Kinetics Study of Enzymatic Hydrolysis of Paulownia by Dilute Acid, Alkali, and Ultrasonic-assisted Alkali Pretreatments

Xiao-kun Ye,Yuancai Chen 한국생물공학회 2015 Biotechnology and Bioprocess Engineering Vol.20 No.2

Paulownia, a fast-growing and high-fiber plant (cellulose: 41.66% and hemicellulose: 19.61%), has the potential to serve as an interesting source for production of bioethanol. The aim of this paper is to study and compare the kinetics of enzymatic hydrolysis of Paulownia pretreated by dilute acid (DA), alkali (AL) and ultrasonic-assisted alkali (UA). The enzymatic hydrolysis was performed at 50°C, atmospheric pressure with 40 FPU/g-cellulose cellulase and 80 CBU/g-cellulose cellobiase. The hydrolysis process can be successfully described by the Michaelis-Menten model under the three pretreatment conditions. Due to the high removal of lignin and increased porosity of the substrate, UA pretreatment is proved to be the most effective method in improving enzymatic saccharification, followed by DA pretreatment and alkali (AL) pretreatment. Inhibition constant KI of all experiments (DA: 2.16 g/L, AL: 3.12 g/L and UA: 1.83 g/L) suggests that glucose has a strong inhibition for enzymatic hydrolysis, for lower KI is proportional to higher inhibition performance. The experimental date fits well with kinetics model. This indicates that the model is suitable for performance monitoring, conditions optimization and process control at full-scale studies.

Long noncoding RNA atlas of the inflammation caused by asthma in mice

Ye Chen,Shou‑di He,Xiao‑dong Li,Zhi‑li Hu,Chao Zhang,Feng Xu 대한약학회 2020 Archives of Pharmacal Research Vol.43 No.4

There is little evidence regarding the roles oflong noncoding RNAs (lncRNAs) in inflammation caused byasthma. In this study, we successfully generated an asthmamouse model that was induced by ovalbumin (OVA). Theeffects of dexamethasone (Dex) treatment on lung tissuewere investigated using pathological and biochemicalmethods, including Diff-Quik staining, enzyme-linkedimmunosorbent assay (ELISA), hematoxylin–eosin (H&E)staining, and western blotting (WB). The inflammation waseffectively relieved with Dex treatment. High-throughputsequencing revealed that a total of 1490 lncRNAs were detected in lung tissue samples. Differential expressionanalysis revealed that the Dex group had 20 upregulatedand 15 downregulated lncRNAs compared with those inthe Model group. Moreover, nine differentially expressedand inflammation-related lncRNAs were verified by quantitativereal-time reverse transcription polymerase chainreaction (qRT-PCR). Furthermore, the regulation networksof these nine lncRNAs, their potential binding microRNA(miRNAs), and the putative target genes showed that theselncRNAs play important roles in the nuclear factor kappalight-chain-enhancer of activated B cells (NF-κB) signalingpathway. We further identified the expression levels of threepotential binding miRNAs by qRT-PCR. The results of thisstudy contribute to a better understanding of the functionsof lncRNAs in inflammation caused by asthma.

Molecular cloning and characterization of two novel DREB genes encoding dehydration-responsive element binding proteins in halophyte Suaeda salsa

Xiao-Bo Sun,Hong-Xiang Ma,Xin-Ping Jia,Yu Chen,Xiao-Qing Ye 한국유전학회 2015 Genes & Genomics Vol.37 No.2

The dehydration-responsive element-binding(DREB) proteins play an important role in regulatingexpression of stress-inducible genes under abiotic stresses. In this study, two genes encoding putative DREB proteins,named SsDREBa and SsDREBb, were cloned from halophyteSuaeda salsa L. using RACE method. The deducedSsDREBa and SsDREBb proteins contain a typical AP2/ERF domain. Multiple sequence alignments and phylogeneticanalysis revealed that the two SsDREB genes of S. salsa were highly similar in AP2/ERF domains at thenucleotide and amino acid levels and belong to the A-6subgroup of the DREB transcription factor subfamily. Asubcellular localization assay showed that both SsDREBslocalized to the nucleus. Yeast one-hybrid experimentstestified that both proteins were able to specifically bind tothe DRE sequence and activate the expression of the downstreamHIS reporter gene in yeast. Quantitative real-timePCR analysis demonstrated that under normal conditions,the expression level of SsDREBa was the most high in theroots and no SsDREBa mRNAs were detected in the stems;SsDREBb expressed at relatively higher levels in the leavesthan in the roots and stems. The expression of SsDREa andSsDREBb genes in S. salsa roots and leaves was remarkablyinduced by high-salt and dehydration treatments, butnot by cold and ABA, and exhibited stronger induction inroots and leaves, respectively. These results indicate thatthe SsDREBa and SsDREBb are novel stress-responsivetranscription factors, which are involved in the drought andhigh-salt stress responses through ABA-independent pathwaysand could be used for production of stress-toleranttransgenic crops.

Statistical experimental design optimization of rhamsan gum production by Sphingomonas sp. CGMCC 6833

Xiao-Ying Xu,Shu-Hao Dong,Sha Li,Xiao-Ye Chen,Ding Wu,Hong Xu 한국미생물학회 2015 The journal of microbiology Vol.53 No.4

Rhamsan gum is a type of water-soluble exopolysaccharideproduced by species of Sphingomonas bacteria. The optimalfermentation medium for rhamsan gum production bySphingomonas sp. CGMCC 6833 was explored definition. Single-factor experiments indicate that glucose, soybean meal,K2HPO4 and MnSO4 compose the optimal medium alongwith and initial pH 7.5. To discover ideal cultural conditionsfor rhamsan gum production in a shake flask culture, responsesurface methodology was employed, from which thefollowing optimal ratio was derived: 5.38 g/L soybean meal,5.71 g/L K2HPO4 and 0.32 g/L MnSO4. Under ideal fermentationrhamsan gum yield reached 19.58 g/L ± 1.23 g/L,42.09% higher than that of the initial medium (13.78 g/L ±1.38 g/L). Optimizing the fermentation medium results inenhanced rhamsan gum production.

Multilocus Sequence Typing and Virulence Factors Analysis of Escherichia coli O157 Strains in China

Xiao W. Ji,Ya L. Liao,Ye F. Zhu,Hai G. Wang,Ling Gu,Jiang Gu,Chen Dong,Hong L. Ding,Xu H. Mao,Feng C. Zhu,Quan M. Zou 한국미생물학회 2010 The journal of microbiology Vol.48 No.6

Escherichia coli O157:H7, an important food-borne pathogen, has become a major public health concern worldwide. The aim of this study was to investigate the molecular epidemiologic feature of E. coli O157:H7strains in China. 105 E. coli O157:H7 isolates were collected from various hosts and places over 9 years. A multilocus sequence typing scheme (MLST) was applied for bacteria genotyping and polymerase chain reaction (PCR) was used for virulence factor identification. Seven new MLST sequence types (STs), namely ST836, ST837, ST838, ST839, ST840, ST841, and ST842 were identified, which grouped into two lineages. Phylogenetic analysis suggested that the most two frequent STs in China, ST837 and ST836, may be the derivatives of E. coli O157:H7 Sakai or E. coli O157:H7 EDL933. Geographical diversity and host variety of E. coli O157:H7 were observed in China. In addition, the different distribution of tccp was detected. The data presented herein provide new insights into the molecular epidemiologic feature of E. coli O157:H7, and aid in the investigation of the transmission regularity and evolutionary mechanism of E. coli O157:H7.

Status and Determinants of Health Literacy among Adolescents in Guangdong, China

Ye, Xiao-Hua,Yang, Yi,Gao, Yan-Hui,Chen, Si-Dong,Xu, Ya Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.20

Background: Previous studies for non-communicable disease cotrol, including cancer, have mostly relied on health literacy in adults. However, limited studies are available for adolescents. This study aimed to assess the status and determinants of health literacy in in-school adolescents in Guangdong, China. Materials and Methods: A total of 3,821 students aged 13-25 years were selected by multi-stage cluster sampling. After the questionnaire of health literacy was answered, the total scores for health knowledge (18 questions), skills (5 questions) and behaviors (14 questions) were determined. The total scores for health literacy and each subscale were recoded into adequate and inadequate subgroups, and logistic regression models were used to identify factors associated with each outcome variable. Results: The prevalence of adequate health literacy was 14.4%, and the prevalences for adequate knowledge, skills and behavior were 22.4%, 64.7% and 6.6%, respectively. Students coming from prestigious schools and having parents with higher education had higher odds of having adequate knowledge, skills and behaviors. Female students had higher odds of having adequate knowledge and behaviors. Students in grade 7-8 had higher odds of having adequate knowledge and skills. The health knowledge was positive associated with health skills (odds ratio [OR] =2.1, 95% confidence interval [CI] 1.7-2.5) and behaviors (OR=3.0, 95%CI 2.3-4.0), and health skills were positive associated with health behaviors (OR=2.6, 95%CI 1.8-3.8). Conclusions: Further efforts should be made to increase adolescents' health knowledge and behaviors, especially for low grade and male students in non-prestigious schools.

Prevalence and Subtypes of Blastocystis in Alpacas, Vicugna pacos in Shanxi Province, China

Ye-Ting Ma,Qing Liu,Shi-Chen Xie,Xiao-Dong Li,Yuan-Yuan Ma,Tao-Shan Li,Wen-Wei Gao,Xing-Quan Zhu 대한기생충학ㆍ열대의학회 2020 The Korean Journal of Parasitology Vol.58 No.2

Blastocystis, an enteric protist, has been reported to be an important cause of protozoal gastrointestinal manifestations in humans and animals worldwide. Animals harboring certain Blastocystis subtypes (STs) may serve as a potential source of human infection. However, information about the prevalence and genetic diversity of Blastocystis in alpacas is limited. In the present study, a total of 366 fecal samples from alpacas in Shanxi Province, northern China, were examined for Blastocystis by PCR amplification of the small subunit rRNA gene, followed by sequencing and phylogenetic analysis. The prevalence of Blastocystis in alpacas was 23.8%, and gender difference in the prevalence of Blastocystis was observed. The most predominant Blastocystis ST was ST10, followed by ST14 and ST5. The detection of ST5, a potentially zoonotic genotype, indicates that alpacas harboring ST5 could be a potential source of human infection with Blastocystis. These data provide new insight into the prevalence and genetic diversity of Blastocystis in alpacas.

Comparison of Gadobenate Dimeglumine and Gadopentetate Dimeglumine for Breast MRI Screening: a Meta-analysis

Yang, Xiao-Ping,Han, Yue-Dong,Ye, Jian-Jun,Chen, Gang,Luo, Ying,Ma, Hong-Xia,Yu, Xue-Wen,Niu, Juan-Qin,Ren, Fang-Yuan,Guo, You-Ming Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.12

Background: As a common and essential contrast medium at present, gadobenate dimeglumine has shown better performance than some other agents when applied to Breast Magnetic Resonance Imaging Screening (Breast MRI Screening). Nevertheless, reports on the diagnostic performance of these two mediums (gadobenate dimeglumine and gadopentetate dimeglumine) are not completely consistent. Objective: To assess the diagnostic value of gadobenate dimeglumine and gadopentetate dimeglumine for Breast MRI Screening in patients suffering from breast cancer and to provide more convinced evidence to guide clinical practice in terms of appropriate contrast agents. Data Sources and Review Methods: Original articles in English and Chinese published before January 2013 were selected from available databases (The Cochrane Library, PUBMED, EMBASE, Chinese Biomedical Literature Database, Chinese Scientific Journals Full-text Database, Chinese Journal Full-text). The criteria for inclusion and exclusion were based on the standard for diagnosis tests. Meta-Disc software (Version 1.4) was used for data analysis. Then, the area under curve (AUC) of SROC and the spearman rank correlation of sensitivity against (1-specificity) were calculated. Results: Total of 17 researches involving 1934 patients were included. The pooled sensitivity of gadobenate dimeglumine and gadopentetate dimeglumine were 0.99 (0.97, 1.00) and 0.93 (0.88, 1.00) respectively. The pooled specificity for these two contrast agents were 0.924 (0.902, 0.943) and 0.838 (0.817, 0.858) respectively, and the AUC of SROC curve were 0.9781 and 0.9215 respectively. Conclusions: Gadobenate dimeglumine can be regarded as a more effective and feasible contrast medium for Breast MRI Screening. At least 5% differences in diagnostic performance are usually considered as clinically relevant.

Ultra-sensitive graphene based mid-infrared plasmonic bio-chemical sensing using dielectric beads as a medium

Liu, Xiao,Zhang, Duan,Wu, Ye-Cun,Yang, Mei,Wang, Qian,Coileá,in, Cormac Ó,.,Xu, Hongjun,Yang, Chen,Abid, Mohamed,Abid, Mourad,Liu, Huajun,Chun, Byong Sun,Shi, Qingfan,Wu, Han-Chun Elsevier 2017 Carbon Vol.122 No.-

<P>Graphene is moving beyond the realm of simple electronic devices toward areas such as advanced biochemical sensing. The infrared (IR) response of graphene, characterized by collective long-lived charge-carrier oscillations, could be applied in IR-absorption spectroscopy, typically used for bio-chemical analysis. However, direct light absorption by propagating plasmons in graphene is forbidden due to the large momentum mismatch. Proposed methods to overcome this bottleneck come at a cost, the use of noble metal particles on graphene reduces the spectral bandwidth and nano-structuring graphene is expensive. Here, we propose a simple and cheap method to fabricate large scale ultra-sensitive graphene based mid-IR biosensors, by introducing dielectric beads to excite mid-IR range plasmons. Interference from waves scattered by the beads excite surface plasmon polaritons, which propagate several micrometers in graphene and enhance the interaction between the molecules and mid-IR light. This method opens an interesting window for the application of graphene in bio-chemical sensing. (C) 2017 Elsevier Ltd. All rights reserved.</P>

Association Between the c.3751G>A Genetic Variant of MDR1 and Hepatocellular Carcinoma Risk in a Chinese Han Population

Li, Xiao-Fei,He, Hua-Bin,Zhu, Yan-Shuang,He, Jin-Ke,Ye, Wei-Wei,Chen, Yong-Xin,Lou, Lian-Qing Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.9

The objective of this study was to evaluate the influence of a genetic variant in the multidrug resistance 1 gene (MDR1) on hepatocellular carcinoma (HCC) risk. This case-control study was conducted in a Chinese population of 645 HCC cases and 658 cancer-free controls. The genotype of the c.3751G>A genetic variant in the MDR1 gene was investigated by created restriction site-polymerase chain reaction (CRS-PCR) and DNA sequencing methods. Our data demonstrated significantly differences detected in the allelic and genotypic frequencies between HCC cases and those of cancer-free controls. Association analyses indicated that there were statistically increased risk of HCC in the homozygote comparison (AA versus (vs.) GG: OR=2.22, 95% CI 1.51-3.27, ${\chi}^2$=16.90, P<0.001), dominant model (AA/GA vs. GG: OR=1.25, 95% CI 1.00-1.55, ${\chi}^2$=3.98, P=0.046), recessive model (AA vs. GA/GG: OR=2.14, 95% CI 1.47-3.09, ${\chi}^2$=16.68, P<0.001) and allele comparison (A vs. G: OR=1.33, 95% CI 1.13-1.57, ${\chi}^2$=11.66, P=0.001). The allele-A and genotype-AA may contribute to HCC susceptibility. These preliminary findings suggest that the c.3751G>A genetic variant in the MDR1 gene is potentially related to HCC susceptibility in a Chinese Han population, and might be used as a molecular marker for evaluating HCC susceptibility.