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Clostridium botulinum is a notorious pathogen that raises health and food safety concerns by producing the potent botulinum neurotoxin and causing botulism, a potentially fatal neuroparalytic disease in humans and animals. Efficient methods for the identification and isolation of C. botulinum are warranted for laboratory diagnostics of botulism and for food safety risk assessment. The cell wall binding domains (CBD) of phage lysins are recognized by their high specificity and affinity to distinct types of bacteria, which makes them promising for the development of diagnostic tools. We previously identified CBO1751, which is the first antibotulinal phage lysin showing a lytic activity against C. botulinum Group I. In this work, we assessed the host specificity of the CBD of CBO1751 and tested its feasibility as a probe for the specific isolation of C. botulinum Group I strains. We show that the CBO1751 CBD specifically binds to C. botulinum Group I sensu lato (including C. sporogenes) strains. We also demonstrate that some C. botulinum Group I strains possess an S-layer, the disruption of which by an acid glycine treatment is required for efficient binding of the CBO1751 CBD to the cells of these strains. We further developed CBO1751 CBD-based methods using flow cytometry and magnetic separation to specifically isolate viable cells of C. botulinum Group I. These methods present potential for applications in diagnostics and risk assessment in order to control the botulism hazard.  相似文献   
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Microglia are involved in the post-stroke immunomodulation of brain plasticity, repair, and reorganization. Here, we evaluated whether adipose-tissue-derived mesenchymal stem cells (ADMSCs) and/or rehabilitation improve behavioral recovery by modulating long-term perilesional inflammation and creating a recovery-permissive environment in a rat model of ischemic stroke. Methods: A two-way mixed lymphocyte reaction was used to assess the immunomodulatory capacity of ADMSCs in vitro. Two or 7 days after permanent middle cerebral artery occlusion (pMCAO), rats were intravenously administered ADMSCs or vehicle and housed in a standard or enriched environment (EE). Behavioral performance was assessed with a cylinder test, then we performed stereological and ImageJ/Fiji quantifications of ionized calcium-binding adaptor molecule 1 (Iba1) cells and blood–brain barrier (BBB) leakage. Results: Human ADMSCs were immunosuppressive in vitro. The cylinder test showed partial spontaneous behavioral recovery of pMCAO rats, which was further improved by combined ADMSCs and housing in EE on days 21 and 42 (p < 0.05). We detected an ischemia-induced increase in numbers, staining intensity, and branch length of Iba1+ microglia/macrophages as well as BBB leakage in the perilesional cortex. However, these were not different among pMCAO groups. Conclusion: Combined cell therapy and rehabilitation additively improved behavioral outcome despite long-term perilesional microglia presence in stroke rats.  相似文献   
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Clostridium botulinum is a notorious foodborne pathogen. Its ability to adapt to and grow at low temperatures is of interest for food safety. Two-component systems (TCSs) have been reported to be involved in cold-shock and growth at low temperatures. Here we show the importance of TCS CBO2306/CBO2307 in the cold-shock response of C. botulinum ATCC 3502. The relative expression levels of the cbo2306 and cbo2307 were up to 4.4-fold induced in the cold-shocked cultures but negatively regulated in the late-log and stationary growth phase in relation to early logarithmic growth phase in non-shocked cultures. Importance of the CBO2306/CBO2307 in the cold stress was further demonstrated by impaired growth of insertional cbo2306 or cbo2307 knockout mutants in relation to the wild-type strain ATCC 3502. The results suggest that the TCS CBO2306/CBO2307 is important for cold-shock response and adaptation of C. botulinum ATCC 3502 to low temperature.  相似文献   
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The authors examined emotional valence- and arousal-related phasic psychophysiological responses to different violent events in the first-person shooter video game "James Bond 007: NightFire" among 36 young adults. Event-related changes in zygomaticus major, corrugator supercilii, and orbicularis oculi electromyographic (EMG) activity and skin conductance level (SCL) were recorded, and the participants rated their emotions and the trait psychoticism based on the Psychoticism dimension of the Eysenck Personality Questionnaire--Revised, Short Form. Wounding and killing the opponent elicited an increase in SCL and a decrease in zygomatic and orbicularis oculi EMG activity. The decrease in zygomatic and orbicularis oculi activity was less pronounced among high Psychoticism scorers compared with low Psychoticism scorers. The wounding and death of the player's own character (James Bond) elicited an increase in SCL and zygomatic and orbicularis oculi EMG activity and a decrease in corrugator activity. Instead of joy resulting from victory and success, wounding and killing the opponent may elicit high-arousal negative affect (anxiety), with high Psychoticism scorers experiencing less anxiety than low Psychoticism scorers. Although counterintuitive, the wounding and death of the player's own character may increase some aspect of positive emotion. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Companies struggle with the sub-optimization and changes among their projects, even if various normative instructions and good practices have been introduced for project portfolio management. At the center of this paper is the need to understand project portfolio management in practice and in context. The purpose is to report a review on recent empirical research literature regarding project portfolio management, to draw attention to the limitations with viewing portfolio management as a rational decision process, and to develop new avenues for research regarding project portfolio management in practice and in context. As a result, this paper shows that, to respond to uncertainties and complexities in business environments, project portfolio management can be viewed as negotiation and bargaining and as structural reconfiguration, besides rational decision processes. These alternative perspectives offer new insight into the dilemmas identified in day-to-day project portfolio management and open up avenues for resolving them, thereby promoting success in project portfolio management.  相似文献   
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Carbohydrate-deficient transferrin (CDT) has previously been reported to be an excellent marker of male alcoholics. Less is known of its efficiency among women and especially of early-phase alcohol abuse in nonselected populations. The present population-based study examined the diagnostic value of CDT among consecutive women, including 13 teetotallers, 135 social drinkers (mean alcohol consumption 45 +/- 34 g/week), and 57 nonalcoholic heavy drinkers (197 +/- 97 g/week). Sixty-two women with a well-documented history of chronic alcoholism (942 +/- 191 g/week) were also studied, as well as 36 pregnant women used as a reference group. Two weeks of abstinence among 11 alcoholics was followed. The CDT (containing part of isotransferrin with pI = 5.7, 5.8, and 5.9) was separated by anion exchange chromatography and assayed by radioimmunoassay. In the whole material, CDT correlated significantly with alcohol consumption (r = 0.43, p < 0.001) but not with conventional markers (gamma-glutamyltransferase, AST, ALT, and mean corpuscular volume). The CDT values of alcoholics (34 +/- 20 units/liter) were significantly (p < 0.001) higher than those of teetotallers (19 +/- 6 units/liter), social drinkers (20 +/- 6 units/liter), or pregnant women (16 +/- 3 units/liter). Heavy drinkers also had higher values (25 +/- 13 units/liter), but the difference did not reach statistic significance. The specificity of CDT was on the level of conventional markers when the cut-off value was increased from 26 to 29 units/liter. At a specificity of 95%, CDT found 19% of the heavy drinkers and 52% of the alcoholics; the best traditional marker, AST, with a specificity of 97%, found 7% and 56%, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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