Lipidomic profiling of Skipjack tuna (Katsuwonus pelamis) by ultrahigh-performance liquid chromatography coupled to high resolution mass spectrometry

Hu, Lingping,Hu, Zhiheng,Chin, Yaoxian,Yu, Haixia,Xu, Jianhong,Zhou, Jianwei,Liu, Donghong,Kang, Mengli,Hu, Yaqin The Korean Society of Fisheries and Aquatic Scienc 2022 Fisheries and Aquatic Sciences Vol.25 No.3

A method of ultrahigh performance liquid chromatography coupled to high resolution mass spectrometry (UPLC-HRMS) was established for characterization of the lipid profile of Skipjack tuna. Over 300 lipid molecular species were identified through cross-acquisition in both positive and negative ion mode. Phospholipids (PLs) were dominant in Skipjack tuna. Lysophosphatidylethanolamine (LPE), phosphatidylethanolamine (PE), lysophosphatidylcholine (LPC) and phosphatidylcholine (PC) were the main lipid molecular species in PLs, accounting for 89.24% of the total PLs. The ratio of sphingolipids (SLs) and glycerolipids (GLs) were considerable, accounting for 12.30% and 13.60% of the total lipids respectively. Ceramide (Cer) was the main lipid molecular species of SLs, accounting for 64.96% of total SLs, followed by sphingomyelin (SM), accounting for 25.45% of total SLs. Ether diglycerides (ether DG) were the main lipid molecular species of GLs (97.83%). The main fatty acids (FAs) are unsaturated fatty acids (UFAs) in Skipjack tuna. Besides, a new FAs class branched fatty acid esters of hydroxy fatty acids (FAHFA) was detected, together with the FA. The active lipids identified in this study can be used to evaluate the nutritional value of Skipjack tuna.

Suppression of Ku80 Correlates with Radiosensitivity and Telomere Shortening in the U2OS Telomerase-negative Osteosarcoma Cell Line

Hu, Liu,Wu, Qin-Qin,Wang, Wen-Bo,Jiang, Huan-Gang,Yang, Lei,Liu, Yu,Yu, Hai-Jun,Xie, Cong-Hua,Zhou, Yun-Feng,Zhou, Fu-Xiang Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.2

Ku70/80 heterodimer is a central element in the nonhomologous end joining (NHEJ) DNA repair pathway, Ku80 playing a key role in regulating the multiple functions of Ku proteins. It has been found that the Ku80 protein located at telomeres is a major contributor to radiosensitivity in some telomerase positive human cancer cells. However, in ALT human osteosarcoma cells, the precise function in radiosensitivity and telomere maintenance is still unknown. The aim of this study was to investigate the effects of Ku80 depletion in the U2OS ALT cell line cell line. Suppression of Ku80 expression was performed using a vector-based shRNA and stable Ku80 knockdown in cells was verified by Western blotting. U2OS cells treated with shRNA-Ku80 showed lower radiobiological parameters (D0, Dq and SF2) in clonogenic assays. Furthermore, shRNA-Ku80 vector transfected cells displayed shortening of the telomere length and showed less expression of TRF2 protein. These results demonstrated that down-regulation of Ku80 can sensitize ALT cells U2OS to radiation, and this radiosensitization is related to telomere length shortening.

Effect of different concentrations of hypotaurine on melanosis and quality of Pacific white shrimp (Penaeus vannamei) during refrigeration

Zhou, Jiaying,Ying, Yubin,Zhou, Yaqi,Li, Gaoshang,Hu, Yaqin The Korean Society of Fisheries and Aquatic Scienc 2022 Fisheries and Aquatic Sciences Vol.25 No.4

Effect of different concentrations of hypotaurine (HTU) on melanosis and quality of shrimps during 10 d storage in ice were studied. During refrigeration, the total plate count and total volatile basic nitrogen of shrimps treated with 20 g/L HTU were the lowest, and the hardness and microstructure were the best. Moreover, the score of melanoses, pH and total bile acid of shrimps treated with 20 g/L HTU were also low. Sensory evaluation showed that HTU treatment could make the shelf life of shrimps 3-4 days longer compared with the control. Based on the above physical and chemical indexes, 20 g/L HTU showed great potential as a safe inhibitor in the treatment of shrimps' melanosis.

Molecular Cloning and Characterization of a Novel Exo-β-1,3-Galactanase from Penicillium oxalicum sp. 68

Zhou, Tong,Hu, Yanbo,Yan, Xuecui,Cui, Jing,Wang, Yibing,Luo, Feng,Yuan, Ye,Yu, Zhenxiang,Zhou, Yifa The Korean Society for Microbiology and Biotechnol 2022 Journal of microbiology and biotechnology Vol.32 No.8

Arabinogalactans have diverse biological properties and can be used as pharmaceutical agents. Most arabinogalactans are composed of β-(1→3)-galactan, so it is particularly important to identify β-1,3-galactanases that can selectively degrade them. In this study, a novel exo-β-1,3-galactanase, named PoGal3, was screened from Penicillium oxalicum sp. 68, and hetero-expressed in P. pastoris GS115 as a soluble protein. PoGal3 belongs to glycoside hydrolase family 43 (GH43) and has a 1,356-bp gene length that encodes 451 amino acids residues. To study the enzymatic properties and substrate selectivity of PoGal3, β-1,3-galactan (AG-P-I) from larch wood arabinogalactan (LWAG) was prepared and characterized by HPLC and NMR. Using AG-P-I as substrate, purified PoGal3 exhibited an optimal pH of 5.0 and temperature of 40℃. We also discovered that Zn²⁺ had the strongest promoting effect on enzyme activity, increasing it by 28.6%. Substrate specificity suggests that PoGal3 functions as an exo-β-1,3-galactanase, with its greatest catalytic activity observed on AG-P-I. Hydrolytic products of AG-P-I are mainly composed of galactose and β-1,6-galactobiose. In addition, PoGal3 can catalyze hydrolysis of LWAG to produce galacto-oligomers. PoGal3 is the first enzyme identified as an exo-β-1,3-galactanase that can be used in building glycan blocks of crucial glycoconjugates to assess their biological functions.

A New Phenolic Compound from Dendrobium longicornu

Hu, Jiangmiao,Fan, Weiwei,Zhou, Lu,Zhao, Youxing,Zhou, Jun Korean Chemical Society 2010 Bulletin of the Korean Chemical Society Vol.31 No.10

Effect of Association on Rheological Behaviors in the Non-Aqueous Solutions of Semi-Flexible Cellulose Derivatives

Hu Zhou,맹일호,구용환,김혜원,박지현,강현석,이병철,박용해,김상호 한국고분자학회 2013 Macromolecular Research Vol.21 No.11

The rheology of cellulose derivatives dissolved in highly viscous solvent was studied. Results demonstrated that a concentration-dependent transition occurred at ca. 10 vol% for ethyl cellulose, and at ca. 2.0 vol% for hydroxypropyl cellulose. Below the transition point, steady shear viscosity of solutions showed weak concentration dependency. The exponent of the power law model was about 3.7. Above the transition, the viscosity was strongly dependent on the concentration. Further studies showed that such a transition strongly depended on the association between chains. Above the transition point, their long-time dynamics were dominated by the hydrogen bonds acting as the transient cross-links between chains. While below this point, long-time dynamics were governed by the percolation statistics. As a result, their viscosities indicated different concentration dependence relationships. Our studies showed that the entanglement and association behaviors were different, for the flexible and semi-flexible chains.

Thermal Sensitive Polyurethane Membranes with Desirable Switch Temperatures

Hu Zhou,Jianxian Zeng,Haojun Fan,Yuansen Liu,Jian Zhou 한국고분자학회 2010 Macromolecular Research Vol.18 No.11

Chemical synthesis and physical blending methods were used to prepare thermal sensitive polyurethanes (TSPU) with single or double thermal switches. In the design of the formula, polycaprolactone diol (PCL) with a molecular weight 10,000 and 4,000 and polytetramethylene glycol (PTMG) with a molecular weight 3,000 and 2,000 were used as the soft segments. The effects of the crystallinity and compatibility of the soft segments on the phase transition temperatures of the soft segments of TSPU (defined as switch temperature, Ts) were investigated in detail. To examine the thermal sensitivity of the thermal switch, water vapor permeability (WVP) experiments were performed to investigate the mass transport as a function of temperature. Differential scanning calorimetry (DSC)indicated that all the original TSPUs had a phase separated structure that was independent of the phase transition temperature of the soft and hard segments. The Ts values are determined mostly by the melting temperatures of the soft segments. On the other hand, for their blends, the Ts values are determined by the compatibility of the soft segments and the blending weight ratio. The blends of the PCL-based TSPUs showed good compatibility and single Ts due to the similar structure of the soft segments (just a difference in molecular weight), whereas for the PCL-based and PTMG-based TSPUs (the molecular structure is very different) blends, the Ts two independent values and blending weight ratio-dependent features due to the difference in the structure of the soft segments. Water vapor permeability analysis revealed the mass transport showed switching features to thermal stimuli, i.e. when the temperature reached the Ts, the WVPs of membranes showed rapid changes. On the other hand, the sensitivity of the thermal switch characterized by WVP improvement showed a dependence on the degree of crystallinity of the soft segments,i.e. well-organized soft segment structure is beneficial for improving the thermal sensitivity. Overall, TSPU membranes with a single Ts and different thermal sensitivity can be prepared using different crystalline poly-diols as the soft segments and blending two types of TSPUs with similar soft segments in the molecule structure, whereas TSPU with a double Ts can be achieved easily by blending two types of TSPUs with different soft segments.

Establishing a Nomogram for Stage IA-IIB Cervical Cancer Patients after Complete Resection

Zhou, Hang,Li, Xiong,Zhang, Yuan,Jia, Yao,Hu, Ting,Yang, Ru,Huang, Ke-Cheng,Chen, Zhi-Lan,Wang, Shao-Shuai,Tang, Fang-Xu,Zhou, Jin,Chen, Yi-Le,Wu, Li,Han, Xiao-Bing,Lin, Zhong-Qiu,Lu, Xiao-Mei,Xing, H Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.9

Background: This study aimed to establish a nomogram by combining clinicopathologic factors with overall survival of stage IA-IIB cervical cancer patients after complete resection with pelvic lymphadenectomy. Materials and Methods: This nomogram was based on a retrospective study on 1,563 stage IA-IIB cervical cancer patients who underwent complete resection and lymphadenectomy from 2002 to 2008. The nomogram was constructed based on multivariate analysis using Cox proportional hazard regression. The accuracy and discriminative ability of the nomogram were measured by concordance index (C-index) and calibration curve. Results: Multivariate analysis identified lymph node metastasis (LNM), lymph-vascular space invasion (LVSI), stromal invasion, parametrial invasion, tumor diameter and histology as independent prognostic factors associated with cervical cancer survival. These factors were selected for construction of the nomogram. The C-index of the nomogram was 0.71 (95% CI, 0.65 to 0.77), and calibration of the nomogram showed good agreement between the 5-year predicted survival and the actual observation. Conclusions: We developed a nomogram predicting 5-year overall survival of surgically treated stage IA-IIB cervical cancer patients. More comprehensive information that is provided by this nomogram could provide further insight into personalized therapy selection.

Indirect Detection of Rotor Position of Switched Reluctance Motor Based on Flux Linkage Analytic Model

Zhou, Yongqin,Hu, Bo,Wang, Hang,Jin, Ningzhi,Zhou, Meilan The Korean Institute of Electrical Engineers 2018 Journal of Electrical Engineering & Technology Vol.13 No.2

In this paper, a flux linkage model based on four magnetization curves fitting is proposed for three-phase 12/8 switched reluctance motor (SRM), with the analysis of the basic principle of flux detection method and function analysis method. In the model, the single value function mapping relationship between position angle and flux is established, which can achieve a direct estimation of rotor position. The realization scheme of SRM indirect position detection system is presented. It is proved by simulation and experiment that the proposed scheme is suitable for rotor position detection of SRM, and has high accuracy of position estimation.

Polyurethane Membrane with Temperature- and pH-Controllable Permeability for Amino-Acids

Hu Zhou,Ruiping Xun,Kejian Wu,Zhihua Zhou,Bin Yu,Youxin Tang,Ning Li 한국고분자학회 2015 Macromolecular Research Vol.23 No.1

This work was focused on the investigation of the temperature- and pH-responsive polyurethane (PU)membranes and their permeability to amino-acids in response to environmental stimuli. The PU membrane wasprepared from a wet phase inversion method and a two-step solution polymerization from polycaprolactone diols(PCL), 4,4′-diphenylmethane diisocyanate (MDI), dimethylol propionic acid (DMPA), etc. The chemical structure,phase state, morphology and surface wettability of the membrane were characterized with Fourier transform infrared(FTIR) spectrometer, differential scanning calorimetry (DSC), scanning electron microscopy (SEM) and contactangle tester, respectively. The temperature and pH responses of the membrane were investigated by means of anamino-acid permeate experiment. The L-phenylalanine (L-Phe) was chosen as model amino-acids. The permeation of theL-Phe was measured using a dead-end flow filtration at varied temperatures and pH, and characterized by the permeateflux (J) and rejection coefficient (R). J of the L-Phe across the PU membrane increased with increasingtemperature and showed a sharp increase when temperature was raised to the crystalline melting temperature (Tm)of the soft segment of PU, while decreased with increasing pH and having a sharp decrease when pH reached thedissociation constant (pKa) of DMPA contained in PU macromolecules. While, the R behavior of L-Phe was justopposite from the results of J, which decreased with increasing temperature and increased with increasing pH,also showing the temperature and pH responses. Hopefully, the PU membrane with temperature- and pH-controllablepermeability has promising prospects in water treatment, membrane separation, drug delivery system, etc.