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排序方式: 共有901条查询结果,搜索用时 15 毫秒
891.
Ruggeri L Capanni M Urbani E Perruccio K Shlomchik WD Tosti A Posati S Rogaia D Frassoni F Aversa F Martelli MF Velardi A 《Science (New York, N.Y.)》2002,295(5562):2097-2100
T cells that accompany allogeneic hematopoietic grafts for treating leukemia enhance engraftment and mediate the graft-versus-leukemia effect. Unfortunately, alloreactive T cells also cause graft-versus-host disease (GVHD). T cell depletion prevents GVHD but increases the risk of graft rejection and leukemic relapse. In human transplants, we show that donor-versus-recipient natural killer (NK)-cell alloreactivity could eliminate leukemia relapse and graft rejection and protect patients against GVHD. In mice, the pretransplant infusion of alloreactive NK cells obviated the need for high-intensity conditioning and reduced GVHD. NK cell alloreactivity may thus provide a powerful tool for enhancing the efficacy and safety of allogeneic hematopoietic transplantation. 相似文献
892.
Seaweed produces metabolites aiding in the protection against different environmental stresses. These compounds show antiviral, antiprotozoal, antifungal, and antibacterial properties. Macroalgae can be cultured in high volumes and would represent an attractive source of potential compounds useful for unconventional drugs able to control new diseases or multiresistant strains of pathogenic microorganisms. The substances isolated from green, brown and red algae showing potent antimicrobial activity belong to polysaccharides, fatty acids, phlorotannins, pigments, lectins, alkaloids, terpenoids and halogenated compounds. This review presents the major compounds found in macroalga showing antimicrobial activities and their most promising applications. 相似文献
893.
Celene Navarro Roberto Civera Olivia Arjona Crisalejandra Rivera‐Perez Hugo Sergio García Miguel ngel Hurtado‐Oliva Elena Palacios 《Aquaculture Research》2020,51(4):1602-1622
We substituted 10% of fishmeal with scallop (Argopecten ventricosus) or squid (Dosidiscus gigas) by‐product meal in a feed for shrimp (Litopenaeus vannamei) growth assay that lasted 60 days and then shrimps were submitted to handling stress. Shrimp fed the control diet had smaller weight gain and lower recovery after stress. Prostaglandins in gills were affected by diet and stress, with significant differences in shrimp fed the control diet before and after the stress. Hydroperoxides were increased after stress, while isoprostanoids were higher in shrimp fed the control diet. The gene expression of Glutathione peroxidase and Catalase was increased on the stressed shrimp fed the scallop diet, with no differences among diets for Superoxide dismutase or Cyclooxygenase. Arachidonic acid in the phospholipid fraction of muscle was the only fatty acid affected by stress and diet. Cholesterol oxidation products were significantly higher in shrimp fed the scallop diet compared to shrimp fed the control diet before applying the stress. A PCA analysis grouped in one‐factor growth variables, as well as Superoxide dismutase, esterified astaxanthin and isoprostane, while another factor was determined by stress, prostaglandin and hydroperoxide levels in gills. The partial substitution of fishmeal with scallop of squid by‐product meals affected growth and stress differently, indicating shrimp that grew up more were not necessarily more tolerant to handling stress, which can have a strong repercussion in aquaculture, particularly during density control, recording of growth and harvest. 相似文献
894.
Jung Eun Seol Sang Woo Ahn Bomin Seol Hyeong Rok Yun Nammi Park Hyoung Kyu Kim Elena A. Vasileva Natalia P. Mishchenko Sergey A. Fedoreyev Valentin A. Stonik Jin Han 《Marine drugs》2021,19(10)
Echinochrome A (Ech A, 7-ethyl-2,3,5,6,8-pentahydroxy-1,4-naphthoquinone) has been known to exhibit anti-oxidative and anti-inflammatory effects. However, no study has been carried out on the efficacy of Ech A against skin photoaging; this process is largely mediated by oxidative stress. Six-week-old male SKH-1 hairless mice (n = 36) were divided into five groups. Except for a group that were not treated (n = 4), all mice underwent ultraviolet-B (UVB) exposure for 8 weeks while applying phosphate-buffered saline or Ech A through intraperitoneal injection. UVB impaired skin barrier function, showing increased transepidermal water loss and decreased stratum corneum hydration. UVB induced dermal collagen degeneration and mast cell infiltration. Ech A injection was found to significantly lower transepidermal water loss while attenuating tissue inflammatory changes and collagen degeneration compared to the control. Furthermore, Ech A was found to decrease the relative expression of matrix metalloproteinase, tryptase, and chymase. Taken together, these results suggest that Ech A protects against UVB-induced photoaging in both functional and histologic aspects, causing a lowering of collagen degradation and inflammatory cell infiltration. 相似文献
895.
Elena V. Girich Anton B. Rasin Roman S. Popov Ekaterina A. Yurchenko Ekaterina A. Chingizova Phan Thi Hoai Trinh Ngo Thi Duy Ngoc Mikhail V. Pivkin Olesya I. Zhuravleva Anton N. Yurchenko 《Marine drugs》2022,20(1)
Three new tripeptide derivatives asterripeptides A–C (1–3) were isolated from Vietnamese mangrove-derived fungus Aspergillus terreus LM.5.2. Structures of isolated compounds were determined by a combination of NMR and ESIMS techniques. The absolute configurations of all stereocenters were determined using the Murfey’s method. The isolated compounds 1–3 contain a rare fungi cinnamic acid residue. The cytotoxicity of isolated compounds against several cancer cell lines and inhibition ability of sortase A from Staphylococcus aureus of asterripeptides A–C were investigated. 相似文献
896.
Fangbing Liu Elena Sukhacheva Tatjana Erokhina Jörg Schubert 《European journal of plant pathology / European Foundation for Plant Pathology》1999,105(4):389-395
Potyviral nuclear inclusion b protein (NIb), the RNA-dependent RNA polymerase, contains three highly conserved regions. Peptides corresponding to these regions were synthesised and used for immunisation. A panel of monoclonal antibodies was obtained. Most of the MAbs reacted with the peptides and a recombinant NIb of PVY in PTA-ELISA. Two of them specifically detected native NIb of potato A, potato V, potato Y, plum pox and turnip mosaic potyviruses in extracts of infected plants in Western blots. Time course experiments revealed that NIb protein can be first detected on the fifth day after infection. 相似文献
897.
Rodolphe E Gozlan Demetra Andreou Takashi Asaeda Kathleen Beyer Rachid Bouhadad Dean Burnard Nuno Caiola Predrag Cakic Vesna Djikanovic Hamid R Esmaeili Istvan Falka Duncan Golicher Akos Harka Galina Jeney Vladimír Kováč Jiří Musil Annamaria Nocita Meta Povz Nicolas Poulet Tomas Virbickas Christian Wolter A Serhan Tarkan Elena Tricarico Teodora Trichkova Hugo Verreycken Andrzej Witkowski Chun Guang Zhang Irene Zweimueller J Robert Britton 《Fish and Fisheries》2010,11(4):315-340
In recent years, policy‐makers have sought the development of appropriate tools to prevent and manage introductions of invasive species. However, these tools are not well suited for introductions of non‐target species that are unknowingly released alongside intentionally‐introduced species. The most compelling example of such invasion is arguably the topmouth gudgeon Pseudorasbora parva, a small cyprinid species originating from East Asia. A combination of sociological, economical and biological factors has fuelled their rapid invasion since the 1960s; 32 countries (from Central Asia to North Africa) have been invaded in less than 50 years. Based on a combination of monitoring surveys (2535 populations sampled) and literature reviews, this paper aims to quantify and characterise important invasion parameters, such as pathways of introduction, time between introduction and detection, lag phase and plasticity of life history traits. Every decade, five new countries have reported P. parva introduction, mainly resulting from the movement of Chinese carps for fish farming. The mean detection period after first introduction was 4 years, a duration insufficient to prevent their pan‐continental invasion. High phenotypic plasticity in fitness related traits such as growth, early maturity, fecundity, reproductive behaviour and the ability to cope with novel pathogens has predisposed P. parva to being a strong invader. The Pseudorasbora parva invasion has provided quantitative data for the development of 1) early warning systems across different spatial scales; 2) rapid eradication programmes prior to natural spread in open systems and 3) sound risk assessments with emphasis on plasticity of life history traits. 相似文献
898.
The surface properties of glutens isolated from a durum wheat cultivar (Capeiti) and two bread wheats (Riband and Hereward) were investigated using intrinsic and extrinsic fluorescence. Intrinsic fluorescence decreased on increasing protein concentration and increased after urea addition. The extrinsic fluorescence was evaluated by a titration with 8‐anilino‐1‐naphthalene sulphonate (ANS), an hydrophobic probe. The saturating concentration for ANS and its dissociation constant (Kd) were determined. The hydrophobicity of durum and bread wheat gluten showed a different behavior increasing the protein concentration: Capeiti was not influenced, but there was a change on the gluten surface for Riband and Hereward. The significance in understanding gluten structure and the relevance of the surface properties are discussed. 相似文献
899.
Aleksandra Kvetkina Elena Kostina Irina Gladkikh Victoria Chausova Ekaterina Yurchenko Irina Bakunina Mikhail Pivkin Stanislav Anastyuk Roman Popov Margarita Monastyrnaya Emma Kozlovskaya Marina Isaeva Pavel Dmitrenok Elena Leychenko 《Marine drugs》2021,19(12)
The peculiarities of the survival and adaptation of deep-sea organisms raise interest in the study of their metabolites as promising drugs. In this work, the hemolytic, cytotoxic, antimicrobial, and enzyme-inhibitory activities of tentacle extracts from five species of sea anemones (Cnidaria, orders Actiniaria and Corallimorpharia) collected near the Kuril and Commander Islands of the Far East of Russia were evaluated for the first time. The extracts of Liponema brevicorne and Actinostola callosa demonstrated maximal hemolytic activity, while high cytotoxic activity against murine splenocytes and Ehrlich carcinoma cells was found in the extract of Actinostola faeculenta. The extracts of Corallimorphus cf. pilatus demonstrated the greatest activity against Ehrlich carcinoma cells but were not toxic to mouse spleen cells. Sea anemones C. cf. pilatus and Stomphia coccinea are promising sources of antimicrobial and antifungal compounds, being active against Gram-positive bacteria Bacillus subtilis, Staphylococcus aureus, and yeast Candida albicans. Moreover, all sea anemones contain α-galactosidase inhibitors. Peptide mass fingerprinting of L. brevicorne and C. cf. pilatus extracts provided a wide range of peptides, predominantly with molecular masses of 4000–5900 Da, which may belong to a known or new structural class of toxins. The obtained data allow concluding that deep-sea anemones are a promising source of compounds for drug discovery. 相似文献
900.
David Bowen Michael Blackburn Thomas A Rocheleau Olga Andreev Elena Golubeva Richard H ffrench-Constant 《Pest management science》1999,55(6):666-668
Four toxin complexes, Tca, Tcb, Tcc and Tcd from the culture broth of Photorhabdus luminescens have been purified and the four toxin complex encoding loci, tca, tcb, tcc and tcd, cloned. Genetic knockout of either tca or tcd reduced oral toxicity to Manduca sexta, and knockout of both loci eliminated activity. Purified Tca specifically affected the insect midgut, despite its putative normal delivery directly into the insect haemocel. These Photorhabdus toxins may form useful alternatives to other orally active bacterial protein toxins such as those from Bacillus thuringiensis. 相似文献