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Sereti V Stamatis H Pappas C Polissiou M Kolisis F 《Biotechnology and bioengineering》2001,72(4):495-500
Esters were prepared by acylation of hydroxypropyl cellulose with fatty acid catalyzed by immobilized lipase from Candida antarctica in tert-butanol. The nature of the substrates used, the initial water activity of the system, and the molecular weight of the hydroxypropyl cellulose were investigated. Moreover, Fourier transform-infrared (FT-IR) spectroscopy was used for determination of ester content on hydroxypropyl cellulose. Specifically, a linear relationship was established between the peak height assigned to the absorption of the esterified carboxyl groups of the cellulose and the ester content. At optimum reaction conditions, the ester content on the hydroxypropyl cellulose was about 11%. 相似文献
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Athanasios C. Kimbaris Antonios Michaelakis Angeliki F. Martinou Moschos G. Polissiou 《Biocontrol Science and Technology》2010,20(4):411-422
The comparative toxicity of five essential oil vapours was tested against four aphid species, the black bean aphid Aphis fabae, the pea aphid Acyrthosiphon pisum, the chrysanthemum aphid Macrosiphoniella sanborni, the green peach aphid Myzus persicae and on two of the most common coccinellid predators, the seven-spotted ladybird Coccinella septempunctata and the two-spotted ladybird Adalia bipunctata. All essential oils were highly toxic to the aphid species tested with LC50 and LC99 values ranging between 0.17 and 1.92 and 0.44 and 4.83 µL/L air, respectively, depending on the aphid species and on the essential oil. Coccinellid predators were also highly susceptible to the essential oil vapours and the selective toxicity ratio varied depending on aphid species, coccinellid predator and essential oil. The possibilities for the utililization of essential oils as aphicides, especially in IPM programmes in glasshouses are discussed with regard to the present findings. 相似文献
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Leptin in immunology 总被引:16,自引:0,他引:16
Matarese G Moschos S Mantzoros CS 《Journal of immunology (Baltimore, Md. : 1950)》2005,174(6):3137-3142
Leptin is an adipokine which conveys information on energy availability. In humans, leptin influences energy homeostasis and regulates neuroendocrine function primarily in states of energy deficiency. As a cytokine, leptin also affects thymic homeostasis and, similar to other proinflammatory cytokines, leptin promotes Th1 cell differentiation and cytokine production. We review herein recent advances on the role of leptin in the pathophysiology of immune responses. 相似文献
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DNA damage repair is an important cell function for genome integrity and its deregulation can lead to genomic instability and development of malignancies. Sumoylation is an increasingly important ubiquitin-like modification of proteins affecting protein stability, enzymatic activity, nucleocytoplasmic trafficking, and protein-protein interactions. In particular, several important DNA repair enzymes are subject to sumoylation, which appears to play a role in copping with DNA damage insults. Recent reports indicate that Ubc9, the single SUMO E2 enzyme catalyzing the conjugation of SUMO to target proteins, is overexpressed in certain tumors, such as lung adenocarcinoma, ovarian carcinoma and melanoma, suggestive of its clinic significance. This review summarizes the most important DNA damage repair pathways which are potentially affected by Ubc9/SUMO and their role in regulating the function of several proteins involved in the DNA damage repair machinery. 相似文献
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Chenxi Gao Guangming Chen Guillermo Romero Stergios Moschos Xiang Xu Jing Hu 《The Journal of biological chemistry》2014,289(10):7099-7108
A pivotal step in canonical Wnt signaling is Wnt-induced β-catenin stabilization. In the absence of Wnt, β-catenin is targeted for β-transducin repeats-containing proteins (β-TrCP)-mediated degradation due to phosphorylation by glycogen synthase kinase 3 (Gsk3). How canonical Wnt signaling regulates Gsk3 to inhibit β-catenin proteolysis remains largely elusive. This study reveals novel key molecular events in Wnt signaling: induction of Gsk3β ubiquitination and Gsk3β-β-TrCP binding. We found that Wnt stimulation induced prolonged monoubiquitination of Gsk3β and Gsk3β-β-TrCP interaction. Monoubiquitination did not cause Gsk3β degradation nor affects its enzymatic activity. Rather, increased monoubiquitination of Gsk3β/Gsk3β-β-TrCP association suppressed β-catenin recruitment of β-TrCP, leading to long-term inhibition of β-catenin ubiquitination and degradation. 相似文献
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Using surface-enhanced infrared absorption (SEIRA) spectroscopy of dry films of colloidal gold (CG) bioconjugates with protein A, it is shown that certain characteristic bands of the protein (e.g., amide I, amide II and some other vibration modes) are essentially affected by the metal surface. Thus, the method may be used for controlling the quality of such bioconjugates. Moreover, it is demonstrated that the biospecific reaction of protein A attached to CG particles with human immunoglobulin G (IgG) results in further essential changes in SEIRA spectra, providing a means for an easy and rapid IR spectroscopic detection of biospecific immunochemical interactions (i.e., spectroimmunochemistry). The results obtained can form a basis for developing test systems for detecting various biospecific interactions. 相似文献
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Biocidal Compounds from Mentha sp. Essential Oils and Their Structure–Activity Relationships 下载免费PDF全文
Athanasios C. Kimbaris Azucena González‐Coloma Maria Fe Andrés Veroniki P. Vidali Moschos G. Polissiou Omar Santana‐Méridas 《化学与生物多样性》2017,14(3)
Essential oils from Greek Mentha species showed different chemical compositions for two populations of M. pulegium, characterized by piperitone and pulegone. Mentha spicata essential oil was characterized by endocyclic piperitenone epoxide, piperitone epoxide, and carvone. The bioactivities of these essential oils and their components have been tested against insect pests (Leptinotarsa decemlineata, Spodoptera littoralis and Myzus persicae), root‐knot nematodes (Meloydogine javanica) and plants (Lactuca sativa, Lolium perenne, Solanum lycopersicum). The structure–activity relationships of these compounds have been studied including semi‐synthetic endocyclic trans‐carvone epoxide, exocyclic carvone epoxide, a new exocyclic piperitenone epoxide and trans‐pulegone epoxide. Leptinotarsa decemlineata feeding was affected by piperitenone and piperitone epoxide. Spodoptera littoralis was affected by piperitone epoxide and pulegone. The strongest nematicidal agent was piperitenone epoxide, followed by piperitone epoxide, piperitenone and carvone. Germination of S. lycopersicum and L. perenne was significantly affected by piperitenone epoxide. This compound and carvone epoxide inhibited L. perenne root and leaf growth. Piperitenone epoxide also inhibited the root growth of S. lycopersicum. The presence of a C(1) epoxide resulted in strong antifeedant, nematicidal and phytotoxic compounds regardless of the C(4) substituent. New natural crop protectants could be developed through appropriate structural modifications in the p‐menthane skeleton. 相似文献
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Modern peptide and protein subunit vaccines suffer from poor immunogenicity and require the use of adjuvants. However, none of the currently licensed adjuvants can elicit cell-mediated immunity or are suitable for mucosal immunization. In this study we explored the immunological effect of nasal co-administration of adjuvants with distinct functions: cholera toxin subunit B, a potent mucosal adjuvant that induces strong humoral responses, muramy di-peptide (MDP), an adjuvant known to elicit cell mediated immunity but rarely used nasally, and chitosan, an adjuvant that achieves specific physiological effects on mucosal membranes that improve antigen uptake. Groups of five female BALB/c mice received on days 1 and 56 nasal instillations of the recombinant Helicobacter pylori antigen urease admixed to single or multiple adjuvant combinations. Serum IgG kinetics were followed over 24 weeks. At the conclusion of the experiment, local antibody responses were determined and antigen-specific recall responses in splenocyte cultures were assayed for proliferation and cytokine production. The combination of adjuvants was shown to further contribute to the increased antigenicity of recombinant H. pylori urease. The data presented here outline and support facilitation of increased immunomodulation by an adjuvant previously defined as an effective mucosal adjuvant (chitosan) for another adjuvant (MDP) that is not normally effective via this route. 相似文献
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William R. Jeck Joel Parker Craig C. Carson Janiel M. Shields Maria J. Sambade Eldon C. Peters Christin E. Burd Nancy E. Thomas Derek Y. Chiang Wenjin Liu David A. Eberhard David Ollila Juneko Grilley‐Olson Stergios Moschos D. Neil Hayes Norman E. Sharpless 《Pigment cell & melanoma research》2014,27(4):653-663
Somatic sequencing of cancers has produced new insight into tumorigenesis, tumor heterogeneity, and disease progression, but the vast majority of genetic events identified are of indeterminate clinical significance. Here, we describe a NextGen sequencing approach to fully analyzing 248 genes, including all those of known clinical significance in melanoma. This strategy features solution capture of DNA followed by multiplexed, high‐throughput sequencing and was evaluated in 31 melanoma cell lines and 18 tumor tissues from patients with metastatic melanoma. Mutations in melanoma cell lines correlated with their sensitivity to corresponding small molecule inhibitors, confirming, for example, lapatinib sensitivity in ERBB4 mutant lines and identifying a novel activating mutation of BRAF. The latter event would not have been identified by clinical sequencing and was associated with responsiveness to a BRAF kinase inhibitor. This approach identified focal copy number changes of PTEN not found by standard methods, such as comparative genomic hybridization (CGH). Actionable mutations were found in 89% of the tumor tissues analyzed, 56% of which would not be identified by standard‐of‐care approaches. This work shows that targeted sequencing is an attractive approach for clinical use in melanoma. 相似文献