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1.
We used two measures to compare the effectiveness of 52 conservation criteria in achieving conservation targets for forest types. The first measure was efficiency. Although widely used, efficiency assumes no loss or reduction of biodiversity features before conservation is implemented. This is invalid in many situations. Often, it is more realistic to assume gradual implementation accompanied by incremental, predictable reduction and loss of biodiversity features. We simulated future landscapes resulting from the annual interplay of loss and conservation of forest types. We then based our second measure, retention, on how well criteria scheduled conservation action to prevent targets being compromised. The simulations partly support predictions about the best criteria for scheduling implementation with continuing biodiversity loss. Retention was weakly related or unrelated to efficiency across 52 criteria. Although retention values were sensitive to changes in targets and rates of conservation and forest loss, one criterion consistently produced highest retention values.  相似文献   

2.
Previous findings showing that people are reluctant to contact morally disgusting objects such as Nazi clothing have been interpreted as showing that immorality is perceived as physically contaminating. However, self-presentation concerns could underlie the apparent contagiousness of immorality: associating visibly with immoral stimuli risks reputation damage because observers infer immorality by association. In a scenario, participants preferred to wear a Nazi armband under rather than over their clothing, despite the under choice requiring skin contact (Study 1). And participants reported being primarily motivated by reputation, not contamination. Studies 1a and 1b revealed that, when public display was kept constant to minimize reputation concerns, skin contact increased discomfort by a small amount. A lab study using a real Nazi armband showed that the preference for hiding the armband was stronger with an audience (Study 2). Changing perspective in Study 3, third parties judged targets who made direct contact with the armband as less immoral, and even less contaminated, than those who displayed the armband. Another scenario in Study 4 revealed a strong effect of public display, but no effect of skin contact, on negative feelings about wearing an immoral t-shirt. Overall, findings suggest that apparent moral contagion effects may be explained more by self-presentation than by contamination.  相似文献   

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Background: Growth of Helicobacter pyloriin vitro depends on supplementation of the medium with blood or serum. However, these supplements often require frozen storage and can show batch‐to‐batch variation, resulting in differences in bacterial growth. In this study, we introduce the use of a commercially available, lipid‐rich supplement called AlbuMAX II® (Gibco BRL, Grand Island, NY, USA) for use as a serum/blood replacement for H. pylori culture. Materials and Methods: The growth of H. pylori on solid and liquid media was examined by comparing growth after supplementation with horse blood, fetal calf serum, β‐cyclodextrin or AlbuMAX II® (Gibco BRL). Human gastric adenocarcinoma (AGS) cellular responses to H. pylori were measured by NF‐κB luciferase assays and IL‐8 ELISA. Results: We show that the growth of H. pylori on both solid and liquid media containing AlbuMAX II® (Gibco BRL) were comparable to levels obtained on blood agar or liquid media supplemented with serum. Growth was consistently higher in media supplemented with AlbuMAX II® (Gibco BRL) than media containing β‐cyclodextrin. Furthermore, bacteria grown in AlbuMAX II® (Gibco BRL) induced proinflammatory responses in AGS cells. Conclusions: AlbuMAX II® (Gibco BRL) can be used as a serum/blood replacement for the cultivation of H. pylori in solid and liquid media. This medium could be useful for an improved understanding of H. pylori metabolism or for antigen production. Furthermore, AlbuMAX II® (Gibco BRL) may be suitable for use in remote locations, particularly in areas where frozen storage of serum may be a problem.  相似文献   

5.
To selectively target doxorubicin (Dox) to tumor tissue and thereby improve the therapeutic index and/or efficacy of Dox, matrix metalloproteinases (MMP) activated peptide–Dox prodrugs were designed and synthesized by coupling MMP-cleavable peptides to Dox. Preferred conjugates were good substrates for MMPs, poor substrates for neprilysin, an off-target proteinase, and stable in blood ex vivo. When administered to mice with HT1080 xenografts, conjugates, such as 19, preferentially released Dox in tumor relative to heart tissue and prevented tumor growth with less marrow toxicity than Dox.  相似文献   

6.
Abstract

Formulating a hydrophobic drug that is water-soluble is a pharmaceutical challenge. One way is to incorporate the drug in an amphiphilic micelle composed from an aggregation of block copolymers. Design of a good nano-micelle requires many trial-and-error attempts. In this article, we developed a computational model based on a coarse-grained molecular dynamic (MD) simulation and correlated outputs with previous studies. A good correlation shows that this model reliably simulates poly-lactic acid–poly-ethylene glycol (PLA–PEG) and poly-caprolactone (PCL)–PEG aggregation in water with and without the presence of doxorubicin.

Communicated by Ramaswamy H. Sarma  相似文献   

7.
The binding of doxorubicin to large unilamellar vesicles consisting of cardiolipin or other anionic phospholipids was analyzed in terms of the local drug concentration at the membrane surface, according to the Gouy-Chapman theory. The analysis suggests strong positive binding cooperativity. Part of the drug binds in the uncharged form. The affinity for cardiolipin and other anionic phospholipids is comparable. A binding level of 0.5 doxorubicin per lipid-phosphorus is reached when the local concentration of free doxorubicin monomer-equivalents at the membrane surface is about 0.2–0.7 mM. This contrasts with earlier findings indicating a 300–1000 fold higher affinity for cardiolipin. The present analysis provides an explanation for this apparent discrepancy.  相似文献   

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We compared histochemical and immunohistochemical staining as well as fluorochrome labeling in murine bone specimens that were fixed with 10% neutral buffered formalin to those fixed with HistoChoice®. We showed that sections from undecalcified tibiae fixed for 4 h in HistoChoice® resulted in enhanced toluidine blue and Von Kossa histochemical staining compared to formalin fixation. HistoChoice® produced comparable or improved staining for alkaline phosphatase. Acid phosphatase localization was better in formalin fixed specimens, but osteoclasts were visuralized more easily in HistoChoice® fixed specimens. As expected, immunohistochemical labeling was antibody dependent; some antibodies labeled better in HistoChoice® fixed specimens while others were better in formalin fixed specimens. Toluidine blue, Von Kossa, and alkaline phosphatase staining of sections fixed for 12 h produced sections that were similar to 4 h fixed sections. Fixation for 12 h preserved acid phosphatase activity better. Increasing fixation to 12 h affected immunolocalization differentially. Bone sialoprotein labeling in HistoChoice® fixed specimens was comparable to formalin fixed samples. On the other hand, after 12 h formalin fixation, osteocalcin labeling was comparable to HistoChoice®. For most histochemical applications, fixing murine bone specimens for 4 h with HistoChoice® yielded superior staining compared to formalin fixation. If immunohistochemical localization is desired, however, individual antibodies must be tested to determine which fixation process retains antigenicity better. In addition, there was no detectable difference in the intensity of fluorochrome labeling using either fixative. Finally, fixation duration did not alter the intensity of labeling.  相似文献   

10.
Abstract

Two metabolites of a free radical scavenger, edaravone, were synthesized. Edaravone glucuronate was synthesized by glycosylation of a glucuronic acid precursor using silver (I) trifluoromethane-sulfonate with edaravone. Edaravone sulfate was synthesized by sulfonylation of edaravone using a sulfur trioxide-pyridine complex. The two synthesized metabolites were identical to isolated metabolites. X-ray analysis identified edaravone glucuronate as β-O-glucuronate, although there were three possible edaravone glucuronate tautomers.  相似文献   

11.
The Bali mynah Species Survival Plan (SSP®), an Association of Zoos and Aquariums program, strives to maintain the genetic and demographic health of its population, avoid unplanned changes in size, and minimize the risk of population extinction. The SSP population meets current demographic and genetic objectives with a population size of 209 birds at 61 institutions and 96% genetic diversity (GD) retained from the source population. However, participating institutions have expressed concerns regarding space allocation, target population size (TPS), breeding restrictions, inbreeding depression, and harvest in relation to future population availability and viability. Based on these factors, we assess five questions with a quantitative risk assessment, specifically a population viability analysis (PVA) using ZooRisk software. Using an individual-based stochastic model, we project potential population changes under different conditions (e.g. changes in TPS and genetic management) to identify the most effective management actions. Our projections indicate that under current management conditions, population decline and extinction are unlikely and that although GD will decline over 100 years the projected loss does not exceed levels acceptable to population managers (less than 90% GD retained). Model simulations indicate that the combination of two genetic management strategies (i.e. priority breeding based on mean kinship and inbreeding avoidance) benefits the retention of GD and reduces the accumulation of inbreeding. The current TPS (250) is greater than necessary to minimize the risk of extinction for the SSP population but any reduction in TPS must be accompanied by continued application of genetic management. If carefully planned, birds can be harvested for transfer to Bali for a reintroduction program without jeopardizing the SSP population. Zoo Biol 28:230–252, 2009. © 2009 Wiley-Liss, Inc.  相似文献   

12.
One of the unique features of Helicobacter pylori is its ability to assimilate free-cholesterol (FC) into its membranes. Via FC assimilation, H. pylori strengthens the membrane lipid barrier and/or evades the host immune system. No previous studies, however, have investigated the FC uptake mechanisms of the H. pylori cell. Phosphatidylethanolamine (PE) is the most prevalent lipid component of bacteria, including H. pylori, but the function of PE remains unclear. We were therefore interested in H. pylori PE (HpPE) and investigated the interaction of its PE with cholesterols. The PE isolated from H. pylori underwent a unique molecular interaction with FC, cholesterol ester (CE), and 2,6-di-O-methyl-β-cyclodextrin (dMβCD), a sterol solubilizer. HpPE interacted not only with the FC molecule, but also with the FC-dMβCD inclusion complex. In contrast, Escherichia coli PE (EcPE), prepared as a reference PE, seemed to bind only FC, and only via a hydrophobic interaction, without binding dMβCD. HpPE was clearly more potent than EcPE in binding FC. Intriguingly, HpPE had a negligible affinity for CE, while EcPE had a high affinity for CE, comparable to its affinity for FC. Further, HpPE interacted with 3β-OH steroids, pregnenolone and dehydroepiandrosterone, in the absence of dMβCD. Gas chromatogram-mass spectrometry (GC-MS) and liquid chromatography-mass spectrometry (LC-MS) analyses revealed that the fatty acid compositions of HpPE were quite distinct from those of EcPE, and the C(14:0) fatty acid in the HpPE molecule was found to be significant in binding FC selectively. These results indicate that PE is a key candidate of nonesterified steroid-binding lipids in H. pylori.  相似文献   

13.
It has been shown in a previous paper (8) that the prime product of reassociation of related DNA sequences under open experimental conditions are mismatched duplexes which undergo maturation upon further incubation. Due to this feature, the Tm value of the duplexes of a large number of DNAs is strongly dependent on the Cot value. Here we present data showing that the Tm of the duplexes of such type of DNAs depends also on the concentration of DNA in the range of one and the same Cot value. The significance of this finding in studying the taxonomic relationship by DNA-DNA hybridisation is discussed.Abbreviations Co = initial concentration of single-stranded DNA in moles of nucleotides per liter - t = time of incubation in seconds - Cot = the product of Co and t (mol. sec. 11) - PB = an equimolar mixture of NaH2PO4 and Na2HPO4, pH 6.8 - HAP = hydroxyapatite - Ti = incubation temperature - Tm = melting temperature - Te = elution temperature, i.e. the temperature at which one half of the DNA is eluted as single strands by HAP-thermal chromatography  相似文献   

14.
The humble house mouse's cohabitation with humans has been noted since the birth of agriculture, about 10 000 years ago, in the fertile flood plains of the Middle East. In recent times, however, the mouse has been elevated from pest to model for the study of human health and disease. Recent genomics and genetics initiatives will ensure the continued growth of the house mouse as a disease model.  相似文献   

15.
《Biochemical education》1998,26(1):24-26
Most authors of current textbooks of biochemistry avoid discussing the problem of the primary source of ethanolamine or phosphatidylethanolamine in mammals. In Chinese hamster ovary cells, serine can not only be exchanged for ethanolamine in phosphatidylethanolamine, but it can also be exchanged for choline in phosphatidylcholine. This exchange of serine for choline in phosphatidylcholine thus provides a means of synthesizing ethanolamine or phosphatidylethanolamine without requiring the initial presence of ethanolamine or phosphatidylethanolamine before any molecules of ethanolamine or phosphatidylethanolamine can be synthesized.  相似文献   

16.
1 The pine beauty moth Panolis flammea has two main host plants in Britain: Pinus sylvestris (Scots pine), which is the ancestral food plant where the insect is never abundant enough to cause tree mortality, and Pinus contorta (lodgepole pine), an introduced host tree that has experienced periodic widespread tree mortality due to this pest.
2 We review the recent literature, published mostly after the year 2000, regarding the impact of natural enemies on the population dynamics of P. flammea in Britain.
3 The natural enemies of P. flammea are more diverse and abundant in Scots pine habitat than in lodgepole pine habitat and some of them show differential selection for P. flammea larvae in Scots pine habitat over those located in lodgepole pine habitat.
4 It is concluded that the difference in the population dynamics of this insect in the two different habitats was probably the result of the P. flammea finding enemy-free space in lodgepole pine habitat.
5 Recent evidence on the diversity and impact of natural enemies on lodgepole pine has demonstrated that they currently have a much more significant impact on this pest than they did in the 1970s and 1980s, when outbreaks were frequent.  相似文献   

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Density functional theory calculations were performed to evaluate the antioxidant activity of baicalein. The conformational behaviors of both the isolated and the aqueous-solvated species (simulated with the conductor-like polarizable continuum solvation model) were analyzed at the M052X/6-311 + G(d,p) level. The most stable tautomers of various forms of baicalein displayed three IHBs between O4 and OH5, O5 and OH6, and O6 and OH7. The most stable tautomer of the baicalein radical was obtained by dehydrogenating the hydroxyl at C6, while the most stable anion tautomer was obtained by deprotonating the C7 hydroxyl in gaseous and aqueous phases. The expected antioxidant activity of baicalein was explained by its ionization potentials (IPs) and homolytic O–H bond dissociation enthalpies (BDEs), which were obtained via the UM052X optimization level of the corresponding radical species. Heterolytic O–H bond cleavages (proton dissociation enthalpies, PDEs) were also computed. The calculated IP, BDE, and PDE values suggested that one-step H-atom transfer, rather than sequential proton loss–electron transfer or electron transfer–proton transfer, would be the most favorable mechanism for explaining the antioxidant activity of baicalein in the gas phase and in nonpolar solvents. In aqueous solution, the SPLET mechanism was more important.  相似文献   

19.
Botrytis cinerea is one of the most destructive pathogens of ve?getables and fruits both in the field and storage. There have been several research activities focused on developing biocontrol strategies for the pathogen due to its resistance to the commonly used synthetic fungicides. Additionally, concerns have been raised over residual effect of current synthetic fungicides used for its control. Most of these research activities have focused on Trichoderma spp., Ulocladium spp., Bacillus subtilis, plant extracts and their essential oils with some commercial products available on the market for the control of B. cinerea disease. This review summarises some of the current published information on the use of biocontrol agents and plant-based compounds for B. cinerea control. Some limitations and future prospects were also mentioned.  相似文献   

20.
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