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1.
Eco Environ Health ; 3(1): 30-44, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38162868

RESUMO

Benzophenone ultraviolet light filters (BPs) are high-production-volume chemicals extensively used in personal care products, leading to widespread human exposure. Given their estrogenic properties, the potential health risks associated with exposure to BPs have become a public health concern. This review aims to summarize sources and pathways of exposure to BPs and associated health risks. Dermal exposure, primarily through the use of sunscreens, constitutes a major pathway for BP exposure. At a recommended application rate, dermal exposure of BP-3 via the application of sunscreens may reach or exceed the suggested reference dose. Other exposure pathways to BPs, such as drinking water, seafood, and packaged foods, contribute minimal to the overall dose. Inhalation is a minor pathway of exposure; however, its contribution cannot be ignored. Human exposure to BPs is an order of magnitude higher in North America than in Asia and Europe. Studies conducted on laboratory animals and cells have consistently demonstrated the toxic effects of BP exposure. BPs are estrogenic and elicit reproductive and developmental toxicities. Furthermore, neurotoxicity, hepatotoxicity, nephrotoxicity, and carcinogenicity have been reported from chronic BP exposure. In addition to animal and cell studies, epidemiological investigations have identified associations between BPs and couples' fecundity and other reproductive disorders, as well as adverse birth outcomes. Further studies are urgently needed to understand the risks posed by BPs on human health.

2.
J Cosmet Dermatol ; 21(3): 1171-1177, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33901342

RESUMO

BACKGROUND: Patients with rosacea often complained of low tolerance to skincare. AIM: To examine if the preexisted low tolerance to skincare is associated with rosacea the occurrence of the Chinese population. METHODS: A retrospective case-control survey of 997 rosacea cases and 1012 skin-healthy controls was carried out in China. Low tolerance to skincare was evaluated based on the history of facial skin allergic reactions related to skincare in the past 5 years before the onset of rosacea. A comparative analysis was performed between the case and control groups by the chi-square test and the logistic regression analysis. RESULTS: History of facial skin allergic reaction due to skin care products (OR = 5.110, 95% CI = 3.893-6.706) and skin care in beauty salons (OR = 3.002, 95% CI = 1.506-5.981) both presented a positive correlations with the occurrence of rosacea. Facial masks and cosmetics were two of the most common products causing facial allergic reaction. The OR values increased with the increased frequency of allergic reactions related to facial mask and cosmetics. In addition, the history of facial skin allergic reaction had a significantly associated with the severity of self-reported symptoms of rosacea including dryness, burning, stinging and itching. CONCLUSIONS: The condition of low tolerance of the facial skin to skincare was closely associated with the occurrence of rosacea.


Assuntos
Rosácea , Estudos de Casos e Controles , China/epidemiologia , Humanos , Estudos Retrospectivos , Rosácea/diagnóstico , Rosácea/epidemiologia , Higiene da Pele/efeitos adversos
3.
Proc Inst Mech Eng H ; 236(1): 103-120, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34617494

RESUMO

Bone cutting plays an important role in spine surgical operations. The power devices with high speed employing in bone cutting usually leads to high cutting temperature of the bone tissue. This high temperature control is important in improving cutting surface quality and optimizing the cutting parameters. In this paper, the bone-cutting model was appropriately simplified for finite element (FE) based modeling of 2D orthogonal cutting to discuss the change law of cutting temperature of cortical bones for cervical vertebra, and to study the orthogonal cutting mechanism of the anisotropic cortical bone, a 3D FE simulation model had been also established in which longitudinal, vertical, and transversal cutting types were accomplished to investigate the effect of osteons orientation. Secondly, this response surface method was used to regress the simulation results, and establishes the prediction model of maximum temperature on cutting depth, cutting speed, and feed speed. Then, the Sobol method was used to analyze the sensitivity of the milling temperature prediction mathematical model parameters, in order to clarify and quantitatively analyze the influence of input milling parameters on the output milling temperature. Finally, the cutting temperatures obtained with the simulations were compared with the corresponding experimental results obtained from the bone milling tests. This study verifies the influence of key variables and the cutting parameters on thermo mechanical behavior of the bone cutting. The obtained cutting temperature distribution for the bone surfaces could be employed to establish a theoretical foundation for research on thermal damage control of bone tissues.


Assuntos
Procedimentos Ortopédicos , Osso e Ossos/cirurgia , Osso Cortical/cirurgia , Temperatura Alta , Temperatura
4.
Cancer Biother Radiopharm ; 36(1): 18-22, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31702382

RESUMO

Background: LncRNA LINC00974 participates in oral fibrogenesis, indicating possible involvement in other oral diseases. Results: The authors found that LINC00974 was upregulated in oral squamous cell carcinoma (OSCC) and predicted poor survival. In OSCC tissues, LINC00974 was inversely correlated with miR-122 and positively correlated with RhoA. In OSCC cells, LINC00974 overexpression resulted in upregulated, whereas overexpression of miR-122 led to downregulated RhoA. Moreover, downregulated miR-122 was observed after LINC00974 overexpression, whereas LINC00974 expression was not significantly affected by miR-122 overexpression. In invasion and migration assay, miR-122 overexpression resulted in reduced, whereas LINC00974 and RhoA overexpression resulted in increased rate of cancer cell migration and invasion. In addition, miR-122 overexpression reduced the effects of LINC00974 overexpression. Conclusion: Therefore, LINC00974 can downregulate miR-122 to upregulate RhoA in OSCC, thereby promoting cell invasion and migration.


Assuntos
MicroRNAs/metabolismo , Neoplasias Bucais/genética , RNA Longo não Codificante/metabolismo , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Proteína rhoA de Ligação ao GTP/genética , Adulto , Idoso , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/patologia , Invasividade Neoplásica/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Regulação para Cima
5.
J Mass Spectrom ; 56(4): e4539, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32677755

RESUMO

In this study, we developed contactless electrospray ionization mass spectrometry (ESI-MS) for in vivo analysis of living organisms in different applications. The in vivo sampling and direct analysis processess of living organisms were integrated into an operation that only requires the organism close to MS inlet that was applied to a high voltage. Living plants and animals were directly induced to generate spray ionization. Direct detection and in vivo monitoring of metabolites and chemical residues in various living organisms were successfully demonstrated. Analysis of a single sample could be completed within 30 s. Overall, contactless ESI-MS provides an attractive in vivo method to straightforward investigation of living organisms.


Assuntos
Muco/química , Praguicidas/análise , Espectrometria de Massas por Ionização por Electrospray/métodos , Animais , Linhagem Celular Tumoral , Crustáceos , Peixes , Metaboloma , Camundongos Endogâmicos BALB C , Neoplasias Experimentais , Plantas/química
6.
Drug Deliv Transl Res ; 11(3): 1133-1143, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-32776211

RESUMO

The platform of the combination chemo-photodynamic therapy has received widespread attention for enhancing anticancer efficacy and inhibiting tumor growth, which supports thermosensitive and controlled drug release. Here, an injectable thermoreversible hydrogel (BPNSs/DTX-M-hydrogel) co-encapsulating black phosphorus nanosheets (BPNSs) and docetaxel (DTX) micelles was prepared to increase drug accumulation in tumor tissue and improve anticancer efficacy. BPNSs were prepared by liquid exfoliation method with a simple and rapid preparation, and DTX micelles were prepared by the thin film dispersion method. Hydrogel was prepared with F127 as hydrogel matrix for intratumoral injection. BPNSs, DTX micelles, and BPNSs/DTX-M-hydrogel were characterized by particle size, morphology, stability and degradation, phase transition feature, and photodynamic performance. And the in vivo anticancer efficacy was evaluated in 4T1 tumor-bearing Balb/c mice. The results showed that the particle size of DTX micelles and BPNSs were about 16 and 180 nm, respectively. The hydrogel with the transformation temperature at near body exhibited great photodynamic efficacy and good biodegradability. Moreover, BPNSs/DTX-M-hydrogel with the combination of chemotherapy and photodynamic therapy exhibited unique anticancer efficacy with low toxicity. In conclusion, the combination platform of chemo-photodynamic therapy based on BPNSs could be a prospective strategy in antitumor research. Graphical abstract.


Assuntos
Antineoplásicos , Fotoquimioterapia , Animais , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Docetaxel/farmacologia , Portadores de Fármacos , Hidrogéis , Camundongos , Micelas , Fósforo/farmacologia , Estudos Prospectivos
7.
Phytochem Anal ; 31(6): 739-746, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32304155

RESUMO

INTRODUCTION: Vinca alkaloids are important sources for producing anticancer drugs from Catharanthus roseus. The phosphorus of soil is one of crucial factors for planting C. roseus. OBJECTIVES: We aim to develop an in vivo sampling technique coupled with direct mass spectrometry with wooden tip for investigating distributions and changes of alkaloids in flowers, leaves, stems, veins and roots of living C. roseus under low-phosphorus stress. MATERIALS AND METHODS: Living C. roseus were prepared under low-phosphorus stress (n = 10) and control conditions (n = 10). Wooden-tip electrospray ionisation mass spectrometry and conventional liquid chromatography-mass spectrometry were applied to analyse living C. roseus and extracts of C. roseus, respectively. RESULTS: Distributions and changes of serpentine, vindoline, catharanthine, and anhydrovinblastine in living C. roseus under low-phosphorus stress and control conditions were successfully obtained. CONCLUSION: Compared to control soil conditions, low-phosphorus soil was found to induce C. roseus to generate more serpentine but less catharanthine and vindoline in leaves, veins, stems and roots, and to generate more anhydrovinblastine in flowers, leaves, stems and roots. Overall, our results showed a simple, rapid, and effective method for in vivo sampling and direct analysis of living plants.


Assuntos
Catharanthus , Cromatografia Líquida de Alta Pressão , Fósforo , Folhas de Planta , Espectrometria de Massas por Ionização por Electrospray
8.
Anal Chem ; 92(9): 6207-6212, 2020 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-32250596

RESUMO

Rapid and sensitive detection of metabolites and chemical residues in human tears is highly beneficial for understanding eye health. In this study, Schirmer paper was used for noninvasive microsampling of human tears, and then paper spray mass spectrometry (PSMS) was performed for direct analysis of human tears. Schirmer PSMS was successfully used for rapid diagnosis of dry-eye syndrome by detecting the volume and metabolites of human tears. Drugs of abuse, therapeutic drugs, and pharmacodynamics in human tears were also investigated by Schirmer PSMS. Furthermore, specific markers of environmental exposures in the air to human eyes, including volatile organic compounds, aerosol, and smoke, were unambiguously sampled and detected in human tears using Schirmer PSMS. Excellent analytical performances were achieved, including single-use, low-sample consumption (1.0 µL), rapid analysis (the whole analytical procedure completed within 3 min), high sensitivity (absolute limit of detection less than or equal to 0.5 pg, signal-to-noise ratio greater than or equal to 3), good reproducibility (relative standard deviation less than 10%, n = 3), and accurate quantitation (average deviation less than 3%, n = 3). Overall, our results showed that Schirmer PSMS is a highly effective method for direct tear analysis and is expected to be a convenient tool for human tear analysis in significant clinical applications.


Assuntos
Espectrometria de Massas/métodos , Papel , Lágrimas/química , Antibacterianos/análise , Síndromes do Olho Seco/diagnóstico , Humanos , Limite de Detecção , Metaboloma , Soluções Oftálmicas/química , Sistemas Automatizados de Assistência Junto ao Leito , Análise de Componente Principal , Reprodutibilidade dos Testes , Razão Sinal-Ruído , Manejo de Espécimes/métodos , Compostos Orgânicos Voláteis/análise
9.
Inorg Chem ; 59(6): 3542-3545, 2020 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-32096409

RESUMO

Stimulated Raman scattering processes based on Raman crystals offer a simple and effective method to generate mid-IR lasers. However, currently available mid-IR Raman crystals are extremely scarce. Herein, a new type of mid-IR Raman crystal, BaGeO3, is reported. It crystallizes in the monoclinic space group C2/c with Ba2+ cations and [Ge3O9]6- rings as basic building units and features high transparency from 2.5 to 5.5 µm and a Raman response larger than that of diamond. The BaGeO3 crystal has 45 IR-active modes (22Au + 23Bu) and 42 Raman-active modes (20Ag + 22Bg). The wide mid-IR transparent window is attributed to the low phonon energy of the second-order IR-active Au ⊗ Bg mode. The strongest Raman band, located at 799 cm-1, arises from the symmetrically stretching vibration of the [Ge3O9]6- extra-ring Ge-O bonds. The findings provide new insights into the crystallographic and Raman spectroscopic characteristics of high-performance mid-IR Raman crystals.

10.
Anal Sci ; 36(3): 341-346, 2020 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-31656247

RESUMO

Direct characterization of native protein binding to ligands in raw biological samples is a challenging task, because the ligand solution might induce proteins to aggregation, flocculation and denaturation. In this work, we developed a reactive wooden-tip electrospray ionization mass spectrometry (ESI-MS) for formation and characterization of protein-ligand complexes upon rapid mixing in electrospray droplets. Raw viscous hen egg white (HEW) was directly loaded onto a wooden tip to induce spray ionization, and sodium dodecyl sulfonate (SDS) solution was directly loaded into the HEW spray by a pipette tip, and thus lysozyme-DS complexes were then formed in the electrospray droplets and were detected subsequently by mass spectrometry. The new approach was successfully applied to investigate interaction of SDS and native lysozyme in electrospray droplets of standard solution and raw egg white. Our results showed that wooden-tip ESI-MS is a promising method to form and characterize protein-ligand complexes.


Assuntos
Clara de Ovo/química , Muramidase/análise , Espectrometria de Massas por Ionização por Electrospray/métodos
11.
Rapid Commun Mass Spectrom ; 33(24): 1877-1883, 2019 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-31429145

RESUMO

RATIONALE: Herbal dietary supplements (HDSs) adulterated with undeclared synthetic drugs can lead to serious health problems METHODS: A fast-switching positive/negative high-voltage (+/- HV) was developed to apply on electrospray ionization mass spectrometry (ESI-MS) with porous tips for rapid screening of five antirheumatic drugs in antirheumatic HDSs. The fast-switching (switch-time: 100 ms) negative and positive ions were alternately generated to perform full-MS and tandem-MS analysis, providing an effective method for rapid detection of analytes in whichever mode of detection was most suitable (negative or positive ion mode). The use of different tips and solvents was also optimized in this work. RESULTS: The limits of detection of the five antirheumatic drugs were found to be less than 0.1 ng/g (S/N > 3). The reproducibility of the five drugs was measured to be 10.0-23.3% (n = 5). A single sample analysis could be completed within 1 min. Rapid screening of a total of 28 real HDS samples collected from the market was examined by the fast-switching HV substrate-tip ESI-MS method, and the screening result was further validated by conventional liquid chromatography/mass spectrometry. CONCLUSIONS: Overall, our results demonstrated that fast-switching HV substrate-tip ESI-MS is a rapid, reliable, and effective method for simultaneous screening of various analytes in complex samples.


Assuntos
Antirreumáticos/análise , Contaminação de Medicamentos , Medicamentos de Ervas Chinesas/análise , Espectrometria de Massas por Ionização por Electrospray/métodos , Suplementos Nutricionais/análise , Contaminação de Medicamentos/estatística & dados numéricos , Sensibilidade e Especificidade
12.
J Mass Spectrom ; 54(9): 772-779, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31426121

RESUMO

In this work, a vibrating tip spray ionization source was developed for direct mass spectrometric analysis of raw samples under voltage-free condition. A solid tip was mounted on a vibrator, and the solid tip was placed on the front of MS inlet. Liquid, viscous, and bulk solid samples could be directly loaded on the tip-end surface, and then a drop of solvent at microliter level was subsequently loaded on the tip for dissolution and extraction of analytes, and a vibrator was then started to atomize and ionize the analytes under ambient condition. We demonstrated vibrating tip spray mass spectrometry in various applications, including food safety, pharmaceutical analysis, and forensic science. Furthermore, in situ analysis of biological tissues and in vivo analysis of living plants were conveniently performed, due to voltage-free. Different vibration frequencies and solvent compositions were investigated. The analytical performances, including sensitivity, reproducibility, and linear range, were investigated. The ionization process and mechanism were also discussed in this work.

13.
Talanta ; 203: 140-146, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31202318

RESUMO

Ambient ionization mass spectrometry is a powerful analytical method for direct analysis of raw samples. Desorption electrospray ionization (DESI) and direct analysis in real time (DART) are two pioneer ambient ionization techniques and have been widely used in various fields. Despite it is a fact that the application and development of DESI and DART are gaining significant attention in analytical science, few comprehensive comparisons of DESI and DART have been made for in-depth understanding their characteristics for direct sample analysis. In this work, substituent effect on DESI and DART were systematically investigated using a serial of model molecules (i.e., tripeptides and fatty acids) that containing same molecular skeleton and different substituents, revealing that DESI response was determined by substituent hydrophilic effect and DART response of analyte was determined by substituent steric effect. Furthermore, matrix effects on DESI and DART were compared by detecting same analyte in different matrices, revealing respective characteristics of DESI and DART for direct sample analysis. Moreover, DESI and DART also were further compared for detecting same samples, including thermostable, thermally unstable, small and larger molecules, demonstrating complementation of DESI and DART to obtain comprehensive information of raw samples for different purposes in real-world applications. Overall, our results provided new insights into the mechanisms and applications of ambient MS with DESI and DART.

14.
J Agric Food Chem ; 67(8): 2265-2271, 2019 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-30735376

RESUMO

Citrus greening disease [Huanglongbing (HLB)] is the most destructive disease of citrus. In this work, we have established a metabolite-based mass spectrometry (MS) method for rapid detection of HLB in navel orange trees. Without sample pretreatment, characteristic mass spectra can be directly obtained from the raw plant samples using the direct MS method. The whole detection process can be accomplished within 1 min. By monitoring and comparisons of the healthy and infected plants throughout a whole year, characteristic MS peaks of metabolites are found to be specific responses from infected plants and, thus, could be used as biomarkers for detection of HLB. Therefore, HLB could be directly detected in the asymptomatic samples, such as stems, using this metabolite-based direct MS method. In addition, principal component analysis and partial least squares discriminant analysis modes of metabolites from healthy and infected trees were established for investigating differentiation and seasonal variations of HLB in leaves, veins, and stems, providing valuable information for understanding the HLB in different seasons.


Assuntos
Citrus sinensis/química , Espectrometria de Massas/métodos , Doenças das Plantas/microbiologia , Citrus sinensis/microbiologia , Metabolômica , Análise de Componente Principal , Rhizobiaceae/fisiologia , Estações do Ano , Árvores/química , Árvores/microbiologia
15.
Anal Chim Acta ; 1050: 105-112, 2019 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-30661577

RESUMO

Electrospray ionization mass spectrometry (ESI-MS) is one of the most powerful ionization techniques for characterization of analytes in various areas. Polar solvents such as methanol, water and acetonitrile are commonly used for ESI-MS analysis, while nonpolar solvents such as hexane were usually considered as non-ESI-friendly solvents. Following our recent work on observation of ESI process from solid substrates using nonpolar solvents (Anal Chim Acta, 2018, 1004, 51-57), the analytical properties of ESI-MS with solid substrates and nonpolar solvents were further systematically investigated in this study. Compared to the uses of polar solvents, our results revealed that nonpolar solvents could serve as extractants for enhanced detection of low-polar analytes from complex samples, and could serve as refrigerants for rapid freezing of samples such as peptides, proteins and protein-ligand complexes. Furthermore, nonpolar solvents could be used for formation of ammonia-transition-metal acetylacetonates complexes under ambient conditions.


Assuntos
Compostos Organometálicos/síntese química , Peptídeos/análise , Proteínas/análise , Solventes/química , Amônia/química , Hidroxibutiratos/química , Ligantes , Metais Pesados/química , Estrutura Molecular , Compostos Organometálicos/química , Pentanonas/química , Espectrometria de Massas por Ionização por Electrospray
16.
J Dermatolog Treat ; 30(6): 605-611, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30388912

RESUMO

Objective: Oral lichen planus (OLP) is a relatively common immunological mucocutaneous disease that causes pain and poor quality of life. Curcumin has been reported to be a safe and effective treatment for OLP. The objective of this review is to evaluate the existing evidence for the safety of curcumin in treating OLP as well as its efficacy compared with that of corticosteroids. Methods: We reviewed the published literature by searching PubMed, EMBASE, EBSCO, and Cochrane Library, and then retrieved and analyzed several variables from patient records. Results: Nine studies met the inclusion criteria, including six randomized, double-blind clinical trials; two pilot clinical trials; and one case report. A total of 259 OLP patients were included in the systematic review. Seven studies showed statistically significant differences in pain severity and clinical appearance of oral lesions after treatment with curcumin for a period of time, compared to baseline (p < .05). Three controlled clinical trials compared the efficacy of curcumin to that of corticosteroids; all of these trials showed no statistically significant differences in pain severity and clinical appearance of oral lesions. Conclusions: Curcumin is a safe treatment and can be used as an adjunct in combination with corticosteroids to reduce pain, burning sensations, and the clinical appearance of oral lesions in OLP patients.


Assuntos
Curcumina/uso terapêutico , Líquen Plano Bucal/tratamento farmacológico , Corticosteroides/uso terapêutico , Ensaios Clínicos como Assunto , Curcumina/efeitos adversos , Bases de Dados Factuais , Gastroenteropatias/etiologia , Humanos , Qualidade de Vida , Resultado do Tratamento
17.
J Mass Spectrom ; 53(12): 1222-1229, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30300951

RESUMO

Conventional electrospray ionization mass spectrometry (ESI-MS) commonly uses capillary tip for sample introduction and ionization. In recent years, ESI-MS using noncapillary substrate tips has attracted growing interest as it allows separation and enrichment of analytes from complex samples due to analytes-substrate interactions. In this work, model mixtures and functionalized tips were employed to investigate the molecular mechanism of the analyte-substrate interactions. The mixtures were directly loaded on substrate tips, and then temporal responses of analytes were investigated by monitoring selected ion chromatogram (SIC) responses of each analyte. It is found that all analytes are sprayed out together when bulk solution loaded substrate surface and then sequential ionization of analytes were observed. Sequential ionization of analytes was affected by the analytes-substrate interactions which caused analytes of weaker-interaction to be faster moved and the analytes of stronger-interactions to be retained on the substrate. The main molecular mechanisms of analyte-substrate interactions were revealed to be hydrophobic interactions and electrostatic interactions. Furthermore, based on the mechanistic insights, functionalized tips were further applied for rapid extractive sampling of target analytes from complex samples with good analytical performances. Overall, this study on the mechanism and applications of analyte-substrate interactions is useful for understanding the fundamental principles and further developments of functionalized tip electrospray ionization (TESI).

18.
Sci Rep ; 8(1): 9903, 2018 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-29967390

RESUMO

Human CD4+ T cells play an important role in the immune response to Mycobacterium tuberculosis (MTB). However, little is known about the spectratyping characteristics of the CD4+ T-cell receptor (TCR) α- and ß-chains CDR3 region in tuberculosis (TB) patients. We sorted MTB peptide E7-bound CD4+ T cells by using E7/HLA-DR tetramers constructed with different HLA-DRB1 alleles and extracted the CDR3 amino-acid sequences of TCR α- and ß-chains. The results showed that the CDR3 sequences of E7-bound CD4+ T cells were completely or partially identical in a single patient. The sequences of MTB peptide C5-bound CD4+ T cells shared another, and non-peptide bound CD4+ T cells, as well as unbound CD4+ T cells with tetramers were different from each other. Specifically, diverse CDR3 sequences of E7-bound CD4+ T cells displayed similar protein tertiary structure in one TB patient. In summary, the TCR α- and ß-chains of CDR3 lineage of CD4+ T cells in TB patients apparently drifted, and the predominant CDR3 sequences of TCR α- and ß-chains that recognized the MTB antigen exhibited peptide specificity, and certain HLA-DR restriction was also established. This study elucidates the possible causes and mechanisms of peptide-specific CD4+ T-cell-related presentation against MTB.


Assuntos
Antígenos de Bactérias/metabolismo , Linfócitos T CD4-Positivos/imunologia , Regiões Determinantes de Complementaridade , Cadeias HLA-DRB1/metabolismo , Mycobacterium tuberculosis , Alelos , Antígenos de Bactérias/química , Antígenos de Bactérias/imunologia , Complexo CD3/metabolismo , Cadeias HLA-DRB1/química , Cadeias HLA-DRB1/imunologia , Humanos , Chaperonas Moleculares/metabolismo , Mycobacterium tuberculosis/imunologia , Receptores de Antígenos de Linfócitos T alfa-beta/imunologia , Receptores de Antígenos de Linfócitos T alfa-beta/metabolismo , Tuberculose/imunologia , Tuberculose/patologia
19.
Chem Commun (Camb) ; 54(39): 4979-4982, 2018 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-29707718

RESUMO

Many nonprecious metal-selenide-based materials have been reported as electrocatalysts with high activity for the oxygen evolution reaction (OER). Herein, a hybrid catalyst film composed of Cu2Se and Cu2O nanoparticles directly grown on Ti foil (Cu2Se-Cu2O/TF) was prepared through a simple and fast cathodic electrodeposition method. Surprisingly, this electrode required a relatively low overpotential of 465 mV to achieve a catalytic current density of 10 mA cm-2 for the OER in 0.2 M carbonate buffer (pH = 11.0). Furthermore, a long-term constant current electrolysis test confirmed the high durability of the Cu2Se-Cu2O/TF anode at a current density of 10 mA cm-2 over 20 h. The XRD, TEM and XPS analysis of the sample after the OER indicated that a CuO protective layer formed on the surface of the Cu2Se-Cu2O catalyst, which effectively suppressed further oxidation of the Cu2Se-Cu2O catalyst during the OER and resulted in sustained catalytic oxidation of water.

20.
Shanghai Kou Qiang Yi Xue ; 27(6): 617-623, 2018 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-30899943

RESUMO

PURPOSE: The aim of this study was to investigate the severity and status of oral mucosa and periodontal status in early and late stage after receiving hematopoietic stem cell transplantation(HSCT). METHODS: This study enrolled patients submitted to hematopoietic stem cell transplantation. Through a survey questionnaire, clinical examination, we collected clinical data from 108 HSCT recipients and divided them into 2 groups: transplantation time less than 1 year and more than 1 year. The oral mucosal and periodontal status were recorded and statistically analyzed with SPSS 21.0 software package. RESULTS: The incidence of oral features after HSCT was 78.95%. The incidence of mild symptoms with HSCT less than 1year (n=32) and HSCT more than 1 year (n=43) was 59.38% and 18.60%, respectively. There was significant difference between the two groups (P=0.001).The percent of lichenoid/hyperkeratotic plaques was 31.25% and 60.47%, respectively. The lichenoid/hyperkeratotic plaques were significantly different between the two groups (P=0.012). The detection rate of shallow and moderate pockets was 49.38% and 40.74%, respectively. Visual plaque, calculus and bleeding on probing were 62.96%, 64.20% and 50.62%, respectively. CONCLUSIONS: The incidence of periodontal and mucosal lesions after HSCT is high. The mild symptoms of oral graft versus host disease in early stage are identified obviously, mainly like lichenoid/hyperkeratotic plaques in late stage.


Assuntos
Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Mucosa Bucal , Humanos , Incidência , Mucosa Bucal/patologia , Transplante Homólogo
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