The discovery of Streptomyces-produced streptomycin founded the age of tuberculosis therapy. Despite the subsequent development of a curative regimen for this disease, tuberculosis remains a worldwide problem, and the emergence of multidrug-resistant Mycobacterium tuberculosis has prioritized the need for new drugs. Here we show that new optimized derivatives from Streptomyces-derived griselimycin are highly active against M. tuberculosis, both in vitro and in vivo, by inhibiting the DNA polymerase sliding clamp DnaN. We discovered that resistance to griselimycins, occurring at very low frequency, is associated with amplification of a chromosomal segment containing dnaN, as well as the ori site. Our results demonstrate that griselimycins have high translational potential for tuberculosis treatment, validate DnaN as an antimicrobial target, and capture the process of antibiotic pressure-induced gene amplification.
Two experiments were conducted in order to investigate the effect of expression intensity on gender differences in the recognition of facial emotions. The first experiment compared recognition accuracy between female and male participants when emotional faces were shown with full-blown (100% emotional content) or subtle expressiveness (50%). In a second experiment more finely grained analyses were applied in order to measure recognition accuracy as a function of expression intensity (40%-100%). The results show that although women were more accurate than men in recognizing subtle facial displays of emotion, there was no difference between male and female participants when recognizing highly expressive stimuli.
Biofilms are at the root of many infections largely because they are much more antibiotic resistant than their planktonic counterparts. Antibiotics that target the biofilm phenotype are desperately needed, but there is still no standard method to assess biofilm drug susceptibility. Staphylococcus epidermidis ATCC 35984 biofilms treated with eight different approved antibiotics and five different experimental compounds were exposed to the oxidation reduction indicator Alamar blue for 60 min, and reduction relative to untreated controls was determined visually and spectrophotometrically. The minimum biofilm inhibitory concentration was defined as <50% reduction and a purplish well 60 min after the addition of Alamar blue. All of the approved antibiotics had biofilm MICs (MBICs) of >512 g/ml (most >4,096 g/ml), and four of the experimental compounds had MBICs of <128 g/ml. The experimental aaptamine derivative hystatin 3 was used to correlate Alamar blue reduction with 2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide (XTT) reduction and viable counts (CFU/ml) for S. epidermidis ATCC 35984, ATCC 12228, and two clinical isolates. For all four strains, Alamar blue results correlated well with XTT (r ؍ 0.83 to 0.97) and with CFU/ml results (r ؍ 0.85 to 0.94). Alamar blue's stability and lack of toxicity allowed CFU/ml to be determined from the same wells as Alamar blue absorbances. If the described method of microplate Alamar blue biofilm susceptibility testing, which is simple, reproducible, cost-effective, nontoxic, and amenable to high throughput, is applicable to other important biofilm forming species, it should greatly facilitate the discovery of biofilm specific agents.Given the tremendous clinical importance of biofilms, it is somewhat surprising that there is no standard method for investigating the drug susceptibility of bacterial biofilms. Several methods are available but are limited by long processing times, incompatibility with high throughput, expensive reagents or equipment, or the fact that the method measures mass instead of viability (2,4,7,13,14,24,25). For bacteria, a common method of assessing susceptibility is to quantitate the mass of biofilms by crystal violet or safranin staining, followed by extraction of bound dye with a solvent and measurement of absorption (6,24). This method provides no information about viability. Another common method of assessing bacterial biofilm susceptibility is to disrupt the biofilm by sonication, vortexing, or scraping, followed by dilution plating for determination of CFU/ml (27,28,31). This method has serious limitations; biofilm clumps can be difficult to dissociate into single-cell suspensions for plate counting, it is extremely laborious, and antibiotic carryover is a concern. For fungi, the most common method is an XTT [2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide] reduction assay (1,8,25), and this method has also been used for bacterial biofilms (1). While XTT reduction does measure metabolic activity,...
The results demonstrate that the greater effectiveness of supported employment in improving competitive work outcomes is sustained beyond 2 years and suggest that supported employment programs contribute to reduced hospitalizations and produce a higher social return on investment.
BackgroundDisordered interpersonal communication can be a serious problem in schizophrenia. Recent advances in computer-based measures allow reliable and objective quantification of nonverbal behavior. Research using these novel measures has shown that objective amounts of body and head movement in patients with schizophrenia during social interactions are closely related to the symptom profiles of these patients. In addition to and above mere amounts of movement, the degree of synchrony, or imitation, between patients and normal interactants may be indicative of core deficits underlying various problems in domains related to interpersonal communication, such as symptoms, social competence, and social functioning.MethodsNonverbal synchrony was assessed objectively using Motion Energy Analysis (MEA) in 378 brief, videotaped role-play scenes involving 27 stabilized outpatients diagnosed with paranoid-type schizophrenia.ResultsLow nonverbal synchrony was indicative of symptoms, low social competence, impaired social functioning, and low self-evaluation of competence. These relationships remained largely significant when correcting for the amounts of patients‘ movement. When patients showed reduced imitation of their interactants’ movements, negative symptoms were likely to be prominent. Conversely, positive symptoms were more prominent in patients when their interaction partners’ imitation of their movements was reduced.ConclusionsNonverbal synchrony can be an objective and sensitive indicator of the severity of patients’ problems. Furthermore, quantitative analysis of nonverbal synchrony may provide novel insights into specific relationships between symptoms, cognition, and core communicative problems in schizophrenia.
This study explored the utility of the impact response surface (IRS) approach for investigating model ensemble crop yield responses under a large range of changes in climate. IRSs of spring and winter wheat Triticum aestivum yields were constructed from a 26-member ensemble of process-based crop simulation models for sites in Finland, Germany and Spain across a latitudinal transect. The sensitivity of modelled yield to systematic increments of changes in temperature (-2 to + 9 degrees C) and precipitation (-50 to + 50%) was tested by modifying values of baseline (1981 to 2010) daily weather, with CO2 concentration fixed at 360 ppm. The IRS approach offers an effective method of portraying model behaviour under changing climate as well as advantages for analysing, comparing and presenting results from multi-model ensemble simulations. Though individual model behaviour occasionally departed markedly from the average, ensemble median responses across sites and crop varieties indicated that yields decline with higher temperatures and decreased precipitation and increase with higher precipitation. Across the uncertainty ranges defined for the IRSs, yields were more sensitive to temperature than precipitation changes at the Finnish site while sensitivities were mixed at the German and Spanish sites. Precipitation effects diminished under higher temperature changes. While the bivariate and multi-model characteristics of the analysis impose some limits to interpretation, the IRS approach nonetheless provides additional insights into sensitivities to inter-model and inter-annual variability. Taken together, these sensitivities may help to pinpoint processes such as heat stress, vernalisation or drought effects requiring refinement in future model developmen
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