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1.
Anal Methods ; 2024 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-39329180

RESUMO

Chemical hair dye components can have allergenic, reproductive, and carcinogenic risks. Detecting restricted and prohibited ingredients in these products is challenging due to product diversity, isomer separation, instability, and wide polarity range. A method was developed using HPLC-high-resolution mass spectrometry for the qualitative and quantitative analysis of 54 hair dye components in various products. Samples were extracted with a 70% methanol solution, ultrasonicated in an ice bath, centrifuged, filtered, diluted with 25% methanol solution and 25% methanol solution containing 0.05% D-isoascorbic acid. Separation was achieved using an ACE Excel 3 C18 column (2.1 mm × 150 mm, 3 µm) with analysis conducted via quadrupole Orbitrap mass spectrometry. It showed good linear correlations, with detection limits of 0.1-23.5 ng mL-1, and quantitation limits of 0.2-78.1 ng mL-1. Average recovery ranged from 60.0% to 118.4%, with repeatability from 4.0% to 14.9%. Stability was confirmed within 48 hours. When applied to 20 batches of commercially available hair dyes, 24 hair dye components were found within permissible levels. The method is crucial for quality control of hair dyes, covering 10 common prohibited and 44 permissible hair dye components outlined in the Safety and Technical Standards for Cosmetics (2015 Edition). Compared to the standard methods, it can separate isomers in a single mobile phase system within 15 minutes in positive ion mode while maintaining sensitivity for phenol, hydroquinone, and other components in negative ion mode. Moreover, the pre-treatment strategy significantly improved stability and accuracy, enabling precise analysis of the 54 hair dye components.

2.
Am J Med Sci ; 360(1): 55-63, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32439152

RESUMO

BACKGROUND: Cystic fibrosis transmembrane conductance regulator IVS8-5T gene variation appears to be associated with a higher risk of chronic pancreatitis (CP); however, there is inconsistency between previous reported studies. Here, we performed a meta-analysis to investigate this relationship. MATERIALS AND METHODS: PubMed and WANFANG databases were searched for the case-control studies that contained Patients with CP with IVS8-5T variation. Odd ratios (ORs) and 95% confidence intervals (CIs) were calculated to assess the relevance of IVS8-5T gene variation and CP. RESULTS: Analysis showed that the frequency of the 5T allele was significantly higher in CP subjects than that in control subjects (OR = 1.43, 95% CI: 1.13-1.81, I2 = 1.2%). Based on the subgroup analysis stratified by etiology, the 5T allele was associated with a higher risk of idiopathic chronic pancreatitis (ICP) (OR = 1.80, 95% CI: 1.18-2.76, I2 = 0.0%) and not alcoholic CP (OR = 2.14, 95% CI: 0.98-4.66, I2 = 0.0%). Further study indicated that the 5T allele was related to higher ICP prevalence in the European population (OR = 1.79, 95% CI: 1.06-3.03, I2 = 0.0%). In contrast, there was no significant difference between ICP subjects and healthy controls within the Asian population (OR = 1.84, 95% CI: 0.91-3.72, I2 = 38.0%). CONCLUSIONS: Cystic fibrosis transmembrane conductance regulator IVS8-5T is a risk factor in patients with CP. IVS8-5T variation may play a significant role in the occurrence of ICP, especially in the European population.


Assuntos
Regulador de Condutância Transmembrana em Fibrose Cística/genética , Predisposição Genética para Doença , Pancreatite Crônica/genética , Alelos , Variação Genética , Humanos , Razão de Chances , Fatores de Risco
3.
Cancer Manag Res ; 11: 2073-2085, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30881131

RESUMO

BACKGROUND: Previous accidental findings showed that administration of immunoglobulin G (IgG) in treating autoimmune diseases was able to inhibit cancers that happened to grow in these patients. However, such treatment has not been used to treat cancer patients clinically. The mechanism and optimal dosages of this treatment have not been established. Subsequent animal experiments confirmed this effect, but all previous studies in animal models used human IgG which was heterogeneous to the animal hosts and therefore could adversely interfere with the results. MATERIALS AND METHODS: We tested different dosages of mouse IgG in treating and preventing three syngeneic cancer types (melanoma, colon cancer, and breast cancer) in three immune potent mouse models. The expression of Ki67, CD34, VEGF, MMPs, and cytokines in tumor tissues were examined with immunohistochemistry or quantitative real-time PCR to evaluate tumor proliferation, vascularization, metastasis, and proinflammatory response in the tumor microenvironment. RESULTS: We found that low-dose IgG could effectively inhibit cancer progression, regulate tumor vessel normalization, and prolong survival. Administration of IgG before cancer cell inoculation could also prevent the development of cancer. In addition, IgG caused changes in a number of cytokines and skewed macrophage polarization toward M1-like phenotype, characterized by proinflammatory activity and inhibition of proliferation of cancer cells. CONCLUSION: Our findings suggest that nonspecific IgG at low dosages could be a promising candidate for cancer prevention and treatment.

4.
Oncotarget ; 7(21): 31166-76, 2016 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-27145274

RESUMO

Concanavalin A (ConA) chromatography has been extensively used to separate asymmetric Immunoglobulin G (IgG), which possesses oligosaccharide attached to one of the two F(ab')2 arms, from symmetric IgG with no glycan attached to Fab fragments. In this study, applying affinity chromatography, silver stain, Western blot and lectin stain techniques, N- linked oligosaccharide attached to Fab fragment was demonstrated to be exposed on the surface of the protein and be accessible by ConA. In contrast, N- linked oligosaccharide attached to asparagine (Asn) 297 of IgG Fc was located in the inside of the natural protein and was inaccessible by ConA. In addition to asymmetric IgG, there are also detectable level of IgG with both F(ab')2 arms glycosylated that has not been reported previously. The discoveries of new basic molecular structure of IgG would have implications in understanding the function and properties of this important immune molecule with clinical applications.


Assuntos
Concanavalina A/química , Fragmentos Fab das Imunoglobulinas/química , Imunoglobulina G/química , Fracionamento Químico , Cromatografia/métodos , Glicosilação , Humanos , Imunoglobulina G/sangue , Imunoglobulina G/isolamento & purificação
5.
Oncotarget ; 7(13): 15606-17, 2016 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-26870994

RESUMO

Influenza viruses possess a great threat to human health, but there is still no effective drug to deal with the outbreak of possible new influenza subtypes. In this study, we first fractionated sialylated immunoglobulin G (IgG), mainly Fab sialylated fraction, with sambucus nigra agglutinin affinity chromatography. We then demonstrated that sialylated IgG possessed more effective neutralizing activity against 2009 A (H1N1) subtype than that of IgG mixture, and sialosides on the Fab is crucial in this neutralization reaction as when such residues were removed with neuraminidase A digestion the blocking effect was significantly reduced. It appears that sialic acid residues attached to Fab could serve as binding moieties to receptor binding site of influenza virus. These findings indicate that sialylated IgG probably is an effective anti-influenza broad-spectrum drug utilizing its receptor mimicry to competitively inhibit the attachment of influenza viruses with sialic acid receptors on target cells. This property would be particularly useful if it can be applied to prevent newly emerged influenza virus strain infections in future epidemics.


Assuntos
Fragmentos Fab das Imunoglobulinas/imunologia , Imunoglobulinas Intravenosas/imunologia , Influenza Humana/imunologia , Mimetismo Molecular/imunologia , Receptores de Superfície Celular/imunologia , Anticorpos Neutralizantes/química , Anticorpos Neutralizantes/imunologia , Humanos , Fragmentos Fab das Imunoglobulinas/química , Imunoglobulinas Intravenosas/química , Vírus da Influenza A Subtipo H1N1/imunologia , Vacinas contra Influenza/imunologia , Ácido N-Acetilneuramínico
6.
Virus Genes ; 47(1): 34-41, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23546824

RESUMO

No effective vaccine has been developed against the subgroup J avian leukosis virus (ALV-J). The genetic diversity of ALV-J might be related to the env gene, therefore, we selected conserved sequences of the env gene and designed interference sequence. In this study, microRNAs (miRNAs) were designed and synthesized, corresponding to conserved regions of the env gene. These miRNAs were cloned into the linearized eukaryotic expression vector. The recombinant plasmids were transfected into DF-1 cells. After transfection, the cells were inoculated with ALV-J. In reporter assays, the transfection efficiency is 80% by indirect immunofluorescence (IFA). Expression of the virus envelope glycoprotein was measured by IFA and western blotting assays. The relative expression of env gene was determined using quantitative PCR. Our results show that the mi-env 231 and mi-env 1384 could effectively suppress the replication of ALV-J with an efficiency of 68.7-75.2%. These data suggest that the miRNAs targeting the env can inhibit replication of ALV-J efficiently. This finding provides evidence that miRNAs could be used as a potential tool against ALV infection.


Assuntos
Vírus da Leucose Aviária/genética , Leucose Aviária/virologia , MicroRNAs/genética , Doenças das Aves Domésticas/virologia , RNA Viral/genética , Proteínas do Envelope Viral/genética , Replicação Viral , Animais , Leucose Aviária/terapia , Vírus da Leucose Aviária/fisiologia , Linhagem Celular , Galinhas , Terapia Genética/veterinária , MicroRNAs/metabolismo , Doenças das Aves Domésticas/terapia , Proteínas do Envelope Viral/metabolismo
7.
J Chromatogr A ; 1272: 73-80, 2013 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-23261069

RESUMO

A quantitative characterization of Polysorbate 80 is crucial for its many applications. In this paper we report a quick RP-HPLC method for the quantitative determination of Polysorbate 80. The hydrolysis of Polysorbate 80 to release oleic acid and three types of polyethers was first carried out. A chromatographic method based on liquid chromatography at critical conditions (LCCC) was then developed for an endgroup-based separation of low-molecular-mass polyether. With this method the polyether, irrespective of its molecular-mass, is separated according to endgroups (functionality) due to interactions of the polar endgroups with the hydrophilic stationary phase. The different types of polyethers and oleic acid were identified using on-line electrospray ionization mass spectrometry and quantified by evaporative light scattering detection.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Éteres/análise , Interações Hidrofóbicas e Hidrofílicas , Ácido Oleico/análise , Polissorbatos/química , Adsorção , Calibragem , Radical Hidroxila , Polietilenoglicóis/química , Polissorbatos/síntese química , Padrões de Referência , Reprodutibilidade dos Testes
8.
Virol J ; 8: 556, 2011 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-22188662

RESUMO

BACKGROUND: Avian leukosis virus (ALV) is a major infectious disease that impacts the poultry industry worldwide. Despite intensive efforts, no effective vaccine has been developed against ALV because of mutations that lead to resistant forms. Therefore, there is a dire need to develop antiviral agents for the treatment of ALV infections and RNA interference (RNAi) is considered an effective antiviral strategy. RESULTS: In this study, the avian leukosis virus subgroup J (ALV-J) proviral genome, including the gag genes, were treated as targets for RNAi. Four pairs of miRNA sequences were designed and synthesized that targeted different regions of the gag gene. The screened target (i.e., the gag genes) was shown to effectively suppress the replication of ALV-J by 19.0-77.3%. To avoid the generation of escape variants during virus infection, expression vectors of multi-target miRNAs were constructed using the multi-target serial strategy (against different regions of the gag, pol, and env genes). Multi-target miRNAs were shown to play a synergistic role in the inhibition of ALV-J replication, with an inhibition efficiency of viral replication ranging from 85.0-91.2%. CONCLUSION: The strategy of multi-target miRNAs might be an effective method for inhibiting ALV replication and the acquisition of resistant mutations.


Assuntos
Vírus da Leucose Aviária/efeitos dos fármacos , Vírus da Leucose Aviária/metabolismo , MicroRNAs/farmacologia , Interferência de RNA , Replicação Viral/efeitos dos fármacos , Animais , Leucose Aviária/virologia , Vírus da Leucose Aviária/genética , Vírus da Leucose Aviária/fisiologia , Linhagem Celular , Produtos do Gene env/genética , Produtos do Gene env/metabolismo , Produtos do Gene gag/genética , Produtos do Gene gag/metabolismo , Produtos do Gene pol/genética , Produtos do Gene pol/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Doenças das Aves Domésticas/virologia , Transfecção
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