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1.
Soman (pinacolyl methylphosphonofluoridate), a mixture of four stereoisomers, is inactivated appreciably in Tris buffer, pH 7.40, mu = 0.155 at 25 degrees C by beta-cyclodextrin (cycloheptaamylose, beta-CD). Under these conditions, the dissociation constant Kd of the 1:1 complex formed by beta-CD and soman and the rate constant k2 for the phosphonylation of beta-CD by soman are (0.53 +/- 0.05)mM and (5.9 +/- 0.6) X 10(-2) min-1 respectively. It results that the inactivation of soman by the mono-anion of beta-CD is about 2,600 times faster than the hydrolysis of soman by the hydroxide ion. The inactivation of both P(-) isomers of soman by beta-CD proceeds apparently at the same rate but both P(+) isomers react more slowly. Thus the interaction is stereospecific. The inactivation of soman by beta-CD appears to be as fast in human plasma in vitro as in Tris buffer.  相似文献   
2.
We investigated the occurrence of postconflict social interactions in a group of Barbary macaques (Macaca sylvanus)that live in a large enclosure. We collected data during the mating and the nonmating seasons and analyzed them via two methods. Separate analyses for the two seasons yielded very similar results. Reconciliation and redirection occurred. But we found no evidence for consolation and postconflict kin-oriented affiliation. The consistency of these findings with those on other species of Macacaindicates that reconciliation and redirection are typical postconflict social interactions of macaque victims.  相似文献   
3.
4.

Background

Ad35.CS.01 is a pre-erythrocytic malaria candidate vaccine. It is a codon optimized nucleotide sequence representing the P. falciparum circumsporozoite (CS) surface antigen inserted in a replication deficient Adenovirus 35 backbone. A Phase 1a trial has been conducted in the USA in naïve adults and showed that the vaccine was safe. The aim of this study is to assess the safety and immunogenicity of ascending dosages in sub Saharan Africa.

Methods

A double blind, randomized, controlled, dose escalation, phase Ib trial was conducted in a rural area of Balonghin, the Saponé health district (Burkina Faso). Forty-eight healthy adults aged 18-45 years were randomized into 4 cohorts of 12 to receive three vaccine doses (day 0, 28 and 84) of 109, 1010, 5X1010, 1011 vp of Ad35.CS.01 or normal saline by intra muscular injection. Subjects were monitored carefully during the 14 days following each vaccination for non serious adverse events. Severe and serious adverse events were collected throughout the participant study duration (12 months from the first vaccination). Humoral and cellular immune responses were measured on study days 0, 28, 56, 84, 112 and 140.

Results

Of the forty-eight subjects enrolled, forty-four (91.7%) received all three scheduled vaccine doses. Local reactions, all of mild severity, occurred in thirteen (27.1%) subjects. Severe (grade 3) laboratory abnormalities occurred in five (10.4%) subjects. One serious adverse event was reported and attributed to infection judged unrelated to vaccine. The vaccine induced both antibody titers and CD8 T cells producing IFNγ and TNFα with specificity to CS while eliciting modest neutralizing antibody responses against Ad35.

Conclusion

Study vaccine Ad35.CS.01 at four different dose levels was well-tolerated and modestly immunogenic in this population. These results suggest that Ad35.CS.01 should be further investigated for preliminary efficacy in human challenge models and as part of heterologous prime-boost vaccination strategies.

Trial Registration

ClinicalTrials.gov NCT01018459 http://clinicaltrials.gov/ct2/show/NCT01018459  相似文献   
5.
Deoxynojirimycin (DNJ) based imino sugars display antiviral activity in the tissue culture surrogate model of Hepatitis C (HCV), bovine viral diarrhoea virus (BVDV), mediated by inhibition of ER α-glucosidases. Here, the antiviral activities of neoglycoconjugates derived from deoxynojirimycin, and a novel compound derived from deoxygalactonojirimycin, by click chemistry with functionalised adamantanes are presented. Their antiviral potency, in terms of both viral infectivity and virion secretion, with respect to their effect on α-glucosidase inhibition, are reported. The distinct correlation between the ability of long alkyl chain derivatives to inhibit ER α-glucosidases and their anti-viral effect is demonstrated. Increasing alkyl linker length between DNJ and triazole groups increases α-glucosidase inhibition and reduces the production of viral progeny RNA and the maturation of the envelope polypeptide. Disruption to viral glycoprotein processing, with increased glucosylation on BVDV E2 species, is representative of α-glucosidase inhibition, whilst derivatives with longer alkyl linkers also show a further decrease in infectivity of secreted virions, an effect proposed to be distinct from α-glucosidase inhibition.  相似文献   
6.
Monthly stem increment of 766 trees was assessed for 7 years in Kakamega Forest, Kenya and related to monthly climatic variables. Mean stem increment of all tree individuals correlated negatively with maximum temperature but not with mean and minimum temperatures. For the precipitation variables sum of precipitation and number of rainy days we found positive correlations. Stem increment of the trees in the early-, mid-, and late-successional groups correlated positively with the number of rainy days. For late-successional trees increment correlated negatively with mean and maximum temperature and positively with all other precipitation variables. For mid-successional trees we found a negative correlation with mean temperature. In addition, the stem increment of most species related positively to precipitation variables and negatively to mean and maximum temperature. In view of the expected increasing temperatures and fewer but heavier rain events, our results suggest that climate change will lead to a reduction in stem increment. The results appertaining to the successional groups imply that early and mid-successional species are better equipped to perform well under the expected future climatic conditions than the late-successional species. This could reduce the role of this East African forest as a carbon store. As the responses to climatic variables were highly group- and species-specific it is likely that climate change will result in a species composition shift, presumably in favour of drought-resistant and heat-tolerating species.  相似文献   
7.
Gnanvossou D  Hanna R  Dicke M 《Oecologia》2003,135(1):84-90
Carnivorous arthropods exhibit complex intraspecific and interspecific behaviour among themselves when they share the same niche or habitat and food resources. They should simultaneously search for adequate food for themselves and their offspring and in the meantime avoid becoming food for other organisms. This behaviour is of great ecological interest in conditions of low prey availability. We examined by means of an olfactometer, how volatile chemicals from prey patches with conspecific or heterospecific predators might contribute to shaping the structure of predator guilds. To test this, we used the exotic predatory mites Typhlodromalus manihoti and T. aripo, and the native predatory mite Euseius fustis, with Mononychellus tanajoa as the common prey species for the three predatory mite species. We used as odour sources M. tanajoa-infested cassava leaves or apices with or without predators. T. manihoti avoided patches inhabited by the heterospecifics T. aripo and E. fustis or by conspecifics when tested against a patch without predators. Similarly, both T. aripo and E. fustis females avoided patches with con- or heterospecifics when tested against a patch without predators. When one patch contained T. aripo and the other T. manihoti, females of the latter preferred the patch with T. aripo. Thus, T. manihoti is able to discriminate between odours from patches with con- and heterospecifics. Our results show that the three predatory mite species are able to assess prey patch profitability using volatiles. Under natural conditions, particularly when their food sources are scarce, the three predatory mite species might be involved in interspecific and/or intraspecific interactions that can substantially affect population dynamics of the predators and their prey.  相似文献   
8.
In vitro experiments using [1-(14)C] and [2-(14)C]acetate were devised to study the biosynthesis of the defensive coccinellid alkaloids adaline and coccinelline in Adalia 2-punctata and Coccinella 7-punctata, respectively. The labelled alkaloids obtained in these experiments had a specific activity about ten times higher than that of the samples obtained in feeding experiments. This in vitro assay has enabled us to demonstrate that these two alkaloids are most likely biosynthesised through a fatty acid rather than a polyketide pathway, that glutamine is the preferred source of the nitrogen atom and that alkaloid biosynthesis takes place in the insect fat body.  相似文献   
9.

Objectives

To investigate DKK-1 and SOST serum levels among patients with recent inflammatory back pain (IBP) fulfilling ASAS criteria for SpA and associated factors.

Methods

The DESIR cohort is a prospective, multicenter French cohort of 708 patients with early IBP (duration >3 months and <3 years) suggestive of AxSpA. DKK-1 and SOST serum levels were assessed at baseline and were compared between the subgroup of patients fulfilling ASAS criteria for SpA (n = 486; 68.6%) and 80 healthy controls.

Results

Mean SOST serum levels were lower in ASAS+ patients than healthy controls (49.21 ± 25.9 vs. 87.8 ± 26 pmol/L; p<0.0001). In multivariate analysis, age (p = 5.4 10−9), CRP level (p<0.0001) and serum DKK-1 level (p = 0.001) were associated with SOST level. Mean DKK-1 serum levels were higher in axial SpA patients than controls (30.03 ± 15.5 vs. 11.6 ± 4.2 pmol/L; p<0.0001). In multivariate analysis, DKK-1 serum levels were associated with male gender (p = 0.03), CRP level (p = 0.006), SOST serum level (p = 0.002) and presence of sacroiliitis on radiography (p = 0.05). Genetic association testing of 10 SNPs encompassing the DKK-1 locus failed to demonstrate a significant contribution of genetics to control of DKK-1 serum levels.

Conclusions

DKK-1 serum levels were increased and SOST levels were decreased among a large cohort of patients with early axial SpA compared to healthy controls. DKK-1 serum levels were mostly associated with biological inflammation and SOST serum levels.  相似文献   
10.
Biological control as an alternative to chemical pesticides is of increasing public interest. However, to ensure safe use of biocontrol methods, strategies to assess the possible risks need to be developed. The production of toxic metabolites is an aspect which has so far largely been neglected in the risk assessment and the registration process for biocontrol products. We have evaluated the risks of elsinochrome A (ELA) and leptosphaerodione production by the fungus Stagonospora convolvuli LA39, an effective biocontrol agent used against bindweeds. The toxicity of the two metabolites to bacteria, protozoa, fungi and plants was evaluated in in vitro assays. The most sensitive bacteria and fungi were already affected at 0.01-0.07 microM ELA, whereas plants were far less sensitive. Leptosphaerodione was less toxic than ELA. Subsequently, it was investigated whether ELA is present in the applied biocontrol product or LA39-treated bindweed and crop plants. In plants ELA was never detected and in the biocontrol product the ELA concentration was far too low to have toxic effects even on the most sensitive organisms. We conclude that the production of ELA by biocontrol strain LA39 does not pose a risk to the environment or to the consumer.  相似文献   
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