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51.
Annamaria Sinisi Barbara Calcinai Carlo Cerrano Henny A. Dien Angela Zampella Claudio D’Amore Barbara Renga Stefano Fiorucci Orazio Taglialatela-Scafati 《Bioorganic & medicinal chemistry》2013,21(17):5332-5338
Chemical investigation of an Indonesian specimen of Theonella swinhoei afforded the new dimeric macrolides isoswinholide B (5) and swinholide K (6), along with the known swinholides A (1), B (2) and D (3) and isoswinholide A (4). Isoswinholide B showed an unprecedented 21/19′ lactonization pattern, while swinholide K included an sp2 methylene attached at C-4 and an additional oxymethine group at C-5, whose configuration has been determined through application of J-based configuration analysis. The isolated swinholides (1–6), with the exception of isoswinholide B, showed a cytotoxic activity on HepG2 (hepatocarcinoma cell line) in the nanomolar range. 相似文献
52.
Jun Zhang Kevin A. Fengler John L. Van Hemert Rajeev Gupta Nick Mongar Jindong Sun William B. Allen Yang Wang Benjamin Weers Hua Mo Renee Lafitte Zhenglin Hou Angela Bryant Farag Ibraheem Jennifer Arp Kankshita Swaminathan Stephen P. Moose Bailin Li Bo Shen 《Plant biotechnology journal》2019,17(12):2272-2285
53.
Genevieve G. A. Fouda Joshua D. Amos Andrew B. Wilks Justin Pollara Caroline A. Ray Anjali Chand Erika L. Kunz Brooke E. Liebl Kaylan Whitaker Angela Carville Shannon Smith Lisa Colvin David J. Pickup Herman F. Staats Glenn Overman Krissey Eutsey-Lloyd Robert Parks Haiyan Chen Celia LaBranche Susan Barnett Georgia D. Tomaras Guido Ferrari David C. Montefiori Hua-Xin Liao Norman L. Letvin Barton F. Haynes Sallie R. Permar 《Journal of virology》2013,87(12):6986-6999
We previously demonstrated that vaccination of lactating rhesus monkeys with a DNA prime/vector boost strategy induces strong T-cell responses but limited envelope (Env)-specific humoral responses in breast milk. To improve vaccine-elicited antibody responses in milk, hormone-induced lactating rhesus monkeys were vaccinated with a transmitted/founder (T/F) HIV Env immunogen in a prime-boost strategy modeled after the moderately protective RV144 HIV vaccine. Lactating rhesus monkeys were intramuscularly primed with either recombinant DNA (n = 4) or modified vaccinia virus Ankara (MVA) poxvirus vector (n = 4) expressing the T/F HIV Env C.1086 and then boosted twice intramuscularly with C.1086 gp120 and the adjuvant MF59. The vaccines induced Env-binding IgG and IgA as well as neutralizing and antibody-dependent cellular cytotoxicity (ADCC) responses in plasma and milk of most vaccinated animals. Importantly, plasma neutralization titers against clade C HIV variants MW965 (P = 0.03) and CAP45 (P = 0.04) were significantly higher in MVA-primed than in DNA-primed animals. The superior systemic prime-boost regimen was then compared to a mucosal-boost regimen, in which animals were boosted twice intranasally with C.1086 gp120 and the TLR 7/8 agonist R848 following the same systemic prime. While the systemic and mucosal vaccine regimens elicited comparable levels of Env-binding IgG antibodies, mucosal immunization induced significantly stronger Env-binding IgA responses in milk (P = 0.03). However, the mucosal regimen was not as potent at inducing functional IgG responses. This study shows that systemic MVA prime followed by either intranasal or systemic protein boosts can elicit strong humoral responses in breast milk and may be a useful strategy to interrupt postnatal HIV-1 transmission. 相似文献
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55.
There is a continuing need for monitoring the health of the environment due to the presence of pollutants. Here, we review the development and attributes of biosensors by which bacteria have been genetically modified to express the luminescence genes, i.e. to glow, in a quantified manner, in response to pollutants. We have concentrated on the detection of organic hydrocarbon pollutants and discussed the molecular mechanisms by which some of these chemicals act as effector molecules on the respective regulatory systems. The future of environmental biosensors is predictably bright. As more knowledge is gathered on the sensing regulatory component, the possibility of developing targeted or pollutant-specific biosensors is promising. Moreover, the repertoire of biosensors for culprit organic pollutants is expected to be enlarged through advances in genomics technology and identification of new sensory or receptor molecules. The need for pollutant detection at concentrations in the parts per trillion range or biosensors configured in a nanoscale is anticipated. 相似文献
56.
A deliberate approach to screening for initial crystallization conditions of biological macromolecules 总被引:4,自引:0,他引:4
Luft JR Collins RJ Fehrman NA Lauricella AM Veatch CK DeTitta GT 《Journal of structural biology》2003,142(1):170-179
A method to rationally predict crystallization conditions for a previously uncrystallized macromolecule has not yet been developed. One way around this problem is to determine initial crystallization conditions by casting a wide net, surveying a large number of chemical and physical conditions to locate crystallization leads. A facility that executes the rapid survey of crystallization lead conditions is described in detail. Results and guidelines for the initial screening of crystallization conditions, applicable to both manual and robotic setups, are discussed. 相似文献
57.
Zegre Cannon C Kissling GE Goulding DR King-Herbert AP Blankenship-Paris T 《Lab animal》2011,40(3):85-93
In this study, the authors evaluated the analgesic efficacy of tramadol (an opioid-like analgesic), carprofen (a nonsteroidal anti-inflammatory drug) and a combination of both drugs (multimodal therapy) in a rat laparotomy model. The authors randomly assigned rats to undergo either surgery (abdominal laparotomy with visceral manipulation and anesthesia) or anesthesia only. Rats in each group were treated with tramadol (12.5 mg per kg body weight), carprofen (5 mg per kg body weight), a combination of tramadol and carprofen (12.5 mg per kg body weight and 5 mg per kg body weight, respectively) or saline (anesthesia control group only; 5 mg per kg body weight). The authors administered analgesia 10 min before anesthesia, 4 h after surgery or (for the rats that received anesthesia only) anesthesia and 24 h after surgery or anesthesia. They measured locomotor activity, running wheel activity, feed and water consumption, body weight and fecal corticosterone concentration of each animal before and after surgery. Clinical observations were made after surgery or anesthesia to evaluate signs of pain and distress. The authors found that carprofen, tramadol and a combination of carprofen and tramadol were all acceptable analgesia regimens for a rat laparotomy model. 相似文献
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59.
Continental South Africa has a coastline of some 3,650 km and an Exclusive Economic Zone (EEZ) of just over 1 million km2. Waters in the EEZ extend to a depth of 5,700 m, with more than 65% deeper than 2,000 m. Despite its status as a developing nation, South Africa has a relatively strong history of marine taxonomic research and maintains comprehensive and well-curated museum collections totaling over 291,000 records. Over 3 million locality records from more than 23,000 species have been lodged in the regional AfrOBIS (African Ocean Biogeographic Information System) data center (which stores data from a wider African region). A large number of regional guides to the marine fauna and flora are also available and are listed.The currently recorded marine biota of South Africa numbers at least 12,914 species, although many taxa, particularly those of small body size, remain poorly documented. The coastal zone is relatively well sampled with some 2,500 samples of benthic invertebrate communities have been taken by grab, dredge, or trawl. Almost none of these samples, however, were collected after 1980, and over 99% of existing samples are from depths shallower than 1,000 m—indeed 83% are from less than 100 m. The abyssal zone thus remains almost completely unexplored.South Africa has a fairly large industrial fishing industry, of which the largest fisheries are the pelagic (pilchard and anchovy) and demersal (hake) sectors, both focused on the west and south coasts. The east coast has fewer, smaller commercial fisheries, but a high coastal population density, resulting in intense exploitation of inshore resources by recreational and subsistence fishers, and this has resulted in the overexploitation of many coastal fish and invertebrate stocks. South Africa has a small aquaculture industry rearing mussels, oysters, prawns, and abalone—the latter two in land-based facilities.Compared with many other developing countries, South Africa has a well-conserved coastline, 23% of which is under formal protection, however deeper waters are almost entirely excluded from conservation areas. Marine pollution is confined mainly to the densely populated KwaZulu-Natal coast and the urban centers of Cape Town and Port Elizabeth. Over 120 introduced or cryptogenic marine species have been recorded, but most of these are confined to the few harbors and sheltered sites along the coast. 相似文献
60.
Rubio A Rambla JL Santaella M Gómez MD Orzaez D Granell A Gómez-Gómez L 《The Journal of biological chemistry》2008,283(36):24816-24825
Saffron, the processed stigma of Crocus sativus, is characterized by the presence of several apocarotenoids that contribute to the color, flavor, and aroma of the spice. However, little is known about the synthesis of aroma compounds during the development of the C. sativus stigma. The developing stigma is nearly odorless, but before and at anthesis, the aromatic compound beta-ionone becomes the principal norisoprenoid volatile in the stigma. In this study, four carotenoid cleavage dioxygenase (CCD) genes, CsCCD1a, CsCCD1b, CsCCD4a, and CsCCD4b, were isolated from C. sativus. Expression analysis showed that CsCCD1a was constitutively expressed, CsCCD1b was unique to the stigma tissue, but only CsCCD4a and -b had expression patterns consistent with the highest levels of beta-carotene and emission of beta-ionone derived during the stigma development. The CsCCD4 enzymes were localized in plastids and more specifically were present in the plastoglobules. The enzymatic activities of CsCCD1a, CsCCD1b, and CsCCD4 enzymes were determined by Escherichia coli expression, and subsequent analysis of the volatile products was generated by GC/MS. The four CCDs fell in two phylogenetically divergent dioxygenase classes, but all could cleave beta-carotene at the 9,10(9',10') positions to yield beta-ionone. The data obtained suggest that all four C. sativus CCD enzymes may contribute in different ways to the production of beta-ionone. In addition, the location and precise timing of beta-ionone synthesis, together with its known activity as a fragrance and insect attractant, suggest that this volatile may have a role in Crocus pollination. 相似文献