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1.
Artículo en Inglés | MEDLINE | ID: mdl-38701833

RESUMEN

In this work we report magnetic properties of the orthorhombic perovskite Lu0.9Sr0.1Cr0.5Fe0.5O3 synthesized by a wet chemical method. As in LuCr0.5Fe0.5O3 the compound with Sr shows the magnetization reversal phenomenon, but the magnetic order and the compensation temperature occur at higher temperatures. Interestingly, in M vs H curves a hysteresis loop is observed when Cr4+ and Cr3+ ions coexist as a consequence of the aliovalent substitution of Lu3+ by Sr2+ in the B sites of the perovskite. To explain this behavior, we performed numerical simulations with a magnetic model for Lu1-xSrxCr0.5Fe0.5O3 perovskites with x=0 and x=0.1. We found that the ferromagnetic coupling of Fe3+ and Cr4+ through superexchange interactions (according the empiric Goodenough-Kanamori-Anderson rules, GKA) increases the magnetization at high fields and that the presence of ferromagnetic clusters explains the hysteretic behavior found in simulations.

2.
Hum Genomics ; 18(1): 29, 2024 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-38520002

RESUMEN

Chromosomal structural rearrangements consist of anomalies in genomic architecture that may or may not be associated with genetic material gain and loss. Evaluating the precise breakpoint is crucial from a diagnostic point of view, highlighting possible gene disruption and addressing to appropriate genotype-phenotype association. Structural rearrangements can either occur randomly within the genome or present with a recurrence, mainly due to peculiar genomic features of the surrounding regions. We report about three non-related individuals, harboring chromosomal structural rearrangements interrupting SETBP1, leading to gene haploinsufficiency. Two out of them resulted negative to Chromosomal Microarray Analysis (CMA), being the rearrangement balanced at a microarray resolution. The third one, presenting with a complex three-chromosome rearrangement, had been previously diagnosed with SETBP1 haploinsufficiency due to a partial gene deletion at one of the chromosomal breakpoints. We thoroughly characterized the rearrangements by means of Optical Genome Mapping (OGM) and Whole Genome Sequencing (WGS), providing details about the involved sequences and the underlying mechanisms. We propose structural variants as a recurrent event in SETBP1 haploinsufficiency, which may be overlooked by laboratory routine genomic analyses (CMA and Whole Exome Sequencing) or only partially determined when associated with genomic losses at breakpoints. We finally introduce a possible role of SETBP1 in a Noonan-like phenotype.


Asunto(s)
Aberraciones Cromosómicas , Haploinsuficiencia , Humanos , Haploinsuficiencia/genética , Reordenamiento Génico , Cromosomas , Secuenciación Completa del Genoma/métodos , Proteínas Portadoras/genética , Proteínas Nucleares/genética
3.
J Phys Condens Matter ; 36(1)2023 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-37703900

RESUMEN

The magnetization reversal (MR) of the layered Ni4-xZnxNb2O9ferrimagnetic compounds, withx=0,0.25,0.50and 0.75, is studied in this work using Monte Carlo (MC) simulations and mean field (MF) calculations. First, we analyze the parent compound to set the parameters of our simulations; testing together MC simulations, MF calculations, and MR experiments reported by Bollettaet al(2022J. Appl. Phys.132153901). Then using two different approaches we fit the MR curves of the series of compounds finding a quite good agreement between MC simulations and the experiments. According to these results, Zn substitutions change the relative contribution to the magnetization of the different layers. Here we present two possible hypotheses to explain this effect; one involving a heterogeneous distribution of Zn2+among the layers, and the other related to distortions of the NiO6octahedra.

5.
Basic Clin Pharmacol Toxicol ; 128(1): 91-102, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32780565

RESUMEN

Solidagenone (SOL) is a labdane-type diterpenoid found in Solidago chilensis, a plant traditionally used to treat skin diseases, kidney pain and ovarian inflammation. In this study, the topical anti-inflammatory activity of SOL was evaluated using in vivo and in silico assays. Croton oil-, arachidonic acid (AA)- and phenol-induced ear oedema mouse models were applied in the in vivo studies. Myeloperoxidase (MPO) and N-acetyl-ß-D-glucosaminidase (NAG) activities and tumour necrosis factor alpha (TNF-α), interleukin-6 (IL-6) and nitric oxide (NO) levels were determined, as well as histopathological analyses were conducted. Interaction profiles between SOL and cyclooxygenase-1 (COX-1), cyclooxygenase-2 (COX-2), glucocorticoid receptor, estradiol-17-ß-dehydrogenase and prostaglandin-E(2)-9-reductase were established using molecular docking. SOL significantly inhibited croton oil-, AA- and phenol-induced ear oedema (P < .001) at doses of 0.1, 0.5 and 1.0 mg/ear. The MPO and NAG activities and TNF-α, IL-6 and NO levels were decreased (P < .001). The histopathological data revealed that inflammatory parameters (oedema thickness, leucocyte infiltration and vasodilatation) were reduced by treatment with SOL at doses of 0.1, 0.5 and 1.0 mg/ear. The docking study showed that SOL interacts with COX-1 and prostaglandin-E(2)-9-reductase through hydrogen bonding, inhibiting these enzymes. These results indicate that SOL may be a promising compound for the treatment of cutaneous inflammatory disorders and has potential as a topical anti-inflammatory agent.


Asunto(s)
Inhibidores de la Ciclooxigenasa/farmacología , Dermatitis/prevención & control , Edema/prevención & control , Furanos/farmacología , Hidroxiprostaglandina Deshidrogenasas/antagonistas & inhibidores , Proteínas de la Membrana/antagonistas & inhibidores , Naftalenos/farmacología , Extractos Vegetales/farmacología , Piel/efectos de los fármacos , Solidago , Acetilglucosaminidasa/metabolismo , Animales , Ciclooxigenasa 1/metabolismo , Inhibidores de la Ciclooxigenasa/aislamiento & purificación , Inhibidores de la Ciclooxigenasa/metabolismo , Dermatitis/metabolismo , Dermatitis/patología , Modelos Animales de Enfermedad , Edema/inducido químicamente , Edema/metabolismo , Edema/patología , Furanos/aislamiento & purificación , Furanos/metabolismo , Enlace de Hidrógeno , Hidroxiprostaglandina Deshidrogenasas/metabolismo , Interleucina-6/metabolismo , Masculino , Proteínas de la Membrana/metabolismo , Ratones , Simulación del Acoplamiento Molecular , Naftalenos/aislamiento & purificación , Naftalenos/metabolismo , Óxido Nítrico/metabolismo , Peroxidasa/metabolismo , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/metabolismo , Unión Proteica , Transducción de Señal , Piel/metabolismo , Piel/patología , Solidago/química , Factor de Necrosis Tumoral alfa/metabolismo
7.
Mult Scler Relat Disord ; 38: 101871, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31786463

RESUMEN

BACKGROUND: Dimethyl-fumarate (DMF) was effective and safe in relapsing-remitting multiple sclerosis (MS) in randomized clinical trials. We aimed to evaluate the efficacy and safety of DMF and factors related to drug response in real-life setting. METHODS: We analysed prospectively collected demographic and clinical data for patients treated with DMF in six multiple sclerosis (MS) centers from 2015 to 2017 in Campania region, Italy. We performed univariate and multivariate analyses to assess relationships between baseline parameters and DMF efficacy outcomes, Annualized Relapse Rate (ARR), Expanded Disability Status Scale (EDSS) progression and No Evidence of Disease Activity (NEDA-3) status. RESULTS: we analyzed data of 456 patients (67% female subjects, mean age 40 ± 12 years, mean disease duration 9 ± 9 years, mean treatment duration 18 ± 11 months, median EDSS 2.5, 0-8). Proportion of Naïve versus pretreated with other DMTs patients was 149/307 (32.7%), with 122 patients switching to DMF for disease activity (26.7%) and 185 for safety and tolerability issues (40.6%). During treatment with DMF, the annualized relapse rate was reduced by 75% respect to the pre-treatment ARR [incidence-rate-ratio (IRR) = 0.25, p < 0.001, CI 0.18-0.33]. Factors influencing ARR rate while on DMF were relapsing remitting (RR) MS course (IRR = 2.0, p = <0.001, CI 1.51-2.73) and previous DMTs status: de-escalating from second-line therapies was associated to higher risk of relapsing (IRR = 1.8, p < 0.001, CI 1.39-2.31). At multivariable Cox proportional hazard model, only age of onset was related with rate or relapses, with younger age being protective (HR 0.96, p = 0,02). EDSS remained stable in 88% of patients. Disease duration was associated with higher rate of NEDA-3 failure, that was instead maintained in 65% of patients at 24 months. 109 patients (22%) discontinued therapy after a mean of 1.1 ±+ 0.7 years. Reasons for DMF discontinuation over time were lack of efficacy (50%), safety issues (30%), tolerability (7%), poor compliance (7%), and pregnancy (4%). Higher pre-treatment EDSS was associated with DMF discontinuation (p = 0.009). Only 33 patients dropped out due to safety reasons (7%), the most frequent safety issues driving to drop out being lymphopenia, liver/pancreatic enzymes increase, gatrointestinal severe tolerability issues. We recorded 95 cases (24%) of lymphopenia: 60 grade I (13%), 31 grade II (7%) and 4 grade III (1%). CONCLUSIONS: We confirm that DMF shows a good efficacy in both naïve patients and patients switching from other first-line DMTs, especially in patients with early onset of disease. Higher baseline EDSS was a risk factor for discontinuing DMF therapy, while shorter disease duration was protective for both EDSS progression and NEDA-3 status maintenance.


Asunto(s)
Dimetilfumarato/farmacología , Progresión de la Enfermedad , Factores Inmunológicos/farmacología , Esclerosis Múltiple Crónica Progresiva/tratamiento farmacológico , Esclerosis Múltiple Recurrente-Remitente/tratamiento farmacológico , Evaluación de Resultado en la Atención de Salud , Adulto , Edad de Inicio , Dimetilfumarato/efectos adversos , Femenino , Humanos , Factores Inmunológicos/efectos adversos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Recurrencia , Estudios Retrospectivos , Factores de Tiempo
8.
Phys Rev E ; 100(5-1): 052138, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31870025

RESUMEN

Evidence of critical dynamics has been found recently in both experiments and models of large-scale brain dynamics. The understanding of the nature and features of such a critical regime is hampered by the relatively small size of the available connectome, which prevents, among other things, the determination of its associated universality class. To circumvent that, here we study a neural model defined on a class of small-world networks that share some topological features with the human connectome. We find that varying the topological parameters can give rise to a scale-invariant behavior either belonging to the mean-field percolation universality class or having nonuniversal critical exponents. In addition, we find certain regions of the topological parameter space where the system presents a discontinuous, i.e., noncritical, dynamical phase transition into a percolated state. Overall, these results shed light on the interplay of dynamical and topological roots of the complex brain dynamics.

9.
Ann Hematol ; 97(9): 1717-1726, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29705860

RESUMEN

Infections by multidrug-resistant (MDR) bacteria are a worrisome phenomenon in hematological patients. Data on the incidence of MDR colonization and related bloodstream infections (BSIs) in haematological patients are scarce. A multicentric prospective observational study was planned in 18 haematological institutions during a 6-month period. All patients showing MDR rectal colonization as well as occurrence of BSI at admission were recorded. One-hundred forty-four patients with MDR colonization were observed (6.5% of 2226 admissions). Extended spectrum beta-lactamase (ESBL)-producing (ESBL-P) enterobacteria were observed in 64/144 patients, carbapenem-resistant (CR) Gram-negative bacteria in 85/144 and vancomycin-resistant enterococci (VREs) in 9/144. Overall, 37 MDR-colonized patients (25.7%) developed at least one BSI; 23 of them (62.2%, 16% of the whole series) developed BSI by the same pathogen (MDRrel BSI), with a rate of 15.6% (10/64) for ESBL-P enterobacteria, 14.1% (12/85) for CR Gram-negative bacteria and 11.1% (1/9) for VRE. In 20/23 cases, MDRrel BSI occurred during neutropenia. After a median follow-up of 80 days, 18 patients died (12.5%). The 3-month overall survival was significantly lower for patients colonized with CR Gram-negative bacteria (83.6%) and VRE (77.8%) in comparison with those colonized with ESBL-P enterobacteria (96.8%). CR-rel BSI and the presence of a urinary catheter were independent predictors of mortality. MDR rectal colonization occurs in 6.5% of haematological inpatients and predicts a 16% probability of MDRrel BSI, particularly during neutropenia, as well as a higher probability of unfavourable outcomes in CR-rel BSIs. Tailored empiric antibiotic treatment should be decided on the basis of colonization.


Asunto(s)
Bacteriemia/epidemiología , Infecciones Bacterianas/epidemiología , Farmacorresistencia Bacteriana Múltiple , Neoplasias Hematológicas/complicaciones , Neoplasias Hematológicas/epidemiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Bacteriemia/microbiología , Infecciones Bacterianas/sangre , Infecciones Bacterianas/complicaciones , Infecciones Bacterianas/microbiología , Infecciones Relacionadas con Catéteres/epidemiología , Niño , Preescolar , Femenino , Neoplasias Hematológicas/microbiología , Humanos , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Adulto Joven
10.
Phys Rev E ; 97(2-1): 022132, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29548251

RESUMEN

In this work we introduce a variant of the Yule-Simon model for preferential growth by incorporating a finite kernel to model the effects of bounded memory. We characterize the properties of the model combining analytical arguments with extensive numerical simulations. In particular, we analyze the lifetime and popularity distributions by mapping the model dynamics to corresponding Markov chains and branching processes, respectively. These distributions follow power laws with well-defined exponents that are within the range of the empirical data reported in ecologies. Interestingly, by varying the innovation rate, this simple out-of-equilibrium model exhibits many of the characteristics of a continuous phase transition and, around the critical point, it generates time series with power-law popularity, lifetime and interevent time distributions, and nontrivial temporal correlations, such as a bursty dynamics in analogy with the activity of solar flares. Our results suggest that an appropriate balance between innovation and oblivion rates could provide an explanatory framework for many of the properties commonly observed in many complex systems.

11.
Sci Rep ; 8(1): 363, 2018 01 10.
Artículo en Inglés | MEDLINE | ID: mdl-29321534

RESUMEN

Mitochondrial networks exhibit a variety of complex behaviors, including coordinated cell-wide oscillations of energy states as well as a phase transition (depolarization) in response to oxidative stress. Since functional and structural properties are often interwinded, here we characterized the structure of mitochondrial networks in mouse embryonic fibroblasts using network tools and percolation theory. Subsequently we perturbed the system either by promoting the fusion of mitochondrial segments or by inducing mitochondrial fission. Quantitative analysis of mitochondrial clusters revealed that structural parameters of healthy mitochondria laid in between the extremes of highly fragmented and completely fusioned networks. We confirmed our results by contrasting our empirical findings with the predictions of a recently described computational model of mitochondrial network emergence based on fission-fusion kinetics. Altogether these results offer not only an objective methodology to parametrize the complexity of this organelle but also support the idea that mitochondrial networks behave as critical systems and undergo structural phase transitions.


Asunto(s)
Mitocondrias/metabolismo , Dinámicas Mitocondriales , Modelos Biológicos , Algoritmos , Animales , Fibroblastos , Expresión Génica , Genes Reporteros , Ratones , Microscopía Fluorescente
12.
Inflammopharmacology ; 26(4): 1005-1016, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29138954

RESUMEN

Palicourea rigida Kunth is traditionally used for the treatment of skin diseases, kidney pains and ovarian inflammation. Based on these traditional uses, this study evaluated the topical anti-inflammatory activity of the ethanol extract from P. rigida leaves (EEPR) and identified bioactive compounds. Ear edema was induced in Swiss mice by the topical application of Croton oil, arachidonic acid, phenol and capsaicin. Histopathological analysis and myeloperoxidase and N-acetyl-ß-D-glucosaminidase activities were determined. EEPR was characterized by UHPLC-UV-MS HPLC and the isolated compound was identified through 1H and 13C nuclear magnetic resonance and mass fragmentation. Interaction profiles between quercetin 3-O-ß-D-glucoside and cyclooxygenase-1 and -2 were established by molecular docking. EEPR significantly inhibited ear edema induced by Croton oil (p < 0.001), arachidonic acid (p < 0.01), phenol (p < 0.001) and capsaicin (p < 0.01 or p < 0.001). Histopathological analysis showed a reduction of edema, inflammatory cell infiltration and vasodilation. Additionally, the myeloperoxidase and N-acetyl-ß-D-glucosaminidase activities were decreased (p < 0.001). From spectroscopic data, quercetin 3-O-ß-D-glucoside was the identified compound. This compound can to interact with cyclooxygenase-1 and -2 through van der Waals interactions and dipole-dipole and hydrogen bonding's, demonstrating inhibition of these enzymes. The results indicate that EEPR is a source of active compounds with topical anti-inflammatory activity, justifying the traditional use of P. rigida and showing that this species has a therapeutic potential to treat skin inflammatory processes.


Asunto(s)
Antiinflamatorios/farmacología , Edema/tratamiento farmacológico , Extractos Vegetales/farmacología , Rubiaceae/química , Administración Tópica , Animales , Antiinflamatorios/aislamiento & purificación , Cromatografía Líquida de Alta Presión/métodos , Modelos Animales de Enfermedad , Edema/patología , Inflamación/tratamiento farmacológico , Inflamación/patología , Masculino , Ratones , Simulación del Acoplamiento Molecular , Extractos Vegetales/química , Hojas de la Planta
13.
Sci Rep ; 7(1): 15186, 2017 11 09.
Artículo en Inglés | MEDLINE | ID: mdl-29123175

RESUMEN

Chess is an emblematic sport that stands out because of its age, popularity and complexity. It has served to study human behavior from the perspective of a wide number of disciplines, from cognitive skills such as memory and learning, to aspects like innovation and decision-making. Given that an extensive documentation of chess games played throughout history is available, it is possible to perform detailed and statistically significant studies about this sport. Here we use one of the most extensive chess databases in the world to construct two networks of chess players. One of the networks includes games that were played over-the-board and the other contains games played on the Internet. We study the main topological characteristics of the networks, such as degree distribution and correlations, transitivity and community structure. We complement the structural analysis by incorporating players' level of play as node metadata. Although both networks are topologically different, we show that in both cases players gather in communities according to their expertise and that an emergent rich-club structure, composed by the top-rated players, is also present.


Asunto(s)
Redes Comunitarias , Conducta Social , Deportes , Humanos , Metadatos
14.
Oncoimmunology ; 6(10): e1347742, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29123962

RESUMEN

γδ T cells usually infiltrate many different types of cancer, but it is unclear whether they inhibit or promote tumor progression. Moreover, properties of tumor-infiltrating γδ T cells and those in the corresponding normal tissue remain largely unknown. Here we have studied features of γδ T cells in colorectal cancer, normal colon tissue and peripheral blood, and correlated their levels with clinicopathologic hallmarks. Flow cytometry and transcriptome analyses showed that the tumor comprised a highly variable rate of TILs (5-90%) and 4% γδ T cells on average, with the majority expressing Vδ1. Most Vδ1 and Vδ2 T cells showed a predominant effector memory phenotype and had reduced production of IFN- Î³ which was likely due to yet unidentified inhibitory molecules present in cancer stem cell secretome. Transcriptome analyses revealed that patients containing abundant γδ T cells had significantly longer 5-year disease free survival rate, suggesting their efficacy in controlling tumor at very early stage.

15.
Transl Med UniSa ; 16: 24-29, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28775966

RESUMEN

Although there is evidence of a growing awareness of the problem, no official policy statements or regulatory guidelines on polypharmacy have been released up to date by Italian Health Authorities. Medication review, application of appropriateness criteria and computerized prescription support systems are all possible approaches in order to improve the quality of prescribing in older persons. More focused training courses on multimorbidity and polytherapy management are encouraged. Furthermore a multidisciplinary approach integrating different health care professionals (physicians, pharmacists, and nurses) may positively impact on reducing the sense of fear related to discontinue or substitute drugs prescribed by others; the fragmentation of therapy among different specialists; reducing costs; and improving adverse drug reaction detection and reporting. Aiming at achieving the individualized pharmacotherapy, a multidisciplinary approach starting with identification of patients and risk for drug-related problems, followed by medication review overtime and use of inappropriateness criteria, supported by computerized systems has been proposed.

16.
PLoS One ; 11(12): e0168213, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-28005922

RESUMEN

A series of recent works studying a database of chronologically sorted chess games-containing 1.4 million games played by humans between 1998 and 2007- have shown that the popularity distribution of chess game-lines follows a Zipf's law, and that time series inferred from the sequences of those game-lines exhibit long-range memory effects. The presence of Zipf's law together with long-range memory effects was observed in several systems, however, the simultaneous emergence of these two phenomena were always studied separately up to now. In this work, by making use of a variant of the Yule-Simon preferential growth model, introduced by Cattuto et al., we provide an explanation for the simultaneous emergence of Zipf's law and long-range correlations memory effects in a chess database. We find that Cattuto's Model (CM) is able to reproduce both, Zipf's law and the long-range correlations, including size-dependent scaling of the Hurst exponent for the corresponding time series. CM allows an explanation for the simultaneous emergence of these two phenomena via a preferential growth dynamics, including a memory kernel, in the popularity distribution of chess game-lines. This mechanism results in an aging process in the chess game-line choice as the database grows. Moreover, we find burstiness in the activity of subsets of the most active players, although the aggregated activity of the pool of players displays inter-event times without burstiness. We show that CM is not able to produce time series with bursty behavior providing evidence that burstiness is not required for the explanation of the long-range correlation effects in the chess database. Our results provide further evidence favoring the hypothesis that long-range correlations effects are a consequence of the aging of game-lines and not burstiness, and shed light on the mechanism that operates in the simultaneous emergence of Zipf's law and long-range correlations in a community of chess players.


Asunto(s)
Bases de Datos Factuales , Juegos Recreacionales , Memoria/fisiología , Modelos Estadísticos , Deportes , Algoritmos , Humanos , Procesos Mentales
17.
Int J Mol Sci ; 17(12)2016 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-27916942

RESUMEN

Vernonia polyanthes Less. (Asteraceae), popularly known as "assa-peixe", is a plant species used in Brazilian traditional medicine for the treatment of cutaneous damage, cicatrization, inflammation, and rheumatism. Based on these ethnopharmacological findings, the current study evaluated the topical anti-inflammatory effects of the hexane (HEVP) and ethyl acetate (EAEVP) extracts from V. polyanthes leaves in experimental models of skin inflammation. Chemical characterization was carried out by HPLC-UV/DAD analysis. Anti-inflammatory activity was evaluated using Croton oil-, arachidonic acid (AA)-, phenol-, ethyl phenylpropiolate (EPP)-, and capsaicin-induced ear edema models in mice. Histopathological evaluation and measurements of myeloperoxidase (MPO) and N-acetyl-ß-d-glucosaminidase (NAG) enzymes were also performed. Rutin, luteolin, and apigenin were identified in EAEVP. Topically applied HEVP and EAEVP significantly (p < 0.05, p < 0.01 or p < 0.001) reduced edema induced by five different irritants at the doses tested (0.1, 0.5 and 1.0 mg/ear). Histopathological analysis revealed a reduction of edema, inflammatory cell infiltration, and vasodilation. In addition, the enzymes activity (MPO and NAG) in the ear tissues was reduced by the topical treatment of HEVP and EAEVP (p < 0.05, p < 0.01 or p < 0.001). The results suggest that V. polyanthes leaves are effective against cutaneous damage, which support its traditional use and open up new possibilities for the treatment of skin disorders.


Asunto(s)
Inflamación/tratamiento farmacológico , Extractos Vegetales/administración & dosificación , Piel/efectos de los fármacos , Vernonia/química , Acetatos/química , Administración Tópica , Animales , Antiinflamatorios , Brasil , Hexanos/química , Humanos , Inflamación/patología , Medicina Tradicional , Ratones , Fitoterapia , Extractos Vegetales/química , Hojas de la Planta/química , Piel/patología
18.
J Phys Condens Matter ; 28(47): 476003, 2016 11 30.
Artículo en Inglés | MEDLINE | ID: mdl-27661565

RESUMEN

In this work, we have performed Monte Carlo simulations in a classical model for RFe1-x Cr x O3 with R = Y and Lu, comparing the numerical simulations with experiments and mean field calculations. In the analyzed compounds, the antisymmetric exchange or Dzyaloshinskii-Moriya (DM) interaction induced a weak ferromagnetism due to a canting of the antiferromagnetically ordered spins. This model is able to reproduce the magnetization reversal (MR) observed experimentally in a field cooling process for intermediate x values and the dependence with x of the critical temperatures. We also analyzed the conditions for the existence of MR in terms of the strength of DM interactions between Fe(3+) and Cr(3+) ions with the x values variations.

19.
An Acad Bras Cienc ; 88(3): 1471-1484, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27411067

RESUMEN

The present study was designed to investigate the antioxidant, antinociceptive and anti-inflammatory activities of the ethanol extract from Ageratum fastigiatum branches. Phytochemical screening and total phenol and flavonoid contents were determined. The antioxidant activity was assessed by 2,2-diphenyl-1-pycrilhydrazin (DPPH) and iron reducing power methods. The antinociceptive effect was evaluated using the acetic acid-induced writhing, formalin, hot plate and tail immersion assays; while the carrageenan-induced paw edema and pleurisy tests were performed to examine the anti-inflammatory activity against acute inflammation. The extract revealed the presence of flavonoids, tannins, coumarins, terpenes, sterols and saponins. Expressive levels of total phenols and flavonoids and a promising antioxidant effect were quantified. At the doses of 50, 100 and 200 mg/kg, the extract inhibited the writhing, reduced both phases of paw licking time and increased the reaction time on the hot plate. In the tail immersion test, the extract (50, 100 and 200 mg/kg) caused a significant inhibition of pain. In these doses, the paw edema, exudate volume and leucocyte mobilization were significantly reduced. These results suggest that A. fastigiatum can be an active source of substances with antioxidant, antinociceptive and anti-inflammatory activities, adding scientific support to the appropriate use in the Brazilian folk medicine.

20.
Int J Radiat Biol ; 91(11): 891-7, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26272641

RESUMEN

PURPOSE: To assess the effect of 950 MHz ultra-high-frequency electromagnetic radiation (UHF-EMR) on biomarkers of oxidative damage to DNA, proteins and lipids in the left cerebral cortex (LCC) and right cerebral cortex (RCC) of neonate and 6-day-old rats. MATERIALS AND METHODS: Twelve rats were equally divided into two groups as controls (CR) and exposed (ER), for each age (0 and 6 days). The LCC and RCC were examined in ER and CR after exposure. Radiation exposure lasted 30 min per day for up to 27 days (throughout pregnancy and 6 days postnatal). The specific absorption rate ranged from 1.32-1.14 W/kg. The damage to lipids, proteins and DNA was verified by thiobarbituric acid reactive substances, carbonylated proteins (CP) and comets, respectively. The concentration of glucose in the peripheral blood of the rats was measured by the Accu-Chek Active Kit due to increased CP in RCC. RESULTS: In neonates, no modification of the biomarkers tested was detected. On the other hand, there was an increase in the levels of CP in the RCC of the 6-day-old ER. Interestingly, the concentration of blood glucose was decreased in this group. CONCLUSIONS: Our results indicate that there is no genotoxicity and oxidative stress in neonates and 6 days rats. However, the RCC had the highest concentration of CP that do not seem to be a consequence of oxidative stress. This study is the first to demonstrate the use of UHF-EMR causes different damage responses to proteins in the LCC and RCC.


Asunto(s)
Envejecimiento/metabolismo , Corteza Cerebral/metabolismo , Corteza Cerebral/efectos de la radiación , Proteínas del Tejido Nervioso/metabolismo , Exposición a la Radiación , Especies Reactivas de Oxígeno/metabolismo , Animales , Relación Dosis-Respuesta a Droga , Campos Electromagnéticos , Femenino , Masculino , Microondas , Estrés Oxidativo/fisiología , Estrés Oxidativo/efectos de la radiación , Dosis de Radiación , Ratas
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