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101.
102.
Yunjuan Gu Chunfang Wang Ying Zheng Xuhong Hou Yifei Mo Weihui Yu Lei Zhang Cheng Hu Hairong Nan Lei Chen Jie Li Yuxiang Liu Zhezhou Huang Ming Han Yuqian Bao Weijian Zhong Weiping Jia 《PloS one》2013,8(1)
Aim
The aim was to investigate the association between human insulin and cancer incidence and mortality in Chinese patients with type 2 diabetes.Methods
We recruited 8,774 insulin-naïve diabetes patients from the Shanghai Diabetes Registry (SDR). The follow-up rate was 85.4%. All subjects were divided into the insulin use cohort (n = 3,639) and the non-insulin use cohort (n = 5,135). The primary outcome was the first diagnosis of any cancer. The secondary outcome was all-cause mortality. Cox proportional hazards model was used to estimate the relative risk (RR) of cancer and mortality.Results
We observed 98 cancer events in the insulin use cohort and 170 in the non-insulin use cohort. Cancer incidence rates were 78.6 and 74.3 per 10,000 patients per year in the insulin users and the non-insulin users, respectively. No significant difference in cancer risk was observed between the two cohorts (adjusted RR = 1.20, 95% CI 0.89–1.62, P = 0.228). Regarding site-specific cancers, only the risk of liver cancer was significantly higher in the insulin users compared to that in the non-insulin users (adjusted RR = 2.84, 95% CI 1.12–7.17, P = 0.028). The risks of overall mortality (adjusted RR = 1.89, 95% CI 1.47–2.43, P<0.0001) and death from cancer (adjusted RR = 2.16, 95% CI 1.39–3.35, P = 0.001) were all significantly higher in the insulin users than in the non-insulin users.Conclusion
There was no excess risk of overall cancer in patients with type 2 diabetes who were treated with human insulin. However, a significantly higher risk of liver cancer was found in these patients. Moreover, insulin users showed higher risks of overall and cancer mortality. Considering that individuals treated with insulin were more likely to be advanced diabetic patients, caution should be used in interpreting these results. 相似文献103.
In this study, we prepared nano-hydroxyapatite/polyamide 66/glass fibre (n-HA/PA66/GF) bioactive bone screws. The microstructure, morphology and coating of the screws were characterised, and the adhesion, proliferation and viability of MC3T3-E1 cells on n-HA/PA66/GF scaffolds were determined using scanning electron microscope, CCK-8 assays and cellular immunofluorescence analysis. The results confirmed that n-HA/PA66/GF scaffolds were biocompatible and had no negative effect on MC3T3-E1 cells in vitro. To investigate the in vivo biocompatibility, internal fixation properties and osteogenesis of the bioactive screws, both n-HA/PA66/GF screws and metallic screws were used to repair intercondylar femur fractures in dogs. General photography, CT examination, micro-CT examination, histological staining and biomechanical assays were performed at 4, 8, 12 and 24 weeks after operation. The n-HA/PA66/GF screws exhibited good biocompatibility, high mechanical strength and extensive osteogenesis in the host bone. Moreover, 24 weeks after implantation, the maximum push-out load of the bioactive screws was greater than that of the metallic screws. As shown by their good cytocompatibility, excellent biomechanical strength and fast formation and ingrowth of new bone, n-HA/PA66/GF screws are thus suitable for orthopaedic clinical applications. 相似文献
104.
Sujin Bao Libin Zhu Qiang Zhuang Lucia Wang Pin-Xian Xu Keiji Itoh Ian R. Holzman Jing Lin 《PloS one》2013,8(3)
One approach to deliver therapeutic agents, especially proteins, to the gastro-intestinal (GI) tract is to use commensal bacteria as a carrier. Genus Lactobacillus is an attractive candidate for use in this approach. However, a system for expressing exogenous proteins at a high level has been lacking in Lactobacillus. Moreover, it will be necessary to introduce the recombinant Lactobacillus into the GI tract, ideally by oral administration. Whether orally administered Lactobacillus can reach and reside in the GI tract has not been explored in neonates. In this study, we have examined these issues in neonatal rats. To achieve a high level of protein expression in Lactobacillus, we tested the impact of three promoters and two backbones on protein expression levels using mRFP1, a red fluorescent protein, as a reporter. We found that a combination of an L-lactate dehydrogenase (ldhL) promoter of Lactobacillus sakei with a backbone from pLEM415 yielded the highest level of reporter expression. When this construct was used to transform Lactobacillus casei, Lactobacillus delbrueckii and Lactobacillus acidophilus, high levels of mRFP1 were detected in all these species and colonies of transformed Lactobacillus appeared pink under visible light. To test whether orally administered Lactobacillus can be retained in the GI tract of neonates, we fed the recombinant Lactobacillus casei to neonatal rats. We found that about 3% of the bacteria were retained in the GI tract of the rats at 24 h after oral feeding with more recombinant Lactobacillus in the stomach and small intestine than in the cecum and colon. No mortality was observed throughout this study with Lactobacillus. In contrast, all neonatal rats died within 24 hours after fed with transformed E. coli. Taken together, our results indicate that Lactobacillus has the potential to be used as a vehicle for the delivery of therapeutic agents to neonates. 相似文献
105.
Yingjie Yu Xuejiao Yang Huaying Wang Fengxue Shi Ying Liu Jushan Liu Linfeng Li Deli Wang Bao Liu 《PloS one》2013,8(2)
Background
Human activity has a profound effect on the global environment and caused frequent occurrence of climatic fluctuations. To survive, plants need to adapt to the changing environmental conditions through altering their morphological and physiological traits. One known mechanism for phenotypic innovation to be achieved is environment-induced rapid yet inheritable epigenetic changes. Therefore, the use of molecular techniques to address the epigenetic mechanisms underpinning stress adaptation in plants is an important and challenging topic in biological research. In this study, we investigated the impact of warming, nitrogen (N) addition, and warming+nitrogen (N) addition stresses on the cytosine methylation status of Leymus chinensis Tzvel. at the population level by using the amplified fragment length polymorphism (AFLP), methylation-sensitive amplified polymorphism (MSAP) and retrotransposon based sequence-specific amplification polymorphism (SSAP) techniques.Methodology/Principal Findings
Our results showed that, although the percentages of cytosine methylation changes in SSAP are significantly higher than those in MSAP, all the treatment groups showed similar alteration patterns of hypermethylation and hypomethylation. It meant that the abiotic stresses have induced the alterations in cytosine methylation patterns, and the levels of cytosine methylation changes around the transposable element are higher than the other genomic regions. In addition, the identification and analysis of differentially methylated loci (DML) indicated that the abiotic stresses have also caused targeted methylation changes at specific loci and these DML might have contributed to the capability of plants in adaptation to the abiotic stresses.Conclusions/Significance
Our results demonstrated that abiotic stresses related to global warming and nitrogen deposition readily evoke alterations of cytosine methylation, and which may provide a molecular basis for rapid adaptation by the affected plant populations to the changed environments. 相似文献106.
[目的]甘肃马先蒿与感染内生真菌的禾草(紫花针茅和麦宾草)建立根寄生关系,有关内生真菌对根寄生危害禾草光合作用调控方面的研究较少。[方法]本研究以紫花针茅和麦宾草带菌(E+)、不带菌(E-)植株为研究对象,研究甘肃马先蒿寄生和未寄生处理对紫花针茅和麦宾草E+、E-植株不同生长阶段光合特性影响的动态变化。[结果]甘肃马先蒿寄生显著降低紫花针茅和麦宾草的净光合速率、蒸腾速率和气孔导度,而胞间二氧化碳浓度和水分利用率却显著增加,这与禾草是否感染内生真菌无关。甘肃马先蒿寄生后E+紫花针茅的净光合速率、气孔导度和蒸腾速率高于E-植株,而麦宾草E+植株的净光合速率、气孔导度和蒸腾速率却低于E-植株;同时,根寄生条件下E+紫花针茅的胞间二氧化碳浓度和水分利用率低于E-植株;而E-麦宾草植株的胞间二氧化碳浓度和水分利用率却低于E+植株。[结论]内生真菌侵染影响甘肃马先蒿根寄生危害禾草的光合作用;甘肃马先蒿和内生真菌同时成为禾草营养消耗库时,内生真菌与禾草的共生关系处于一种互惠共生和相互拮抗的动态变化。 相似文献
107.
Jiashan Sun Xiurong Wang Xuexia Wen Hongmei Bao Lin Shi Qimeng Tao Yongping Jiang Xianying Zeng Xiaolong Xu Guobin Tian Shimin Zheng Hualan Chen 《PloS one》2016,11(3)
Avian influenza virus (AIV) non-structural protein 1 (NS1) is a multifunctional protein. It is present at high levels in infected cells and can be used for AIV detection and diagnosis. In this study, we generated monoclonal antibody (MAb) D7 against AIV NS1 protein by immunization of BALB/c mice with purified recombinant NS1 protein expressed in Escherichia coli. Isotype determination revealed that the MAb was IgG1/κ-type subclass. To identify the epitope of the MAb D7, the NS1 protein was truncated into a total of 225 15-mer peptides with 14 amino acid overlaps, which were spotted for a peptide microarray. The results revealed that the MAb D7 recognized the consensus DAPF motif. Furthermore, the AIV NS1 protein with the DAPF motif deletion was transiently expressed in 293T cells and failed to react with MAb D7. Subsequently, the DAPF motif was synthesized with an elongated GSGS linker at both the C- and N-termini. The MAb D7 reacted with the synthesized peptide both in enzyme-linked immunosorbent assay (ELISA) and dot-blot assays. From these results, we concluded that DAPF motif is the epitope of MAb D7. To our knowledge, this is the first report of a 4-mer epitope on the NS1 protein of AIV that can be recognized by MAb using a peptide microarray, which is able to simplify epitope identification, and that could serve as the basis for immune responses against avian influenza. 相似文献
108.
109.
Characteristic Steroids from the South China Sea Gorgonian Muricella sibogae and Their Cytotoxicities 下载免费PDF全文
Twenty‐four steroid‐based natural products, 9,10‐secosteroids ( 1 – 10 ), 1,4‐dien‐3‐one steroids ( 11 – 19 ), and 4‐en‐3‐one steroids ( 20 – 24 ), containing varying side‐chains, were isolated from the South China Sea gorgonian Muricella sibogae. The structures of one new 9,10‐secosteroid, sibogol D ( 1 ), and two new 1,4‐dien‐3‐one steroids, sibogols E and F ( 11 and 12 ), were elucidated by extensive spectroscopic analyses and by comparison with the literature data. Cytotoxicities for all the isolates were evaluated against four selected tumor cell lines, HL‐60, HCT116, K562, and P388. Compounds 3, 9 , and 13 exhibited potent cytotoxic activities against the HL‐60 cell line, with IC50 values ranging from 1.27 to 10.05 μM , and compound 3 was also cytotoxic against HCT116 with an IC50 value of 5.8 μM . The bioassay results also indicated a potential relationship between structural patterns and activity. The newly presented series of 1,4‐dien‐3‐one and 4‐en‐3‐one types of steroids relating to the unique 9,10‐secosteroids in biogenesis were found in this species for the first time, which is of considerable chemotaxonomic significance. 相似文献
110.
Wei Chen Pengpeng Zhou Yuanmin Zhu Chen Xie Lin Ma Xiaopeng Wang Zhendong Bao Longjiang Yu 《Bioprocess and biosystems engineering》2016,39(2):315-321
Schizochytrium is a marine microalga that requires high concentrations of sea salt for growth, although problems arise with significant amounts of chloride ions in the culture medium, which corrodes the fermenters. In this work, we evaluated that cell growth and docosahexaenoic acid (DHA) production can be improved when using 1 % (w/v) sodium sulfate instead of 2 % (w/v) sea salt in the culture medium for Schizochytrium sp. S056. In practice, the use of sodium sulfate as the sodium salt led to chloride ion levels in the medium that can be completely removed, thus avoiding fermenter corrosion during Schizochytrium sp. S056 growth, reducing cost and increasing DHA production, and simplifying the disposal of fermentation wastewater. Additionally, we demonstrated that the osmolality of growth media did not play a crucial role in the production of DHA. These findings may be significantly important to companies involved in production of PUFAs by marine microbes. 相似文献