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41.
42.
Pengfei Li Liming Ruan Ruofan Wang Tianqi Liu Gao Song Xiaofei Gao Guohua Jiang Xiaoyan Liu 《仿生工程学报(英文版)》2021,18(6):1378-1390
Nanofibers(NFs)have been widely used in tissue engineering such as wound healing.In this work,the antibacterial ZnO quantum dots(ZnO QDs)have been incorporated into the biocompatible poly(ε-caprolactone)/collagen(PCL/Col)fibrous scaffolds for wound healing.The as-fabricated PCL-Col/ZnO fibrous scaffolds exhibited good swelling,antibacterial activity,and biodegradation behaviors,which were beneficial for the applications as a wound dressing.Moreover,the PCL-Col/ZnO fibrous scaffolds showed excellent cytocompatibility for promoting cell proliferation.The resultant PCL-Col/ZnO fibrous scaffolds containing vascular endothelial growth factor(VEGF)also exhibited promoted wound-healing effect through promoting expression of transforming growth factor-β(TGF-β)and the vascular factor(CD31)in tissues in the early stages of wound healing.This new electrospun fibrous scaffolds with wound-healing promotion and antibacterial property should be convenient for treating wound healing. 相似文献
43.
Characterization of ammonium and nitrate uptake and assimilation in roots of tea plants 总被引:3,自引:0,他引:3
Y. Y. Yang X. H. Li R. G. Ratcliffe J. Y. Ruan 《Russian Journal of Plant Physiology》2013,60(1):91-99
It has been pointed out that tea (Camellia sinensis (L.) O. Kuntze) prefers ammonium (NH 4 + ) over nitrate (NO 3 ? ) as an inorganic nitrogen (N) source. 15N studies were conducted using hydroponically grown tea plants to clarify the characteristics of uptake and assimilation of NH 4 + and NO 3 ? by tea roots. The total 15N was detected, and kinetic parameters were calculated after feeding 15NH 4 + or 15NO 3 ? to tea plants. The process of N assimilation was studied by monitoring the dynamic 15N abundance in the free amino acids of tea plant roots by GC-MS. Tea plants supplied with 15NH 4 + absorbed significantly more 15N than those supplied with 15NO 3 ? . The kinetics of 15NH 4 + and 15NO 3 ? influx into tea plants followed a classic biphasic pattern, demonstrating the action of a high affinity transport system (HATS) and a low affinity transport system (LATS). The V max value for NH 4 + uptake was 54.5 nmol/(g dry wt min), which was higher than that observed for NO 3 ? (39.3 nmol/(g dry wt min)). KM estimates were approximately 0.06 mM for NH 4 + and 0.16 mM for NO 3 ? , indicating a higher rate of NH 4 + absorption by tea plant roots. Tea plants fed with 15NH 4 + accumulated larger amounts of assimilated N, especially glutamine (Gln), compared with those fed with 15NO 3 ? . Gln, Glu, theanine (Thea), Ser, and Asp were the main free amino acids that were labeled with 15N under both conditions. The rate of N assimilation into Thea in the roots of NO 3 ? -supplied tea plants was quicker than in NH 4 + -supplied tea plants. NO 3 ? uptake by roots, rather than reduction or transport within the plant, seems to be the main factor limiting the growth of tea plants supplied with NO 3 ? as the sole N source. The NH 4 + absorbed by tea plants directly, as well as that produced by NO 3 ? reduction, was assimilated through the glutamine synthetase-glutamine oxoglutarate aminotransferase pathway in tea plant roots. The 15N labeling experiments showed that there was no direct relationship between the Thea synthesis and the preference of tea plants for NH 4 + . 相似文献
44.
Yi-Ming Zhang Jing Ruan Rong Xiao Qiong Zhang Yue-Sheng Huang 《Cell biochemistry and biophysics》2013,67(3):1005-1014
Infrared lasers are widely used in medicine, industry, and other fields. While science, medicine, and the society in general have benefited from the many practical uses of lasers, they also have inherent safety issues. Although several procedures have been put forward to protect the skin from non-specific laser-induced damage, individuals receiving laser therapy or researchers who use laser are still at risk for skin damage. This study aims to understand the interaction between laser and the skin, and to investigate the differences between the skin damage caused by 1,064-nm laser and common thermal burns. Skin lesions on Wistar rats were induced by a 1,064-nm CW laser at a maximum output of 40 W and by a copper brass bar attached to an HQ soldering iron. Histological sections of the lesions and the process of wound healing were evaluated. The widths of the epidermal necrosis and dermal denaturalization of each lesion were measured. To observe wound healing, the epithelial gap and wound gap were measured. Masson’s trichrome and picrosirius red staining were also used to assess lesions and wound healing. The thermal damage induced by laser intensified significantly in both horizontal dimension and in vertical depth with increased duration of irradiation. Ten days after wounding, the dermal injuries induced by laser were more severe. Compared with the laser-induced skin damage, the skin burn induced by an HQ soldering iron did not show a similar development or increased in severity with the passage of time. The results of this study showed the pattern of skin damage induced by laser irradiation and a heated brass bar. This study also highlighted the difference between laser irradiation and thermal burn in terms of skin damage and wound healing, and offers insight for further treatment. 相似文献
45.
46.
Effect of the primary host for production of both sexes on the mating interaction in an autoparasitoid species 总被引:2,自引:0,他引:2
Encarsia sophia (Girault and Dodd) is an autoparasitoid in the hymenopteran family Aphelinidae. The females develop as primary parasitoids on whitefly nymphs (primary hosts), whereas the males develop as hyperparasitoids on their own species or on other primary parasitoid species (secondary hosts). The autoparasitoids not only parasitise whiteflies but also kill them with strong host-feeding capacity. In this study, female and male E. sophia were reared on the primary hosts Trialeurodes vaporariorum and Bemisia tabaci ‘Q’, and the host-feeding and parasitism of wasps on both whitefly species were determined for the four possible different mating combinations: (i) E. sophia females reared on B. tabaci (ESF-BT) mated with E. sophia males from B. tabaci (ESM-BT), (ii) E. sophia females reared on T. vaporariorum (ESF-TV) mated with E. sophia males from T. vaporariorum (ESM-TV), (iii) ESF-BT mated with ESM-TV, and (iv) ESF-TV mated with ESM-BT. ESF-TV mated with ESM-TV killed the largest percentage of whitefly nymphs through host feeding. The ESF-TV with larger body size mating with larger ESM-TV killed more whitefly nymphs through host feeding than those mating with smaller ESM-BT. Whether B. tabaci or T. vaporariorum were used as hosts, ESF-TV mated with ESM-TV and ESM-BT and ESF-BT mated with ESM-BT significantly parasitised more whitefly nymphs than ESF-BT mated with ESM-TV. In general, ESF-BT mated with ESM-TV killed significantly fewer whitefly nymphs through parasitism and host feeding than the other three mating combinations on both whitefly species. These results indicated that the performance of autoparasitoids on insect pests was not only dependent on females but was also affected by mating with males from different primary host species. 相似文献
47.
Xiaoyan Guo Guilin Yang Jin Yuan Peng Ruan Mingxia Zhang Xincun Chen Boping Zhou 《PloS one》2013,8(10)
Concurrent infection with hepatitis C virus (HCV) and hepatitis B virus (HBV) was not uncommon in China. To date, information on predictors of response to treatment of dually-infected HCV/HBV is limited. The aim of this study was to evaluated whether determination of the interleukin 28B (IL-28B) polymorphism statuses sufficient to predict treatment response of interferon (IFN)-based therapy in patients chronically infected with both hepatitis B and C viruses. We investigated the role of IL28B variations (rs8099917 and rs12979860) in response to IFN-based treatment and evaluated its association with the risk of the null virological response (NVR) in HCV /HBV dually-infected patients. We found that the overall distributions of the genotypes among the sustained virological response (SVR), NVR groups were significantly different (P<0.001): patients with the rs8099917 TG genotype had an increased risk of NVR (odds ratio [OR] =2.37 95% confidence interval [CI] =1.16–4.83, P =0.017), and those with the GG genotype had a further increased risk of NVR (OR=4.23, 95% CI =1.17-15.3, P=0.027). The rs12979860 allele was also highly associated with treatment failure (CT/TT vs. CC; OR =2.04, 95%CI =1.05-3.97, P =0.037). Moreover, we found that IL28B rs8099917 G variants (TG+GG) interact with HCV genotype 1(G1) to result in higher risk of NVR (P=0.009), and that they are also associated with HBV DNA reactivation (TG+GG vs. TT, P=0.005). Furthermore, multivariate regression analysis show that the rs8099917 G allele was the most important factor significantly associated with a NVR in HCV G1 patients. This study suggest that IL28B genotyping may be a valid pretreatment predictor of which patients are likely to respond to treatment in this group of difficult-to-treat HCV/HBV dually-infected patients. 相似文献
48.
Xiao-Jin Liu Li-Fang Ruan Xiao-Yan Lin Chang-Ming Zhao Chun-Ying Zhong Ming Sun 《Annals of microbiology》2013,63(4):1639-1644
A multi-copy and small plasmid pBMB2062 from Bacillus thuringiensis kurstaki YBT-1520 strain was cloned and characterized and its distribution was analyzed using dot-blot analysis with the ORF1 fragment as a probe. Bacillus species of 84 serotypes were evaluated. The pBMB2062 plasmid was found to be present in commercial B. thuringiensis kurstaki (H3abc) and aizawai (H7) insecticides of various serotypes, and one Bacillus cereus UW85 strain (produced Zwittermicin fungicide and Cry toxin synergist). The sequences of 7 pBMB2062-like plasmids from randomly selected Bacillus species (positive signal in the dot-blot analysis) were highly conserved. Two open reading frames (ORFs), ORF1 and ORF2, were present in this plasmid. ORF1 was found to be necessary for plasmid replication, whereas ORF2 did not play a role in replication or stability. Based on its sequence homology, ORF2 was a putative solitary antitoxin. Furthermore, the copy number of the replicon of pBMB2062 was higher than those of ori1030 and ori44 based on the thermogenic data, and ori2062 could drive the stable replication of a recombinant plasmid (11 kb total size) in B. thuringiensis. 相似文献
49.
Bingbing Wei You Zhou Zhuoqun Xu Jun Ruan Huan Cheng Ming Zhu Qiang Hu Ke Jin Zhiqiang Yan Deqi Zhou Feng Xuan Hongyi Zhou Zhirong Wang Xing Huang Qiang Wang 《PloS one》2013,8(8)
Background
Glutathione S-transferase P1 (GSTP1) is thought to be involved in the detoxification of reactive carcinogen metabolites. Numerous epidemiological studies have evaluated the association of GSTP1 Ile105Val polymorphism with the risk of prostate cancer. However, the results remain inconclusive. To derive a more precise estimation, a meta-analysis was performed.Methodology/Principal Findings
A comprehensive search was conducted to identify the eligible studies. We used odds ratios (ORs) with 95% confidence intervals (CIs) to assess the strength of the relationship. The overall association was not significant (Val/Val vs. Ile/Ile OR = 1.06, 95% CI = 0.90–1.25, P = 0.50; Val/Val vs. Val/Ile+Ile/Ile: OR = 1.07, 95% CI = 0.91–1.25, P = 0.44). In subgroup analyses by ethnicity and prostate cancer grade, the similar results were observed. However, in stratified analysis by clinical stage, we found a significant association with low-stage prostate cancer (Val/Val vs. Ile/Ile: OR = 2.70, 95% CI = 1.73–4.22, P<0.001; Val/Val vs. Val/Ile+Ile/Ile: OR = 2.14, 95% CI = 1.38–3.33, P = 0.001). Moreover, there was no statistically significant evidence of multiplicative interactions neither between the GSTP1 Ile105Val polymorphism and GSTM1, nor between smoking status and GSTP1 on prostate cancer risk.Conclusions
This meta-analysis showed that GSTP1 Ile105Val polymorphism might not be significantly associated with overall prostate cancer risk. Further stratified analyses showed a significant association with low-stage prostate cancer. 相似文献50.