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1.
Se Pu ; 39(10): 1128-1136, 2021 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-34505435

RESUMO

Exosomes, which are extracellular vesicles with sizes of 30-150 nm, contain proteins, lipids, RNA, etc., which can reflect important information about parental cells. They also have unique structures and can perform characteristic biological functions. Although the release of exosomes is a normal process, tumor cells release more exosomes, and the contents can induce cancer progression. Exosomes are widely distributed in body fluids at high concentrations and are easy to obtain; hence, the collection of exosomes released by tumor cells has become one of the main directions in tumor liquid biopsy. In order to ensure the reproducibility and consistency of liquid biopsy results, it is necessary to develop methods for enriching exosomes in sufficient yield and purity from complex samples. Based on the size, hydrophobic proteins, and characteristic proteins of exosomes, various methods for exosome separation and purification have been developed, such as ultracentrifugation, polymer precipitation, and immunoaffinity methods. An aptamer (Apt) is an oligonucleotide chain with a total length of 20-100 nt, which has ligand binding properties and can be used to detect different types of drugs and biomolecules at the nanomolar level. Characteristic proteins on the surface of exosomes such as CD63, CD9, and CD81 are often used as exosomes markers. At present, a variety of aptamer sequences targeting the characteristic proteins of exosomes have been reported. Zirconium and titanium cations as well as the oxides of these metals show high affinity to the phospholipid bilayer on the exosome surface and are used in the separation and purification of exosomes. Metal organic frameworks (MOFs) can provide a wealth of metal oxide affinity sites to interact with the phospholipid bilayer membrane, and their diverse organic ligands can provide numerous modification sites to bind with aptamers. In this study, different metal/aptamer dual-functional composite magnetic nanomaterials were prepared by exploiting the surface chemistry and biological characteristics of exosomes for the enrichment and purification of exosomes. Because of the specific affinity of the aptamers toward the target membrane protein on the exosome surface and the affinity of the titanium or zirconium oxide toward the phospholipid bilayer membrane of exosomes, dual-functional magnetic nanomaterials can greatly improve the enrichment capacity and separation selectivity of exosomes. Fe3O4@Zr-MOFs was used as the substrate to fabricate the dual functional MOFs/metal oxide aptamer composite magnetic nanomaterial Fe3O4@Zr-MOFs-Apt. UiO-66-NH2 was grown in situ on the surface of Fe3O4 by a solvothermal method to form a Zr-MOFs layer, and aptamer-CD63 was covalently bonded to the amino group of the organic ligand of the MOFs. The magnetic bimetallic metal organic framework Fe3O4@Zr-Ti-MOFs, which was fabricated via a layer-by-layer assembly approach, was used as the substrate to prepare the dual functional MOFs/metal oxide aptamer composite Fe3O4@Zr-Ti-MOFs-Apt via coordination bond formation between the metal site on the Fe3O4@Zr-Ti-MOFs and the aptamers. The third dual functional MOFs/metal oxide aptamer composite magnetic nanomaterial, Fe3O4@TiO2-Apt, was prepared by using Fe3O4@TiO2 as the substrate via coordination bond formation between the metal site on Fe3O4@TiO2 and the aptamers. Considering model exosomes extracted by ultracentrifugation and urine as samples, this paper compared the enrichment performance of materials modified with the same quality of aptamers and different levels of metal oxides. The dual-functional composite magnetic nanomaterials modified with different metals/aptamers were used for the enrichment of urine exosomes. The obtained exosomes were lysed and identified by mass spectrometry, and 233, 343, and 832 exosomal proteins were identified. This result also shows that dual-functional magnetic nanomaterials can fully combine the high selectivity of the nucleic acid aptamer and the high enrichment capacity of the metal oxides. The rapid, efficient separation and purification of exosomes in biological samples has excellent application potential. The material design and purification methods also provide a new idea for the development of new exosome-enrichment materials.


Assuntos
Exossomos , Nanoestruturas , Fenômenos Magnéticos , Oligonucleotídeos , Reprodutibilidade dos Testes
2.
Cleft Palate Craniofac J ; : 10556656211044396, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34524929

RESUMO

To investigate the longitudinal influence of alveolar bone grafting on the oral microbiota of children with cleft lip and palate (CLP).Twenty-eight children with nonsyndromic CLP were recruited and underwent secondary alveolar bone grafting at the first time. Unstimulated saliva and plaque samples were collected from the subjects preoperatively and at 2 days, 1 month, and 3 months postoperatively. The v3-v4 hypervariable regions of the 16S rRNA gene from bacterial DNA were sequenced using the Illumina MiSeq sequencing platform.The alpha diversity of the saliva and plaque microbiota was significantly decreased at 2 days postoperatively and then increased at 1 and 3 months postoperatively. The saliva and plaque microbiota compositions at 2 days postoperatively differed from those at the other time points, and the microbiota compositions at 1 and 3 months postoperatively showed a gradual shift toward the preoperative composition. The saliva, but not plaque, microbiota composition 3 months postoperatively was similar to that preoperatively.The effect of secondary alveolar bone grafting on the plaque microbiota in children with CLP lasted longer than the saliva microbiota. Alveolar bone grafting altered the saliva microbiota in children with CLP within 3 months postoperatively.

3.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 39(4): 369-376, 2021 Aug 01.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-34409791

RESUMO

Malocclusion is one of the three most common oral diseases reported by World Health Organization(WHO). In China, its incidence rate is rising. Malocclusion seriously affects the dental and maxillofacial function, facial appearance and growth development of nearly 260 million children in China, and what is more, it affects their physical and mental health development. Malocclusion occurrence is related to genetic and environmental factors. Early treatment of malocclusion can create a good dental and maxillofacial development environment, correct abnormal growth and control the adverse effects of abnormal genetic factors. It can effectively reduce the prevalence of children's malocclusion and enhance their physical and mental health. This is an urgent need from the economic perspective of our society, so it has great practical and social significance. Experts from the project group "standard diagnose and treatment protocols for early orthodontic intervention of malocclusions of children" which initiated by China National Health Institute of Hospital Administration wrote the "China Experts' Consensus on Preventive and Interceptive Orthodontic Treatments of Malocclusions of Children", which aims to guide and popularize the clinical practice, improve the clinical theory and practice level, and accelerate the disciplinary development of early treatment of children's malocclusion in China. The consensus elaborates the harmfulness of malocclusion and the necessity of early treatment, and brings up the principles and fundamental contents. Based on the law of dental and maxillofacial development, this paper puts forward the guiding suggestions of preventive and interceptive treatments in different stages of dental development ranging from fetus to early permanent dentition. It is a systematic project to promote and standardize the early treatment of malocclusion. Through scientific and comprehensive stratified clinical practice and professional training, the clinical system of early treatment of malocclusion in China will eventually be perfected, so as to comprehensively care for children's dental and maxillofacial health, and improve their oral and physical health in China.


Assuntos
Má Oclusão , Criança , China/epidemiologia , Consenso , Assistência Odontológica , Humanos , Má Oclusão/epidemiologia , Má Oclusão/prevenção & controle , Ortodontia Interceptora
4.
BMC Infect Dis ; 21(1): 632, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34210275

RESUMO

BACKGROUND: Infection with Salmonella enterica usually results in diarrhea, fever, and abdominal cramps, but some people become asymptomatic or chronic carrier as a source of infection for others. This study aimed to analyze the difference in serotype, antimicrobial resistance, and genetic profiles between Salmonella strains isolated from patients and those from asymptomatic people in Nantong city, China. METHODS: A total of 88 Salmonella strains were collected from patients and asymptomatic people from 2017 to 2018. Serotyping, antimicrobial susceptibility testing, and PFGE analysis were performed to analyze the characteristics of these strains. RESULTS: Twenty serotypes belonging to 8 serogroups were identified in the 88 Salmonella strains. S. Typhimurium remained to be the predominant serotype in strains from both patients and asymptomatic people. Among the 27 strains from patients, S. Enteritidis and S. Rissen were shown as the other two major serotypes, while S. London, S. Derby, and S. Meleagridis were demonstrated as the other significant serotypes among the 61 strains from asymptomatic people. Antimicrobial resistance testing revealed that 84.1% of strains from both resources were multi-drug resistant. PFGE displayed a highly discriminative ability to differentiate strains belonging to S. Derby, S. Typhimurium, etc., but could not efficiently differentiate serotypes like S. Enteritidis. CONCLUSIONS: This study's results demonstrated that S. Typhimurium could cause human infection in both symptomatic and asymptomatic state; S. London, S. Derby, and S. Meleagridis usually cause asymptomatic infection, while S. Enteritidis infection mainly results in human diseases. The high multi-drug resistance rate detected in the antimicrobial resistance and diverse PFGE profiles of these strains implied that the strains were isolated from different sources, and the increased surveillance of Salmonella from both patients and asymptomatic people should be taken to control the disease.


Assuntos
Salmonella/classificação , Salmonella/genética , Salmonella/isolamento & purificação , Sorogrupo , Adolescente , Adulto , Idoso , Infecções Assintomáticas/epidemiologia , Criança , Pré-Escolar , China/epidemiologia , Farmacorresistência Bacteriana Múltipla , Eletroforese em Gel de Campo Pulsado , Feminino , Humanos , Lactente , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Infecções por Salmonella/epidemiologia , Sorotipagem
5.
Front Microbiol ; 12: 655500, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34248870

RESUMO

This study aimed to the variations of fungal diversity and community structure in different parts of traditional homemade Sichuan pork bacon. A total of seven phyla and 91 fungal genera were identified. Among them, Ascomycota and Basidiomycota were the first and second most abundant phyla in the bacon tissues. In addition, five dominant genera (Aspergillus, Candida, Debaryomyces, Malassezia, and Penicillium) were shared by all bacon tissues. The numbers of OTUs unique to individual groups were 14, 67, and 65 for the muscle tissue, the adipose tissue, and pork skin, respectively. Linear discriminant analysis showed that a total of 31 taxa significantly differed among the groups. Results of redundancy analysis indicated that fat content, protein content, aw, and pH of bacon tissue shaped the bacon fungal communities. Results of network analysis also indicated that tissue type was a crucial factor influencing the fungal interactions in different tissues. This study can lay a foundation for further isolation and identification of fungi in the product and provides a basis for further research of food health in homemade traditional pork bacon.

7.
J Phys Condens Matter ; 33(35)2021 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-34126611

RESUMO

Layer- and stacking-dependent physical properties discovered in van der Waals materials have attracted a lot of attention recently. In this work, we have investigated the Raman spectrum of layered magnetic CrCl3with different atomic thickness and stacking order from first principles. Our study indicates Raman shift ofR3̄andC2/mphase is near degenerate except that the first and fourth Raman resonant modes exhibit a marked peak difference about 3 cm-1, which can be understood by stacking-dependent vibrational eigenvectors. Moreover, we also find that both frequency and intensity of Raman modes of few-layer CrCl3increase with the number of layers simultaneously. Furthermore, the Raman tensor and polarization-dependent Raman intensity are also evaluated in details, which are found to be in good agreement with available experiments. Our results proposed several distinctive signals to identify layer number and stacking order of layered CrCl3, which will provide an important reference to further experimental study.

8.
Front Oncol ; 11: 630706, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33968730

RESUMO

Clear cell renal cell carcinoma (ccRCC) is the most common type of kidney tumor worldwide. Analysis of The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases showed that the immune-related gene (IRG) hematopoietic cell signal transducer (HCST) could provide guidance for the diagnosis, prognosis, and treatment of ccRCC. The RNA-seq data of ccRCC tissues were extracted from two databases: TCGA (https://www.cancer.gov/about-nci/organization/ccg/research/structural-genomics/tcga) and GEO (https://www.ncbi.nlm.nih.gov/geo/). Corresponding clinical information was downloaded from TCGA. Immune-related gene data were extracted from the IMMPORT website (https://www.immport.org/). Differential analysis with R software (https://www.r-project.org/) was used to obtain a prognosis model of ccRCC IRGs. The differences were combined with the clinical data to assess the usefulness of the HCST as a prognostic biomarker. Based on data obtained from the Oncomine (https://www.oncomine.org/), Human Protein Atlas (https://www.proteinatlas.org/), and PubMed (https://pubmed.ncbi.nlm.nih.gov/) databases, the expression levels of the HCST in ccRCC, clinical-pathological indicators of relevance, and influence on prognosis were analyzed. Regulation of the HCST gene in ccRCC was assessed by gene set enrichment analysis (GSEA). In TCGA/GEO databases, the high HCST expression in tumor tissues was significantly correlated to the TMN stage, tumor grade, invasion depth, and lymphatic metastasis (p < 0.05). The overall survival (OS) of patients with high HCST gene expression was significantly lower than that of patients with low HCST gene expression (p < 0.001). Multivariate Cox regression analysis suggested that the HCST expression level [hazard ratio (HR) = 1.630, 95% confidence interval (CI) = 1.042-2.552], tumor cell grade (HR = 1.829, 95% CI = 1.115-3.001), and distant metastasis (HR = 2.634, 95%, CI = 1.562-4.442) were independent risk factors affecting the OS of ccRCC patients (all, p < 0.05). The GSEA study showed that there was significant enrichment in cell adhesion, tumorigenesis, and immune and inflammatory responses in HCST high expression samples. Hematopoietic cell signal transducer expression was closely associated with the levels of infiltrating immune cells around ccRCC tissues, especially dendritic cells (DCs). In conclusion, the present study suggested that the HCST was interrelated to the clinicopathology and poor prognosis of ccRCC. High HCST expression was also closely correlated with the levels of tumor-infiltrating immune cells, especially DCs.

9.
Anal Chim Acta ; 1158: 338412, 2021 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-33863420

RESUMO

In this work, a dual-functionalized magnetic bimetallic metal-organic framework composite denoted as Fe3O4@SiO2@(Zr-Ti-MOF)10-NH2 was ingeniously designed and fabricated by a facial layer-by-layer assembly technique. The composite not only exhibited strong affinity for phosphopeptide due to the coexistence of Zr-O clusters and Ti-O clusters, but also owned great hydrophilicity for glycopeptides relying on abundant hydrophilic NH2 groups, meeting the demand for simultaneously enrichment and sequential elution of phosphopeptides and glycopeptides. As expected, the synthesized composite showed great selectivity (1:2000 M ratio of ß-casein:BSA; 1:50 M ratio of IgG:BSA), good sensitivity (1 fmol µL-1 for both α-casein and IgG), and good capacity (80 mg g-1 for α-casein and 200 mg g-1 for IgG). By using sequential elution strategy, 29 phosphopeptides and 24 glycopeptides from α-casein and IgG digests mixture could be simultaneously enriched and respectively detected through a single-step enrichment and sequential elution method. Furthermore, the composite was successfully applied to the analysis of intricate biological samples. 4 endogenous phosphopeptides and 20 phosphopeptides were trapped from human serum and non-fat milk tryptic digest respectively. From 0.5 mg of tryptic digest of rat brain, 141 N-linked glycopeptides corresponding to 127 glycoproteins and 918 phosphopeptides corresponding to 397 phosphoproteins were enriched simultaneously and identified respectively, proving the Fe3O4@SiO2@(Zr-Ti-MOF)10-NH2 to be a dependable candidate for the simultaneously enrichment of trace phosphopeptides and glycopeptides in intricate biological samples.


Assuntos
Estruturas Metalorgânicas , Fosfopeptídeos , Glicopeptídeos , Fenômenos Magnéticos , Dióxido de Silício
10.
Anal Chim Acta ; 1161: 338467, 2021 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-33896563

RESUMO

Protein methylation as one of the most important post-translational modifications has been under the spotlight due to its essential role in many biological processes. Development of methods for large-scale analysis of protein methylation greatly accelerates the related researches. To date, antibody-based enrichment strategy is the most common approach for methylproteomics analysis. However, it is still lacking of a pan-specific antibody to enrich peptides or proteins carrying all kinds of lysine and arginine methylation forms. Herein, an online basic strong cation exchange chromatography was developed to enrich methylated peptides from protein digests prepared by two complementary methods, including direct multiple enzymes digestion and carboxylic amidation followed by multiple enzymes digestion. After enrichment, the majority of identifications were obtained from direct multiple enzymes digested sample. The enrichment specificity of methylated peptides was up to 28.5%, and 445 methylation forms corresponding to 376 methylation sites were identified on 194 proteins in one LC-MS/MS run using only 100 µg of digests. This method has great potential in studying protein methylation mediated biological processes.


Assuntos
Peptídeos , Espectrometria de Massas em Tandem , Cátions , Cromatografia Líquida , Lisina/metabolismo , Peptídeos/metabolismo , Processamento de Proteína Pós-Traducional
11.
Nanoscale ; 13(9): 4821-4827, 2021 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-33644793

RESUMO

The newly discovered 2D magnetic materials provide new opportunities for basic physics research and device applications. However, their low Curie temperature (TC) is a common weakness. In this paper, by combining magnetic Hamiltonian, Wannier functions and first-principles calculations, we systematically study the magnetic properties of monolayer CrI3 functionalized with halogens. The magnetic exchange coupling (EX) and magnetic anisotropy (MA) are found to increase significantly with X (X = F, Cl and Br) atom adsorption, and increase with increased coverage of X. In the framework of superexchange theory, the enhanced EX can be ascribed to the reduced energy difference and increased hopping strength between Cr d and I p orbitals, due to the states of the I ligand engineered by the X adatom. Besides, the X adatom may provide an additional ferromagnetic superexchange channel. Our results not only give insight into understanding the enhancement of ferromagnetism of CrI3 by atom adsorption, but also propose a promising way to improve the ferromagnetism of 2D magnetic materials.

12.
Analyst ; 146(7): 2255-2263, 2021 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-33599631

RESUMO

Highly effective enrichment of endogenous phosphopeptides from complex biological samples is an essential and crucial theme in the analysis of phosphopeptidomics. Herein, an ordered mesoporous TiO2/C composite (denoted as Ti-MCM) was prepared by the pyrolysis of MIL-125 under a N2 atmosphere. The obtained Ti-MCM possesses a high specific surface area (165 m2 g-1), a uniform pore size (3.75 nm), and a large amount of Ti (46%). By utilizing the selective chelation between Ti-MCM and phosphopeptides, 25 phosphopeptides were detected in α-casein digest after enrichment. The material shows good selectivity even in the presence of 2000-fold excess of interference peptides. It was also used to enrich endogenous phosphopeptides from the complex samples of human serum and saliva and showed a good performance.


Assuntos
Fosfopeptídeos , Titânio , Caseínas , Humanos , Dietilamida do Ácido Lisérgico/análogos & derivados , Óxidos
13.
Clin Hemorheol Microcirc ; 78(2): 163-174, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33579829

RESUMO

OBJECTIVE: To compare the diagnostic efficacy of ACR TI-RADS, Kwak TI-RADS, ATA guidelines and KTA/KSThR guidelines in combination with shear wave elastography (SWE) for thyroid nodules. METHODS: The retrospective study included 566 thyroid nodules with maximum diameter≥5 mm which confirmed by FNA cytology or/and surgical pathology. The sensitivity, specificity, accuracy, Youden index of diagnosis of thyroid nodules by ACR TI-RADS, Kwak TI-RADS, ATA guidelines, KTA/KSThR guidelines and SWE were calculated. The ROC curve was drawn to determine the cut-off values of the four ultrasound classification systems and SWE Emax. The diagnostic efficacy of the four ultrasound classification systems in combination with SWE were calculated and compared with those of pre-combination. RESULTS: The ROC curves indicated that the cut-off value of ACR TI-RADS, Kwak TI-RADS, ATA guidelines, KTA/KSThR guidelines and Emax of SWE was TR5, 4c, high-suspicion, high-suspicion, and 41.7 kPa, respectively, and the area under the ROC curve (AUC) was 0.907(0.879-0.934), 0904(0.876-0.932), 0.894(0.863-0.924), 0.888(0.856-0.919), 0.886(0.859-0.913), respectively. After combination with SWE, the the sensitivities of the four ultrasound classification systems for the diagnosis of nodules were improved, and the differences were statistically significant (all P≤0.001); the specificities were decreased, but the differences were not statistically significant (all P > 0.05); the accuracies were improved, but only the difference of ACR TI-RADS was statistically significant (x2 = 4.45, P = 0.035); the differences in the AUCs were not significant (all P > 0.05). CONCLUSIONS: The four ultrasound classification systems and SWE all had high performance in the diagnosis of thyroid nodules. The four classification systems in combination with SWE were all beneficial to the differential diagnosis of nodules, and ACR TI-RADS in combination with SWE was more effective, especially for TR3 and TR4 nodules.


Assuntos
Técnicas de Imagem por Elasticidade/métodos , Guias de Prática Clínica como Assunto/normas , Nódulo da Glândula Tireoide/diagnóstico , Ultrassonografia/métodos , Adulto , Área Sob a Curva , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Nódulo da Glândula Tireoide/classificação , Nódulo da Glândula Tireoide/diagnóstico por imagem
14.
Spectrochim Acta A Mol Biomol Spectrosc ; 248: 119287, 2021 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-33316654

RESUMO

The complex 4f and 5d orbits of lanthanide oxide clusters increases the complexity and difficulty in both theoretical and experimental research. Combining the photoelectron imaging spectroscopy and ab initio calculations, the structural and electronic properties of HoO- were studied. The adiabatic detachment energy (ADE) and vertical detachment energy (VDE) of HoO- have been measured to be 1.31(3) eV and 1.42(2) eV, respectively. To determine the vibrational structure and observed spectral bands in the photoelectron spectrum, Franck-Condon simulation of the ground-state transition for HoO- has been performed. The fundamental frequency of ground-state HoO is estimated to be 893 ± 73 cm-1. Density functional method (DFT) was used to study the neutral and anionic clusters of HoOn-1/0 (n = 1-3), and the most stable cluster structures were obtained. Based on the DFT calculations, the theoretical ADEs and VDEs of anionic HoOn- (n = 1-3) clusters were obtained and the photoelectron spectra (PES) of HoOn- (n = 1-3) clusters were simulated, which might stimulate further experimental investigations on the Ho oxide clusters. In addition, the corresponding molecular orbitals (MOs) were also discussed to reveal the interaction between Ho and O atoms. This study can help us to understand the chemical bonding in Ho-containing molecules and will provide some light in their surface chemistry and photochemistry investigation.

15.
Talanta ; 224: 121765, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33379007

RESUMO

In this study, a new molecularly imprinted material, MIP@UiO-66-NH2, was synthesized with glutathione (GSH) as template and mesoporous metal organic framework (UiO-66-NH2) as matrix. The molecularly imprinted polymer was modified on the surface and into the pores of the UiO-66-NH2 by surface molecular imprinting method with thin polymer layer. Based on high specific surface area (1091.93 m2 g-1) and appropriate pore size (35 nm) of the ordered mesoporous UiO-66-NH2, the adsorption capacity for GSH reached 94.43 mg g-1, and the adsorption equilibrium could be achieved within 30 min. The adsorption isotherm data of MIP@UiO-66-NH2 could be described well by Freundlich model and the kinetic data complied well with pseudo-second-order model. In addition, the MIP@UiO-66-NH2 showed low adsorption capacity to GSH structural analogs (QL-cys = 6.51 mg g-1), suggesting great selectivity for GSH recognition. Finally, the MIP@UiO-66-NH2 was successfully applied for selective separation of GSH from BSA, skim milk and egg white tryptic digest.


Assuntos
Estruturas Metalorgânicas , Impressão Molecular , Adsorção , Peptídeos , Polímeros
16.
Anal Chim Acta ; 1142: 48-55, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33280703

RESUMO

A challenge for shotgun proteomics is the identification of low abundance proteins, which is always hampered owing to the extreme complexity of protein digests and highly dynamic concentration range of proteins. To reduce the complexity of the peptide mixture, we developed a novel method to selectively enrich N-terminal proline peptides via hydrazide chemistry. This method consisted of ortho-phthalaldehyde (OPA) blocking of primary amines in peptides, reductive glutaraldehydation of N-terminal proline and solid phase hydrazide chemistry enrichment of aldehyde-modified N-terminal proline peptide. After enrichment, the number of detected peptides containing N-terminal proline increased from 1304 to 4039 and the ratio of N-terminal proline peptides jumped from 4.4% to 93.7%, showing good enrichment specificity towards N-terminal proline peptides. Besides, the ratio of identified peptides to proteins was decreased from 7.8 (29751/3811) to 1.5 (4347/2821), indicating that sample complexity was drastically reduced through this method. As a result, this novel approach for enriching N-terminal proline peptides is effective in identification of low abundance protein owing to the reduction of sample complexity.


Assuntos
Prolina , Proteômica , Aminas , Peptídeos , Proteínas
17.
Talanta ; 221: 121612, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33076142

RESUMO

The composite materials consist of Covalent Organic Frameworks (COFs) and silica have been regarded as a kind of promising stationary phases due to combination of the large specific surface area and good mechanical strength of porous silica microspheres and the porous structure and the excellent stability of COFs. Herein, a novel COFs-silica composite (SiO2@rLZU1, reduced Lan Zhou University-1) was prepared via an in-situ growth strategy with a 32 nm-thick COFs layer on the surface of silica and a 2.2 nm-thick COFs layer on the inner surface of the mesopores of spherical silica (5 µm, 120 Å). With secondary amine and phenyl groups, the novel stationary phase provided hydrophilic, hydrophobic and π-π interactions when used in HPLC, showing different selectivity from typical reversed-phase stationary phases. Probe molecules with aromatic moieties varying in polarity, including acidic (phenol, pyrocatechol, and pyrogallol), basic (aniline, 4-chloroaniline, and 4-nitroaniline) and neutral (benzene homologues) compounds, were all baseline separated on the SiO2@rLZU1 column, indicating its excellent separation performance. Besides, the SiO2@rLZU1 column also exhibited great repeatability with intraday RSDs of the retention time of three anilines less than 0.31% (n = 6) and peak area less than 1.63% (n = 6). On the SiO2@rLZU1 column, satisfied results were achieved in the separation of real samples such as fullerenes and coking wastewater, suggesting the great potential of the as-synthesized stationary phase in HPLC applications.

18.
Zhongguo Dang Dai Er Ke Za Zhi ; 22(12): 1273-1278, 2020 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-33327997

RESUMO

OBJECTIVE: To study the application of ponderal index (PI), body mass index (BMI), mid-arm circumference/head circumference (MAC/HC), and Clinical Assessment of Nutritional Status (CANS) score in assessing the nutritional status of neonates at birth, and to find a simple and reliable scheme for the assessment of fetal nutritional status. METHODS: PI, BMI, MAC/HC, and CANS were used to assess the nutritional status of full-term infants and preterm infants shortly after birth. The assessment results of these methods were analyzed. RESULTS: Among the 678 full-term infants, 61, 102, 47, and 131 were diagnosed with malnutrition by PI, BMI, MAC/HC, and CANS respectively. Among the 140 preterm infants, 30, 87, 9, and 112 were diagnosed with malnutrition by PI, BMI, MAC/HC, and CANS respectively. The combination of BMI and CANS had a detection rate of 99.3% in full-term infants and 100% in preterm infants. Compared with the single method, the combination significantly improved the detection rate of malnutrition (P < 0.05), while there was no significant difference between the combination of BMI+CANS and the combination of PI+BMI+CANS (P > 0.05). CONCLUSIONS: The combination of BMI+CANS can reduce the rate of missed diagnosis of fetal malnutrition. It is therefore a simple and reliable method for the assessment of fetal malnutrition.


Assuntos
Transtornos da Nutrição Fetal/diagnóstico , Avaliação Nutricional , Índice de Massa Corporal , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Estado Nutricional
19.
World J Gastroenterol ; 26(45): 7204-7221, 2020 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-33362377

RESUMO

BACKGROUND: Esophageal varices (EV) are the most fatal complication of chronic hepatitis B (CHB) related cirrhosis. The prognosis is poor, especially after the first upper gastrointestinal hemorrhage. AIM: To construct nomograms to predict the risk and severity of EV in patients with CHB related cirrhosis. METHODS: Between 2016 and 2018, the patients with CHB related cirrhosis were recruited and divided into a training or validation cohort at The First Affiliated Hospital of Wenzhou Medical University. Clinical and ultrasonic parameters that were closely related to EV risk and severity were screened out by univariate and multivariate logistic regression analyses, and integrated into two nomograms, respectively. Both nomograms were internally and externally validated by calibration, concordance index (C-index), receiver operating characteristic curve, and decision curve analyses (DCA). RESULTS: A total of 307 patients with CHB related cirrhosis were recruited. The independent risk factors for EV included Child-Pugh class [odds ratio (OR) = 7.705, 95% confidence interval (CI) = 2.169-27.370, P = 0.002], platelet count (OR = 0.992, 95%CI = 0.984-1.000, P = 0.044), splenic portal index (SPI) (OR = 3.895, 95%CI = 1.630-9.308, P = 0.002), and liver fibrosis index (LFI) (OR = 3.603, 95%CI = 1.336-9.719, P = 0.011); those of EV severity included Child-Pugh class (OR = 5.436, 95%CI = 2.112-13.990, P < 0.001), mean portal vein velocity (OR = 1.479, 95%CI = 1.043-2.098, P = 0.028), portal vein diameter (OR = 1.397, 95%CI = 1.021-1.912, P = 0.037), SPI (OR = 1.463, 95%CI = 1.030-2.079, P = 0.034), and LFI (OR = 3.089, 95%CI = 1.442-6.617, P = 0.004). Two nomograms (predicting EV risk and severity, respectively) were well-calibrated and had a favorable discriminative ability, with C-indexes of 0.916 and 0.846 in the training cohort, respectively, higher than those of other predictive indexes, like LFI (C-indexes = 0.781 and 0.738), SPI (C-indexes = 0.805 and 0.714), ratio of platelet count to spleen diameter (PSR) (C-indexes = 0.822 and 0.726), King's score (C-indexes = 0.694 and 0.609), and Lok index (C-indexes = 0.788 and 0.700). The areas under the curves (AUCs) of the two nomograms were 0.916 and 0.846 in the training cohort, respectively, higher than those of LFI (AUCs = 0.781 and 0.738), SPI (AUCs = 0.805 and 0.714), PSR (AUCs = 0.822 and 0.726), King's score (AUCs = 0.694 and 0.609), and Lok index (AUCs = 0.788 and 0.700). Better net benefits were shown in the DCA. The results were validated in the validation cohort. CONCLUSION: Nomograms incorporating clinical and ultrasonic variables are efficient in noninvasively predicting the risk and severity of EV.


Assuntos
Varizes Esofágicas e Gástricas , Hepatite B Crônica , Varizes Esofágicas e Gástricas/diagnóstico , Varizes Esofágicas e Gástricas/epidemiologia , Varizes Esofágicas e Gástricas/etiologia , Hepatite B Crônica/complicações , Humanos , Cirrose Hepática/complicações , Cirrose Hepática/diagnóstico , Nomogramas , Veia Porta , Curva ROC
20.
Aging (Albany NY) ; 12(21): 21971-21991, 2020 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-33159017

RESUMO

The purpose of this study was to identify a specific circular RNA and to investigate its regulatory mechanism in intervertebral disc degeneration (IDD). CircGLCE was selected after microarray analyses and was further analysed by RT-qPCR and FISH. CircGLCE was found to stably exist in the cytoplasm of nucleus pulposus (NP) cells. It was downregulated in IDD. After silencing CircGLCE, its function was assessed with RT-qPCR, immunofluorescence analysis and flow cytometry. Knockdown of CircGLCE promoted apoptosis and induced the expression of matrix-degrading enzymes in NP cells. CircGLCE served as a miR-587 sponge in NP cells. Inhibiting miR-587 counteracted the IDD-enhancing effect caused by silencing CircGLCE. STAP1 served as the miRNA target that mediated the functions of miR-587. In an IDD mouse model, the in vivo effects of overexpressing CircGLCE on IDD were confirmed by imaging techniques, TUNEL staining, FISH, western blotting, H&E staining and immunohistochemistry. Thus, CircGLCE attenuates IDD by inhibiting the apoptosis of NP cells and ECM degradation through the targeting of miR-587/STAP1. CircGLCE may be a potential therapeutic target for IDD treatments.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Apoptose , Matriz Extracelular/patologia , Degeneração do Disco Intervertebral/metabolismo , MicroRNAs/metabolismo , Núcleo Pulposo/metabolismo , RNA Circular/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Células Cultivadas , Modelos Animais de Doenças , Matriz Extracelular/metabolismo , Feminino , Regulação da Expressão Gênica , Humanos , Degeneração do Disco Intervertebral/genética , Degeneração do Disco Intervertebral/patologia , Masculino , Camundongos Endogâmicos C57BL , MicroRNAs/genética , Pessoa de Meia-Idade , Núcleo Pulposo/patologia , RNA Circular/genética , Estudos Retrospectivos , Transdução de Sinais
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