scholarly journals Exploring Secondary Metabolite Profiles of Stachybotrys spp. by LC-MS/MS

Toxins ◽  
2019 ◽  
Vol 11 (3) ◽  
pp. 133 ◽  
Author(s):  
Annika Jagels ◽  
Viktoria Lindemann ◽  
Sebastian Ulrich ◽  
Christoph Gottschalk ◽  
Benedikt Cramer ◽  
...  

The genus Stachybotrys produces a broad diversity of secondary metabolites, including macrocyclic trichothecenes, atranones, and phenylspirodrimanes. Although the class of the phenylspirodrimanes is the major one and consists of a multitude of metabolites bearing various structural modifications, few investigations have been carried out. Thus, the presented study deals with the quantitative determination of several secondary metabolites produced by distinct Stachybotrys species for comparison of their metabolite profiles. For that purpose, 15 of the primarily produced secondary metabolites were isolated from fungal cultures and structurally characterized in order to be used as analytical standards for the development of an LC-MS/MS multimethod. The developed method was applied to the analysis of micro-scale extracts from 5 different Stachybotrys strains, which were cultured on different media. In that process, spontaneous dialdehyde/lactone isomerization was observed for some of the isolated secondary metabolites, and novel stachybotrychromenes were quantitatively investigated for the first time. The metabolite profiles of Stachybotrys species are considerably influenced by time of growth and substrate availability, as well as the individual biosynthetic potential of the respective species. Regarding the reported adverse effects associated with Stachybotrys growth in building environments, combinatory effects of the investigated secondary metabolites should be addressed and the role of the phenylspirodrimanes re-evaluated in future research.

Agriculture ◽  
2020 ◽  
Vol 10 (3) ◽  
pp. 72 ◽  
Author(s):  
Maria Michela Salvatore ◽  
Carina Félix ◽  
Fernanda Lima ◽  
Vanessa Ferreira ◽  
Daniele Naviglio ◽  
...  

In the course of investigations on the role of secondary metabolites in plant-microbe interactions, the production of secondary metabolites by Macrophomina phaseolina isolates from Eucalyptus globulus, was studied. This fungus is responsible for several plant diseases which affect crop productivity and industry. Although secondary metabolites may play a role in disease development, there are very few reports on M. phaseolina metabolomics and, as far as we know, isolates from eucalypts have not been investigated for secondary metabolites production. In the present paper, metabolites typical of fungi, from the family Botryosphaeriaceae, were identified for the first time as products of M. phaseolina. Furthermore, the isolate under examination was grown in the presence and absence of host stem tissue, and metabolite profiles were compared. Five products are reported for the first time in this species and azelaic acid was exclusively produced in the presence of eucalypt stem. Finally, phytotoxicity and cytotoxicity tests of culture filtrates and crude organic extracts were also performed. Key Contribution: Lipophilic metabolites produced by M. phaseolina might play a role in the plant-fungus interactions responsible for serious diseases of E. globulus.


Author(s):  
Katherine H. Rogers

When forming impressions of an other’s personality, people often rely on information not directly related to the individual at hand. One source of information that can influence people’s impressions of others is the personality of the average person (i.e., normative profile). This relationship between the normative profile and an impression is called normative accuracy or normativity. In this chapter, you will learn about the average personality, why it is important, the relationship to social desirability and what it means to have a normative impression, as well as correlates and moderators of normativity. More broadly, you will learn about current research and views regarding the normative profile and normative impressions as well as concrete steps for incorporating this approach into your future research on interpersonal perception.


Author(s):  
Kalin Z. Salinas ◽  
Amanda Venta

The current study proposed to determine whether adolescent emotion regulation is predictive of the amount and type of crime committed by adolescent juvenile offenders. Despite evidence in the literature linking emotion regulation to behaviour problems and aggression across the lifespan, there is no prior longitudinal research examining the predictive role of emotion regulation on adolescent recidivism, nor data regarding how emotion regulation relates to the occurrence of specific types of crimes. Our primary hypothesis was that poor emotion regulation would positively and significantly predict re-offending among adolescents. We tested our hypothesis within a binary logistic framework utilizing the Pathways to Desistance longitudinal data. Exploratory bivariate analyses were conducted regarding emotion regulation and type of crime in the service of future hypothesis generation. Though the findings did not indicate a statistically significant relation between emotion regulation and reoffending, exploratory findings suggest that some types of crime may be more linked to emotion regulation than others. In sum, the present study aimed to examine a hypothesized relation between emotion regulation and juvenile delinquency by identifying how the individual factor of dysregulated emotion regulation may have played a role. This study’s findings did not provide evidence that emotion regulation was a significant predictor of recidivism over time but did suggest that emotion regulation is related to participation in certain types of crime one year later. Directions for future research that build upon the current study were described. Indeed, identifying emotion regulation as a predictor of adolescent crime has the potential to enhance current crime prevention efforts and clinical treatments for juvenile offenders; this is based on the large amount of treatment literature, which documents that emotion regulation is malleable through treatment and prevention programming.


2016 ◽  
Vol 62 (1) ◽  
pp. 65-82 ◽  
Author(s):  
J. Orlowsky

Abstract A large number of infrastructural concrete buildings are protected against aggressive environments by coating systems. The functionality of these coating systems is mainly affected by the composition and thickness of the individual polymeric layers. For the first time ever, a mobile nuclear magnetic resonance (NMR) sensor allows a non-destructive determination of these important parameters on the building site. However, before this technique can be used on steel-reinforced concrete elements, the potential effect of the reinforcement on the measurement, i.e. the NMR signal, needs to be studied. The results show a shift of the NMR profile as well as an increase of the signals amplitude in the case of the reinforced samples, while calculating the thickness of concrete coating leading to identical results.


Molecules ◽  
2019 ◽  
Vol 24 (3) ◽  
pp. 523 ◽  
Author(s):  
Xue-min Zhu ◽  
Yu Li ◽  
Fei Xu ◽  
Wei Gu ◽  
Guo-jun Yan ◽  
...  

The measurement of skin electrical resistance (SER) has drawn a great deal of attention for the rapid screening of transdermal penetration enhancers (PEs). However, the mechanisms underlying the SER measurement are still unclear. This study was to investigate the effects and mechanisms of seven oxygen-containing terpenes on the SER kinetics. Stratum corneum (SC) lipids were proved to play a key role in SER measurement. Then, the factors affecting the SER measurement were optimized. By the determination of SER kinetics, cyclic terpenes (1,8-cineole, terpinen-4-ol, menthol and α-terpineol) were demonstrated to possess higher enhancement ratio (ER) values compared with linear terpenes (linalool, geraniol and citral). For the first time, the linear correlation was found between ER of terpenes and the interaction energy of terpene–ceramide complexes revealed by molecular simulation. The attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR) analysis revealed that the effect of cyclic terpenes on SC lipid arrangement was obviously stronger than that of linear terpenes. In addition, by evaluating HaCaT skin cell viability, little difference was found between the toxicities of cyclic and linear terpenes. In conclusion, measurement of SER could be a feasible approach for the efficient evaluation of the PEs that mainly act on SC lipids.


2018 ◽  
Vol 31 (2) ◽  
pp. 334-351 ◽  
Author(s):  
Ronald Busse ◽  
Ufuk Doganer

Purpose Fuelled by the latest scandals at Siemens, VW or Walmart, there is a lively debate on the role of compliance and ethics programmes. Unlike large corporations, small and medium-sized enterprises (SMEs) arguably tend to underestimate their significance and lag behind. Hence, the purpose of this paper is to shed light on the process of introducing compliance codes and its effects on employee acceptance and performance. Design/methodology/approach In line with the qualitative methodology, the authors conducted 12 in-depth interviews with German SME employees which the authors evaluated with the qualitative content analysis. Findings As for the major contribution, results indicate the emergence of a lack of understanding, anger, anxiety and operational performance losses – both at the individual and the corporate level – especially when employees feel uninvolved in the initial introduction stadium. Originality/value Practicing managers may benefit from the recommendation to facilitate staff involvement at earlier stages. As for theory advancement, the authors draw on Kotter’s (2007) long surviving “Eight Steps Change Management Model” and find significant support for shifting the spotlight of attention towards the first four phases. The authors discuss the original value of the research, admit limitations and illuminate some promising future research trajectories.


2019 ◽  
Vol 39 (4) ◽  
pp. 503-524 ◽  
Author(s):  
Ofer Zwikael ◽  
Jack R. Meredith ◽  
John Smyrk

Purpose Recent research has proposed the position of a project owner as the individual accountable for realizing target benefits. However, there is a lack of understanding in the literature of this role – in particular, the specific responsibilities of the project owner that can enhance benefits realization and operations performance. The paper aims to discuss this issue. Design/methodology/approach The paper identifies these responsibilities in practice through two studies – a qualitative study, which includes interviews with senior executives who fund projects, and an in-depth longitudinal case study, which describes a company that continuously realizes the benefits from its projects. Findings The results suggest that a project owner should have 22 key responsibilities across four project phases and that an operations manager is often the most suitable candidate to fulfill this role in operations improvement projects. When performing these project responsibilities effectively, operations managers enhance benefits realization and operations improvement. Finally, the paper proposes five hypotheses for future research. Originality/value Based on agency theory, the paper increases our knowledge of the role of the project owner in practice. This new knowledge can enhance the realization of target benefits from projects and ensure a smooth transition from the project to the operations environment.


2019 ◽  
Vol 12 (1) ◽  
pp. 35-64
Author(s):  
Luz Marcela Hurtado ◽  
Ivan Ortega-Santos

Abstract Our goal is to explore the intersection of two bodies of literature, namely, the one on impersonal constructions with an emphasis on uno ‘one’, and the one on the effect of transitivity and the focus of attention on the distribution of overt vs. null pronouns, where it has been shown that overt pronominal subjects are disfavored in transitive contexts as opposed to intransitive contexts. Through a variationist analysis of the expression of uno in Barranquilla, Colombia, in the PRESSEA-BARRANQUILLA corpus, we extend this line of inquiry to this impersonal pronoun and study in detail for the first time the effect of the various components of transitivity on the distribution of overt pronouns. Specifically, various transitivity parameters put forward by Hopper and Thompson are shown to correctly predict the distribution of uno, namely, number of participants and kinesis whereas sentence polarity, aspect and individuation of the object yield mixed results meriting future research.


2017 ◽  
Vol 19 (2) ◽  
pp. 155-160 ◽  
Author(s):  
Anika Sud ◽  
Piotr Szawarski

The tragic case of Mayra Cabrera who died as a result of wrong route drug administration is notable as it was the first time a verdict of unlawful killing was recorded against an NHS Trust. Error within medicine is a significant cause of patient morbidity and mortality. We explore the costs of error, the dynamics of error causation, the role of both the individual and institution in accountability for error, as well as transferrable lessons from other industries to reduce error.


2012 ◽  
Vol 5 (4) ◽  
pp. 169-172 ◽  
Author(s):  
Vasil N. Atanasov ◽  
Silviya Stoykova ◽  
Yana Goranova ◽  
Mariana Mitewa ◽  
Svetla Petrova

ABSTRACT Vipoxin is a heterodimeric neurotoxin isolated from the venom of the Bulgarian long-nosed viper Vipera ammodytes meridionalis. Vipoxin represents a noncovalent association of two subunits - a basic and toxic phospholipase A2 enzyme, and an acidic nonenzymatic component (vipoxin’s acidic component). It was postulated that the phospholipase A2 subunit was more toxic than the whole vipoxin complex and the function of the acidic component was to reduce the enzymatic and toxic activities of the basic phospholipase A2. In the present study, we report new data on the acute toxicity (LD50) of vipoxin and its individual separated components. Vipoxin LD50 (mice, i.p. and i.v.) values were found to be 0.7-1.2 mg/kg b.w. (i.p.) and 0.9-1.3 mg/kg b.w. (i.v.). The established LD50 values for the separated pure phospholipase A2 subunit are higher - 10.0-13.0 mg/kg b.w (i.p.) and 2.2-3.0 mg/kg b.w. (i.v.), i.e. the individual phospholipase A2 subunit displays less toxic activity than vipoxin, contrary to the data published in the literature. The reconstituted vipoxin complex (obtained after preliminary incubation of pure separated phospholipase A2 and acidic component showed enzyme activity and toxicity comparable to that of the native vipoxin complex. Addition of acidic component to the phospholipase A2 subunit showed a positive effect on the enzymatic activity, reaching maximal enzyme reaction rate of acidic component to phospholipase A2 molar ratio of 0.8:1 on using 4-nitro-3-octanoyloxy-benzoic acid as substrate. For the first time we showed that the acidic subunit was absolutely required for the toxic activity of vipoxin. Based on the obtained results, we assume that the function of the acidic component is to stabilize the neurotoxin’s quaternary structure, required for its toxic and enzymatic activities, similarly to the role of the acidic component of crotoxin.


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