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1.
Sci Rep ; 11(1): 13804, 2021 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-34226623

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been a pandemic threat worldwide and causes severe health and economic burdens. Contaminated environments, such as personal items and room surfaces, are considered to have virus transmission potential. Ultraviolet C (UVC) light has demonstrated germicidal ability and removes environmental contamination. UVC has inactivated SARS-CoV-2; however, the underlying mechanisms are not clear. It was confirmed here that UVC 253.7 nm, with a dose of 500 µW/cm2, completely inactivated SARS-CoV-2 in a time-dependent manner and reduced virus infectivity by 10-4.9-fold within 30 s. Immunoblotting analysis for viral spike and nucleocapsid proteins showed that UVC treatment did not damage viral proteins. The viral particle morphology remained intact even when the virus completely lost infectivity after UVC irradiation, as observed by transmission electronic microscopy. In contrast, UVC irradiation-induced genome damage was identified using the newly developed long reverse-transcription quantitative-polymerase chain reaction (RT-qPCR) assay, but not conventional RT-qPCR. The six developed long RT-PCR assays that covered the full-length viral genome clearly indicated a negative correlation between virus infectivity and UVC irradiation-induced genome damage (R2 ranging from 0.75 to 0.96). Altogether, these results provide evidence that UVC inactivates SARS-CoV-2 through the induction of viral genome damage.


Assuntos
Desinfecção , RNA Viral/efeitos da radiação , SARS-CoV-2 , Raios Ultravioleta , Inativação de Vírus/efeitos da radiação , Animais , COVID-19/prevenção & controle , Chlorocebus aethiops , Desinfecção/métodos , Genoma Viral/genética , Proteínas do Nucleocapsídeo/genética , RNA Viral/análise , SARS-CoV-2/patogenicidade , SARS-CoV-2/efeitos da radiação , Células Vero
2.
Se Pu ; 39(2): 105-111, 2021 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-34227341

RESUMO

Ribonucleic acid (RNA) rarely exists alone in the cell. RNAs interact with a variety of proteins and form RNA-protein complexes (RP-complexes) in every step of their life cycle, from transcription to degradation. These RP-complexes play key roles in regulating a variety of physiological processes. Defects in the composition and function of RP-complexes have been associated with many diseases, including metabolic disorders, muscular atrophy, autoimmune diseases, and cancer. It is hence evident that deciphering the highly complex interaction network of RNA-binding proteins (RBPs) and their RNA targets will provide a better understanding of disease development and lead to the discovery of new targets for cancer therapy. Large-scale identification of RP-complexes at the omics level is a prerequisite for obtaining insights into the complex RNA-protein interaction network. As the first step in omics-wide decoding of RP-complexes, enrichment and purification of RP-complexes is a highly challenging task. Recently, intensive efforts have been undertaken to better enrich and identify RP-complexes. Generally, the enrichment strategies can be classified into two major categories: in vitro and in vivo. Although it has been successfully applied in many studies, the in vitro transcribed bait RNA lacks modifications or structural similarity compared with its natural counterpart. Further, since the proteins relocate and remodel after cell lysis, the use of cell lysates as a protein source may result in capturing false interacting proteins that bind non-physiologically with the bait RNA. Finally, weak interactions between the non-covalently bound proteins and RNA require mild washing to remove non-specific binding, which needs careful optimization. However, substantial sample loss is inevitable. To overcome the disadvantages of in vitro approaches, in vivo cross-linking strategies that "freeze" natural RNA-protein complexes in intact cells via covalent cross-linking have become increasingly popular. The in vivo methods allow RNA to interact with proteins in the intracellular environment. Therefore, the RP-complexes formed under physiological conditions are more biologically relevant than those obtained by in vitro methods. We herein summarize recent in vivo methodological advances in the large-scale enrichment and identification of RP-complexes, including cross-linking and immunoprecipitation (CLIP) and related methods, click chemistry-assisted methods, and organic phase separations. CLIP involves irradiating living cells with 254-nm ultraviolet (UV) light to establish covalent bonds between RNA and proteins. This enables CLIP to purify RNAs bound to a specific RBP under conditions that are stringent enough to prevent co-purification of nonspecifically bound proteins or free RNAs. Since the original study, multiple variant protocols have been derived to increase both efficiency and convenience. Photoactivatable ribonucleoside-enhanced-CLIP (PAR-CLIP) introduces a variation in the crosslinking strategy. Cells were preincubated with photoactivatable ribonucleosides 4-thiouridine (4SU) or 6-thioguanosine (6SG), which enables protein-RNA crosslinking with 365-nm UV-A irradiation. It increases the efficiency of cross-linking between RNA and RBPs and is particularly valuable for studying the interactions between RBPs and nascent RNA. Using a click chemistry-assisted strategy, an alkyne modified uridine analog, 5-ethynyluridine (EU), was incorporated into nascent RNAs via metabolic incorporation in living cells. Combined with UV irradiation-based cross-linking, the alkyne-functionalized RNA and the bound proteins were purified in a poly A-independent fashion by the highly selective bioorthogonal copper (I)-catalyzed azide-alkyne cycloaddition using azide-modified beads. Thus, full lists of both coding and non-coding RNAs with their interacting proteins can be purified, which is a major methodological advance. Organic phase separation methods exploiting the physicochemical difference between cross-linked RP-complexes and free RNA and proteins do not require metabolic-based alkyne labeling or polyA-based RNA capture. Each method has unique strengths and drawbacks, which makes it important to select optimal approaches for the biological question being addressed. We hope that this review points out the current limitations and provides future directions to facilitate further development of methods for large-scale investigation of RP-complexes.


Assuntos
Proteínas de Ligação a RNA , RNA , Sítios de Ligação , Química Click , Imunoprecipitação , RNA/análise , Proteínas de Ligação a RNA/análise , Raios Ultravioleta
3.
Photobiomodul Photomed Laser Surg ; 39(7): 437-438, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34264764

RESUMO

The numerous dermatology clinics have decreased or stopped phototherapy sessions due to the increased risk of getting COVID-19 during the current pandemic. In this context, poorly ventilated phototherapy units (PUs) should be redesigned in order to continue UV-based therapies and to protect our patients from getting COVID-19. Recently, it has been reported that ultraviolet C (UVC)-related dose and virus concentration may play a decisive role in the virucidal activity. Considering air changes per hour and viral inactivation time, 30 min of 30-W UVC radiation is able to inactivate poorly ventilated PUs of 3-4 m length, 5.5-7 m width, and 2.7-3 m height. Upper-air UVC radiation for 30 min between sessions would allow us to have more treatment options for numerous dermatological diseases in novel PUs during the COVID-19 pandemic and possible future pandemics.


Assuntos
COVID-19/prevenção & controle , Controle de Infecções/métodos , Fototerapia/instrumentação , SARS-CoV-2/efeitos da radiação , Inativação de Vírus/efeitos da radiação , Desenho de Equipamento , Humanos , Pandemias , Raios Ultravioleta , Ventilação
4.
Int J Mol Sci ; 22(11)2021 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-34200222

RESUMO

Collagen hydrolysates have been suggested as a favorable antiaging modality in skin photoaged by persistent exposure to ultraviolet radiation (UV). The current study evaluated the beneficial effect of collagen hydrolysates (fsCH) extracted from Pangasius hypophthalmus fish skin on wrinkle formation and moisture preservation in dorsal skin of hairless mice challenged with UV-B. Inter-comparative experiments were conducted for anti-photoaging among fsCH, retinoic acid (RA), N-acetyl-D-glucosamine (NAG), and glycine-proline-hydroxyproline (GPH). Treating human HaCaT keratinocytes with 100-200 µg/mL fsCH reciprocally ameliorated the expression of aquaporin 3 (AQP3) and CD44 deranged by UV-B. The UV-B-induced deep furrows and skin thickening were improved in parched dorsal skin of mice supplemented with 206-412 mg/kg fsCH as well as RA and GPH. The UV-B irradiation enhanced collagen fiber loss in the dorsal dermis, which was attenuated by fsCH through enhancing procollagen conversion to collagen. The matrix metalloproteinase expression by UV-B in dorsal skin was diminished by fsCH, similar to RA and GPH, via blockade of collagen degradation. Supplementing fsCH to UV-B-irradiated mice decreased transepidermal water loss in dorsal skin with reduced AQP3 level and restored keratinocyte expression of filaggrin. The expression of hyaluronic acid synthase 2 and hyaluronidase 1 by UV-B was remarkably ameliorated with increased production of hyaluronic acid by treating fsCH to photoaged mice. Taken together, fsCH attenuated photoaging typical of deep wrinkles, epidermal thickening, and skin water loss, like NAG, RA, or GPH, through inhibiting collagen destruction and epidermal barrier impairment.


Assuntos
Colágeno/farmacologia , Proteínas na Dieta/farmacologia , Envelhecimento da Pele/efeitos dos fármacos , Dermatopatias/tratamento farmacológico , Pele/efeitos dos fármacos , Raios Ultravioleta/efeitos adversos , Animais , Masculino , Camundongos , Camundongos Pelados , Pele/patologia , Pele/efeitos da radiação , Envelhecimento da Pele/patologia , Envelhecimento da Pele/efeitos da radiação , Dermatopatias/etiologia , Dermatopatias/patologia
5.
Int J Mol Sci ; 22(13)2021 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-34206765

RESUMO

A [H2DPEphos][MnX4] [X = Br, Cl] tetrahalomanganates(II) with P,P'-diprotonated bis[2-(diphenylphosphino)phenyl]ether cation has been designed and investigated in photophysics and EPR terms. The complexes exhibit a green luminescence resulted from the Mn(II) d-d transitions (4T1→6A1) with the wavelength-excitation dependence of the quantum yield. The solid [H2DPEphos][MnBr4] complex exhibits a bright green phosphorescence (λmax = 515 nm) with the high luminescence quantum yield depending on the excitation energy whereas the solid [H2DPEphos][MnCl4] complex exhibits a very weak phosphorescence (λmax = 523 nm). The unexpected shorter luminescence lifetime for the [H2DPEphos][MnCl4] than for the [H2DPEphos][MnBr4] at 300 K can be a result of the higher non-radiative relaxation contribution. On the one hand, the non-covalent PH…X(Mn) interactions quench the manganese(II) luminescence. On the other hand, the PH…X(Mn) interactions are a pathway of the excitation transfer from [H2DPEphos]2+ to [MnX4]2-.


Assuntos
Substâncias Luminescentes/química , Compostos de Manganês/química , Marcadores de Spin , Absorção de Radiação , Espectroscopia de Ressonância de Spin Eletrônica/métodos , Prótons , Raios Ultravioleta
6.
Molecules ; 26(12)2021 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-34204433

RESUMO

Catechins are a part of the chemical family of flavonoids, a naturally occurring antioxidant, and a secondary metabolite in certain plants. Green tea catechins are well recognized for their essential anti-inflammatory, photo-protective, antioxidant, and chemo-preventive functions. Ultraviolet radiation is a principal cause of damage to the skin. Studies observed that regular intake of green tea catechins increased the minimal dose of radiation required to induce erythema. The objectives of this systematic review and meta-analysis are to determine the effectiveness of green tea catechins in cutaneous erythema and elucidate whether green tea catechin consumption protects against erythema (sunburn) inflammation. A comprehensive literature search was conducted to identify the relevant studies. Two researchers carried out independent screening, data extraction, and quality assessment according to the guidelines of Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA). The pooled effect of green tea catechins on protection against erythema was assessed using approaches fixed-effects or random-effects model to quantify the effectiveness of green tea catechins in the erythema dose-response. Studies not be included in meta-analyses were summarized narratively. Six randomized controlled studies of enrolled studies regularly administrated green tea catechins orally for 6 to 12 weeks involving healthy volunteers comprising a total of 100 participants were included in the analysis. The results revealed green tea catechins have favorable protection against erythema inflammation even at increased minimal erythema dose (MED) of ultraviolet radiation. Meta-analysis results confirm oral supplementation of green tea catechins is highly effective at low-intensity ultraviolet radiation-induced erythema response (MED range; 1.25-1.30) compared to placebo, showing a significant pooling difference (p = 0.002) in erythema index (SMD: -0.35; 95% CI, -0.57 to -0.13; I2 = 4%, p = 0.40) in the random-effects model. The pro-inflammatory signaling pathways through oral supplementation with green tea catechins are an attractive strategy for photo-protection in healthy human subjects and could represent a complementary approach to topical sunscreens. Therefore, studies that involved green tea catechin in topical applications to human subjects were also evaluated separately, and their meta-analysis is presented as a reference. The evidence indicates that regular green tea catechin supplementation is associated with protection against UV-induced damage due to erythema inflammation.


Assuntos
Catequina/farmacologia , Eritema/tratamento farmacológico , Chá/química , Animais , Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Catequina/química , Eritema/metabolismo , Eritema/prevenção & controle , Flavonoides/metabolismo , Flavonoides/farmacologia , Humanos , Inflamação/tratamento farmacológico , Pele/metabolismo , Protetores Solares/farmacologia , Chá/metabolismo , Raios Ultravioleta/efeitos adversos
7.
Georgian Med News ; (314): 162-166, 2021 May.
Artigo em Russo | MEDLINE | ID: mdl-34248048

RESUMO

It seems that safety of the impact of the UVA on the skin is associated with insidious identifying of early manifestation of damage and distant consequences of impact on the skin and the whole organism. The imagination of safety of UVA exposure has led to wide spread of radiator of UV rays of range A. This scientific research was devoted to identifying of positive and negative impact of UVA on the skin. The aim of the study was to investigate the morphological and functional state of the guinea pigs' skin under the influence of local fractional UVA radiation. Materials and methods. Studies were conducted on albino guinea pigs that weight 300-350 g. The local fractional regime of exposure was obtained by UV radiator OUFK-03, which generates mainly UVA radiation with the aim of creating the model of exposure in the most similar to real conditions. The shaved area (2x2 cm) of animals' skin (n=6) was exposed for 30 minutes for 5 days. Guinea pigs were located in a distance of 10 centimeters from the source of exposure. Experiments with animals were finished on the 6-th day after exposure. All animals were deduced from the experiment with the help of general anesthesia keeping the principles of bioethics with the aim of investigation of peculiarities of morphological changes of skin. Visible changes in the morphological and functional state of the skin were detected on the 6-th day after irradiation: signs of acute inflammation and a tendency to chronicity of the process, multiple, compared with normal, thickening of the epidermis, degenerative changes in epidermocytes, hyper- and parakeratosis, focal destructive changes in connective tissue fibers in the dermis, which are accompanied by reactive inflammatory processes. Signs of starting reparative processes in proliferative form of functional active fibroblasts and increasing of collagenogenesis at sites of damage of collagen and elastin fibers are market simultaneously. It is considered that the negative effects of UVA in studied regime on the skin, the task of developing of depending actions is to reduce negative UVA impact which will be the aim of our next researches.


Assuntos
Envelhecimento da Pele , Pele , Animais , Colágeno , Epiderme , Cobaias , Raios Ultravioleta/efeitos adversos
8.
Nat Commun ; 12(1): 4171, 2021 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-34234116

RESUMO

Here we report the pharmacologic blockade of voltage-gated sodium ion channels (NaVs) by a synthetic saxitoxin derivative affixed to a photocleavable protecting group. We demonstrate that a functionalized saxitoxin (STX-eac) enables exquisite spatiotemporal control of NaVs to interrupt action potentials in dissociated neurons and nerve fiber bundles. The photo-uncaged inhibitor (STX-ea) is a nanomolar potent, reversible binder of NaVs. We use STX-eac to reveal differential susceptibility of myelinated and unmyelinated axons in the corpus callosum to NaV-dependent alterations in action potential propagation, with unmyelinated axons preferentially showing reduced action potential fidelity under conditions of partial NaV block. These results validate STX-eac as a high precision tool for robust photocontrol of neuronal excitability and action potential generation.


Assuntos
Potenciais de Ação/efeitos dos fármacos , Canal de Sódio Disparado por Voltagem NAV1.2/metabolismo , Saxitoxina/farmacologia , Bloqueadores do Canal de Sódio Disparado por Voltagem/farmacologia , Animais , Axônios/efeitos dos fármacos , Axônios/metabolismo , Células CHO , Células Cultivadas , Corpo Caloso/citologia , Corpo Caloso/efeitos dos fármacos , Corpo Caloso/metabolismo , Cricetulus , Embrião de Mamíferos , Feminino , Hipocampo/citologia , Masculino , Camundongos , Canal de Sódio Disparado por Voltagem NAV1.2/genética , Técnicas de Patch-Clamp , Cultura Primária de Células , Ratos , Ratos Sprague-Dawley , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Saxitoxina/análogos & derivados , Saxitoxina/efeitos da radiação , Análise de Célula Única , Análise Espaço-Temporal , Raios Ultravioleta , Bloqueadores do Canal de Sódio Disparado por Voltagem/efeitos da radiação
9.
Langmuir ; 37(28): 8577-8584, 2021 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-34219459

RESUMO

Using two types of colloidal particles having natural origins to synergistically stabilize Pickering emulsions is essential for food, cosmetics, and pharmaceutics, especially when neither particle can stabilize the Pickering emulsions alone. The use of two natural stabilizers avoids the complicated surface treatments of particles and the introduction of poisonous or harmful chemicals. In this work, we report an all-natural Pickering emulsion stabilized synergistically by starch nanocrystals and zein protein nanoparticles. Our result shows that the electrostatic interaction between the two types of particles greatly affects their assembled structure at the oil/water interface, which is closely related to the emulsion stability. Specifically, particle bilayers could form with oppositely charged particles at the interface to endow the emulsion with improved stability. As a demonstration, the resultant Pickering emulsions effectively carry ß-carotene and have high stability against high temperatures and ultraviolet radiation. This type of all-natural Pickering emulsion is a promising tool to protect and deliver liposoluble bioactive components.


Assuntos
Nanopartículas , Zeína , Emulsões , Tamanho da Partícula , Amido , Raios Ultravioleta
10.
Langmuir ; 37(28): 8445-8454, 2021 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-34236192

RESUMO

As the most frequently used archival materials for painting and recording, paper lays the groundwork for the development of prosperous human civilization. However, its susceptibility to three primary factors including external ultraviolet light, increased acidity, and biological pathogens in long-term storage shortens the longevity of paper. Therefore, the protection of paper-based cultural relics is extremely urgent. Inspired by the three adverse factors affecting the protection of cultural relics, we herein propose to combine the ultraviolet absorber 2-hydroxy-4-(octyloxy)benzophenone (UV-531) and alkaline zinc oxide (ZnO) nanoparticles innovatively into the antibacterial agent polyhexamethylene biguanidine hydrochloride (PHMB) to realize the strategy of three birds with one stone for relics protection. This study illustrates that the tensile strength and the folding endurance of different test papers are guaranteed by coating them with the composite reagents, and molds including Mucor, Trichoderma, and Aspergillus niger are effectually sterilized. In addition, a hand-painted Chinese ink-wash painting with beautiful flowers is chosen as the object for simulating cultural relics protection, and negligible color fading is observed in aging experiments. From the perspective of effectiveness, simplicity, and economy, this strategy sheds light on preservative protection of paper-based relics in long-term storage.


Assuntos
Nanopartículas , Óxido de Zinco , Antibacterianos , Humanos , Raios Ultravioleta/efeitos adversos
11.
Nat Commun ; 12(1): 4416, 2021 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-34285220

RESUMO

In multicellular organisms, expression profiling in spatially defined regions is crucial to elucidate cell interactions and functions. Here, we establish a transcriptome profiling method coupled with photo-isolation chemistry (PIC) that allows the determination of expression profiles specifically from photo-irradiated regions of interest. PIC uses photo-caged oligodeoxynucleotides for in situ reverse transcription. PIC transcriptome analysis detects genes specifically expressed in small distinct areas of the mouse embryo. Photo-irradiation of single cells demonstrated that approximately 8,000 genes were detected with 7 × 104 unique read counts. Furthermore, PIC transcriptome analysis is applicable to the subcellular and subnuclear microstructures (stress granules and nuclear speckles, respectively), where hundreds of genes can be detected as being specifically localised. The spatial density of the read counts is higher than 100 per square micrometre. Thus, PIC enables high-depth transcriptome profiles to be determined from limited regions up to subcellular and subnuclear resolutions.


Assuntos
Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica no Desenvolvimento , Análise Espacial , Transcriptoma/genética , Animais , Encéfalo/crescimento & desenvolvimento , Embrião de Mamíferos , Estudos de Viabilidade , Técnicas Genéticas , Células HeLa , Humanos , Masculino , Camundongos , Células NIH 3T3 , Oligodesoxirribonucleotídeos/química , Oligodesoxirribonucleotídeos/genética , Oligodesoxirribonucleotídeos/efeitos da radiação , Transcrição Reversa/efeitos da radiação , Transcriptoma/efeitos da radiação , Raios Ultravioleta
12.
Environ Monit Assess ; 193(8): 513, 2021 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-34302548

RESUMO

The present analysis deals with the ability of Thermomyces lanuginosus to degrade pre-treated low-density polyethylene (LDPE). The synergistic effect of UV irradiation, heat, and acid pre-treatments on the biodegradability of the polymer was thoroughly assessed. Oxidative structural modifications such as the appearance of carboxylate and carbonyl groups in LDPE chains were recorded post the UV and heat treatments. Furthermore, the nitric acid treatment incorporated NO2 groups into the polymer matrix. Alterations in the polymer thermal stabilities and surface morphologies after each pre-treatment were analyzed using thermogravimetric analysis and scanning electron microscopy (SEM), respectively. The gravimetric analysis revealed a reduction in the weight of the pre-treated LDPE films by 9.21 ± 0.84% after 1 month of the incubation period with Thermomyces lanuginosus. An increase in the thermal stability, disappearance of the incorporated hydrophilic functional groups, and reduction in the carbon content of the polymer samples post the incubation period further justified the biodegradation process. SEM analysis showed modifications in the morphology and texture patterns in pre-treated LDPE after inoculation with Thermomyces lanuginosus. The findings suggest that Thermomyces lanuginosus could be efficient for the decomposition of pre-treated LDPE under laboratory conditions.


Assuntos
Monitoramento Ambiental , Polietileno , Biodegradação Ambiental , Eurotiales , Raios Ultravioleta
13.
Huan Jing Ke Xue ; 42(8): 3847-3857, 2021 Aug 08.
Artigo em Chinês | MEDLINE | ID: mdl-34309271

RESUMO

As an emerging advanced oxidation technology, UV/chlorine treatment is capable of effectively oxidizing various organic pollutants. Till now, the transformation of dissolved effluent organic matter (dEfOM) in real wastewater during UV/chlorine treatment remains unclear. In this study, ultraviolet and fluorescence spectroscopy were combined with Fourier transform ion cyclotron resonance mass spectrometry to probe the transformation of dEfOM in two municipal secondary effluents during UV/chlorine treatment. Meanwhile, the newly formed chlorinated byproducts (Cl-BPs) are particularly concerned. Generally, aromatic compounds and fluorescent components could be readily removed after UV/chlorine treatment, and most of the dEfOM underwent transformation rather than mineralization. Protein-like components, which accounted for the largest proportion of fluorescent components, were subject to a preferential reaction. UV/chlorine treatment could result in the degradation of CHOS compounds and the formation of CHO compounds. During this process, unsaturated and reduced compounds of large molecules were preferentially removed, whereas saturated and oxidized compounds with low molecular weight were produced. Moreover, the concentrations of trihalomethanes and haloacetic acids increased substantially after UV/chlorine treatment. In total, 255 and 133 Cl-BPs were detected in the respective effluents after UV/chlorine treatment. In addition, 12 and 43 possible precursor-Cl-BPs pairs were identified, respectively, based on electrophilic substitution and addition reactions by means of mass difference analysis. This study is expected to provide fundamental information for practical application of the UV/chlorine treatment process.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Cloro/análise , Desinfecção , Trialometanos , Raios Ultravioleta , Águas Residuárias , Poluentes Químicos da Água/análise
14.
Int J Mol Sci ; 22(13)2021 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-34202795

RESUMO

It is a significant challenge for a titanium implant, which is a bio-inert material, to recruit osteogenic factors, such as osteoblasts, proteins and blood effectively when these are contained in a biomaterial. The objective of this study was to examine the effect of ultraviolet (UV)-treatment of titanium on surface wettability and the recruitment of osteogenic factors when they are contained in an atelocollagen sponge. UV treatment of a dental implant made of commercially pure titanium was performed with UV-light for 12 min immediately prior to the experiments. Superhydrophilicity on dental implant surfaces was generated with UV-treatment. The collagen sponge containing blood, osteoblasts, or albumin was directly placed on the dental implant. Untreated implants absorbed only a little blood from the collagen sponge, while the UV-treated implants absorbed blood rapidly and allowed it to spread widely, almost over the entire implant surface. Blood coverage was 3.5 times greater for the UV-treated implants (p < 0.001). Only 6% of the osteoblasts transferred from the collagen sponge to the untreated implants, whereas 16% of the osteoblasts transferred to the UV-treated implants (p < 0.001). In addition, a weight ratio between transferred albumin on the implant and measured albumin adsorbed on the implant was 17.3% in untreated implants and 38.5% in UV-treated implants (p < 0.05). These results indicated that UV treatment converts a titanium surface into a superhydrophilic and bio-active material, which could recruite osteogenic factors even when they were contained in a collagen sponge. The transfer and subsequent diffusion and adsorption efficacy of UV-treated titanium surfaces could be useful for bone formation when titanium surfaces and osteogenic factors are intervened with a biomaterial.


Assuntos
Materiais Biocompatíveis , Colágeno , Osteogênese , Titânio , Raios Ultravioleta , Adsorção , Albuminas , Animais , Materiais Biocompatíveis/química , Colágeno/química , Implantes Dentários , Difusão , Interações Hidrofóbicas e Hidrofílicas , Osseointegração , Osteoblastos/citologia , Osteoblastos/metabolismo , Propriedades de Superfície , Titânio/química , Molhabilidade
15.
Anal Chem ; 93(27): 9462-9470, 2021 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-34192872

RESUMO

Ultraviolet photodissociation (UVPD) has been shown to produce extensive structurally informative data for a variety of chemically diverse compounds. Herein, we demonstrate the performance of the 193 nm UVPD fragmentation technique on structural/moiety characterization of 14 singly charged agrochemicals. Two-dimensional mass spectrometry (2DMS) using infrared multiphoton dissociation (IRMPD) and electron-induced dissociation (EID) have previously been applied to a select range of singly charged pesticides. The ≥80% moiety coverage achieved for the majority of the species by the UVPD and 2D-UVPD methods was on par with and, in some cases, superior to the data obtained by other fragmentation techniques in previous studies, demonstrating that UVPD is viable for these types of species. A three-dimensional (3D) peak picking method was implemented to extract the data from the 2DMS spectrum, overcoming the limitations of the line extraction method used in previous studies, successfully separating precursor specific fragments with milli-Dalton accuracy. Whole spectrum internal calibration combined with 3D peak picking obtained sub-part-per-million (ppm) to part-per-billion (ppb) mass accuracies across the entire 2DMS spectrum.


Assuntos
Agroquímicos , Elétrons , Espectrometria de Massas , Raios Ultravioleta
16.
Molecules ; 26(13)2021 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-34201778

RESUMO

TiO2 nanopowders modified by Nd and Sm were prepared using the sol-gel technique. It was found by XRD analysis that the samples containing Sm are amorphous up to 300 °C, while those with Nd preserve a mixed organic-inorganic amorphous structure at higher temperatures (400 °C). The TiO2 (rutile) was not detected up to 700 °C in the presence of both modified oxides. TiO2 (anatase) crystals found at about 400 °C in the Sm-modified sample exhibited an average crystallite size of about 25-30 nm, while doping with Nd resulted in particles of a lower size-5-10 nm. It was established by DTA that organic decomposition is accompanied by significant weight loss occurring in the temperature range 240-350 °C. Photocatalytic tests showed that the samples heated at 500 °C possess photocatalytic activity under UV irradiation toward Malachite green organic dye. Selected compositions exhibited good antimicrobial activity against E. coli K12 and B. subtilis.


Assuntos
Géis/química , Neodímio/química , Pós/química , Samário/química , Titânio/química , Bacillus subtilis/efeitos dos fármacos , Catálise , Escherichia coli/efeitos dos fármacos , Temperatura Alta , Transição de Fase , Corantes de Rosanilina/química , Análise Espectral , Titânio/efeitos da radiação , Raios Ultravioleta , Difração de Raios X
17.
Int J Mol Sci ; 22(12)2021 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-34207557

RESUMO

Nucleotide excision repair (NER) is the most versatile DNA repair pathway, which can remove diverse bulky DNA lesions destabilizing a DNA duplex. NER defects cause several autosomal recessive genetic disorders. Xeroderma pigmentosum (XP) is one of the NER-associated syndromes characterized by low efficiency of the removal of bulky DNA adducts generated by ultraviolet radiation. XP patients have extremely high ultraviolet-light sensitivity of sun-exposed tissues, often resulting in multiple skin and eye cancers. Some XP patients develop characteristic neurodegeneration that is believed to derive from their inability to repair neuronal DNA damaged by endogenous metabolites. A specific class of oxidatively induced DNA lesions, 8,5'-cyclopurine-2'-deoxynucleosides, is considered endogenous DNA lesions mainly responsible for neurological problems in XP. Growing evidence suggests that XP is accompanied by defective mitophagy, as in primary mitochondrial disorders. Moreover, NER pathway is absent in mitochondria, implying that the mitochondrial dysfunction is secondary to nuclear NER defects. In this review, we discuss the current understanding of the NER molecular mechanism and focuses on the NER linkage with the neurological degeneration in patients with XP. We also present recent research advances regarding NER involvement in oxidative DNA lesion repair. Finally, we highlight how mitochondrial dysfunction may be associated with XP.


Assuntos
Reparo do DNA , Doenças Neurodegenerativas , Raios Ultravioleta/efeitos adversos , Xeroderma Pigmentoso , Humanos , Mitocôndrias/genética , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Doenças Neurodegenerativas/genética , Doenças Neurodegenerativas/metabolismo , Doenças Neurodegenerativas/patologia , Doenças Neurodegenerativas/terapia , Xeroderma Pigmentoso/genética , Xeroderma Pigmentoso/metabolismo , Xeroderma Pigmentoso/patologia
18.
Int J Mol Sci ; 22(12)2021 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-34208711

RESUMO

We report absolute photoabsorption cross sections for gas-phase 2- and 5-bromopyrimidine in the 3.7-10.8 eV energy range, in a joint theoretical and experimental study. The measurements were carried out using high-resolution vacuum ultraviolet synchrotron radiation, with quantum chemical calculations performed through the nuclear ensemble approach in combination with time-dependent density functional theory, along with additional Franck-Condon Herzberg-Teller calculations for the first absorption band (3.7-4.6 eV). The cross sections of both bromopyrimidines are very similar below 7.3 eV, deviating more substantially from each other at higher energies. In the 7.3-9.0 eV range where the maximum cross-section is found, a single and broad band is observed for 5-bromopyrimidine, while more discernible features appear in the case of 2-bromopyrimidine. Several π* ← π transitions account for the most intense bands, while weaker ones are assigned to transitions involving the nitrogen and bromine lone pairs, the antibonding σ*Br orbital, and the lower-lying Rydberg states. A detailed comparison with the available photo-absorption data of bromobenzene is also reported. We have found significant differences regarding the main absorption band, which is more peaked in bromobenzene, becoming broader and shifting to higher energies in both bromopyrimidines. In addition, there is a significant suppression of vibrational structures and of Rydberg states in the pair of isomers, most noticeably for 2-bromopyrimidine.


Assuntos
Modelos Teóricos , Pirimidinas/química , Espectrofotometria Ultravioleta , Raios Ultravioleta , Modelos Moleculares , Estrutura Molecular , Fenômenos Físicos
19.
Int J Mol Sci ; 22(12)2021 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-34208782

RESUMO

This paper concerns the physicochemical properties of chitosan/phenolic acid thin films irradiated by ultraviolet radiation with wavelengths between 200 and 290 nm (UVC) light. We investigated the preparation and characterization of thin films based on chitosan (CTS) with tannic (TA), caffeic (CA) and ferulic acid (FA) addition as potential food-packaging materials. Such materials were then exposed to the UVC light (254 nm) for 1 and 2 h to perform the sterilization process. Different properties of thin films before and after irradiation were determined by various methods such as Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), atomic force microscopy (AFM), differential scanning calorimeter (DSC), mechanical properties and by the surface free energy determination. Moreover, the antimicrobial activity of the films and their potential to reduce the risk of contamination was assessed. The results showed that the phenolic acid improving properties of chitosan-based films, short UVC radiation may be used as sterilization method for those films, and also that the addition of ferulic acid obtains effective antimicrobial activity, which have great benefit for food packing applications.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Quitosana/química , Hidroxibenzoatos/química , Raios Ultravioleta , Aderência Bacteriana/efeitos dos fármacos , Varredura Diferencial de Calorimetria , Fenômenos Químicos , Fenômenos Mecânicos , Testes de Sensibilidade Microbiana , Microscopia de Força Atômica , Espectroscopia de Infravermelho com Transformada de Fourier
20.
Sensors (Basel) ; 21(14)2021 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-34300394

RESUMO

The aim of the present study was to evaluate the relative attenuation of VIS, UV and NIR solar radiation through a large pond skylight into the interior of the l'Almoina Archaeological Museum (Valencia, Spain), and to determine how relative attenuation varied throughout the year and time of day. Measurements were taken at 9:00 a.m., 12:00 p.m. and 3:00 p.m. during July 2019 and January 2020. Relative attenuation values were obtained from the measurement of spectral irradiance in the exterior and at different points in the interior by means of two Ocean Optics spectrometers: HR4000CG-UV-NIR for VIS (400-700 nm) and NIR (700-1000 nm) bands, and FLAME-S-UV-VIS for UV-A (280-315 nm) and UV-A (315-400 nm) bands. The central points of the skylight had relative attenuation at 520 nm, reaching a value of 50% in summer at noon and 38% in the afternoon. At noon in winter, there were two relative attenuation peaks above 33% at 520 nm and at 900 nm. For mean relative attenuation, in the UVB range, the highest relative attenuation (20%) was inside the ruins in the morning in both summer and winter, and the UVA band relative attenuation was quite constant throughout the museum, but lower than that of the UVB band, in the range 0-3%.


Assuntos
Energia Solar , Raios Ultravioleta , Arqueologia , Estações do Ano , Espanha
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