Interactome Screening Identifies the ER Luminal Chaperone Hsp47 as a Regulator of the Unfolded Protein Response Transducer IRE1α

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Combined Antimicrobial Resistance in Enterococcus faecium Isolated from Chickens

Nineteen E. faecium strains isolated from chicken caecum samples, collected in slaughterhouses and highly resistant to vancomycin or gentamicin, were coresistant to erythromycin, and/or tetracyclines, and/or streptogramins, and/or avilamycin. Multiple antibiotic resistance was related to the presence in various combinations of aac(6′)-aph(2"), erm(B), emtA, mef(A), tet(L), tet(M), and vanA genes.     

Tumor-associated antigen human chorionic gonadotropin beta contains numerous antigenic determinants recognized by in vitro-induced CD8+ and CD4+ T lymphocytes

The beta subunit of human chorionic gonadotropin (hCG beta) is markedly overexpressed by neoplastic cells of differing histological origin including those present in colon, breast, prostate and bladder tumors. We have previously shown that some patients with hCG beta-producing urothelial tumors have circulating T cells that proliferate in response to hCG beta. To make a comprehensive study of hCG beta as a potential target for cancer immunotherapy, we investigated whether hCG beta peptides could induce CD4+ or CD8+ T-cell responses in vitro. By stimulating peripheral blood mononuclear cells (PBMCs) from three donors with mixtures of overlapping 16-mer synthetic peptides analogous to portions of either the hCG beta 20-71 or the hCG beta 102-129 region, we established six CD4+ T-cell lines that proliferated specifically in response to five distinct determinants located within these two hCG beta regions. Three antigenic determinants (hCG beta 52-67, 106-121 and 114-125) were presented by HLA-DR molecules, while the two other antigenic determinants (hCG beta 48-63 and 56-67) were presented by HLA-DQ molecules. Interestingly, one T-cell line specific for peptide hCG beta 106-121 recognized hCG beta peptides comprising, at position 117, either an alanine or an aspartic acid residue, with the latter residue being present within the protein expressed by some tumor cells. In addition, three other hCG beta-derived peptides that exhibited HLA-A*0201 binding ability were able to stimulate CD8+ cytotoxic T cells from two HLA-A*0201 donors. These three immunogenic peptides corresponded to regions hCG beta 40-48, hCG beta 44-52 and hCG beta 75-84. Our results indicate that the tumor-associated antigen hCG beta possesses numerous antigenic determinants liable to stimulate CD4+ and CD8+ T lymphocytes, and might thus be an effective target antigen for the immunotherapy of hCG beta-producing tumors.     

The Zinc Center Influences the Redox and Thermodynamic Properties of Escherichia coli Thioredoxin 2

Thioredoxins are small, ubiquitous redox enzymes that reduce protein disulfide bonds by using a pair of cysteine residues present in a strictly conserved WCGPC catalytic motif. The Escherichia coli cytoplasm contains two thioredoxins, Trx1 and Trx2. Trx2 is special because it is induced under oxidative stress conditions and it has an additional N-terminal zinc-binding domain. We have determined the redox potential of Trx2, the pK_a of the active site nucleophilic cysteine, as well as the stability of the oxidized and reduced form of the protein. Trx2 is more oxidizing than Trx1 (-221 mV versus -284 mV, respectively), which is in good agreement with the decreased value of the pK_a of the nucleophilic cysteine (5.1 versus 7.1, respectively). The difference in stability between the oxidized and reduced forms of an oxidoreductase is the driving force to reduce substrate proteins. This difference is smaller for Trx2 (ΔΔG°_H2O = 9 kJ/mol and ΔT_m = 7. 4 °C) than for Trx1 (ΔΔG°_H2O = 15 kJ/mol and ΔT_m = 13 °C). Altogether, our data indicate that Trx2 is a significantly less reducing enzyme than Trx1, which suggests that Trx2 has a distinctive function. We disrupted the zinc center by mutating the four Zn²⁺-binding cysteines to serine. This mutant has a more reducing redox potential (-254 mV) and the pK_a of its nucleophilic cysteine shifts from 5.1 to 7.1. The removal of Zn²⁺ also decreases the overall stability of the reduced and oxidized forms by 3.2 kJ/mol and 5.8 kJ/mol, respectively. In conclusion, our data show that the Zn²⁺-center of Trx2 fine-tunes the properties of this unique thioredoxin.     

Physical maturation,life‐history classes and age estimates of free‐ranging western gorillas—insights from Mbeli Bai,Republic of Congo

Physical maturation and life‐history parameters are seen as evolutionary adaptations to different ecological and social conditions. Comparison of life‐history patterns of closely related species living in diverse environments helps to evaluate the validity of these assumptions but empirical data are lacking. The two gorilla species exhibit substantial differences in their environment, which allows investigation into the role of increased frugivory in shaping western gorilla life histories. We present behavioral and morphological data on western gorilla physical maturation and life‐history parameters from a 12.5‐year study at Mbeli Bai, a forest clearing in the Nouabalé‐Ndoki National Park in northern Congo. We assign photographs of known individuals to different life‐history classes and propose new age boundaries for life‐history classes in western gorillas, which can be used and tested at other western gorilla research sites. Our results show that western gorillas are weaned at a later age compared with mountain gorillas and indicate slower physical maturation of immatures. These findings support the risk‐aversion hypothesis for more frugivorous species. However, our methods need to be applied and tested with other gorilla populations. The slow life histories of western gorillas could have major consequences for social structure, mortality patterns and population growth rates that will affect recovery from population crashes of this critically endangered species. We emphasize that long‐term studies can provide crucial demographic and life‐history data that improve our understanding of life‐history evolution and adaptation and help to refine conservation strategies. Am. J. Primatol. 71:106–119, 2009. © 2008 Wiley‐Liss, Inc.     

Predicting global habitat suitability for stony corals on seamounts

Aim Globally, species distribution patterns in the deep sea are poorly resolved, with spatial coverage being sparse for most taxa and true absence data missing. Increasing human impacts on deep‐sea ecosystems mean that reaching a better understanding of such patterns is becoming more urgent. Cold‐water stony corals (Order Scleractinia) form structurally complex habitats (dense thickets or reefs) that can support a diversity of other associated fauna. Despite their widely accepted ecological importance, records of scleractinian corals on seamounts are patchy and simply not available for most of the global ocean. The objective of this paper is to model the global distribution of suitable habitat for stony corals on seamounts. Location Seamounts worldwide. Methods We compiled a database containing all accessible records of scleractinian corals on seamounts. Two modelling approaches developed for presence‐only data were used to predict global habitat suitability for seamount scleractinians: maximum entropy modelling (Maxent) and environmental niche factor analysis (ENFA). We generated habitat‐suitability maps and used a cross‐validation process with a threshold‐independent metric to evaluate the performance of the models. Results Both models performed well in cross‐validation, although the Maxent method consistently outperformed ENFA. Highly suitable habitat for seamount stony corals was predicted to occur at most modelled depths in the North Atlantic, and in a circumglobal strip in the Southern Hemisphere between 20° and 50° S and shallower than around 1500 m. Seamount summits in most other regions appeared much less likely to provide suitable habitat, except for small near‐surface patches. The patterns of habitat suitability largely reflect current biogeographical knowledge. Environmental variables positively associated with high predicted habitat suitability included the aragonite saturation state, and oxygen saturation and concentration. By contrast, low levels of dissolved inorganic carbon, nitrate, phosphate and silicate were associated with high predicted suitability. High correlation among variables made assessing individual drivers difficult. Main conclusions Our models predict environmental conditions likely to play a role in determining large‐scale scleractinian coral distributions on seamounts, and provide a baseline scenario on a global scale. These results present a first‐order hypothesis that can be tested by further sampling. Given the high vulnerability of cold‐water corals to human impacts, such predictions are crucial tools in developing worldwide conservation and management strategies for seamount ecosystems.     

Shared Decision Making Does Not Influence Physicians against Clinical Practice Guidelines

Background

While shared decision making (SDM) and adherence to clinical practice guidelines (CPGs) are important, some believe they are incompatible. This study explored the mutual influence between physicians’ intention to engage in SDM and their intention to follow CPGs.

Methods

Embedded within a clustered randomized trial to assess the impact of training physicians in SDM about using antibiotics to treat acute respiratory tract infections, this study evaluated physicians’ intentions to both engage in SDM and follow CPGs. A self-administered questionnaire based on the theory of planned behavior evaluated both behavioral intentions and their respective determinants (attitude, subjective norm and perceived behavioral control) at study entry and exit. We used path analysis to explore the relationships between the intentions. We conducted statistical analyses using the maximum likelihood method and the variance-covariance matrix. Goodness of fit indices encompassed the chi-square statistic, the comparative fit index and the root mean square error of approximation.

Results

We analyzed 244 responses at entry and 236 at exit. In the control group, at entry we observed that physicians’ intention to engage in SDM (r = 0, t = 0.03) did not affect their intention to follow CPGs; however, their intention to follow CPGs (r = −0.31 t = −2.82) did negatively influence their intention to engage in SDM. At exit, neither behavioral intention influenced the other. In the experimental group, at entry neither behavioral intention influenced the other; at exit, the intention to engage in SDM still did not influence the intention to use CPGs, although the intention to follow CPGs (r = −0.15 t = −2.02) slightly negatively influenced the intention to engage in SDM, but this was not clinically significant.

Conclusion

Physicians’ intention to engage in SDM does not affect their intention to adopt CPGs even after SDM training. Physicians’ intention to adopt CPGs had no clinically significant influence on intention to engage in SDM.

Trial Registration

ClinicalTrials.gov {"type":"clinical-trial","attrs":{"text":"NCT01116076","term_id":"NCT01116076"}}NCT01116076     

Female-specific DNA sequences in the chicken genome

Eight in silico W-specific sequences from the WASHUC1 chicken genome assembly gave female-specific PCR products using chicken DNA. Some of these fragments gave female-specific products with turkey and peacock DNA. Sequence analysis of these 8 fragments (3077 bp total) failed to detect any polymorphisms among 10 divergent chickens. In contrast, comparison of the DNA sequences of chicken with those of turkey and peacock revealed a nucleotide difference every 25 and 28 bp, respectively. Radiation hybrid mapping verified that these amplicons exist only on chromosome W. The homology of 6 W-specific fragments with chromo-helicase-DNA-binding gene and expressed sequenced tags from chicken and other species indicate that these fragments may have or have had a biological function. These fragments may be used for early sexing in commercial chicken and turkey flocks.     

Altered brain lipid composition in cyclooxygenase-2 knockout mouse

Cyclooxygenase (COX)-2 plays an important role in brain arachidonic acid (20:4n-6) metabolism, and its expression is upregulated in animal models of neuroinflammation and excitotoxicity. Our hypothesis was that brain lipid composition would be altered in COX-2 knockout (COX-2(-/-)) compared with wild-type (COX-2(+/+)) mice, reflecting the important role of COX-2 in brain lipid metabolism. Concentrations of different lipids were measured in high-energy microwaved brain from COX-2(-/-) and COX-2(+/+) mice. Compared with the COX-2(+/+) mouse brain, the brain of the COX-2(-/-) mouse had a statistically significant 15% increase in phosphatidylserine (PtdSer) and significant 37, 27, and 32% reductions in triacylglycerol and cholesterol concentrations and in the cholesterol-to-phospholipid ratio, respectively. The normalized concentration of palmitic acid (16:0) was increased in PtdSer, as was the brain concentration of unesterified arachidic acid (20:0). A lifetime absence of COX-2 produces multiple changes in brain lipid composition. These changes may be related to reported changes in fatty acid kinetics and in resistance to neuroinflammation and excitotoxicity in the COX-2(-/-) mouse.