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1.
Front Biosci (Landmark Ed) ; 29(1): 31, 2024 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-38287810

RESUMO

BACKGROUND: Next-generation 5G communication technology involves increasing use of 3-100 GHz wireless bands in population centers. Though still non-ionizing, this implies higher radiation energy vs. existing bands. The range is also shorter, needing more numerous emitters, closer to the user-resulting in higher electromagnetic energy exposure. With no universal consensus regarding exposure risks, there is some concern among the public and the scientific community, following indications that 5G radiation can impact immune function, trigger inflammatory responses, and influence expression of genes affecting protein folding, oxidative stress, tissue/extracellular matrix (ECM) matrix turnover, and more. This work aims at identifying botanical extracts for protection of human skin from these impacts, based on a preliminary cell culture-based model. METHODS: We irradiated human epidermal keratinocytes at 6 GHz, evaluating effects on Interleukin1-α (IL1-α), a key inflammatory cytokine; TIMP metallopeptidase inhibitor 1 (TIMP1), shown to inhibit collagenase; Angiopoietin-like protein 4 (ANGPLT4), which plays a role in wound healing and epidermal differentiation; and S100 calcium-binding protein A9 (S100A9), involved in immune recruitment during injury, by enzyme-linked immunosorbent assay (ELISA) and immunostaining. We next used this model to identify substances able to mitigate the effects of 5G irradiation, through the evaluation of the influence of treatment by one of several botanical extracts on the observed effects of 5G irradiation. RESULTS: After a remarkably short 1-h exposure, clear effects on keratinocyte function were observed: increased inflammatory cytokine IL1-α; reduced collagenase inhibitor TIMP1; increased wound healing/differentiation facilitator ANGPLT4; and increased SA100A9, involved in immune recruitment during injury. On this basis, we then showed the protective effects of selected botanical extracts, capable of reducing the increase in IL1-α induced by 5G exposure, possibly in part due to anti-inflammatory and anti-oxidant properties of compounds present in these extracts. CONCLUSIONS: Our results show a clear influence of 5G irradiation on the keratinocytes, possibly indicating injury and damage responses. What's more, we showed how these preliminary data can be used to identify botanical extracts capable of offering some protection against these effects for users of 5G technology, e.g., when employed as active ingredients in protective cosmetic applications.


Assuntos
Queratinócitos , Pele , Humanos , Dados Preliminares , Queratinócitos/metabolismo , Citocinas/metabolismo , Técnicas de Cultura de Células
2.
Phys Rev Lett ; 130(23): 233801, 2023 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-37354410

RESUMO

We propose superluminal solitons residing in the momentum gap (k gap) of nonlinear photonic time crystals. These gap solitons are structured as plane waves in space while being periodically self-reconstructing wave packets in time. The solitons emerge from modes with infinite group velocity causing superluminal evolution, which is the opposite of the stationary nature of the analogous Bragg gap soliton residing at the edge of an energy gap (or a spatial gap) with zero group velocity. We explore the faster-than-light pulsed propagation of these k-gap solitons in view of Einstein's causality by introducing a truncated input seed as a precursor of a signal velocity forerunner, and find that the superluminal propagation of k-gap solitons does not break causality.


Assuntos
Fótons , Reprodução , Movimento (Física)
3.
Mar Drugs ; 20(2)2022 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-35200634

RESUMO

Glycation, and the resulting buildup of advanced glycation end products (AGEs), is recognized as a key driver of cumulative skin damage and skin aging. Dunaliella salina is a halophile microalga adapted to intense solar radiation through the production of carotenoids. We present a natural supercritical CO2 extract of Dunaliella salina rich in the colorless carotenoids phytoene and phytofluene. The extract exhibited antiglycation and anti-inflammatory activities in ex vivo testing, showing strongly reduced formation of N-ε-carboxy-methyl-lysine with exposure to methylglyoxal, reduced AGE receptor levels, and significantly reduced interleukins 6 and 8. In a placebo-controlled clinical study under intense solar exposure, the extract significantly reduced the skin's glycation scores and its sensitivity to histamine; key skin aging parameters were also significantly improved vs. placebo, including wrinkle counts and spots. These results demonstrate the value of this Dunaliella salina extract, rich in colorless carotenoids, as an antiglycative, anti-inflammatory, and antiaging active ingredient, including in high-irradiation contexts.


Assuntos
Anti-Inflamatórios/farmacologia , Produtos Biológicos/farmacologia , Microalgas/química , Envelhecimento da Pele/efeitos dos fármacos , Adulto , Método Duplo-Cego , Feminino , Produtos Finais de Glicação Avançada/efeitos dos fármacos , Histamina/metabolismo , Humanos , Pessoa de Meia-Idade
4.
Phys Rev Lett ; 127(9): 093901, 2021 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-34506166

RESUMO

Synthetic-space topological insulators are topological systems with at least one spatial dimension replaced by a periodic arrangement of modes, in the form of a ladder of energy levels, cavity modes, or some other sequence of modes. Such systems can significantly enrich the physics of topological insulators, in facilitating higher dimensions, nonlocal coupling, and more. Thus far, all synthetic-space topological insulators relied on active modulation to facilitate transport in the synthetic dimensions. Here, we propose dynamically invariant synthetic-space photonic topological insulators: a two-dimensional evolution-invariant photonic structure exhibiting topological properties in synthetic dimensions. This nonmagnetic structure is static, lacking any kind of modulation in the evolution coordinate, yet it displays an effective magnetic field in synthetic space, characterized by a Chern number of one. We study the evolution of topological states along the edge, and on the interface between two such structures with opposite synthetic-space chirality, and demonstrate their robust unidirectional propagation in the presence of defects and disorder. Such topological structures can be realized in photonics and cold atoms and provide a fundamentally new mechanism for topological insulators.

5.
Light Sci Appl ; 9(1): 200, 2020 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-33353936

RESUMO

Artificial gauge fields the control over the dynamics of uncharged particles by engineering the potential landscape such that the particles behave as if effective external fields are acting on them. Recent years have witnessed a growing interest in artificial gauge fields generated either by the geometry or by time-dependent modulation, as they have been enablers of topological phenomena and synthetic dimensions in many physical settings, e.g., photonics, cold atoms, and acoustic waves. Here, we formulate and experimentally demonstrate the generalized laws of refraction and reflection at an interface between two regions with different artificial gauge fields. We use the symmetries in the system to obtain the generalized Snell law for such a gauge interface and solve for reflection and transmission. We identify total internal reflection (TIR) and complete transmission and demonstrate the concept in experiments. In addition, we calculate the artificial magnetic flux at the interface of two regions with different artificial gauge fields and present a method to concatenate several gauge interfaces. As an example, we propose a scheme to make a gauge imaging system-a device that can reconstruct (image) the shape of an arbitrary wavepacket launched from a certain position to a predesigned location.

6.
Nat Commun ; 8(1): 940, 2017 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-29038547

RESUMO

Disruption of the reprogrammed energy management system of malignant cells is a prioritized goal of targeted cancer therapy. Two regulators of this system are the Fer kinase, and its cancer cell specific variant, FerT, both residing in subcellular compartments including the mitochondrial electron transport chain. Here, we show that a newly developed inhibitor of Fer and FerT, E260, selectively evokes metabolic stress in cancer cells by imposing mitochondrial dysfunction and deformation, and onset of energy-consuming autophagy which decreases the cellular ATP level. Notably, Fer was also found to associate with PARP-1 and E260 disrupted this association thereby leading to PARP-1 activation. The cooperative intervention with these metabolic pathways leads to energy crisis and necrotic death in malignant, but not in normal human cells, and to the suppression of tumors growth in vivo. Thus, E260 is a new anti-cancer agent which imposes metabolic stress and cellular death in cancer cells.The tyrosine-kinases Fer/FerT associate with the mitochondrial electron transport chain in cancer cells supporting their metabolic reprogramming. Here the authors discover a compound that disrupts Fer /FerT activity and selectively induces cell death of cancer cell lines displaying anti-tumor activity in vivo.


Assuntos
Neoplasias do Colo/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologia , Proteínas Tirosina Quinases/antagonistas & inibidores , Estresse Fisiológico/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto , Animais , Antineoplásicos/síntese química , Antineoplásicos/farmacocinética , Antineoplásicos/farmacologia , Linhagem Celular , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Neoplasias do Colo/genética , Neoplasias do Colo/metabolismo , Células HCT116 , Células HT29 , Humanos , Camundongos Endogâmicos ICR , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Necrose , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/farmacocinética , Proteínas Tirosina Quinases/metabolismo , Carga Tumoral/efeitos dos fármacos
7.
Bioresour Technol ; 102(5): 4265-9, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21208797

RESUMO

This work offers an optimized method for the direct conversion of harvested Nannochloropsis algae into bio-diesel using two novel techniques. The first is a unique bio-technology-based environmental system utilizing flue gas from coal burning power stations for microalgae cultivation. This method reduces considerably the cost of algae production. The second technique is the direct transesterification (a one-stage method) of the Nannochloropsis biomass to bio-diesel production using microwave and ultrasound radiation with the aid of a SrO catalyst. These two techniques were tested and compared to identify the most effective bio-diesel production method. Based on our results, it is concluded that the microwave oven method appears to be the most simple and efficient method for the one-stage direct transesterification of the as-harvested Nannochloropsis algae.


Assuntos
Biocombustíveis/microbiologia , Reatores Biológicos/microbiologia , Biotecnologia/métodos , Micro-Ondas , Estramenópilas/metabolismo , Ultrassom , Esterificação , Ácidos Graxos/análise , Estramenópilas/química , Estrôncio
8.
Mycorrhiza ; 11(3): 129-136, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24595432

RESUMO

Linear variable differential transformer (LVDT) sensors were used to detect continuous diameter growth responses of Pinus pinea (stone pine) seedlings inoculated with the ectomycorrhizal fungus Rhizopogon roseolus. Colonised and non-colonised seedlings provided with sensors were submitted to different water regimes in two consecutive experiments established in a controlled-temperature greenhouse module (cycle 1), and in an adjacent module without temperature control (cycle 2). Under regular irrigation, colonised seedlings showed significantly higher growth than non-colonised seedlings. Water-stressed seedlings showed no benefit from inoculation in terms of growth. Also, seedlings with a high colonisation level recovered more slowly from water stress than control seedlings. A significant positive relationship between maximum daily shrinkage (amplitude of the daily stem contraction) and global radiation was observed only in the first water-stress period in cycle 1 and in regularly irrigated seedlings in both cycles. However, no differential responses due to inoculation were observed. The mycorrhizal colonisation of the seedlings at the end of the experiment was related with the initial colonisation level. Mycorrhizal colonisation by R. roseolus in old roots was maintained at significantly higher levels in seedlings which had an initial colonisation level >50% than in seedlings with <50% initial colonisation. Also, more newly formed roots became colonised in seedlings which had an initial colonisation level >50% than in seedlings with an initial colonisation <50%, which had almost no new root colonisation. From the results obtained, it can be concluded that LVDT sensors can be used to detect a differential response of plants according to water supply, mycorrhizal status and, in some cases, to their colonisation level. The results are discussed in relation to the predictive possibilities of the method for the selection of efficient mycorrhizal fungi for the promotion of plant growth.

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