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1.
Chem Biodivers ; 18(7): e2100130, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34080308

RESUMO

The polysaccharides of the Chinese herbal medicine Dendrobium huoshanense exhibit anti-inflammatory effects in multiple organs through regulating the immune responses. In the present study, we constructed ulcerative colitis (UC) model rats using dextran sulfate sodium to investigate the anti-inflammatory effects of D. huoshanense polysaccharides (DHP). After oral administration of DHP for two weeks, the indices of UC symptoms, including the ratio of colon weight to length, Disease Activity Index (DAI), and Colon Mucosal Damage Index (CMDI), all decreased significantly compared with the UC model group. The histological sections also revealed better cell orders in DHP treatments than in the UC model rats. Moreover, in treatment with high dose of DHP (200 mg/kg), the treatment efficacy arrived the similar levels to those in the treatment with 300 mg/kg sulfasalazine, which is a typical medicine to treat UC. These results indicated that DHP has a high efficacy to treat UC in model rats. Furthermore, serum levels of interleukin-1ß, tumor necrosis factor-α, interleukin-17, and transforming growth factor-ß were assessed using the enzyme linked immunosorbent assay (ELISA) method, and the levels of nuclear factor-κB in colon tissue sections were determined using the immunohistochemical method. The results showed that all these indices decreased significantly after administration of DHP in UC model rats, which might be the mechanisms underlying the DHP-suppressed UC inflammation. Overall, this study indicated that DHP might be directly used to treat UC and is a promising source to develop novel drugs against UC.


Assuntos
Colite Ulcerativa/tratamento farmacológico , Dendrobium/química , Inflamação/prevenção & controle , NF-kappa B/antagonistas & inibidores , Polissacarídeos/farmacologia , Animais , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/metabolismo , Sulfato de Dextrana/administração & dosagem , Modelos Animais de Doenças , Feminino , Masculino , NF-kappa B/metabolismo , Polissacarídeos/química , Polissacarídeos/isolamento & purificação , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos
2.
Mikrochim Acta ; 185(1): 43, 2017 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-29594396

RESUMO

The authors have immobilized nanowires made from zirconium glycerolate (ZrGly) on magnetite (Fe3O4) nanoparticles by applying a solvothermal growth process using metal-glycerolate as a precursor. The structure and the dissolution-recrystallization mechanism of the resulting Fe3O4@ZrGly composite were investigated by attenuated total reflection-FTIR, energy-dispersive X-ray analysis, thermogravimetric analysis and solid-state cross polarization/magic angle spinning 13C NMR spectroscopy. The interaction between the zirconium glycerolate in Fe3O4@ZrGly and cis-diols leads to efficient adsorption of riboncleosides which then can be quantified by HPLC with UV detection. The sorbent was successfully applied to the selective enrichment of adenosine, cytidine, uridine and guanosine from spiked human urine samples. The detection limit of the method is in the range from 1.7 to 19 ng·mL-1 of nucleosides in spiked human urine, with relative standard deviations of lower than 12.4% and recoveries ranging from 90.6 to 113%. Graphical abstract Fe3O4@ZrGly with high selectivity towards ribonucleosides was designed and applied for quantitation of urinary ribonucleosides.


Assuntos
Nanopartículas de Magnetita/química , Nanofios/química , Ribonucleosídeos/isolamento & purificação , Zircônio/química , Adsorção , Glicerol/química , Humanos , Concentração de Íons de Hidrogênio , Limite de Detecção , Tamanho da Partícula , Ribonucleosídeos/urina , Microextração em Fase Sólida/métodos , Propriedades de Superfície
3.
Artigo em Inglês | MEDLINE | ID: mdl-27372913

RESUMO

Immobilized metal affinity chromatography (IMAC) technique is frequently used in the purification of histidine-tagged (His-tagged) recombinant proteins. In this study, nickel(II)-immobilized carboxyl cotton chelator (CCC-Ni2+) fibers was synthesized by a simple method based on the coordination effect between Ni2+ and carboxyl group. The nickel content of the CCC-Ni2+ fibers was determined to be 5 times larger than that of Ni2+-immobilized sulfhydryl cotton fiber (SCF-Ni2+) fibers developed in our previous work. The prepared CCC-Ni2+ fibers were then applied for the selective and rapid separation of His-tagged protein from escherichia coli (E. coli) cell lysates on the basis of the high affinity of Ni2+ to 6×His with a lab-in-syringe format. Benefiting from the good biological compatibility and high nickel content, the results showed that CCC-Ni2+ fibers were able to selectively capture His-tagged proteins from complex E. coli cell lysates and exhibited a relatively large adsorption capacity toward His-tagged protein. The recoveries of His-tagged GFP in E. coli cell lysates were in the range of 89.8%-106.7% with the relative standard deviations (RSDs) less than 9.4% (intra-day) and 10.3% (inter-day). Taken together, this efficient approach for the purification of recombinant proteins extends the application of CCC-based fibrous materials in biological analysis.


Assuntos
Cromatografia de Afinidade/instrumentação , Cromatografia de Afinidade/métodos , Histidina/química , Níquel/química , Proteínas Recombinantes de Fusão/isolamento & purificação , Quelantes/química , Fibra de Algodão , Proteínas Recombinantes de Fusão/análise , Proteínas Recombinantes de Fusão/química , Extração em Fase Sólida
4.
J Chromatogr A ; 1405: 188-92, 2015 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-26087962

RESUMO

In the current study, a novel nickel(II)-immobilized sulfhydryl cotton fiber (SCF-Ni(2+)) was prepared in a simple way based on the coordination effect between Ni(2+) and thiol group on the surface of SCF. The composition and element mapping of SCF-Ni(2+) fibers were demonstrated by energy-dispersive X-ray (EDX) spectroscopy. Based on the high affinity of Ni(2+) to 6×His on histidine-tagged (His-tagged) proteins, SCF-Ni(2+) fibers were then further used as an immobilized metal ion affinity chromatography (IMAC) adsorbent for selective binding and rapid separation of His-tagged proteins using an in- pipette-tip SPE format. Our results showed that SCF-Ni(2+) adsorbent can selectively capture His-tagged proteins from protein mixture and Escherichia coli cell lysates. Taken together, the developed method provides a rapid, convenient and efficient approach for the purification of His-tagged proteins.


Assuntos
Complexos de Coordenação/química , Fibra de Algodão , Histidina/química , Níquel/química , Proteínas Recombinantes/isolamento & purificação , Compostos de Sulfidrila , Cromatografia de Afinidade , Escherichia coli/metabolismo , Proteínas de Fluorescência Verde/química , Proteínas de Fluorescência Verde/isolamento & purificação , Proteínas de Fluorescência Verde/metabolismo , Ligação Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo
5.
Chemistry ; 21(11): 4450-6, 2015 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-25641232

RESUMO

A simple method was developed for the preparation of ordered mesoporous silica-carbon composite nanofibers (OMSCFs). The OMSCFs exhibited high carbon content, continuously long fibrous properties, uniform accessible mesopores, and a large surface area. The OMSCFs were also found to have ion-exchange capacity. On the basis of the size-exclusion effect of the mesopores and mixed-mode hydrophobic/ion-exchange interactions, the OMSCFs were applied for rapid enrichment of endogenous peptides by using a miniaturized solid-phase extraction format. The adsorption mechanism was studied, and the eluting solution was optimized with standard peptide/protein solutions and protein digests. Employing a successive three-step elution strategy, followed by LC-MS/MS analysis, led to excellent performance with this approach in the extraction and prefractionation of peptides from human serum.


Assuntos
Carbono/química , Nanofibras/química , Peptídeos/química , Dióxido de Silício/química , Humanos
6.
Analyst ; 140(5): 1731-8, 2015 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-25619730

RESUMO

A rapid analysis method by coupling carbon nanotube film (CNTF) microextraction with desorption corona beam ionization (DCBI) was developed for the determination of Sudan dyes (I-IV) and Rhodamine B in chilli oil samples. Typically, CNTF was immersed into the diluted solution of chilli oil for extraction, which was then placed directly under the visible plasma beam tip of the DCBI source for desorption and ionization. Under optimized conditions, five dyes were simultaneously determined using this method. Results showed that the analytes were enriched by the CNTF through the π-π interactions, and the proposed method could significantly improve the sensitivities of these compounds, compared to the direct analysis by DCBI-MS/MS. The method with a linear range of 0.08-12.8 µg g(-1) and good linear relationships (R(2) > 0.93) in a multiple reaction monitoring (MRM) mode was developed. Satisfactory reproducibility was achieved. Relative standard deviations (RSDs) were less than 20.0%. The recoveries ranged from 80.0 to 110.0%, and the limits of detection (LODs) were in the range of 1.4-21 ng g(-1). Finally, the feasibility of the method was further exhibited by the determination of five illegal dyes in chilli powder. These results demonstrate that the proposed method consumes less time and solvent than conventional HPLC-based methods and avoids the contamination of chromatographic column and ion source from non-volatile oil. With the help of a 72-well shaker, multiple samples could be treated simultaneously, which ensures high throughput for the entire pretreatment process. In conclusion, it provides a rapid and high-throughput approach for the determination of such illicit additions in chilli products.


Assuntos
Capsicum/química , Corantes/análise , Aditivos Alimentares/análise , Nanotubos de Carbono/química , Óleos de Plantas/análise , Microextração em Fase Sólida/métodos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Compostos Azo/análise
7.
J Geriatr Cardiol ; 11(3): 192-9, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25278966

RESUMO

BACKGROUND: The relationship between lipids and coronary artery disease has been well established. However, this is not the case between lipids and heart failure. Ironically, high lipid levels are associated with better outcomes in heart failure, but the mechanisms underlying the phenomenon are not fully understood. This study was performed to test the hypothesis that reduced intestinal lipid absorption due to venous congestion may lead to low lipid levels. METHODS: We collected data of clinical characteristics, echocardiograph, and lipid profile in 442 unselected patients with congestive heart failure. Correlations between lipid levels [including total cholesterol (TCL), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), and triglycerides (TG)] and right ventricle end diastolic diameter (RVEDD), left ventricle end diastolic diameter (LVEDD), right atrium diameter (RA), left atrium diameter (LA), or left ventricle ejection fraction (LVEF) were analyzed using Pearson correlation and partial correlation. RVEDD, LVEDD, RA, and LA were indexed to the body surface area. RESULTS: There was a significantly inverse correlation between TCL levels and RVEDD (r = -0.34, P < 0.001) and RA (r = -0.36, P < 0.001). Other lipids such as LDL-C, HDL-C, and TG had a similar inverse correlation with RVEDD and RA. All these correlations remained unchanged after adjusting for age, gender, smoking status, physical activity levels, comorbidities, and medication use. CONCLUSIONS: Lipid levels were inversely correlated to RVEDD in patients with congestive heart failure; however, because this was an observational study, further investigation is needed to verify our results as well as identify a causal relationship, if any.

8.
J Chromatogr A ; 1316: 23-8, 2013 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-24119757

RESUMO

Mesoporous silica embedded pipette tips (mSiO2-Tips) were successfully prepared by a simple method and applied to rapid enrichment of endogenous peptides for the first time. The prepared mSiO2-Tips showed low back pressure when solvent was pipetted up and down. As a result, mSiO2-Tip could selectively trap peptides and exclude high-MW proteins simultaneously based on size-exclusion mechanism due to the uniform mesopore structure of the sorbent bed. The in-pipette-tip SPE approach was proved to be easy-operation, sensitive and fast (less than 2 min) for the analysis of peptides, which was further successfully applied in the efficient enrichment of peptides from human plasma.


Assuntos
Peptídeos/isolamento & purificação , Dióxido de Silício/química , Extração em Fase Sólida , Acetonitrilas , Humanos , Peptídeos/sangue , Peptídeos/química , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Extração em Fase Sólida/instrumentação , Extração em Fase Sólida/métodos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
9.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 27(3): 333-4, 2010 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-20533277

RESUMO

OBJECTIVE: To identify a novel HLA-DRB1 allele in Chinese. METHODS: A novel HLA-DR allele was detected by PCR-SSP and SBT in a patient with leukemia. RESULTS: The sequence of the novel allele was different from all other known alleles. The novel allele differed from the closet matching allele HLA-DRB1*1404 by one nucleotide substitution in exon 2, at position 33 T>C, this resulted in an amino acid change from Tyr to His at codon 17. CONCLUSION: The novel allele is confirmed as a new HLA allele and it was officially named HLA-DRB1*1461 by WHO Nomenclature Committee in May, 2006.


Assuntos
Alelos , Antígenos HLA-DR/genética , Povo Asiático/genética , Cadeias HLA-DRB1 , Humanos , Reação em Cadeia da Polimerase , Análise de Sequência de DNA
10.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 17(3): 787-92, 2009 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-19549409

RESUMO

This study was aimed to investigate a beneficial approach for resolving the deficiency of blood source, preventing the infection resulting from blood transfusion and overcoming the knotty match of patients with rare blood group by using massive expansion of erythroid cells from cord blood CD34(+) cells in vitro. The CD34(+) cells from human cord blood were cultured in serum-free medium supplemented with stem cell factor (SCF), interleukin-3 (IL-3) and erythropoietin (EPO) for 1 week, then expansion and differentiation of CD34(+) cells into erythroid cells were supported by co-culture with human mesenchymal stem cells (MSCs) derived from bone marrow for 2 weeks. The results indicated that after culture for 23 days, the expansion multiple of total cell number reached 2.52 x 10(5), and over 95% of these cells were erythroid cells as compared with less than 1% of myelomonocytic (CD14(+) or CD15(+)) cells and megakaryocytic (CD41(+)) cells. However, the culture system without MSC support was significantly disadvantaged both in expansion ability and ratio of erythroid cells when compared with MSC supporting system. It is concluded that the erythroid cells can be produced from CD34(+) cells in large scale by culturing in the system comprised of cytokine sets and MSC feeders, in which MSCs can support the proliferation and differentiation of erythroid cells.


Assuntos
Técnicas de Cultura de Células/métodos , Diferenciação Celular , Sangue Fetal/citologia , Células-Tronco Hematopoéticas/citologia , Antígenos CD34 , Humanos
11.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 26(2): 216-8, 2009 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-19350520

RESUMO

OBJECTIVE: To investigate a recombination event occurring between the HLA-B and DRB1 loci in a Chinese family with a leukemia patient. METHODS: HLA class I (-A and -B) low resolution typing was carried out by polymerase chain reaction-sequence specific oligonucleotide, PCR-SSO). HLA class II low resolution typing was performed by PCR-sequence specific primer (PCR-SSP). And HLA class I and II high resolution typing was done by sequencing-based typing (SBT). Then the recombination event was analyzed by family study. RESULTS: The 2 haplotypes of the patient were A*3101-B*1301-DRB1*0701 and A*3303-B*4403-DRB1*1302. His father's 2 haplotypes were A*3001-B*1302-DRB1*0701 and A*3101-B*1301-DRB1*1501. Family study demonstrated that the HLA-A*3101-B*1301 was from one of his father's chromosome and the DRB1*0701 was from the other chromosome of his father. So the result indicated that the recombination event occurred between the HLA-B and -DRB1 loci during meiosis of his father and resulted in a new HLA haplotype that was transferred to the son. CONCLUSION: A HLA-B/DR recombination event occurring between the HLA-B and -DRB1 loci has been found in a Chinese family, which may help further study of the mechanism of HLA recombination.


Assuntos
Povo Asiático/genética , Antígenos HLA-A/genética , Antígenos HLA-B/genética , Antígenos HLA-DQ/genética , Antígenos HLA-DR/genética , Adolescente , Troca Genética/genética , Família , Feminino , Cadeias beta de HLA-DQ , Cadeias HLA-DRB1 , Humanos , Masculino , Linhagem , Reação em Cadeia da Polimerase , Recombinação Genética
12.
World J Gastroenterol ; 9(5): 1111-3, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12717868

RESUMO

AIM: To compare the efficiency of different plasmids as DNA vectors by cloning three HBsAg-encoded genes into two eukaryotic expression vectors, pRc/CMV and pSG5UTPL/Flag, and to express HBsAg S, MS, and LS proteins in SP2/0 cells, and to establish monoclone SP2/0 cell strains that are capable of expressing S or S2S proteins stably. METHODS: Segments of S, preS2-S, preS1-preS2-S genes of Hepatitis B virus were amplified by routine PCR and preS1-S fragment was amplified by Over-Lap Extension PCR. The amplified segments were cleaved with restricted endonuclease Hind III/Not I followed by ligation with pRc/CMV, or BamHI/EcoR I followed by ligation with pSG5UTPL/Flag. After the plasmid vectors were cleaved with the correspond enzymes, the amplified segments were inserted into pRc/CMV or pSG5UTPL/Flag plasmid vectors with T4 DNA ligase. KOZAK sequence was added before the initial ATG code of each fragment using specific primer. The inserted segments in the recombinant plasmids were sequenced after subcloning. BALB/c mice myeloma cells (SP2/0 cell line) were transfected with the recombinant plasmids. The expressions of the different recombinants were Compared by Western-blot, using a monoclonal anti-HBs antibody as the primary antibody and peroxidase-labeled multi-linker as the secondary. Stable SP2/0-pRc/CMV-S or SP2/0- pRc/CMV-MS clones were established through clone screening with G418. RESULTS: Fragments with anticipated size were harvested after PCR. After recombination and screening, the sequences of the inserted segments in the recombinants were confirmed to be S, preS2S, preS1-preS2S and preS1S encoding genes, determined by sequencing. The results of Western-blot hybridization were positive for the anticipated proteins. Among them, pRc/CMV-S or pRc/CMV-MS demonstrated the highest expressing their respective antigen. CONCLUSION: Eight recombinant plasmids expressing S, M, L or preS1S proteins are obtained. For hepatitis surface antigen expression in eukaryotic cells, the vector pRc/CMV is superior to pSG5UTPL/Flag, and pRc/CMV-S and pRc/CMV-MS are the most efficient in the pRc/CMV clones. SP2/0 cells stably expressing HBsAg are established, and may be used as target cells for evaluating the CTL activity of a DNA vaccine in vitro.


Assuntos
Genes Virais , Antígenos de Superfície da Hepatite B/genética , Vírus da Hepatite B/genética , Animais , Sequência de Bases , Linhagem Celular , Clonagem Molecular , DNA Viral/genética , Expressão Gênica , Vetores Genéticos , Vírus da Hepatite B/imunologia , Camundongos , Plasmídeos/genética , Precursores de Proteínas/genética , Transfecção
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