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Rudi F Vogel - One of the best experts on this subject based on the ideXlab platform.
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interspecies Assertiveness of lactobacillus curvatus and lactobacillus sakei in sausage fermentations
International Journal of Food Microbiology, 2020Co-Authors: Dorothee Jansen, Matthias A. Ehrmann, Lena Dworschak, Christina Ludwig, Rudi F VogelAbstract:Lactobacillus (L.) curvatus and L. sakei contain strains, which are assertive in sausage fermentation. Previous work has demonstrated differences in Assertiveness at strain level within one species, and revealed either exclusion of competitors by complementary partner strains or their inhibition by single strains. This work addresses interspecies differences in the Assertiveness of L. curvatus and L. sakei. Strain sets of L. curvatus and L. sakei were employed as starters in a fermented sausage model and their abundancy upon fermentation was determined by strain-specific MALDI-TOF MS identification. Generally, single or groups of L. sakei strains outcompeted L. curvatus strains. In multiple growth tests employing mMRS and mMSM it could be shown that assertive L. sakei strains can be predicted along their μ max in mMSM. Still, L. curvatus TMW 1.624 could suppress all L. curvatus and most L. sakei strains in competitive settings. This could be referred to its expression of several bacteriocins, which are active against all of the L. curvatus strains. Strain specific differences could be demonstrated in the susceptibility of L. sakei to bacteriocins, and in oxidative stress tolerance, which is higher in co-existing L. sakei strains than in the bacteriocin producer. This suggests that tolerance to bacteriocins and oxidative stress represent additional determinants for Assertiveness, above previously reported bacteriocin production versus metabolic complementarism of partner strains.
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comparative genomics of lactobacillus curvatus enables prediction of traits relating to adaptation and strategies of Assertiveness in sausage fermentation
International Journal of Food Microbiology, 2018Co-Authors: Lara Eisenbach, Dorothee Jansen, Matthias A. Ehrmann, Rudi F VogelAbstract:Lactobacillus (L.) curvatus reaches high numbers in a variety of habitats, which suggests a high (genomic) diversity within this species. Empirically selected strains are used as starter cultures in sausage fermentation. Determinants for the Assertiveness of a strain in this environment are assumed to be multifactorial. We used comparative genomics and in silico proteomics of 10 L. curvatus strains, which were representative of its genetic and physiological biodiversity, to possibly derive genetic determinants for strain or group specific Assertiveness in sausage fermentation. Their genome sizes ranged from 1.7 Mb up to 2.0 Mb. The estimated pan- and core genomes were 3.0 Mb and 1.4 Mb, respectively. The accessory genome, GC-content and coding density revealed a significant genomic diversity within this species. Plasmids were found, which were either closely related or unique in several strains. Putative Assertiveness determinants including CRISPR/Cas systems, prophages, bacteriocin production, or specific metabolic settings were detected. Such traits of the accessory genome could not be correlated with the source of isolation. Pathways, which previously have been predicted for a relation with adaptation to meat of L. sakei, are part of the core genome of L curvatus. Intraspecies differences in the accessory genome of L. curvatus comprise ribose metabolism, enzymes involved in nucleotide metabolism (nucleoside phosphorylases, phosphopentomutase, adenosine deaminase, ribose transporters), and tyrosine decarboxylases, ornithine decarboxylases. One group of the strains encoded a phosphotransferase system (PTS) as ribose transporter, whereas the second group encoded an ATP binding cassette (ABC) transporter. Analysis of the ribose uptake by HPLC analysis revealed different efficiencies of both transporter systems. Except for bacteriocin formation, no strain specific traits were identified predicting Assertiveness of single strains. This fits our previous observation that single strains of L. curvatus could not override others in a competitive setting. Rather, pairs or sets of strains, comprising metabolically synergistic or non-assertive partner strains were able to dominate the fermentation. Indeed, this work suggests that assertive partnerships can be predicted along their complementary accessory genomes.
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Monitoring of Assertive Lactobacillus Sakei and Lactobacillus Curvatus Strains Using an Industrial Ring Trial Experiment
Journal of applied microbiology, 2018Co-Authors: Dorothee Janßen, Matthias A. Ehrmann, Rudi F VogelAbstract:Aims In a previous study, we used a 5-day fermenting sausage model to characterize Assertiveness of Lactobacillus curvatus and Lactobacillus sakei starter strains towards employ autochthonous contaminants. In this work, we probed those findings and their transferability to real sausage fermentation including the drying process in an industrial ring trial experiment. Methods and results Raw fermented sausages ('salami') were produced with three L. curvatus and four L. sakei strains as starter cultures in cooperation with three manufacturers from Germany. We monitored pH, water activity and microbiota dynamics at strain level over a total fermentation and ripening time of 21 days by MALDI-TOF-MS identification of isolates. The principal behaviour of the strains in real sausage fermentations was the same as that one observed in the 5-day model system delineating single strain Assertiveness of a bacteriocin producer from co-dominance of strains. Conclusions The water activity decrease, which is concomitant with the sausage ripening process has only limited impact on the Assertiveness and survival of the starter strains. Significance and impact of the study Results of a 5-day model can provide insight in the Assertiveness of a specific starter strain in sausage fermentation.
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Assertiveness of lactobacillus sakei and lactobacillus curvatus in a fermented sausage model
International Journal of Food Microbiology, 2018Co-Authors: Dorothee Jansen, Matthias A. Ehrmann, Lara Eisenbach, Rudi F VogelAbstract:Fresh meat harbors autochthonous microbiota with unknown risk potential, which is introduced in raw fermented sausages. Their growth can be limited by the use of safe, competitive starter strains. In the lack of time and cost-effective methods to track those starters at strain level, their Assertiveness upon meat fermentation is widely unknown. Lactobacillus (L.) sakei and L. curvatus, which can be isolated from a variety of habitats, are frequently used as starter cultures. We monitored the Assertiveness of 9 L. sakei and 9 L. curvatus strains in a model fermentation using MALDI-TOF-MS. An "in-house" MALDI-TOF-MS database with sub-proteome spectra of L. sakei and L. curvatus strains, as well as members of the autochthonous, spontaneously growing meat microbiota was established, validated and recognition rates were determined for each L. curvatus and L. sakei strain used. Competition studies were performed with standardized sausage batter, which was inoculated with a total of 106 cells of sets of 4-5 strains each of L. sakei and L. curvatus and 106Staphylococcus carnosus ssp. carnosus cells. The pH and redox potential were monitored continuously. On days 0, 2 and 5 samples were taken to determine the CfU/g and a total of 96 isolates per sample were identified via MALDI-TOF-MS. MALDI-TOF-MS generally proved suitable for identification of isolates on strain level within the starter sets employed, but the recognition rate varied depending on the strain. Competition studies revealed dominance or co-dominance of strains within each set. However, their Assertiveness significantly depended on the composition of the strain sets. Still, co-dominance or cooperation appeared effective to outgrow other members of the autochthonous meat microbiota, rather than dominance of single strains. For the latter, the ability to produce bacteriocins suggested itself for a crucial role in the Assertiveness of starter strains.
Kristin L Hackl - One of the best experts on this subject based on the ideXlab platform.
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role play assessments of sexual Assertiveness skills relationships with hiv aids sexual risk behavior practices
Aids and Behavior, 1998Co-Authors: Anton M Somlai, Jeffrey A Kelly, Timothy L Mcauliffe, Jeffrey L Gudmundson, Debra A Murphy, Kathleen J Sikkema, Kristin L HacklAbstract:Conceptual formulations of HIV risk reduction and many HIV prevention interventions reported in the literature emphasize the role of sexual Assertiveness, negotiation, and communication skills as key elements for enacting behavior change. However, there have been few attempts to determine if objective ratings of individuals' sexual communication skill effectiveness are actually associated with their levels of HIV sexual risk behavior. In the current study, 114 severely mentally ill men and women role-played scenes in which confederates simulated attempts to coerce unprotected sex. Participants' role-played responses were transcribed verbatim and later rated for quality in several areas of Assertiveness skill effectiveness. In addition, participants provided detailed information concerning their sexual behavior practices in the past 30 days. Participants were categorized into highly, intermediately, or poorly skilled groups based on effectiveness in role play performance, and the groups were then compared on indices of HIV risk behavior. Individuals with high objectively rated sexual Assertiveness skill had the lowest number of unprotected sex acts, the smallest number of different sexual partners, the smallest number of casual sex partners, and the highest levels of condom-protected sex in the past 30 days. Individuals with poor sexual Assertiveness role-play skills had the highest levels of sexual risk behavior. These associations were especially pronounced among women. Findings of this research provide support for teaching individuals to develop and refine their sexual Assertiveness and communication skills in HIV prevention programs. Future research issues in this area are highlighted.
Audrey Brassard - One of the best experts on this subject based on the ideXlab platform.
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attachment sexual Assertiveness and sexual outcomes in women with provoked vestibulodynia and their partners a mediation model
Archives of Sexual Behavior, 2015Co-Authors: Bianca Leclerc, Sophie Bergeron, Audrey Brassard, Claude Belanger, Marc Steben, Bernard LambertAbstract:Provoked vestibulodynia (PVD) is a prevalent women’s sexual pain disorder, which is associated with sexual function difficulties. Attachment theory has been used to understand adult sexual outcomes, providing a useful framework for examining sexual adaptation in couples confronted with PVD. Research to date indicates that anxious and avoidant attachment dimensions correlate with worse sexual outcomes in community and clinical samples. The present study examined the association between attachment, pain, sexual function, and sexual satisfaction in a sample of 101 couples in which the women presented with PVD. The actor–partner interdependence model was used in order to investigate both actor and partner effects. This study also examined the role of sexual Assertiveness as a mediator of these associations via structural equation modeling. Women completed measures of pain intensity and both members of the couple completed measures of romantic attachment, sexual Assertiveness, sexual function, and satisfaction. Results indicated that attachment dimensions did not predict pain intensity. Both anxious and avoidant attachment were associated with lower sexual satisfaction. Only attachment avoidance predicted lower sexual function in women. Partner effects indicated that higher sexual Assertiveness in women predicted higher sexual satisfaction in men. Finally, women’s sexual Assertiveness was found to be a significant mediator of the relationship between their attachment dimensions, sexual function, and satisfaction. Findings highlight the importance of examining how anxious and avoidant attachment may lead to difficulties in sexual Assertiveness and to less satisfying sexual interactions in couples where women suffer from PVD.
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attachment insecurities and women s sexual function and satisfaction the mediating roles of sexual self esteem sexual anxiety and sexual Assertiveness
Journal of Sex Research, 2015Co-Authors: Audrey Brassard, Sophie Bergeron, Emmanuelle Dupuy, Phillip R ShaverAbstract:We examined the potential role of three mediators—sexual self-esteem, sexual anxiety, and sexual Assertiveness—of the association between romantic attachment insecurities (anxiety and avoidance) and two aspects of women's sexual functioning: sexual function and sexual satisfaction. A sample of 556 women aged 18 to 30 agreed to complete an online series of validated questionnaires assessing attachment insecurities and several aspects of sexual functioning. Lower sexual self-esteem and higher sexual anxiety mediated the associations between attachment anxiety and lower sexual function and satisfaction. Lower sexual self-esteem and higher sexual anxiety also partially mediated the links between attachment-related avoidance and the two sexual functioning variables. Sexual Assertiveness, however, did not mediate these associations. A significant interaction between attachment anxiety and avoidance was also found to predict sexual satisfaction, with women high in avoidance and low in anxiety being the least sat...
Jennifer A. Livingston - One of the best experts on this subject based on the ideXlab platform.
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prospective prediction of women s sexual victimization by intimate and nonintimate male perpetrators
Journal of Consulting and Clinical Psychology, 2007Co-Authors: Maria Testa, Carol Vanziletamsen, Jennifer A. LivingstonAbstract:Although behavioral risk factors such as substance use have been hypothesized to increase women’s vulnerability to sexual victimization, prospective studies provide mixed empirical support. In the current prospective study, the authors considered substance use, sexual activity, and sexual Assertiveness as predictors of sexual victimization from intimate partners and nonintimate perpetrators. Among a representative community sample of women ages 18–30 years (N = 927), 17.9% reported sexual victimization over 2 years, the majority by an intimate partner. Low sexual refusal Assertiveness, drug use, and prior intimate partner victimization predicted intimate partner sexual victimization. Heavy episodic drinking and number of sexual partners predicted victimization from nonintimates. The finding that there are different risk factors for sexual victimization from intimates versus nonintimates suggests the need for tailored prevention strategies.
Anton M Somlai - One of the best experts on this subject based on the ideXlab platform.
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role play assessments of sexual Assertiveness skills relationships with hiv aids sexual risk behavior practices
Aids and Behavior, 1998Co-Authors: Anton M Somlai, Jeffrey A Kelly, Timothy L Mcauliffe, Jeffrey L Gudmundson, Debra A Murphy, Kathleen J Sikkema, Kristin L HacklAbstract:Conceptual formulations of HIV risk reduction and many HIV prevention interventions reported in the literature emphasize the role of sexual Assertiveness, negotiation, and communication skills as key elements for enacting behavior change. However, there have been few attempts to determine if objective ratings of individuals' sexual communication skill effectiveness are actually associated with their levels of HIV sexual risk behavior. In the current study, 114 severely mentally ill men and women role-played scenes in which confederates simulated attempts to coerce unprotected sex. Participants' role-played responses were transcribed verbatim and later rated for quality in several areas of Assertiveness skill effectiveness. In addition, participants provided detailed information concerning their sexual behavior practices in the past 30 days. Participants were categorized into highly, intermediately, or poorly skilled groups based on effectiveness in role play performance, and the groups were then compared on indices of HIV risk behavior. Individuals with high objectively rated sexual Assertiveness skill had the lowest number of unprotected sex acts, the smallest number of different sexual partners, the smallest number of casual sex partners, and the highest levels of condom-protected sex in the past 30 days. Individuals with poor sexual Assertiveness role-play skills had the highest levels of sexual risk behavior. These associations were especially pronounced among women. Findings of this research provide support for teaching individuals to develop and refine their sexual Assertiveness and communication skills in HIV prevention programs. Future research issues in this area are highlighted.
