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951.
Jiong Wang Liyong Gan Qianwen Zhang Vikas Reddu Yuecheng Peng Zhichao Liu Xinghua Xia Cheng Wang Xin Wang 《Liver Transplantation》2019,9(3)
A structurally simple molecular 1,10‐phenanthroline‐Cu complex on a mesostructured graphene matrix that can be active and selective toward CO2 reduction over H2 evolution in an aqueous solution is reported. The active sites consist of Cu(I) center in a distorted trigonal bipyramidal geometry, which enables the adsorption of CO2 with η1‐COO‐like configuration to commence the catalysis, with a turnover frequency of ≈45 s?1 at ?1 V versus reversible hydrogen electrode. Using in situ infrared spectroelectrochemical investigation, it is demonstrated that the Cu complex can be reversibly heterogenized near the graphene surface via potential control. An increase of electron density in the complex is observed as a result of the interaction from the electric field, which further tunes the electron distribution in the neighboring CO2. It is also found that the mesostructure of graphene matrix favored CO2 reduction on the Cu center over hydrogen evolution by limiting mass transport from the bulk solution to the electrode surface. 相似文献
952.
Caihong Yu Dong Ai Ronghua Lin Shenhang Cheng 《Archives of insect biochemistry and physiology》2019,100(4)
The purpose of this study was to evaluate the effects of three toxic β‐glucosides, phlorizin, santonin, and amygdalin, on carbohydrate metabolism in the cotton bollworm, Helicoverpa armigera (Hübner), when diets mixed with β‐glucosides were fed to third‐instar larvae. The growth of the larvae was significantly inhibited by exposure to santonin after 96 hr but not obviously affected by phlorizin and amygdalin. The midgut trehalase activities were only 51.7%, 32%, and 42.5% of that of the control after treatment with phlorizin, santonin and amygdalin at 2 mg/ml, respectively. In the hemolymph and fat body, the amount of trehalose decreased in all cases. However, the effects of santonin on the alteration of the glycogen and glucose levels as well as the activities of glycogen phosphorylase, were different than those of the other two β‐glucosides. It appears that the three β‐glucosides have different influences on the carbohydrate metabolism of cotton bollworm. 相似文献
953.
目的利用人源抗狂犬病病毒ScFv噬菌体抗体库,构建单克隆抗体(单抗)轻、重链质粒,瞬时表达,纯化后验证具有高中和活性的单抗。方法以从ScFv噬菌体抗体库中筛选获得特异性抗体为模板,PCR扩增抗体轻、重链可变区序列,构建人源全分子抗体瞬时转染质粒;轻、重链质粒混合后转染HEK293 EBNA1细胞,瞬时表达全分子抗体。采用Mabselect SuRe介质手动亲和纯化抗体,Nano Vue超微量分光光度计测定蛋白质的质量浓度,快速荧光灶抑制试验(rapid fluorescent focus inhibition test, RFFIT)进行体外中和效价验证。结果成功构建22个轻链质粒,15个重链质粒。通过真核细胞瞬时表达后,经手动亲和纯化后,获得22株单抗。除1株抗体外,其余21株抗体的蛋白质量浓度均>300μg/mL;部分抗体纯度均在90%以上。中和活性结果显示,5株在1 500~1 800 IU/mg之间;8株在800~1 500 IU/mg之间;7株在500~800 IU/mg之间;其余2株在500 IU/mg以下。结论成功构建并验证获得20株中和活性>500 IU/mg的人源抗狂犬病病毒单抗,为单抗混合制剂的研究奠定了基础。 相似文献
954.
Yufei Wang Bang Wang Haihua Xie Qianwen Ren Xiexie Liu Fanfan Li Xiujuan Lv Xiubin He Congsheng Cheng Ruzhi Deng Jin Li Junzhao Zhao Zongming Song Feng Gu 《Biotechnology journal》2019,14(7)
Genome editing using RNA‐guided nucleases in their ribonucleoprotein (RNP) form represents a promising strategy for gene modification and therapy because they are free of exogenous DNA integration and have reduced toxicity in vivo and ex vivo. However, genome editing by Cas9 nuclease from Staphylococcus aureus (SaCas9) has not been reported in its RNP form, which recognizes a longer protospacer adjacent motif (PAM), 5′‐NNGRRT‐3′, compared with Streptococcus pyogenes Cas9 (SpCas9) of 5′‐NGG‐3′ PAM. Here, SaCas9‐RNP‐mediated genome editing is reported in human cells. The SaCas9‐RNP displayed efficient genome editing activities of enhanced green fluorescent protein (EGFP) coding gene as well as three endogenous genes (OPA1, RS1, and VEGFA). Further, SaCas9‐RNP is successfully implemented to correct a pathogenic RS1 mutation for X‐linked juvenile retinoschisis. It is also shown that off‐target effects triggered by SaCas9‐RNP are undetectable by targeted deep sequencing. Collectively, this study demonstrates the potential of SaCas9‐RNP‐mediated genome editing in human cells, which could facilitate genome‐editing‐based therapy. 相似文献
955.
Huilin Su Li Li Benlin Cheng Junhao Zhu Qiangqiang Zhang Jinhua Xu Min Zhu 《Mycopathologia》2017,182(5-6):549-554
Infections caused by Trichophyton rubrum are very common in dermatological disease. It most often appears as superficial cutaneous mycosis, such as tinea manuum, tinea pedis, and tinea corporis. However, deep infection caused by T. rubrum was rarely reported. We describe a case of mixed type of deep infection caused by T. rubrum in a 45-year-old man with no significant immunodeficiency. This patient had a history of onychomycosis on the toenails without regular treatment for nearly 6 years. And, he had erythema, papule, and nodules on the submandibular area, neck, and chest for almost 1 year. After treated with intravenous infusion of cefotiam for 2 weeks, the lesion aggravated. The fungal direct microscopic examination of pyogenic fluid was positive, and the fungal cultures that produced reddish-brown and yellow pigment showed cottony, wooly, and white colony. After the DNA sequencing, it was identified as T. rubrum. We gave the patient oral terbinafine 250 mg per day and bifonazole cream for external use. Six months later, the patient’s skin lesion was disappeared, and healthy nail growth was seen in two-thirds of nail bed. The terbinafine is effective against deep infection caused by T. rubrum. 相似文献
956.
Sophie S.W. Wang Ching‐Min Huang Yi‐Wei Lee Michael Isaac Chen Szu‐An Chuang Shu‐Hua Chen Ying‐Wei Lu Chun‐Cheng Lin Ka‐Wo Lee Wen‐Hung Hsu Kun‐Pin Wu Yu‐Ju Chen 《Proteomics》2017,17(11)
We reported an integrated platform to explore serum protein variant pattern in cancer and its utility as a new class of biomarker panel for diagnosis. On the model study of serum amyloid A (SAA), we employed nanoprobe‐based affinity mass spectrometry for enrichment, identification and quantitation of SAA variants from serum of 105 gastric cancer patients in comparison with 54 gastritis patients, 54 controls, and 120 patients from other cancer. The result revealed surprisingly heterogeneous and most comprehensive SAA bar code to date, which comprises 24 SAA variants including SAA1‐ and SAA2‐encoded products, polymorphic isoforms, N‐terminal–truncated forms, and three novel SAA oxidized isotypes, in which the variant‐specific peptide sequence were also confirmed by LC‐MS/MS. A diagnostic model was developed for dimension reduction and computational classification of the 24 SAA‐variant bar code, providing good discrimination (AUC = 0.85 ± 3.2E?3) for differentiating gastric cancer group from gastritis and normal groups (sensitivity, 0.76; specificity, 0.81) and was validated with external validation cohort (sensitivity, 0.71; specificity, 0.74). Our platform not only shed light on the occurrence and modification extent of under‐represented serum protein variants in cancer, but also suggested a new concept of diagnostic platform by serum protein variant profile. 相似文献
957.
Effects of soil heterogeneity and clonal integration on Alternanthera philoxeroides populations with a radial ramet aggregation 下载免费PDF全文
Some clonal plants can spread their ramet populations radially, and soil heterogeneity and clonal integration may greatly affect the establishment of these types of populations. We constructed Alternanthera philoxeroides populations with a radial ramet aggregation, allowing old ramets of clonal fragments to concentrate in central pots and younger ramets to root in peripheral pots. The peripheral pots were supplemented either with three different levels (high, medium and low) of soil nutrients to simulate a heterogeneous soil environment, or only one medium level of soil nutrients to simulate a homogeneous environment. Stolon connections between the central older ramets and the peripheral younger ramets were left intact or severed to test the effect of clonal integration. The maintenance of stolon connection could induce the division of labor between different‐aged ramets, by increasing the root investment in central ramets and the above‐ground growth in peripheral ramets. The maintenance of stolon connection could improve the growth of the central and peripheral ramets, clonal fragments and even the whole population. However, the positive consequence in peripheral ramets and whole fragments was only detected in the high‐nutrient patch of heterogeneous treatment. In sum, in the population with the radial ramet aggregation, clonal integration can play a key role in the rapid recruitment of young ramets of A. philoxeroides fragments, as well as the expansion of the whole population. The magnitude of clonal integration also became more obvious in the peripheral young ramets and whole fragments that experienced high‐nutrient patches. 相似文献
958.
A proteomics approach to identifying novel protein targets involved in erinacine A–mediated inhibition of colorectal cancer cells’ aggressiveness 下载免费PDF全文
Ko‐Chao Lee Hsing‐Chun Kuo Chien‐Heng Shen Chien‐Chang Lu Wen‐Shih Huang Meng‐Chiao Hsieh Cheng‐Yi Huang Yi‐Hung Kuo Yung‐Yu Hsieh Chih‐Chuan Teng Li‐Ya Lee Shui‐Yi Tung 《Journal of cellular and molecular medicine》2017,21(3):588-599
Erinacine A, a major active component of a diterpenoid derivative isolated from Hericium erinaceus mycelium, has been demonstrated to exert anticancer effects. Herein, we present an investigation of the molecular mechanism of erinacine A induction associated with cancer cells’ aggressive status and death. A proteomic approach was used to purify and identify the differentially expressed proteins following erinacine A treatment and the mechanism of its action in apoptotic and the targets of erinacine A. Our results demonstrate that erinacine A treatment of HCT‐116 and DLD‐1 cells increased cell cytotoxicity and reactive oxygen species (ROS) production as well as decreased cell proliferation and invasiveness. Ten differentially displayed proteins were determined and validated in vitro and in vivo between the erinacine A‐treated and untreated groups. In addition, erinacine A time‐dependent induction of cell death and inhibitory invasiveness was associated with sustained phosphorylation of the PI3K/mTOR/p70S6K and ROCK1/LIMK2/Cofilin pathways. Furthermore, we demonstrated that erinacine A–induced HCT‐116 and DLD‐1 cells viability and anti‐invasion properties by up‐regulating the activation of PI3K/mTOR/p70S6K and production of ROS. Experiments involving specific inhibitors demonstrated that the differential expression of cofilin‐1 (COFL1) and profilin‐1 (PROF1) during erinacine A treatment could be involved in the mechanisms of HCT‐116 and DLD‐1 cells death and decreased aggressiveness, which occurred via ROCK1/LIMK2/Cofilin expression, with activation of the PI3K/mTOR/p70S6K signalling pathway. These findings elucidate the mechanism of erinacine A inhibiting the aggressive status of cells by activating PI3K/mTOR/p70S6K downstream signalling and the novel protein targets COF1 and PROF1; this could be a good molecular strategy to limit the aggressiveness of CRC cells. 相似文献
959.
Kathleen Woodruff Teresa Defrancesco Sandra Tou Christina M. Williams Mathew Breen Kathryn Meurs Bruce Keene Ke Cheng 《Journal of cellular and molecular medicine》2017,21(8):1503-1512
Cardiosphere‐derived cells (CDCs) have been shown to reduce scar size and increase viable myocardium in human patients with mild/moderate myocardial infarction. Studies in rodent models suggest that CDC therapy may confer therapeutic benefits in patients with non‐ischaemic dilated cardiomyopathy (DCM). We sought to determine the safety and efficacy of allogeneic CDC in a large animal (canine) model of spontaneous DCM. Canine CDCs (cCDCs) were grown from a donor dog heart. Similar to human CDCs, cCDCs express CD105 and are slightly positive for c‐kit and CD90. Thirty million of allogeneic cCDCs was infused into the coronary vessels of Doberman pinscher dogs with spontaneous DCM. Adverse events were closely monitored, and cardiac functions were measured by echocardiography. No adverse events occurred during and after cell infusion. Histology on dog hearts (after natural death) revealed no sign of immune rejection from the transplanted cells. 相似文献
960.
P2X7 receptor inhibition attenuated sympathetic nerve sprouting after myocardial infarction via the NLRP3/IL‐1β pathway 下载免费PDF全文
Hesheng Hu Xiaolu Li Mei Xue Wenjuan Cheng Ye Wang Xinran Li Na Yang Yugen Shi Suhua Yan 《Journal of cellular and molecular medicine》2017,21(11):2695-2710
Mounting evidence supports the hypothesis that inflammation modulates sympathetic sprouting after myocardial infarction (MI). The myeloid P2X7 signal has been shown to activate the nucleotide‐binding and oligomerization domain‐like receptor family pyrin domain‐containing 3 (NLRP3) inflammasome, a master regulator of inflammation. We investigated whether P2X7 signal participated in the pathogenesis of sympathetic reinnervation after MI, and whether NLRP3/interleukin‐1β (IL‐1β) axis is involved in the process. We explored the relationship between P2X7 receptor (P2X7R) and IL‐1β in the heart tissue of lipopolysaccharide (LPS)‐primed naive rats. 3′‐O‐(4‐benzoyl) benzoyl adenosine 5′‐triphosphate (BzATP), a P2X7R agonist, induced caspase‐1 activation and mature IL‐1β release, which was further neutralized by a NLRP3 inhibitor (16673‐34‐0). MI was induced by coronary artery ligation. Following infarction, a marked increase in P2X7R was localized within infiltrated macrophages and observed in parallel with an up‐regulation of NLRP3 inflammasome levels and the release of IL‐1β in the left ventricle. The administration of A‐740003 (a P2X7R antagonist) significantly prevented the NLRP3/IL‐1β increase. A‐740003 and/or Anakinra (an IL‐1 receptor antagonist) significantly reduced macrophage infiltration as well as macrophage‐based IL‐1β and NGF (nerve growth factor) production and eventually blunted sympathetic hyperinnervation, as assessed by the immunofluorescence of tyrosine hydroxylase (TH) and growth‐associated protein 43 (GAP 43). Moreover, the use of Anakinra partly attenuated sympathetic sprouting. This indicated that the effect of P2X7 on neural remodelling was mediated at least partially by IL‐1β. The arrhythmia score of programmed electric stimulation was in accordance with the degree of sympathetic hyperinnervation. In vitro studies showed that BzATP up‐regulated secretion of nerve growth factor (NGF) in M1 macrophages via IL‐1β. Together, these data indicate that P2X7R contributes to neural and cardiac remodelling, at least partly mediated by NLRP3/IL‐1β axis. Therapeutic interventions targeting P2X7 signal may be a novel approach to ameliorate arrhythmia following MI. 相似文献