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1.
Dermatology ; : 1-9, 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38852575

RESUMO

INTRODUCTION: Despite numerous treatment options for nail lichen planus (NLP), a validated method for measuring the severity of NLP and therapeutic response in clinical trials is absent. The aim of the study was to develop and validate a measurement instrument, Typical Nail Lichen Planus Severity Index (tNLPSI), for typical NLP that could be used in clinical trials. METHODS: A total of 48 patients pathologically confirmed with typical NLP were enrolled in this study. Five dermatologists were trained to use the tNLPSI activity scale and the Physician's Global Assessment (PGA) scale to score samples independently to estimate inter-rater and intra-rater reliability across two sessions. In addition, tNLPSI activity scores were compared with PGA scores to assess the construct validity. RESULTS: The tNLPSI activity scale had excellent internal consistency and inter-rater reliability (Cronbach's alpha 0.990; ICC = 0.954; 95% CI = 0.930-0.971), and the correlations between the different graders' scores indicate good consistency (rp = 0.934-0.968). In addition, the tNLPSI activity scale demonstrated high intra-rater reliability (ICC = 0.996; 95% CI = 0.993-0.998), showing good reproducibility. And tNLPSI activity scores and PGA scores showed good construct validity (Spearman's rho = 0.941 and Spearman's rho = 0.903-0.935, respectively; p < 0.01). CONCLUSION: The tNLPSI activity scale was demonstrated to be consistent, reliable, reproducible, and feasible, making it a potential valuable tool for evaluating the treatment response in typical NLP clinical trials.

2.
Inorg Chem ; 61(18): 7143-7152, 2022 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-35485212

RESUMO

Metal halide perovskites have flexible crystal and electronic structures and adjustable emission characteristics, which have very broad applications in the optoelectronic field. Among them, all-inorganic perovskites have attracted more attention than others in recent years because of their characteristics of large diffusion length, high luminescence efficiency, and good stability. In this work, Sb3+-doped RbCdCl3 crystalline powder was synthesized by a simple hydrothermal method, and its luminescence properties were studied, which showed a broad emission band with a large Stokes shift and efficient yellow light emission at about 596 nm at room temperature with a photoluminescence quantum yield of 91.7%. The emission came from the transition of the self-trapped exciton 1 (STE1) out of 3Pn (n = 0, 1, and 2) to S0 due to strong electron-phonon coupling, which scaled with increasing temperature. Moreover, its emission color became white at low temperatures due to the occurrence of transition of other self-trapped exciton 0 (STE0) state emission out of the 1S states of Sb ions to S0 in the lattice. These emission color changes may be used for temperature sensing, and this Sb3+-doped RbCdCl3 material expands the knowledge of the efficient luminescent inorganic material family for further applications of all-inorganic perovskites.

3.
Inorg Chem ; 61(31): 12406-12414, 2022 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-35877167

RESUMO

Lead-based metal halide perovskites have received widespread attention for their promising application prospects in the field of lighting and display due to their excellent optical properties. However, the toxicity of lead may hinder their further commercial application. Herein, a zero-dimensional (0D) metal halide (NH4)2InCl5·H2O with an orthorhombic structure and the Pnma space group was produced. With doping with Sb3+, these products exhibit one highly efficient and wide yellow emission band (∼450-850 nm) in their photoluminescence (PL) spectra, which covers almost the entire visible spectral range at room temperature; however, they give two emission bands with long decay lifetimes (microseconds) at low temperature. Temperature-dependent steady-state PL, transient PL spectroscopy, temperature-dependent Raman spectra characterization, and theoretical band structure calculations confirm that the dual-band emission at low temperature originates from the dual vibronic levels of the self-trapped exciton (STE) in the hole-vibration state, whose vibration energy is related to the H2O-NH4+ connection in the valence band. This result proves that the vibronic state in STE formation involves both electrons and holes in the excited states, the opposite of this happens in the electron-vibration band in most perovskite halides. These results provide new insight into the luminescent mechanism of Sb3+ in halide perovskites, especially used for emission color modulation by the temperature-dependent electron- or hole-vibration processes.

4.
World J Microbiol Biotechnol ; 38(12): 228, 2022 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-36149606

RESUMO

Melanin is a secondary metabolite composed of complex heterogeneous polymers. Fungal melanin is considered to be a sustainable and biodegradable natural pigment and has a variety of functional properties and biological activities. On one hand, due to its own specific properties it can play the role of antioxidant, anti-radiation, adsorption, and photoprotection. On the other hand, it has good biological activities such as hepatoprotective effect, hypolipidemic effect and anti-cancer. Therefore, it is widely used in various fields of daily life, including dyeing, food, biomedical and commercial industry. It is conducive to environmental protection and human health. However, the insolubility of fungal melanin in water, acids and organic solvents has been an obstacle to its commercial applications. Thus, the chemical modification methods of fungal melanin are summarized to increase its solubility and expand the application fields. Although fungal melanin has been used in many industries, as the structure and function of fungal melanin and modified melanin are further studied, more functional properties and bioactivities are expected to be discovered for a wide range of applications in the future.


Assuntos
Antioxidantes , Melaninas , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Fungos/metabolismo , Humanos , Melaninas/química , Polímeros/metabolismo , Solventes , Água/metabolismo
5.
Angew Chem Int Ed Engl ; 61(45): e202210487, 2022 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-36117387

RESUMO

T lymphocytes (T cells) are essential for tumor immunotherapy. However, the insufficient number of activated T cells greatly limits the efficacy of tumor immunotherapy. Herein, we proposed an oncolytic virus-mimicking strategy to enhance T cell recruitment and activation for tumor treatment. We constructed an oncolytic virus-like nanoplatform (PolyIC@ZIF-8) that was degraded in the acidic tumor environment to release PolyIC and Zn2+ . The released PolyIC exhibited an oncolytic virus-like function that induced tumor cell apoptosis and promoted T cell recruitment and activation through a tumor antigen-dependent manner. More importantly, the released Zn2+ not only enhanced T cell recruitment by inducing CXCL9/10/11 expression but also promoted T cell activation to increase interferon-γ (INF-γ) expression by inducing the phosphorylation of ZAP-70 via a tumor antigen-independent manner. This Zn2+ -enhanced oncolytic virus-mimicking strategy provides a new approach for tumor immunotherapy.


Assuntos
Nanopartículas , Neoplasias , Terapia Viral Oncolítica , Vírus Oncolíticos , Humanos , Vírus Oncolíticos/metabolismo , Imunoterapia , Neoplasias/terapia , Antígenos de Neoplasias , Linhagem Celular Tumoral
6.
Nano Lett ; 20(4): 2522-2529, 2020 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-32208714

RESUMO

Photothermal therapy (PTT) is an efficient approach for cancer treatment. However, accurately monitoring the spatial distribution of photothermal transducing agents (PTAs) and mapping the real-time temperature change in tumor and peritumoral normal tissue remain a huge challenge. Here, we propose an innovative strategy to integrate T1-MRI for precisely tracking PTAs with magnetic resonance temperature imaging (MRTI) for real-time monitoring temperature change in vivo during PTT. NaBiF4: Gd@PDA@PEG nanomaterials were synthesized with favorable T1-weighted performance to target tumor and localize PTAs. The extremely weak susceptibility (1.04 × 10-6 emu g-1 Oe1-) of NaBiF4: Gd@PDA@PEG interferes with the local phase marginally, which maintains the capability of MRTI to dynamically record real-time temperature change in tumor and peritumoral normal tissue. The time resolution is 19 s per frame, and the detection precision of temperature change is approximately 0.1 K. The approach achieving PTT guided by multimode MRI holds significant potential for the clinical application.


Assuntos
Imageamento por Ressonância Magnética/métodos , Nanoestruturas/análise , Neoplasias/terapia , Terapia Fototérmica/métodos , Termografia/métodos , Animais , Bismuto/análise , Gadolínio/análise , Camundongos , Neoplasias/diagnóstico por imagem , Fluoreto de Sódio/análise , Temperatura
7.
Biochem Biophys Res Commun ; 524(3): 567-574, 2020 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-32019674

RESUMO

Hypereosinophilic syndrome (HES) is a rare multisystem disease that predominantly includes skin with severe and persistent itching. A lack of understanding about the pathological condition and mechanism of dermatosis caused by HES hinders its treatment. In the present study, we applied a quantitative proteomics approach to characterize the cellular responses of skin tissue to idiopathic HES (IHES) at the proteome level. We identified hundreds of skin tissue proteins that were differentially expressed between IHES patients and healthy individuals. IHES patients display severely damaged microenvironment, including extracellular matrix (ECM) organization and disassembly, immune disorders, decreased metabolic capacity, and susceptibility to microbial infection. Moreover, there was abnormal proliferation of basal epidermal stem cells, which was closely related to high expression of the epigenetic regulator, histone deacetylase 2, providing mechanistic insight into the abnormal epidermal thickening of IHES skin tissues. Overall, our study provides a comprehensive framework for a system-level understanding of IHES-induced dermatosis (IHESiD) tissues at the protein and cell pathway levels. Our findings may facilitate a new approach to diagnosis and treatment to alleviate skin clinical symptoms, monitor the activity of IHES, and determine therapeutic effects.


Assuntos
Síndrome Hipereosinofílica/patologia , Pele/patologia , Biologia de Sistemas , Proliferação de Células , Regulação para Baixo , Epiderme/patologia , Histona Desacetilase 2/metabolismo , Humanos , Espectrometria de Massas , Proteômica , Células-Tronco/patologia
8.
Skin Res Technol ; 26(4): 494-502, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31811677

RESUMO

PURPOSE: We aimed to summarize the sensitivity and specificity between RCM and dermoscopy in LM diagnosis. METHODS: A meta-analysis was conducted to the study. PubMed, Google Scholar, Cochrane Library, and Wiley Online Library database were searched for relevant studies. The basic information of the patients, sensitivity, and specificity were calculated. I2 was used for the assessment of the heterogeneity. A random-effect model was used for analyzing the data of the literature study. RESULTS: A total of 498 patients from 7 articles were included in the study. The articles summarized the sensitivity and specificity between RCM and dermoscopy in the treatment of lentigo maligna. The overall sensitivity of RCM was 0.93, and the overall specificity was 0.89. RCM diagnostic odds ratio (DOR) was 104.38, RCM positive likelihood (+LR/PLR) was 8.50, and the negative LR (-LR/NLR) was 0.08. The overall sensitivity of dermoscopy was 0.73 (95% CI: 0.58-0.84), and the overall specificity was 0.84 (95% CI: 0.71-0.92). The DOR, +LR, and -LR of dermoscopy were 14.48, 4.65, and 0.32, respectively. CONCLUSION: RCM has a better accuracy than dermoscopy in the diagnosis of LM.


Assuntos
Sarda Melanótica de Hutchinson , Neoplasias Cutâneas , Dermoscopia , Humanos , Sarda Melanótica de Hutchinson/diagnóstico por imagem , Microscopia Confocal , Ensaios Clínicos Controlados Aleatórios como Assunto , Sensibilidade e Especificidade , Neoplasias Cutâneas/diagnóstico por imagem
9.
Lasers Surg Med ; 52(8): 761-767, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-31919885

RESUMO

BACKGROUND AND OBJECTIVES: Alopecia areata (AA) is an autoimmune disease characterized by T cell-mediated attack on the hair follicle. Although there are a wide range of therapies, the majority of them are not satisfactory due to side effects or limited efficacy. In this study, we sought to evaluate the efficacy, influence factors, and safety of 308-nm excimer lamp with minoxidil in the treatment of AA. STUDY DESIGN/MATERIALS AND METHODS: This was a prospective, single-blinded, self-control study, using 308-nm excimer lamp with minoxidil for the treatment of AA. One selected alopecia lesion was divided into the control and treated side. Topical minoxidil (2% solution) was used on both sides, but 308-nm excimer lamp was only added to the treated side. The primary endpoint was the discrepancy of hair growth on each side. RESULTS: A total of 38 patients (24 males and 14 females) with AA were enrolled in this study, and 34 of them (21 males and 13 females) completed the whole treatment. Thirty-two (94.2%) patients achieved clinical response, and 21 (44.1%) patients achieved with >50% hair regrowth on the treated side after a 12-week treatment. The hair number and diameter on the treated side had significantly increased compared with the control side with statistical differences. Hyperpigmentation and erythema occurred on the treated side of all the patients but they were considered tolerable. Patients of younger age or with smaller area of lesion had better effect. CONCLUSIONS: The 308-nm excimer lamp with minoxidil therapy can be considered as an effective and safe treatment for single or multiple AA. Lasers Surg. Med. © 2020 Wiley Periodicals, Inc.


Assuntos
Alopecia em Áreas , Minoxidil , Alopecia , Alopecia em Áreas/diagnóstico por imagem , Alopecia em Áreas/tratamento farmacológico , Feminino , Cabelo , Humanos , Lasers de Excimer , Masculino , Estudos Prospectivos , Resultado do Tratamento
10.
Angew Chem Int Ed Engl ; 59(47): 21032-21040, 2020 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-32667130

RESUMO

Free radicals with reactive chemical properties can fight tumors without causing drug resistance. Reactive oxygen species (ROS) has been widely used for cancer treatment, but regrettably, the common O2 and H2 O2 deficiency in tumors sets a severe barrier for sufficient ROS production, leading to unsatisfactory anticancer outcomes. Here, we construct a chlorine radical (. Cl) nano-generator with SiO2 -coated upconversion nanoparticles (UCNPs) on the inside and Ag0 /AgCl hetero-dots on the outside. Upon near-infrared (NIR) light irradiation, the short-wavelength emission UCNP catalyzes . Cl generation from Ag0 /AgCl with no dependence on O2 /H2 O2 . . Cl with strong oxidizing capacity and nucleophilicity can attack biomolecules in cancer cells more effectively than ROS. This . Cl stress treatment will no doubt broaden the family of oxidative stress-induced antitumor strategies by using non-oxygen free radicals, which is significant in the development of new anticancer agents.


Assuntos
Antineoplásicos/farmacologia , Cloro/farmacologia , Radicais Livres/farmacologia , Fármacos Fotossensibilizantes/farmacologia , Animais , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cloro/química , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Radicais Livres/química , Raios Infravermelhos , Neoplasias Mamárias Experimentais/tratamento farmacológico , Neoplasias Mamárias Experimentais/metabolismo , Neoplasias Mamárias Experimentais/patologia , Camundongos , Nanopartículas/química , Estresse Oxidativo/efeitos dos fármacos , Tamanho da Partícula , Fármacos Fotossensibilizantes/química , Dióxido de Silício/química , Dióxido de Silício/farmacologia , Prata/química , Prata/farmacologia , Propriedades de Superfície
11.
Small ; 15(5): e1803468, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30624027

RESUMO

Metal-organic frameworks (MOFs) provide intriguing platforms for the design of responsive materials. It is challenging to mobilize as many components as possible of a MOF to collaboratively accomplish multiple responsive properties. Here, reversible photochromism, piezochromism, hydrochromism, ionochromism, and luminescence modulation of an ionic Eu(III) MOF is reported furnished by cationic electron-deficient viologen units and exchangeable guest anions. Mechanistically, the extraordinarily versatile responsive properties are owed to electron transfer (ET), charge transfer (CT), and energy transfer, involving viologen as electron acceptor, anion as electron donor, luminescing Eu(III) as energy donor, and anion-viologen CT complex or ET-generated radical as energy acceptor (luminescence quencher). Moreover, guest anions and waters provide flexible handles to control the ET-based responsive properties. Water release/reuptake or exchange with organic solvents can switch on/off the response to light, while reversible anion exchange can disenable or awaken the responses to pressure, light, and water release/reuptake. The impacts of water and anions on ET are justified by the high polarity and hydrogen-bonding capability of water, the different electron donor strength of anions, and the strong I- -viologen CT interactions. The rich responsive behaviors have great implications for applications such as pressure sensors, iodide detection, and chemical logic gates.

12.
J Cutan Med Surg ; 23(4): 370-379, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31010295

RESUMO

BACKGROUND: 5-aminolevulinic acid photodynamic therapy (PDT) for genital warts is effective, safe, and can prevent recurrence. It is believed that PDT can induce immune responses, but the mechanism is not completely understood. OBJECTIVES: The objectives of this article are to confirm the effect of PDT for genital warts on local immunity and to investigate the recruitment and significance of immune cells in tissues. METHODS: Local immune changes in T lymphocytes (CD3+, CD4+, CD8+), plasmacytoid dendritic cells (pDCs) (CD123+), and myeloid dendritic cells (CD1a+) after PDT in patients were evaluated by immunohistochemistry staining. Changes in mRNA levels of IFN-γ, IFN-α, IFN-ß, interferon-stimulated gene 15 kDa (ISG-15), Mx2, Toll-like receptor 9 (TLR9), and interferon regulatory factor 7 (IRF7) were analyzed by real-time quantitative polymerase chain reaction. RESULTS: At 4 hours after PDT, CD4+ increased, accompanied by increased levels of mRNA expression of IFN-γ, but CD4+ and mRNA expression levels of IFN-γ were decreased at 24 hours after PDT. CD123+ pDCs showed an increasing trend. CD1a+ LCs in the epidermis gradually decreased, and DCs in the epidermis gradually increased. CD3+ infiltrated and migrated to the superficial dermis, but CD8+ did not change significantly after PDT. The mRNA expression levels of IFN-α, IFN-ß, ISG-15, Mx2, TLR9, and IRF7 showed an increasing trend after PDT. As compared with the patients without significantly increased IFN-α and IFN-ß after PDT sessions, patients with significant increases needed fewer sessions of PDT for remission. CONCLUSIONS: PDT for genital warts can activate T lymphocyte-mediated, DC-related, and pDC-related immunity. The clinical efficacy of PDT for genital warts may be related to the increased levels of IFN-α and IFN-ß after treatment.


Assuntos
Ácido Aminolevulínico/farmacologia , Condiloma Acuminado/tratamento farmacológico , Epiderme/imunologia , Células de Langerhans/imunologia , Fotoquimioterapia , Fármacos Fotossensibilizantes/farmacologia , Adulto , Ácido Aminolevulínico/uso terapêutico , Antígenos CD1/metabolismo , Complexo CD3/metabolismo , Contagem de Linfócito CD4 , Linfócitos T CD8-Positivos/imunologia , Citocinas/genética , Epiderme/metabolismo , Feminino , Expressão Gênica/efeitos dos fármacos , Humanos , Fator Regulador 7 de Interferon/genética , Interferon-alfa/genética , Interferon beta/genética , Interferon gama/genética , Subunidade alfa de Receptor de Interleucina-3/metabolismo , Células de Langerhans/efeitos dos fármacos , Células de Langerhans/metabolismo , Masculino , Pessoa de Meia-Idade , Proteínas de Resistência a Myxovirus/genética , Fármacos Fotossensibilizantes/uso terapêutico , RNA Mensageiro/metabolismo , Receptor Toll-Like 9/genética , Ubiquitinas/genética , Adulto Jovem
13.
Small ; 14(37): e1802615, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30117655

RESUMO

SnTe is known as an eco-friendly analogue of PbTe without toxic elements. However, the application potentials of pure SnTe are limited because of its high hole carrier concentration derived from intrinsic Sn vacancies, which lead to a high electrical thermal conductivity and low Seebeck coefficient. In this study, Sn self-compensation and Mn alloying could significantly improve the Seebeck coefficients in the whole temperature range through simultaneous carrier concentration optimization and band engineering, thereby leading to a large improvement of the power factors. Combining precipitates and atomic-scale interstitials due to Mn alloying with dense dislocations induced by long time annealing, the lattice thermal conductivity is drastically reduced. As a result, an enhanced figure of merit (ZT) of 1.35 is achieved for the composition of Sn0.94 Mn0.09 Te at 873 K and the ZTave from 300 to 873 K is boosted to 0.78, which is of great significance for practical application. Hitherto, the ZTmax and ZTave of this work are the highest values among all single-element-doped SnTe systems.

14.
Cell Physiol Biochem ; 43(1): 147-157, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28848158

RESUMO

BACKGROUND/AIMS: Cutaneous melanoma is one of the leading causes of cancer deaths with an increasing incidence worldwide. A KRAB-containing zinc finger protein member, zinc finger 23 (ZNF23), was reduced in some types of tumors and inhibited cell growth by inducing cell cycle arrest. However, the role of ZNF23 expression is still poorly understood in melanoma. METHODS: The level of ZNF23 expression was detected in cutaneous melanoma, adjacent normal skin tissues and cutaneous melanoma cell lines using immunohistochemistry and western blotting. The correlations between ZNF23 expression and other clinicopathologic parameters were analyzed in melanoma patients. Ectopic expression of ZNF23 plasmid was transfected into melanoma cells, SK-MEL-1 and SK-MEL-28. MTT, flow cytometry and transwell assay were used to measure cell proliferation, apoptosis, invasion and migration abilities, respectively. Mitochondrial functions and structures were detected by mitochondrial membrane potential assay and Transmission electron microscopy (TEM) method in melanoma cells transfected with overexpressing ZNF23 plasmid or empty vector. Western blotting was performed to detect the levels of ZNF23, p53, p27, Bcl-2 and cleaved caspase-3 after overexpressing of ZNF23 in melanoma cells. RESULTS: ZNF23 was elevated in adjacent normal skin tissues compared with melanoma tissues. Patients with low level of ZNF23 expression exhibited higher incidence of lymphoid metastasis, thicker size of tumors and worse outcome. By using Cox's regression analysis, ZNF23 expression, tumor thickness and lymph node metastasis were the independent prognostic factors for overall survival (p < 0.05). Results from cellular experiments indicated that ectopic expression of ZNF23 induced cell apoptosis by activation of caspase-3, p27, p53 expression and down-regulation of Bcl-2 through mitochondria-dependent pathway. CONCLUSIONS: Decreased ZNF23 was contributed to melanoma progression and poor survival with mitochondria-dependent pathway. It indicated that ZNF23 could be a promising therapeutic biomarker candidate for cutaneous melanoma.


Assuntos
Melanoma/patologia , Neoplasias Cutâneas/patologia , Fatores de Transcrição/metabolismo , Adolescente , Adulto , Idoso , Apoptose , Caspase 3/metabolismo , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Feminino , Vetores Genéticos/genética , Vetores Genéticos/metabolismo , Humanos , Modelos Logísticos , Metástase Linfática , Masculino , Melanoma/metabolismo , Melanoma/mortalidade , Pessoa de Meia-Idade , Mitocôndrias/metabolismo , Prognóstico , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/mortalidade , Fatores de Transcrição/genética , Proteína Supressora de Tumor p53/metabolismo , Adulto Jovem , Melanoma Maligno Cutâneo
16.
Nat Prod Res ; : 1-10, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38425101

RESUMO

To obtain higher melanin production in liquid culture, culture conditions of Annulohypoxylon stygium (Lév.) Y.M. Ju, J.D. Rogers and H.M. Hsieh were optimised. The results showed that using single factor experiment and orthogonal test, the optimised production of melanin reached 2.20 g/L, which was 2.06 times higher than that of the control group. In addition, it was speculated that A. stygium melanin (AsM) was 3,4-dihydroxyphenylalanine (DOPA) melanin and showed an amorphous irregular structure. Moreover, it had good solubility in alkaline solution. AsM showed good antioxidant activity at a concentration of 500 mg/L, with DPPH, ABTS and OH radicals scavenging activities of 90.83%, 75.36% and 70.90%, respectively. AsM prevented alcohol-induced oxidative damage and oxidative stress in HepG2 cells by inhibiting the decrease of antioxidant key enzyme activity under alcohol stimulation. It was proved to have a great potential for application as a natural antioxidant and a substitute for synthetic pigments.

17.
Materials (Basel) ; 17(8)2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38673276

RESUMO

Bismuth telluride (Bi2Te3)-based alloys have been extensively employed in energy harvesting and refrigeration applications for decades. However, commercially produced Bi2Te3-based alloys using the zone-melting (ZM) technique often encounter challenges such as insufficient mechanical properties and susceptibility to cracking, particularly in n-type Bi2Te3-based alloys, which severely limit the application scenarios for bismuth telluride devices. In this work, we seek to enhance the mechanical properties of n-type Bi2Te2.7Se0.3 alloys while preserving their thermoelectrical performance by a mixed mechanism of grain refinement and the TiN composite phase-introduced pinning effect. These nanoscale processes, coupled with the addition of TiN, result in a reduction in grain size. The pinning effects of nano-TiN contribute to increased resistance to crack propagation. Finally, the TiN-dispersed Bi2Te2.7Se0.3 samples demonstrate increased hardness, bending strength and compressive strength, reaching 0.98 GPa, 36.3 MPa and 74 MPa. When compared to the ZM ingots, those represent increments of 181%, 60% and 67%, respectively. Moreover, the thermoelectric performance of the TiN-dispersed Bi2Te2.7Se0.3 samples is identical to the ZM ingots. The samples exhibit a peak dimensionless figure of merit (ZT) value of 0.957 at 375 K, with an average ZT value of 0.89 within the 325-450 K temperature range. This work has significantly enhanced mechanical properties, increasing the adaptability and reliability of bismuth telluride devices for various applications, and the multi-effect modulation of mechanical properties demonstrated in this study can be applied to other thermoelectric material systems.

18.
RSC Adv ; 13(21): 14131-14138, 2023 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-37180024

RESUMO

Different subtypes of breast cancer (BCC) have variable degrees of malignancy, which is closely related to their extracellular pH (pHe). Therefore, it is increasingly significant to monitor the extracellular pH sensitively to further determine the malignancy of different subtypes of BCC. Here, a l-arginine and Eu3+ assembled nanoparticle Eu3+@l-Arg was prepared to detect the pHe of two breast cancer models (TUBO is non-invasive and 4T1 is malignant) using a clinical chemical exchange saturation shift imaging technique. The experiments in vivo showed that Eu3+@l-Arg nanomaterials could respond sensitively to changes of pHe. In 4T1 models, the CEST signal enhanced about 5.42 times after Eu3+@l-Arg nanomaterials were used to detect the pHe. In contrast, few enhancements of the CEST signal were seen in the TUBO models. This significant difference had led to new ideas for identifying subtypes of BCC with different degrees of malignancy.

19.
Adv Healthc Mater ; 12(31): e2300684, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37714524

RESUMO

Multidrug resistance (MDR) is one of the major factors causing failure of non-small-cell lung cancer (NSCLC) chemotherapy. Real-time and accurate differentiation between drug-resistant and sensitive NSCLC is of primary importance for guiding the subsequent treatments and improving the therapeutic outcome. However, there is no effective method to provide such an accurate differentiation. This study creates an innovative strategy of integrating H2 O2 -responsive nanoprobes with the quantitative T1 -mapping magnetic resonance imaging (MRI) technique to achieve an accurate differential diagnosis between drug-resistant and sensitive NSCLC in light of differences in H2 O2 content in the tumor microenvironment (TME). The result demonstrates that the synthesized MIL-53(Fe)@MnO2 nanocomposites possess an excellent capability of shortening the cancer longitudinal relaxation time (T1 ) when meeting H2 O2 in TME. T1 -mapping MRI could sensitively detect this T1 variation (about 2.6-fold that of T1-weighted imaging (T1 WI)) to accurately differentiate the H2 O2 content between drug-resistant and sensitive NSCLC. In addition, the quantitative data provided by the T1 -mapping MRI dedicates correct comparison across imaging tests and is more reliable than T1 WI, thus giving it a chance for precise assessment of the anti-cancer effect. This innovative strategy of merging TME adaptable nanoprobes with the quantitative MRI technique provides a new approach for the precise diagnosis of multidrug-resistant NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/patologia , Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Carcinoma Pulmonar de Células não Pequenas/patologia , Meios de Contraste , Compostos de Manganês , Diagnóstico Diferencial , Óxidos , Imageamento por Ressonância Magnética/métodos , Microambiente Tumoral
20.
Adv Sci (Weinh) ; 10(34): e2304668, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37870166

RESUMO

Positive computed tomography (CT) contrast nanoagent has significant applications in diagnosing tumors. However, the sensitive differentiation between hepatoma and normal liver tissue remains challenging. This challenge arises primarily because both normal liver and hepatoma tissues capture the nanoagent, resulting in similar positive CT contrasts. Here, a strategy for fusing positive and negative CT contrast nanoagent is proposed to detect hepatoma. A nanoagent Hf-MOF@AB@PVP initially generates a positive CT contrast signal of 120.3 HU in the liver. Subsequently, it can specifically respond to the acidic microenvironment of hepatoma to generate H2 , further achieving a negative contrast of -96.0 HU. More importantly, the relative position between the negative and positive signals area is helpful to determine the location of hepatoma and normal liver tissues. The distinct contrast difference of 216.3 HU and relative orientation between normal liver and tumor tissues are meaningful to sensitively distinguish hepatoma from normal liver tissue utilizing CT imaging.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/diagnóstico por imagem , Neoplasias Hepáticas/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Meios de Contraste , Microambiente Tumoral
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