azidoximes to isomerize into the reactive (E)-conformation, requiring an activation energy of 26.4 kcal mol-1.
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Obesity increases the risk of arterial hypertension in young adults and favors an early-onset cardiomyopathy by generating oxidative stress. In this sense, indiscriminate consumption of sucrose and fructose sweetened beverages from early ages causes obesity, however its consequences on the heart when there is a genetic predisposition to develop hypertension are not clear. We compared the effects of sucrose, fructose, and their combination in weanling male spontaneously hypertensive rats to determine the relationship between genetic hypertension, obesity, and consumption of these sugars on the degree of cardiac hypertrophy, oxidative stress and Ca2+/calmodulin dependent protein kinase II delta oxidation. Histological, biochemical, and Western blot studies were performed 12 weeks after treatment initiation. We found that chronic consumption of sucrose or fructose leads to obesity, exacerbates genetic arterial hypertension-induced metabolic alterations, and increases cardiac oxidative stress, Ca2+/calmodulin dependent protein kinase II delta oxidation and cardiac hypertrophy. Nonetheless, when sucrose and fructose are consumed together, metabolic alterations worsen and are accompanied by dilated cardiomyopathy. These data suggest that sucrose and fructose combined consumption starting from maternal weaning in rats with genetic predisposition to arterial hypertension accelerates the progression of cardiomyopathy resulting in an early dilated cardiomyopathy.
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The prevalence of the metabolic syndrome (MetS) and its cardiac comorbidities as cardiac hypertrophy (CH) have increased considerably due to the high consumption of carbohydrates, such as sucrose and/or fructose. We compared the effects of sucrose (S), fructose (F) and their combination (S + F) on the development of MetS in weaned male Wistar rats and established the relationship between the consumption of these sugars and the degree of cardiac CH development, oxidative stress (OS) and Calcium/calmodulin-dependent protein kinase type II subunit delta oxidation (ox-CaMKIIδ). 12 weeks after the beginning of treatments with S, F or S + F, arterial pressure was measured and 8 weeks later (to complete 20 weeks) the animals were sacrificed and blood samples, visceral adipose tissue and hearts were obtained. Biochemical parameters were determined in serum and cardiac tissue to evaluate the development of MetS and OS. To evaluate CH, atrial natriuretic peptide (ANP), CaMKIIδ and ox-CaMKIIδ were determined by western blot and histological studies were performed in cardiac tissue. Our data showed that chronic consumption of S + F exacerbates MetS-induced CH which is related with a higher OS and ox-CaMKIIδ.
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Proteína Quinasa Tipo 2 Dependiente de Calcio Calmodulina/metabolismo , Cardiomegalia/enzimología , Carbohidratos de la Dieta/efectos adversos , Fructosa/efectos adversos , Síndrome Metabólico/enzimología , Miocardio/enzimología , Estrés Oxidativo/efectos de los fármacos , Sacarosa/efectos adversos , Animales , Carbohidratos de la Dieta/farmacología , Fructosa/farmacología , Masculino , Oxidación-Reducción/efectos de los fármacos , Ratas , Ratas Wistar , Sacarosa/farmacologíaRESUMEN
We have previously demonstrated that in the context of two-dimensional (2D) coherent electronic spectroscopy measured by phase modulation and phase-sensitive detection, an incoherent nonlinear response due to pairs of photoexcitations produced via linear excitation pathways contributes to the measured signal as an unexpected background [Grégoire et al., J. Chem. Phys. 147, 114201 (2017)]. Here, we simulate the effect of such incoherent population mixing in the photocurrent signal collected from a GaAs solar cell by acting externally on the transimpedance amplifier circuit used for phase-sensitive detection, and we identify an effective strategy to recognize the presence of incoherent population mixing in 2D data. While we find that incoherent mixing is reflected by the crosstalk between the linear amplitudes at the two time-delay variables in the four-pulse excitation sequence, we do not observe any strict phase correlations between the coherent and incoherent contributions, as expected from modeling of a simple system.
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We combine ultrafast electron diffraction and time-resolved terahertz spectroscopy measurements to link structure and electronic transport properties during the photoinduced insulator-metal transitions in vanadium dioxide. We determine the structure of the metastable monoclinic metal phase, which exhibits antiferroelectric charge order arising from a thermally activated, orbital-selective phase transition in the electron system. The relative contribution of the photoinduced monoclinic and rutile metals to the time-dependent and pump-fluence-dependent multiphase character of the film is established, as is the respective impact of these two distinct phase transitions on the observed changes in terahertz conductivity. Our results represent an important example of how light can control the properties of strongly correlated materials and demonstrate that multimodal experiments are essential when seeking a detailed connection between ultrafast changes in optical-electronic properties and lattice structure.
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PURPOSE: The impact of onabotulinum toxin type A (BoNT-A) on bladder afferent nerve pathways and chemosensory functions is an active area of investigation. There may be a role for BoNT-A in disorders of the ureter; however, no histologic studies have assessed the effects of BoNT-A on ureteral tissue. Our objective was to develop an animal model of ureteral inflammation and determine the impact of ureteral BoNT-A instillation on known mechanisms of inflammation. METHODS: The safety and feasibility of a novel animal model of ureteral inflammation was assessed. Through open cystotomy, the effect of ureteral BoNT-A instillation on inflammation was determined through H&E, masson's trichrome, Ki-67 stain, and prostaglandin E (PGE) synthase expression, a known marker of pain and inflammation in ureteral tissue. Urothelial microstructure was assessed using electron microscopy and standard histologic techniques. RESULTS: All experiments were carried to completion, and no systemic signs of botulinum toxicity were seen. BoNT-A exposure was associated with a decrease in PGE synthase expression in a dose-dependent fashion. BoNT-A exposure was not found to impact collagen deposition or cell proliferation. Disruption of tight junctions between urothelial cells was observed under conditions of inflammation. CONCLUSION: We describe the feasibility of a novel in vivo model of ureteral inflammation and report the first histologic study of the effects of BoNT-A on the ureter. Preliminary findings show that BoNT-A attenuates ureteral PGE synthase expression under conditions of inflammation. The application of BoNT-A may provide anti-inflammatory and analgesic effects in the context of ureteral disorders.
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Inhibidores de la Liberación de Acetilcolina/efectos adversos , Toxinas Botulínicas Tipo A/efectos adversos , Inflamación/inducido químicamente , Enfermedades Ureterales/inducido químicamente , Animales , Modelos Animales de Enfermedad , Estudios de Factibilidad , Femenino , Inflamación/patología , Masculino , Conejos , Enfermedades Ureterales/patologíaRESUMEN
Spin crossover complexes are known to undergo bond length, volume, and enthalpy changes during spin transition. In an explosive spin crossover complex, these changes could affect the mechanical and initiation sensitivity of the explosive and lead to the development of a new class of sensitivity switchable materials. To explore this relationship, the well-known spin crossover compound [Fe(Htrz)3]n[ClO4]2n (1) was re-evaluated for its explosive properties, and its mechanical impact sensitivity was correlated to spin transition. A variable temperature impact test was developed and used to evaluate the impact sensitivity of 1 in the low spin (LS, S = 0), thermally accessed high spin (HS, S = 2), and mixed LS and HS states. For comparison, the structurally similar Ni compound, [Ni(Htrz)3]n[ClO4]2n (2), which does not undergo a spin transition at accessible temperatures, was synthesized and characterized, and its explosive properties and variable temperature impact sensitivity measured. These results reveal a correlation between impact sensitivity and spin transition, where 1 exhibits lower impact sensitivity in the LS state and increases in sensitivity upon transition to the HS state. Density functional theory was used to predict structural changes that occur upon spin transition that correlate to the change in sensitivity. This demonstrates, for the first time, an explosive spin crossover compound (ExSCO) that exhibits switchable impact sensitivity with a fully reversible internal switching mechanism.
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Hybrid organic-inorganic semiconductors feature complex lattice dynamics due to the ionic character of the crystal and the softness arising from non-covalent bonds between molecular moieties and the inorganic network. Here we establish that such dynamic structural complexity in a prototypical two-dimensional lead iodide perovskite gives rise to the coexistence of diverse excitonic resonances, each with a distinct degree of polaronic character. By means of high-resolution resonant impulsive stimulated Raman spectroscopy, we identify vibrational wavepacket dynamics that evolve along different configurational coordinates for distinct excitons and photocarriers. Employing density functional theory calculations, we assign the observed coherent vibrational modes to various low-frequency (â²50 cm-1) optical phonons involving motion in the lead iodide layers. We thus conclude that different excitons induce specific lattice reorganizations, which are signatures of polaronic binding. This insight into the energetic/configurational landscape involving globally neutral primary photoexcitations may be relevant to a broader class of emerging hybrid semiconductor materials.
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In the version of this Article originally published, the units of the Fig. 3a x axis were incorrectly given as meV. They should have been eV. This has now been corrected in all versions of the Article.
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Understanding the factors that affect explosive sensitivity is paramount to the safe handling and development of new explosives molecules. Erythritol tetranitrate (ETN) is an explosive that recently has attracted significant attention in the explosives community because of its ease of synthesis and physical properties. Herein, we report the synthesis of ETN derivatives using azide, nitramine, and nitrate ester functional groups. Impact, spark, and friction sensitivity measurements, computationally calculated explosive properties, and the crystal structure analysis of the ETN derivatives are reported. Mixing explosive functional groups led to changes in the explosive sensitivity, explosive performance as well as physical properties including melting point and physical state at room temperature. Overall, we have demonstrated that combining functional groups can enable the tuning of explosive and physical properties of a molecule. This tunability can potentially aid in the development of new explosives in which characteristics are varied to meet certain specifications.
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Metal nitrides are strong refractory ceramic materials known for applications in the coatings, catalysis, and semiconductor industries. Lanthanide nitrides are difficult to prepare in high purity and often require high temperatures and sophisticated equipment. In this work, we present an approach to the synthesis of high-purity f-element nitrides through the use of simple lanthanide salts and the nitrogen-rich ligand 5,5'-bis(1H-tetrazolyl)amine (H2BTA) to form lanthanide complexes of 5,5'-bis(tetrazolato)amine (BTA2-). We have demonstrated that, when dehydrated, these types of complexes undergo a self-sustained combustion reaction under an inert atmosphere to yield nanostructured f-element nitride foams for lanthanum and cerium. The synthesis, characterization, and single-crystal X-ray crystallography of the BTA2- complexes of lanthanum, cerium, praseodymium, neodymium, and europium are also discussed.
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BACKGROUND: The aim of this study was to evaluate the effects of capsaicin (Cap), moderate exercise (Ex), and their combination on arterial blood pressure (BP) and metabolic complications in hypoestrogenic (HE) obese (HEOb) rats. Female Wistar rats were ovariectomized and given 300 g L-1 sucrose solution (HEOb), or purified water (HE) ad libitum, for 28 weeks. After shaving the abdominal skin, cold cream vehicle was applied to sedentary (Sed) and exercise (Ex) groups, and 0.75 g kg-1 Cap cream was applied to Ex groups. Ex groups ran on a treadmill every day for 20 min at speeds from 0.15 to 0.3 m s-1 . For combination groups (Cap + Ex), topical Cap was applied 90 min before Ex. The treatments were performed for 6 weeks, and BP was recorded before and at the end of the experimental protocol. The animals were killed by decapitation, and blood and tissues were obtained to perform oxidative profile, as well as to undertake biochemical and histologic studies. RESULTS: Compared with individual treatments, the combined therapy (Cap + Ex) in HEOb rats caused a higher reduction in the caloric intake, body weight, abdominal fat percentage, oxidative stress, and hepatic steatosis. In HEOb groups, Cap was the only treatment that reduced BP and prevented dyslipidemia and oxidative stress. CONCLUSION: The present data show that Cap improves the metabolic alterations induced by obesity and hypoestrogenism, suggesting that Cap can be considered as an excellent candidate for therapy of these clinical conditions. © 2020 Society of Chemical Industry.
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Capsaicina/administración & dosificación , Dislipidemias/prevención & control , Estrógenos/sangre , Terapia por Ejercicio , Hígado Graso/prevención & control , Obesidad/complicaciones , Obesidad/terapia , Animales , Presión Sanguínea/efectos de los fármacos , Terapia Combinada , Femenino , Humanos , Masculino , Obesidad/sangre , Obesidad/tratamiento farmacológico , Ratas , Ratas Wistar , Crema para la Piel/administración & dosificaciónRESUMEN
The reaction of 3,4-dinitropyrazole, 5-nitrotetrazole, or 4-nitro-1,2,3-triazole with 1,2,4,5-tetrazines substituted with 3,5-dimethylpyrazolyl (dmp) groups results in energetic cocrystals after 1 minute of reflux and cooling to room temperature in yields of 89-92 %. Hydrogen-bonding between the dmp group to the N-H of the energetic heterocycles are the predominant interaction that stabilizes the new cocrystals. Each cocrystal packs in a different lattice structure and the cocrystals with sheet-like and herring-bone crystal packing orientations are less sensitive than the cocrystal with the interlocked structure. Electrostatic potential mapping helps rationalize why dmp-substituted tetrazines readily form cocrystals, whereas more electron-deficient pyrazolyl tetrazines do not. The calculated energetic performance of the new cocrystals approaches that of 2,4,6-trinitrotoluene (TNT) and importantly, these materials will aid in the rational design of new cocrystalline energetic materials.
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The synthesis and characterization of new 1,2,4-triazolyl and 4-nitro-pyrazolyl substituted tetrazine ligands has been achieved. The strongly electron deficient 1,2,4-triazolyl substituted ligands did not coordinate Fe(II) metal centers, while the mildly electron deficient 4-nitro-pyrazolyl substituted ligands did coordinate Fe(II) metal centers in a 2:1 ratio of ligand to metal. The thermal stability and mechanical sensitivity characteristics of the complexes are similar to the conventional explosive pentaerythritol tetranitrate. The complexes had strong absorption in the visible region of the spectrum that extended into the near-infrared. In spite of having improved oxygen balances, increased mechanical sensitivity, and similar absorption of NIR light to recently reported Fe(II) tetrazine complexes, these newly synthesized explosives were more difficult to initiate with Nd:YAG pulsed laser light. Specifically, the complexes required lower densities (0.9 g/cm3) to initiate at the same threshold utilized to initiate previous materials at higher densities (1.05 g/cm3).
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Conjugated energetic molecules (CEMs) are a class of explosives with high nitrogen content that posses both enhanced safety and energetic performance properties and are ideal for direct optical initiation. As isolated molecules, they absorb within the range of conventional lasers. Crystalline CEMs are used in practice, however, and their properties can differ due to intermolecular interaction. Herein, time-dependent density functional theory was used to investigate one-photon absorption (OPA) and two-photon absorption (TPA) of monomers and dimers obtained from experimentally determined crystal structures of CEMs. OPA scales linearly with the number of chromophore units, while TPA scales nonlinearly, where a more than 3-fold enhancement in peak intensity, per chromophore unit, is calculated. Cooperative enhancement depends on electronic delocalization spanning both chromophore units. An increase in sensitivity to nonlinear laser initiation makes these materials suitable for practical use. This is the first study predicting a cooperative enhancement of the nonlinear optical response in energetic materials composed of relatively small molecules. The proposed model quantum chemistry is validated by comparison to crystal structure geometries and the optical absorption of these materials dissolved in solution.
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This study presents the synthesis and characterization of the oxidation products of 3,6-diazido-1,2,4,5-tetrazine (1) and 6-amino-[1,5-b]tetrazolo-1,2,4,5-tetrazine (2). 3,6-Diazido-1,2,4,5-tetrazine-1,4-dioxide was produced from oxidation with peroxytrifluoroacetic acid, and more effectively using hypofluorous acid, and 2 can be oxidized to two different products, 6-amino-[1,5-b]tetrazolo-1,2,4,5-tetrazine mono-N-oxide and di-N-oxide. These N-oxide compounds display promising performance properties as energetic materials.
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The synthesis and characterization of air stable Fe(II) coordination complexes with tetrazine and triazolo-tetrazine ligands and perchlorate counteranions have been achieved. Time-dependent density functional theory (TD-DFT) was used to model the structural, electrochemical, and optical properties of these materials. These compounds are secondary explosives that can be initiated with Nd:YAG laser light at lower energy thresholds than those of PETN. Furthermore, these Fe(II) tetrazine complexes have significantly lower sensitivity than PETN toward mechanical stimuli such as impact and friction. The lower threshold for laser initiation was achieved by altering the electronic properties of the ligand scaffold to tune the metal ligand charge transfer (MLCT) bands of these materials from the visible into the near-infrared region of the electromagnetic spectrum. Unprecedented decrease in both the laser initiation threshold and the mechanical sensitivity makes these materials the first explosives that are both safer to handle and easier to initiate than PETN with NIR lasers.
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We have prepared energetic nitrate ester derivatives of 1,2,4,5-tetrazine and 1,2,4-triazolo[4,3-b]-[1,2,4,5]-tetrazine ring systems as model compounds to study the electrochemical behavior of tetrazines in the presence of explosive groups. The model compounds showed lower thermal stabilities relative to PETN (pentaerythritol tetranitrate), but slightly improved mechanical sensitivities. The presence of electron-rich amine donors leads to a cathodic shift of the tetrazine redox potentials relative to those of previously reported tetrazine explosives. At these potentials, electron-rich tetrazines with either covalently bound or co-dissolved nitrate ester groups are irreversibly reduced. Effectively, changes in the electronic structure of tetrazines affect their electrochemical response to the presence of nitrate ester groups. Thus, it may be possible to develop tetrazine-based electrochemical sensors for the detection of specific explosives and electrocatalysts for their disposal.