Peptidomics analysis of enzymatic hydrolysis beef

Dan Qin,Liping Wang,Rui Fang,Ziteng Yu,Li Mo,Min Liu 한국식품과학회 2022 Food Science and Biotechnology Vol.31 No.10

In this study, we investigated the changes in the composition of peptides during the digestion of tenderized beef treated with commercial proteinase K, flavourzyme, and bromelain. The degree of hydrolysis (DH) values before and after simulating gastric digestion were highest with proteinase K treatment. In the proteinase K-treated sample, the highest number of missing peptides was identified after gastrointestinal digestion. Additionally, the maximum number of new peptides was identified during gastric digestion. The flavourzyme is the only exopeptidase among the three enzymes, and the sample treated with it could produce more unique peptides after gastrointestinal digestion. Enzymatic tenderization altered the peptide composition and bioactivity of beef proteins during gastrointestinal digestion. The number of peptides, as well as unique peptides in the protease-treated sample, were more than those in control through gastric digestion. In contrast, the opposite was observed post gastrointestinal digestion.

T-SPOT.TB for Detection of Tuberculosis Infection among Hematological Malignancy Patients and Hematopoietic Stem Cell Transplant Recipients

Qin, Li-Li,Wang, Qin-Rong,Wang, Qian,Yao, Hong,Wen, Li-Jun,Wu, Li-Li,Ping, Na-Na,Xie, Jun-Dan,Chen, Mei-Yu,Chen, Su-Ning Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.12

The diagnosis of latent Mycobacterium tuberculosis infection (LTBI) is recommended in hematological malignancy patients and before hematopoietic stem cell transplantation (Guidelines for the prevention and management of infectious complications of solid organ transplantation, 2004). Compared to traditional methods such as tuberculin skin test (TST), T-SPOT.TB has been shown to be more specific. In the present study we enrolled 536 patients for whom T-SPOT.TB was performed, among which 295 patients also received the TST test. The agreement (79%) between T-SPOT.TB and TST was poor (x=0.274, P<0.001). The patients with positive T-SPOT.TB results numbered 62 (11.6%), in which only 20 (48.8%) of the 41 receiving the TST test had positive results. A majority of the patients with T-SPOT.TB positive results had some other evidence ofTB, such as TB history, clinical symptoms and an abnormal chest CT scan. Active TB was found in 9 patients, in which 2 had negative TST results. We followed up the patients and no one developed active TB. Our study suggested that the T-SPOT.TB may be more useful for screening LTBI and active TB in hematological malignancy patients and hematopoietic stem cell transplant recipients than the TST test.

Selective miRNA Expression Profile in Chronic Myeloid Leukemia K562 Cell-derived Exosomes

Feng, Dan-Qin,Huang, Bo,Li, Jing,Liu, Jing,Chen, Xi-Min,Xu, Yan-Mei,Chen, Xin,Zhang, Hai-Bin,Hu, Long-Hua,Wang, Xiao-Zhong Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.12

Background: Chronic myeloid leukemia (CML) is a myeloproliferative disorder of hematopoietic stem cell scarrying the Philadelphia (Ph) chromosome and an oncogenic BCR-ABL1 fusion gene. The tyrosine kinase inhibitor (TKI) of BCR-ABL1 kinase is a treatment of choice for control of CML. Objective: Recent studies have demonstrated that miRNAs within exosomes from cancer cells play crucial roles in initiation and progression. This study was performed to assess miRNAs within exosomes of K562 cells. Methods: miRNA microarray analysis of K562 cells and K562 cell-derived exosomes was conducted with the 6th generation miRCURYTM LNA Array (v.16.0). Gene ontology and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were also carried out. GO terms and signaling pathways were categorized into 66 classes (including homophilic cell adhesion, negative regulation of apoptotic process, cell adhesion) and 26 signaling pathways (such as Wnt). Results: In exosomes, 49 miRNAs were up regulated as compared to K562 cells, and two of them were further confirmed by quantitative real-time PCR. There are differentially expressed miRNAs between K562 cell derived-exosomes and K562 cells. Conclusion: Selectively expressed miRNAs in exosomes may promote the development of CML via effects on interactions (e.g. adhesion) of CML cells with their microenvironment.

EBV-miR-BHRF1-1 Targets p53 Gene: Potential Role in Epstein-Barr Virus Associated Chronic Lymphocytic Leukemia

Dan-Min Xu,Yi-Lin Kong,Li Wang,Hua-Yuan Zhu,Jia-Zhu Wu,Yi Xia,Yue Li,Shu-Chao Qin,Lei Fan,Jian-Yong Li,Jin-Hua Liang,Wei Xu 대한암학회 2020 Cancer Research and Treatment Vol.52 No.2

Purpose The purpose of this study was to investigate the prognostic impact of Epstein-Barr virus (EBV)–microRNA (miRNA, miR)-BHRF1-1 with chronic lymphocytic leukemia (CLL) as well as role of EBV-miR-BHRF1-1 in p53 gene. Materials and Methods Quantitative reverse transcription–polymerase chain reaction and western blotting were used to quantify EBV-miR-BHRF1-1 and p53 expression in cultured CLL. Results p53 aberration was associated with the higher expression level of EBV-miR-BHRF1-1 (p < 0.001) which was also an independent prognostic marker for overall survival (p=0.028; hazard ratio, 5.335; 95% confidence interval, 1.193 to 23.846) in 97 newly-diagnosed CLL patients after adjusted with International Prognostic Index for patients with CLL. We identified EBV-miR-BHRF1-1 as a viral miRNA regulator of p53. EBV-miR-BHRF1-1 repressed luciferase reporter activity by specific interaction with the seed region within the p53 3- untranslated region. Discordance of p53 messenger RNA and protein expression was associated with high EBV-miR-BHRF1-1 levels in CLL patients and cell lines. EBV-miR-BHRF1- 1 inhibition upregulated p53 protein expression, induced cell cycle arrest and apoptosis and decreased cell proliferation in cell lines. EBV-miR-BHRF1-1 mimics downregulated p53 protein expression, decreased cell cycle arrest and apoptosis, and induced cell proliferation in cell lines. Conclusion This study supported the role of EBV-miR-BHRF1-1 in p53 regulation in vitro. Our results support the potential of EBV-miR-BHRF1-1 as a therapeutic target in EBV-associated CLL with p53 gene aberration.

Corrosion behavior of the Mg₆₅Cu₂₅Gd₁₀ bulk amorphous alloys

Qin, F.X.,Bae, G.T.,Dan, Z.H.,Lee, H.,Kim, N.J. Elsevier 2007 Materials science & engineering. properties, micro Vol.449 No.-

<P><B>Abstract</B></P><P>The corrosion behavior of the Mg<SUB>65</SUB>Cu<SUB>25</SUB>Gd<SUB>10</SUB> (numbers indicate at.%) bulk amorphous alloy as well as its crystalline counterpart and pure Mg investigated by electrochemical measurements. Potentiodynamic polarization tests and electrochemical impedance spectroscopy were carried out in 0.2M borate buffer solution, 0.02M NaCl solution and 0.1M NaOH solution. Both amorphous and crystalline alloys were spontaneously passivated at significantly low passivation current density in borate buffer solution and sodium hydroxide solution. Surface morphology and composition information after polarization samples were characterized using scanning electron microscopy and energy disperse X-ray. Mg<SUB>65</SUB>Cu<SUB>25</SUB>Gd<SUB>10</SUB> bulk amorphous alloy shows higher corrosion resistance than its crystalline counterpart due to the absence of the heterogeneities in the former On the other hand, in Cl<SUP>−</SUP> containing solution, both amorphous and crystalline alloys are active dissolved at high current density due the presence of aggressive Cl<SUP>−</SUP> ion in solution.</P>

Enhancement of the antioxidant and hypolipidemic activities of Puerariae radix by fermentation with Aspergillus niger

Qin Huang,Hao Zhang,Dan Xue 한국식품과학회 2019 Food Science and Biotechnology Vol.28 No.4

Puerariae radix (PR) is a traditional Chinesefood and medicine. In this study, the chemical profile andbioactivities of PR fermented with Aspergillus niger (PFA)were investigated. Based on HPLC analysis, PFA chemicalprofile changed and total phenols increased by 12.5% relativeto PR. Consequently, the in vitro antioxidant activitysignificantly improved. According to the blood lipid analysisin mice, PFA showed a better ability to inhibit theincreased blood lipid levels induced by Triton WR-1339than PR. In a quantitative real-time PCR (qRT-PCR) study,PFA up-regulated cholesterol 7-alpha hydroxylase(CYP7A1) and low-density lipoprotein receptor mRNAexpression, which were 50% and 44.8% higher than thelevels induced by high-dose PR. Conversely, 3-hydroxy-3-methylglutaryl-CoA reductase (HMGCoAR) mRNAexpression was down-regulated to 46.8% lower than thelevels induced by high-dose PR. The qRT-PCR resultssuggested that PFA displayed better hypolipidemic activitythan PR, due to its superior ability to regulate mRNAexpression.

Somatic embryos cultures of Vitis amurensis Rupr. in air-lift bioreactors for the production of biomass and resveratrol

Dan Sun,Changyu Li,Hongyan Qin,Qingtian Zhang,Yiming Yang,Jun Ai 한국식물학회 2016 Journal of Plant Biology Vol.59 No.5

Resveratrol are the most important bioactive compounds found in Vitis amurensis. In this study, a somatic embryo induction system for V. amurensis was established in air-lift bioreactors for the production of biomass and resveratrol. The somatic embryos biomass growth was low on solid medium (69.60 g L−1) compared to in liquid medium in bioreactor (329.45 g L−1). Bioreactor cultures were found to be superior compared with solid medium culture not only in terms of biomass but also resveratrol productivity. Various culture parameters, including culture method, inoculum density, carbon source, and organic compounds were optimized. An inoculum density of 20 g L−1 embryogenic calli was found suitable for the accumulation of biomass and resveratrol production, whereas 10 g L−1 embryogenic calli increased the amount of resveratrol per fresh weight in somatic embryos. For bioreactor culturing, sucrose was an optimum carbon source and 500 mg L–1 casein hydrolysate acid was conducive to the biomass and resveratrol production. This result indicates that an efficient protocol for the large-scale production of resveratrol can be achieved by bioreactor culturing of V. amurensis somatic embryos and can be used as a source of medicinal raw materials.

A New Overlap Current Restraining Method for Current-source Rectifier

Qin, Haihong,Liu, Qing,Zhang, Ying,Zhang, Xin,Wang, Dan The Korean Institute of Power Electronics 2018 JOURNAL OF POWER ELECTRONICS Vol.18 No.2

To ensure a DC current path and avoid large voltage overshoot of the DC-link inductor, alternating PWM pulses in the current-source rectifier should be supplemented by overlap time, which generates an overlap current and causes input current distortion. In this study, the influence of overlap time is illustrated by comparing the AC-side current before and after overlap time is added. The overlap current distribution caused by overlap time is discussed under different modulation carriers, including triangle carrier, positive-going carrier, and negative-going carrier. The quantitative relationship between the extra harmonics of the AC-side current and overlap time is based on the Fourier analysis. Based on the commutation analysis, a new carrier modulation scheme that can restrain overlap current is proposed. A 3 kW prototype is established to verify the effectiveness of the influence of overlap time and the proposed restraining modulation scheme.

Sulfhydryl Cotton Enrichment Separation-Determination of Silver in Geological Samples by ICP-MS

Dan Li,Zhifei Zhao,Qin Chu,Jindong Fang 대한화학회 2011 Bulletin of the Korean Chemical Society Vol.32 No.10

A rapid and inexpensive method was developed for the determination of trace silver in geological samples by using sulfhydryl cotton coupled with ICP-MS. The interferences such as ^90Zr, ^92Mo and ^93Nb on silver were investigated in detail. Sulfhydryl cotton was found to be an effective adsorbent for separation of interferences for Ag in the solutions. Excellent agreements with the certified values were obtained for all the certified reference materials. The memory effects of Ag by ICP-MS were examined by using different agents, including water, nitric acid, and HCl-thiourea to all standards/samples. The agents also acted as cleansing solutions. A combination of HCl with thiourea gave the minimum memory effect. For comparison of results, a proposed Chinese Geology Survey procedure DC-ARC-AES and a direct determination pretreatment method of ICP-MS (water bath- auqa regia digestion) were studied. Under optimal conditions, the detection limits of our method for ^107Ag and ^109Ag were 1.2 ng/g and 1.3 ng/g, which offered much better accuracy for some difficult analysis geological samples such as GBW07604, GBW07605.

Preparation and High Degradation Activity of Supported Nano-Bi2WO6-TiO2/Nickel Foam Photocatalyst

Qin Tong,Ya-Mei Dong,Xiao-Jia Wang,Peng Yan,Dan-Nong He 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2015 NANO Vol.10 No.6

The supported nano-Bi2WO6–TiO2/nickel foam photocatalyst was synthesized via spraying method with silica sol as a binder. The as-prepared photocatalyst with large surface and thermal stability exhibited enhanced photocatalytic performance for degradation of Rhodamine B (RhB) solution in sunlight irradiation. The results showed that the RhB solution could be degraded to 71.6% within 60 min, exhibiting that improved photocatalytic activity increased by 77.6%, compared with that of pure Bi2WO6–TiO2 nanoparticles. Its high photocatalytic activity was due to the presence of nickel foam in the catalytic process, making the Bi2WO6–TiO2 highly dispersed and increasing the contact area of the photocatalysts with the organic pollutants. At the same time, a possible photocatalytic mechanism for the enhanced photocatalytic performance was investigated.