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1.
Phys Chem Chem Phys ; 25(40): 27181-27188, 2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37789761

RESUMO

The two-dimensional (2D) metallic phase of MoS2, 1T-MoS2, has extraordinary electrical conductivity in contrast to the common 2D semiconducting phase, 2H-MoS2. However, the thermodynamic instabilities of 1T-MoS2 hinder its application. In this work, we investigate the possibilities of stabilizing 1T-MoS2 through heterostructure design using first-principles calculations. We found that MXene-based heterostructures could hamper phase transitions from 1T-MoS2 to 2H-MoS2 enabled by a larger phase transition kinetic energy barrier. Based on this finding, we propose a general and effective strategy for stabilizing 1T-MoS2, that is, building heterostructures using 1T-MoS2 and oxygen-functionalized MXenes. Besides, we have also observed that due to the occurrence of electron transfer in the heterostructure, 1T-MoS2 in the heterostructure exhibits improved hydrogen adsorption free energy and more active sites compared to the monolayer 1T-MoS2. These findings provide guidance for promoting and developing 1T-MoS2 for practical applications. In addition, the proposed heterostructure design strategy could inspire the study of phase transition behaviors and electrochemical properties of materials using interfaces.

2.
Angew Chem Int Ed Engl ; 62(32): e202304205, 2023 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-37313787

RESUMO

MXenes are 2D materials with great potential in various applications. However, the degradation of MXenes in humid environments has become a main obstacle in their practical use. Here we combine deep neural networks and an active learning scheme to develop a neural network potential (NNP) for aqueous MXene systems with ab initio precision but low cost. The oxidation behaviors of super large aqueous MXene systems are investigated systematically at nanosecond timescales for the first time. The oxidation process of MXenes is clearly displayed at the atomic level. Free protons and oxides greatly inhibit subsequent oxidation reactions, leading to the degree of oxidation of MXenes to exponentially decay with time, which is consistent with the oxidation rate of MXenes measured experimentally. Importantly, this computational study represents the first exploration of the kinetic process of oxidation of super-sized aqueous MXene systems. It opens a promising avenue for the future development of effective protection strategies aimed at controlling the stability of MXenes.

3.
J Stroke Cerebrovasc Dis ; 31(10): 106730, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36029688

RESUMO

OBJECTIVE: There is a low incidence of the medullary infarctions and sparse data about the vascular territories, as well as a correlation among the anatomic, magnetic resonance imaging (MRI) and neurologic signs. MATERIALS AND METHODS: Arteries of the 10 right and left sides of the brain stem were injected with India ink, fixed in formalin and microdissected. The enrolled 34 patients with medullary infarctions underwent a neurologic, MRI and Doppler examination. RESULTS: Four types of the infarctions were distinguished according to the involved vascular territories. The isolated medial medullary infarctions (MMIs) were present in 14.7%. The complete MMIs comprised one bilateral infarction (2.9%), whilst the incomplete and partial MMIs were observed in 5.9% and 8.9%, respectively. The anterolateral infarctions (ALMIs) were very rare (2.9%). The complete and incomplete lateral infarctions (LMIs), noted in 35.3%, comprised 11.8% and 23.6%, respectively, that is, the anterior (5.9%), posterior (8.9%), deep (2.9%), and peripheral (5.9%). Dorsal ischemic lesions (DMIs) occurred in 11.8%, either as a complete (2.9%), or isolated lateral (5.9%) or medial infarctions (2.9%). The remaining ischemic regions belonged to various combined infarctions of the MMI, ALMI, LMI and DMI (35.3%). The infarctions most often affected the upper medulla (47.1%), middle (11.8%), or both (29.5%). Several motor and sensory signs were manifested following infarctions, including vestibular, cerebellar, ocular, sympathetic, respiratory and auditory symptoms. CONCLUSIONS: There was a good correlation among the vascular territories, MRI ischemia features, and neurologic findings regarding the medullary infarctions.


Assuntos
Infartos do Tronco Encefálico , Infartos do Tronco Encefálico/etiologia , Cerebelo/irrigação sanguínea , Formaldeído , Humanos , Imageamento por Ressonância Magnética/efeitos adversos , Bulbo/irrigação sanguínea , Bulbo/diagnóstico por imagem
4.
Faraday Discuss ; 229: 75-88, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33889883

RESUMO

The activity-stability conundrum has long been the Achilles' heel in the design of catalysts, in particular, for electrochemical reactions such as water splitting. Here, we use ab initio thermodynamics to delineate the surface stoichiometry of a group of perovskite oxides with different activities towards the oxygen evolution reaction (OER), in order to get a measure of their stability under OER operating conditions. In particular, we compare the surface stability of SrIrO3, SrRuO3 and SrTiO3, establishing atomistic insights into the stability and dissolution of these oxide surfaces.

5.
Dermatol Ther ; 33(2): e13215, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31891450

RESUMO

Vitiligo is a relatively common disorder characterized by areas of depigmented skin. It may be associated with social stigma and adversely affects the quality of life. Although many treatment options are available, none is curable. The search continues for an effective therapeutic option. New targeted options include biologics and other immunomodulatory agents, with varying degrees of evidence. We have discussed briefly the therapeutic options with special emphasis on the newer immunomodulatory agents. We undertook a comprehensive English literature search across multiple databases such as PubMed, SCOPUS, EMBASE, MEDLINE, and Cochrane using keywords (alone and in combination) and MeSH items such as "vitiligo," "treatment," "recent," and "immunomodulators" to obtain several relevant articles, priority being given to prospective randomized controlled trials. We scanned all the relevant articles and summarized them to obtain the latest information about the treatment of this condition to prepare the current article.


Assuntos
Vitiligo , Humanos , Fatores Imunológicos/uso terapêutico , Terapia PUVA , Estudos Prospectivos , Qualidade de Vida , Vitiligo/diagnóstico , Vitiligo/terapia
6.
Dermatol Ther ; 33(1): e13175, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31758835

RESUMO

Numerous studies have demonstrated that the pigmentation of iris and around the eyelid is a common side effect of latanoprost, a prostaglandin F2alpha analogue used in the treatment of glaucoma. Hence, the authors decided to study the effectiveness of topical latanoprost on vitiligo patches around the eyelid. In this randomized, double-blind, clinical trial study, 31 patients with vitiligo vulgaris and focal vitiligo involving the eyelids were evaluated. Patients were randomly divided into two groups. First group received topical latanoprost gel twice daily for 12 weeks, whereas the second group received placebo with the same protocol. To evaluate severity of the disease the VIDA rating system was used. Serial photos of the patches were taken to compare and evaluate the repigmentation percentage of the patches. The patients in both groups had almost similar VIDA score (p > .05). First group showed improved pigmentation, whereas participants in the second group did not show any improvement in the pigmentation. The group treated with latanoprost showed significant reduction in the symptoms of the disease, whereas those treated with placebo did not show any alteration (p > .05). No significant complications were observed in either groups. Latanoprost proved effective in treating vitiligo disease involving eyelids.


Assuntos
Pálpebras , Latanoprosta/administração & dosagem , Vitiligo/tratamento farmacológico , Administração Tópica , Adolescente , Criança , Método Duplo-Cego , Feminino , Géis , Humanos , Masculino , Índice de Gravidade de Doença , Pigmentação da Pele/efeitos dos fármacos , Resultado do Tratamento , Vitiligo/patologia , Adulto Jovem
7.
Dermatol Ther ; 33(1): e13194, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31846144

RESUMO

In this study, we report our multicentric experience of synthetic medical certified polyamide hair implants in male androgenetic, female menopausal, and chronic alopecia. Biofibre hair implantation was performed by means of a standardized, mini-invasive technique followed by regular postoperative care along 3 years. From May 2015, 278 patients were enrolled and 253 completed the trial; 202 men (79.9%) versus 51 women (20,1%). The average age was 43(± 4.29); 179 patients (70.1%) had taken previous treatments for alopecia. We evaluated efficacy (as judged by Hamilton scale grading, covered area percent, surgeon, and patient's subjective evaluation) and safety (as judged by adverse events). The overall scalp surface restored with artificial hair (mm2 spaced) and pre-postoperative general customers' satisfaction (by Hamilton scale grading) are reported, showing a significant (98,14%) subjective and objective improvement of the self-image. Twenty-two cases (8.75%) declared minor side effects generally counteracted by topical or short course systemic antibiotic and anti-inflammatory treatment. The average number of implanted fibers was 2,295 (SD 2.805; SE 200.9) ranging from 300 to 16,000. The average duration of pain and tenderness at the implant area was 2.2 days (SD 4.096; SE 0.2933) ranging from 1 to 20 days. A diagrammatic comparison of the Hamilton scale grading before and after the trial showed a dramatic improvement with the majority of the patients being in Hamilton grade II after implantation.


Assuntos
Alopecia/cirurgia , Próteses e Implantes , Implantação de Prótese/métodos , Adulto , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Nylons/química , Dor/epidemiologia , Dor/etiologia , Satisfação do Paciente , Resultado do Tratamento
8.
Dermatol Ther ; 32(6): e13119, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31606942

RESUMO

The eyes are an important component of facial aesthetics. They are in the center of an anatomical area of the face very important for rejuvenation procedures, the so-called "periorbital region." The appearance of the eyes therefore decisively influences the perception of the aesthetics and aging of the entire face. In juvenile age, the skin of the periocular area is elastic and tonic, without sun damage; the eyebrow is full, well defined, and not descending; there is a clear and visible fold of the upper eyelid, with minimal dermatochalasis; the lower eyelid is tense and well positioned. The aim of this preliminary study is to define a protocol for the use of plasma technology in the treatment of aging signs of the periorbital region. The protocol is aimed to provide predictable, constant, and safe results.


Assuntos
Blefaroplastia/métodos , Técnicas Cosméticas , Pálpebras , Rejuvenescimento , Adulto , Idoso , Feminino , Humanos , Pessoa de Meia-Idade , Envelhecimento da Pele
9.
Dermatol Ther ; 32(6): e13104, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31587447

RESUMO

Isotretinoin (ISO) is a first-generation retinoid discovered in 1952 and approved by the FDA for the treatment of nodulocystic acne in 1982. The anti-inflammatory properties of ISO have found its use in disorders other than acne. ISO can create psychiatric problems, including depression and suicidal ideation. These neuropsychiatric problems are very similar to disorders secondary to hyperhomocysteinemia (HHcy), vitamin B12, and folic acid (vitamin B9) deficiencies. Given that previous literature suggested folate supplementation improved the efficacy of traditional antidepressant medications, clinicians may wish to consider folate supplementation for patients with depression or possible depressive symptoms, such as acne patients with genetic susceptibility. Brain-derived neurotrophic factor may be a cytokine-specific screening biomarker in immune-based antidepressive therapy.


Assuntos
Depressão/tratamento farmacológico , Ácido Fólico/administração & dosagem , Isotretinoína/efeitos adversos , Acne Vulgar/complicações , Acne Vulgar/tratamento farmacológico , Fator Neurotrófico Derivado do Encéfalo/sangue , Fator Neurotrófico Derivado do Encéfalo/fisiologia , Depressão/etiologia , Ácidos Graxos/administração & dosagem , Ácidos Graxos/fisiologia , Humanos , Hiper-Homocisteinemia/classificação
10.
Dermatol Ther ; 32(6): e13099, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31579989

RESUMO

Treatment of wounds, especially in patients with systemic diseases, is very difficult and time consuming, and it represents great challenge. Complications like infections and impaired healing are regularly seen in these patients, sometimes leaving almost no other treating option, but amputation surgery. In wound healing process, platelets play one of key roles, both in hemostasis, and, by releasing many growth factors, in reepithelization and tissue remodeling. Platelet concentrates are defined as autologous or homologous platelet derivatives with a platelet concentration higher than it is usually in human blood. Concentration of platelets needed to affect wound healing should be 1,000,000/µl. This is a report about patient with pemphigus vulgaris and Type 2 diabetes mellitus, who got injury of the left lower leg. Traditional surgical methods of wound closure and vacuum-assisted closure therapy were ineffective. Homologous platelet gel was used topically, resulting in wound closure, without any adverse effects.


Assuntos
Plaquetas , Diabetes Mellitus Tipo 2/complicações , Pênfigo/complicações , Ferimentos e Lesões/terapia , Idoso , Feminino , Géis , Humanos , Plasma Rico em Plaquetas , Cicatrização/fisiologia
11.
J Chem Phys ; 150(4): 041731, 2019 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-30709272

RESUMO

Mixed metal oxides of earth-abundant 3d transition metals are an interesting class of materials that show interesting magnetic properties and a significant synergistic effect as catalysts for electrochemical oxygen evolution compared to simple unary oxides. However, the exact atomic-scale nature of such mixed oxide phases and the link to their interesting physico-chemical properties are poorly understood. Here, a combination of scanning tunneling microscopy and x-ray photoemission spectroscopy reveals that Fe species embed in a facile way into CoO bilayers on Au(111) resulting in an Fe doped oxide. Density functional theory and the spectroscopic fingerprint from x-ray photoemission spectroscopy reveal that the Fe dopants in the cobalt oxide matrix assume a higher oxidation state than in the structurally corresponding unary bilayer oxide. Furthermore, the substituted Fe is structurally displaced further away from the Au than the metal in either of the corresponding pure unary oxides. Both O and to a smaller extent Co in the nearest coordination shell are also structurally and electronically perturbed. The interesting effects observed in the bilayer binary oxides may enable a better fundamental understanding of the nature of doping of metal oxides, in general, and promotion effects in catalytic applications.

12.
Phys Chem Chem Phys ; 20(5): 3813-3818, 2018 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-29349458

RESUMO

The reactivity of solid oxide surfaces towards adsorption of oxygen and hydrogen is a key metric for the design of new catalysts for electrochemical water splitting. In this paper, we report on trends in the adsorption energy of different adsorbed intermediates derived from the oxidation and reduction of water for ternary ABO3 oxides in the cubic perovskite structure. Our findings support a previously reported trend that rationalizes the observed lower bound in oxygen evolution (OER) overpotentials from correlations in OH* and OOH* adsorption energies. In addition, we report hydrogen adsorption energies that may be used to estimate hydrogen evolution (HER) overpotentials along with potential metrics for electrochemical metastability in reducing environments. We also report and discuss trends between atom-projected density of states and adsorption energies, which may enable a design criteria from the local electronic structure of the active site.

13.
Nat Mater ; 16(1): 70-81, 2016 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-27994241

RESUMO

The conversion of sunlight into fuels and chemicals is an attractive prospect for the storage of renewable energy, and photoelectrocatalytic technologies represent a pathway by which solar fuels might be realized. However, there are numerous scientific challenges in developing these technologies. These include finding suitable materials for the absorption of incident photons, developing more efficient catalysts for both water splitting and the production of fuels, and understanding how interfaces between catalysts, photoabsorbers and electrolytes can be designed to minimize losses and resist degradation. In this Review, we highlight recent milestones in these areas and some key scientific challenges remaining between the current state of the art and a technology that can effectively convert sunlight into fuels and chemicals.

14.
Food Technol Biotechnol ; 55(4): 484-495, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29540983

RESUMO

Regardless of its highly valuable nutritive composition, goat's milk is less preferred by consumers due to its specific sensory characteristics that are very often regarded as undesirable. On the other hand, traditional medicinal plants from Lamiaceae family, due to their rich bioactive composition, especially polyphenols, and desirable aroma profile, can be used to enhance and improve bioactive and sensory properties of food. In the present study nutritively valuable beverages were produced by enrichment of goat's milk with medicinal plant extracts derived from the Lamiaceae family and stabilized by homogenization with high intensity ultrasound treatment. The impact of plant species (lemon balm, mint, lavender, rosemary and sage) and ultrasound treatment duration (5 or 10 min) on the physicochemical, bioactive and sensory characteristics of enriched beverages was evaluated. The addition of plant extracts to goat's milk significantly increased the concentration of bioactive components (rosmarinic acid, hydroxycinnamic acid derivatives and luteolin derivatives), in dependence of the added plant extract. The prolongation of the ultrasound homogenization markedly decreased the fat globule size and thus beneficially affected the product stability. Apart from the achieved bioactive enrichment and stability, the developed beverages exhibited significantly improved sensory properties in comparison to plain goat's milk, with the highest overall acceptability determined for samples enriched with mint and rosemary.

16.
Int J Food Sci Nutr ; 67(1): 53-66, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26707111

RESUMO

Consumer acceptability and sensory properties of liquorice root (Glycyrrhiza glabra L.) were evaluated. Quantitation of total polyphenolics and glycyrrhizic acid (GA), as well as the antioxidant capacity of liquorice extracts, was conducted and their biological effects (cytotoxic, antioxidative/pro-oxidative activity, lipid peroxidation on human laryngeal carcinoma cell line) compared to the ones of their predominant bioactive compound - GA. Conducted consumer survey revealed poor familiarity with liquorice (12.37% of correspondents), but willingness towards its use as an alternative sweetener (77.32% of consumers). Polyphenolic content of evaluated extracts ranged from 1018.18 to 1277.27 mg gallic acid equivalents (GAE)/l while GA content varied between 2179.53 and 2944.13 mg/l. The most pronounced cytotoxic effect (60%) and lipid peroxidation were exerted by treatment with the highest applied extract concentrations (10 mg/ml). Pure GA exhibited cytotoxic and pro-oxidative effects at concentrations of 0.12-0.6 mg/ml. Due to high GA content, coupled with its pronounced cytotoxic activity, the intake of liquorice root should be limited.


Assuntos
Antioxidantes/farmacologia , Comportamento do Consumidor , Citotoxinas/farmacologia , Glycyrrhiza/química , Ácido Glicirrízico/farmacologia , Polifenóis/farmacologia , Edulcorantes/farmacologia , Adolescente , Adulto , Antineoplásicos Fitogênicos/análise , Antineoplásicos Fitogênicos/farmacologia , Antioxidantes/análise , Citotoxinas/análise , Feminino , Ácido Glicirrízico/análise , Humanos , Neoplasias Laríngeas/tratamento farmacológico , Peroxidação de Lipídeos , Masculino , Pessoa de Meia-Idade , Fitoterapia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Raízes de Plantas/química , Polifenóis/análise , Espécies Reativas de Oxigênio/análise , Espécies Reativas de Oxigênio/farmacologia , Edulcorantes/análise , Paladar , Adulto Jovem
17.
Phys Chem Chem Phys ; 17(4): 2634-40, 2015 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-25502921

RESUMO

In this work, we present first-principles calculations describing the catalytic activity for of a set of photoelectrocatalysts identified as candidates for total water splitting in a previous screening study for bulk stability and bandgap. Our Density Functional Theory (DFT) calculations of the intermediate energetics for hydrogen evolution and oxygen evolution suggest that none of the proposed materials has the ideal combination of bandgap and surface chemical properties that should allow for total water splitting in a single material. This result suggests that co-catalysts are necessary to overcome the kinetic limitations of the both reactions, although some materials may catalyze one half-reaction, as has been observed in experiment.

19.
J Food Sci Technol ; 52(12): 7723-34, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26604346

RESUMO

Pursuant to the tendencies of producing functional foods, attractive to a wide range of consumers, in this study chocolates enriched with freeze dried (FD) and concentrated (CE) nettle extracts were formulated, and their polyphenolic and antioxidant capacity stability evaluated during 12 months of storage. A simple aqueous extraction procedure of nettle was developed, and the defined extract evaluated for its cytotoxic and antioxidant/prooxidant activity on human colon cancer cell line (SW 480). An increase in total polyphenolic content, chlorogenic acid and flavonoid derivatives (originating from nettle extract) contents was achieved in enriched chocolates. Implementation of FD extract enabled higher increase of polyphenolic content in comparison to CE extract. During storage, fluctuations of polyphenolic content were observed, but the final bioactive parameters did not differ (or increased) from the initial ones. Nettle enriched chocolates exhibited more intense bitterness and astringency, while dark chocolates were preferred over milk and semisweet ones.

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